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Sample records for generation air-conditioning equipment

  1. Study of thermodynamic properties of HFC refrigerant mixtures for Loretz-cycled niew generation air-conditioning equipment; Lorentz cycle ka shinsedai kucho kikiyo HFC kei kongo reibai no netsu rikigaku seishitsu ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, K; Sato, H [Keio University, Tokyo (Japan). Faculty of Science and Technology

    1997-02-01

    This paper describes thermodynamic properties of HFC refrigerant mixtures for Lorentz-cycled new generation air-conditioning equipment. Equipment has been completed for simultaneous measurement of density and vapor-liquid equilibrium property, accurate measurement of latent heat of vaporization, and accurate measurement of specific heat at constant pressure in liquid phase. Final adjustment and preliminary measurements are currently conducted. Through analytical investigation using actually measured data of thermodynamic properties of HFC refrigerant mixtures, five state equations were obtained, i.e., modified Peng-Robinson state equation which can reproduce the vapor-liquid equilibrium property of refrigerant mixtures, modified Patel-Teja state equation, Helmholtz function type state equation which is applicable in the whole fluid region of refrigerant mixtures, and so on. An evaluation test equipment has been fabricated as a trial for Lorentz-cycled air-conditioning equipments using HFC refrigerant mixtures, and demonstration test is conducted to confirm the validity. 9 refs., 5 figs.

  2. FY1995 study of thermodynamic properties of HFC refrigerant mixtures for Lorentz-cycled new generation air-conditioning equipments; 1995 nendo Lorentz cycle ka shinsedai kucho kikiyo HFC kei kongo reibai no netsurikigaku seishitsu ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    A hydrochlorofluorocarbon (HCFC) refrigerant, R-22, is currently being used almost exclusively as a refrigerant for conventional air-conditioning equipments. Since HCFCs are expected to be banned shortly, it is considered a crucial issue to support R and D of the air-conditioning system Lorentz-cycled with hydrofluorocarbon (HFC) refrigerants mixtures. In the present research project, therefore, it is aimed to reveal some of the essential thermodynamic properties of HFC refrigerant mixtures systematically. On the basis of a series of achievements for the last several years by the present research coordinator and his group regarding thermodynamic properties of single-component and blended HFC refrigerants, we have conducted following three major research programs rather systematically on which no challenges have ever been reported worldwide. Throughout a series of experimental as well as analytical researches performed so as to meet the objectives mentioned above, some novel knowledge and valuable outcomes could be obtained in the present study. (1) Precise measurements of vapor-liquid equilibrium properties with simultaneous determination of densities, latent heats of vaporization, and isobaric specific heat capacities in liquid phase. (2) Analytical studies to establish thermodynamic property modeling. (3) Feasibility study of evaluating the Lorentz-cycled performance. (NEDO)

  3. Novel compact sorption generators for car air conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Tamainot-Telto, Z.; Metcalf, S.J.; Critoph, R.E. [School of Engineering, University of Warwick, Gibet Hill Road, Coventry CV4 7AL (United Kingdom)

    2009-06-15

    A prototype compact generator using the activated carbon-ammonia pair based on the plate heat exchanger concept has been designed and built at Warwick University. The novel generator has low thermal mass and good heat transfer. The heat exchanger uses nickel-brazed shims and spacers to create adsorbent layers only 4 mm thick between pairs of liquid flow channels of very low thermal mass. The prototype sorption generator manufactured was evaluated under EU car air conditioning test conditions. The prototype sorption generator is described and its experimental performance reported. While driven with waste heat from the engine coolant water (at 90 C), a pair of the current prototype generators (loaded with about 1 kg of activated carbon) operating out of phase has produced an average cooling power 1.6 kW with about 2 kW peaks. The typical average COP obtained is 0.22. (author) [French] Un prototype du generateur compact, base sur le concept des echangeurs de chaleur a plaques et utilisant la paire charbon actif-ammoniac, a ete concu et construit a l'Universite de Warwick. Le nouveau generateur a une faible inertie thermique et un excellent transfert de chaleur. L' echangeur utilise des plaques ayant des micro-canaux et des intercalaires brases au Nickel pour creer des couches d'adsorbant de 4 mm d'epaisseur entre les paires de plaques a l'interieur desquelles circule le fluide liquide. Le prototype du generateur a sorption ainsi fabrique a ete teste suivant des conditions prescrites par la Norme Europeenne de la Climatisation Automobile. Le prototype du generateur a sorption est decrit et ses performances experimentales presentees. Une paire dudit prototype (contenant chacun 1 kg the charbon actif), operant avec dephasage et ulisant des pertes thermiques en provenance de l'eau de refroidissement de moteur (a 90 C), a produit une puissance frigorifique moyenne de 1.6 kW avec une valeur maximum de 2 kW. La valeur typique du COP moyen est de

  4. An Analysis of Price Determination and Markups in the Air-Conditioning and Heating Equipment Industry

    Energy Technology Data Exchange (ETDEWEB)

    Dale, Larry; Millstein, Dev; Coughlin, Katie; Van Buskirk, Robert; Rosenquist, Gregory; Lekov, Alex; Bhuyan, Sanjib

    2004-01-30

    In this report we calculate the change in final consumer prices due to minimum efficiency standards, focusing on a standard economic model of the air-conditioning and heating equipment (ACHE) wholesale industry. The model examines the relationship between the marginal cost to distribute and sell equipment and the final consumer price in this industry. The model predicts that the impact of a standard on the final consumer price is conditioned by its impact on marginal distribution costs. For example, if a standard raises the marginal cost to distribute and sell equipment a small amount, the model predicts that the standard will raise the final consumer price a small amount as well. Statistical analysis suggest that standards do not increase the amount of labor needed to distribute equipment the same employees needed to sell lower efficiency equipment can sell high efficiency equipment. Labor is a large component of the total marginal cost to distribute and sell air-conditioning and heating equipment. We infer from this that standards have a relatively small impact on ACHE marginal distribution and sale costs. Thus, our model predicts that a standard will have a relatively small impact on final ACHE consumer prices. Our statistical analysis of U.S. Census Bureau wholesale revenue tends to confirm this model prediction. Generalizing, we find that the ratio of manufacturer price to final consumer price prior to a standard tends to exceed the ratio of the change in manufacturer price to the change in final consumer price resulting from a standard. The appendix expands our analysis through a typical distribution chain for commercial and residential air-conditioning and heating equipment.

  5. Proposal for energy saving in air conditioning equipment; Propuesta para ahorro energetico en acondicionadores de aire

    Energy Technology Data Exchange (ETDEWEB)

    Solis Recendez, Daniel H [Division de Ingenieria Electrica, Universidad Nacional Autonoma de Mexico (Mexico)

    2008-10-15

    In the last decades, the air conditioning systems have become a crucial part in the search from comfort in extreme climates. Nevertheless, they have also become one of the greatest energy consumers. In this article it is proposed that the final conditions that the air conditioning equipment looks for not to be fixed, but variable in respect to a certain comfort zone. This zone is a variation of the used one in the bio-climatic chart of Olgyay that considers the rapidity whereupon the reached conditions tend to leave the comfort zone. It is analyzed how to choose the point on the zone that costs less energy in arriving to it. [Spanish] En las ultimas decadas, los sistemas de aire acondicionado se han vuelto una parte crucial en la busqueda de confort en climas extremosos. Sin embargo, tambien se han vuelto de los mayores consumidores de energia. En este articulo se propone que las condiciones finales que busquen lograr los acondicionadores no sean fijas, si no variables respecto a una determinada zona de confort. Dicha zona es una variacion de la utilizada en la carta bioclimatica de Olgyay, que considera la rapidez con que las condiciones alcanzadas tienden a abandonar la zona de confort. Se discute como elegir el punto sobre la zona que cueste menos energia en llegara el.

  6. Influence of different outdoor design conditions on design cooling load and design capacities of air conditioning equipments

    International Nuclear Information System (INIS)

    Aktacir, Mehmet Azmi; Bueyuekalaca, Orhan; Bulut, Huesamettin; Yilmaz, Tuncay

    2008-01-01

    Outdoor design conditions are important parameters for energy efficiency of buildings. The result of incorrect selection of outdoor design conditions can be dramatic in view of comfort and energy consumption. In this study, the influence of different outdoor design conditions on air conditioning systems is investigated. For this purpose, cooling loads and capacities of air conditioning equipments for a sample building located in Adana, Turkey are calculated using different outdoor design conditions recommended by ASHRAE, the current design data used in Turkey and the daily maximum dry and wet bulb temperatures of July 21st, which is generally accepted as the design day. The cooling coil capacities obtained from the different outdoor design conditions considered in this study are compared with each other. The cost analysis of air conditioning systems is also performed. It is seen that the selection of outdoor design conditions is a very critical step in calculation of the building cooling loads and design capacities of air conditioning equipments

  7. Development of a method for calculating steady-state equipment sensible heat ratio of direct expansion air conditioning units

    International Nuclear Information System (INIS)

    Xia Liang; Chan, M.Y.; Deng Shiming

    2008-01-01

    A complete set of calculation method for steady-state equipment sensible heat ratio (SHR) for a direct expansion (DX) cooling coil has been developed and reported. The method was based on the fundamentals of energy conservation and heat and mass transfer taking place in the DX cooling coil, and was experimentally validated using an experimental DX A/C rig. With the method developed, the effect of refrigerant evaporating temperature at fixed inlet air conditions on equipment SHR has been theoretically analyzed. The validated method can be useful in further studying the inherent operating characteristics of a DX air conditioning (A/C) unit and in developing suitable control strategies for achieving higher energy efficiency and better indoor thermal environment

  8. Performance Analysis of Window Type Air Conditioning with Addition of Heat Exchanger Equipment

    Directory of Open Access Journals (Sweden)

    I Ketut Gede Wirawan

    2012-11-01

    Full Text Available One manner to be used to increase refregration effect is by flowing hot refrigerant out from condensor, it is then touched with the refrigerant out from evaporator on a heat exchanger of counterflow type. Experiment was done by taking samples of pressure at suction (p1 and discharge (p2 of compressor and box temperature (Tr1, Tr2, Tr3, Tr4. By knowing of pressure at suction (p1, the enthalpy into compressor is known. By assuming the process is isentropic (compressor, isobar (condenser and evaporator, and isenthalpy (expansion valve, the enthalpy into condensor, expansion valve and evaporator were known. In 60 minutes, compression work of air conditioning with heat exchanger is 31,588 kJ/kg, and without heat exchanger is 33,796 kJ/kg. Effect refrigeration average with modification is 155,55 kJ/kg and without modification was 153,40 kJ/kg so that coefficient of performance with modification more than without modification. Air conditioning with modification had initial refrigration rate was 67,193 J/s and 0,043 J/s at the end minute, meanwhile, refrigeration without modification had cooling rate at start 66,538 J/s and 0,935 J/s at the end.

  9. Analyses of an air conditioning system with entropy generation minimization and entransy theory

    International Nuclear Information System (INIS)

    Wu Yan-Qiu; Cai Li; Wu Hong-Juan

    2016-01-01

    In this paper, based on the generalized heat transfer law, an air conditioning system is analyzed with the entropy generation minimization and the entransy theory. Taking the coefficient of performance (denoted as COP ) and heat flow rate Q out which is released into the room as the optimization objectives, we discuss the applicabilities of the entropy generation minimization and entransy theory to the optimizations. Five numerical cases are presented. Combining the numerical results and theoretical analyses, we can conclude that the optimization applicabilities of the two theories are conditional. If Q out is the optimization objective, larger entransy increase rate always leads to larger Q out , while smaller entropy generation rate does not. If we take COP as the optimization objective, neither the entropy generation minimization nor the concept of entransy increase is always applicable. Furthermore, we find that the concept of entransy dissipation is not applicable for the discussed cases. (paper)

  10. Air conditioning and power generation for residential applications using liquid nitrogen

    International Nuclear Information System (INIS)

    Ahmad, Abdalqader; Al-Dadah, Raya; Mahmoud, Saad

    2016-01-01

    Highlights: • Using liquid nitrogen to provide power and air conditioning for domestic applications. • The proposed system leads to save energy and reduce the peak electricity demands. • Compared with conventional AC saving up to 36% was achieved at the current LN2 price. • The widespread of this technology leads to lower LN2 price and saving up to 81%. • The last configuration was the efficient system with overall thermal efficiency 74%. - Abstract: Current air conditioning (AC) systems consume a significant amount of energy, particularly during peak times where most electricity suppliers face difficulties to meet the users’ demands, and the global demands for AC systems have increased rapidly over the last few decades leading to significant power consumption and carbon dioxide emissions. This paper presents a new technique that uses liquid nitrogen (LN2) produced from renewable energy sources, or surplus electricity at off peak times, to provide cooling and power for domestic houses. Thermodynamic analyses of various cryogenic cycles have been carried out to achieve the most effective configuration that produces the maximum power output with minimum LN2 flow rate, to meet the required cooling of a 170 m"2 dwelling in Libya. A comparison with a conventional AC system was also made. Results showed that at the current LN2 prices, using LN2 to provide cooling and power demands of residential buildings is feasible and saves up to 36% compared to conventional air conditioning systems with an overall thermal efficiency of 74%. However, as the LN2 price decreases to around 1.3 pence per kg, the proposed technology will have significant advantages compared to conventional AC systems with savings of up to 81%.

  11. Next Generation Refrigeration Lubricants for Low Global Warming Potential/Low Ozone Depleting Refrigeration and Air Conditioning Systems

    Energy Technology Data Exchange (ETDEWEB)

    Hessell, Edward

    2013-12-31

    The goal of this project is to develop and test new synthetic lubricants that possess high compatibility with new low ozone depleting (LOD) and low global warming potential (LGWP) refrigerants and offer improved lubricity and wear protection over current lubricant technologies. The improved compatibility of the lubricants with the refrigerants, along with improved lubricating properties, will resulted in lower energy consumption and longer service life of the refrigeration systems used in residential, commercial and industrial heating, ventilating and air-conditioning (HVAC) and refrigeration equipment.

  12. International Energy Agency Building Energy Simulation Test and Diagnostic Method for Heating, Ventilating, and Air-Conditioning Equipment Models (HVAC BESTEST); Volume 1: Cases E100-E200

    Energy Technology Data Exchange (ETDEWEB)

    Neymark, J.; Judkoff, R.

    2002-01-01

    This report describes the Building Energy Simulation Test for Heating, Ventilating, and Air-Conditioning Equipment Models (HVAC BESTEST) project conducted by the Tool Evaluation and Improvement International Energy Agency (IEA) Experts Group. The group was composed of experts from the Solar Heating and Cooling (SHC) Programme, Task 22, Subtask A. The current test cases, E100-E200, represent the beginning of work on mechanical equipment test cases; additional cases that would expand the current test suite have been proposed for future development.

  13. Optimal replacement of residential air conditioning equipment to minimize energy, greenhouse gas emissions, and consumer cost in the US

    International Nuclear Information System (INIS)

    De Kleine, Robert D.; Keoleian, Gregory A.; Kelly, Jarod C.

    2011-01-01

    A life cycle optimization of the replacement of residential central air conditioners (CACs) was conducted in order to identify replacement schedules that minimized three separate objectives: life cycle energy consumption, greenhouse gas (GHG) emissions, and consumer cost. The analysis was conducted for the time period of 1985-2025 for Ann Arbor, MI and San Antonio, TX. Using annual sales-weighted efficiencies of residential CAC equipment, the tradeoff between potential operational savings and the burdens of producing new, more efficient equipment was evaluated. The optimal replacement schedule for each objective was identified for each location and service scenario. In general, minimizing energy consumption required frequent replacement (4-12 replacements), minimizing GHG required fewer replacements (2-5 replacements), and minimizing cost required the fewest replacements (1-3 replacements) over the time horizon. Scenario analysis of different federal efficiency standards, regional standards, and Energy Star purchases were conducted to quantify each policy's impact. For example, a 16 SEER regional standard in Texas was shown to either reduce primary energy consumption 13%, GHGs emissions by 11%, or cost by 6-7% when performing optimal replacement of CACs from 2005 or before. The results also indicate that proper servicing should be a higher priority than optimal replacement to minimize environmental burdens. - Highlights: → Optimal replacement schedules for residential central air conditioners were found. → Minimizing energy required more frequent replacement than minimizing consumer cost. → Significant variation in optimal replacement was observed for Michigan and Texas. → Rebates for altering replacement patterns are not cost effective for GHG abatement. → Maintenance levels were significant in determining the energy and GHG impacts.

  14. Environmental impact of the programs of substitution of room type air conditioning equipment; Impacto ambiental de los programas de sustitucion de equipos de aire tipo cuarto

    Energy Technology Data Exchange (ETDEWEB)

    Alarcon Aleman, Jose Mauricio [OLADE, Quito (Ecuador)

    2002-09-01

    The present article approaches in a general way the relation that exists between the environment and the saving of electrical energy, especially in the Programs of Demand Side Management (DSM). In particular form the potential environmental impacts are described, derived of the use and the discard of the room type air conditioning equipment, goes deep into the characteristics of their cooling fluids, as well as in the relation that these keep with the protocols of Montreal and Kyoto. Finally, this article comments the incidence which have, the manufacturers as the institutions that implement DSM programs, on the environmental part of the programs of substitution of room type air conditioning equipment. In addition it is briefly described, the pilot program developed by Fideicomiso para el Ahorro de Energia Electrica (FIDE) as a successful case. [Spanish] En forma general, el presente articulo aborda la relacion que existe entre el medio ambiente y el ahorro de energia electrica, especialmente en los Programas de Administracion por el Lado de la Demanda (ALD). En forma particular se describen los impactos ambientales potenciales, derivados del uso y desecho de los equipos de aire acondicionado tipo cuarto, se ahonda en las caracteristicas de sus refrigerantes, asi como en la relacion que estos guardan con los protocolos de Montreal y Kioto. Finalmente, se comenta la incidencia que tienen, tanto los fabricantes como las instituciones que implementan programas de ALD, sobre la parte ambiental de los programas de sustitucion de equipos de aire acondicionado tipo cuarto. Ademas se describe brevemente, el programa piloto desarrollado por el Fideicomiso para el Ahorro de Energia Electrica (FIDE) como un caso exitoso.

  15. SESSA: Expert system for the selection of air conditioning equipment; SESEAA: Sistema experto para la seleccion de equipos de aire acondicionado

    Energy Technology Data Exchange (ETDEWEB)

    Kemper Valverde, Nicolas; Cardenas Perez, Edgar [Laboratorio de Sistemas Inteligentes, Centro de Instrumentos de la Universidad Nacional Autonoma de Mexico (UNAM), Mexico, D. F. (Mexico)

    1998-12-31

    The problem of selecting air conditioning and refrigeration equipment is quite wide and complex, since it encompasses from the application of the basic principles of physics and of thermodynamics up to the classic engineering design problems; these in turn can be numberless since they vary from place to place depending on multiple factors such as the region geographic and economic conditions. On the other hand, account most be taken of several elements such as windows, walls, and its specific geographical orientation, roofs, floors, partitions, equipment, lighting, etc., all this exerts influence in the complexity that represents the selection process. This paper describes a useful informatics tool to make it easy the selection process in air conditioning installations, taking into account multiple saving and efficient use of energy criteria, reflected in the operation process of these installations. [Espanol] El problema de seleccion de sistemas de aire acondicionado y de refrigeracion es bastante amplio y complejo, ya que abarca desde la aplicacion de los principios basicos de la fisica y la termodinamica hasta los problemas clasicos de diseno de ingenieria; estos a la vez pueden ser innumerables ya que varian de un lugar a otro y de un proyecto a otro, dependiendo de multiples factores tales como las condiciones geograficas y economicas de la region. Por otra parte se deben tomar en cuenta diversos elementos como son: ventanas, muros y sus orientaciones especificas, techos, pisos, particiones, equipos, iluminacion, etc., todo esto influye en la complejidad que representa el proceso de seleccion. En el presente trabajo se describe una herramienta informatica para facilitar el proceso de seleccion de instalaciones de aire acondicionado, tomando en cuenta multiples criterios de ahorro y uso eficiente de energia que se reflejan durante el proceso de operacion de estas instalaciones.

  16. SESSA: Expert system for the selection of air conditioning equipment; SESEAA: Sistema experto para la seleccion de equipos de aire acondicionado

    Energy Technology Data Exchange (ETDEWEB)

    Kemper Valverde, Nicolas; Cardenas Perez, Edgar [Laboratorio de Sistemas Inteligentes, Centro de Instrumentos de la Universidad Nacional Autonoma de Mexico (UNAM), Mexico, D. F. (Mexico)

    1999-12-31

    The problem of selecting air conditioning and refrigeration equipment is quite wide and complex, since it encompasses from the application of the basic principles of physics and of thermodynamics up to the classic engineering design problems; these in turn can be numberless since they vary from place to place depending on multiple factors such as the region geographic and economic conditions. On the other hand, account most be taken of several elements such as windows, walls, and its specific geographical orientation, roofs, floors, partitions, equipment, lighting, etc., all this exerts influence in the complexity that represents the selection process. This paper describes a useful informatics tool to make it easy the selection process in air conditioning installations, taking into account multiple saving and efficient use of energy criteria, reflected in the operation process of these installations. [Espanol] El problema de seleccion de sistemas de aire acondicionado y de refrigeracion es bastante amplio y complejo, ya que abarca desde la aplicacion de los principios basicos de la fisica y la termodinamica hasta los problemas clasicos de diseno de ingenieria; estos a la vez pueden ser innumerables ya que varian de un lugar a otro y de un proyecto a otro, dependiendo de multiples factores tales como las condiciones geograficas y economicas de la region. Por otra parte se deben tomar en cuenta diversos elementos como son: ventanas, muros y sus orientaciones especificas, techos, pisos, particiones, equipos, iluminacion, etc., todo esto influye en la complejidad que representa el proceso de seleccion. En el presente trabajo se describe una herramienta informatica para facilitar el proceso de seleccion de instalaciones de aire acondicionado, tomando en cuenta multiples criterios de ahorro y uso eficiente de energia que se reflejan durante el proceso de operacion de estas instalaciones.

  17. Air conditioning system with supplemental ice storing and cooling capacity

    Science.gov (United States)

    Weng, Kuo-Lianq; Weng, Kuo-Liang

    1998-01-01

    The present air conditioning system with ice storing and cooling capacity can generate and store ice in its pipe assembly or in an ice storage tank particularly equipped for the system, depending on the type of the air conditioning system. The system is characterized in particular in that ice can be produced and stored in the air conditioning system whereby the time of supplying cooled air can be effectively extended with the merit that the operation cycle of the on and off of the compressor can be prolonged, extending the operation lifespan of the compressor in one aspect. In another aspect, ice production and storage in great amount can be performed in an off-peak period of the electrical power consumption and the stored ice can be utilized in the peak period of the power consumption so as to provide supplemental cooling capacity for the compressor of the air conditioning system whereby the shift of peak and off-peak power consumption can be effected with ease. The present air conditioning system can lower the installation expense for an ice-storing air conditioning system and can also be applied to an old conventional air conditioning system.

  18. Simulation of an air conditioning absorption refrigeration system in a co-generation process combining a proton exchange membrane fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Pilatowsky, I.; Gamboa, S.A.; Rivera, W. [Centro de Investigacion en Energia - UNAM, Temixco, Morelos (Mexico); Romero, R.J. [Centro de Investigacion en Ingenieria y Ciencias Aplicadas - UAEM, Cuernavaca, Morelos (Mexico); Isaza, C.A. [Universidad Pontificia Bolivariana, Medellin (Colombia). Instituto de Energia y Termodinamica; Sebastian, P.J. [Centro de Investigacion en Energia - UNAM, Temixco, Morelos (Mexico); Cuerpo Academico de Energia y Sustentabilidad-UP Chiapas, Tuxtla Gutierrez, Chiapas (Mexico); Moreira, J. [Cuerpo Academico de Energia y Sustentabilidad-UP Chiapas, Tuxtla Gutierrez, Chiapas (Mexico)

    2007-10-15

    In this work, a computer simulation program was developed to determine the optimum operating conditions of an air conditioning system during the co-generation process. A 1 kW PEMFC was considered in this study with a chemical/electrical theoretical efficiency of 40% and a thermal efficiency of 30% applying an electrical load of 100%. A refrigeration-absorption cycle (RAC) operating with monomethylamine-water solutions (MMA-WS), with low vapor generation temperatures (up to 80 C) is proposed in this work. The computer simulation was based on the refrigeration production capacity at the maximum power capacity of the PEMFC. Heat losses between the fuel cell and the absorption air conditioning system at standard operating conditions were considered to be negligible. The results showed the feasibility of using PEMFC for cooling, increasing the total efficiency of the fuel cell system. (author)

  19. Rational use of energy in air conditioning equipment, through an appropriate selection of the main equipment; Uso racional de la energia en equipos de aire acondicionado, mediante la eleccion apropiada del equipo principal

    Energy Technology Data Exchange (ETDEWEB)

    Reyes Zuniga, Jose de Jesus; Herrera Ramos, Manuel [Instituto Mexicano del Petroleo (Mexico)

    1996-07-01

    This paper presents an analysis to diminish the consumption of energy in central air conditioning equipment through an appropriate selection of the equipment. The analysis shows the levels of security and toxicity of the refrigerant, the operational, constructive and economic advantages of the equipment, taking as reference the cooling demand and expenses of energy consumption, as well as the ecological impact derived from the use of the refrigerant. Finally, an economic analysis is presented, involving the expenses of the equipment, operation, maintenance, costs of the consumption of used fluids, et cetera. [Spanish] Uso racional de la energia en equipos de aire acondicionado, mediante la eleccion apropiada del equipo principal. Este trabajo presenta un analisis para disminuir el consumo de energia en los equipos centrales de aire acondicionado mediante la seleccion apropiada del equipo. El analisis muestra los niveles de seguridad y toxicidad del refrigerante, las ventajas operativas, constructivas y economicas del equipo, tomando como referencia la demanda de enfriamiento y gastos de consumo de energia, asi como el impacto ecologico derivado de su empleo del refrigerante. Finalmente, se presenta un analisis economico, involucrando los gastos del equipo, operacion, mantenimiento, costos de consumos de fluidos utilizados, etcetera.

  20. Evaluation of energy saving in pilot projects of window type air conditioning equipment in the domestic sector; Evaluacion del ahorro de energia en proyectos pilotos en equipos de aire acondicionado tipo ventana en el sector domestico

    Energy Technology Data Exchange (ETDEWEB)

    Duran Ramirez, Ricardo [Comision Nacional para el Ahorro de Energia, Mexico, D.F. (Mexico)

    2001-07-01

    The present work shows the energy saving when replacing low efficiency window type air conditioning equipment, for higher efficiency equipment, as well as the necessary parameters to identify the results obtained by the pilot projects of substitution of conventional equipment for other more efficient in the domestic sector. [Spanish] El presente trabajo muestra los ahorros de energia al sustituir equipos de aire acondicionado tipo ventana de baja eficiencia, por equipos de mayor eficiencia, asi como los parametros necesarios para identificar los resultados obtenidos, por los proyectos pilotos de sustitucion de equipos convencionales por otros mas eficientes en el sector domestico.

  1. Generation of equipment response spectrum considering equipment-structure interaction

    International Nuclear Information System (INIS)

    Lee, Sang Hoon; Yoo, Kwang Hoon

    2005-01-01

    Floor response spectra for dynamic response of subsystem such as equipment, or piping in nuclear power plant are usually generated without considering dynamic interaction between main structure and subsystem. Since the dynamic structural response generally has the narrow-banded shapes, the resulting floor response spectra developed for various locations in the structure usually have high spectral peak amplitudes in the narrow frequency bands corresponding to the natural frequencies of the structural system. The application of such spectra for design of subsystems often leads to excessive design conservatisms, especially when the equipment frequency and structure are at resonance condition. Thus, in order to provide a rational and realistic design input for dynamic analysis and design of equipment, dynamic equipment-structure interaction (ESI) should be considered in developing equipment response spectrum which is particularly important for equipment at the resonance condition. Many analytical methods have been proposed in the past for developing equipment response spectra considering ESI. However, most of these methods have not been adapted to the practical applications because of either the complexities or the lack of rigorousness of the methods. At one hand, mass ratio among the equipment and structure was used as an important parameter to obtain equipment response spectra. Similarly, Tseng has also proposed the analytical method for developing equipment response spectra using mass ratio in the frequency domain. This method is analytically rigorous and can be easily validated. It is based on the dynamic substructuring method as applied to the dynamic soil-structure interaction (SSI) analysis, and can relatively easily be implemented for practical applications without to change the current dynamic analysis and design practice for subsystems. The equipment response spectra derived in this study are also based on Tseng's proposed method

  2. Improved servicing equipment for steam generators

    International Nuclear Information System (INIS)

    Hedtke, James C.

    1998-01-01

    To help keep personnel exposure as low as reasonably achievable and reduce critical path outage time, most nuclear plants of PWR design in the USA are now using improved equipment to service their steam generators (SGs) during outages. Because of the success of this equipment in the USA, two Belgian plants and one English plant have purchased this equipment, and other nuclear plants in Europe are also considering procurement. The improved SG servicing equipment discussed in this paper discusses consists of nozzle dams, segmented multi-stud tensioner, primary manway cover handling tool set, shield door and fastener cleaner. This equipment is specifically designed for the individual plant application and can also be specified for replacement SG projects. All of the equipment can be used without modification of the existing SGs. (author)

  3. Energy saving by means of air conditioning equipment replacement and the household application of thermal insulation; Ahorro de energia electrica por reemplazo de equipos de aire acondicionado y aplicacion de aislamiento termico en viviendas

    Energy Technology Data Exchange (ETDEWEB)

    Peralta Solorio, Jose Luis [Fideicomiso para el Ahorro de la Energia (Mexico)

    2005-07-15

    An extension study of the Financing Program for Energy Saving looked for the evaluation of the electric energy saving potential obtained by the replacement of air conditioning equipment and the application of thermal insulation in 30 houses of two Mexican cities with warmth climate. In a joint effort with Comision Federal de Electricidad the consumption files of the users were analyzed and field measurements of electric demand and of refrigeration were made. As a following step the change of the refrigeration necessities derived from the application of thermal insulation were evaluated as well as the energy efficiency improvement obtained by the substitution of the air conditioning equipment and the favorable results obtained by the implementation of both measures - thermal insulation and change of air conditioning equipment in a joint form. This way, as a conclusion, the optimum sequence of application of these measures is revealed. [Spanish] Un estudio extension del Programa de Financiamiento para el Ahorro de Energia Electrica busco evaluar el potencial de ahorro de energia electrica alcanzado por el reemplazo de equipos de aire acondicionado y la aplicacion de aislamiento termico en 30 viviendas de dos ciudades mexicanas con clima calido. En un esfuerzo conjunto con la Comision Federal de Electricidad se analizaron los historiales de consumo de los usuarios y se efectuaron las mediciones de campo de demanda electrica y de refrigeracion. Como paso siguiente se valoro el cambio en las necesidades de refrigeracion derivado de la aplicacion de aislamiento termico al igual que la mejora en eficiencia energetica obtenida por la sustitucion de aire acondicionado y se identificaron los resultados favorecedores arrojados por la implementacion de ambas medidas -aislamiento termico y cambio de equipo de aire acondicionado- en forma conjunta. De esta manera, como conclusion, se devela la mas optima secuencia de aplicacion de estas medidas.

  4. Energy saving: optimal use of air conditioning equipment by means of the solar control; Ahorro de energia: uso optimo de los acondicionadores de aire mediante el control solar

    Energy Technology Data Exchange (ETDEWEB)

    Mejia D, David; Morillon G, David; Rodriguez V, Luis [Universidad Nacional Autonoma de Mexico (Mexico)

    2001-09-01

    In this article the evaluation of the solar heat gains through the transparent parts of a building (houses of social interest) is presented; with the purpose of determining the heat gains through windows during summer time and under the following conditions: without solar protection, with the use of eaves, solar breakers and, finally, with the use of both elements. With the determined percentage of the diminution of heat gains, the considered potential of energy saving in air conditioning was obtained that would be available if the houses were constructed with solar control. [Spanish] En este articulo se presenta la evaluacion de las ganancias de calor solar a traves de las partes transparentes de un edificio (viviendas de interes social); con el objeto de determinar las ganancias de calor a traves de ventanas para la epoca de verano y bajo las siguientes condiciones: sin proteccion solar, con el empleo de aleros, con quiebrasoles y, finalmente, con el empleo de ambos elementos. Con el porcentaje determinado de la disminucion de ganancias de calor, se obtuvo el potencial estimado de ahorro de energia en aire acondicionado que se tendria si las viviendas se construyen con control solar.

  5. A comparative study of different methods for the generation of tetra-n-butyl ammonium bromide clathrate hydrate slurry in a cold storage air-conditioning system

    International Nuclear Information System (INIS)

    Shi, X.J.; Zhang, P.

    2013-01-01

    Highlights: ► Four kinds of TBAB CHS generation methods are experimentally investigated. ► Accession of CHS into supercooled solution can be helpful to the generation. ► Higher flow rate results in higher energy efficiency of CHS generation. - Abstract: A cold storage air-conditioning system using tetra-n-butyl ammonium bromide (TBAB) clathrate hydrate slurry (CHS) as cold storage medium was built to investigate the high-efficiency method of TBAB CHS generation. In the present study, four kinds of different TBAB CHS generation methods were experimentally investigated and compared, and these methods included continuously cooling, turning off refrigerator while crystals appearing, supercooling release and accession of TBAB CHS into supercooled TBAB aqueous solution. The results showed that continuously cooling would lead to severe adhesion of crystal to the heat exchanger wall, and supercooling release took place with a big stochastic characteristic, hence the first and third method were concluded not reliable. Both the second and fourth methods could maintain the temperature of heat exchanger wall at a relatively higher level, therefore the crystal adhesion to the heat exchanger wall would be reduced significantly, which led to higher coefficient of performance (COP). In addition, accession of TBAB CHS into TBAB supercooled solution could shorten the time of supercooling release, resulting in about 21.8–35.4% shorter generation time than other methods. Moreover, the influence of flow rate on the CHS generation process was investigated, and the results showed that higher flow rate generally resulted in higher system COP

  6. Stage 1 performance qualification of heat-ventilation air-conditioning (HVAC) system for the manufacturing of Tc-99m Generator at Nuclear Malaysia

    International Nuclear Information System (INIS)

    Yen Ng; Noriah Jamal; Rehir Dahalan; Wan Anuar Wan Awang; Noraisyah Yusof; Shaharum Ramli; Jusnan Hashim; Ariff Hamzah; Wan Firdaus Wan Ishak; Yahaya Talib; Othman Mahmud; Asmah Mohibat; Shafii Khamis; Zulkifli Mohamed Hashim; Zakaria Ibrahim; Shaaban Kasim

    2007-01-01

    Manufacturing of Tc-99m generator is carried out in clean room Block 21 of Malaysian Nuclear Agency, which need to comply current Good Manufacturing Practice requirement. High-ventilation air conditioning (HVAC) is a new renovated system. It is a critical system for maintaining suitable temperature, relative humidity and pressure differential in the clean room. The objective of this paper is to present results on Stage 1 Performance Qualification (PQ) for HVAC. This PQ stage 1 was done from 7 February 2007 till 16 March 2007. Temperature, Relative Humidity and Pressure Differential for each compartment in the clean room was monitored twice daily. The Measurement of air-born particle count was done weekly. Settle plate for microbial test was also done weekly. The results were then analyzed and compared with the pre-determined specification. We found that temperature was within the specs, namely 24 +20 degree C. Relative humidity was less than 65%. Pressure differential shows variation, some compartments are below the specs namely 1-3 mm H 2 O. Air-born particle and microbial test also meet the requirement. The results show that all parameters meeting the specs excepts for the pressure differential for certain compartments are a bit low, but is sufficient to create proper air flow and not cause any risk of cross contamination. The existing HVAC system in the clean room is in compliance to the pre-determined specification. However, further improvement can be made by increasing the pressure differential between compartments. (Author)

  7. 光伏并网式家用空调系统性能的实验研究%Experimental Investigation on the Performance of Household Air Conditioning System with Grid-connected Photovoltaic Generation

    Institute of Scientific and Technical Information of China (English)

    金听祥; 徐笑锋

    2015-01-01

    With the base of traditional air conditioning system, the grid-connected photovoltaic household air conditioning sys-tem based on the solar photovoltaic power generation technology is designed in this paper. The power with the solar photovoltaic power generation technology is transformed into the household power of 220 V and 50 Hz by inverter. The household air condi-tioning system is then driven by the transformed power and national grid. The performance of the photovoltaic grid-connected household air conditioning system was tested by Enthalpy Difference Lab under the different power ( 100 W, 135 W and 185 W) of solar panels. The experimental results show that under normal cooling conditions, the average power consumption of the air conditioning system with the different power (100 W, 135 W and 185 W) of solar panels are 52 W, 78 W and 104 W lower than that of the traditional air conditioning system respectively. Similarly, energy efficiency ratios of the air conditioning system with the different power (100 W, 135 W and 185 W) of solar panels are 4. 2%, 5. 5% and 10. 2% lower than that of the tra-ditional air conditioning system respectively. Under heating mode, the average power consumption of the air conditioning system with the different power (100 W, 135 W and 185 W) of solar panels are 68 W, 84 W and 116 W lower than that of the tradi-tional air conditioning system, and the coefficients of performances are 6. 4%, 8% and 11% lower than that of the traditional air conditioning system. It can be concluded that the photovoltaic grid-connected household air conditioning system is feasible.%针对目前的家用空调系统,本文设计了一种以太阳能光伏发电技术为基础,与国家电网并网,共同驱动空调工作的系统,称为光伏并网式家用空调系统。利用光伏发电技术,通过逆变器将太阳能提供的电力转变为220 V、50 Hz家用电源,实现与市电电网的并网,来共同驱动空调运行。利用焓差实验室,

  8. Infrasonic waves and air-conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Hoenmann, W.

    1986-08-01

    This article is a critical investigation of the recently-suggested possibility that the infrasound generated by an air conditioning system (up to 2o kHz) may adversely affect the well-being of human beings. After an introductory explanation of the infrasonic wave band and the dependency of the sound pressure level on the frequency for decibel values of 20 to 100 (diagram), the relevant results of studies by various experts are quoted. It became apparent that the influence of the inaudible infrasound has been greatly overestimated, whereas audibility was underestimated. Inaudible infrasound was shown to be completely harmless. A number of frequency variation analysis diagrams of various residences (old building, new building) with audibility thresholds marked in. The measurement results discussed in more detail indicate that it is possible not to raise the basic noise level of an air conditioning system in the low-frequency range. Therein lies the actual acoustic chance for air conditioning: In an air-conditioned building, there is no need to ventilate by means of open windows, thereby letting in traffic noise, the nuisance value of which is beyond dispute. (HWJ).

  9. Flow in air conditioned rooms

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    1974-01-01

    Flow in air conditioned r ooms is examined by means of model experiments . The different gearnetries giving unsteady, steady three- dimensional and steady twodimensional flow are determined . Velacity profiles and temperature profiles are measured in some of the geometries. A numerical solution...... of the flow equations is demonstrated and the flow in air conditioned rooms in case of steady two dimensional flow is predi cted. Compari son with measured results is shown i n the case of small Archimedes numbers, and predictions are shown at high Archimedes numbers. A numerical prediction of f low and heat...

  10. Refrigeration and air-conditioning technology workshop

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, P. J.; Counce, D. M. [eds.

    1993-01-01

    The Alternative Fluorocarbon Environmental Acceptability Study (AFEAS), a consortium of fluorocarbon manufacturers, and the US Department of Energy (DOE) are collaborating on a project to evaluate the energy use and global warming impacts of CFC alternatives. The goal of this project is to identify technologies that could replace the use of CFCs in refrigeration, heating, and air-conditioning equipment; to evaluate the direct impacts of chemical emissions on global warming; and to compile accurate estimates of energy use and, indirect CO{sub 2} emissions of substitute technologies. The first phase of this work focused on alternatives that could be commercialized before the year 2000. The second phase of the project is examining not-in-kind and next-generation technologies that could be developed to replace CFCs, HCFCs, and HFCs over a longer period. As part of this effort, Oak Ridge National Laboratory held a workshop on June 23--25, 1993. The preliminary agenda covered a broad range of alternative technologies and at least one speaker was invited to make a brief presentation at the workshop on each technology. Some of the invited speakers were unable to participate, and in a few cases other experts could not be identified. As a result, those technologies were not represented at the workshop. Each speaker was asked to prepare a five to seven page paper addressing six key issues concerning the technology he/she is developing. These points are listed in the sidebar. Each expert also spoke for 20 to 25 minutes at the workshop and answered questions from the other participants concerning the presentation and area of expertise. The primary goal of the presentations and discussions was to identify the developmental state of the technology and to obtain comparable data on system efficiencies. Individual papers are indexed separately.

  11. Energy impact of indoor environmental policy for air-conditioned offices of Hong Kong

    International Nuclear Information System (INIS)

    Wong, L.T.; Mui, K.W.; Shi, K.L.

    2008-01-01

    Air-conditioned office buildings are one of the biggest energy consumers of electricity in developed cities in the subtropical climate regions. A good energy policy for the indoor environment should respond to both the needs of energy conservation and the needs for a desirable indoor healthy environment with a reduction in carbon dioxide (CO 2 ) generation. This study evaluates energy implications and the corresponding CO 2 generation of some indoor environmental policies for air-conditioned office buildings in the subtropical climate. In particular, the thermal energy consumption in an air-conditioned office building was evaluated by the heat gains through the building fabric, the transport of outdoor fresh air for ventilation, and the heat generated by the occupant and equipment in the space. With the Monte-Carlo sampling technique and the parameters from the existing office building stocks of Hong Kong, the energy consumption profiles of air-conditioned office buildings in Hong Kong were evaluated. Energy consumption profiles were simulated for certain indoor environmental quality (IEQ) policies on indoor air temperature and CO 2 concentration settings in the offices, with other building parameters remaining unchanged. The impact assessment and the regression models described in this study may be useful for evaluation of energy performances of IEQ policies. They will also be useful for the promotion of energy-saving measures in air-conditioned office buildings in Hong Kong. This study presented a useful source of references for policymakers, building professionals and end users to quantify the energy and environmental impacts due to an IEQ policy for air-conditioned office buildings

  12. Health effects of air conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Molina, C.; Caillaud, D.

    The air conditioning used in residential or commercial buildings (offices, hotels, sterile areas of hospitals, computer and electronics industries) is responsible for a certain number of well identified ailments which can be classified in three groups: infections (legionnaires'disease, ornithosis), allergies (mainly respiratory) eg. rhinitis, asthma, alveolitis but also Monday morning illness or humidifier fever, various functional disorders grouped under the name Sick Building Syndrome. To avoid these problems, a certain number of recommendations may be made. They concern: installation of air conditioning, humidification which is the cause of bacterial and fungal contamination, filtration, monitoring of the installation by qualitative and quantitative measurements, maintenance. The legal problems relating to these illnesses, the responsibility for which is ultimately laid at the door of the installers, should also be mentioned. Allergies are recognized to be of professional origin in Table 66 of allergic illnesses issued by the Social Security.

  13. Ventilation-air conditioning system

    International Nuclear Information System (INIS)

    Kubokoya, Takashi.

    1991-01-01

    Heretofore, in ventilation-air conditioning systems in a nuclear power plant, exhaust gases from each of the ventilation-air conditioning systems of a reactor building, a turbine building, a waste processing building are joined and they are released into atmosphere from the top of a high main exhaustion stack. In order to build such a high main exhaustion stack, a considerable construction cost is required and, in addition, there is a worry of lacking balance with surrounding scenery. Then, in the present invention, exhaust gases are heated by waste heat in a turbine during their introduction from the ventilation-air conditioning facility in the building of a power plant to the main exhaust stack. With such a constitution, since the exhaust gases are heated and their temperature is elevated, they uprise by natural convection when they are released from the top of the main exhaustion stack to the atmosphere. Accordingly, they are released to a level higher than the conventional case in view of the volume of the blower which sends the exhaust gases under pressure, to diffuse them to the atmosphere more sufficiently compared with a conventional case. Further, the height of the main exhaustion stack can be reduced, enabling to minimize the cost for moving the blower. (T.M.)

  14. Equipment transporter for nuclear steam generator

    International Nuclear Information System (INIS)

    Hayes, L.R.

    1987-01-01

    A transporter is described for use in a steam generator of a nuclear power installation. The generator is essentially a heat exchanger having a vertically extended shell. Across the lower portion extends a horizontal tube sheet having an upper surface which supports a bundle of vertically extending tubes forming a limited annular space with the inside of the shell wall and the upper surface. An opening of limited dimensions through the shell wall gains manual access to the limited annular space. The transporter has means for locating and removing solid debris from the upper surface of the tube sheet in the annular space and has a means for assembly and disassembly of the transporter so that it may be manually passed through the shell opening to and from a position on the upper surface of the tube sheet in the annular space. The transporter includes: a body; at least three wheels mounted on the body for engaging the upper surface of the tube sheet; a first motor mounted on the body drivingly connected to the wheels for moving the transporter along the upper surface of the tube sheet in the annular space; a remotely operated means on the body for locating solid debris on the upper surface of the tube sheet; and means for securing and removing solid debris on the upper surface of the tube sheet located by the means for locating

  15. Solar air-conditioning. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    Within the 3rd International Conference on solar air-conditioning in Palermo (Italy) at 30th September to 2nd October, 2009 the following lectures were held: (1) Removal of non-technological barriers to solar cooling technology across Southern European islands (Stefano Rugginenti); (2) The added economic and environmental value of solar thermal systems in microgrids with combined heat and power (Chris Marney); (3) Australian solar cooling interest group (Paul Kohlenbach); (4) Designing of a technology roadmap for solar assisted air conditioning in Austria (Hilbert Focke); (5) Solar cooling in the new context of renewable policies at European level (Raffaele Piria); (6) Prototype of a solar driven steam jet ejector chiller (Clemens Pollerberg); (7) New integrated solar air conditioning system (Joan Carlos Bruno); (8) Primary energy optimised operation of solar driven desiccant evaporative cooling systems through innovative control strategies; (9) Green chiller association (Uli Jakob); (10) Climate Well {sup registered} (Olof Hallstrom); (11) Low capacity absorption chillers for solar cooling applications (Gregor Weidner); (12) Solar cooling in residential, small scale commercial and industrial applications with adsorption technology (Walter Mittelbach); (13) French solar heating and cooling development programme based on energy performance (Daniel Mugnier); (14) Mirrox fresnel process heat collectors for industrial applications and solar cooling (Christian Zahler); (15) Modelling and analyzing solar cooling systems in polysun (Seyen Hossein Rezaei); (16) Solar cooling application in Valle Susa Italy (Sufia Jung); (17) Virtual case study on small solar cooling systems within the SolarCombi+Project (Bjoern Nienborg); (18) Design of solar cooling plants under uncertainty (Fernando Dominguez-Munoz); (19) Fast pre-design of systems using solar thermally driven chillers (Hans-Martin Henning); (20) Design of a high fraction solar heating and cooling plant in southern

  16. The Future of Air Conditioning for Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Goetzler, William [Navigant Consulting, Burlington, MA (United States); Guernsey, Matt [Navigant Consulting, Burlington, MA (United States); Young, Jim [Navigant Consulting, Burlington, MA (United States); Fujrman, Jay [Navigant Consulting, Burlington, MA (United States); Abdelaziz, Amar [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-07-01

    BTO works with researchers and industry to develop and deploy technologies that can substantially reduce energy consumption and greenhouse gas (GHG) emissions in residential and commercial buildings. Air conditioning systems in buildings contribute to GHG emissions both directly through refrigerant emissions, as well as indirectly through fossil fuel combustion for power generation. BTO promotes pre-competitive research and development on next-generation HVAC technologies that support the phase down of hydrofluorocarbon (HFC) production and consumption, as well as cost-effective energy efficiency improvements. DOE provides, with this report, a fact-based vision for the future of A/C use around the world. DOE intends for this vision to reflect a broad and balanced aggregation of perspectives. DOE brings together this content in an effort to support dialogue within the international community and help keep key facts and objectives at the forefront among the many important discussions.

  17. New excitation equipment for 220 MW generators in Kozloduy NPP

    International Nuclear Information System (INIS)

    Tomerlin, D.

    2001-01-01

    Rehabilitation on the excitation equipment for Generator 5, Reactor Unit 3, in Kozloduy NPP was completed in November 2000. ABB's Static Excitation System based on UNITROL 5000 technology has been chosen by the Bulgarian National Utility and Kozloduy NPP to substitute the original Russian excitation system equipment with electro-magnetic voltage regulators. The substitution is in a rehabilitation package of four excitation system equipment for Generator 5 and 6 of Reactor Unit 3 and Generator 7 and 8 of Reactor Unit 4 after a short overview of the original excitation system this paper describes the new Static Excitation System UNITROL 5000 including configuration with block diagram, its main features and merits such as modes of operation, limiter, special control functions and diagnostic facilities. Furthermore, new facilities, which are implemented in UNITROL 5000, such as dynamic current distribution among the thyristors working in parallel as well as the start-up from the residual magnetism are mentioned. Special functions including a so-called free-running mode of operation and automatic change over sequence from new excitation system to the stand-by excitation system, which is DC exciter machine, are described. Some records of the transient responses performed during the commissioning and a photograph of a manufactured system are provided. (author)

  18. 'O{sub 2} World' in Berlin. A multifunctional arena of the fifth generation. Air conditioning for all types of events; 'O{sub 2} World' in Berlin. Eine Multifunktionsarena der 5. Generation. Die Klimaanlage wird zum Stimmungsmacher

    Energy Technology Data Exchange (ETDEWEB)

    Krischausky, Lutz [Wolf GmbH, Mainburg (Germany)

    2009-07-01

    The Anschutz Entertainment Group invested about 165 million Euros in their new multifunctional arena 'O{sub 2} World' in Berlin. The arena has 17,000 seats and is Germany's most state-of-the-art arena building. It can be converted over night into an ice arena, a basketball stadium, a concert hall, or an opera house as desired. The technical facilities are equipped with so-called set-ups that ensure that air conditioning systems follow a specific scenario for each type of event. (orig.)

  19. Heating, ventilating, and air-conditioning applications

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    This book covers: Comfort air conditioning and heating of residences: Space HVAC systems; Industrial and special air conditioning and ventilation for nuclear facilities, and for mines; Energy sources, such as Geothermal energy, solar utilization, and energy resources; Building operation and maintenance; energy management, and Thermal storage

  20. Fungal colonization of air-conditioning systems

    Directory of Open Access Journals (Sweden)

    Ljaljević-Grbić Milica

    2008-01-01

    Full Text Available Fungi have been implicated as quantitatively the most important bioaerosol component of indoor air associated with contaminated air-conditioning systems. rarely, indoor fungi may cause human infections, but more commonly allergenic responses ranging from pneumonitis to asthma-like symptoms. From all air conditioner filters analyzed, 16 fungal taxa were isolated and identified. Aspergillus fumigatus causes more lethal infections worldwide than any other mold. Air-conditioning filters that adsorb moisture and volatile organics appear to provide suitable substrates for fungal colonization. It is important to stress that fungal colonization of air-conditioning systems should not be ignored, especially in hospital environments.

  1. SAT's infrared equipment using second-generation detectors

    Science.gov (United States)

    Siriex, Michel B.

    1995-09-01

    In 1982 SAT proposed for the first time a second generation detector in the design of FLIRs for the TRIGAT program, since then different types of IR equipment have been developed on the basis of this technology: (1) An infra-red seeker for the MICA missile. (2) Three types of IRST: VAMPIR MB for naval applications, SIRENE for the Army and OSF for the Rafale aircraft. (3) Three thermal imagers: Condor 1 for the mast mounted sight equipping the long range anti tank system, Tiger installed on the sight of the medium range antitank system, and Condor 2 for the pilot sight of the TRIGAT French-German helicopter. Infra-red detectors are MCT IR-CCD focal plane arrays developed by SOFRADIR with the objective of the best standardization possible in spite of different configurations and specifications for each program. In this paper, we intend to present the main features of this technology for these programs and the advantages obtained by comparison with the first generation in terms of performance. Industrialization of these products is starting now, and a specific effort has been made to standardize the components, especially the driving and read out electronics. A set of ASICs has been developed to make compact detection modules including a detector in his dewar, a cooling machine, and a proximity electronic.

  2. Accident alarm equipment for steam generator, especially liquid sodium heated steam generator

    International Nuclear Information System (INIS)

    Matal, O.; Jung, J.; Banovec, J.

    1982-01-01

    The alarm equipment consists of a system of sensors mounted onto the steam generator and its accessories. Each of the sensors is used for a different accident characteristic, such as the flow of sodium, the acoustic spectrum, the concentration of hydrogen in sodium. The system of sensors is connected to the common accident alarm system. The equipment will not issue the alarm signal if it receives a message from only one sensor, only when the message is confirmed from other sensors. This excludes false alarm. (M.D.)

  3. Alternatives Generation Analysis Long Length Contaminated Equipment Removal System Storage

    International Nuclear Information System (INIS)

    BOGER, R.M.

    1999-01-01

    Major pieces of Characterization sampling equipment are currently stored outdoors. This includes the Long Length Contaminated Equipment receiver trailer and transportation trailer. A decision is required to determine the preferred alternative for facilities to store and maintain this equipment. The Long Length Contaminated Equipment Removal System (LLCERS) consists of many tools, mechanisms, and controllers currently stored in various locations. Much of this equipment should be protected from the elements while being stored. Some of the LLCERS equipment should be protected with some kind of roof cover. This decision analysis is to determine the best alternative for weather protection for the large equipment requiring a cover. Additional details are included in Sections 2.0 and 5.0. Key assumptions used in this analysis are detailed in Section 3.2

  4. Air conditioning systems to clean radioactive air

    International Nuclear Information System (INIS)

    Ganz, G.

    1987-01-01

    The author reports a study by the Institutes fuer Klimatechnik and Umweltschutz Giessen that shows that air conditioning systems not only make the atmosphere more comfortable, they also extract dust particles. This cleaning action is also valid for radioactively contaminated air. (G.T.H./Auth.)

  5. Air Conditioning and Refrigeration. Book One.

    Science.gov (United States)

    Wantiez, Gary W.

    Designed to provide students with the basic skills for an occupation in air conditioning and refrigeration, this curriculum guide includes seven major areas, each consisting of one or more units of instruction. These areas and their respective units are titled as follows: Orientation (history and development, and job opportunities), Safety…

  6. Performance advancement of solar air-conditioning through integrated system design for building

    International Nuclear Information System (INIS)

    Fong, K.F.; Lee, C.K.

    2014-01-01

    This study is to advance the energy performance of solar air-conditioning system through appropriate component integration from the absorption refrigeration cycle and proper high-temperature cooling. In the previous studies, the solar absorption air-conditioning using the working pair of water – lithium bromide (H 2 O–LiBr) is found to have prominent primary energy saving than the conventional compression air-conditioning for buildings in the hot-humid climate. In this study, three integration strategies have been generated for solar cooling, namely integrated absorption air-conditioning; integrated absorption-desiccant air-conditioning; and integrated absorption-desiccant air-conditioning for radiant cooling. To realize these ideas, the working pair of ammonia – water (NH 3 –H 2 O) was used in the absorption cycle, rather than H 2 O–LiBr. As such, the evaporator and the condenser can be separate from the absorption refrigeration cycle for the new configuration of various integrated design alternatives. Through dynamic simulation, the year-round primary energy saving of the proposed integration strategies for solar NH 3 –H 2 O absorption air-conditioning systems could be up to 50.6% and 25.5%, as compared to the conventional compression air-conditioning and the basic solar H 2 O–LiBr absorption air-conditioning respectively. Consequently, carbon reduction of building air-conditioning can be achieved more effectively through the integrated system design in the hot and humid cities. - Highlights: • Three integration strategies, IAAU, IADAU and IADAU-RC, are proposed to advance solar air-conditioning. • NH 3 –H 2 O is adopted for absorption refrigeration instead of H 2 O–LiBr. • Separate evaporator and condenser, desiccant cooling and radiant cooling are designed for IADAU-RC. • IADAU-RC can have 50.6% primary energy saving against the conventional air-conditioning

  7. [Microbial air purity in hospitals. Operating theatres with air conditioning system].

    Science.gov (United States)

    Krogulski, Adam; Szczotko, Maciej

    2010-01-01

    The aim of this study was to show the influence of air conditioning control for microbial contamination of air inside the operating theatres equipped with correctly working air-conditioning system. This work was based on the results of bacteria and fungi concentration in hospital air obtained since 2001. Assays of microbial air purity conducted on atmospheric air in parallel with indoor air demonstrated that air filters applied in air-conditioning systems worked correctly in every case. To show the problem of fluctuation of bacteria concentration more precisely, every sequences of single results from successive measure series were examined independently.

  8. Central Air-Conditioning Plant (CAP) extension

    International Nuclear Information System (INIS)

    Shetty, P.S.; Kaul, S.K.; Mishra, H.

    2017-01-01

    Central Air-Conditioning Plant (CAP) and its associated chilled water network of BARC is one among the largest central plants in India for such application. The plant was planned in 1960s to cater to the air-conditioning and process water requirements of laboratories, workshops and buildings spread over a distance of 1.5 Km in three directions from CAP through underground network of chilled water pipelines. The plant was designed for a total capacity of 6600 TR. The present installed capacity of the plant is 7250 TR. The connected load at present is 9800 TR. After the XII plan capacity will be augmented to 7650 TR. The connected load is expected to cross 11,000 TR after the commissioning of new Engg. Halls 9, 10 and 11

  9. Air conditioning with small power gas appliances

    International Nuclear Information System (INIS)

    Canci, Franco

    1997-01-01

    This article describes research and test activities on small power air conditioning appliances for residential use carried out in the United States, Japan and Europe. The absorption technology aims at the following objectives: to develop appliances requiring reduced maintenance and having a size comparable with electric units of the same output; to reduce production costs and therefore the final prince by adopting special manufacturing technologies such as welded plate exchangers; to obtain appliances which operate both in summer and winter ( as heat pumps), allowing to minimize management and installation costs in southern European climates. The final aim is to offer the customer one appliance only for the following purposes: hot water production for sanitary use, water refrigeration for summer air conditioning, hot water production production for winter heating. This kind of appliance should have management and maintenance costs similar to current individual boilers

  10. Thermo economical evaluation of retrofitting strategies in air conditioning systems

    Energy Technology Data Exchange (ETDEWEB)

    Tribess, Arlindo; Fiorelli, Flavio Augusto Sanzogo; Hernandez Neto, Alberto [Sao Paulo Univ., SP (Brazil). Escola Politecnica. Dept. de Engenharia Mecanica]. E-mail: atribess@usp.br; fiorelli@usp.br; ahneto@usp.br

    2000-07-01

    In a building project, several subsystems are designed, among them the air conditioning system. Electrical energy consumption profiles show that this subsystem is responsible for 40 to 50% of total consumption in a commercial building. Besides the study of technical aspects that should be considered in order to assure the thermal comfort of the occupants as well the temperature and humidity conditions for an efficient equipment operation, an economical evaluation of this subsystem should be also made. In retrofit projects, the economical aspect is also critical for such projects in order to assure bigger efficiency in an economically attractive way. This paper analyses some strategies that might be adopted in retrofitting an air conditioning system installed in a commercial building with mixed occupation. By mixed we mean that some floors have a typical office occupation profile and other floors are mainly occupied by electronic equipment. This analysis includes both technical and economical evaluation. The proposed solutions performance are compared to the old system, which allows to verify the retrofitting impact in energy consumption reduction and its economical feasibility. (author)

  11. Air conditioning for data processing system areas

    Directory of Open Access Journals (Sweden)

    Hernando Camacho García

    1996-09-01

    Full Text Available The appropiate selection of air conditioners for data processing system areas requires the knowledge of the environmental desing conditions, the air conditioning systems succssfully used computer and the cooling loads to handle. This work contains information about a wide variety of systems designed for computer room applications. a complete example of calculation to determine the amount of heat to be removed for satisfactory operation, is also included.

  12. Small photovoltaic setup for the air conditioning system

    Science.gov (United States)

    Masiukiewicz, Maciej

    2017-10-01

    The increasing interest in air conditioning systems for residential applications in Poland will certainly increase the demand for electricity during the summer period. Due to this fact a growing interest in solutions that help to lower the electricity consumption in this sector is observed. The problem of increased energy demand for air conditioning purposes can be solved by transfer the consumption of electricity from the grid system to renewable energy sources (RES). The greatest demand for cooling occurs during the biggest sunlight. This is the basis for the analysis of technical power system based on photovoltaic cells (PV) to power the split type air conditioner. The object of the study was the commercial residential airconditioning inverter units with a capacity of 2.5kW. A network electricity production system for their own use with the possibility of buffering energy in batteries (OFF-GRID system). Currently, on the Polish market, there are no developed complete solutions dedicated to air conditioning systems based on PV. In Poland, solar energy is mainly used for heat production in solar collectors. The proposed solution will help to increase the popularity of PV systems in the Polish market as an alternative to other RES. The basic conclusion is that the amount of PV energy generated was sufficient to cover the daily energy requirement of the air conditioner.

  13. Small photovoltaic setup for the air conditioning system

    Directory of Open Access Journals (Sweden)

    Masiukiewicz Maciej

    2017-01-01

    Full Text Available The increasing interest in air conditioning systems for residential applications in Poland will certainly increase the demand for electricity during the summer period. Due to this fact a growing interest in solutions that help to lower the electricity consumption in this sector is observed. The problem of increased energy demand for air conditioning purposes can be solved by transfer the consumption of electricity from the grid system to renewable energy sources (RES. The greatest demand for cooling occurs during the biggest sunlight. This is the basis for the analysis of technical power system based on photovoltaic cells (PV to power the split type air conditioner. The object of the study was the commercial residential airconditioning inverter units with a capacity of 2.5kW. A network electricity production system for their own use with the possibility of buffering energy in batteries (OFF-GRID system. Currently, on the Polish market, there are no developed complete solutions dedicated to air conditioning systems based on PV. In Poland, solar energy is mainly used for heat production in solar collectors. The proposed solution will help to increase the popularity of PV systems in the Polish market as an alternative to other RES. The basic conclusion is that the amount of PV energy generated was sufficient to cover the daily energy requirement of the air conditioner.

  14. Ventilation and air-conditioning system for PWR nuclear power plant

    International Nuclear Information System (INIS)

    Ohmoto, Kenji

    1987-01-01

    This report outlines the ventilation and air conditioning facilities for PWR nuclear power plant as well as design re-evaluation and optimization of ventilation and air-conditioning. The primary PWR installations are generally housed in the nuclear reactor building, auxiliary buildings and control building, which are equipped with their own ventilation and air-conditioning systems to serve for their specific purposes. A ventilation/air-conditioning system should be able to work effectively not only for maintaining the ordinary reactor operation but also for controlling the environmental temperature in the event of an accident. Designing of a ventilation/air-conditioning system relied on empirical data in the past, but currently it is performed based on information obtained from various analyses to optimize the system configuration and ventilation capacity. Design re-evaluation of ventilation/air-conditioning systems are conducted widely in various areas, aiming at the integration of safety systems, optimum combination of air-cooling and water-cooling systems, and optimization of the ventilation rate for controlling the concentrations of radioactive substances in the atmosphere in the facilities. It is pointed out that performance evaluation of ventilation/air-conditioning systems, which has been conducted rather macroscopically, should be carried out more in detal in the future to determine optimum air streams and temperature distribution. (Nogami, K.)

  15. Data characteristic analysis of air conditioning load based on fast Fourier transform

    Science.gov (United States)

    Li, Min; Zhang, Yanchi; Xie, Da

    2018-04-01

    With the development of economy and the improvement of people's living standards, air conditioning equipment is more and more popular. The influence of air conditioning load for power grid is becoming more and more serious. In this context it is necessary to study the characteristics of air conditioning load. This paper analyzes the data of air conditioning power consumption in an office building. The data is used for Fast Fourier Transform by data analysis software. Then a series of maps are drawn for the transformed data. The characteristics of each map were analyzed separately. The hidden rules of these data are mined from the angle of frequency domain. And these rules are hard to find in the time domain.

  16. Nuclear power generating station equipment qualification method and apparatus

    International Nuclear Information System (INIS)

    Fero, A.H.; Potochnik, L.M.; Riling, R.W.; Semethy, K.F.

    1990-01-01

    This patent describes a method of monitoring an object piece of qualified equipment in a nuclear power plant. It comprises providing a first passive mimic means for mimicking the effect of radiation received by the object piece on the object piece; providing a second mimic means for mimicking the effect of a thermal history of the object piece on the object piece and mounting the first passive mimic means and the second mimic means in close proximity to the object piece

  17. Performance Evaluation of Photovoltaic Solar Air Conditioning

    Directory of Open Access Journals (Sweden)

    Snegirjovs A.

    2016-12-01

    Full Text Available Information on the electrical-driven solar air conditioning (SAC is rather scanty. A considerable body of technical data mostly concerns large-scale photo-voltaic solar air conditioning (PV-SAC systems. Reliable information about the energy output has arisen only in recent years; however, it is still not easily accessible, and sometimes its sources are closed. Despite these facts, solar energy researchers, observers and designers devote special attention to this type of SAC systems. In this study, performance evaluation is performed for the PV-SAC technology, in which low-power (up to 15 kWp of cooling power on average systems are used. Such a system contains a PV electric-driven compression chiller with cold and heat sensible thermal storage capacities, and a rejected energy unit used for preheating domestic hot water (DHW. In a non-cooling season, it is possible to partly employ the system in the reverse mode for DHW production. In this mode, the ambient air serves as a heat source. Besides, free cooling is integrated in the PV-SAC concept.

  18. Performance Evaluation of Photovoltaic Solar Air Conditioning

    Science.gov (United States)

    Snegirjovs, A.; Shipkovs, P.; Lebedeva, K.; Kashkarova, G.; Migla, L.; Gantenbein, P.; Omlin, L.

    2016-12-01

    Information on the electrical-driven solar air conditioning (SAC) is rather scanty. A considerable body of technical data mostly concerns large-scale photo-voltaic solar air conditioning (PV-SAC) systems. Reliable information about the energy output has arisen only in recent years; however, it is still not easily accessible, and sometimes its sources are closed. Despite these facts, solar energy researchers, observers and designers devote special attention to this type of SAC systems. In this study, performance evaluation is performed for the PV-SAC technology, in which low-power (up to 15 kWp of cooling power on average) systems are used. Such a system contains a PV electric-driven compression chiller with cold and heat sensible thermal storage capacities, and a rejected energy unit used for preheating domestic hot water (DHW). In a non-cooling season, it is possible to partly employ the system in the reverse mode for DHW production. In this mode, the ambient air serves as a heat source. Besides, free cooling is integrated in the PV-SAC concept.

  19. Electrically nonconductive shield for electric equipment generating ionizing radiation

    International Nuclear Information System (INIS)

    Aitken, D.

    1979-01-01

    As a radiation protection shield there is proposed a nonconductive shield fabricated from epoxides or other plastics material and containing finely dispersed radiation absorbing metal. It is to be designed in such a way that it lies in the range of a high electric gradient in the equipment, close to the radiation-producing component. As suitable metals there are mentioned tin, tungsten, and lead resp. their oxides. As an example there is used an X-ray shielding. (RW) 891 RW/RW 892 MKO [de

  20. Production and exploitation of thermoelectric air conditioning systems for vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Dudnik, Vladimir [Conditioner Ltd, Gagarin (Russian Federation); Skipidarov, Sergey [SCTB NORD, Moskau (Russian Federation); Rapp, Axel [Quick-Ohm Kupper und Co. GmbH, Wuppertal-Cronenberg (Germany)

    2011-07-01

    In the paper more than 10-year experience of thermoelectric devices batch manufacturing is described for the field of their obvious advantages. This field of application includes thermoelectric air conditioning systems which have shown their competitive advantage when used in vehicles of elevated vibration where compressor equipment application is difficult because of leakage of refrigerant. Energy characteristics of air conditioners for tractors, excavators, tanks, locomotive driver's cabins and cranes are described. Thermoelectric (TE) air conditioners mechanical test data as well as operation experience in vehicles are presented. It is shown that consumption of tellurium, which is a strategic component for thermoelectric materials manufacturing, may be lowered to 40 grams per 1 kW of cooling. (orig.)

  1. The new generation of detection and identification equipment

    International Nuclear Information System (INIS)

    Schultz, F.; Guerin, M.; Fort, Ph.

    2009-01-01

    The authors address the highly sensitive detection issue with real time identification of the risk nature, a problem which occurs every time a source is only fleetingly present (a pedestrian, a vehicle or an object on a conveyor belt passing by). They briefly present a range of instruments specially designed for this purpose, the SPIR-Ident instruments. These equipment use one or several large sensors, digital multichannel analyzers (one per sensor) and neutron and gamma measurements. Spectra are continuously processed, stabilized, linearized and normalized, and finally analyzed by an algorithm. The authors evoke the performance characterization and a return on experience after a 6 month-use for the control of passengers and luggage in airport

  2. Vapor generator equipped with a migrant body trapping device

    International Nuclear Information System (INIS)

    Pascal, Y.

    1994-01-01

    In a nuclear plant vapor generator, a device is foreseen to prevent objects coming from dryers, further to assembly, to subsequent interventions or to a fortuitous removal when operating, from coming jam between generator tubes. This device, which for example looks like a grid, is put above an horizontal plate to which are fixed the high ends of the pipes containing the cyclone separators. It determines crossings whose higher dimensions are lower to the minimal gap separating the tubes. (Author). 2 figs., 3 refs

  3. Universal Authenticated Item Monitoring System (AIMS) second generation equipment

    International Nuclear Information System (INIS)

    Schoeneman, J.L.; Baumann, M.J.; Fox, L.J.; Jenkins, C.D.; Perlinsk, A.W.

    1992-01-01

    Sandia National Laboratories (SNL) is in the final stages of developing a Universal Authenticated Item Monitoring System (AIMS). When completed, AIMS will provide applicable agencies in the US government, and those in the International arena, with a secure and convenient method of monitoring the physical status of selected items. The benefit derived from this development activity will be the commercial availability of an item monitoring system with the capability for ''quick set-up'' monitoring, as well as long-term unattended monitoring. The AIMS includes a variety of sensors, a robust and authenticated radio frequency (RF) communication link, a Receiver Processing Unit (RPU), and an inspector-friendly personal computer (PC) interface for collecting, sorting, viewing and archiving pertinent event histories. The system will provide the capability to monitor selected items in a real-time mode, a remotely interrogated mode, and a stand-alone, unattended data collection mode. The sensor suite under development includes advanced motion sensors, interior volumetric intrusion sensors, Re-usable, In-situ Verifiable Authenticated (RIVA) fiber-optic seal sensors, generic utility sensors (to accommodate contact closure inputs), and radiation and environmental sensors. A new generation authentication algorithm recently has been developed that provides a high degree of system security 121. The AIMS has potential safeguards applications in the areas of arms control and treaty verification military asset control, International Atomic Energy Agency (IAEA) and Euratom safeguards verification activities, as well as domestic nuclear safeguard activities. Commercial applications could include high-value inventory control and security systems. This paper describes the second-generation AIMS along with its recently expanded sensor suite and enhanced data collection capabilities

  4. Evaluation of Rankine cycle air conditioning system hardware by computer simulation

    Science.gov (United States)

    Healey, H. M.; Clark, D.

    1978-01-01

    A computer program for simulating the performance of a variety of solar powered Rankine cycle air conditioning system components (RCACS) has been developed. The computer program models actual equipment by developing performance maps from manufacturers data and is capable of simulating off-design operation of the RCACS components. The program designed to be a subroutine of the Marshall Space Flight Center (MSFC) Solar Energy System Analysis Computer Program 'SOLRAD', is a complete package suitable for use by an occasional computer user in developing performance maps of heating, ventilation and air conditioning components.

  5. Air conditioning sector marketing. Situazione nel settore del condizionamento dell'aria

    Energy Technology Data Exchange (ETDEWEB)

    Wurm, J.; Biederman, R. (Institute of Gas Technology, Chicago, IL (United States))

    1993-03-01

    Predictions are that the space heating ventilation and air conditioning equipment sector will undergo significant expansion in the coming decade. Substantial technology inputs will be required to make new equipment conform to standards on energy efficiency and environmental compatibility, and strong competition in this sector will force equipment designers to seek low energy cost solutions. The European energy price situation is expected to favour the use of reversible gas heat pumps in space HVAC systems for buildings. New environmental regulations, especially those governing refrigerant typology, indoor air pollution and thermal comfort in office buildings, should also help to increase demand for new technologically advanced equipment conforming with international standards.

  6. Air conditioning device for reactor buildings

    International Nuclear Information System (INIS)

    Kikuchi, Shiro.

    1982-01-01

    Purpose: To decrease the opening areas of pipe lines for an air conditioning device at the portions passing through the shielding walls of a reactor building for a FBR type reactor, as well as reduce the size of the building. Constitution: Airs in the building for containing reactor are liquefied in an air liquefying mechanism. The liquefied airs are sent by way of pipe lines to each of evaporators, wherein each of the chambers are cooled because of latent heat of evaporation and evaporated airs are released to each of the chambers. The airs released to each of the chambers are collected into an exhaust chamber and sent by way of a duct to the air liquefying mechanism and liquefied again. Since the volume of the liquefied airs may be smaller than the amount conventionally required for usual cooled airs, the pipe lines passing through the shielding walls of the building can be of smaller diameter. This can decrease the opening areas of the pipe lines at the portions passing through the walls of the shieldings and, since the opening areas are smaller, the structure of the radiation shieldings can be simplified in these portions. Further, since the space of the pipe lines in the building is reduced extremely, the size of the building can be reduced. (Moriyama, K.)

  7. Smart Sensors Enable Smart Air Conditioning Control

    Directory of Open Access Journals (Sweden)

    Chin-Chi Cheng

    2014-06-01

    Full Text Available In this study, mobile phones, wearable devices, temperature and human motion detectors are integrated as smart sensors for enabling smart air conditioning control. Smart sensors obtain feedback, especially occupants’ information, from mobile phones and wearable devices placed on human body. The information can be used to adjust air conditioners in advance according to humans’ intentions, in so-called intention causing control. Experimental results show that the indoor temperature can be controlled accurately with errors of less than ±0.1 °C. Rapid cool down can be achieved within 2 min to the optimized indoor capacity after occupants enter a room. It’s also noted that within two-hour operation the total compressor output of the smart air conditioner is 48.4% less than that of the one using On-Off control. The smart air conditioner with wearable devices could detect the human temperature and activity during sleep to determine the sleeping state and adjusting the sleeping function flexibly. The sleeping function optimized by the smart air conditioner with wearable devices could reduce the energy consumption up to 46.9% and keep the human health. The presented smart air conditioner could provide a comfortable environment and achieve the goals of energy conservation and environmental protection.

  8. A 'double-effect' tri-generation system ensures the air-conditioning of the CNES building in Toulouse; Une trigeneration ''double effet'' assure la climatisation des locaux du CNES a Toulouse

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2003-02-01

    A new type of tri-generation plant has been set up at the French national centre of space studies (CNES) in Toulouse (SW France) for the joint production of heat, coldness and electric power. Beside its high operational efficiency, this plant presents interesting energy and use flexibilities combined with low environmental impacts. (J.S.)

  9. The application of gas ejector for road transport air conditioning system

    Science.gov (United States)

    Sumeru, Nasution, Henry; Ani, Farid Nasir

    2012-06-01

    The depletion of fossil fuel supply requires fuel and energy saving in energy utilization system. Therefore, these required the development of new and efficient technologies as to reduce fuel consumption especially in air conditioning of road vehicles. Currently, the air conditioning for road vehicles uses vapor compression system. Although the vapor compression system has high COP, the compressor is driven by vehicle engines, which take additional fuel consumption when the air conditioning system is in operation. In this study, the waste heat of radiator drives the ejector refrigeration for air conditioning. Although the ejector refrigeration system has low COP, the use of heat driven air conditioning will reduce the fuel consumption as compared with conventional system. This is because the systems do not use the mechanical engine load. The analysis of this study is based on the ejector refrigeration system using natural refrigerant (isobutene). The evaporation temperature is 10°C, condensation temperature is 35°C, generator temperature is 90°C with ejector isentropic efficiency of 0.7, and the COP system is 0.25. The heat released by the radiator of typical small road vehicles is between 60 to 100 kW and if the generator absorbs 20% of the heat, the heat contained in the generator is 12 to 20 kW. When the ejector air conditioning system has a COP 0.25, it will generate cooling capacity between 3 to 5 kW, compared with the conventional air conditioning of similar vehicles, which is approximately 2 to 4.4 kW.

  10. Exergy analysis of heating, refrigerating and air conditioning methods and applications

    CERN Document Server

    Dincer, Ibrahim

    2015-01-01

    Improve and optimize efficiency of HVAC and related energy systems from an exergy perspective. From fundamentals to advanced applications, Exergy Analysis of Heating, Air Conditioning, and Refrigeration provides readers with a clear and concise description of exergy analysis and its many uses. Focusing on the application of exergy methods to the primary technologies for heating, refrigerating, and air conditioning, Ibrahim Dincer and Marc A. Rosen demonstrate exactly how exergy can help improve and optimize efficiency, environmental performance, and cost-effectiveness. The book also discusses the analysis tools available, and includes many comprehensive case studies on current and emerging systems and technologies for real-world examples. From introducing exergy and thermodynamic fundamentals to presenting the use of exergy methods for heating, refrigeration, and air conditioning systems, this book equips any researcher or practicing engineer with the tools needed to learn and master the application of exergy...

  11. Sustainability Challenges from Climate Change and Air Conditioning Use in Urban Areas

    Directory of Open Access Journals (Sweden)

    Karin Lundgren

    2013-07-01

    Full Text Available Global climate change increases heat loads in urban areas causing health and productivity risks for millions of people. Inhabitants in tropical and subtropical urban areas are at especial risk due to high population density, already high temperatures, and temperature increases due to climate change. Air conditioning is growing rapidly, especially in South and South-East Asia due to income growth and the need to protect from high heat exposures. Studies have linked increased total hourly electricity use to outdoor temperatures and humidity; modeled future predictions when facing additional heat due to climate change, related air conditioning with increased street level heat and estimated future air conditioning use in major urban areas. However, global and localized studies linking climate variables with air conditioning alone are lacking. More research and detailed data is needed looking at the effects of increasing air conditioning use, electricity consumption, climate change and interactions with the urban heat island effect. Climate change mitigation, for example using renewable energy sources, particularly photovoltaic electricity generation, to power air conditioning, and other sustainable methods to reduce heat exposure are needed to make future urban areas more climate resilient.

  12. Contribution of air conditioning adoption to future energy use under global warming

    Science.gov (United States)

    Davis, Lucas W.; Gertler, Paul J.

    2015-01-01

    As household incomes rise around the world and global temperatures go up, the use of air conditioning is poised to increase dramatically. Air conditioning growth is expected to be particularly strong in middle-income countries, but direct empirical evidence is scarce. In this paper we use high-quality microdata from Mexico to describe the relationship between temperature, income, and air conditioning. We describe both how electricity consumption increases with temperature given current levels of air conditioning, and how climate and income drive air conditioning adoption decisions. We then combine these estimates with predicted end-of-century temperature changes to forecast future energy consumption. Under conservative assumptions about household income, our model predicts near-universal saturation of air conditioning in all warm areas within just a few decades. Temperature increases contribute to this surge in adoption, but income growth by itself explains most of the increase. What this will mean for electricity consumption and carbon dioxide emissions depends on the pace of technological change. Continued advances in energy efficiency or the development of new cooling technologies could reduce the energy consumption impacts. Similarly, growth in low-carbon electricity generation could mitigate the increases in carbon dioxide emissions. However, the paper illustrates the enormous potential impacts in this sector, highlighting the importance of future research on adaptation and underscoring the urgent need for global action on climate change. PMID:25918391

  13. Contribution of air conditioning adoption to future energy use under global warming.

    Science.gov (United States)

    Davis, Lucas W; Gertler, Paul J

    2015-05-12

    As household incomes rise around the world and global temperatures go up, the use of air conditioning is poised to increase dramatically. Air conditioning growth is expected to be particularly strong in middle-income countries, but direct empirical evidence is scarce. In this paper we use high-quality microdata from Mexico to describe the relationship between temperature, income, and air conditioning. We describe both how electricity consumption increases with temperature given current levels of air conditioning, and how climate and income drive air conditioning adoption decisions. We then combine these estimates with predicted end-of-century temperature changes to forecast future energy consumption. Under conservative assumptions about household income, our model predicts near-universal saturation of air conditioning in all warm areas within just a few decades. Temperature increases contribute to this surge in adoption, but income growth by itself explains most of the increase. What this will mean for electricity consumption and carbon dioxide emissions depends on the pace of technological change. Continued advances in energy efficiency or the development of new cooling technologies could reduce the energy consumption impacts. Similarly, growth in low-carbon electricity generation could mitigate the increases in carbon dioxide emissions. However, the paper illustrates the enormous potential impacts in this sector, highlighting the importance of future research on adaptation and underscoring the urgent need for global action on climate change.

  14. Interference by new-generation mobile phones on critical care medical equipment

    NARCIS (Netherlands)

    van Lieshout, Erik Jan; van der Veer, Sabine N.; Hensbroek, Reinout; Korevaar, Johanna C.; Vroom, Margreeth B.; Schultz, Marcus J.

    2007-01-01

    INTRODUCTION: The aim of the study was to assess and classify incidents of electromagnetic interference (EMI) by second-generation and third-generation mobile phones on critical care medical equipment. METHODS: EMI was assessed with two General Packet Radio Service (GPRS) signals (900 MHz, 2 W, two

  15. Experimental benchmark and code validation for airfoils equipped with passive vortex generators

    DEFF Research Database (Denmark)

    Baldacchino, D.; Manolesos, M.; Ferreira, Célia Maria Dias

    2016-01-01

    Experimental results and complimentary computations for airfoils with vortex generators are compared in this paper, as part of an effort within the AVATAR project to develop tools for wind turbine blade control devices. Measurements from two airfoils equipped with passive vortex generators, a 30...

  16. Condition based monitoring, diagnosis and maintenance on operating equipments of a hydraulic generator unit

    International Nuclear Information System (INIS)

    Liu, X T; Feng, F Z; Si, A W

    2012-01-01

    According to performance characteristics of operating equipments in a hydraulic generator unit (HGU), the relative techniques on condition monitoring and fault diagnosis (CMFD) are introduced in this paper, especially the key technologies are emphasized, such as equipment monitoring, expert system (ES), intelligent diagnosis and condition based maintenance (CBM). Meanwhile, according to the instructor on CBM proposed by State electric power corporation, based on integrated mode, the main steps on implementation of CBM are discussed in this paper.

  17. IEEE standard for qualifying class IE equipment for nuclear power generating stations

    International Nuclear Information System (INIS)

    Anon.

    1974-01-01

    The Institute of Electrical and Electrical Engineers, Inc. (IEEE) standards for electrical equipment (Class IE) for nuclear power generating stations are given. The standards are to provide guidance for demonstrating and documenting the adequacy of electric equipment used in all Class IE and interface systems. Representative in containment design basis event conditions for the principal reactor types are included in the appendixes for guidance in enviromental simulation

  18. IEEE recommended practices for seismic qualification of Class 1E equipment for nuclear power generating stations

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    The IEEE has developed this document to provide direction for developing programs to seismically qualify Class 1E equipment for nuclear power generating stations. It supplements IEEE Std 323-1974, IEEE Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations, which describes the basic requirements for equipment qualification. The Class 1E equipment to be qualified by produres or standards established by this document are of many forms, characteristics, and materials; therefore, the document presents many acceptable methods with the intent of permitting the user to make a judicious selection from among the various options. In making such a selection, the user should choose those that best meet a particular equipment's requirements. Further, in using this document as a specification for the purchase of equipment, the many options should also be recognized and the document invoked accordingly. It is recommended that the need for specific standards for the seismic qualifiction of particular kinds of equipment be evaluated by those responsible for such documents and that consideration be given to the application of particular methods from these documents which are most suitable

  19. IEEE standard for design qualification of safety systems equipment used in nuclear power generating stations

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    This standard is written to serve as a general standard for qualification of all types of safety systems equipment, mechanical and instrumentation as well as electrical. It also establishes principles and procedures to be followed in preparing specific safety systems equipment standards. Guidance for qualifying specific safety systems equipment may be found in various specific equipment qualification standards that are now available or are being prepared. It is required that safety systems equipment in nuclear power generating stations meet or exceed its performance requirements throughout its installed life. This is accomplished by a disciplined program of design qualification and quality assurance of design, production, installation, maintenance and surveillance. This standard is for the design qualification section of the program only. Design qualification is intended to demonstrate the capability of the equipment design to perform its safety function(s) over the expected range of normal, abnormal, design basis event, post design basis event, and in-service test conditions. Inherent to design qualification is the requirement for demonstration, within limitations afforded by established technical state-of-the-art, that in-service aging throughout the qualified life established for the equipment will not degrade safety systems equipment from its original design condition to the point where it cannot perform its required safety function(s), upon demand. The above requirement reflects the primary role of design qualification to provide reasonable assurance that design- and age-related common failure modes will not occur during performance of safety function(s) under postulated service conditions

  20. Mountain Plains Learning Experience Guide: Heating, Refrigeration, & Air Conditioning.

    Science.gov (United States)

    Carey, John

    This Heating, Refrigeration, and Air Conditioning course is comprised of eleven individualized units: (1) Refrigeration Tools, Materials, and Refrigerant; (2) Basic Heating and Air Conditioning; (3) Sealed System Repairs; (4) Basic Refrigeration Systems; (5) Compression Systems and Compressors; (6) Refrigeration Controls; (7) Electric Circuit…

  1. Thermal Environment for Classrooms. Central System Approach to Air Conditioning.

    Science.gov (United States)

    Triechler, Walter W.

    This speech compares the air conditioning requirements of high-rise office buildings with those of large centralized school complexes. A description of one particular air conditioning system provides information about the system's arrangement, functions, performance efficiency, and cost effectiveness. (MLF)

  2. A model for estimation of potential generation of waste electrical and electronic equipment in Brazil

    International Nuclear Information System (INIS)

    Araújo, Marcelo Guimarães; Magrini, Alessandra; Mahler, Cláudio Fernando; Bilitewski, Bernd

    2012-01-01

    Highlights: ► Literature of WEEE generation in developing countries is reviewed. ► We analyse existing estimates of WEEE generation for Brazil. ► We present a model for WEEE generation estimate. ► WEEE generation of 3.77 kg/capita year for 2008 is estimated. ► Use of constant lifetime should be avoided for non-mature market products. - Abstract: Sales of electrical and electronic equipment are increasing dramatically in developing countries. Usually, there are no reliable data about quantities of the waste generated. A new law for solid waste management was enacted in Brazil in 2010, and the infrastructure to treat this waste must be planned, considering the volumes of the different types of electrical and electronic equipment generated. This paper reviews the literature regarding estimation of waste electrical and electronic equipment (WEEE), focusing on developing countries, particularly in Latin America. It briefly describes the current WEEE system in Brazil and presents an updated estimate of generation of WEEE. Considering the limited available data in Brazil, a model for WEEE generation estimation is proposed in which different methods are used for mature and non-mature market products. The results showed that the most important variable is the equipment lifetime, which requires a thorough understanding of consumer behavior to estimate. Since Brazil is a rapidly expanding market, the “boom” in waste generation is still to come. In the near future, better data will provide more reliable estimation of waste generation and a clearer interpretation of the lifetime variable throughout the years.

  3. Solar air conditioning. Dresden colloquium; Solare Klimatisierung. Dresdner Kolloquium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    Subjects: R + D activities in solar air conditioning; dessicative and evaporative cooling (DEC) - systems and components; Chances of solar air conditioning in Europe; Practical experience with solar-assisted air conditioning; Performance of a solar system at Lissabon; DEC system in the Alsenblock building, Berlin; Does solar air conditioning require specially designed buildings; Performance of solar heated adsorption refrigerators; Low-capacity absacity absorption systems for solar air conditioning. [German] Die Kolloquiumsschrift beinhaltet Unterlagen ueber die abgehandelten Themen. Sie lauten: F and E-Aktivitaeten im Bereich Solare Klimatisierung; SGK(DEC-Technik) - ausgefuehrte Anlagen und deren Komponenten; Chancen der solaren Klimatisierung in Europa; Erfahrungen mit der solarunterstuetzten Klimatisierung; Energieverbrauch und Regelung von SGK-Anlagen; Betriebserfahrungen einer Solaranlage in Lissabon; Realisierung der SGK im Alsenblock Berlin; Erfordert die solare Klimatisierung besondere Gebaeude?; Betriebserfahrungen mit solar beheizten Adsorptionskaeltemaschinen; Absorptionsanlagen kleiner Leistung fuer solare Klimatisierung. (orig.)

  4. Japanese and American competition in the development of scroll compressors and its impact on the American air conditioning industry

    Energy Technology Data Exchange (ETDEWEB)

    Ushimaru, Kenji (Energy International, Inc., Bellevue, WA (USA))

    1990-02-01

    This report examines the technological development of scroll compressors and its impact on the air conditioning equipment industry. Scroll compressors, although considered to be the compressors of the future for energy-efficient residential heat pumps and possibly for many other applications, are difficult to manufacture on a volume-production base. The manufacturing process requires computer-aided, numerically controlled tools for high-precision fabrication of major parts. Japan implemented a global strategy for dominating the technological world market in the 1970s, and scroll compressor technology benefited from the advent of new-generation machine tools. As a result, if American manufacturers of scroll compressors purchase or are essentially forced to purchase numerically controlled tools from Japan in the future, they will then become dependent on their own competitors because the same Japanese conglomerates that make numerically controlled tools also make scroll compressors. This study illustrates the importance of the basic machine tool industry to the health of the US economy. Without a strong machine tool industry, it is difficult for American manufacturers to put innovations, whether patented or not, into production. As we experience transformation in the air conditioning and refrigeration market, it will be critical to establish a consistent national policy to provide healthy competition among producers, to promote innovation within the industry, to enhance assimilation of new technology, and to eliminate practices that are incompatible with these goals. 72 refs., 8 figs., 1 tab.

  5. Intelligent energy management control of vehicle air conditioning system coupled with engine

    International Nuclear Information System (INIS)

    Khayyam, Hamid; Abawajy, Jemal; Jazar, Reza N.

    2012-01-01

    Vehicle Air Conditioning (AC) systems consist of an engine powered compressor activated by an electrical clutch. The AC system imposes an extra load to the vehicle's engine increasing the vehicle fuel consumption and emissions. Energy management control of the vehicle air conditioning is a nonlinear dynamic system, influenced by uncertain disturbances. In addition, the vehicle energy management control system interacts with different complex systems, such as engine, air conditioning system, environment, and driver, to deliver fuel consumption improvements. In this paper, we describe the energy management control of vehicle AC system coupled with vehicle engine through an intelligent control design. The Intelligent Energy Management Control (IEMC) system presented in this paper includes an intelligent algorithm which uses five exterior units and three integrated fuzzy controllers to produce desirable internal temperature and air quality, improved fuel consumption, low emission, and smooth driving. The three fuzzy controllers include: (i) a fuzzy cruise controller to adapt vehicle cruise speed via prediction of the road ahead using a Look-Ahead system, (ii) a fuzzy air conditioning controller to produce desirable temperature and air quality inside vehicle cabin room via a road information system, and (iii) a fuzzy engine controller to generate the required engine torque to move the vehicle smoothly on the road. We optimised the integrated operation of the air conditioning and the engine under various driving patterns and performed three simulations. Results show that the proposed IEMC system developed based on Fuzzy Air Conditioning Controller with Look-Ahead (FAC-LA) method is a more efficient controller for vehicle air conditioning system than the previously developed Coordinated Energy Management Systems (CEMS). - Highlights: ► AC interacts: vehicle, environment, driver components, and the interrelationships between them. ► Intelligent AC algorithm which uses

  6. Study on the Selection of Equipment Suppliers for Wind Power Generation EPC Project

    Science.gov (United States)

    Yang, Yuanyue; Li, Huimin

    2017-12-01

    In the EPC project, the purchase cost of equipments accounted for about 60% of the total project cost, thus, the selection of equipment suppliers has an important influence on the EPC project. This paper, took EPC project for the phase I engineering of Guizhou Huaxi Yunding wind power plant as research background, constructed the evaluation index system for the selection of equipment suppliers for wind power generation EPC project from multiple perspectives, and introduced matter-element extension evaluation model to evaluate the selection of equipment suppliers for this project from the qualitative and quantitative point of view. The result is consistent with the actual situation, which verifies the validity and operability of this method.

  7. Air-conditioning and ventilation systems and components of nuclear facilities

    International Nuclear Information System (INIS)

    2006-01-01

    The Guide defines the requirements for the design, implementation and operation of the air-conditioning and ventilation systems of nuclear facilities belonging to safety classes 3 and 4, and for the related documents to be submitted to STUK (Radiation and Nuclear Safety Authority, Finland). Furthermore, the Guide describes the inspections of air-conditioning and ventilation systems to be conducted by STUK during construction and operation of the facilities. As far as systems and components belonging to safety class 2 are concerned, STUK sets additional requirements case by case. In general, air-conditioning systems refer to systems designed to manage the indoor air cleanness, temperature, humidity and movement. In some rooms of a nuclear power plant, ventilation systems are also used to prevent radioactive materials from spreading outside the rooms. Guide YVL1.0 defines the safety principles concerning the air-conditioning and ventilation of nuclear power plants. Guide YVL2.0 gives the requirements for the design of nuclear power plant systems. In addition, YVLGuide groups 3, 4, 5 and 7 deal with the requirements for air-conditioning and ventilation systems with regard to the mechanical equipment, fire prevention, electrical systems, instrumentation and control technology, and the restriction of releases. The rules and regulations issued by the Ministry of the Environment and the Ministry of the Interior (RakMK, the Finnish building code) concerning the design and operation of air-conditioning and ventilation systems and the related fire protection design bases also apply to nuclear facilities. Exhaust gas treatment systems, condenser vacuum systems of boiling water reactor plants and leak collection systems are excluded from the scope of this Guide

  8. Effects of suspension of air-conditioning on airtight-type racks.

    Science.gov (United States)

    Kanzaki, M; Fujieda, M; Furukawa, T

    2001-10-01

    Although isolation racks are superior to open-type racks in terms of securing breeding conditions for laboratory animals, the contingency-proofing capability of the former has yet to be determined. Therefore, from the view of risk management, we studied the environmental change in isolation racks by forcibly suspending ventilation and air-conditioning and confirming the maximal time length for complete recovery to the original condition after restarting their operations. The isolation racks were placed in a room that was equipped with an independent air-conditioning system. When the inside condition of the racks reached 22-24 degrees C and 59-64% of relative humidity, the air-conditioning and ventilation were forcibly suspended and the subsequent temperature, relative humidity, ammonium and CO2 concentrations in the racks were measured over time. We found that after suspending the air-conditioning and ventilation, it took 40-60 min for temperature, and about 10 min for relative humidity to exceed the maximum values (temperature and relative humidity) referred to in the Showa 58 Nenban Guideline Jikken Doubutsu Shisetsu no Kenchiku oyobi Setsubi (Guidelines of buildings and facilities for experimental animals in Japan; Year 1983 edition). After 17 hr 25 min of the suspension of air-conditioning and ventilation, two rats were found dead. Then, the air-conditioning and ventilation were restarted. It took about 2 hr for temperature, and 50 min for relative humidity to regain the guideline values. The ammonium concentration stayed within the guideline value with a maximum concentration of 2 ppm in the experimental period, whereas the CO2 concentration was found to exceed 9% at the time of animal death.

  9. Decoupling dehumidification and cooling for energy saving and desirable space air conditions in hot and humid Hong Kong

    International Nuclear Information System (INIS)

    Lee, W.L.; Chen Hua; Leung, Y.C.; Zhang, Y.

    2012-01-01

    Highlights: ► The combined use of dedicated ventilation and dry cooling (DCDV) system was investigated. ► Investigations were based actual equipment performance data and realistic building and system characteristics. ► DCDV system could save 54% of the annual energy use for air-conditioning. ► DCDV system could better achieve the desired space air conditions. ► DCDV system could decouple dehumidification and cooling. - Abstract: The combined use of dedicated outdoor air ventilation (DV) and dry cooling (DC) air-conditioning system to decouple sensible and latent cooling for desirable space air conditions, better indoor air quality, and energy efficiency is proposed for hot and humid climates like Hong Kong. In this study, the performance and energy saving potential of DCDV system in comparison to conventional systems (constant air volume (CAV) system with and without reheat) for air conditioning of a typical office building in Hong Kong are evaluated. Through hour-by-hour simulations, using actual equipment performance data and realistic building and system characteristics, the cooling load profile, resultant indoor air conditions, condensation at the DC coil, and energy consumptions are calculated and analyzed. The results indicate that with the use of DCDV system, the desirable indoor conditions could be achieved and the annual energy use could be reduced by 54% over CAV system with reheat. The condensate-free characteristic at the DC coil to reduce risk of catching disease could also be realized.

  10. Visual inspection equipment for the secondary side of steam generators. Final report

    International Nuclear Information System (INIS)

    Hinton, M.S.; Chagnon, C.W.

    1981-05-01

    The development of miniature visual examination equipment capable of inspecting regions inside the tube bundles of nuclear steam generators to determine such factors as gap condition, tube outside surface condition, and material buildup is described. Tube-to-support plate interface regions at the tenth-support plate level in a once-through steam generator (Oconee 1) were visually examined. Other areas in the peripheral region were examined for conditions associated with available eddy-current and profilometer data

  11. Users manual. Pursuit program of use licenses of radioactive material or generator equipment of ionizing radiations

    International Nuclear Information System (INIS)

    Becerril M, V.M.; Villarreal, J.E.

    1992-05-01

    The objective of the program 'Databases for the pursuit of licenses of use of radioactive material', it consists on the application of a computer system carried out in dbase IV that it allows the control of the all the information related with those licenses for use, possession and storage of radioactive material or generator equipment of ionizing radiations. (Author)

  12. Installation of PMV Operation Program in DDC Controller and Air Conditioning Control Using PMV Directly as Set Point

    Science.gov (United States)

    Haramoto, Ken-Ichi

    In general, air conditioning control in a building is operated mainly by indoor air temperature control. Although the operators of the machine in the building accepted a claim for indoor air temperature presented by the building inhabitants, the indoor conditions have been often too cool or warm. Therefore, in an attempt to create better thermal environments, the author paid attention to the PMV that is a thermal comfort index. And then, the possibility of air conditioning control using the PMV directly as the set point was verified by employing actual equipment in an air conditioning testing room and an office building. Prior to the execution of this control, the operation program of the PMV was installed in a DDC controller for the air conditioning control. And information from indoor sensors and so on was inputted to the controller, and the computed PMV was used as the feedback variable.

  13. Utilization of Solar Energy for Air Conditioning System

    Directory of Open Access Journals (Sweden)

    Sutikno Juwari Purwo

    2018-01-01

    Full Text Available The purposes of this research are to do a system simulation of air conditioning utilizing solar energy with single effect absorption refrigeration method, analyze the coefficient of performance (COP for each absorbent-refrigerant variable and compare the effectivity of every absorbent-refrigerant variable used. COP is a constant that denotes the effeciency of a refrigeration system, that is ratio of work or useful output to the amount of work or energy input. The higher the number of COP, the more efficient the system is. Absorbent-refrigerant (working fluids variables used in this research depend on its chemical and thermodynamics properties. Steps in this research are including data collection and tabulation from literature and do a simulation of air conditioning system both commercial air conditioning system (using electrical energy and solar energy air conditioning system with Aspen Plus software. Next, run the simulation for each working fluid variables used and calculate the COP for each variable. Subsequently, analyze and compare the effectivity of all variables used from COP value and economical point of view with commercial air conditioning system. From the result of the simulation, can be concluded that solar air conditioning can achieve 98,85 % of energy savings than commercial air conditioning. Furthermore, from the calculation of COP, the highest COP value is achieved by solar conditioning system with LiNO3-NH3 as working fluid where 55% of the composition is the refrigerant and 45% of absorbent.

  14. Composite electric generator equipped with steam generator for heating reactor coolant

    International Nuclear Information System (INIS)

    Watabe, Masaharu; Soman, Yoshindo; Kawanishi, Kohei; Ota, Masato.

    1997-01-01

    The present invention concerns a composite electric generator having coolants, as a heating source, of a PWR type reactor or a thermonuclear reactor. An electric generator driving gas turbine is disposed, and a superheater using a high temperature exhaust gas of the gas turbine as a heating source is disposed, and main steams are superheated by the superheater to elevate the temperature at the inlet of the turbine. This can increase the electric generation capacity as well as increase the electric generation efficiency. In addition, since the humidity in the vicinity of the exit of the steam turbine is reduced, occurrence of loss and erosion can be suppressed. When cooling water of the thermonuclear reactor is used, the electric power generated by the electric generator driven by the gas turbine can be used upon start of the thermonuclear reactor, and it is not necessary to dispose a large scaled special power source in the vicinity, which is efficient. (N.H.)

  15. Thermal design of a modern, air-conditioned, single-floor, solar-powered desert house

    KAUST Repository

    Serag-Eldin, M. A.

    2011-01-01

    The paper presents a thermal analysis of a single-floor, solar-powered desert house. The house is air-conditioned and provides all modern comforts and facilities. Electrical power, which drives the entire energy system, is generated by roof

  16. An assessment the severe accident equipment survivability for the Korean Next Generation Reactor

    International Nuclear Information System (INIS)

    Lee, B. C.; Moon, Y. T.; Park, J. W.; Kho, H. J.; Lee, S. W.

    1999-01-01

    One of the prominent design approaches to cope with the severe accident challenges in the Korean Next Generation Reactor is an assessment of equipment survivability in the severe accident environment at early design stage. In compliance with 10CFR50.34(f) and SECY-93-087, this work addresses that a reasonable level of assurance be provided to demonstrate that sufficient instrumentation and equipment will survive the consequences of a severe accident and will be available so that the operator may recover from and trend severe core damage sequences, including those scenarios which result in 100 percent oxidation of the active fuel cladding. An analytical and systematic approach was used to identify the equipment and instrumentation of safety-function and define severe accident environments including temperature, pressure, humidity, and radiation before and after the reactor vessel breach. As a result, it was concluded that with minor exceptions, existing design basis equipment qualification methods are sufficient to provide a reasonable level of assurance that this equipment will function during a severe accident. Furthermore, supplemental severe accident equipment and instrument procurement requirements were identified. (author)

  17. Performance evaluation of an integrated automotive air conditioning and heat pump system

    International Nuclear Information System (INIS)

    Hosoz, M.; Direk, M.

    2006-01-01

    This study deals with the performance characteristics of an R134a automotive air conditioning system capable of operating as an air-to-air heat pump using ambient air as a heat source. For this aim, an experimental analysis has been performed on a plant made up of original components from an automobile air conditioning system and some extra equipment employed to operate the system in the reverse direction. The system has been tested in the air conditioning and heat pump modes by varying the compressor speed and air temperatures at the inlets of the indoor and outdoor coils. Evaluation of the data gathered in steady state test runs has shown the effects of the operating conditions on the capacity, coefficient of performance, compressor discharge temperature and the rate of exergy destroyed by each component of the system for both operation modes. It has been observed that the heat pump operation provides adequate heating only in mild weather conditions, and the heating capacity drops sharply with decreasing outdoor temperature. However, compared with the air conditioning operation, the heat pump operation usually yields a higher coefficient of performance and a lower rate of exergy destruction per unit capacity. It is also possible to improve the heating mode performance of the system by redesigning the indoor coil, using another refrigerant with a higher heat rejection rate in the condenser and employing a better heat source such as the engine coolant or exhaust gases

  18. Comparative economic assessment of the energy performance of air-conditioning within the Mexican residential sector

    Directory of Open Access Journals (Sweden)

    Ivan Oropeza-Perez

    2016-11-01

    Full Text Available This work shows a sensitivity analysis of the economic impact of different energy performances of air-conditioning within the Mexican housing sector. For this purpose, a cooling-load calculator program in function of the indoor temperature is developed. The program also calculates the electricity consumption along with the expenditure with the different residential rates of the Mexican Federal Commission of Electricity (CFE, initials in Spanish set according to the season of the year and zone of the country. After the results onto the national-scale scenario are validated with the literature, a sensitivity analysis is carried out by changing three parameters that are considered as influential on the consumption and which can be considered as energy saving strategies. With these strategies, it is found that the indoor temperature decrease due to the use of a passive cooling system is the most important characteristic to take into account followed by the coefficient of performance (COP of the air-conditioning and the increase of the comfort temperature set-point, respectively. Thereby, an economic analysis is carried out, finding an annual saving up to 770 USD within a single air-conditioned dwelling having a payback period of 3 years for using a combination of passive cooling techniques and increasing the comfort temperature set-point; or a 2 years payback period if the air-conditioning is changed by a high-efficient equipment.

  19. Geothermal as a heat sink application for raising air conditioning efficency

    Science.gov (United States)

    Ibrahim, Hesham Safwat Osman Mohamed

    2016-04-01

    Objective: Geothermal applications in heating, ventilation, air-conditioning is a US technology for more than 30 years old ,which saves more than 30% average energy cost than the traditional air-conditioning systems systems. Applying this technology in Middle East and African countries would be very feasible specially in Egypt specially as it suffers Electric crisis --The temperature of the condensers and the heat rejecting equipment is much higher than the Egyptian land at different depth which is a great advantages, and must be measured, recorded, and studied accurately -The Far goal of the proposal is to construct from soil analysis a temperature gradient map for Egypt and , African countries on different depth till 100 m which is still unclear nowadays and must be measured and recorded in databases through researches - The main model of the research is to study the heat transfer gradient through the ground earth borehole,grout,high density polyethylene pipes , and water inlet temperature which affect the electric efficiency of the ground source heat pump air conditioning unit Impact on the Region: Such research result will contribute widely in Energy saving sector specially the air conditioning sector in Egypt and the African countries which consumes more than 30% of the electric consumption of the total consumption . and encouraging Green systems such Geothermal to be applied

  20. PROSPECTS FOR THE DEVELOPMENT OF TECHNOLOGY AIR CONDITIONING

    Directory of Open Access Journals (Sweden)

    O. V. Chernyshova

    2008-03-01

    Full Text Available In the article the evaporation cooling and spray (aqueous and air-to-water types of the air-conditioning systems are considered, their merits and demerits are analyzed; the new scheme of a conditioner is offered.

  1. Application of solar energy to air conditioning systems

    Science.gov (United States)

    Nash, J. M.; Harstad, A. J.

    1976-01-01

    The results of a survey of solar energy system applications of air conditioning are summarized. Techniques discussed are both solar powered (absorption cycle and the heat engine/Rankine cycle) and solar related (heat pump). Brief descriptions of the physical implications of various air conditioning techniques, discussions of status, proposed technological improvements, methods of utilization and simulation models are presented, along with an extensive bibliography of related literature.

  2. Uncertainty Evaluation of Residential Central Air-conditioning Test System

    Science.gov (United States)

    Li, Haoxue

    2018-04-01

    According to national standards, property tests of air-conditioning are required. However, test results could be influenced by the precision of apparatus or measure errors. Therefore, uncertainty evaluation of property tests should be conducted. In this paper, the uncertainties are calculated on the property tests of Xinfei13.6 kW residential central air-conditioning. The evaluation result shows that the property tests are credible.

  3. Computer Model to Estimate Reliability Engineering for Air Conditioning Systems

    International Nuclear Information System (INIS)

    Afrah Al-Bossly, A.; El-Berry, A.; El-Berry, A.

    2012-01-01

    Reliability engineering is used to predict the performance and optimize design and maintenance of air conditioning systems. Air conditioning systems are expose to a number of failures. The failures of an air conditioner such as turn on, loss of air conditioner cooling capacity, reduced air conditioning output temperatures, loss of cool air supply and loss of air flow entirely can be due to a variety of problems with one or more components of an air conditioner or air conditioning system. Forecasting for system failure rates are very important for maintenance. This paper focused on the reliability of the air conditioning systems. Statistical distributions that were commonly applied in reliability settings: the standard (2 parameter) Weibull and Gamma distributions. After distributions parameters had been estimated, reliability estimations and predictions were used for evaluations. To evaluate good operating condition in a building, the reliability of the air conditioning system that supplies conditioned air to the several The company's departments. This air conditioning system is divided into two, namely the main chilled water system and the ten air handling systems that serves the ten departments. In a chilled-water system the air conditioner cools water down to 40-45 degree F (4-7 degree C). The chilled water is distributed throughout the building in a piping system and connected to air condition cooling units wherever needed. Data analysis has been done with support a computer aided reliability software, this is due to the Weibull and Gamma distributions indicated that the reliability for the systems equal to 86.012% and 77.7% respectively. A comparison between the two important families of distribution functions, namely, the Weibull and Gamma families was studied. It was found that Weibull method performed for decision making.

  4. 2013 German refrigeration and air conditioning meeting. Proceedings

    International Nuclear Information System (INIS)

    2013-01-01

    These proceedings cover the following main topics: cryoengineering - superconduction / energy storage; cryoapplications in biology and medicine; metrology; adsorption processes; condensation/evaporation; working fluids / simulation; ice production; plants and compressors; expansion and ejectors or recooling; use of cooling (passenger car air conditioning, supermarket); refrigerants; plant efficiency; emissions and legislation; air conditioning and use of heat pumps; air quality and control; building technology and block-type thermal power stations. [de

  5. 2014 German refrigeration and air conditioning meeting. Proceedings

    International Nuclear Information System (INIS)

    2014-01-01

    The proceedings of the 2014 German refrigeration and air conditioning meeting contain contributions on the following topics: cryotechnology, fundamentals and materials for the refrigeration and heat pump technology, devices and components for the refrigeration and heat pump technology, applications of refrigeration technologies, air conditioning technology and heat pump applications, cryotechnology in biology and medicine, heat transfer and ventilation, guidelines and legal topics, refrigerant fluid - oil mixtures, control and surveillance, simulation and control, ambient air.

  6. The microbiological quality of air improves when using air conditioning systems in cars.

    Science.gov (United States)

    Vonberg, Ralf-Peter; Gastmeier, Petra; Kenneweg, Björn; Holdack-Janssen, Hinrich; Sohr, Dorit; Chaberny, Iris F

    2010-06-01

    Because of better comfort, air conditioning systems are a common feature in automobiles these days. However, its impact on the number of particles and microorganisms inside the vehicle--and by this its impact on the risk of an allergic reaction--is yet unknown. Over a time period of 30 months, the quality of air was investigated in three different types of cars (VW Passat, VW Polo FSI, Seat Alhambra) that were all equipped with a automatic air conditioning system. Operation modes using fresh air from outside the car as well as circulating air from inside the car were examined. The total number of microorganisms and the number of mold spores were measured by impaction in a high flow air sampler. Particles of 0.5 to 5.0 microm diameter were counted by a laser particle counter device. Overall 32 occasions of sampling were performed. The concentration of microorganisms outside the cars was always higher than it was inside the cars. Few minutes after starting the air conditioning system the total number of microorganisms was reduced by 81.7%, the number of mold spores was reduced by 83.3%, and the number of particles was reduced by 87.8%. There were no significant differences neither between the types of cars nor between the types of operation mode of the air conditioning system (fresh air vs. circulating air). All parameters that were looked for in this study improved during utilization of the car's air conditioning system. We believe that the risk of an allergic reaction will be reduced during use also. Nevertheless, we recommend regular maintenance of the system and replacement of older filters after defined changing intervals.

  7. Modeling and control of a variable-speed wind turbine equipped with permanent magnet synchronous generator

    Energy Technology Data Exchange (ETDEWEB)

    Aliprantis, D.C.; Papathanassiou, S.A.; Papadopoulos, M.P.; Kladas, A.G. [Purdue University, Electrical and Computer Engineering, West Lafayette, IN (United States)

    2000-08-01

    In this paper the operation of a variable-speed, stall regulated wind turbine equipped with a permanent magnet synchronous generator (PMSG) is examined. The emphasis is placed on the analysis of the electric part of the system, i.e. the electrical generator, the power electronics converters and the control. The operational characteristics of the machine are investigated through a series of computer simulations and the speed control system is designed to maximize the power output and achieve a smooth torque and power profile. (orig.)

  8. Effects of Wind Turbines Equipped with Doubly-fed Induction Generators on Distance Protection

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Nowadays wind energy is the fastest growing renewable energy resource in the world. The problems of integrating wind farms are caused by changes of wind speed during a day. Moreover, the behaviors of wind turbines equipped with doubly-fed induction generators differ fundamentally from synchronous generators. Therefore, more considerations are needed to analyze the performances of the distance protection relays. The protection of a wind farm with distance relay is inspected. By changing the conditions of the wind farm, the characteristics of the distance relay are studied.

  9. Articulated, Performance-Based Instruction Objectives Guide for Air Conditioning, Refrigeration, and Heating. Volume II (Second Year).

    Science.gov (United States)

    Henderson, William Edward, Jr., Ed.

    This articulation guide contains 17 units of instruction for the second year of a two-year vocational program designed to prepare the high school graduate to install, maintain, and repair various types of residential and commercial heating, air conditioning, and refrigeration equipment. The units are designed to help the student to expand and…

  10. FAULT TREE ANALYSIS FOR EXPOSURE TO REFRIGERANTS USED FOR AUTOMOTIVE AIR CONDITIONING IN THE U.S.

    Science.gov (United States)

    A fault tree analysis was used to estimate the number of refrigerant exposures of automotive service technicians and vehicle occupants in the United States. Exposures of service technicians can occur when service equipment or automotive air-conditioning systems leak during servic...

  11. The Future of Air Conditioning for Buildings - Executive Summary

    Energy Technology Data Exchange (ETDEWEB)

    Goetzler, William [Navigant Consulting Inc., Burlington, MA (United States); Guernsey, Matt [Navigant Consulting Inc., Burlington, MA (United States); Young, J. [Navigant Consulting Inc., Burlington, MA (United States); Fuhrman, J. [Navigant Consulting Inc., Burlington, MA (United States); Abdelaziz, Omar [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-07-01

    The Building Technologies Office (BTO), within the U.S. Department of Energy’s (DOE) Office of Energy Efficiency and Renewable Energy, works with researchers and industry to develop and deploy technologies that can substantially reduce energy consumption and greenhouse gas (GHG) emissions in residential and commercial buildings. Air conditioning (A/C) systems in buildings contribute to GHG emissions both directly through refrigerant emissions, as well as indirectly through fossil fuel combustion for power generation. BTO promotes pre-competitive research and development (R&D) on next-generation HVAC technologies that support the phase down of hydrofluorocarbon (HFC) production and consumption, as well as cost-effective energy efficiency improvements. Over the past several decades, product costs and lifecycle cooling costs have declined substantially in many global markets due to improved, higher-volume manufacturing and higher energy efficiency driven by R&D investments and efficiency policies including minimum efficiency standards and labeling programs.1 This report characterizes the current landscape and trends in the global A/C market, including discussion of both direct and indirect climate impacts, and potential global warming impacts from growing global A/C usage. The report also documents solutions that can help achieve international goals for energy efficiency and GHG emissions reductions. The solutions include pathways related to low-global warming potential2 (GWP) refrigerants, energy efficiency innovations, long-term R&D initiatives, and regulatory actions. DOE provides, with this report, a fact-based vision for the future of A/C use around the world. DOE intends for this vision to reflect a broad and balanced aggregation of perspectives. DOE brings together this content in an effort to support dialogue within the international community and help keep key facts and objectives at the forefront among the many important discussions.

  12. Experimental benchmark and code validation for airfoils equipped with passive vortex generators

    International Nuclear Information System (INIS)

    Baldacchino, D; Ferreira, C; Florentie, L; Timmer, N; Van Zuijlen, A; Manolesos, M; Chaviaropoulos, T; Diakakis, K; Papadakis, G; Voutsinas, S; González Salcedo, Á; Aparicio, M; García, N R.; Sørensen, N N.; Troldborg, N

    2016-01-01

    Experimental results and complimentary computations for airfoils with vortex generators are compared in this paper, as part of an effort within the AVATAR project to develop tools for wind turbine blade control devices. Measurements from two airfoils equipped with passive vortex generators, a 30% thick DU97W300 and an 18% thick NTUA T18 have been used for benchmarking several simulation tools. These tools span low-to-high complexity, ranging from engineering-level integral boundary layer tools to fully-resolved computational fluid dynamics codes. Results indicate that with appropriate calibration, engineering-type tools can capture the effects of vortex generators and outperform more complex tools. Fully resolved CFD comes at a much higher computational cost and does not necessarily capture the increased lift due to the VGs. However, in lieu of the limited experimental data available for calibration, high fidelity tools are still required for assessing the effect of vortex generators on airfoil performance. (paper)

  13. DISAIN SIMULATOR AUTOMOTIVE AIR CONDITIONING UNTUK MENINGKATKAN KOMPETENSI MAHASISWA

    Directory of Open Access Journals (Sweden)

    Kamin Sumardi

    2015-08-01

    Full Text Available Perkembangan teknologi automotive air conditioning dan aplikasinya sangat cepat, salah satunya dengan menerapkan green technology. Penerapan green technology pada teknologi air conditioning, karena masih menggunakan refrigeran yang mengandung unsur kimia yang merusak lapisan ozon dan pemanasan global. Alih teknologi bidang air conditioning yang ramah lingkungan, belum dibarengi dengan ketersediaan tenaga kerja pada tingkat SMK dan perguruan tinggi yang memadai, baik kuantitas maupun kompetensinya. Pada level SMK dan perguruan tinggi, kompetensi akademik dan vokasional bidang automotive air conditioning harus terus ditingkatkan dan diperbaharui sesuai dengan perkembangan teknologinya. Penelitian ini bertujuan untuk menghasilkan simulator automotive air conditioner dan model pembelajaran tata udara pada otomotif berwawasan teknologi ramah lingkungan. Penelitian menggunakan metode research and development dengan langkah-langkah: studi pendahuluan, perencanaan, pengembangan melalui uji coba simulator, validasi, dan produk akhir. Simulator dibuat sesuai dengan kondisi di dunia kerja agar tidak terjadi miskonsepsi dan mala-praktek automotive air conditioning. Simulator ini dibuat secara kompak dan mobile atau dapat dipindah dan dibawa. Model pembelajaran disesuaikan dengan kebutuhan kompetensi yang dipersyaratkan. Hasil penelitian menunjukkan bahwa dengan bantuan simulator automotive air conditioner dan model pembelajaran yang tepat mahasiswa mampu menyerap konsep dan praktek lebih cepat 85%. Hasil belajar pada ranah afektif, kognitif, psikomotor dan kompetensi meningkat secara signifikan.

  14. Thermal analysis of a direct evaporative cooling system enhancement with desiccant dehumidification for vehicular air conditioning

    International Nuclear Information System (INIS)

    Alahmer, Ali

    2016-01-01

    Highlights: • Thermal analysis was conducted to design a desiccant evaporative cooling system for vehicular air conditioning. • EC is more efficient than the conventional air conditioning when the gasoline price is more than 0.34 $/liter. • Drawbacks of evaporative cooler of increased weight and reduced COP. • A rotary desiccant dehumidifier with generation was combined with evaporative cooling to be more efficient. - Abstract: This manuscript analyzes the sub-systems of evaporative cooler (EC) combined with desiccant dehumidification and regeneration for automotive air conditioning purpose. The thermodynamic and psychometric analysis was conducted to design all evaporative cooling system components in terms of desiccant selection, regeneration process, compact heat exchanger and evaporative cooler. Moreover, the effect of the desiccant, heat exchanger and evaporative performances on the mass flow rate and water sprayed required for evaporative cooling system was investigated. The results show that the theoretical evaporative cooling design will achieve two main objectives: lower fuel consumption and less environmental pollutants. However, it has the two drawbacks in terms of increased weight and reduces the coefficient of performance (COP). The main remark is that evaporating cooling system is more efficient than the conventional air conditioning when the gasoline price is more than 0.34 $/liter.

  15. Monitoring and analysis of an absorption air-conditioning system

    Energy Technology Data Exchange (ETDEWEB)

    Perez de Vinaspre, M.; Bourouis, M.; Coronas, A. [Centro de Innovacion Tecnologica en Revalorizacion Energetica y Refrigeracion, Tarragona (Spain); Garcia, A.; Soto, V.; Pinazo, J.M. [E.T.S. Ingenieros Industriales, Valencia (Spain)

    2004-09-01

    In the last few years, high-energy consumption due to air-conditioning has led to a growing interest in the efficient use of energy in buildings. Although simulation programs have always been the main tools for analyzing energy in buildings, the reliability of their results is often compromised by a lack of certainty to reflect real conditions. The aim of this work is to monitorize and analyze the thermal behavior of an absorption-based air-conditioning installation of a university building in Tarragona, Spain. The existing monitoring system of the installation has been improved by implementing additional sensors and flow meters. The data has been stored during summer 2002 and used to assess the energy balance of the air-conditioning installation and the operational regime of the absorption chiller. [Author].

  16. A RADIANT AIR-CONDITIONING SYSTEM USING SOLAR-DRIVEN

    Directory of Open Access Journals (Sweden)

    S. A. ABDALLA

    2006-12-01

    Full Text Available Every air-conditioning system needs some fresh air to provide adequate ventilation air required to remove moisture, gases like ammonia and hydrogen sulphide, disease organisms, and heat from occupied spaces. However, natural ventilation is difficult to control because urban areas outside air is often polluted and cannot be supplied to inner spaces before being filtered. Besides the high electrical demand of refrigerant compression units used by most air-conditioning systems, and fans used to transport the cool air through the thermal distribution system draw a significant amount of electrical energy in comparison with electrical energy used by the building thermal conditioning systems. Part of this electricity heats the cooled air; thereby add to the internal thermal cooling peak load. In addition, refrigerant compression has both direct and indirect negative effects on the environment on both local and global scales. In seeking for innovative air-conditioning systems that maintain and improve indoor air quality under potentially more demanding performance criteria without increasing environmental impact, this paper presents radiant air-conditioning system which uses a solar-driven liquid desiccant evaporative cooler. The paper describes the proposed solar-driven liquid desiccant evaporative cooling system and the method used for investigating its performance in providing cold water for a radiant air-conditioning system in Khartoum (Central Sudan. The results of the investigation show that the system can operate in humid as well as dry climates and that employing such a system reduces air-conditioning peak electrical demands as compared to vapour compression systems.

  17. Generation of floor spectra compatible time histories for equipment seismic qualification in nuclear power plants

    International Nuclear Information System (INIS)

    Shyu, Y.-S.; Luh, Gary G.; Blum, Arie

    2004-01-01

    This paper proposes a procedure for generating floor response spectra compatible time histories used for equipment seismic qualification in nuclear power plants. From the 84th percentile power spectrum density function of an earthquake ensemble of four randomly generated time history motions, a statistically equivalent time history can be obtained by converting the power spectrum density function from the frequency domain into the time domain. With minor modification, if needed, the converted time history will satisfy both the spectral and the power spectrum density enveloping criteria, as required by the USNRC per Revision 2 of the Standard Review Plan, Section 3.7.1. Step-by-step generating procedures and two numerical examples are presented to illustrate the applications of the methodology. (author)

  18. Solar-Driven Air-Conditioning Cycles: A Review

    Directory of Open Access Journals (Sweden)

    A. M. Abu-Zour

    2007-12-01

    Full Text Available Most conventional cooling/refrigeration systems are driven by fossil fuel combustion, and therefore give rise to emission of environmentally damaging pollutants. In addition, many cooling systems employ refrigerants, which are also harmful to the environment in terms of their Global Warming Potential (GWP and Ozone Depletion Potential (ODP. Development of a passive or hybrid solar-driven air-conditioning system is therefore of interest as exploitation of such systems would reduce the demand for grid electricity particularly at times of peak load. This paper presents a review of various cooling cycles and summarises work carried out on solar-driven air-conditioning systems.

  19. Equipment for accident rel+ef of steam generator with balancino. tank

    International Nuclear Information System (INIS)

    Matal, O.; Martoch, J.

    1982-01-01

    The concept of equipment for relieving steam generators in case of accident consists in the introduction of a pipe into the balancing tank in such a manner that it passes through an inert atmosphere area and empties to the liquid metal area. On the pipe outside the balancing tank a pressure-burst membrane is placed in the usual way. At least one opening should be made on the accident relief pipe in the balancing tank below the level of the liquid metal, preferably immediately under the minimal liquid level. (B.S.)

  20. Retrofitting Inefficient Rooftop Air-Conditioning Units Reduces U.S. Navy Energy Use (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2014-04-01

    As part of the U.S. Navy's overall energy strategy, the National Renewable Energy Laboratory (NREL) partnered with the Naval Facilities Engineering Command (NAVFAC) to demonstrate market-ready energy efficiency measures, renewable energy generation, and energy systems integration. One such technology - retrofitting rooftop air-conditioning units with an advanced rooftop control system - was identified as a promising source for reducing energy use and costs, and can contribute to increasing energy security.

  1. IEEE Std 323-1983: IEEE standard for qualifying Class 1E equipment for nuclear power generating stations

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This standard describes the basic requirements for qualifying Class 1E equipment with interfaces that are to be used in nuclear power generating stations. The requirements presented include the principles, procedures, and methods of qualification. These qualification requirements, when met, will confirm the adequacy of the equipment design under normal, abnormal, design basis event, post design basis event, and in-service test conditions for the performance of safety function(s). The purpose of this standard is to identify requirements for the qualification of Class 1E equipment, including those interfaces whose failure could adversely affect the performance of Class 1E equipment and systems. The methods described shall be used for qualifying equipment, extending qualification, and updating qualification if the equipment is modified. Other issued IEEE standards which present qualification methods for specific equipment or components, or both, and those that deal with parts of the qualification program, may be used to supplement this standard, as applicable

  2. [Relationships between air conditioning, airborne microorganisms and health].

    Science.gov (United States)

    Parat, S; Perdrix, A; Baconnier, P

    1999-01-01

    Concurrently with the increase of air-conditioning, potentially severe or frequent new diseases have emerged, giving rise to social and economical consequences. The first part of this work is a state of the art review of the relationships between air-conditioning, airborne microorganisms and health, through a technical, metrological and medical approach. The second part presents four studies performed in this field. Two of them deal with the relationship between airborne microorganisms and technical features of air-conditioning. Measurements performed on actual sites demonstrated the benefit of using high efficiency filters and low risk components in air-conditioning systems. The third study was aimed to look for a relationship between airborne microorganisms and sick building syndrome symptoms. Statistical analyses of individual data revealed significant associations between airborne bacteria or fungi and symptoms. These results may be the first step in determining a dose-response relationship, in order to define threshold limit values in this field. In the fourth study, the contribution of particle counting in assessing exposure to airborne microorganisms was explored by monitoring simultaneous variations of microbial and particle concentrations. The results showed that associating particle counting may allow to detect microbial variations instantaneously, and therefore improve the assessment of exposure to airborne microorganisms.

  3. Design of energy efficient ventilation and air-conditioning systems

    CERN Document Server

    Seppänen, Olli; Bertilsson, Thore; Maripuu, Mari-Liis; Lamy, Hervé; Vanden Borre, Alex

    2012-01-01

    This guidebook covers numerous system components of ventilation and air-conditioning systems and shows how they can be improved by applying the latest technology products. Special attention is paid to details, which are often overlooked in the daily design practice, resulting in poor performance of high quality products once they are installed in the building system.

  4. Model development for air conditioning system in heavy duty trucks

    NARCIS (Netherlands)

    Kessels, J.T.B.A.; van den Bosch, P.P.J.; Zhang, Quansheng; Li, Shengbo Eben; Deng, Kun

    2016-01-01

    This chapter presents a modelling approach for the air conditioning (AC) system in heavy duty trucks. The presented model entails two major elements: a mechanical compressor model and a thermal AC model. The compressor model describes the massflow of the refrigerant as well as the mechanical power

  5. Step response and frequency response of an air conditioning system

    NARCIS (Netherlands)

    Crommelin, R.D.; Jackman, P.J.

    1978-01-01

    A system of induction units of an existing air conditioning system has been analyzed with respect to its dynamic properties. Time constants were calculated and measured by analogue models. Comparison with measurements at the installation itself showed a reasonable agreement. Frequency responses were

  6. 2016 German refrigeration and air conditioning meeting. Proceedings

    International Nuclear Information System (INIS)

    2016-01-01

    The following topics were dealt with: Large cryogenic facilities, relief valves, liquid helium, liquid-nitrogen and liquid hydrogen cooling, new concepts, foundations and materials of the heat-pump techniques, evaporation, phase-change materials, absorption, afterheat usage, ionic liquids, sorption, condensers, heat exchangers, back-cooling systems, refrigerants, caron dioxide, mobile applications, efficiency and optimization, air conditioning.

  7. Developed adaptive neuro-fuzzy algorithm to control air conditioning ...

    African Journals Online (AJOL)

    The paper developed artificial intelligence technique adaptive neuro-fuzzy controller for air conditioning systems at different pressures. The first order Sugeno fuzzy inference system was implemented and utilized for modeling and controller design. In addition, the estimation of the heat transfer rate and water mass flow rate ...

  8. Human requirements in future air-conditioned environments

    DEFF Research Database (Denmark)

    Fanger, Povl Ole

    1999-01-01

    Although air-conditioning has played a positive role for economic development in warm climates, its image is globally mixed. Field studies demonstrate that there are substantial numbers of dissatisfied people in many buildings, among them those suffering from Sick Building Syndrome (SBS) symptoms...

  9. Human requirements in future air-conditioned environments

    DEFF Research Database (Denmark)

    Fanger, Povl Ole

    2001-01-01

    Although air-conditioning has played a positive role for economic development in warm climates, its image is globally mixed. Field studies demonstrate that there are substantial numbers of dissatisfied people in many buildings, among them those suffering from Sick Building Syndrome (SBS) symptoms...

  10. Human requirements in future air-conditioned environments

    DEFF Research Database (Denmark)

    Fanger, Povl Ole

    2002-01-01

    Air-conditioning of buildings has played a very positive role for economic development in warm climates. Still its image is globally mixed. Field studies demonstrate that there are substantial numbers of dissatisfied people in many buildings, among them those suffering from SBS symptoms, even...

  11. The minimum work required for air conditioning process

    International Nuclear Information System (INIS)

    Alhazmy, Majed M.

    2006-01-01

    This paper presents a theoretical analysis based on the second law of thermodynamics to estimate the minimum work required for the air conditioning process. The air conditioning process for hot and humid climates involves reducing air temperature and humidity. In the present analysis the inlet state is the state of the environment which has also been chosen as the dead state. The final state is the human thermal comfort fixed at 20 o C dry bulb temperature and 60% relative humidity. The general air conditioning process is represented by an equivalent path consisting of an isothermal dehumidification followed by a sensible cooling. An exergy analysis is performed on each process separately. Dehumidification is analyzed as a separation process of an ideal mixture of air and water vapor. The variations of the minimum work required for the air conditioning process with the ambient conditions is estimated and the ratio of the work needed for dehumidification to the total work needed to perform the entire process is presented. The effect of small variations in the final conditions on the minimum required work is evaluated. Tolerating a warmer or more humid final condition can be an easy solution to reduce the energy consumptions during critical load periods

  12. The characteristics of welded joints for air conditioning application

    Science.gov (United States)

    Weglowski, M. St.; Weglowska, A.; Miara, D.; Kwiecinski, K.; Błacha, S.; Dworak, J.; Rykala, J.; Pikula, J.; Ziobro, G.; Szafron, A.; Zimierska-Nowak, P.; Richert, M.; Noga, P.

    2017-10-01

    In the paper the results of metallographic examination of welded joints for air-conditioning elements are presented. The European directives 2006/40/EC on the greenhouse gasses elimination demand to stop using traditional refrigerant and to change it to R744 (CO2) medium in air conditioning installation. The R744 refrigerant is environmental friendly medium if compared with standard solution such as R12, R134a or R1234yf and safer for passengers than R1234yf. The non-standard thermodynamic parameters of the R744 which translate into high pressure and high temperature require specific materials to develop the shape and to specify the technology of manufacturing for the particular elements of the conduits and moreover the technologies of joining for the whole structure, which would meet the exploitation requirements of the new air-conditioning system. To produce the test welded joints of stainless steels four different joining technologies were applied: laser welding, plasma welding, electron beam welding as well as high speed rotation welding. This paper describes the influence of the selected welding process on the macrostructure and microstructure of welded joints of AISI 304 and AISI 316L steels. The results indicated that plasma welding laser welding and electron beam welding technologies guaranty the proper quality of welded joints and can be used for the air conditioning application in automotive industry. However, high speed rotation welding not guarantee the good quality of welded joints and cannot be used for above application.

  13. Structural steels for power generating equipment and heat and chemical heat treatments

    International Nuclear Information System (INIS)

    Astaf'ev, A.A.

    1979-01-01

    Development of structural steels for power generating equipment and for reactor engineering, in particular, is elucidated. Noted is utilization of the 15Kh2NMFA steels for the WWER-1000 reactor vessels, the 10GN2MFA steels for steam generators, pressurizers, vessels of the automatic emergency shut down and safety system; the 00Kh12N3DL steel for cast pump vessels and main locking bars. The recommendations on heat treatment of big forgings, for instance, ensuring the necessary complex of mechanical properties are given. Diffusion chromizing with subsequent nitriding of austenitic steels which increase durability of the components in BN reactors more than 4 times, is practised on a large scale

  14. Development of microstructure to optimise mechanical performance of power generation equipment

    International Nuclear Information System (INIS)

    Marshall, P.

    1986-11-01

    The factors responsible for the development of microstructure in CEGB construction ceramics and steels is assessed as a function of composition, thermomechanical treatment, thermal ageing and environmental degradation. The relationships between microstructure and mechanical properties (tensile, toughness, creep and fatigue) of relevance to structures operating in power generation equipment is then developed in quantitative terms. The conclusions from the assessment are as follows: 1 The relationship between microstructure and mechanical properties of construction ceramics and steels used in the power generation industry has been assessed. 2 Factors which significantly influence microstructure and thus mechanical properties are chemical composition, thermomechanical treatment, ageing and environmental degradation. The influence of such microstructural changes in tensile, toughness, fatigue and creep properties of ceramics and steels is assessed. 3 The benefits arising from an understanding of materials behaviour are discussed in terms of improved materials and the assessment of plant performance. (author)

  15. Design principles and clinical possibilities with a new generation of radiation therapy equipment

    Energy Technology Data Exchange (ETDEWEB)

    Ruden, B P [Department of Hospital physics Karolinska institute, (Sudan)

    1997-12-31

    The main steps in the development of isocentric megavoltage external beam radiation therapy machines are briefly reviewed identifying three principal types or generations of equipment to date. The new fourth generation of equipment presented here is characterized by considerably increased flexibility in dose delivery through the use of scanned elementary electron and photon beams of very high quality. Furthermore, the wide energy range and the possibility of using high resolution multi leaf collimation with all beam modalities makes it possible to simplify irradiation techniques and increase the accuracy in dose delivery. The main design features are described including a dual magnet scanning system, a photon beam purging magnet, a helium atmosphere in the treatment head, a beam`s eye view video read-out system of the collimator setting and a radiotherapeutic computed tomography facility. Some of the clinical applications of this new type of radiation therapy machine are finally reviewed, such as the ease of performance, became flattening, beam filtering and compensation, and the simplification of many treatment techniques using the wide spectrum of high quality electron and photon beams. Finally, the interesting possibility of doing conformation and more general isocentric treatments with non-uniform beams using the multi leaf collimator and the scanning systems are demonstrated. 9 figs., 1 tab.

  16. The application of condensate water as an additional cooling media intermittently in condenser of a split air conditioning

    Science.gov (United States)

    Ardita, I. N.; Subagia, I. W. A.

    2018-01-01

    The condensate water produced by indoor a split air conditioning is usually not utilized and thrown away into the environment. The result of measurement shows that the temperature of condensate water produced by split air conditioning is quite low, that is 19-22 °C at the rate of 16-20 mL / min and it has PH balance. Under such conditions, Air Condensate produced by split air conditioning should still be recovered as an additional cooling medium on the condenser. This research will re-investigate the use of condensate water as an intermittent additional cooling of the condenser to increase the cooling capacity and performance of the air conditioning system. This research is done by experimental method whose implementation includes; designing and manufacturing of experimental equipment, mounting measuring tools, experimental data retrieval, data processing and yield analysis. The experimental results show that the use of condensate water as an intermittent additional cooling medium on split air conditioning condenser can increase the refrigeration effect about 2%, cooling capacity about 4% and 7% of COP system. Experimental results also show a decrease in power consumption in the system compressor about 3%

  17. Application of the Defense-in-Depth Concept in the Projects of New-Generation NPPs Equipped with VVER Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Shvyryaev, Yu. V.; Morozov, V. B.; Kuchumov, A.Yu., E-mail: morozov@aep.ru [JSC Atomenergoproekt, Moscow (Russian Federation)

    2014-10-15

    The projects of new-generation NPPs equipped with VVER reactors are developed as projects the safety level of which is superior to that of NPPs that are currently in operation. The main design solutions adopted for implementing the defence-in-depth (DiD) concept in the projects of new-generation NPPs equipped with VVER reactors are briefly characterized in the paper. (author)

  18. Greenhouse effect: effects on refrigerating and air conditioning industries; Effet de serre: impacts sur les professions du froid et de la climatisation

    Energy Technology Data Exchange (ETDEWEB)

    Le Boru, B. [Association Francaise de Froid, Alliance Froid Climatisation Environnement, 75 - Paris (France)

    1997-12-31

    The various factors (refrigerant characteristics, design and operating performance, insulation type, etc.) involved in greenhouse gas emission from refrigerating and air conditioning equipment are listed with the potential actions that may be taken at the different stages of equipment design, engineering, installation, operation, maintenance and dismantling, in order to reduce pollutant emissions

  19. Residential solar air conditioning: Energy and exergy analyses of an ammonia–water absorption cooling system

    International Nuclear Information System (INIS)

    Aman, J.; Ting, D.S.-K.; Henshaw, P.

    2014-01-01

    Large scale heat-driven absorption cooling systems are available in the marketplace for industrial applications but the concept of a solar driven absorption chiller for air-conditioning applications is relatively new. Absorption chillers have a lower efficiency than compression refrigeration systems, when used for small scale applications and this restrains the absorption cooling system from air conditioning applications in residential buildings. The potential of a solar driven ammonia–water absorption chiller for residential air conditioning application is discussed and analyzed in this paper. A thermodynamic model has been developed based on a 10 kW air cooled ammonia–water absorption chiller driven by solar thermal energy. Both energy and exergy analyses have been conducted to evaluate the performance of this residential scale cooling system. The analyses uncovered that the absorber is where the most exergy loss occurs (63%) followed by the generator (13%) and the condenser (11%). Furthermore, the exergy loss of the condenser and absorber greatly increase with temperature, the generator less so, and the exergy loss in the evaporator is the least sensitive to increasing temperature. -- Highlights: • 10 kW solar thermal driven ammonia–water air cooled absorption chiller is investigated. • Energy and exergy analyses have been done to enhance the thermal performance. • Low driving temperature heat sources have been optimized. • The efficiencies of the major components have been evaluated

  20. Feedback linearization based control of a variable air volume air conditioning system for cooling applications.

    Science.gov (United States)

    Thosar, Archana; Patra, Amit; Bhattacharyya, Souvik

    2008-07-01

    Design of a nonlinear control system for a Variable Air Volume Air Conditioning (VAVAC) plant through feedback linearization is presented in this article. VAVAC systems attempt to reduce building energy consumption while maintaining the primary role of air conditioning. The temperature of the space is maintained at a constant level by establishing a balance between the cooling load generated in the space and the air supply delivered to meet the load. The dynamic model of a VAVAC plant is derived and formulated as a MIMO bilinear system. Feedback linearization is applied for decoupling and linearization of the nonlinear model. Simulation results for a laboratory scale plant are presented to demonstrate the potential of keeping comfort and maintaining energy optimal performance by this methodology. Results obtained with a conventional PI controller and a feedback linearizing controller are compared and the superiority of the proposed approach is clearly established.

  1. A new method for controlling refrigerant flow in automobile air conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Xuquan Li; Jiangping Chen; Zhijiu Chen [Shanghai Jiao Tong University (China). Institute of Refrigeration and Cryogenics Engineering; Weihua Liu; Wei Hu; Xiaobing Liu [Shanghai Delphi Automotive Air Conditiong Systems Co. Ltd., Changhai (China)

    2004-05-01

    This paper describes the improvement of the refrigerant flow control method by using an electronic expansion valve (EEV) which is driven by a stepper motor in automobile air conditioning system. An EEV can make a quick response to the abrupt change in the refrigerant flow rate during the change in automobile speed and the thermostatic on/off operation. The flow rate characteristic of the EEV for automobile air conditioning was presented. A microcontroller is used to receive the input signal and generate the output signal to control the opening of the EEV. The fuzzy self-tuning proportional-integral-derivative (PID) control method is employed. Experimental results show that the new control method can feed adequate refrigerant flow into the evaporator in various operations. The evaporator discharge air temperature has dropped by approximately 3{sup o}C as compared with that of the conventional PID control system. (author)

  2. Generate floor response spectra, Part 2: Response spectra for equipment-structure resonance

    International Nuclear Information System (INIS)

    Li, Bo; Jiang, Wei; Xie, Wei-Chau; Pandey, Mahesh D.

    2015-01-01

    Highlights: • The concept of tRS is proposed to deal with tuning of equipment and structures. • Established statistical approaches for estimating tRS corresponding to given GRS. • Derived a new modal combination rule from the theory of random vibration. • Developed efficient and accurate direct method for generating floor response spectra. - Abstract: When generating floor response spectra (FRS) using the direct spectra-to-spectra method developed in the companion paper, probability distribution of t-response spectrum (tRS), which deals with equipment-structure resonance or tuning, corresponding to a specified ground response spectrum (GRS) is required. In this paper, simulation results using a large number of horizontal and vertical ground motions are employed to establish statistical relationships between tRS and GRS. It is observed that the influence of site conditions on horizontal statistical relationships is negligible, whereas the effect of site conditions on vertical statistical relationships cannot be ignored. Considering the influence of site conditions, horizontal statistical relationship suitable for all site conditions and vertical statistical relationships suitable for hard sites and soft sites, respectively, are established. The horizontal and vertical statistical relationships are suitable to estimate tRS for design spectra in USNRC R.G. 1.60 and NUREG/CR-0098, Uniform Hazard Spectra (UHS) in Western North America (WNA), or any GRS falling inside the valid coverage of the statistical relationship. For UHS with significant high frequency spectral accelerations, such as UHS in Central and Eastern North America (CENA), an amplification ratio method is proposed to estimate tRS. Numerical examples demonstrate that the statistical relationships and the amplification ratio method are acceptable to estimate tRS for given GRS and to generate FRS using the direct method in different practical situations.

  3. Generate floor response spectra, Part 2: Response spectra for equipment-structure resonance

    Energy Technology Data Exchange (ETDEWEB)

    Li, Bo, E-mail: b68li@uwaterloo.ca; Jiang, Wei, E-mail: w46jiang@uwaterloo.ca; Xie, Wei-Chau, E-mail: xie@uwaterloo.ca; Pandey, Mahesh D., E-mail: mdpandey@uwaterloo.ca

    2015-11-15

    Highlights: • The concept of tRS is proposed to deal with tuning of equipment and structures. • Established statistical approaches for estimating tRS corresponding to given GRS. • Derived a new modal combination rule from the theory of random vibration. • Developed efficient and accurate direct method for generating floor response spectra. - Abstract: When generating floor response spectra (FRS) using the direct spectra-to-spectra method developed in the companion paper, probability distribution of t-response spectrum (tRS), which deals with equipment-structure resonance or tuning, corresponding to a specified ground response spectrum (GRS) is required. In this paper, simulation results using a large number of horizontal and vertical ground motions are employed to establish statistical relationships between tRS and GRS. It is observed that the influence of site conditions on horizontal statistical relationships is negligible, whereas the effect of site conditions on vertical statistical relationships cannot be ignored. Considering the influence of site conditions, horizontal statistical relationship suitable for all site conditions and vertical statistical relationships suitable for hard sites and soft sites, respectively, are established. The horizontal and vertical statistical relationships are suitable to estimate tRS for design spectra in USNRC R.G. 1.60 and NUREG/CR-0098, Uniform Hazard Spectra (UHS) in Western North America (WNA), or any GRS falling inside the valid coverage of the statistical relationship. For UHS with significant high frequency spectral accelerations, such as UHS in Central and Eastern North America (CENA), an amplification ratio method is proposed to estimate tRS. Numerical examples demonstrate that the statistical relationships and the amplification ratio method are acceptable to estimate tRS for given GRS and to generate FRS using the direct method in different practical situations.

  4. Francisella guangzhouensis sp. nov., isolated from air-conditioning systems.

    Science.gov (United States)

    Qu, Ping-Hua; Chen, Shou-Yi; Scholz, Holger C; Busse, Hans-Jürgen; Gu, Quan; Kämpfer, Peter; Foster, Jeffrey T; Glaeser, Stefanie P; Chen, Cha; Yang, Zhi-Chong

    2013-10-01

    Four strains (08HL01032(T), 09HG994, 10HP82-6 and 10HL1960) were isolated from water of air-conditioning systems of various cooling towers in Guangzhou city, China. Cells were Gram-stain-negative coccobacilli without flagella, catalase-positive and oxidase-negative, showing no reduction of nitrate, no hydrolysis of urea and no production of H2S. Growth was characteristically enhanced in the presence of l-cysteine, which was consistent with the properties of members of the genus Francisella. The quinone system was composed of ubiquinone Q-8 with minor amounts of Q-9. The polar lipid profile consisted of the predominant lipids phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, two unidentified phospholipids (PL2, PL3), an unidentified aminophospholipid and an unidentified glycolipid (GL2). The polyamine pattern consisted of the major compounds spermidine, cadaverine and spermine. The major cellular fatty acids were C10 : 0, C14 : 0, C16 : 0, C18 : 1ω9c and C18 : 1 3-OH. A draft whole-genome sequence of the proposed type strain 08HL01032(T) was generated. Comparative sequence analysis of the complete 16S and 23S rRNA genes confirmed affiliation to the genus Francisella, with 95 % sequence identity to the closest relatives in the database, the type strains of Francisella philomiragia and Francisella noatunensis subsp. orientalis. Full-length deduced amino acid sequences of various housekeeping genes, recA, gyrB, groEL, dnaK, rpoA, rpoB, rpoD, rpoH, fopA and sdhA, exhibited similarities of 67-92 % to strains of other species of the genus Francisella. Strains 08HL01032(T), 09HG994, 10HP82-6 and 10HL1960 exhibited highly similar pan-genome PCR profiles. Both the phenotypic and molecular data support the conclusion that the four strains belong to the genus Francisella but exhibit considerable divergence from all recognized Francisella species. Therefore, we propose the name Francisella guangzhouensis sp

  5. Automobile air-conditioning its energy and environmental impact; La climatisation automobile impact energetique et environnemental

    Energy Technology Data Exchange (ETDEWEB)

    Barbusse, St.; Gagnepain, L.

    2003-05-01

    Over the last three decades, automobile manufacturers have made a lot of progress in specific fuel consumption and engine emissions of pollutants. Yet the impact of these improvements on vehicle consumption has been limited by increased dynamic performances (maxi-mum speed, torque), increased safety (power steering and power brakes) and increased comfort (noise and vibration reduction, electric windows and thermal comfort). Because of this, the real CO{sub 2}-emission levels in vehicles is still high in a context where road transport is a major factor in the balance sheet of greenhouse gas emissions, thus in complying with the inter-national climate convention. Although European, Japanese and Korean manufacturers signed an important agreement with the European Commission for voluntarily reducing CO{sub 2} emissions from their vehicles, with a weighted average emission goal by sales of 140 grams per km on the MVEG approval cycle by 2008, it has to be noted that the European procedures for measuring fuel consumption and CO{sub 2} emissions do not take accessories into account, especially air-condition ng (A/C). The big dissemination of this equipment recognized as a big energy consumer and as using a refrigerant with a high global warming potential ed ADEME to implement a set of assessments of A/C's energy and environmental impact. In particular these assessments include studies of vehicle equipment rates, analyses of impact on fuel consumption as well as regulated pollutant emissions in the exhaust, a characterization of the refrigerant leakage levels and an estimate of greenhouse gas emissions for all air-conditioned vehicles. This leaflet summarizes the results of these actions. All of these studies and additional data are presented in greater detail in the document,-'Automobile Air-conditioning' (ADEME reference no. 4985). (author)

  6. Design of Air Conditioning Automation for Patisserie Shopwindow

    OpenAIRE

    Kemal Tutuncu; Recai Ozcan

    2013-01-01

    Having done in this study, air-conditioning automation for patisserie shopwindow was designed. In the cooling sector it is quite important to cooling up the air temperature in the shopwindow within short time interval. Otherwise the patisseries inside of the shopwindow will be spoilt in a few days. Additionally the humidity is other important parameter for the patisseries kept in shopwindow. It must be raised up to desired level in a quite short time. Traditional patisser...

  7. Alternative air-conditioning with the use of solar energy

    International Nuclear Information System (INIS)

    Algarbi, N. M.

    2006-01-01

    The paper concerns the investigation of the alternative air condition systems on the basis of the open absorbtion cycle with the use of solar energy as a heat source. Schematic solution of systems has been carried. The design analysis of working characteristics was performed for a wide rang of initial parameters (teperature and humidity of ambient air, the type and concentration of liquid sorbents, etc.) and construction features of heat and mass transfer.(Author)

  8. Modelling of air-conditioned and heated spaces

    Energy Technology Data Exchange (ETDEWEB)

    Moehl, U

    1987-01-01

    A space represents a complex system involving numerous components, manipulated variables and disturbances which need to be described if dynamic behaviour of space air is to be determined. A justifiable amount of simulation input is determined by the application of adjusted modelling of the individual components. The determination of natural air exchange in heated spaces and of space-air flow in air-conditioned space are a primary source of uncertainties. (orig.).

  9. EIRP Characterization of Electrically Large Wireless Equipment with Integrated Signal Generator in a Compact Environment

    Directory of Open Access Journals (Sweden)

    Soon-Soo Oh

    2015-01-01

    Full Text Available We describe a measurement technique to characterize the equivalent isotropically radiated power (EIRP of electrically large wireless equipment in a compact environment. A modified phase-measurement method was proposed and, thus, the separation of the signal generator and radiating element was not required during the measurement. A Fresnel-to-far-field transformation was used for the fast measurement time in a compact anechoic chamber. An experimental verification of the method was carried out in a compact anechoic chamber, where the source-detector separation was approximately 1/5 of the far-field distance. The measured magnitude and phase pattern exhibited only a small error. The EIRP obtained using a Fresnel-to-far-field transformation was compared with a reference value, and the error was within 0.5 dB.

  10. Application of PSA in Designing New Third-Generation NPPs Equipped with VVE Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Kuchumov, A. Yu.; Morozov, V.B., E-mail: morozov-sloboda@mail.ru [JSC Atomenergoproekt, Moscow (Russian Federation)

    2014-10-15

    The projects of new third-generation NPPs shall meet more stringent safety requirements. A proper balance between a high level of safety and modern requirements for power unit availability indicators cannot be achieved without applying a probabilistic approach in the course of designing, central to which is probabilistic safety assessment (PSA). The report presents the main results from application of PSA in working out new projects of NPPs equipped with VVER reactors, as well as the obtained quantitative results reflecting the entire spectrum of operational states and initiating events. It is shown that by using an efficient combination of active and passive safety systems it is possible to achieve a safety level in the projects complying with the latest requirements, including those following from the lessons learnt from the Fukushima accident. (author)

  11. Benefits of Leapfrogging to Superefficiency and Low Global Warming Potential Refrigerants in Room Air Conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Nihar [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area; Wei, Max [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area; Letschert, Virginie [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area; Phadke, Amol [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area

    2015-10-01

    Hydrofluorocarbons (HFCs) emitted from uses such as refrigerants and thermal insulating foam, are now the fastest growing greenhouse gases (GHGs), with global warming potentials (GWP) thousands of times higher than carbon dioxide (CO2). Because of the short lifetime of these molecules in the atmosphere, mitigating the amount of these short-lived climate pollutants (SLCPs) provides a faster path to climate change mitigation than control of CO2 alone. This has led to proposals from Africa, Europe, India, Island States, and North America to amend the Montreal Protocol on Substances that Deplete the Ozone Layer (Montreal Protocol) to phase-down high-GWP HFCs. Simultaneously, energy efficiency market transformation programs such as standards, labeling and incentive programs are endeavoring to improve the energy efficiency for refrigeration and air conditioning equipment to provide life cycle cost, energy, GHG, and peak load savings. In this paper we provide an estimate of the magnitude of such GHG and peak electric load savings potential, for room air conditioning, if the refrigerant transition and energy efficiency improvement policies are implemented either separately or in parallel. We find that implementing HFC refrigerant transition and energy efficiency improvement policies in parallel for room air conditioning, roughly doubles the benefit of either policy implemented separately. We estimate that shifting the 2030 world stock of room air conditioners from the low efficiency technology using high-GWP refrigerants to higher efficiency technology and low-GWP refrigerants in parallel would save between 340-790 gigawatts (GW) of peak load globally, which is roughly equivalent to avoiding 680-1550 peak power plants of 500MW each. This would save 0.85 GT/year annually in China equivalent to over 8 Three Gorges dams and over 0.32 GT/year annually in India equivalent to roughly twice India’s 100GW solar mission target. While there is some uncertainty associated with

  12. Development of Fuzzy Logic Control for Vehicle Air Conditioning System

    Directory of Open Access Journals (Sweden)

    Henry Nasution

    2008-08-01

    Full Text Available A vehicle air conditioning system is experimentally investigated. Measurements were taken during the experimental period at a time interval of one minute for a set point temperature of 22, 23 and 24oC with internal heat loads of 0, 1 and 2 kW. The cabin temperature and the speed of the compressor were varied and the performance of the system, energy consumption and energy saving ware analyzed. The main objective of the experimental work is to evaluate the energy saving obtained when the fuzzy logic control (FLC algorithm, through an inverter, continuously regulates the compressor speed. It demonstrates better control of the compressor operation in terms of energy consumption as compared to the control by using a thermostat imposing On/Off cycles on the compressor at the nominal frequency of 50 Hz. The experimental set-up consists of original components from the air conditioning system of a compact passenger vehicle. The experimental results indicate that the proposed technique can save energy and improve indoor comfort significantly for vehicle air conditioning systems compared to the conventional (On/Off control technique.

  13. Sensory evaluation of heating and air conditioning systems

    Energy Technology Data Exchange (ETDEWEB)

    Evin, F.; Siekierski, E. [Electricite de France, Research and Development Division, Les Renardieres, Moret Sur Loing (France)

    2002-07-01

    Existing standards and models, such as ISO 7730 or the work of Fanger [Thermal Comfort], are not sufficient to characterise the satisfaction and pleasantness of end-users provided by heating or air conditioning systems. For this reason Electricite de France (EDF) has initiated a project with the aim of using sensory evaluation techniques in the design of HVAC systems. Sensory evaluation has been used for more than 30 years in the food industry, and now involves the cosmetics, the phone and the automotive industries. It is based on a dual evaluation: sensation measurements carried out by a small panel of trained expert assessors; preference studies performed by a large panel of representative consumers. A correlation between the data of both studies is then used to explain the preferences in terms of sensations (preference mapping). The first experiments performed in 1999 and 2000 have provided lists of descriptors of thermal sensation and acoustic sensation associated with heating and air conditioning appliances. They show that it is possible to define discriminative descriptors, to train a panel and to reliably quantify these descriptors. It is then possible to draw the sensory profiles of different heating, ventilation and air conditioning (HVAC) systems. The future experimental laboratory that EDF has decided to build is also presented, where the trained panels and end-users will evaluate the sensations and the preferences of real systems in eight 'realistic environmental chambers' designed, furnished and decorated like offices and flats. (author)

  14. Indoor air quality investigation at air-conditioned and non-air-conditioned markets in Hong Kong

    International Nuclear Information System (INIS)

    Guo, H.; Lee, S.C.; Chan, L.Y.

    2004-01-01

    To characterize indoor air quality at the markets in Hong Kong, three non-air-conditioned and two air-conditioned markets were selected for this study. The indoor air pollutants measured included PM 10 (particulate matters with aerodynamic diameter less than 10 μm), total bacteria count (TBC), carbon monoxide (CO), nitric oxide (NO), nitrogen dioxide (NO 2 ) and sulfur dioxide (SO 2 ). The indoor and outdoor concentrations of these target air pollutants at these markets were measured and compared. The effects of air conditioning, temperature/relative humidity variation and different stalls on the indoor air quality were also investigated. The results indicated that all of the average indoor concentrations of PM 10 , TBC, CO and NO 2 at the markets were below the Hong Kong Indoor Air Quality Objectives (HKIAQO) standards with a few exceptions for PM 10 and TBC. The elevated PM 10 concentrations at Hung Hom, Ngau Tau Kok and Wan Chai markets were probably due to the air filtration of outdoor airborne particulates emitted from vehicular exhaust, whereas high concentrations of airborne bacteria at Sai Ying Pun and Tin Shing markets were linked to the use of air conditioning. Correlation analysis demonstrated that indoor bacteria concentrations were correlated with temperature and relative humidity. The operation of air conditioning did not significantly reduce the levels of air pollutants at the markets. However, the higher indoor/outdoor ratios demonstrated that the operation of air conditioning had influence on the levels of bacteria at the markets. It was found that average PM 10 concentration at poultry stalls was higher than the HKIAQO standard of 180 μg/m 3 , and was over two times that measured at vegetable, fish and meat stalls. Furthermore, the concentration of airborne bacteria at the poultry stalls was as high as 1031 CFU/m 3 , which was above the HKIAQO standard of 1000 CFU/m 3 . The bacteria levels at other three stalls were all below the HKIAQO standard

  15. FY1999 Meeting of The Society of Heating, Air-Conditioning and Sanitary Engineering of Japan. Air flow analysis II; 1999 nendo gakujutsu koenkai gaiyo. Kiryu kaiseki 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-12-05

    B-4 reported the result on particle size distribution experiment and numerical calculation with FEM and {kappa}- {epsilon} model using a welding simulation equipment for generation and removal of welding fume in a narrow site. Discussion was held on the position of an exhaust hood. B-5 reported the study results on indoor air flow conditions derived from a movable nozzle air conditioning system by model experiment and numerical analysis. Disagreement of both results between the experiment and calculation in the case of two diffusing nozzles attached at 30 degrees toward the inside was improved by shortening a sampling time for calculation. B-6 reported the study results on some parameters such as wind velocity, flow rate and inlet position, and the energy saving effect of an air curtain (wall outlet, floor inlet) to control air conditioning areas for a part of large spaces by numerical analysis of air flow. Discussion was held on calculation of 2-D flow and layered flow. B-7 is the 5th research report on measurement of air flow conditions such as measurement of large space environment by video camera and balloon. Study on the camera for automatic measurement, and the identification technique of balloon positions was reported. (translated by NEDO)

  16. Thermodynamic analysis of an innovative liquid desiccant air conditioning system to supply potable water

    International Nuclear Information System (INIS)

    Ahmed, M.A.; Gandhidasan, P.; Zubair, Syed M.; Bahaidarah, Haitham M.

    2017-01-01

    Highlights: • The study objective is to reduce the energy consumption of desiccant AC system. • Heat and mass losses are recovered in the proposed system using a condenser. • The conventional and the proposed systems are compared in terms of COP. • The proposed system performance is better than the conventional system. • The proposed system produces freshwater in addition to space cooling. - Abstract: Liquid desiccant air conditioning systems are cost-effective, environmentally friendly and energy efficient techniques, especially in coastal areas. In the conventional liquid desiccant air conditioning system, the scavenging air is expelled into the atmosphere carrying a considerable amount of energy and water vapor. Thus, there is plenty of room to improve the system performance by recovering these losses. The proposed system consists of a conventional liquid desiccant air conditioning system plus a condenser. The aim of this study is to reduce the energy consumption by recovering the heat from the scavenging air using the condenser while also producing freshwater in addition to space cooling. Lithium chloride (LiCl) is used as the liquid desiccant for this study. The mathematical formulation for simultaneous heat and mass transfer between the condenser and the regenerator was developed to establish a comparison between the performance of the conventional and modified systems. Using the generated model, it is found that the modified system performance is 11.25% better than the conventional system and that it produces 86.4 kg of freshwater per hour as a by-product under the given conditions.

  17. Efficiency assessment of indoor environmental policy for air-conditioned offices in Hong Kong

    International Nuclear Information System (INIS)

    Wong, L.T.; Mui, K.W.

    2009-01-01

    To reduce carbon dioxide (CO 2 ) emissions through thermal energy conservation, air-conditioned offices in the subtropics are recommended to operate within specified ranges of indoor temperature, relative humidity and air velocity. As thermal discomfort leads to productivity loss, some indoor environmental policies for air-conditioned offices in Hong Kong are investigated in this study with relation to thermal energy consumption, CO 2 emissions from electricity use, and productivity loss due to thermal discomfort. Occupant thermal response is specifically considered as an adaptive factor in evaluating the energy consumption and productivity loss. The energy efficiency of an office is determined by the productivity which corresponds to the CO 2 generated. The results found that a policy with little impact on occupant thermal comfort and worker productivity would improve the office efficiency while the one with excessive energy consumption reduction would result in a substantial productivity loss. This study is a useful reference source for evaluating an indoor thermal environmental policy regarding the energy consumption, CO 2 emissions reduction, thermal comfort and productivity loss in air-conditioned offices in subtropical areas.

  18. Report of study 7.3: cooling and air conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Russo, F.

    2000-07-01

    This report describes the results of the study carried out by the study group 7.3 in the triennium 1997-2000. The study was focused on industrial refrigeration and air conditioning for the large building utilising natural gas. The goal of this study, carried out in collaboration of the members of study group 7.3, was to analyse the markets of industrial refrigeration and air conditioning for large buildings to identify possibilities to increase the natural gas share in these sectors. The available technology in the two sectors of the market are described in a single section, i.e. the 'State of the art of the technology'. In this section, technical characteristics, applications, performances, new developments and others topics are discussed for absorbers, gas engines, gas turbines and fuel cells. In the 'Industrial Refrigeration' section an analysis of the present global market for the industrial sector is presented. Economics, advantages and barriers to gas units compared with the electrical units are discussed. Information on existing industrial plants, possible application options and new technology developments are described as well. The 'Air conditioning for the large building' section deals with offices, hotels, commercial buildings, hospitals and shopping centres with a cooling capacity of 350 kW or higher. It appears that the use of natural gas for cooling of large buildings has been increasing during the last decade, thanks to the greater availability of natural gas and the development of new technologies. A marketing survey of gas air-conditioning was carried out in cooperation with a group of Intergas Marketing. Based on the survey, the report describes the market position of natural gas relative to electricity. It provides the strategic prospects for further developing natural gas as a competitive option for air-conditioning of large buildings using a combination of state-of-the-art technologies. It is important to highlight

  19. Development of air conditioning system and labor saving technology for efficient hydroponic cultivation; Konoritsuna suiko saibai no tame no kucho to shoryokuka gijutsu no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Okano, T.; Terazoe, H.; Shoji, K. [Central Research Institute of Electric Power Industry, Tokyo (Japan); Yonezawa, K.; Otani, F. [Chugoku Electric Power Co. Inc., Hiroshima (Japan); Sekiyama, T.; Kosakai, K.; Sato, H.

    1997-06-01

    Equipment which made experiments on air conditioning and hydroponic cultivation possible was set up at the technical research center of the Chugoku Electric Power Co., to study an air conditioning system using night power and energy saving technology for the cultivation. Vegetables suitable to the cultivation were selected. For air conditioning, adopted was a water heat storage air conditioning system using night power. The space between the shade curtain and the greenhouse roof was ventilated to prevent increase in cooling load caused by rise in curtain temperature. Moreover, the cultivation equipment was covered with transparent vinyl film to cool the inside of the equipment. The hydroponic cultivation equipment was trially manufactured which makes the continued production by one worker possible. The cultivation of spinach, leaf lettuce and chingensai throughout the year became possible. The yield of chingensai reached the target, but those of spinach and leaf lettuce were approximately 70% of the targets. Vegetables to be produced in the air-conditioned greenhouse by hydroponic cultivation are thought to be those that can have added values such non-pesticides and ingredients, young plants which were increased by cutting or tissue culturing, etc. 5 refs., 19 figs., 8 tabs.

  20. Thermal energy recovery of air conditioning system--heat recovery system calculation and phase change materials development

    International Nuclear Information System (INIS)

    Gu Zhaolin; Liu Hongjuan; Li Yun

    2004-01-01

    Latent heat thermal energy storage systems can be used to recover the rejected heat from air conditioning systems, which can be used to generate low-temperature hot water. It decreases not only the consumption of primary energy for heating domestic hot water but also the calefaction to the surroundings due to the rejection of heat from air conditioning systems. A recovery system using phase change materials (PCMs) to store the rejected (sensible and condensation) heat from air conditioning system has been developed and studied, making up the shortage of other sensible heat storage system. Also, PCMs compliant for heat recovery of air conditioning system should be developed. Technical grade paraffin wax has been discussed in this paper in order to develop a paraffin wax based PCM for the recovery of rejected heat from air conditioning systems. The thermal properties of technical grade paraffin wax and the mixtures of paraffin wax with lauric acid and with liquid paraffin (paraffin oil) are investigated and discussed, including volume expansion during the phase change process, the freezing point and the heat of fusion

  1. Magnetic Refrigeration Technology for High Efficiency Air Conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Boeder, A; Zimm, C

    2006-09-30

    Magnetic refrigeration was investigated as an efficient, environmentally friendly, flexible alternative to conventional residential vapor compression central air conditioning systems. Finite element analysis (FEA) models of advanced geometry active magnetic regenerator (AMR) beds were developed to minimize bed size and thus magnet mass by optimizing geometry for fluid flow and heat transfer and other losses. Conventional and magnetocaloric material (MCM) regenerator fabrication and assembly techniques were developed and advanced geometry passive regenerators were built and tested. A subscale engineering prototype (SEP) magnetic air conditioner was designed, constructed and tested. A model of the AMR cycle, combined with knowledge from passive regenerator experiments and FEA results, was used to design the regenerator beds. A 1.5 Tesla permanent magnet assembly was designed using FEA and the bed structure and plenum design was extensively optimized using FEA. The SEP is a flexible magnetic refrigeration platform, with individually instrumented beds and high flow rate and high frequency capability, although the current advanced regenerator geometry beds do not meet performance expectations, probably due to manufacturing and assembly tolerances. A model of the AMR cycle was used to optimize the design of a 3 ton capacity magnetic air conditioner, and the system design was iterated to minimize external parasitic losses such as heat exchanger pressure drop and fan power. The manufacturing cost for the entire air conditioning system was estimated, and while the estimated SEER efficiency is high, the magnetic air conditioning system is not cost competitive as currently configured. The 3 ton study results indicate that there are other applications where magnetic refrigeration is anticipated to have cost advantages over conventional systems, especially applications where magnetic refrigeration, through the use of its aqueous heat transfer fluid, could eliminate intermediate

  2. Liquid over-feeding air conditioning system and method

    Science.gov (United States)

    Mei, Viung C.; Chen, Fang C.

    1993-01-01

    A refrigeration air conditioning system utilizing a liquid over-feeding operation is described. A liquid refrigerant accumulator-heat exchanger is placed in the system to provide a heat exchange relationship between hot liquid refrigerant discharged from condenser and a relatively cool mixture of liquid and vaporous refrigerant discharged from the evaporator. This heat exchange relationship substantially sub-cools the hot liquid refrigerant which undergoes little or no evaporation across the expansion device and provides a liquid over-feeding operation through the evaporator for effectively using 100 percent of evaporator for cooling purposes and for providing the aforementioned mixture of liquid and vaporous refrigerant.

  3. Simulation of Artificial Intelligence for Automotive Air-conditioning System

    Institute of Scientific and Technical Information of China (English)

    YUAN Xiao-mei; CHEN You-hua; CHEN Zhi-jiu

    2002-01-01

    The artificial intelligence is applied to the simulation of the automotive air-conditioning system ( AACS )According to the system's characteristics a model of AACS, based on neural network, is developed. Different control methods of AACS are discussed through simulation based on this model. The result shows that the neural- fuzzy control is the best one compared with the on-off control and conventional fuzzy control method.It can make the compartment's temperature descend rapidly to the designed temperature and the fluctuation is small.

  4. Liquid over-feeding air conditioning system and method

    Science.gov (United States)

    Mei, V.C.; Chen, F.C.

    1993-09-21

    A refrigeration air conditioning system utilizing a liquid over-feeding operation is described. A liquid refrigerant accumulator-heat exchanger is placed in the system to provide a heat exchange relationship between hot liquid refrigerant discharged from condenser and a relatively cool mixture of liquid and vaporous refrigerant discharged from the evaporator. This heat exchange relationship substantially sub-cools the hot liquid refrigerant which undergoes little or no evaporation across the expansion device and provides a liquid over-feeding operation through the evaporator for effectively using 100 percent of evaporator for cooling purposes and for providing the aforementioned mixture of liquid and vaporous refrigerant. 1 figure.

  5. [Air quality control systems: heating, ventilating, and air conditioning (HVAC)].

    Science.gov (United States)

    Bellucci Sessa, R; Riccio, G

    2004-01-01

    After a brief illustration of the principal layout schemes of Heating, Ventilating, and Air Conditioning (HVAC), the first part of this paper summarizes the standards, both voluntary and compulsory, regulating HVAC facilities design and installation with regard to the question of Indoor Air Quality (IAQ). The paper then examines the problem of ventilation systems maintenance and the essential hygienistic requirements in whose absence HVAC facilities may become a risk factor for people working or living in the building. Lastly, the paper deals with HVAC design strategies and methods, which aim not only to satisfy comfort and air quality requirements, but also to ensure easy and effective maintenance procedures.

  6. Acanthamoeba belonging to T3, T4, and T11: genotypes isolated from air-conditioning units in Santiago, Chile.

    Science.gov (United States)

    Astorga, Berbeli; Lorenzo-Morales, Jacob; Martín-Navarro, Carmen M; Alarcón, Verónica; Moreno, Johanna; González, Ana C; Navarrete, Elizabeth; Piñero, José E; Valladares, Basilio

    2011-01-01

    Free-living amoebae (FLA) of the genus Acanthamoeba are widely distributed in the environment, in the air, soil, and water, and have also been isolated from air-conditioning units. The objective of this work was to investigate the presence of this genus of FLA in the air-conditioning equipment at the Institute of Public Health of Chile in Santiago, Chile. Water and air samples were collected from air-conditioning systems and were checked for the presence of Acanthamoeba spp. Positive samples were further classified at the genotype level after sequencing the highly variable diagnostic fragment 3 (DF3) region of the 18S rRNA gene. This is the first report of the T3, T4, and T11 genotypes of Acanthamoeba in air-conditioning units from Chile. Overall, the widespread distribution of potentially pathogenic Acanthamoeba strains in the studied source demands more awareness within the public and health professionals in Chile as this pathogen is emerging as a risk for human health worldwide. © 2011 The Author(s) Journal of Eukaryotic Microbiology © 2011 International Society of Protistologists.

  7. Heat transfer characteristics in a sudden expansion pipe equipped with swirl generators

    International Nuclear Information System (INIS)

    Zohir, A.E.; Abdel Aziz, A.A.; Habib, M.A.

    2011-01-01

    This investigation is aimed at studying the heat transfer characteristics and pressure drop for turbulent airflow in a sudden expansion pipe equipped with propeller type swirl generator or spiral spring with several pitch ratios. The investigation is performed for the Reynolds number ranging from 7500 to 18,500 under a uniform heat flux condition. The experiments are also undertaken for three locations for the propeller fan (N = 15 blades and blade angle of 65 o ) and three pitch ratios for the spiral spring (P/D = 10, 15 and 20). The influences of using the propeller rotating freely and inserted spiral spring on heat transfer enhancement and pressure drop are reported. In the experiments, the swirl generator and spiral spring are used to create a swirl in the tube flow. Mean and relative mean Nusselt numbers are determined and compared with those obtained from other similar cases. The experimental results indicate that the tube with the propeller inserts provides considerable improvement of the heat transfer rate over the plain tube around 1.69 times for X/H = 5. While for the tube with the spiral spring inserts, an improvement of the heat transfer rate over the plain tube around 1.37 times for P/d = 20. Thus, because of strong swirl or rotating flow, the propeller location and the spiral spring pitch become influential on the heat transfer enhancement. The increase in pressure drop using the propeller is found to be three times and for spiral spring 1.5 times over the plain tube. Correlations for mean Nusselt number, fan location and spiral spring pitch are provided.

  8. FASTBUS standard for development of the 4th generation fastresponse electronic equipment

    International Nuclear Information System (INIS)

    Basiladze, S.G.

    1982-01-01

    Design features are considered of a new FASTBUS electronic equipment developed for use as structural-logical and constructional base for multi-channel fast-response nuclear-physical measurement system of the fourth generation. A description is given of procedure of the data exchange between modules, ways of addressing (geographical, logical, broadcast transaction), acknowledgement of grant, controlling and informative registers, purpose of data-control buses and auxiliary logic, segment interconnect arrangement, organizat:on of interruptions and controlblock data transmission, arrangement of processor interfaces, snoop modules and diagnostics modules. A comparison between the FASTBUS standard and CAMAC system widely used nowadays shows that in the CAMAC standard the crate trunk and branch utilize quite different exchange logic, whereas in the FASTBUS standard it is unique. The CAMAC system cycle is strictly timed. The FASTBUS standard is not restricted for the module fast response, as it operates in the request-response mode. A conclusion is drawn to the effect that the FASTBUS standard advantages are most fully realized in on-line processing of large volumes of initial data

  9. Impact of Auxiliary Equipments Consumption on Electricity Generation Cost in Selected Power Plants of Pakistan

    Directory of Open Access Journals (Sweden)

    DILEEP KUMAR

    2017-04-01

    Full Text Available This study focuses on higher generation cost of electricity in selected TPPs (Thermal Power Plants in Sindh, Pakistan. It also investigates the energy consumed by the auxiliary equipment of the selected TPPs in Sindh, Pakistan. The AC (Auxiliary Consumption of selected TPPs is compared with that in UK and other developed countries. Results show that the AC in selected TPPs in Sindh, Pakistan exceeds the average AC of the TPPs situated in developed countries. Many energy conservation measures such as impeller trimming and de-staging, boiler feed pump, high voltage inverter, variable frequency drive, and upgrading the existing cooling tower fan blades with fiber reinforced plastic are discussed to overcome higher AC. This study shows that harnessing various available energy conservative measures the AC and unit cost can be reduced by 4.13 and 8.8%; also adverse environmental impacts can be mitigated. Results show that the unit cost of electricity can be reduced from Rs.20 to19/kWh in JTPP (Jamshoro Thermal Power Plant, Rs.9 to 8.8/kWh in GTPS (Gas Turbine Power Station Kotri and Rs. 11 to 10.27/ kWh in LPS (Lakhara Power Station. Thus, electricity production can be improved with the existing capacity, which will eventually assist to manage the current energy crisis and ensure its conservation

  10. System monitoring feedback in cinemas and harvesting energy of the air conditioning condenser

    Science.gov (United States)

    Pop, P. P.; Pop-Vadean, A.; Barz, C.; Latinovic, T.; Chiver, O.

    2017-05-01

    Our article monitors the degree of emotional involvement of the audience in the action film in theaters by measuring the concentration of CO2. The software performs data processing obtained dispersion sensors and displays data during the film. The software will also trigger the start of the air conditioning condenser where we can get harvesting energy by installing a piezoelectric device. Useful energy can be recovered from various waste produced in cinema. The time lag between actions and changes in environmental systems determines that decisions made now will affect subsequent generations and the future of our environment.

  11. The effect of environmental parameters to dust concentration in air-conditioned space

    Science.gov (United States)

    Ismail, A. M. M.; Manssor, N. A. S.; Nalisa, A.; Yahaya, N.

    2017-08-01

    Malaysia has a wet and hot climate, therefore most of the spaces are air conditioned. The environment might affect dust concentration inside a space and affect the indoor air quality (IAQ). The main objective of this study is to study the dust concentration collected inside enclosed air-conditioned space. The measurement was done physically at four selected offices and two classrooms using a number of equipment to measure the dust concentration and environmental parameters which are temperature and relative air humidity. It was found that the highest dust concentration produced in office (temperature of 24.7°C, relative humidity of 66.5%) is 0.075 mg/m3, as compared to classroom, the highest dust concentration produced is 0.060 mg/m3 office (temperature of 25.9°C, relative humidity of 64.0%). However, both measurements show that value still within the safety level set by DOSH Malaysia (2005-2010) and ASHRAE 62.2 2016. The office contained higher dust concentration compared to classroom because of frequent movement transpires daily due to the functional of the offices.

  12. Benefits of Leapfrogging to Superefficiency and Low Global Warming Potential Refrigerants in Room Air Conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Nihar K. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wei, Max [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Letschert, Virginie [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Phadke, Amol A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-10-01

    Hydrofluorocarbons (HFCs) emitted from uses such as refrigerants and thermal insulating foam, are now the fastest growing greenhouse gases (GHGs), with global warming potentials (GWP) thousands of times higher than carbon dioxide (CO2). Because of the short lifetime of these molecules in the atmosphere,1 mitigating the amount of these short-lived climate pollutants (SLCPs) provides a faster path to climate change mitigation than control of CO2 alone. This has led to proposals from Africa, Europe, India, Island States, and North America to amend the Montreal Protocol on Substances that Deplete the Ozone Layer (Montreal Protocol) to phase-down high-GWP HFCs. Simultaneously, energy efficiency market transformation programs such as standards, labeling and incentive programs are endeavoring to improve the energy efficiency for refrigeration and air conditioning equipment to provide life cycle cost, energy, GHG, and peak load savings. In this paper we provide an estimate of the magnitude of such GHG and peak electric load savings potential, for room air conditioning, if the refrigerant transition and energy efficiency improvement policies are implemented either separately or in parallel.

  13. [Airborne Fungal Aerosol Concentration and Distribution Characteristics in Air- Conditioned Wards].

    Science.gov (United States)

    Zhang, Hua-ling; Feng, He-hua; Fang, Zi-liang; Wang, Ben-dong; Li, Dan

    2015-04-01

    The effects of airborne fungus on human health in the hospital environment are related to not only their genera and concentrations, but also their particle sizes and distribution characteristics. Moreover, the mechanisms of aerosols with different particle sizes on human health are different. Fungal samples were obtained in medicine wards of Chongqing using a six-stage sampler. The airborne fungal concentrations, genera and size distributions of all the sampling wards were investigated and identified in detail. Results showed that airborne fungal concentrations were not correlated to the diseases or personnel density, but were related to seasons, temperature, and relative humidity. The size distribution rule had roughly the same for testing wards in winter and summer. The size distributions were not related with diseases and seasons, the percentage of airborne fungal concentrations increased gradually from stage I to stage III, and then decreased dramatically from stage V to stage VI, in general, the size of airborne fungi was a normal distribution. There was no markedly difference for median diameter of airborne fungi which was less 3.19 μm in these wards. There were similar dominant genera in all wards. They were Aspergillus spp, Penicillium spp and Alternaria spp. Therefore, attention should be paid to improve the filtration efficiency of particle size of 1.1-4.7 μm for air conditioning system of wards. It also should be targeted to choose appropriate antibacterial methods and equipment for daily hygiene and air conditioning system operation management.

  14. An optimization strategy for the control of small capacity heat pump integrated air-conditioning system

    International Nuclear Information System (INIS)

    Gao, Jiajia; Huang, Gongsheng; Xu, Xinhua

    2016-01-01

    Highlights: • An optimization strategy for a small-scale air-conditioning system is developed. • The optimization strategy aims at optimizing the overall system energy consumption. • The strategy may guarantee the robust control of the space air temperature. • The performance of the optimization strategy was tested on a simulation platform. - Abstract: This paper studies the optimization of a small-scale central air-conditioning system, in which the cooling is provided by a ground source heat pump (GSHP) equipped with an on/off capacity control. The optimization strategy aims to optimize the overall system energy consumption and simultaneously guarantee the robustness of the space air temperature control without violating the allowed GSHP maximum start-ups number per hour specified by customers. The set-point of the chilled water return temperature and the width of the water temperature control band are used as the decision variables for the optimization. The performance of the proposed strategy was tested on a simulation platform. Results show that the optimization strategy can save the energy consumption by 9.59% in a typical spring day and 2.97% in a typical summer day. Meanwhile it is able to enhance the space air temperature control robustness when compared with a basic control strategy without optimization.

  15. Comparison of desiccant air conditioning systems with different indirect evaporative air coolers

    International Nuclear Information System (INIS)

    Pandelidis, Demis; Anisimov, Sergey; Worek, William M.; Drąg, Paweł

    2016-01-01

    Highlights: • A numerical study of desiccant air conditioning systems is presented. • The ε-NTU model is used for the analysis. • Different arrangements of the desiccant systems were compared. • The systems were compared under different operating conditions. - Abstract: This paper presents a numerical analysis of three desiccant air-conditioning systems equipped with different indirect evaporative air coolers: (1) the cross-flow Maisotsenko cycle heat and mass exchanger (HMX), (2) the regenerative counter-flow Maisotsenko cycle heat and mass exchanger and (3) the standard cross-flow evaporative air cooler. To analyze the desiccant wheel and the indirect evaporative air coolers, the modified ε-NTU-model was used. The simulations were performed under assumption that the desiccant wheel is regenerated with air heated to relatively low temperature values (50–60 °C), which can be produced with solar panels in typical moderate climatic conditions. It was established that the main advantage of the presented solutions is that they can provide comfort conditions even with less effective dehumidification. The different systems were compared under variable selected operational factors (i.e. inlet air temperature, humidity and regeneration air temperature). The analysis allowed establishing the advantages and disadvantages of presented solutions and allowed estimating their application potential.

  16. 2017 German refrigeration and air conditioning meeting. Proceedings

    International Nuclear Information System (INIS)

    2017-01-01

    This year's lecture programme includes 117 presentations in the five working departments of DKV and 10 lectures at the special event ''Energy-efficient air conditioning in data centres''. The main topics in the respective departments were: (1) Cryogenics: Space applications; Cryogenic plants; Cryomedicine and cryobiology; Components, developments; Processes and plants; Valves, design. (2) Basics: Evaporation, material values; evaporation, condensation; absorption; adsorption, latent storage; cycle simulation. (3) Components: CO 2 plant engineering and components; refrigerants; process control, adsorption, sublimation and storage technology; refrigerating machine oils, heat exchangers and corrosion; components 4.0, sensors and control technology; simulation of plant processes. (4) Cold application: Application; Application / Natural Refrigerants; Mobile Applications Car; Mobile Applications; Supermarket / Efficiency; Optimization / Efficiency. (5) Air conditioning and heat pump applications: load shifting, smart home, flexibility; heat sources and industrial heat pumps; modelling, simulations; energy concepts heat pumps and photovoltaics; monitoring, evaluation; technology trends / working materials. Six papers are separately analyzed for this database. [de

  17. Performance enhancement of a subcooled cold storage air conditioning system

    International Nuclear Information System (INIS)

    Hsiao, M.-J.; Cheng, C.-H.; Huang, M.-C.; Chen, S.-L.

    2009-01-01

    This article experimentally investigates the enhancement of thermal performance for an air conditioning system utilizing a cold storage unit as a subcooler. The cold storage unit is composed of an energy storage tank, liquid-side heat exchanger, suction-side heat exchanger and energy storage material (ESM), water. When the cooling load is lower than the nominal cooling capacity of the system, the cold storage unit can store extra cold energy of the system to subcool the condenser outlet refrigerant. Hence, both the cooling capacity and coefficient of performance (COP) of the system will be increased. This experiment tests the two operation modes: subcooled mode with energy storage and non-subcooled mode without energy storage. The results show that for fixed cooling loads at 3.05 kW, 3.5 kW and 3.95 kW, the COP of the subcooled mode are 16.0%, 15.6% and 14.1% higher than those of the non-subcooled mode, respectively. In the varied cooling load experiments, the COP of the subcooled cold storage air conditioning system is 15.3% higher than the conventional system.

  18. Analysis on a hybrid desiccant air-conditioning system

    International Nuclear Information System (INIS)

    Jia, C.X.; Dai, Y.J.; Wu, J.Y.; Wang, R.Z.

    2006-01-01

    Hybrid desiccant-assisted preconditioner and split cooling coil system, which combines the merits of moisture removal by desiccant and cooling coil for sensible heat removal, is a potential alternative to conventional vapor compression cooling systems. In this paper, experiments on a hybrid desiccant air-conditioning system, which is actually an integration of a rotary solid desiccant dehumidification and a vapor compression air-conditioning unit, had been carried out. It is found that, compared with the conventional VC (vapor compression) system, the hybrid desiccant cooling system economizes 37.5% electricity powers when the process air temperature and relative humidity are maintained at 30 o C, and 55% respectively. The reason why the hybrid desiccant cooling system features better performance relative to the VC system lies in the improvement brought about in the performance of the evaporator in VC unit due to desiccant dehumidification. A thermodynamic model of the hybrid desiccant system with R-22 as the refrigerant has been developed and the impact of operating parameters on the sensible heat ratio of the evaporator and the electric power saving rate has been analyzed. It is found that a majority of evaporators can operate in the dry condition even if the regeneration temperature is lower (i.e. 80 o C)

  19. Flow and air conditioning simulations of computer turbinectomized nose models.

    Science.gov (United States)

    Pérez-Mota, J; Solorio-Ordaz, F; Cervantes-de Gortari, J

    2018-04-16

    Air conditioning for the human respiratory system is the most important function of the nose. When obstruction occurs in the nasal airway, turbinectomy is used to correct such pathology. However, mucosal atrophy may occur sometime after this surgery when it is overdone. There is not enough information about long-term recovery of nasal air conditioning performance after partial or total surgery. The purpose of this research was to assess if, based on the flow and temperature/humidity characteristics of the air intake to the choana, partial resection of turbinates is better than total resection. A normal nasal cavity geometry was digitized from tomographic scans and a model was printed in 3D. Dynamic (sinusoidal) laboratory tests and computer simulations of airflow were conducted with full agreement between numerical and experimental results. Computational adaptations were subsequently performed to represent six turbinectomy variations and a swollen nasal cavity case. Streamlines along the nasal cavity and temperature and humidity distributions at the choana indicated that the middle turbinate partial resection is the best alternative. These findings may facilitate the diagnosis of nasal obstruction and can be useful both to plan a turbinectomy and to reduce postoperative discomfort. Graphical Abstract ᅟ.

  20. Measurement of Vehicle Air Conditioning Pull-Down Period

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, John F [ORNL; Huff, Shean P [ORNL; Moore, Larry G [ORNL; West, Brian H [ORNL

    2016-08-01

    Air conditioner usage was characterized for high heat-load summer conditions during short driving trips using a 2009 Ford Explorer and a 2009 Toyota Corolla. Vehicles were parked in the sun with windows closed to allow the cabin to become hot. Experiments were conducted by entering the instrumented vehicles in this heated condition and driving on-road with the windows up and the air conditioning set to maximum cooling, maximum fan speed and the air flow setting to recirculate cabin air rather than pull in outside humid air. The main purpose was to determine the length of time the air conditioner system would remain at or very near maximum cooling power under these severe-duty conditions. Because of the variable and somewhat uncontrolled nature of the experiments, they serve only to show that for short vehicle trips, air conditioning can remain near or at full cooling capacity for 10-minutes or significantly longer and the cabin may be uncomfortably warm during much of this time.

  1. Development in fiscal 1999 of technologies to put photovoltaic power generation systems into practical use. International cooperation projects (Collection of information on IEA photovoltaic air conditioning and hot water supply program); 1999 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Kokusai kyoryoku jigyo (IEA taiyo reidanbo kyuto program ni kansuru joho shushu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    This paper reports activities of collecting items of information by dispatching experts mainly composed of members of the IEA photovoltaic air conditioning, and solar heating and cooling program (SHCP) committee to the SHCP Executive Committee and the Task expert conferences. This treaty is intended to assist creating the environmentally sustainable future by utilizing solar designs and technologies. It also aims at developing solar technologies including cost reduction as a result of the joint researches with business entities, structuring international markets, providing items of information, quantifying the effectiveness to the environment, performing the international standardization, and promoting utilization of solar technologies in developing countries. The tasks now in action include architectural lighting, methods for analyzing solar architectural energies, optimization of solar energy utilization in large buildings, procurement of active solar systems, air conditioning systems in buildings using the solar energy, solar heat composite systems, expansion of exterior component materials for solar buildings, sustainable buildings, agricultural solar drying, solar cities, a hybrid heat/PV solar system. (NEDO)

  2. Modern methods of overlay welding for corrosion protection of power generating equipment

    International Nuclear Information System (INIS)

    Ershov, A.V.; Shul'man, I.E.; Potapov, N.N.

    1989-01-01

    Methods for overlay welding of inner surfaces of power equipment for corrosion protection are analysed. Various methods of electroslag overlay welding by a band electrode (overlay welding by two-electrode bands by a wide band with magnetic control, by an electrode band with high melting velocity) are marked to be the most perspective for cladding of NPP vessel equipment

  3. Data-Driven Scenario Generation for Enhanced Realism of Equipment Training Simulators

    NARCIS (Netherlands)

    Vahdatikhaki, Faridaddin; Hammad, Amin; olde Scholtenhuis, Léon Luc; Miller, Seirgei Rosario; Makarov, Denis

    2017-01-01

    Improving the training of heavy equipment operators can make a significant contribution to improving the safety of construction sites. In recent years, Virtual Reality (VR)-based simulators have gained increased popularity for the use in equipment training programs. While VR training simulators for

  4. Preventive maintenance plan of the air-conditioning duct using the ACM-sensor

    International Nuclear Information System (INIS)

    Fukuba, Kazushi; Ito, Takanobu; Kojima, Akiko; Tanji, Kazuhiro; Sato, Yuki

    2013-01-01

    Air-conditioning duct is difficult to predict the date to occur of corrosion such as affect the function. Therefore, the current conservation method is mostly corrective maintenance. Therefore, we used the test pieces of six types and ACM-sensor in order to solve the corrosion speed from corrosion environment and relationship of corrosion quantity of test pieces. In addition, was used the duct molded articles various in order to check the corrosion degree of when processed the duct. As a result, we were selected crust body constituting a duct and optimal combination of the flange by solve the corrosion speed of the test pieces various. Thus, it performs preventive disposal before to occur of corrosion such as affect the function by predicting the duct life from corrosion speed, and lead to stability and safe operating by appropriate maintenance of equipment. (author)

  5. Capillary Tube and Thermostatic Expansion Valve Comparative Analysis in Water Chiller Air Conditioning

    Science.gov (United States)

    Wijaya Sunu, Putu; Made Rasta, I.; Anakottapary, Daud Simon; Made Suarta, I.; Cipta Santosa, I. D. M.

    2018-01-01

    The aims of this study to compares the performance characteristics of a water chiller air conditioning simulation equipped with thermostatic expansion valve (TEV) with those of a capillary tube. Water chiller system filled with the same charge of refrigerant. Comparative analyses were performed based on coefficient of performance (COP) and performance parameter of the refrigeration system, carried out at medium cooling load level with the ambient temperature of 29-31°C, constant compressor speed and fixed chilled water volume flowrate at 15 lpm. It was shown that the TEV system showed better energy consumption compared to that of capillary tube. From the coefficient of performance perspective, the thermostatic expansion valve system showed higher COP (± 21.4%) compared to that of capillary tube system.

  6. CHARACTERIZATION OF OZONE EMISSIONS FROM AIR CLEANERS EQUIPPED WITH OZONE GENERATORS AND SENSOR AND FEEDBACK CONTROL CIRCUITRY

    Science.gov (United States)

    The paper give results of a characterization of ozone emissions from air cleaners equipped with ozone generators and sensor and feedback control circuitry. Ozone emission rates of several consumer appliances, marketed as indoor air treatment or air purification systems, were det...

  7. Device for positioning and generation of an element of track model and slice of the MELAS automatic equipment

    International Nuclear Information System (INIS)

    Kryutchenko, E.V.; Fedotov, V.S.

    1979-01-01

    The structure and organization of the device for positioning and generation of element of track model and slice of the MELAS automatic equipment which is developed for measuring films from big bubble chambers, is described. Main features of the device are studied and characteristics are given as well

  8. A study of alternative refrigerants for the refrigeration and air conditioning sector in Mauritius

    Science.gov (United States)

    Dreepaul, R. K.

    2017-11-01

    The most frequently used refrigerants in the refrigeration and air conditioning (RAC) sector in Mauritius are currently hydrochlorofluorocarbons (HCFC) and hydrofluorocarbons (HFC). However, because of their strong influence on global warming and the impact of HCFCs on the ozone layer, refrigerants such as ammonia (NH3), carbon dioxide (CO2) and Hydrocarbons (HC), having minimal impact on the environment, are being considered. So far, HCs have only been safely used in domestic refrigeration. Ammonia has been used mainly for industrial refrigeration whereas CO2 is still under study. In this paper, a comparative study of the various feasible alternatives is presented in a survey that was undertaken with major stake holders in the field. The retrofitting possibility of existing equipment was assessed and safety issues associated with each refrigerant were analysed. The major setback of hydrocarbons as a widely accepted refrigerant is its flammability which was considered as a major safety hazard by the majority of respondents in the survey and the main advantages are the improved equipment coefficient of performance (COP) and better TEWI factor. This resulted in a 12 % drop in energy consumption. Despite the excellent thermodynamic properties of ammonia, its use has mainly been confined to industrial refrigeration due to its toxicity. In Mauritius, the performance of ammonia in air conditioning is being evaluated on a pilot basis. The major setback of carbon dioxide as a refrigerant is the high operating pressure which is considered a safety hazard. The high initial investment cost and the lack of qualified maintenance technician is also an issue. The use of CO2 is mainly being considered in the commercial refrigeration sector.

  9. 8th International Symposium on Heating, Ventilation and Air Conditioning

    CERN Document Server

    Zhu, Yingxin; Li, Yuguo; Vol.1 Indoor and Outdoor Environment; Vol.2 HVAC&R Component and Energy System; Vol.3 Building Simulation and Information Management

    2014-01-01

    Proceedings of the 8th International Symposium on Heating, Ventilation and Air Conditioning is based on the 8th International Symposium of the same name (ISHVAC2013), which took place in Xi’an on October 19-21, 2013. The conference series was initiated at Tsinghua University in 1991 and has since become the premier international HVAC conference initiated in China, playing a significant part in the development of HVAC and indoor environmental research and industry around the world. This international conference provided an exclusive opportunity for policy-makers, designers, researchers, engineers and managers to share their experience. Considering the recent attention on building energy consumption and indoor environments, ISHVAC2013 provided a global platform for discussing recent research on and developments in different aspects of HVAC systems and components, with a focus on building energy consumption, energy efficiency and indoor environments. These categories span a broad range of topics, and the proce...

  10. Guidelines on Thermal Comfort of Air Conditioned Indoor Environment

    Science.gov (United States)

    Miura, Toyohiko

    The thermal comfort of air conditioned indoor environment for workers depended, of course, on metabolic rate of work, race, sex, age, clothing, climate of the district and state of acclimatization. The attention of the author was directed to the seasonal variation and the sexual difference of comfortable temperature and a survey through a year was conducted on the thermal comfort, and health conditions of workers engaged in light work in a precision machine factory, in some office workers. Besides, a series of experiments were conducted for purpose of determinning the optimum temperature of cooling in summer time in relation to the outdoor temperature. It seemed that many of workers at present would prefer somewhat higher temperature than those before the World War II. Forty years ago the average homes and offices were not so well heated as today, and clothing worn on the average was considerably heavier.

  11. Study of the test method for prediction of air conditioning equipment seasonal performance

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, S.B.

    1980-05-01

    The test procedure, Method of Testing, Rating and Estimating the Seasonal Performance of Central Air-Conditioners and Heat Pumps Operating in the Cooling Mode, has been analyzed. The analysis of the test procedure incorporated two main functions: (1) to determine the validity of the test procedure; and (2) to determine if there are other alternate methods of obtaining the same results with less testing burden. Data were collected from industry and analyzed for any significant trends. Certain conclusions are drawn about the energy efficiency ratios, degradation coefficients and seasonal energy efficiency ratios. An error analysis was performed on the test procedure to determine the approximate amount of error when using this procedure. A semi-empirical model assuming a first order system response was developed to determine the factors that affect the part-load and cooling-load factors. The corresponding transient characteristics are then determined in terms of a single time constant. A thermostat demand cycle is used to determine the relationship between on-time and cycle-time. Recommendations are made regarding an alternate method being used to determine the seasonal energy efficiency ratio.

  12. Users Guide to Direct Digital Control of Heating, Ventilating, and Air Conditioning Equipment,

    Science.gov (United States)

    1985-01-01

    cycles, reset, load shedding, chiller optimization , VAV fan synchronization, and optimum start/stop. The prospective buyer of a DDC system should...in Fig- ure 4. Data on setpoints , reset schedules, and event timing, such as that presented in Figure 6, are often even more difficult to find. In con...control logic, setpoint and other data are readily available. Program logic, setpoint and schedule data, and other information stored in a DDC unit

  13. Direct Digital Control of HVAC (Heating, Ventilating, and Air Conditioning Equipment (User’s Guide)

    Science.gov (United States)

    1985-01-01

    reset, load shedding, chiller optimization , VAV fan synchronization, and optimum start/stop. The prospective buyer of a DDC system should investigate...current and accurate drawings for a conventional, built-up control system such as that illustrated in Fig- ure 4. Data on setpoints , reset schedules, and...are always available in the form of the computer program code (Figure 7). In addition to the control logic, setpoint and other data are readily

  14. Evaluation of rotor-bearing system dynamic response to unbalance. [air conditioning equipment

    Science.gov (United States)

    Thaller, R. E.; Ozimek, D. W.

    1979-01-01

    The vibration environment within air conditioner rotating machinery referred to as an air cycle machine (ACM) was investigated to effectively increase ACM reliability. To assist in the selection of design changes which would result in improved ACM performance, various design modifications were incorporated into a baseline ACM configuration. For each design change, testing was conducted with the best balance achieveable (baseline) and with various degrees of unbalance. Relationships between unbalance (within the context of design changes) and the parameters associated with design goals were established. The results of rotor dynamics tests used to establish these relationships are presented.

  15. Air Conditioner Charging. Automotive Mechanics. Air Conditioning. Instructor's Guide [and] Student Guide.

    Science.gov (United States)

    Spignesi, B.

    This instructional package, one in a series of individualized instructional units on automobile air conditioning, consists of a student guide and an instructor guide dealing with air conditioning charging. Covered in the module are checking the air conditioning system for leaks, checking and adding refrigerant oil as needed, evacuating the system,…

  16. Ionizing secondary radiation generated by analog radiological and digital coronary cine angiographic equipment. Influence of external protection devices

    International Nuclear Information System (INIS)

    Ramirez N, Alfredo; Farias Ch, Eric; Silva J, Ana Maria; Leyton L, Fernando; Oyarzun C, Carlos; Ugalde P, Hector; Dussaillant, Gaston; Cumsille G, Angel

    2000-01-01

    Exposure to ionizing radiation is a know hazard of radiological procedures. Aim: to compare the emission of secondary ionizing radiation from two coronary angiographic equipments, one with digital and the other with analog image generation. To evaluate the effectiveness of external radiological protection devices. Material and methods: environmental and fluoroscopy generated radiation in the cephalic region of the patient was measured during diagnostic coronary angiographies. Ionizing radiation generated in anterior left oblique protection (ALO) and anterior right oblique protection (ARO) were measured with and without leaded protections. In 19 patients (group 1), a digital equipment was used and in 21 (group 2), an analog equipment. Results: header radiation for group 1 and 2 was 1194±337 and 364±222 μGray/h respectively (p≤0.001). During fluoroscopy and with leaded protection generated radiation for groups 1 and 2 was 612±947 and 70±61μGray/h respectively (p≤0.001). For ALO projection, generated for groups 1 and 2 was 105±47 and 71±192 μGray/h respectively (p≤0.001). During filming the radiation for ALO projection for groups 1 and 2 was 7252±9569 and 1671±2038 μGray/h respectively (p=0.03). Out of the protection zone, registered radiation during fluoroscopy for groups 1 and 2 was 2800±1741 and 1318±954 μGray/h respectively (p≤0.001); during filming, the figures were 15500±5840 and 18961±10599 μGray/h respectively (NS). Conclusions: digital radiological equipment has a lower level of ionizing radiation emission than the analog equipment

  17. Relationship between the merit factor of thermoelectric materials and the air conditioning unit of urban electric cars

    International Nuclear Information System (INIS)

    Buffet, J.

    1994-01-01

    The main benefit of electric cars is to reduce air pollution in cities that is thus desirable to equip them with non polluting air conditioning units and this rules out frigorific compressors operating with CFC. The planned replacement of CFC by HFC is at best an interim solution. The best solution is certainly to use thermoelectric air conditioning units, which are inherently pollution-free. However, these have a fairly low COPF when compared to traditional compressor units. We study the relationship between the cooling of the interior of urban electric cars and the merit factor of the thermoelectric material in their Peltier unit. This should help provide concrete target properties of future T E materials. copyright 1995 American Institute of Physics

  18. Articulated, Performance-Based Instruction Objectives Guide for Air Conditioning, Refrigeration, and Heating (Environmental Control System Installer/Servicer). Edition I.

    Science.gov (United States)

    Henderson, William Edward, Jr., Ed.

    This articulation guide contains 17 units of instruction for the first year of a two-year vocational program designed to prepare the high school graduate to install, maintain, and repair various types of residential and commercial heating, air conditioning, and refrigeration equipment. The units are to introduce the student to fundamental theories…

  19. Aspects of the design of the automated system for code generation of electrical items of technological equipment

    Directory of Open Access Journals (Sweden)

    Erokhin V.V.

    2017-09-01

    Full Text Available The article presents the aspects of designing an automated system for generating codes for electrical elements of process equipment using CASE-means. We propose our own technology of iterative development of such systems. The proposed methodology uses the tool to develop the ERwin Data Modeler databases of Computer Associates and the author's tool for the automatic generation of ERwin Class Builder code. The implemented design tool is a superstructure over the ERwin Data Modeler from Computer Associates, which extends its functionality. ERwin Data Modeler works with logical and physical data models and allows you to generate a description of the database and ddl-scripts.

  20. Monitoring equipment environment during nuclear plant operation at Salem and Hope Creek generating stations

    International Nuclear Information System (INIS)

    Blum, A.; Smith, R.J.

    1991-01-01

    Monitoring of environmental parameters has become a significant issue for operating nuclear power plants. While the long-term benefits of plant life extension programs are being pursued with comprehensive environmental monitoring programs, the potential effect of local hot spots at various plant locations needs to be evaluated for its effect on equipment degradation and shortening of equipment qualified life. A significant benefit can be experienced from temperature monitoring when a margin exists between the design versus actual operating temperature. This margin can be translated into longer equipment qualified life and significant reduction in maintenance activities. At PSE and G, the immediate need for monitoring environmental parameters is being accomplished via the use of a Logic Beach Bitlogger. The Bitlogger is a portable data loggings system consisting of a system base, input modules and a communication software package. Thermocouples are installed on selected electrical equipment and cables are run from the thermocouples to the input module of the Bitlogger. Temperature readings are taken at selected intervals, stored in memory, and downloaded periodically to a PC software program, i.e., Lotus. The data is formatted into tabular or graphical documents. Because of their versatility, Bitloggers are being used differently at the authors Nuclear facility. At the Salem Station (2 Units-4 loop Westinghouse PWR), a battery powered, fully portable, calibrated Bitlogger is located in an accessible area inside Containment where it monitors the temperature of various electrical equipment within the Pressurizer Enclosure. It is planned that close monitoring of the local hot spot temperatures in this area will allow them to adjust and reconcile the environmental qualification of the equipment

  1. Voltage controller design for air conditioning; Diseno de controlador de voltaje para aire acondicionado

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Andrade, R; Lopez Villalobos, J.J; Valderrama Chairez, J; Ramirez, R.L. [Instituto Tecnologico de Nuevo Leon, Guadalupe, Nuevo Leon (Mexico)]. E-mails: roxana_garciaandrade@yahoo.com; xe2n@yahoo.com.mx; jose.valderrama@ieee.org

    2013-03-15

    This paper discusses the design of a voltage controller for an air conditioning system in order to generate additional power in activation or startup of the system, for which as a first stage is presented the modeling power generation of electric current through alternative means, such as solar energy. The results of this study will be the basis for development of the physical prototype of this system controller. [Spanish] El presente trabajo trata sobre el diseno de un controlador de voltaje para un sistema de aire acondicionado con el fin de generar energia adicional en la activacion o arranque de dicho sistema, para lo cual como primer fase se presenta el modelado de la generacion de corriente electrica mediante medios alternos, como lo es la energia solar. Los resultados de este trabajo seran la base para desarrollo del prototipo fisico de este sistema controlador.

  2. Emergency systems and protection equipment of modular steam generators for fast reactors

    International Nuclear Information System (INIS)

    Matal, O.

    The requirements are discussed for accident protection of modular steam generators for fast reactors. Accident protection is assessed for a modular through-flow steam generator and for a natural circulation modular steam generator. Benefits and constraints are shown and possible improvements are outlined for accident protection of liquid sodium fired modular steam generators. (Kr)

  3. Designing the lithium bromide air conditioning absorption system for a bus

    International Nuclear Information System (INIS)

    Yusoff Ali; Kamaruzzaman Sopian; Hariadi

    2006-01-01

    A system of air-conditioning using Lithium Bromide absorption system is used as an alternative refrigerant that will not pollute the atmosphere. Lithium Bromide is a chemical salt soluble in water. There is a big difference between vapour compression system and LiBr 2 absorption system. The absorption air conditioning system is made of a generator, a condenser, an evaporator and an absorber with necessary pumps and piping. When LiBr 2 solution is heated under low pressure, water will evaporate first, while LiBr 2 will remain in the solution and will become more concentrated. The water is the refrigerant in this system. The generator, where the water is vapourised, is heated using an electric heater or solar energy. The LiBr 2 weak solution under low pressure in the generator is heated and the water evaporate into vapour. The vapour produced is then cooled in the condenser and then expanded into the evaporator. The refrigerant (water) in evaporator change phase from liquid to vapour by absorbing heat from cooling water, which flow in the coil in the evaporator. The chilled water obtained is then pumped into the fan coil, which will be used in conditioning the passenger area of the bus. The water vapour from the evaporator is absorbed into LiBr 2 solution in the absorber, forming a weak solution of LiBr 2 . the weak solution from the absorber is then pumped back to the generator to regenerate. The absorption system does not use compressor, but requires pumps that need lower input power compared to that of a compressor. The system is considered as a new application for the bus. This will have great potential and will be environmentally friendly. The model in this study will be used for calculation of the cooling load for the bus

  4. Challenges of using air conditioning in an increasingly hot climate

    Science.gov (United States)

    Lundgren-Kownacki, Karin; Hornyanszky, Elisabeth Dalholm; Chu, Tuan Anh; Olsson, Johanna Alkan; Becker, Per

    2018-03-01

    At present, air conditioning (AC) is the most effective means for the cooling of indoor space. However, its increased global use is problematic for various reasons. This paper explores the challenges linked to increased AC use and discusses more sustainable alternatives. A literature review was conducted applying a transdisciplinary approach. It was further complemented by examples from cities in hot climates. To analyse the findings, an analytical framework was developed which considers four societal levels—individual, community, city, and national. The main challenges identified from the literature review are as follows: environmental, organisational, socio-economical, biophysical and behavioural. The paper also identifies several measures that could be taken to reduce the fast growth of AC use. However, due to the complex nature of the problem, there is no single solution to provide sustainable cooling. Alternative solutions were categorised in three broad categories: climate-sensitive urban planning and building design, alternative cooling technologies, and climate-sensitive attitudes and behaviour. The main findings concern the problems arising from leaving the responsibility to come up with cooling solutions entirely to the individual, and how different societal levels can work towards more sustainable cooling options. It is concluded that there is a need for a more holistic view both when it comes to combining various solutions as well as involving various levels in society.

  5. Energy Analysis for Air Conditioning System Using Fuzzy Logic Control

    Directory of Open Access Journals (Sweden)

    Henry Nasution

    2011-04-01

    Full Text Available Reducing energy consumption and to ensure thermal comfort are two important considerations for the designing an air conditioning system. An alternative approach to reduce energy consumption proposed in this study is to use a variable speed compressor. The control strategy will be proposed using the fuzzy logic controller (FLC. FLC was developed to imitate the performance of human expert operators by encoding their knowledge in the form of linguistic rules. The system is installed on a thermal environmental room with a data acquisition system to monitor the temperature of the room, coefficient of performance (COP, energy consumption and energy saving. The measurements taken during the two hour experimental periods at 5-minutes interval times for temperature setpoints of 20oC, 22oC and 24oC with internal heat loads 0, 500, 700 and 1000 W. The experimental results indicate that the proposed technique can save energy in comparison with On/Off and proportional-integral-derivative (PID control.

  6. Thermoeconomic evaluation of air conditioning system with chilled water storage

    International Nuclear Information System (INIS)

    Lin, Hu; Li, Xin-hong; Cheng, Peng-sheng; Xu, Bu-gong

    2014-01-01

    Highlights: • A new thermoeconomic evaluation methodology has been presented. • The relationship between thermodynamic and economic performances has been revealed. • A key point for thermal storage technology further application is discovered. • A system has been analyzed via the new method and EUD method. - Abstract: As a good load shifting technology for power grid, chilled energy storage has been paid more and more attention, but it always consumes more energy than traditional air conditioning system, and the performance analysis is mostly from the viewpoint of peak-valley power price to get cost saving. The paper presents a thermoeconomic evaluation methodology for the system with chilled energy storage, by which thermodynamic performance influence on cost saving has been revealed. And a system with chilled storage has been analyzed, which can save more than 15% of power cost with no energy consumption increment, and just certain difference between peak and valley power prices can make the technology for good economic application. The results show that difference between peak and valley power prices is not the only factor on economic performance, thermodynamic performance of the storage system is the more important factor, and too big price difference is a barrier for its application, instead of for more cost saving. All of these give a new direction for thermal storage technology application

  7. Performance of alternative refrigerants for residential air-conditioning applications

    International Nuclear Information System (INIS)

    Park, Ki-Jung; Seo, Taebeom; Jung, Dongsoo

    2007-01-01

    In this study, performances of two pure hydrocarbons and seven mixtures composed of propylene, propane, HFC152a, and dimethylether were measured to substitute for HCFC22 in residential air-conditioners and heat pumps. Thermodynamic cycle analysis was carried out to determine the optimum compositions before testing and actual tests were performed in a breadboard-type laboratory heat pump/air-conditioner at the evaporation and condensation temperatures of 7 and 45 deg. C, respectively. Test results show that the coefficient of performance of these mixtures is up to 5.7% higher than that of HCFC22. While propane showed a 11.5% reduction in capacity, most of the fluids had a similar capacity to that of HCFC22. For these fluids, compressor-discharge temperatures were reduced by 11-17 deg. C. For all fluids tested, the amount of charge was reduced by up to 55% as compared to HCFC22. Overall, these fluids provide good performances with reasonable energy-savings without any environmental problem and thus can be used as long-term alternatives for residential air-conditioning and heat-pumping applications

  8. Hollow Fiber Membrane Dehumidification Device for Air Conditioning System.

    Science.gov (United States)

    Zhao, Baiwang; Peng, Na; Liang, Canzeng; Yong, Wai Fen; Chung, Tai-Shung

    2015-11-16

    In order to provide a comfortable living and working environment indoors in tropical countries, the outdoor air often needs to be cooled and dehumidified before it enters the rooms. Membrane separation is an emerging technology for air dehumidification and it is based on the solution diffusion mechanism. Water molecules are preferentially permeating through the membranes due to its smaller kinetic diameter and higher condensability than the other gases. Compared to other dehumidification technologies such as direct cooling or desiccation, there is no phase transition involved in membrane dehumidification, neither the contact between the fresh air stream and the desiccants. Hence, membrane dehumidification would not only require less energy consumption but also avoid cross-contamination problems. A pilot scale air dehumidification system is built in this study which comprises nine pieces of one-inch PAN/PDMS hollow fiber membrane modules. A 150 h long-term test shows that the membrane modules has good water vapor transport properties by using a low vacuum force of only 0.78 bar absolute pressure at the lumen side. The water vapor concentration of the feed humid air decreases dramatically from a range of 18-22 g/m³ to a range of 13.5-18.3 g/m³. Most importantly, the total energy saving is up to 26.2% compared with the conventional air conditioning process.

  9. Hollow Fiber Membrane Dehumidification Device for Air Conditioning System

    Directory of Open Access Journals (Sweden)

    Baiwang Zhao

    2015-11-01

    Full Text Available In order to provide a comfortable living and working environment indoors in tropical countries, the outdoor air often needs to be cooled and dehumidified before it enters the rooms. Membrane separation is an emerging technology for air dehumidification and it is based on the solution diffusion mechanism. Water molecules are preferentially permeating through the membranes due to its smaller kinetic diameter and higher condensability than the other gases. Compared to other dehumidification technologies such as direct cooling or desiccation, there is no phase transition involved in membrane dehumidification, neither the contact between the fresh air stream and the desiccants. Hence, membrane dehumidification would not only require less energy consumption but also avoid cross-contamination problems. A pilot scale air dehumidification system is built in this study which comprises nine pieces of one-inch PAN/PDMS hollow fiber membrane modules. A 150 h long-term test shows that the membrane modules has good water vapor transport properties by using a low vacuum force of only 0.78 bar absolute pressure at the lumen side. The water vapor concentration of the feed humid air decreases dramatically from a range of 18–22 g/m3 to a range of 13.5–18.3 g/m3. Most importantly, the total energy saving is up to 26.2% compared with the conventional air conditioning process.

  10. Central air conditioning based on adsorption and solar energy

    International Nuclear Information System (INIS)

    Pralon Ferreira Leite, Antonio; Belo, Francisco Antonio; Martins, Moacir Machado; Bressan Riffel, Douglas

    2011-01-01

    This paper presents the characterization and the pre-dimensioning of an adsorption chiller as part of a 20 kW air conditioning central unit for cooling a set of rooms that comprises an area of 110 m 2 . The system is basically made up of a cold water storage tank supplied by an activated carbon-methanol adsorption chiller, a hot water storage tank, fed by solar energy and natural gas, and a fan-coil. During an acclimatization of 8 h (9-17 h), the following parameters were obtained for dimensioning the cooling system: 504 kg of activated carbon, 180 L of methanol, 7000 L of hot water, 10,300 L of cold water with its temperature varying in the fan-coil from 1 deg. C to 14 C. Considering the mean value of the total daily irradiation in Joao Pessoa (7 o 8'S, 34 o 50'WG), and a cover of regenerating heat supplied by solar energy equivalent to 70%, the adsorption chiller's expected coefficient of performance (COP) was found to be around 0.6.

  11. Heat pipe heat exchanger for heat recovery in air conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Abd El-Baky, Mostafa A.; Mohamed, Mousa M. [Mechanical Power Engineering Department, Faculty of Engineering, Minufiya University, Shebin El-Kom (Egypt)

    2007-03-15

    The heat pipe heat exchangers are used in heat recovery applications to cool the incoming fresh air in air conditioning applications. Two streams of fresh and return air have been connected with heat pipe heat exchanger to investigate the thermal performance and effectiveness of heat recovery system. Ratios of mass flow rate between return and fresh air of 1, 1.5 and 2.3 have been adapted to validate the heat transfer and the temperature change of fresh air. Fresh air inlet temperature of 32-40{sup o}C has been controlled, while the inlet return air temperature is kept constant at about 26{sup o}C. The results showed that the temperature changes of fresh and return air are increased with the increase of inlet temperature of fresh air. The effectiveness and heat transfer for both evaporator and condenser sections are also increased to about 48%, when the inlet fresh air temperature is increased to 40{sup o}C. The effect of mass flow rate ratio on effectiveness is positive for evaporator side and negative for condenser side. The enthalpy ratio between the heat recovery and conventional air mixing is increased to about 85% with increasing fresh air inlet temperature. The optimum effectiveness of heat pipe heat exchanger is estimated and compared with the present experimental data. The results showed that the effectiveness is close to the optimum effectiveness at fresh air inlet temperature near the fluid operating temperature of heat pipes. (author)

  12. Research on Heat Exchange Process in Aircraft Air Conditioning System

    Science.gov (United States)

    Chichindaev, A. V.

    2017-11-01

    Using of heat-exchanger-condenser in the air conditioning system of the airplane Tu-204 (Boeing, Airbus, Superjet 100, MS-21, etc.) for cooling the compressed air by the cold air with negative temperature exiting the turbine results in a number of operational problems. Mainly it’s frosting of the heat exchange surface, which is the cause of live-section channels frosting, resistance increasing and airflow in the system decreasing. The purpose of this work is to analyse the known freeze-up-fighting methods for heat-exchanger-condenser, description of the features of anti-icing protection and offering solutions to this problem. For the problem of optimizing the design of heat exchangers in this work used generalized criterion that describes the ratio of thermal resistances of cold and hot sections, which include: the ratio of the initial values of heat transfer agents flow state; heat exchange surface finning coefficients; factors which describes the ratio of operating parameters and finning area. By controlling the ratio of the thermal resistances can be obtained the desired temperature of the heat exchange surface, which would prevent freezing. The work presents the results of a numerical study of the effect of different combinations of regime and geometrical factors changes on reduction of the heat-exchanger-condenser freezing surface area, including using of variable ratio of thermal resistances.

  13. A device for reduction of metal oxides generated in electrokinetic separation equipment

    International Nuclear Information System (INIS)

    Kim, Gye-Nam; Kim, Seung-Soo; Kim, Il-Gook; Jeong, Jung-Whan; Choi, Jong-Won

    2015-01-01

    For a reduction of waste electrolyte volume and metal oxide volume, the reuse period of the waste electrolyte in the electrokinetic decontamination experiment and the method of a reduction of metal oxide volume in the cathode chamber were drawn out through several experiments with the manufactured 1.2 ton electrokinetic decontamination equipment. The optimum pH of electrolyte in cathode chamber for a reduction of volume of metal oxides was below 2.35. Indoor electrokinetic decontamination equipment for treatment of 1.2 tons of the contaminated soil per batch was manufactured to remove uranium from soil with high removal efficiency during a short time. For a reduction of waste electrolyte volume and metal oxide volume, the reuse period of waste electrolyte in the electrokinetic decontamination experiment and the method of a reduction of metal oxide volume in the cathode chamber were drawn out through several experiments with the manufactured electrokinetic equipment. Indoor electrokinetic decontamination equipment for treatment of 1.2 tons of the contaminated soil was manufactured to remove uranium from soil during a short time

  14. A device for reduction of metal oxides generated in electrokinetic separation equipment

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Gye-Nam; Kim, Seung-Soo; Kim, Il-Gook; Jeong, Jung-Whan; Choi, Jong-Won [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    For a reduction of waste electrolyte volume and metal oxide volume, the reuse period of the waste electrolyte in the electrokinetic decontamination experiment and the method of a reduction of metal oxide volume in the cathode chamber were drawn out through several experiments with the manufactured 1.2 ton electrokinetic decontamination equipment. The optimum pH of electrolyte in cathode chamber for a reduction of volume of metal oxides was below 2.35. Indoor electrokinetic decontamination equipment for treatment of 1.2 tons of the contaminated soil per batch was manufactured to remove uranium from soil with high removal efficiency during a short time. For a reduction of waste electrolyte volume and metal oxide volume, the reuse period of waste electrolyte in the electrokinetic decontamination experiment and the method of a reduction of metal oxide volume in the cathode chamber were drawn out through several experiments with the manufactured electrokinetic equipment. Indoor electrokinetic decontamination equipment for treatment of 1.2 tons of the contaminated soil was manufactured to remove uranium from soil during a short time.

  15. Using PHM to measure equipment usable life on the Air Force's next generation reusable space booster

    Science.gov (United States)

    Blasdel, A.

    The U.S. Air Force procures many launch vehicles and launch vehicle services to place their satellites at their desired location in space. The equipment on-board these satellite and launch vehicle often suffer from premature failures that result in the total loss of the satellite or a shortened mission life sometimes requiring the purchase of a replacement satellite and launch vehicle. The Air Force uses its EELV to launch its high priority satellites. Due to a rise in the cost of purchasing a launch using the Air Force's EELV from 72M in 1997 to as high as 475M per launch today, the Air Force is working to replace the EELV with a reusable space booster (RSB). The RSB will be similar in design and operations to the recently cancelled NASA reusable space booster known as the Space Shuttle. If the Air Force uses the same process that procures the EELV and other launch vehicles and satellites, the RSB will also suffer from premature equipment failures thus putting the payloads at a similar high risk of mission failure. The RSB is expected to lower each launch cost by 50% compared to the EELV. The development of the RSB offers the Air Force an opportunity to use a new reliability paradigm that includes a prognostic and health management program and a condition-based maintenance program. These both require using intelligent, decision making self-prognostic equipment The prognostic and health management program and its condition-based maintenance program allows increases in RSB equipment usable life, lower logistics and maintenance costs, while increasing safety and mission assurance. The PHM removes many decisions from personnel that, in the past resulted in catastrophic failures and loss of life. Adding intelligent, decision-making self-prognostic equipment to the RSB will further decrease launch costs while decreasing risk and increasing safety and mission assurance.

  16. Full amenities : the jungle hums with armed guards, planned movements, air-conditioning and cultural realness

    Energy Technology Data Exchange (ETDEWEB)

    Leslie, J.

    2001-06-04

    The working situation of a Canadian consultant asked to work in Ecuador for a one-month period was described. He quickly learned that discretion is an incredibly valuable trait in this country where a number of oil and gas workers have become victims of kidnappings, because the companies that employ them are perceived as having lots of money. Accordingly, the planning for the trip began back in Canada where the worker received inoculations for yellow fever and hepatitis, among others, as well as briefing about personal security while abroad. Upon his arrival, he was met by security guards hired by the company and driven to his hotel in the capital, Quito. He found he was safe to wander inside the hotel at will, as well as just outside. If he wanted to go outside the perimeter, he had to call the company and the guards would meet and escort him, without displaying their weapons. When it came time to travel to the production site deep in the jungle, armed guards were travelling in a vehicle ahead of his, as well as in two vehicles behind him with weapons in full view. All of his movements were planned. The facilities on-site were more than adequate and resembled those found in Canada: flush toilet, air-conditioned sleeping quarters and cafeteria-style food. With air-conditioning available in buildings and in vehicles, it was not too difficult to adjust to the 40 Celsius heat, but one had to be equipped with very dark sunglasses. The high humidity and the heat made it different from conditions experienced in Canada. The people from Ecuador were very friendly and proud to be working on the rigs. Jobs are scarce and the level of poverty high. It was an enjoyable experience overall, as long as one is careful to mitigate risks and take the advice of experts. 3 figs.

  17. Ventilation and air conditioning systems in maritime productions units; Panorama dos sistemas de VAC em unidades maritimas de producao

    Energy Technology Data Exchange (ETDEWEB)

    Guedes, Fernando Pedrosa; Sztajnbok, Ernani Luis [PETROBRAS, Rio de Janeiro, RJ (Brazil); Padua, Carlos Eduardo Dantas de; Passos, Alfredo Silveira [DUOVAC Engenharia Ltda. (Brazil)

    2004-07-01

    In an Offshore Stationary Production Unit (SPU), the adequate project of the Ventilation and Air Conditioning (VAC) System is not only a thermal comfort requirement but part of the essential safety services of the installation and complement for area classification requirements associated with electrical equipment. The VAC installations are sometimes the object of complaints by onboard team. Problems such as unsatisfactory system performance, high noise levels in the accommodation quarters, offices and other areas and the discomfort caused by unbalanced ventilation and air conditioning systems, are some of the most frequent complaints. Air Conditioning systems are classified as Direct and Indirect Expansion. Decentralized systems with Indirect Expansion has been adopted in PETROBRAS projects. This conception is not used in VAC Systems for platforms installed in North Sea, where the use of Centralized Systems with Direct Expansion are more common. The objective of this work is to compare the VAC conception projects, analyzing their advantages and disadvantages . The evaluation of VAC System in PETROBRAS project, and their steps in SPU development, is also scope of this paper. (author)

  18. Optimal design of wind power generation equipment%风力发电设备的优化设计

    Institute of Scientific and Technical Information of China (English)

    宗倩

    2016-01-01

    风能清洁无污染,是人们梦寐以求的新能源。风力发电是一种有效利用风能的新形式,风力发电设备决定着发电效率与发电成本,因此优化发电设备至关重要。通过阐述风力发电基本原理及现代风机的基本组成,提出风力发电设备优化设计的几点思路,为提高风力发电可利用价值提供参考。%Wind power is clean and pollution-free, which is the new energy people want to use. Wind power generation is aneffectivenewformofusingwindenergy,windpowergenerationequipmentdeterminestheefficiencyandcostofpower generation, therefore to optimize power generation equipment is essential. Through elaborating basic composition of wind power generation and basic principles of modern wind turbines, this paper proposed a few ideas on optimal design of wind power generation equipment, which provided reference for increasing its use value.

  19. Energy Savings Potential and Research, Development, & Demonstration Opportunities for Residential Building Heating, Ventilation, and Air Conditioning Systems

    Energy Technology Data Exchange (ETDEWEB)

    Goetzler, William [Navigant Consulting, Inc., Burlington, MA (United States); Zogg, Robert [Navigant Consulting, Inc., Burlington, MA (United States); Young, Jim [Navigant Consulting, Inc., Burlington, MA (United States); Schmidt, Justin [Navigant Consulting, Inc., Burlington, MA (United States)

    2012-10-01

    This report is an assessment of 135 different heating, ventilation, and air-conditioning (HVAC) technologies for U.S. residential buildings to identify and provide analysis on 19 priority technology options in various stages of development. The analyses include an estimation of technical energy-savings potential, descriptions of technical maturity, descriptions of non-energy benefits, descriptions of current barriers for market adoption, and descriptions of the technology's applicability to different building or HVAC equipment types. From these technology descriptions, are suggestions for potential research, development and demonstration (RD&D) initiatives that would support further development of the priority technology options.

  20. Energy Savings Potential and Research, Development, & Demonstration Opportunities for Commercial Building Heating, Ventilation, and Air Conditioning Systems

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2011-09-01

    This report covers an assessment of 182 different heating, ventilation, and air-conditioning (HVAC) technologies for U.S. commercial buildings to identify and provide analysis on 17 priority technology options in various stages of development. The analyses include an estimation of technical energy-savings potential, description of technical maturity, description of non-energy benefits, description of current barriers for market adoption, and description of the technology’s applicability to different building or HVAC equipment types. From these technology descriptions, are suggestions for potential research, development and demonstration (RD&D) initiatives that would support further development of the priority technology options.

  1. Sphingomonas frigidaeris sp. nov., isolated from an air conditioning system.

    Science.gov (United States)

    Lee, Yunho; Jeon, Che Ok

    2017-10-01

    A strictly aerobic Gram-stain-negative bacterium, designated strain KER25-10 T , was isolated from a laboratory air conditioning system in South Korea. Cells were yellow-pigmented, non-motile rods showing catalase- and oxidase-positive reactions. The strain grew at pH 4.0-9.0 (optimum, pH 6.0-7.0) and 10-40 °C (optimum, 30 °C) and in the presence of 0-3 % (w/v) NaCl (optimum, 0 %). The G+C content of the genomic DNA was 65.1 mol%. Strain KER25-10 T contained ubiquinone-10 (Q-10) as the predominant isoprenoid quinone and C16 : 0, C17 : 1ω6c, summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c) and summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c) as the major fatty acids. The major polar lipids were sphingoglycolipid, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and phosphatidylcholine. Only spermidine was detected as the polyamine. Phylogenetic analysis based on 16S rRNA sequences indicated that strain KER25-10 T formed a distinct phylogenetic lineage within the genus Sphingomonas of the family Sphingomonadaceae and the strain was most closely related to Sphingomonas kyeonggiense THG-DT81 T with a 96.8 % 16S rRNA gene sequence similarity. On the basis of phenotypic, chemotaxonomic and molecular features, strain KER25-10 T clearly represents a novel species of the genus Sphingomonas, for which the name Sphingomonas frigidaeris sp. nov. is proposed. The type strain is KER25-10 T (=KACC 19285 T =JCM 32053 T ).

  2. Mapping of iso exposure curves generated by conventional mobile radiodiagnostic equipment and dose in hospitalized patients

    International Nuclear Information System (INIS)

    Hoff, Gabriela; Fischer, Andreia Caroline Fischer da Silveira; Accurso, Andre; Andrade, Jose Rodrigo Mendes; Bacelar, Alexandre

    2011-01-01

    This paper intended to measure iso expositions curves in areas of mobile equipment use. It was selected: a Shimadzu mobile equipment and two Siemens equipment, being used a non-anthropomorphic scatterer. The exposure measurements in mesh of 4.20 x 4.20 cubic centimeters, at a half-height of the simulator and steps of 30 cm, were used by using the radiographic techniques: 100 k Vp and 63 m As (Shimadzu) and 96 k Vp and 40 m As (Siemens). For estimation of environmental equivalent dose, during 12 months, were considered: 3.55 m As/examination and 44.5 procedures/month (adults): and 3.16 m As/examination and 20.1 procedures/month (pediatrics). It was observed that only the values in the distance of 60 cm presented over the maximum limit of environment equivalent dose defined for Free Area (0.5 mSv/year). The points collected at 2.1 m from the primary beam center, have shown to be always 12% of referred limit, shown to be a safe distance for the hospitalized patients

  3. The new generation of detection and identification equipment; Nouvelle generation de materiel de detection et d' identification

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, F.; Guerin, M.; Fort, Ph. [Mirion technologies, division HPH, BPI - 13113 Lamanon (France)

    2009-07-01

    The authors address the highly sensitive detection issue with real time identification of the risk nature, a problem which occurs every time a source is only fleetingly present (a pedestrian, a vehicle or an object on a conveyor belt passing by). They briefly present a range of instruments specially designed for this purpose, the SPIR-Ident instruments. These equipment use one or several large sensors, digital multichannel analyzers (one per sensor) and neutron and gamma measurements. Spectra are continuously processed, stabilized, linearized and normalized, and finally analyzed by an algorithm. The authors evoke the performance characterization and a return on experience after a 6 month-use for the control of passengers and luggage in airport

  4. EMI environment EMC considerations concerning equipment upgrades at a nuclear utility power generating station a case history

    International Nuclear Information System (INIS)

    Metcalf, M.J.

    1993-01-01

    As equipment is upgraded during scheduled power outages in nuclear power generating stations, more and more utilities will be faced with the problem of dealing with Electromagnetic Compatibility (EMC) issues that have evolved with the trend of manufacturers designing equipment based around state-of-the-art high technology logic devices. This paper lists Commonwealth Edison Company (CECO) equipment that was scrutinized by National Technical Systems (NTS) for its EMI impact. The test requirements and test procedures for assessing EMI and EMC are outlined. Although on-site mapping data was gathered to assist CECO for the upgrade described here of the Auxiliary Electric Equipment Room of a Westinghouse Eagle 21 Reactor Protection System at the Zion Unit No.1 Station, blanket mapping of every location for every upgrade is a short term, expensive solution to the EMI problem. It is concluded that the primary problem of lack of system and component level EMI specifications must be addressed by a governing body. 7 refs., 2 figs

  5. Air conditioning systems as non-infectious health hazards inducing acute respiratory symptoms.

    Science.gov (United States)

    Gerber, Alexander; Fischer, Axel; Willig, Karl-Heinz; Groneberg, David A

    2006-04-01

    Chronic and acute exposure to toxic aerosols belongs to frequent causes of airway diseases. However, asthma attacks due to long-distance inhalative exposure to organic solvents, transmitted via an air condition system, have not been reported so far. The present case illustrates the possibility of air conditioning systems as non-infectious health hazards in occupational medicine. So far, only infectious diseases such as legionella pneumophila pneumonia have commonly been associated to air-conditioning exposures but physicians should be alert to the potential of transmission of toxic volatile substances via air conditioning systems. In view of the events of the 11th of September 2001 with a growing danger of large building terrorism which may even use air conditioning systems to transmit toxins, facility management security staff should be alerted to possible non-infectious toxic health hazards arising from air-conditioning systems.

  6. Modeling and Maximum Power Point Tracking Control of Wind Generating Units Equipped with Permanent Magnet Synchronous Generators in Presence of Losses

    Directory of Open Access Journals (Sweden)

    Andrea Bonfiglio

    2017-01-01

    Full Text Available This paper focuses on the modeling of wind turbines equipped with direct drive permanent magnet synchronous generators for fundamental frequency power system simulations. Specifically, a procedure accounting for the system active power losses to initialize the simulation starting from the load flow results is proposed. Moreover, some analytical assessments are detailed on typical control schemes for fully rated wind turbine generators, thereby highlighting how active power losses play a fundamental role in the effectiveness of the wind generator control algorithm. Finally, the paper proposes analytical criteria to design the structure and the parameters of the regulators of the wind generator control scheme. Simulations performed with Digsilent Power Factory validated the proposed procedure, highlighting the impact of active power losses on the characterization of the initial steady state and that the simplifying assumptions done in order to synthesize the controllers are consistent with the complete modeling performed by the aforementioned power system simulator.

  7. Thermal design of a modern, air-conditioned, single-floor, solar-powered desert house

    KAUST Repository

    Serag-Eldin, M. A.

    2011-12-01

    The paper presents a thermal analysis of a single-floor, solar-powered desert house. The house is air-conditioned and provides all modern comforts and facilities. Electrical power, which drives the entire energy system, is generated by roof-mounted photovoltaic modules. The modules are fixed on special cradles which fold at night to expose the roof to the night sky, thereby enhancing night-time cooling, which is substantial in the desert environment. A detailed dynamic heat transfer analysis is conducted for the building envelope, coupled with a solar radiation model. Application to a typical Middle-Eastern desert site reveals that indeed such a design is feasible with present-day technology; and should be even more attractive with future advances in technology. © 2011 Copyright Taylor and Francis Group, LLC.

  8. Influence of Urban Microclimate on Air-Conditioning Energy Needs and Indoor Thermal Comfort in Houses

    Directory of Open Access Journals (Sweden)

    Feng-Chi Liao

    2015-01-01

    Full Text Available A long-term climate measurement was implemented in the third largest city of Taiwan, for the check of accuracy of morphing approach on generating the hourly data of urban local climate. Based on observed and morphed meteorological data, building energy simulation software EnergyPlus was used to simulate the cooling energy consumption of an air-conditioned typical flat and the thermal comfort level of a naturally ventilated typical flat. The simulated results were used to quantitatively discuss the effect of urban microclimate on the energy consumption as well as thermal comfort of residential buildings. The findings of this study can serve as a reference for city planning and energy management divisions to study urban sustainability strategies in the future.

  9. Open absorption system for cooling and air conditioning using membrane contactors. 2006 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Conde-Petit, M. [M. Conde Engineering, Zuerich (Switzerland); Weber, R. [Materials Science and Technology (EMPA), Abteilung Bautechnologien, Duebendorf (Switzerland)

    2006-11-15

    This illustrated annual report for 2006 for the Swiss Federal Office of Energy (SFOE) reports on work being done on the development of an open absorption system for cooling and air-conditioning. The report reviews the construction of a first prototype and the manufacture of its components. The conceptual design of this new type of air handling unit (AHU), operating with a liquid desiccant, is discussed. The AHU is to be autonomous and the system will not require additional mechanical refrigeration. It is to be thermally driven at temperatures below 80 {sup o}C. Waste heat sources, solar collectors, district heating plants and co-generation systems are targeted as providers of thermal energy at this temperature level. Work carried out is reported on, including that on two-stream membrane contactors.

  10. DESIGN OF WATER-COOLED PACKAGED AIR-CONDITIONING SYSTEMS BASED ON RELIABILITY ASSESSMENT

    OpenAIRE

    関口, 圭輔; 中尾, 正喜; 藁谷, 至誠; 植草, 常雄; 羽山, 広文

    2007-01-01

    Water-cooled packaged air-conditioning systems are reevaluated in terms of alleviating the heat island phenomenon in cities and effectively utilizing building rooftops. Up to now, such reliability assessment has been insufficient, and this has limited the use of this kind of air-conditioning system in the information and communications sectors that demand a high reliability. This work has led to the development of a model for evaluating the reliability of water-cooled package air-conditioning...

  11. Simulation of a MW rotor equipped with vortex generators using CFD and an actuator shape model

    DEFF Research Database (Denmark)

    Troldborg, Niels; Zahle, Frederik; Sørensen, Niels N.

    2015-01-01

    This article presents a comparison of CFD simulations of the DTU 10 MW reference wind turbine with and without vortex generators installed on the inboard part of the blades. The vortex generators are modelled by introducing body forces determined using a modified version of the so-called BAY mode...

  12. A study of energy use for ventilation and air-conditioning systems in Hong Kong

    Science.gov (United States)

    Yu, Chung Hoi Philip

    Most of the local modern buildings are high-rise with enclosed structure. Mechanical ventilation and air conditioning (MVAC) systems are installed for thermal comfort. Various types of MVAC systems found in Hong Kong were critically reviewed with comments on their characteristics in energy efficiency as well as application. The major design considerations were also discussed. Besides MVAC, other energy-consuming components in commercial buildings were also identified, such as lighting, lifts and escalators, office equipment, information technology facilities, etc. A practical approach has been adopted throughout this study in order that the end results will have pragmatic value to the heating, ventilating and air-conditioning (HVAC) industry in Hong Kong. Indoor Air Quality (IAQ) has become a major issue in commercial buildings worldwide including Hong Kong. Ventilation rate is no doubt a critical element in the design of HVAC systems, which can be realized more obviously in railway train compartments where the carbon dioxide level will be built up quickly when the compartments are crowded during rush hours. A study was carried out based on a simplified model using a train compartment that is equipped with an MVAC system. Overall Thermal Transfer Value (OTTV) is a single-value parameter for controlling building energy use and is relatively simple to implement legislatively. The local government has taken a first step in reacting to the worldwide concern of energy conservation and environmental protection since 1995. Different methods of OTTV calculation were studied and the computation results were compared. It gives a clear picture of the advantages and limitations for each method to the building designers. However, due to the limitations of using OTTV as the only parameter for building energy control, some new approaches to a total control of building energy use were discussed and they might be considered for future revision of the building energy codes in Hong

  13. Methylobacterium frigidaeris sp. nov., isolated from an air conditioning system.

    Science.gov (United States)

    Lee, Yunho; Jeon, Che Ok

    2018-01-01

    A reddish pink-pigmented, Gram-stain-negative, aerobic and methylotrophic bacterial strain, designated strain IER25-16 T , was isolated from a laboratory air conditioning system in the Republic of Korea. Cells were motile rods showing catalase- and oxidase-positive reactions. Strain IER25-16 T grew at 10-40 °C (optimum, 30 °C), at pH 4.0-7.0 (optimum, pH 5.0-7.0) and in the presence of 0-1.0 % (w/v) NaCl (optimum, 0 %). The major respiratory quinone was ubiquinone-10 and ubiquinone-9 was also detected as the minor respiratory quinone. Summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c) was detected as the predominant fatty acids. The genomic DNA G+C content of strain IER25-16 T was 70.0 mol%. Phylogenetic analysis based on 16S rRNA gene sequence comparison revealed that strain IER25-16 T belonged to the genus Methylobacterium of the class Alphaproteobacteria. Strain IER25-16 T was most closely related to Methylobacterium platani PMB02 T (97.9 %), Methylobacterium aquaticum GR16 T (97.9 %) and Methylobacterium tarhaniae N4211 T (97.5 %). The average nucleotide identity and in silico DNA-DNA hybridization values between strain IER25-16 T and M. platani, M. aquaticum and M. tarhaniae were 88.3, 88.8 and 89.6 % and 36.2, 37.3 and 39.3 %, respectively. The phenotypic and chemotaxonomic features and the phylogenetic inference clearly suggested that strain IER25-16 T represents a novel species of the genus Methylobacterium, for which the name Methylobacteriumfrigidaeris sp. nov. is proposed. The type strain is strain IER25-16 T (=KACC 19280 T =JCM 32048 T ).

  14. Design of segmental ultrasonic cleaning equipment for removing the sludge in a steam generator

    International Nuclear Information System (INIS)

    Kim, Seok Tae; Jeong, Woo Tae; Byeon, Min Suk; Lee, Ho One

    2010-01-01

    In nuclear power plants, the water in the coolant system is managed to be clean but metallic sludge is accumulated on the top of tube-sheet in a steam generator. The sludge causes the corrosion of the tubesheet. The electric utility company in Korea removes the sludge with a lancing system for every outage of nuclear power plants. But the sludge is not perfectly removed with lancing system because the pressurized water of the lancing system cannot reach all area in a steam generator. Therefore the steam generator cleaning system with ultrasonic energy has been developed in KEPCO Research Institute. In this paper, the ultrasonic cleaning system is designed for removing the sludge on the steam generator

  15. Development and planning and design of equipment pumping generator of semiconductor lasers

    Science.gov (United States)

    Popkov, A. V.

    1974-01-01

    The schematic of a multidimensional current pulse generator is studied. A MTKh-90 cold cathode thyratron is used as the current commutator. In the autooscillation mode on a frequency of 380 hertz the generator creates a current to 100 amps per pulse in a control resistance of 1 ohm. The pulse duration is regulated within the limits from 0.1 to 3.0 microseconds.

  16. Impact of equipment failures and wind correlation on generation expansion planning

    DEFF Research Database (Denmark)

    Pineda, S.; Morales, J.M.; Ding, Y.

    2014-01-01

    the generating company (GENCO) and the system operator. The upper-level problem maximizes the GENCO's expected profit, while the lower-level problem simulates an hourly market-clearing procedure, through which LMPs are determined. The uncertainty pertaining to failures and wind power correlation is characterized......Generation expansion planning has become a complex problem within a deregulated electricity market environment due to all the uncertainties affecting the profitability of a given investment. Current expansion models usually overlook some of these uncertainties in order to reduce the computational...

  17. Natural convection liquid desiccant loop as an auxiliary air conditioning system: investigating the operational parameters

    Science.gov (United States)

    Fazilati, Mohammad Ali; Alemrajabi, Ali Akbar; Sedaghat, Ahmad

    2018-03-01

    Liquid desiccant air conditioning system with natural convection was presented previously as a new generation of AC systems. The system consists of two three-fluid energy exchangers namely absorber and regenerator in which the action of air dehumidifying and desiccant regeneration is done, respectively. The influence of working parameters on system performance including the heat source and heat sink temperature, concentration of desiccant solution fills the system initially and humidity content of inlet air to regenerator is investigated experimentally. The heat source temperatures of 50 °C and 60 °C, heat sink temperatures of 15 °C and 20 °C and desiccant concentrations of 30% and 34%, are examined here. The inlet air to regenerator has temperature of 38.5 °C and three relative humidity of 14%, 38% and 44%. In all experiments, the inlet air to absorber has temperature of 31 °C and relative humidity of 75%. By inspecting evaluation indexes of system, it is revealed that higher startup desiccant concentration solution is more beneficial for all study cases. It is also observed although the highest/lowest temperature heat source/heat sink is most suitable for best system operation, increasing the heat source temperature should be accompanied with decreasing heat sink temperature. Using drier air stream for regenerator inlet does not necessarily improve system performance; and the air stream with proper value of humidity content should be employed. Finally after running the system in its best working condition, the coefficient of performance (COP) reached 4.66 which verified to be higher than when the same air conditioning task done by a conventional vapor compression system, in which case the COP was 3.38.

  18. Feasibility study of using agriculture waste as desiccant for air conditioning system

    Energy Technology Data Exchange (ETDEWEB)

    Khedari, J.; Rawangkul, R.; Hirunlabh, J. [King Mongkut' s University of Technology Thonburi, Bangkok (Thailand). Buidling Scientific Research Center; Chimchavee, W. [University of Thai Chamber of Commerce, Bangkok (Thailand); Watanasungsuit, A. [South East Asia Univ., Bangkok (Thailand). Engineering Management

    2003-08-01

    This research was aimed at investigating the feasibility of using dried agricultural waste as desiccant for an open cycle air conditioning system. The natural fibers are, therefore, intended to replace chemical desiccant such as silica gel, molecular sieves etc. The investigation was limited to Coconut coir (Cocos nucifera) and Durian peels (Durio zibethinus). Experimental results confirmed that dry coconut coir and durian peel can absorb 30 g and 17 g H{sub 2}O per 100 g dry product, respectively, from air at the average condition of 32{sup o}C and 75% relative humidity. The optimum airflow rate is about 84 and 98 m{sup 3}/hr-100 g dry product, respectively. Therefore, the dry coconut coir is more suitable than the dry durian peel. Comparison between the dry coconut coir and silica gel showed that the average adsorption rate of coconut coir is less than that of silica gel by about 5 g/h-100 g dry product at an airflow rate of 84 m{sup 3}/h and 60 min operating time. However, it is still an interesting option to replace silica gel in open cycle air conditioning system, as the decrease of average adsorption rate is rather small. The other extremely interesting advantage of coconut coir is that during moisture absorption the heat generated during the process is less important. That means the air leaves the coconut coir bed at a lower temperature compared to that with a silica gel. Therefore, the saving of cooling energy is much more important. (Author)

  19. Convex modeling and optimization of a vehicle powertrain equipped with a generator-turbine throttle unit

    NARCIS (Netherlands)

    Marinkov, S.; Murgovski, N.; de Jager, A.G.

    2017-01-01

    This paper investigates an internal combustion (gasoline) engine throttled by a generator-turbine unit. Apart from throttling, the purpose of this device is to complement the operation of a conventional car alternator and support its downsizing by introducing an additional source of energy for the

  20. 2015 German refrigeration and air conditioning meeting. Abstracts; Deutsche Kaelte- und Klimatagung 2015. Kurzfassungen

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-07-01

    The volume contains the abstracts of the 2015 German refrigeration and air conditioning meeting in 5 chapters: cryo-technology, fundamentals of materials for refrigeration engineering and heat pump technology, facilities and components for the refrigeration and heat pump technology; application of refrigeration engineering; air conditioning technology and heat pump application.

  1. The Effect of Air-Conditioning on Student and Teacher Performance.

    Science.gov (United States)

    Phoenix Union High School District, AZ. Dept. of Research and Planning.

    The literature is reviewed to see if research shows a relationship between student and teacher performance and air conditioning of classrooms. The benefits of air conditioning in promoting learning are substantiated by studies that are summarized but not cited. The relationship of the report to the Phoenix Union High School System Advisory…

  2. An expert fault diagnosis system for vehicle air conditioning product development

    NARCIS (Netherlands)

    Tan, C.F.; Tee, B.T.; Khalil, S.N.; Chen, W.; Rauterberg, G.W.M.

    2015-01-01

    The paper describes the development of the vehicle air-conditioning fault diagnosis system in automotive industries with expert system shell. The main aim of the research is to diagnose the problem of new vehicle air-conditioning system development process and select the most suitable solution to

  3. The study of operating an air conditioning system using Maisotsenko-Cycle

    Science.gov (United States)

    Khan, Mohammad S.; Tahan, Sami; Toufic El-Achkar, Mohamad; Abou Jamus, Saleh

    2018-03-01

    The project aims to design and build an air conditioning system that runs on the Maisotsenko cycle. The system is required to condition and cool down ambient air for a small residential space with the reduction in the use of electricity and eliminating the use of commercial refrigerants. This project can operate at its optimum performance in remote areas like oil diggers and other projects that run in the desert or any site that would not have a very high relative humidity level. The Maisotsenko cycle is known as the thermodynamic concept that captures energy from the air by using the psychometric renewable energy available in the latent heat in water evaporating in air. The heat and mass exchanger design was based on choosing a material that would-be water resistant and breathable, which was found to be layers of cardboard placed on top of each other and thus creating channels for air to pass through. Aiming for this design eliminates any high power electrical equipment such as compressors, condensers and evaporators that would be used in an AC system with the exception of a 600 W blower and a 10 W fan, thus making it a more environmentally friendly project. Moreover, the project is limited by the ambient temperature and humidity, as the model operates at an optimum when the relative humidity is lower.

  4. Radon mitigation in schools utilising heating, ventilating and air conditioning systems

    International Nuclear Information System (INIS)

    Fisher, G.; Ligman, B.; Brennan, T.; Shaughnessy, R.; Turk, B.H.; Snead, B.

    1994-01-01

    As part of a continuing radon in schools technology development effort, EPA's School Evaluation Team has performed radon mitigation in schools by the method of ventilation/pressurisation control technology. Ventilation rates were increased, at a minimum, to meet the American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE) standard, Ventilation for Acceptable Indoor Air Quality (ASHRAE 62-1989). This paper presents the results and the preliminary evaluations which led to the team's decision to implement this technology. Factors considered include energy penalties, comfort, indoor air quality (IAQ), building shell tightness, and equipment costs. Cost benefit of heat recovery ventilation was also considered. Earlier results of the SEP team's efforts have indicated a severe ventilation problem within the schools of the United States. Two case studies are presented where HVAC technology was implemented for controlling radon concentrations. One involved the installation of a heat recovery ventilator to depressurise a crawl space and provide ventilation to the classrooms which previously had no mechanical ventilation. The other involved the restoration of a variable air volume system in a two-storey building. The HVAC system's controls were restored and modified to provide a constant building pressure differential to control the entry of radon. Pre-mitigation and post-mitigation indoor air pollutant measurements were taken, including radon, carbon dioxide (CO 2 ), particulates, and bio-aerosols. Long-term monitoring of radon, CO 2 , building pressure differentials, and indoor/outdoor temperature and relative humidity is presented. (author)

  5. Highlighting the harmonic regime generated by electric locomotives equipped with DC motors

    Science.gov (United States)

    Baciu, I.; Cunţan, C. D.

    2018-01-01

    The paper presents the results of measurements made using the C.A. 8334 power quality analyzer on an electric locomotive equipped with DC motors. We carried out determinations of the current-voltage regime using a locomotive motor. The harmonic regime of the other motors being identical to the analysed one, we could easily deduce the effects caused by the entire locomotive. The data measured with the analyzer were firstly transferred into a computer system using the Qualistar software, followed by data processing in Excel, enabling therefore a graphical representation of the characteristic parameters of power quality. Based on the acquired data, we determined the power factor, as well as the active, reactive and apparent power. The measurements revealed high values of the current harmonics, fact that required some measures to be taken for reducing the values of these harmonics. For this, we ran a simulation using the PSCAD/EMTDC software, by introducing LC filters in tune with the harmonic frequencies. The result was a significant reduction in the harmonic regime, either in the harmonics values or the power factor and reactive power.

  6. Opportunities to Reduce Air-Conditioning Loads Through Lower Cabin Soak Temperatures

    International Nuclear Information System (INIS)

    Farrington, R.; Cuddy, M.; Keyser, M.; Rugh, J.

    1999-01-01

    Air-conditioning loads can significantly reduce electric vehicle (EV) range and hybrid electric vehicle (HEV) fuel economy. In addition, a new U. S. emissions procedure, called the Supplemental Federal Test Procedure (SFTP), has provided the motivation for reducing the size of vehicle air-conditioning systems in the United States. The SFTP will measure tailpipe emissions with the air-conditioning system operating. If the size of the air-conditioning system is reduced, the cabin soak temperature must also be reduced, with no penalty in terms of passenger thermal comfort. This paper presents the impact of air-conditioning on EV range and HEV fuel economy, and compares the effectiveness of advanced glazing and cabin ventilation. Experimental and modeled results are presented

  7. Method of generating magnetoactive plasma for forming thin surface layers on solid substrates and equipment therefor

    International Nuclear Information System (INIS)

    Bardos, L.; Loncar, G.; Musil, J.; Zacek, F.

    1979-01-01

    The invention essentially consists in the use of the axially symmetrical high-frequency magnetized plasma column for thin layer formation. The plasma is generated using a cylindrical microwave slow-down structure in the outer magnetic field. Plasma particles density and temperature and their radial distribution are adjusted by changing the intensity of the magnetic field and of high-frequency power. The plasma may be generated from any gases in a pressure range of 10 -3 to 10 2 Pa. In an oxygen plasma, e.g., it is thus possible to form layers of 200 nm in thickness in 60 mins at an input high-frequency power of 100 to 300 W. (J.U.)

  8. Optimization and Performance Study of Select Heating Ventilation and Air Conditioning Technologies for Commercial Buildings

    Science.gov (United States)

    Kamal, Rajeev

    Buildings contribute a significant part to the electricity demand profile and peak demand for the electrical utilities. The addition of renewable energy generation adds additional variability and uncertainty to the power system. Demand side management in the buildings can help improve the demand profile for the utilities by shifting some of the demand from peak to off-peak times. Heating, ventilation and air-conditioning contribute around 45% to the overall demand of a building. This research studies two strategies for reducing the peak as well as shifting some demand from peak to off-peak periods in commercial buildings: 1. Use of gas heat pumps in place of electric heat pumps, and 2. Shifting demand for air conditioning from peak to off-peak by thermal energy storage in chilled water and ice. The first part of this study evaluates the field performance of gas engine-driven heat pumps (GEHP) tested in a commercial building in Florida. Four GEHP units of 8 Tons of Refrigeration (TR) capacity each providing air-conditioning to seven thermal zones in a commercial building, were instrumented for measuring their performance. The operation of these GEHPs was recorded for ten months, analyzed and compared with prior results reported in the literature. The instantaneous COPunit of these systems varied from 0.1 to 1.4 during typical summer week operation. The COP was low because the gas engines for the heat pumps were being used for loads that were much lower than design capacity which resulted in much lower efficiencies than expected. The performance of equivalent electric heat pump was simulated from a building energy model developed to mimic the measured building loads. An economic comparison of GEHPs and conventional electrical heat pumps was done based on the measured and simulated results. The average performance of the GEHP units was estimated to lie between those of EER-9.2 and EER-11.8 systems. The performance of GEHP systems suffers due to lower efficiency at

  9. Study of a thermoelectric system equipped with a maximum power point tracker for stand-alone electric generation.

    Science.gov (United States)

    Favarel, C.; Champier, D.; Bédécarrats, J. P.; Kousksou, T.; Strub, F.

    2012-06-01

    According to the International Energy Agency, 1.4 billion people are without electricity in the poorest countries and 2.5 billion people rely on biomass to meet their energy needs for cooking in developing countries. The use of cooking stoves equipped with small thermoelectric generator to provide electricity for basic needs (LED, cell phone and radio charging device) is probably a solution for houses far from the power grid. The cost of connecting every house with a landline is a lot higher than dropping thermoelectric generator in each house. Thermoelectric generators have very low efficiency but for isolated houses, they might become really competitive. Our laboratory works in collaboration with plane`te-bois (a non governmental organization) which has developed energy-efficient multifunction (cooking and hot water) stoves based on traditional stoves designs. A prototype of a thermoelectric generator (Bismuth Telluride) has been designed to convert a small part of the energy heating the sanitary water into electricity. This generator can produce up to 10 watts on an adapted load. Storing this energy in a battery is necessary as the cooking stove only works a few hours each day. As the working point of the stove varies a lot during the use it is also necessary to regulate the electrical power. An electric DC DC converter has been developed with a maximum power point tracker (MPPT) in order to have a good efficiency of the electronic part of the thermoelectric generator. The theoretical efficiency of the MMPT converter is discussed. First results obtained with a hot gas generator simulating the exhaust of the combustion chamber of a cooking stove are presented in the paper.

  10. P2000 - a new austenitic high nitrogen steel for power generating equipment

    International Nuclear Information System (INIS)

    Stein, G.; Hucklenbroich, I.; Wagner, M.

    1999-01-01

    For over 40 years most retaining rings worldwide were manufactured from austenitic materials which met visually all the demands made by designers. In these days two properties however fell short: resistance to stress corrosion cracking and in some cases strength. The operating conditions in normal environment caused in recent years problems with retaining rings which ended in some cases in down times and even generator destructions. Ultrasonic inspection in most cases is difficult, due to the complex geometry on the inside surface of the finish-machined and shrink-fitted retaining ring. In addition, the most highly stressed areas on the inside surface of the ring are inaccessible, unless the ring is removed from the rotor. Even then it is still very difficult, to find surface cracks, because they may have become very narrow, as a result of relaxation, or be concealed by corrosion products. The situation changed when our company in the late seventies developed a new material which could close these gaps. Due to the existing coil insulating material the max. operating temperature for generators was about 90 C. This was the reason why many utilities have changed the old retaining rings against the new corrosion resistant retaining rings made out of our material P900 or in some cases P900 N. (orig.)

  11. IEEE Std 1205-1993: IEEE guide for assessing, monitoring, and mitigating aging effects on Class 1E equipment used in nuclear power generating stations

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    The guidelines are provided for assessing, monitoring, and mitigating degradation of Class 1E equipment used in nuclear power generating stations due to aging. The methods described can be used to identify the performance capability of Class 1E equipment beyond its qualified life. A discussion of stressors and aging mechanisms is included. If aging considerations have been satisfactorily addressed through other means (e.g., equipment qualification), then use of this guide may not be warranted. For some equipment, only partial application of this guide may be warranted

  12. Methodology and measures for preventing unacceptable flow-accelerated corrosion thinning of pipelines and equipment of NPP power generating units

    Science.gov (United States)

    Tomarov, G. V.; Shipkov, A. A.; Lovchev, V. N.; Gutsev, D. F.

    2016-10-01

    Problems of metal flow-accelerated corrosion (FAC) in the pipelines and equipment of the condensate- feeding and wet-steam paths of NPP power-generating units (PGU) are examined. Goals, objectives, and main principles of the methodology for the implementation of an integrated program of AO Concern Rosenergoatom for the prevention of unacceptable FAC thinning and for increasing operational flow-accelerated corrosion resistance of NPP EaP are worded (further the Program). A role is determined and potentialities are shown for the use of Russian software packages in the evaluation and prediction of FAC rate upon solving practical problems for the timely detection of unacceptable FAC thinning in the elements of pipelines and equipment (EaP) of the secondary circuit of NPP PGU. Information is given concerning the structure, properties, and functions of the software systems for plant personnel support in the monitoring and planning of the inservice inspection of FAC thinning elements of pipelines and equipment of the secondary circuit of NPP PGUs, which are created and implemented at some Russian NPPs equipped with VVER-1000, VVER-440, and BN-600 reactors. It is noted that one of the most important practical results of software packages for supporting NPP personnel concerning the issue of flow-accelerated corrosion consists in revealing elements under a hazard of intense local FAC thinning. Examples are given for successful practice at some Russian NPP concerning the use of software systems for supporting the personnel in early detection of secondary-circuit pipeline elements with FAC thinning close to an unacceptable level. Intermediate results of working on the Program are presented and new tasks set in 2012 as a part of the updated program are denoted. The prospects of the developed methods and tools in the scope of the Program measures at the stages of design and construction of NPP PGU are discussed. The main directions of the work on solving the problems of flow

  13. IEEE No. 323, IEEE trial-use standard: General guide for qualifying Class I electric equipment for nuclear power generating stations

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This document describes the basic requirements for the qualification of Class I electric equipment. This is equipment which is essential to the safe shutdown and isolation of the reactor or whose failure or damage could result in significant release of radioactive material. The purpose of this document is to provide guidance for demonstrating the qualifications of electrical equipment as required in the IEEE Std 279 -- Criteria for Nuclear Power Generating Station Protection Systems, and IEEE Std 308 -- Criteria for Class 1E Electric Systems for Nuclear Power Generating Stations. The qualification methods described may be used in conjunction with the Guides for qualifying specific types of equipment, (see Foreword), for updating qualification following modifications or for qualifying equipment for which no applicable Guide exists

  14. Thermodynamic analysis of the two-phase ejector air-conditioning system for buses

    International Nuclear Information System (INIS)

    Ünal, Şaban; Yilmaz, Tuncay

    2015-01-01

    Air-conditioning compressors of the buses are usually operated with the power taken from the engine of the buses. Therefore, an improvement in the air-conditioning system will reduce the fuel consumption of the buses. The improvement in the coefficient of performance (COP) of the air-conditioning system can be provided by using the two-phase ejector as an expansion valve in the air-conditioning system. In this study, the thermodynamic analysis of bus air-conditioning system enhanced with a two-phase ejector and two evaporators is performed. Thermodynamic analysis is made assuming that the mixing process in ejector occurs at constant cross-sectional area and constant pressure. The increase rate in the COP with respect to conventional system is analyzed in terms of the subcooling, condenser and evaporator temperatures. The analysis shows that COP improvement of the system by using the two phase ejector as an expansion device is 15% depending on design parameters of the existing bus air-conditioning system. - Highlights: • Thermodynamic analysis of the two-phase ejector refrigeration system. • Analysis of the COP increase rate of bus air-conditioning system. • Analysis of the entrainment ratio of the two-phase ejector refrigeration system

  15. Variable structure TITO fuzzy-logic controller implementation for a solar air-conditioning system

    Energy Technology Data Exchange (ETDEWEB)

    Lygouras, J.N.; Pachidis, Th. [Laboratory of Electronics, School of Electrical and Computer Engineering, Democritus University of Thrace, GR-67100 Xanthi (Greece); Kodogiannis, V.S. [Centre for Systems Analysis, School of Computer Science, University of Westminster, London HA1 3TP (United Kingdom); Tarchanidis, K.N. [Department of Petroleum Technology, Technological Education Institute of Kavala, GR-65404, Kavala (Greece); Koukourlis, C.S. [Laboratory of Telecommunications, School of Electrical and Computer Engineering, Democritus University of Thrace, GR-67100 Xanthi (Greece)

    2008-04-15

    The design and implementation of a Two-Input/Two-Output (TITO) variable structure fuzzy-logic controller for a solar-powered air-conditioning system is described in this paper. Two DC motors are used to drive the generator pump and the feed pump of the solar air-conditioner. The first affects the temperature in the generator of the solar air-conditioner, while the second, the pressure in the power loop. The difficulty of Multi-Input/Multi-Output (MIMO) systems control is how to overcome the coupling effects among each degree of freedom. First, a traditional fuzzy-controller has been designed, its output being one of the components of the control signal for each DC motor driver. Secondly, according to the characteristics of the system's dynamics coupling, an appropriate coupling fuzzy-controller (CFC) is incorporated into a traditional fuzzy-controller (TFC) to compensate for the dynamic coupling among each degree of freedom. This control strategy simplifies the implementation problem of fuzzy control, but can also improve the control performance. This mixed fuzzy controller (MFC) can effectively improve the coupling effects of the systems, and this control strategy is easy to design and implement. Experimental results from the implemented system are presented. (author)

  16. Exergy storage to exploit solar energy in air conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Navarrete-Gonzalez, J.J.; Torres-Reyes, E. [Guanajuato Univ., Guanajuato (Mexico). Inst. de Investigaciones Cientificas; Cervantes-de Gortari, J.G. [Univ. of Cuidad, Mexico City (Mexico). Dept. de Termoenergia y Mejoramiento Ambiental

    2006-07-01

    A thermodynamic procedure was developed to analyze the exergy of a rock bed thermal storage unit that used solar power to acclimatize a pig farm. Thermal behaviour was described by means of a control volume that included the entire system and assumed a unidirectional air flow and an adiabatic process. The thermodynamic properties of the system were determined as a function of the experimental temperature profiles developed during thermal storage from solar to thermal energy conversion provided by a solar collector at a fixed mass rate of air flow. Experimental data were used to calculate the energy yield and to determine the entropy generation inside the system. The aim of the study was to determine how well the thermodynamic model matched the real data obtained experimentally during normal operating conditions. Results indicated that an exergy accumulation existed inside the control volume, which was the net result of the energy gain during the heating process. However, entropy generation due to irreversibilities was studied for just 1 air flow. Further research is needed to establish a semi-empirical model of the process with the minimum of entropy generation. It was concluded that the thermal energy storage system was suitable for use in pig farms. 5 refs., 8 figs.

  17. Multi-gigabit optical interconnects for next-generation on-board digital equipment

    Science.gov (United States)

    Venet, Norbert; Favaro, Henri; Sotom, Michel; Maignan, Michel; Berthon, Jacques

    2017-11-01

    Parallel optical interconnects are experimentally assessed as a technology that may offer the high-throughput data communication capabilities required to the next-generation on-board digital processing units. An optical backplane interconnect was breadboarded, on the basis of a digital transparent processor that provides flexible connectivity and variable bandwidth in telecom missions with multi-beam antenna coverage. The unit selected for the demonstration required that more than tens of Gbit/s be supported by the backplane. The demonstration made use of commercial parallel optical link modules at 850 nm wavelength, with 12 channels running at up to 2.5 Gbit/s. A flexible optical fibre circuit was developed so as to route board-to-board connections. It was plugged to the optical transmitter and receiver modules through 12-fibre MPO connectors. BER below 10-14 and optical link budgets in excess of 12 dB were measured, which would enable to integrate broadcasting. Integration of the optical backplane interconnect was successfully demonstrated by validating the overall digital processor functionality.

  18. Effects of anthropogenic heat due to air-conditioning systems on an extreme high temperature event in Hong Kong

    Science.gov (United States)

    Wang, Y.; Li, Y.; Di Sabatino, S.; Martilli, A.; Chan, P. W.

    2018-03-01

    Anthropogenic heat flux is the heat generated by human activities in the urban canopy layer, which is considered the main contributor to the urban heat island (UHI). The UHI can in turn increase the use and energy consumption of air-conditioning systems. In this study, two effective methods for water-cooling air-conditioning systems in non-domestic areas, including the direct cooling system and central piped cooling towers (CPCTs), are physically based, parameterized, and implemented in a weather research and forecasting model at the city scale of Hong Kong. An extreme high temperature event (June 23-28, 2016) in the urban areas was examined, and we assessed the effects on the surface thermal environment, the interaction of sea-land breeze circulation and urban heat island circulation, boundary layer dynamics, and a possible reduction of energy consumption. The results showed that both water-cooled air-conditioning systems could reduce the 2 m air temperature by around 0.5 °C-0.8 °C during the daytime, and around 1.5 °C around 7:00-8:00 pm when the planetary boundary layer (PBL) height was confined to a few hundred meters. The CPCT contributed around 80%-90% latent heat flux and significantly increased the water vapor mixing ratio in the atmosphere by around 0.29 g kg-1 on average. The implementation of the two alternative air-conditioning systems could modify the heat and momentum of turbulence, which inhibited the evolution of the PBL height (a reduction of 100-150 m), reduced the vertical mixing, presented lower horizontal wind speed and buoyant production of turbulent kinetic energy, and reduced the strength of sea breeze and UHI circulation, which in turn affected the removal of air pollutants. Moreover, the two alternative air-conditioning systems could significantly reduce the energy consumption by around 30% during extreme high temperature events. The results of this study suggest potential UHI mitigation strategies and can be extended to

  19. Experimental and Numerical Study of the Radiant Induction-Unit and the Induction Radiant Air-Conditioning System

    Directory of Open Access Journals (Sweden)

    Qiang Si

    2016-12-01

    Full Text Available In this paper we proposed the novel air-conditioning system which combined induction ventilation and radiant air-conditioning. The indoor terminal device is the radiant induction-unit (RIDU. The RIDU is the induction unit combined with the pore radiant panel on which the copper pipes with rigid aluminum diffusion fins are installed. The two-stage evaporator chiller with the non-azeotropic mixture refrigerant is utilized in the system to reduce the initial investment in equipment. With the performance test and the steady state heat transfer model based on the theory of radiative heat transfer, the relationship between the induction ratio of the RIDU and the characteristic of the air supply was studied. Based on this, it is verified that the RIDU has a lower dew-point temperature and better anti-condensation performance than a traditional plate-type radiant panel. The characteristics of the radiation and convection heat transfer of the RIDU were studied. The total heat exchange of the RIDU can be 16.5% greater than that of the traditional plate-type radiant terminal.

  20. Capability of air filters to retain airborne bacteria and molds in heating, ventilating and air-conditioning (HVAC) systems.

    Science.gov (United States)

    Möritz, M; Peters, H; Nipko, B; Rüden, H

    2001-07-01

    The capability of air filters (filterclass: F6, F7) to retain airborne outdoor microorganisms was examined in field experiments in two heating, ventilating and air conditioning (HVAC) systems. At the beginning of the 15-month investigation period, the first filter stages of both HVAC systems were equipped with new unused air filters. The number of airborne bacteria and molds before and behind the filters were determined simultaneously in 14 days-intervals using 6-stage Andersen cascade impactors. Under relatively dry ( 12 degrees C) outdoor air conditions air filters led to a marked reduction of airborne microorganism concentrations (bacteria by approximately 70% and molds by > 80%). However, during long periods of high relative humidity (> 80% R. H.) a proliferation of bacteria on air filters with subsequent release into the filtered air occurred. These microorganisms were mainly smaller than 1.1 microns therefore being part of the respirable fraction. The results showed furthermore that one possibility to avoid microbial proliferation is to limit the relative humidity in the area of the air filters to 80% R. H. (mean of 3 days), e.g. by using preheaters in front of air filters in HVAC-systems.

  1. Dictionary of heating and air conditioning. Woerterbuch der Heizungs- und Klimatechnik

    Energy Technology Data Exchange (ETDEWEB)

    Laege, K

    1981-01-01

    This German-English and English-German dictionary includes some 4000 technical terms of the field of heating and air conditioning engineering. It represents the latest state of this technical terminology.

  2. Analysis and simulation of mobile air conditioning system coupled with engine cooling system

    International Nuclear Information System (INIS)

    Qi, Zhao-gang; Chen, Jiang-ping; Chen, Zhi-jiu

    2007-01-01

    Many components of the mobile air conditioning system and engine cooling system are closely interrelated and make up the vehicle climate control system. In the present paper, a vehicle climate control system model including air conditioning system and engine cooling system has been proposed under different operational conditions. All the components have been modeled on the basis of experimental data. Based on the commercial software, a computer simulation procedure of the vehicle climate control system has been developed. The performance of the vehicle climate control system is simulated, and the calculational data have good agreement with experimental data. Furthermore, the vehicle climate control simulation results have been compared with an individual air conditioning system and engine cooling system. The influences between the mobile air conditioning system and the engine cooling system are discussed

  3. Heating, Ventilation and Air-Conditioning Systems, Part of Indoor Air Quality Design Tools for Schools

    Science.gov (United States)

    The main purposes of a Heating, Ventilation, and Air-Conditioning system are to help maintain good indoor air quality through adequate ventilation with filtration and provide thermal comfort. HVAC systems are among the largest energy consumers in schools.

  4. Transitioning to Low-GWP Alternatives in Motor Vehicle Air Conditioning Systems

    Science.gov (United States)

    This fact sheet provides information on low-GWP alternatives in newly manufactured motor vehicle air conditioning systems. It discusses HFC alternatives, market trends, challenges to market entry for alternatives, and potential solutions.

  5. History of ventilation and of air conditioning in Dolni Rozinka uranium mines

    International Nuclear Information System (INIS)

    Voltr, S.

    1987-01-01

    At a time of the start of mining operations in the Dolni Rozinka uranium mine, ventilation had been provided using the underpressure technique with diagonal winding shafts. From 1967 the overpressure system had been used. The system is described in detail and its constraints are listed. In 1983, on the basis of an analysis and model tests, the ventilation system was replaced by a underpressure system which satisfied the current hygiene specifications, was costsaving and reliable. Since 1985, an air conditioning system has been in operation featuring mobile cooling units and a closed-circuit air conditioning water system that is separated from the mining water pumping system. In view of the favourable temperature factors of the deposit, the mobile air conditioning units are only installed in blind headings. When the through-flow wind stream is achieved, air conditioning is abandoned. (J.B.). 2 figs., 5 refs

  6. Performance of desiccant air conditioning system with geothermal energy under different climatic conditions

    International Nuclear Information System (INIS)

    El-Agouz, S.A.; Kabeel, A.E.

    2014-01-01

    Highlights: • The performance of the hybrid air conditioning system is studied. • The influence of important operating parameters are estimated. • The ventilation, makeup and mix cycles are investigated at different climate. • The highest COP of the hybrid air conditioning system is 1.03. • The hybrid system provides a human thermal comfort at different climates. - Abstract: Energy saving still and continue a major seek in our life, due to the continuous increase in energy consumptions. So, a desiccant air conditioning system with geothermal energy is conducted in the current study. The thermal analysis of air conditioning system with its different components desiccant wheel, solar collector, heat exchanger, ground heat exchanger and water spray evaporative cooler is presented. Three different air conditioning cycles are simulated in the current study for different zones like: hot-dry zone, warm-dry zone, hot-humid zone and the warm-humid zone. The results show that the desiccant air conditioning system successfully provides a better thermal comfort condition in different climates. This hybrid system significantly decreases the supplied air temperature from 12.7 to 21.7 °C at different climate zones. When ω in , air and T Reg increasing, COP decreases and the ventilation cycle provides the better COP. The highest COP value of the desiccant air conditioning system is about 1.03 while the lowest value is about 0.15. The SHR of makeup cycle is higher than that ventilation cycle at warm and hot-humid zone and vice versa at warm and hot-dry zone. The highest SHR value of the desiccant air conditioning system is about 0.99 while the lowest value is about 0.2. The T sup,air , ω sup,air , COP and SHR isolines may easily be used for pre-evaluating of various cooling cycles in different climates. The hybrid system provides a human thermal comfort at different climates

  7. 2014 German refrigeration and air conditioning meeting. Proceedings; Deutsche Kaelte- und Klimatagung 2014. Tagungsbericht

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-07-01

    The proceedings of the 2014 German refrigeration and air conditioning meeting contain contributions on the following topics: cryotechnology, fundamentals and materials for the refrigeration and heat pump technology, devices and components for the refrigeration and heat pump technology, applications of refrigeration technologies, air conditioning technology and heat pump applications, cryotechnology in biology and medicine, heat transfer and ventilation, guidelines and legal topics, refrigerant fluid - oil mixtures, control and surveillance, simulation and control, ambient air.

  8. Combined desalination and solar-assisted air-conditioning system

    International Nuclear Information System (INIS)

    Gude, Veera Gnaneswar; Nirmalakhandan, Nagamany

    2008-01-01

    Analysis of a new desalination process utilizing low grade thermal energy is presented. In this process, fresh water is distilled from saline water under near-vacuum pressures created by passive means, enabling low-temperature distillation with lower energy requirements. The energy for low-temperature distillation is provided by a thermal energy storage (TES) system maintained at 55 deg. C utilizing any low grade waste heat source. In this study, heat rejected by the condenser of a modified absorption refrigeration system (ARS) is evaluated as a possible source to drive this desalination process. The energy for the generator of the ARS is provided by a combination of solar collector system and grid power. Results of this study show that the thermal energy rejected by an ARS of cooling capacity of 3.25 kW (0.975 tons of refrigeration) along with an additional energy input of 208 kJ/kg of desalinated water is adequate to produce desalinated water at an average rate of 4.5 kg/h. This energy consumption is competitive with that of the multi-stage flash distillation process of similar capacity (338 kJ/kg). An integrated process model and performance curves of the proposed approach are presented in this paper. Effects of process parameters on the performance of the system are also presented

  9. Ice Storage Air-Conditioning System Simulation with Dynamic Electricity Pricing: A Demand Response Study

    Directory of Open Access Journals (Sweden)

    Chi-Chun Lo

    2016-02-01

    Full Text Available This paper presents an optimal dispatch model of an ice storage air-conditioning system for participants to quickly and accurately perform energy saving and demand response, and to avoid the over contact with electricity price peak. The schedule planning for an ice storage air-conditioning system of demand response is mainly to transfer energy consumption from the peak load to the partial-peak or off-peak load. Least Squares Regression (LSR is used to obtain the polynomial function for the cooling capacity and the cost of power consumption with a real ice storage air-conditioning system. Based on the dynamic electricity pricing, the requirements of cooling loads, and all technical constraints, the dispatch model of the ice-storage air-conditioning system is formulated to minimize the operation cost. The Improved Ripple Bee Swarm Optimization (IRBSO algorithm is proposed to solve the dispatch model of the ice storage air-conditioning system in a daily schedule on summer. Simulation results indicate that reasonable solutions provide a practical and flexible framework allowing the demand response of ice storage air-conditioning systems to demonstrate the optimization of its energy savings and operational efficiency and offering greater energy efficiency.

  10. A simulation Model of the Reactor Hall Ventilation and air Conditioning Systems of ETRR-2

    International Nuclear Information System (INIS)

    Abd El-Rahman, M.F.

    2004-01-01

    Although the conceptual design for any system differs from one designer to another. each of them aims to achieve the function of the system required. the ventilation and air conditioning system of reactors hall is one of those systems that really differs but always dose its function for which it is designed. thus, ventilation and air conditioning in some reactor hall constitute only one system whereas in some other ones, they are separate systems. the Egypt Research Reactor-2 (ETRR-2)represents the second type. most studies conducted on ventilation and air conditioning simulation models either in traditional building or for research rectors show that those models were not designed similarly to the model of the hall of ETRR-2 in which ventilation and air conditioning constitute two separate systems.besides, those studies experimented on ventilation and air conditioning simulation models of reactor building predict the temperature and humidity inside these buildings at certain outside condition and it is difficult to predict when the outside conditions are changed . also those studies do not discuss the influences of reactor power changes. therefore, the present work deals with a computational study backed by infield experimental measurements of the performance of the ventilation and air conditioning systems of reactor hall during normal operation at different outside conditions as well as at different levels of reactor power

  11. Fuzzy logic controller implementation for a solar air-conditioning system

    International Nuclear Information System (INIS)

    Lygouras, J.N.; Botsaris, P.N.; Vourvoulakis, J.; Kodogiannis, V.

    2007-01-01

    The implementation of a variable structure fuzzy logic controller for a solar powered air conditioning system and its advantages are investigated in this paper. Two DC motors are used to drive the generator pump and the feed pump of the solar air-conditioner. Two different control schemes for the DC motors rotational speed adjustment are implemented and tested: the first one is a pure fuzzy controller, its output being the control signal for the DC motor driver. A 7 x 7 fuzzy matrix assigns the controller output with respect to the error value and the derivative of the error. The second scheme is a two-level controller. The lower level is a conventional PID controller, and the higher level is a fuzzy controller acting over the parameters of the low level controller. Step response of the two control loops are presented as experimental results. The contribution of this design is that in the control system, the fuzzy logic is implemented through software in a common, inexpensive, 16-bit microcontroller, which does not have special abilities for fuzzy control

  12. Effect of air condition on AP-1000 containment cooling performance in station black out accident

    International Nuclear Information System (INIS)

    Hendro Tjahjono

    2015-01-01

    AP1000 reactor is a nuclear power plant generation III+ 1000 MWe which apply passive cooling concept to anticipate accidents triggered by the extinction of the entire supply of electrical power or Station Black Out (SBO). In the AP1000 reactor, decay heat disposal mechanism conducted passively through the PRHR-IRWST and subsequently forwarded to the reactor containment. Containment externally cooled through natural convection in the air gap and through evaporation cooling water poured on the outer surface of the containment wall. The mechanism of evaporation of water into the air outside is strongly influenced by the conditions of humidity and air temperature. The purpose of this study was to determine the extent of the influence of the air condition on cooling capabilities of the AP1000 containment. The method used is to perform simulations using Matlab-based analytical calculation model capable of estimating the power of heat transferred. The simulation results showed a decrease in power up to 5% for relative humidity rose from 10% to 95%, while the variation of air temperature of 10°C to 40°C, the power will decrease up to 15%. It can be concluded that the effect of air temperature increase is much more significant in lowering the containment cooling ability compared with the increase of humidity. (author)

  13. Adsorption cold storage system with zeolite-water working pair used for locomotive air conditioning

    International Nuclear Information System (INIS)

    Lu, Y.Z.; Wang, R.Z.; Zhang, M.; Jiangzhou, S.

    2003-01-01

    Adsorption cold storage has lately attracted attention for its large storage capacity and zero cold energy loss during the storing process. Thermodynamic and experimental studies on the cold storage capacity and the cold discharging process, in which the adsorber is either air cooled or adiabatic, have been presented. An adsorption cold storage system with zeolite-water working pair has been developed, and some operating results are summarized. This system is used for providing air conditioning for the driver's cab of an internal combustion locomotive. Unlike a normal adsorption air conditioner, the system starts running with the adsorption process, during which the cold energy stored is discharged, and ends running with the generation process. The adsorbent temperature decreases during the cold storing period between two runs. The refrigeration power output for the whole running cycle is about 4.1 kW. It appears that such a system is quite energetically efficient and is comparatively suitable for providing discontinuous refrigeration capacity when powered by low grade thermal energy, such as industrial exhausted heat or solar energy

  14. Fuzzy logic controller implementation for a solar air-conditioning system

    Energy Technology Data Exchange (ETDEWEB)

    Lygouras, J.N.; Vourvoulakis, J. [Laboratory of Electronics, School of Electrical and Computer Engineering, Democritus University of Thrace, Vas. Sofias 12, 67100 Xanthi (Greece); Botsaris, P.N. [Laboratory of Materials, Processes and Mechanical Design, School of Production and Management Engineering, Democritus University of Thrace 67100 Xanthi (Greece); Kodogiannis, V. [Centre for Systems Analysis, School of Computer Science, University of Westminster, London, HA1 3TP (United Kingdom)

    2007-12-15

    The implementation of a variable structure fuzzy logic controller for a solar powered air conditioning system and its advantages are investigated in this paper. Two DC motors are used to drive the generator pump and the feed pump of the solar air-conditioner. Two different control schemes for the DC motors rotational speed adjustment are implemented and tested: the first one is a pure fuzzy controller, its output being the control signal for the DC motor driver. A 7 x 7 fuzzy matrix assigns the controller output with respect to the error value and the derivative of the error. The second scheme is a two-level controller. The lower level is a conventional PID controller, and the higher level is a fuzzy controller acting over the parameters of the low level controller. Step response of the two control loops are presented as experimental results. The contribution of this design is that in the control system, the fuzzy logic is implemented through software in a common, inexpensive, 16-bit microcontroller, which does not have special abilities for fuzzy control. (author)

  15. Power, heat and chilliness with natural gas - fuel cells and air conditioning

    International Nuclear Information System (INIS)

    Krein, Stephan; Ruehling, Karin

    1999-01-01

    A new and innovative concept of the supply with power, heat and chilliness will realise in the new Malteser-hospital in Kamenz. The core of this demonstration-plant are a fuel cell, an adsorption cooling machine as well as multi-solar collectors. The fuel cell has two goals. Primary it produces power for the own demand. The selected dimension guarantees, that the power will consume nearly continuously. Secondly the produced heat of the fuel cell (and the solar-heat too) will use for heating and preparation of warm water. In the summer, the heat will use for the adsorption cooling machine, which produces chilliness for air-conditioning. The advantage in the face of common concepts of combining power and heat is the high-efficiently use of the fuel-energy for electric power generation on the one hand. Fuel cells work with high efficiency also at partial load. On the other hand, with the adsorption cooling machine the produced heat of fuel cell and multi-solar collectors can be used also in the summer. First experiences with this concept show, that an optimised co-operation of the components with an adaptive, self-learning control system based on the weather forecast as well as various storages for heat and chilliness can be achieve. A continuously operation, high fuel utilisation and reduced environmental pollution can be demonstrated. (author)

  16. Generation of domestic waste electrical and electronic equipment on Fernando de Noronha Island: qualitative and quantitative aspects.

    Science.gov (United States)

    Araujo, Dhiego Raphael Rodrigues; de Oliveira, José Diego; Selva, Vanice Fragoso; Silva, Maisa Mendonça; Santos, Simone Machado

    2017-08-01

    The accelerated growth trajectory of waste electrical and electronic equipment (WEEE) is a matter of concern for governments worldwide. In developing countries, the problem is more complex because municipal waste management is still a challenge for municipalities. Fernando de Noronha Island, an environmentally protected area, has a transfer station for solid waste before it is sent to the final destination abroad, which is different waste management model to most urban areas. In order to check the specifics of management of WEEE, this study aimed to qualitatively and quantitatively evaluate the generation of this type of waste on the main island of Fernando de Noronha, taking into consideration aspects related to consumption habits and handling of waste. During the in situ research, a questionnaire was applied to a sample of 83 households. The results provide a picture of the generation of WEEE for a period of 1 year, when a production of 1.3 tons of WEEE was estimated. Relationships between education level and monthly income and between education level and number of plasma/LCD TVs and washing machines were confirmed. Another important result is that only two socioeconomic variables (monthly income and education level) are related to two recycling behavior variables. In addition, the population and government treat WEEE as ordinary waste, ignoring its contaminant potential. Despite the existence of relevant legislation concerning the treatment and disposal of WEEE, additional efforts will be required by the government in order to properly manage this type of waste on the island.

  17. Procedure for qualify class 1E equipment for nuclear power generating stations; Kvalifikacija elektroopreme za stjecanje klase 1E u nuklearnim elektranama

    Energy Technology Data Exchange (ETDEWEB)

    Smiljanic, D [' Rade Koncar' Institut, Zagreb (Yugoslavia)

    1983-07-01

    This paper describes the basic requirements for qualifying Class 1E equipment and systems that are to be used in nuclear power generating stations. The requirements presented include the principles, procedures and methods of qualification. The qualification requirements will confirm the adequacy of the equipment design under normal, abnormal, design basis event, post design basis event and containment test conditions for the performance of Class 1 E functions. The presented methods of qualification are in accordance with IEEE Standards and other standards (IEC, JUS, DIN, etc,), and have the primary role to provide guidance for demonstrating the qualification of Class 1E equipment produced by 'Rade Koncar'.(author)

  18. Commissioning and maintenance experience on mechanical equipment in steam generators of captive power plant at HWP, Manuguru (Paper No. 5.3)

    International Nuclear Information System (INIS)

    Bhatnagar, R.; Sinha, Ashok; Mohan Rao, A.C.

    1992-01-01

    Heavy Water Project (Manuguru) is having a captive power plant to cater to the demands of steam and power for the main plant. During the commissioning and initial run of the steam generators and their auxiliaries, teething/initial problems were encountered in nearly all the equipment of the steam generators. This paper briefly describes some of the major problems faced during the commissioning of the steam generators. (author). 4 figs

  19. Experimental study of the behavior of a hybrid ejector-based air-conditioning system with R134a

    International Nuclear Information System (INIS)

    Wang, Hao; Cai, Wenjian; Wang, Youyi; Yan, Jia; Wang, Lei

    2016-01-01

    Highlights: • We conduct experiment on two working mode of system and compare their performance. • We examine the influence of different pressure on system performance. • We examine the area ratio effect on ejector performance. • The system is sensitive to evaporating and generating pressure. • The COP improvement is around 34% under hybrid mode. - Abstract: A hybrid ejector-based air-conditioning system which combines a vapor compression cycle and a ejector refrigeration cycle was developed. The waste heat energy from automobile is applied as driven source towards ejector refrigeration cycle. Two ejectors with different mixing chamber diameters are applied separately for performance test and the system is operated under different working modes. The effect of generating, condensing and evaporating pressure on system performance are studied experimentally. The effect of ejector geometry parameters on ejector performance is also investigated. The performance comparison between two working modes is made and the results indicate that (1) the performance of proposed system is sensitive to the three pressures; (2) the coefficient of performance (COP) of hybrid ejector-based air-conditioning system is around 34% higher than that of conventional compressor based system which implies a potential energy saving ability of proposed hybrid system.

  20. IEEE Std 600: IEEE trial-use standard requirements for organizations that conduct qualification testing of safety systems equipment for use in nuclear power generating stations

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    The purpose of this standard is to provide requirements for establishing a program for conducting qualification tests of safety systems equipment used in nuclear power generating stations. Compliance with the requirements of this standard does not assure the adequacy of the qualification tests performed. This standard applies to organizations that conduct qualification tests on equipment that has a definable safety function and is an identifiable part of a safety system for use in nuclear power generating stations. It requires a technical program, a quality assurance program, and a demonstrated ability to meet specified technical requirements. It does not apply to materials tests, production tests, normal performance testing, qualification by analysis, qualification by operating experience, or reliability tests such as diesel-generator multiple start tests. The intent of this standard is to achieve greater consistency, reliability, and reproducibility of test results and to provide adequate control of qualification testing of safety systems equipment

  1. Sterilization efficacy of ultraviolet irradiation on microbial aerosols under dynamic airflow by experimental air conditioning systems

    International Nuclear Information System (INIS)

    Nakamura, Hiroshi

    1987-01-01

    In order to know the sterilization efficacy of ultraviolet irradiation on microbial aerosols, the size and the weight of the aerosol particles were evaluated, and these were irradiated under dynamic air flow created by an experimental air conditioning system. The experimental apparatus consisted of a high efficiency particulate air (HEPA) filter, an aerosol generator, spiral UV lamps placed around a quart glass tube, an Andersen air sampler and a vacuum pump. They were connected serially by stainless steel ducts (85 mm in diameter, 8 m in length). Six types of microbial aerosols generated from an ultrasonic nebulizer were irradiated by UV rays (wavelength 254 nm, mean density 9400 μW/cm 2 ). Their irradiation time ranged from 1.0 to 0.0625 seconds. The microbial aerosols were collected onto the trypticase soy agar (TSA) medium in the Andersen air sampler. After incubation, the number of colony forming units (CFU) were counted, and converted to particle counts. The diameter of microbial aerosol particles calculated by their log normal distribution were found to match the diameter of a single bacteria cell measured by a microscope. The sterilization efficacy of UV in standard airflow conditions (0.5 sec. irradiation) were found to be over 99.5 % in Staphylococcus aureus, Staphylococcus epidermidis, Serratia marcescens, Bacillus subtilis (vegetative cell) and Bacillus subtilis (spore) and 67 % in Aspergillus niger (conidium). In A. niger, which was the most resistant microbe to UV irradiation, the efficacy rose up to 79 % when irradiated for 1.0 sec., and it was observed that the growth speed of the colonies was slower than that of the controls. It was thought that UV rays caused some damage to the proliferation of A. niger cells. (author)

  2. A Novel Distributed Economic Model Predictive Control Approach for Building Air-Conditioning Systems in Microgrids

    Directory of Open Access Journals (Sweden)

    Xinan Zhang

    2018-04-01

    Full Text Available With the penetration of grid-connected renewable energy generation, microgrids are facing stability and power quality problems caused by renewable intermittency. To alleviate such problems, demand side management (DSM of responsive loads, such as building air-conditioning system (BACS, has been proposed and studied. In recent years, numerous control approaches have been published for proper management of single BACS. The majority of these approaches focus on either the control of BACS for attenuating power fluctuations in the grid or the operating cost minimization on behalf of the residents. These two control objectives are paramount for BACS control in microgrids and can be conflicting. As such, they should be considered together in control design. As individual buildings may have different owners/residents, it is natural to control different BACSs in an autonomous and self-interested manner to minimize the operational costs for the owners/residents. Unfortunately, such “selfish” operation can result in abrupt and large power fluctuations at the point of common coupling (PCC of the microgrid due to lack of coordination. Consequently, the original objective of mitigating power fluctuations generated by renewable intermittency cannot be achieved. To minimize the operating costs of individual BACSs and simultaneously ensure desirable overall power flow at PCC, this paper proposes a novel distributed control framework based on the dissipativity theory. The proposed method achieves the objective of renewable intermittency mitigation through proper coordination of distributed BACS controllers and is scalable and computationally efficient. Simulation studies are carried out to illustrate the efficacy of the proposed control framework.

  3. Comparative study of operation of condensing and traditional boilers equipped with the ORC module for electricity generation

    Directory of Open Access Journals (Sweden)

    Mikielewicz Dariusz

    2017-01-01

    Full Text Available Condensing technology applied to boilers is to make full use of thermal energy contained in the fuel. That means that additionaly the heat from condensation of exhaust gases can be used for the purposes of heating the domestic hot water and to cover the demand for central heating. The study analyzed the operation of the “traditional” boiler equipped with the ORC module as the similar arrangement but with the condensing boiler. In the case of a conventional boiler there is noted a greater fuel consumption and the greater power generated than in the case of the unit with the condensing boiler. Postulated is the indicator in the form of a ratio of turbine power to the mass flow rate of fuel, which in turn gives a higher value for the condensing boiler, thus demonstrating that the operation of condensing boiler ORC module will be more economical. Perspective domestic micro CHP with ORC should be installed in boilers with recovery of heat from condensation from the exhaust gases.

  4. Air Conditioning Compressor Air Leak Detection by Image Processing Techniques for Industrial Applications

    Directory of Open Access Journals (Sweden)

    Pookongchai Kritsada

    2015-01-01

    Full Text Available This paper presents method to detect air leakage of an air conditioning compressor using image processing techniques. Quality of air conditioning compressor should not have air leakage. To test an air conditioning compressor leak, air is pumped into a compressor and then submerged into the water tank. If air bubble occurs at surface of the air conditioning compressor, that leakage compressor must be returned for maintenance. In this work a new method to detect leakage and search leakage point with high accuracy, fast, and precise processes was proposed. In a preprocessing procedure to detect the air bubbles, threshold and median filter techniques have been used. Connected component labeling technique is used to detect the air bubbles while blob analysis is searching technique to analyze group of the air bubbles in sequential images. The experiments are tested with proposed algorithm to determine the leakage point of an air conditioning compressor. The location of the leakage point was presented as coordinated point. The results demonstrated that leakage point during process could be accurately detected. The estimation point had error less than 5% compared to the real leakage point.

  5. Classified directory of the field of refrigeration and air conditioning technology 2006. Register of the expert companies in the field of refrigeration and air conditioning plants craft including a supply and service list - register of the suppliers in the field of refrigeration and air conditioning technology including the complete ranges of material groups offered - register of expert schools, technical experts, technical expert information and norms; Branchenbuch der Kaelte- und Klimatechnik 2006. Verzeichnis der Fachbetriebe des Kaelte- und Klimaanlagenbauerhandwerks mit Liefer- und Leistungsangebot - Verzeichnis der Lieferanten von Kaelte- und Klimatechnik mit vollstaendigem Warengruppenangebot - Verzeichnis von Fachschulen, Sachverstaendigen u.v.a. - Technische Fachinformationen und Normen

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    The present edition of the ''Classified directory of the field of refrigeration and air conditioning technology'' 2006 contains useful addresses, data and facts of the field: (a) approximately 1.500 addresses of expert companies in the field of refrigeration and air conditioning technology; (b) a register of suppliers and material groups in the field of refrigeration and air conditioning technology; (c) a technical part containing the most important norms of the field, laws and regulations in order to inform the reader for his daily work. The reference book is supposed to provide a good overview for the work in the field of technical building equipment. (orig./AKF)

  6. MOPABA-H2 - Computer code for calculation of hydrogen generation and distribution in the equipment of power plants with WWER type reactors in design modes of operation

    International Nuclear Information System (INIS)

    Arkhipov, O.P.; Kharitonov, Yu.V.; Shumskiy, A.M.; Kabakchi, S.A.

    2002-01-01

    With the aim of ensuring the hydrogen explosive-proof situation in the reactor plant, a complex of scientific-and-research work was carried out including the following: revealing the mechanisms of generation and release of hydrogen in the primary equipment components under design operation modes of the reactor plant with WWER; development of calculation procedure and computer code MOPABA-H2 enabling to determine the hydrogen content in RP equipment components under design operation modes. In the process of procedure development it was found out that the calculation of hydrogen content in the plant equipment requires development of the following main mathematical models: radiochemical processes in the primary coolant which has impurities and added special reagents; absorption of the core ionizing radiation by the coolant; steam-zirconium reaction (during design-basis accident of LOCA type); coolant mass transfer over the reactor plant equipment including transition of the phase boundary by the components of the coolant. (author)

  7. Prediction of thermal sensation in non-air-conditioned buildings in warm climates

    DEFF Research Database (Denmark)

    Fanger, Povl Ole; Toftum, Jørn

    2002-01-01

    The PMV model agrees well with high-quality field studies in buildings with HVAC systems, situated in cold, temperate and warm climates, studied during both summer and winter. In non-air-conditioned buildings in warm climates, occupants may sense the warmth as being less severe than the PMV...... predicts. The main reason is low expectations, but a metabolic rate that is estimated too high can also contribute to explaining the difference. An extension of the PMV model that includes an expectancy factor is introduced for use in non-air-conditioned buildings in warm climates. The extended PMV model...... agrees well with quality field studies in non-air-conditioned buildings of three continents....

  8. Modeling validation and control analysis for controlled temperature and humidity of air conditioning system.

    Science.gov (United States)

    Lee, Jing-Nang; Lin, Tsung-Min; Chen, Chien-Chih

    2014-01-01

    This study constructs an energy based model of thermal system for controlled temperature and humidity air conditioning system, and introduces the influence of the mass flow rate, heater and humidifier for proposed control criteria to achieve the controlled temperature and humidity of air conditioning system. Then, the reliability of proposed thermal system model is established by both MATLAB dynamic simulation and the literature validation. Finally, the PID control strategy is applied for controlling the air mass flow rate, humidifying capacity, and heating, capacity. The simulation results show that the temperature and humidity are stable at 541 sec, the disturbance of temperature is only 0.14 °C, 0006 kg(w)/kg(da) in steady-state error of humidity ratio, and the error rate is only 7.5%. The results prove that the proposed system is an effective controlled temperature and humidity of an air conditioning system.

  9. Extension of the PMV model to non-air-conditioned building in warm climates

    DEFF Research Database (Denmark)

    Fanger, Povl Ole; Toftum, Jørn

    2002-01-01

    The PMV model agrees well with high-quality field studies in buildings with HVAC systems, situated in cold, temperate and warm climates, studied during both summer and winter. In non-air-conditioned buildings in warm climates, occupants may sense the warmth as being less severe than the PMV...... predicts. The main reason is low expectations, but a metabolic rate that is estimated too high can also contribute to explaining the difference. An extension of the PMV model that includes an expectancy factor is introduced for use in non-air-conditioned buildings in warm climates. The extended PMV model...... agrees well with quality field studies in non-air-conditioned buildings of three continents....

  10. Studies of Radon and Radon Progeny in Air Conditioned Rooms in Hospitals

    International Nuclear Information System (INIS)

    Marley, F.; Denman, A.R.; Phillips, P.S.

    1998-01-01

    A series of continuous real-time radon and radon progeny measurements together with passive etched track detector measurements were performed in hospital premises during 1996. In one small room, detailed measurements over several weeks showed that both the radon concentration and the Equilibrium Factor depended on the intermittent operation of a filtered positive pressure displacement air-conditioning system, which was designed to conform to operating theatre standards. The average radon level measured while the air-conditioning was off was almost four times higher than that recorded whilst it was on. The progeny level was over five times higher than that whilst it was on. Thus, the Equilibrium Factor (F), was significantly lower when the air-conditioning was on. Measurements in similar rooms in two hospitals, confirmed that the reduction in radon level was a general finding. Thus staff working in such environments receive significantly lower radiation dose from radon than staff working in nearby normally ventilated rooms. (author)

  11. Numerical Analysis of Exergy for Air-Conditioning Influenced by Ambient Temperature

    Directory of Open Access Journals (Sweden)

    Jing-Nang Lee

    2014-07-01

    Full Text Available The article presents numerical analysis of exergy for air-conditioning influenced by ambient temperature. The model of numerical simulation uses an integrated air conditioning system exposed in varied ambient temperature to observe change of the four main devices, the compressor, the condenser, the capillary, and the evaporator in correspondence to ambient temperature. The analysis devices of the four devices’s exergy influenced by the varied ambient temperature and found that the capillary has unusual increasing exergy loss vs. increasing ambient temperature in comparison to the other devices. The result shows that reducing exergy loss of the capillary influenced by the ambient temperature is the key for improving working efficiency of an air-conditioning system when influence of the ambient temperature is considered. The higher ambient temperature causes the larger pressure drop of capillary and more exergy loss.

  12. Modeling Validation and Control Analysis for Controlled Temperature and Humidity of Air Conditioning System

    Directory of Open Access Journals (Sweden)

    Jing-Nang Lee

    2014-01-01

    Full Text Available This study constructs an energy based model of thermal system for controlled temperature and humidity air conditioning system, and introduces the influence of the mass flow rate, heater and humidifier for proposed control criteria to achieve the controlled temperature and humidity of air conditioning system. Then, the reliability of proposed thermal system model is established by both MATLAB dynamic simulation and the literature validation. Finally, the PID control strategy is applied for controlling the air mass flow rate, humidifying capacity, and heating, capacity. The simulation results show that the temperature and humidity are stable at 541 sec, the disturbance of temperature is only 0.14°C, 0006 kgw/kgda in steady-state error of humidity ratio, and the error rate is only 7.5%. The results prove that the proposed system is an effective controlled temperature and humidity of an air conditioning system.

  13. Optimum selection of solar collectors for a solar-driven ejector air conditioning system by experimental and simulation study

    International Nuclear Information System (INIS)

    Zhang Wei; Ma Xiaoli; Omer, S.A.; Riffat, S.B.

    2012-01-01

    Highlights: ► Three solar collectors have been compared to drive ejector air conditioning system. ► A simulation program was constructed to study the effect parameters. ► The outdoor test were conducted to validate the solar collector modeling. ► Simulation program was found to predict solar collector performance accurately. ► The optimal design of solar collector system was carried out. - Abstract: In this paper, three different solar collectors are selected to drive the solar ejector air conditioning system for Mediterranean climate. The performance of the three selected solar collector are evaluated by computer simulation and lab test. Computer model is incorporated with a set of heat balance equations being able to analyze heat transfer process occurring in separate regions of the collector. It is found simulation and test has a good agreement. By the analysis of the computer simulation and test result, the solar ejector cooling system using the evacuated tube collector with selective surface and high performance heat pipe can be most economical when operated at the optimum generating temperature of the ejector cooling machine.

  14. Does the air condition system in busses spread allergic fungi into driver space?

    Science.gov (United States)

    Sowiak, Małgorzata; Kozajda, Anna; Jeżak, Karolina; Szadkowska-Stańczyk, Irena

    2018-02-01

    The aim of this study was to establish whether the air-conditioning system in buses constitutes an additional source of indoor air contamination with fungi, and whether or not the fungi concentration depends on the period from the last disinfection of the system, combined with replacement of the cabin dust particle filter. The air samples to fungi analysis using impact method were taken in 30 buses (20 with an air-conditioning system, ACS; 10 with a ventilation system, VS) in two series: 1 and 22 weeks after cabin filter replacement and disinfection of the air-conditioning system. During one test in each bus were taken two samples: before the air-conditioning or ventilation system switched on and 6 min after operating of these systems. The atmospheric air was the external background (EB). After 1 week of use of the system, the fungi concentrations before starting of the ACS and VS system were 527.8 and 1053.0 cfu/m 3 , respectively, and after 22 weeks the concentrations were 351.9 and 1069.6 cfu/m 3 , respectively. While in the sample after 6 min of ACS and VS system operating, the fungi concentration after 1 week of use was 127.6 and 233.7 cfu/m 3 , respectively, and after 22 weeks it was 113.3 and 324.9 cfu/m 3 , respectively. Results do not provide strong evidence that air-conditioning system is an additional source of indoor air contamination with fungi. A longer operation of the system promoted increase of fungi concentration in air-conditioned buses only.

  15. Real reflections upon the air-conditioning market in the empire of Harun el Raschid

    Energy Technology Data Exchange (ETDEWEB)

    Piock, R

    1982-04-01

    The conception Middle East is being interpreted in so many ways as the legendary fiction and tales which are being told of the country of the early caliph. Similar is the variety of the climatic zones, the economic systems and the political structure in this region. Homogeneous are really only the national characteristics of the people living in the region (orientals and semites), and their religion (Islam). Normally one understands by the expression - Middle East - the Asiatic States of the Mediterranean Sea and the Arabic States of Asia. These zones comprise climatically etesian climates (Lebanon, parts of Syria), alpine climates (Iraqi Kurdland), desert and grassland climates with rainfalls of 250 mm/annum but also tropical climate (South Jemen). Of similar variety are the characteristics of the states: we find republics, kingdoms and federal states in most instances with one governing class of rich people or party members and a mass of poor people. Fairly uniform are the economics - a state centralism. The state directs and invests, dependent on the country the liberalism of commerce is graduated differently. In rough outlines one can distinguish two climatic zones: a) countries with dry climate, temperatures between 40 and 46/sup 0/C/19% R.H. in summer and 0/sup 0/C/80% R.H. in winter during which water can be used for cooling. b) countries with humid climate, temperatures between 38 and 40/sup 0/C/55% R.H. in summer and -12/sup 0/C/85% R.H. in winter during which water for cooling would be available, but can not be used for physical reasons. The first group includes Syria, large parts of Iraq (excluding the South, Amman-Basrah region), the interior parts of Saudi-Arabia, the second South Iraq, Kuwait, the Gulf States and the coast districts of Saudi-Arabia. This arrangement appears to be significant, because from it emerges the distinct equipment of the air conditioning installations and the problems which arise there from.

  16. In-car particles and cardiovascular health: an air conditioning-based intervention study.

    Science.gov (United States)

    Chuang, Hsiao-Chi; Lin, Lian-Yu; Hsu, Ya-Wen; Ma, Chih-Ming; Chuang, Kai-Jen

    2013-05-01

    Exposure to traffic-related particulate matter (PM) is considered a potential risk for cardiovascular events. Little is known about whether improving air quality in car can modify cardiovascular effects among human subjects during commuting. We recruited a panel of 60 healthy subjects to commute for 2 h by a car equipped with an air conditioning (AC) system during the morning rush hour in Taipei. Operation modes of AC system using outside air (OA-mode), circulating inside air (IA-mode) and turning off (Off-mode) were examined. Repeated measurements of heart rate variability (HRV) indices, PM≤2.5 μm in aerodynamic diameter (PM2.5) and noise level were conducted for each participant in different modes during the commute. We used linear mixed-effects models to associate HRV indices with in-car PM2.5. We found that decreases in HRV indices were associated with increased levels of in-car PM2.5. For Off-mode, an interquartile range (IQR) increase in in-car PM2.5 with 15-min moving average was associated with 2.7% and 4.1% decreases in standard deviation of NN intervals (SDNN) and the square root of the mean of the sum of the squares of differences between adjacent NN intervals (r-MSSD), respectively. During OA and IA modes, participants showed slight decreases in SDNN (OA mode: 0.1%; IA mode: 1.3%) and r-MSSD (OA mode: 1.1%; IA mode: 1.8%) by an IQR increase in in-car PM2.5 with 15-min moving average. We concluded that in-car PM2.5 is associated with autonomic alteration. Utilization of the car's AC system can improve air quality and modify the effects of in-car PM2.5 on HRV indices among human subjects during the commute. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. THE USE OF AIR LAYERS IN BUILDING ENVELOPES FOR ENERGY SAVING DURING AIR CONDITIONING

    Directory of Open Access Journals (Sweden)

    S. N. Osipov

    2017-01-01

    Full Text Available Since there are no large natural energy resources in Belarus, energy savings ought to be a point of the special attention. With this regard it is important to develop modern ways of savings during the process of air conditioning inside new buildings with an air layer in the enclosure, especially in translucent ones. The system of ventilation of air layers in the enclosure of a building has been introduced in which air movement is caused by the gravitational and aerodynamic forces. It makes it possible to arrange further ventilation – a natural, forced or a hybrid one. With the purpose of increasing and streamlining natural draught the partitions are used separating the different parts of air layers. For natural ventilation with the use of gravitational forces the holes in the upper and lower parts of the partitions between adjacent air layers are applied. Natural ventilation in the holes of the partitions is regulated by movable shutters, blinds or other adjusting devices. For combined or forced air exchange between adjacent zones of air layers fans are used pumping air from the air layer zones with a higher temperature to zones of air layers with lower temperature and vice versa. When air exchange is forced, in order to intensify the infiltration of air into zones of air layers jets are laid on a hard surface. In order to cool a multi-layered enclosure of a building, where the movement of air between the air layers (that have been formed by internal partitions is being fulfilled by a natural, forced or combined mode, a part of the air or the total air processed inside the building (i.e. conditioned or non-conditioned air cooler as compared with the outside one is being sent to these strata. Combined or forced flow of the air processed inside the building into the air layers is done through the ducts associated with the output channels of the air conditioners. The internal partitions are equipped with the air valve hole.

  18. Selection of equipment for equipment qualification

    International Nuclear Information System (INIS)

    Torr, K.G.

    1989-01-01

    This report describes the methodology applied in selecting equipment in the special safety systems for equipment qualification in the CANDU 600 MW nuclear generating stations at Gentilly 2 and Point Lepreau. Included is an explanation of the selection procedure adopted and the rationale behind the criteria used in identifying the equipment. The equipment items on the list have been grouped into three priority categories as a planning aid to AECB staff for a review of the qualification status of the special safety systems

  19. Saving 50% of energy in air conditioning and refrigeration; 50% de ahorro de energia en aire acondicionado y refrigeracion

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez De la Fuente, Rodolfo Javier [Instituto para la Proteccion Ambiental de Nuevo Leon-CAINTRA, Nuevo Leon (Mexico); Bolado Tamez, Jaime Antonio [Industrias AlEn S. A. de C. V., Monterrey (Mexico)

    1998-12-31

    Due to the fact that the air conditioning systems represent up to 70% of the energy consumption in our buildings, to the constant raise of the electric tariffs and to the increment of temperatures in Nuevo Leon State, as well as the restrictions on the use of some refrigerant fluids because of its potential damage to the ozone layer (Montreal Protocol) and the preferential use of refrigerants with low global heating potential (Kioto Protocol). The Camara de la Industria de la Transformacion de Nuevo Leon (Nuevo Leon`s Transformation Industry Chamber) through the Instituto para la Proteccion Ambiental de Nuevo Leon (Nuevo Leon`s Institute for Environmental Protection), create the program ECO-REFRIGERATION whose three missions are: Increase the efficiency of air conditioning and refrigeration equipment, promote the substitution of refrigerants and extend the benefits of these projects to the community in general. [Espanol] Debido a que los sistemas de climatizacion representan hasta el 70% de consumo energetico en nuestros inmuebles, al constante incremento de las tarifas electricas, el incremento de las temperaturas en Nuevo Leon, asi como la restriccion del uso de algunos refrigerantes por su potencial de dano de la capa de ozono (Protocolo de Montreal) y el uso preferente de refrigerantes con bajo potencial de calentamiento global (Protocolo de Kioto), la Camara de la Industria de la Transformacion de Nuevo Leon a traves del Instituto para la Proteccion Ambiental de Nuevo Leon crean el Programa ECO-REFRIGERACION cuyas tres misiones son: Incrementar la eficiencia de los equipos de aire acondicionado y refrigeracion, promover la sustitucion de refrigerantes y extender los beneficios de este proyecto a la comunidad en general.

  20. Saving 50% of energy in air conditioning and refrigeration; 50% de ahorro de energia en aire acondicionado y refrigeracion

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez De la Fuente, Rodolfo Javier [Instituto para la Proteccion Ambiental de Nuevo Leon-CAINTRA, Nuevo Leon (Mexico); Bolado Tamez, Jaime Antonio [Industrias AlEn S. A. de C. V., Monterrey (Mexico)

    1999-12-31

    Due to the fact that the air conditioning systems represent up to 70% of the energy consumption in our buildings, to the constant raise of the electric tariffs and to the increment of temperatures in Nuevo Leon State, as well as the restrictions on the use of some refrigerant fluids because of its potential damage to the ozone layer (Montreal Protocol) and the preferential use of refrigerants with low global heating potential (Kioto Protocol). The Camara de la Industria de la Transformacion de Nuevo Leon (Nuevo Leon`s Transformation Industry Chamber) through the Instituto para la Proteccion Ambiental de Nuevo Leon (Nuevo Leon`s Institute for Environmental Protection), create the program ECO-REFRIGERATION whose three missions are: Increase the efficiency of air conditioning and refrigeration equipment, promote the substitution of refrigerants and extend the benefits of these projects to the community in general. [Espanol] Debido a que los sistemas de climatizacion representan hasta el 70% de consumo energetico en nuestros inmuebles, al constante incremento de las tarifas electricas, el incremento de las temperaturas en Nuevo Leon, asi como la restriccion del uso de algunos refrigerantes por su potencial de dano de la capa de ozono (Protocolo de Montreal) y el uso preferente de refrigerantes con bajo potencial de calentamiento global (Protocolo de Kioto), la Camara de la Industria de la Transformacion de Nuevo Leon a traves del Instituto para la Proteccion Ambiental de Nuevo Leon crean el Programa ECO-REFRIGERACION cuyas tres misiones son: Incrementar la eficiencia de los equipos de aire acondicionado y refrigeracion, promover la sustitucion de refrigerantes y extender los beneficios de este proyecto a la comunidad en general.

  1. About Economy of Fuel at Thermal Power Stations due to Optimization of Utilization Diagram of Power-Generating Equipment

    Directory of Open Access Journals (Sweden)

    M. V. Svechko

    2008-01-01

    Full Text Available Problems of rational fuel utilization becomes more and more significant especially for thermal power stations (TPS. Thermal power stations have complicated starting-up diagrams and utilization modes of their technological equipment. Method of diagram optimization of TPS equipment utilization modes has been developed. The method is based on computer analytical model with application of spline-approximation of power equipment characteristics. The method allows to economize fuel consumption at a rate of 15-20 % with accuracy of the predicted calculation not more than 0.25 %.

  2. The chosen needs of Polish restructured coal mines concerning the ventilation and struggling against gas, dust and air-conditioning dangers

    Energy Technology Data Exchange (ETDEWEB)

    Matuszewski, K. [Rudzka Coal Company (Poland)

    2001-07-01

    In this paper the selected needs of Polish coal mines with regard to their ventilation, minimisation of gas, dust and air-shortage dangers are presented. As far as ventilation is concerned: the need to broaden the use of the synchronic inverter cascades for speed regulation of main fans and the delivery of ventilation air duct to ensure a delivery of 11,117 m{sup 3}/s (6,5011,000 m{sup 3}/min) has been shown. As far as gas dangers are concerned there exists a need for the dissemination of dispatcher's help systems, training safety personnel in use of so called synoptic display table, a supply of 0,8311,67 m{sup 3}/s (501,100 m{sup 3}/min) of nitrogen in gaseous state for fire prevention as well as the use of modern mineral and chemical means have been mentioned. In order to help to reduce the dust danger the projected need for a modern generation of dry or wet dust collectors enabling a reduction in dustiness to NDS standards and equipping all longwalls with cutting machines with permanent and working installations of internal sprinklers have been postulated. In the case of air conditioning, the need to install 300 kW movable coolers with 300 kW single gear fans for the supply of 10 m{sup 3}/s (600 m{sup 3}/min) and an overall air pressure increase from 1600 to 2000 Pa has been presented. In the most dangerous coal mines attention has been drawn to the need for the installation and application of stationery coolers operating intermittently. 6 refs.

  3. Modelling and hardware-in-the-loop simulation of the blowout tract components for passenger compartment air conditioning of motor vehicles; Modellierung und Hardware-in-the-Loop-Simulation der Komponenten des Ausblastraktes zur Kraftfahrzeuginnenraumklimatisierung

    Energy Technology Data Exchange (ETDEWEB)

    Michalek, David

    2009-07-01

    The author investigated the modelling and hardware-in-the-loop simulation of components of the blowout tract of motor car air conditioning systems. The control systems and air conditioning systems are gone into, from the air entering the car to the control systems and sensors for monitoring state variables. The function of the control equipment hardware and software was to be analyzed reproducibly in order to save time and cost. The models were verified using available data. Validation criteria were established for the hardware-in-the-loop simulator. On the basis of selected operating conditions, the performance of the air conditioning control unit inside the vehicle was compared with the simulation results and was evaluated on the basis of the established criteria. (orig.)

  4. 2012 German refrigeration and air conditioning meeting. Proceedings; Deutsche Kaelte-Klima-Tagung 2012 Tagungsbericht

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    Within the DKV conference of the Deutscher Kaelte- und Klimatechnischer Verein e.V. (Hanover, Federal Republic of Germany) from 21st to 23rd November, 2012, in Wuerzburg (Federal Republic of Germany) 121 lectures were held according to the following themes: Measurement and process control in cryotechnology; energy storage and energy application; application of cryotechnology in biology and medicine, new concepts and plants; fundamentals and materials for the technology of cold pumps and heat pumps - pool boiling; flow boiling / CO{sub 2}; adsorption processes; adsorption processes / phase change materials; condensation / dehumidification; plants and components of the technology of cold pumps and heat pumps - compressors; expansion and regulation; heat exchanger and reflux cooling; heat exchangers; systems simulation; systems and materials; application of cold - energy controlling / application; foodstuff / supermarket; air conditionings of passenger cars; air-conditioning of electric-powered automobiles; railway air-conditioning / system analyses; standardization and regulations; air conditioning and application of heat pumps - regulation / hardware-in-the-loop; net-zero-energy building; building engineering and simulation; standardization / IAQ / building materials; heat pumps; thermal comfort and performance in office accommodations.

  5. HFC perspectives in air-conditioning and refrigeration; Perspectives HFC en A/C et refrigeration

    Energy Technology Data Exchange (ETDEWEB)

    Fauvarque, P [ELF Atochem, Centre d` Application de Lavallois, 92 (France)

    1998-12-31

    This paper is a series of transparencies dealing with the development of substitutes for the replacement of the R-22 refrigerant in air-conditioning systems (R-134a, R-407C, R-410A), and in industrial refrigeration systems of agriculture and food industry (R-134a and R-404A). (J.S.)

  6. Energy managemant through PCM based thermal storage system for building air-conditioning: Tidel Park, Chennai

    International Nuclear Information System (INIS)

    Nallusamy, N.; Sampath, S.; Velraj, R.

    2006-01-01

    Many modern building are designed for air-conditioning and the amount of electrical energy required for providing air-conditioning can be very significant especially in the tropics. Conservation of energy is major concern to improve the overall efficiency of the system. Integration is energy storage with the conventional system gives a lot of potential for energy saving and long-term economics. Thermal energy storage systems can improve energy management and help in matching supply and demand patterns. In the present work, a detailed study has been done on the existing thermal energy storage system used in the air-conditioning system in Tidel Park, Chennai. The present study focuses on the cool energy storage system. The modes of operation and advantages of such a system for energy management are highlighted. The reason for the adoption of combined storage system and the size of the storage medium in the air-conditioning plant are analyzed. The possibility of using this concept in other cooling and heating applications, such as storage type solar water heating system, has been explored

  7. Potential Evaluation of Solar Heat Assisted Desiccant Hybrid Air Conditioning System

    Science.gov (United States)

    Tran, Thien Nha; Hamamoto, Yoshinori; Akisawa, Atsushi; Kashiwagi, Takao

    The solar thermal driven desiccant dehumidification-absorption cooling hybrid system has superior advantage in hot-humid climate regions. The reasonable air processing of desiccant hybrid air conditioning system and the utility of clean and free energy make the system environment friendly and energy efficient. The study investigates the performance of the desiccant dehumidification air conditioning systems with solar thermal assistant. The investigation is performed for three cases which are combinations of solar thermal and absorption cooling systems with different heat supply temperature levels. Two solar thermal systems are used in the study: the flat plate collector (FPC) and the vacuum tube with compound parabolic concentrator (CPC). The single-effect and high energy efficient double-, triple-effect LiBr-water absorption cooling cycles are considered for cooling systems. COP of desiccant hybrid air conditioning systems are determined. The evaluation of these systems is subsequently performed. The single effect absorption cooling cycle combined with the flat plate collector solar system is found to be the most energy efficient air conditioning system.

  8. Feasibility of a solar-assisted winter air-conditioning system using evaporative air-coolers

    Energy Technology Data Exchange (ETDEWEB)

    El-Awad, Mohamed M. [Mechanical Engineering Department, the University of Khartoum, P.O. Box 321 Khartoum (Sudan)

    2011-07-01

    The paper presents a winter air-conditioning system which is suitable for regions with mildly cold but dry winters. The system modifies the evaporative air-cooler that is commonly used for summer air-conditioning in such regions by adding a heating process after the humidification process. The paper describes a theoretical model that is used to estimate the system's water and energy consumption. It is shown that a 150-LPD solar heater is adequate for air-conditioning a 500 ft3/min (14.4 m3/min) air flow rate for four hours of operation. The maximum air-flow rate that can be heated by a single solar water-heater for four hours of operation is about 900-cfm, unless a solar water heater large than a 250-LPD heater is used. For the 500 ft3/min air flow rate the paper shows that the 150, 200, 250 and 300 LPD solar water-heaters can provide air-conditioning for 4, 6, 8 and 10 hours, respectively, while consuming less energy than the equivalent refrigerated-type air-conditioner.

  9. Development of residential solar air conditioning system for electricity power peak cut 3

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Gwon Jong [Korea Inst. of Energy and Resources, Daeduk (Korea, Republic of)

    1995-12-31

    In this research, the converter rectifier unit of the inverter air conditioner is substituted into the bidirectional PWM converter. The DC/DC power converter is established on the DC link between the photovoltaic array and the inverter air conditioner, and the photovoltaic air conditioning system which can be parallel driven which utility is developed. (author). 35 ref., 112 figs.

  10. Impact of climate change on commercial sector air conditioning energy consumption in subtropical Hong Kong

    International Nuclear Information System (INIS)

    Lam, Tony N.T.; Wan, Kevin K.W.; Wong, S.L.; Lam, Joseph C.

    2010-01-01

    Past and future trend of electricity use for air conditioning in the entire commercial sector in subtropical climates using 1979-2008 measured meteorological data as well as predictions for 2009-2100 from a general circulation model (MIROC3.2-H) was investigated. Air conditioning consumption showed an increasing trend over the past 30 years from 1979 to 2008. Principal component analysis (PCA) of measured and predicted monthly mean dry-bulb temperature, wet-bulb temperature and global solar radiation was conducted to determine a new climatic index Z for 1979-2008 and future 92 years (2009-2100) based on two emissions scenarios B1 and A1B (low and medium forcing). Through regression analysis, electricity use in air conditioning for the 92-year period was estimated. For low forcing, average consumption in 2009-2038, 2039-2068 and 2069-2100 would be, respectively, 5.7%, 12.8% and 18.4% more than the 1979-2008 average, with a mean 12.5% increase for the entire 92-year period. Medium forcing showed a similar increasing trend, but 1-4% more. Standard deviations of the monthly air conditioning consumption were found to be smaller suggesting possible reduction in seasonal variations in future years.

  11. The Evaluation of Unitary & Central Type Air-Conditioning Systems in Selected Florida Schools.

    Science.gov (United States)

    Bradley, William B.

    The study reported here was conducted in an effort to obtain data for comparing the combined owning and operating costs of two different types of air-conditioning systems in two elementary schools. Both schools were built during 1969-70 in the same geographical area along the southeast coast of Florida and are also served by the same electric…

  12. Experimental Study on Intelligent Control Scheme for Fan Coil Air-Conditioning System

    Directory of Open Access Journals (Sweden)

    Yanfeng Li

    2013-01-01

    Full Text Available An intelligent control scheme for fan coil air-conditioning systems has been put forward in order to overcome the shortcomings of the traditional proportion-integral-derivative (PID control scheme. These shortcomings include the inability of anti-interference and large inertia. An intelligent control test rig of fan coil air-conditioning system has been built, and MATLAB/Simulink dynamics simulation software has been adopted to implement the intelligent control scheme. A software for data exchange has been developed to combine the intelligence control system and the building automation (BA system. Experimental tests have been conducted to investigate the effectiveness of different control schemes including the traditional PID control, fuzzy control, and fuzzy-PID control for fan coil air-conditioning system. The effects of control schemes have been compared and analyzed in robustness, static and dynamic character, and economy. The results have shown that the developed data exchange interface software can induce the intelligent control scheme of the BA system more effectively. Among the proposed control strategies, fuzzy-PID control scheme which has the advantages of both traditional PID and fuzzy schemes is the optimal control scheme for the fan coil air-conditioning system.

  13. V-TECS Guide for Automobile Air Conditioning and Electrical System Technician.

    Science.gov (United States)

    Meyer, Calvin F.; Benson, Robert T.

    This curriculum guide provides an outline for an eight-unit course to train automobile air conditioning and electrical system technicians. Each unit focuses on a duty that is composed of a number of performance objectives. For each objective, these materials are provided: a task, a standard of performance of task, source of standard, conditions…

  14. Exploring policy strategies for mitigating HFC emissions from refrigeration and air conditioning

    NARCIS (Netherlands)

    Hekkenberg, M.; Uiterkamp, Anton J. M. Schoot

    The growing demand for cooling throughout the world, possibly increased by global climate change, requires the implementation of policies to mitigate the related greenhouse gas (GHG) emissions from energy and refrigerant use in the refrigeration and air conditioning (RAC) sector. This article aims

  15. Colonization by Cladosporium spp. of painted metal surfaces associated with heating and air conditioning systems

    Science.gov (United States)

    Ahearn, D. G.; Simmons, R. B.; Switzer, K. F.; Ajello, L.; Pierson, D. L.

    1991-01-01

    Cladosporium cladosporioides and C. hebarum colonized painted metal surfaces of covering panels and register vents of heating, air conditioning and ventilation systems. Hyphae penetrated the paint film and developed characteristic conidiophores and conidia. The colonies were tightly appressed to the metal surface and conidia were not readily detectable via standard air sampling procedures.

  16. Experimental investigation of a novel configuration of desiccant based evaporative air conditioning system

    International Nuclear Information System (INIS)

    Uçkan, İrfan; Yılmaz, Tuncay; Hürdoğan, Ertaç; Büyükalaca, Orhan

    2013-01-01

    Highlights: ► A novel desiccant based evaporative cooling system is developed and tested. ► Cooling capacity, COP and energy consumption of the system are evaluated. ► Indoor air conditions are in the range of thermal comfort zone and expanded comfort zone. ► Designing of the system have considerable effect on the energy consumption. - Abstract: A novel configuration of desiccant based evaporative cooling system for air conditioning application is developed and tested. At the beginning of the design stage of the system, an analysis is carried out in order to maximize the performance of the system. It is found based on configuration that outdoor air must be used for regeneration to increase performance of the system and so three air channels are used. Experiments are carried out to investigate the total performance of the system and performance of the components used during summer season in a hot and humid climate. Effectiveness values for both heat exchangers and evaporative coolers are calculated through this work. In addition to the cooling capacity, coefficient of performance (COP) and energy consumption of the system are also evaluated. Results show that the effectiveness for the heat exchangers and evaporative coolers are very high under different outdoor conditions. It is also shown from the results that indoor air conditions are in the range of thermal comfort zone defined by ASHRAE and expanded comfort zone for evaporative air conditioning applications.

  17. An energy performance assessment for indoor environmental quality (IEQ) acceptance in air-conditioned offices

    International Nuclear Information System (INIS)

    Wong, L.T.; Mui, K.W.

    2009-01-01

    Maintaining an acceptable indoor environmental quality (IEQ) for air-conditioned office buildings consumes a considerable amount of thermal energy. This study correlates thermal energy consumption with the overall occupant acceptance of IEQ in some air-conditioned offices. An empirical expression of an IEQ index associated with thermal comfort, indoor air quality, aural and visual comfort is used to benchmark the offices. Employing input parameters obtained from the building stocks of Hong Kong, the office portfolios regarding the thermal energy consumption and the IEQ index are determined by Monte Carlo simulations. In particular, an energy-to-acceptance ratio and an energy-to-IEQ improvement ratio are proposed to measure the performance of energy consumption for the IEQ in the air-conditioned offices. The ratios give the thermal energy consumption corresponding to a desirable percentage of IEQ acceptances and to an IEQ upgrade, respectively. The results showed a non-linear increasing trend of annual thermal energy consumption for IEQ improvement at the offices of higher IEQ benchmarks. The thermal energy consumption for visual comfort and indoor air quality would also be significant in these offices. This study provides useful information that incorporates the IEQ in air-conditioned offices into the development of performance evaluation measures for thermal energy consumption.

  18. HFC perspectives in air-conditioning and refrigeration; Perspectives HFC en A/C et refrigeration

    Energy Technology Data Exchange (ETDEWEB)

    Fauvarque, P. [ELF Atochem, Centre d`Application de Lavallois, 92 (France)

    1997-12-31

    This paper is a series of transparencies dealing with the development of substitutes for the replacement of the R-22 refrigerant in air-conditioning systems (R-134a, R-407C, R-410A), and in industrial refrigeration systems of agriculture and food industry (R-134a and R-404A). (J.S.)

  19. Thermal conditions and perceived air quality in an air-conditioned auditorium

    Science.gov (United States)

    Polednik, Bernard; Guz, Łukasz; Skwarczyński, Mariusz; Dudzińska, Marzenna R.

    2016-07-01

    The study reports measurements of indoor air temperature (T) and relative humidity (RH), perceived air quality (PAQ) and CO2, fine aerosol particle number (PN) and mass (PM1) concentrations in an air conditioned auditorium. The measurements of these air physical parameters have been carried out in the unoccupied auditorium with the air conditioning system switched off (AC off mode) and in the unoccupied and occupied auditorium with the air conditioning system switched off during the night and switched on during the day (AC on/off mode). The average indoor air thermal parameters, CO2 concentration and the PAQ value (in decipols) were elevated, while average PM1 concentration was lower in the AC on/off mode. A statistically significant (p PAQ values and CO2 concentrations (r = 0.66 and r = 0.59, respectively) in that AC mode. A significant negative correlation has been observed between T and PN and PM1 concentrations (r = -0.38 and r = -0.49, respectively). In the AC off mode the above relations between T and the particle concentrations were not that unequivocal. These findings may be of importance as they indicate that in certain AC operation modes the indoor air quality deteriorates along with the variation of the indoor air microclimate and room occupation. This, in turn, may adversely affect the comfort and productivity of the users of air conditioned premises.

  20. Human requirements in future air-conditioned environments: a search for excellence

    DEFF Research Database (Denmark)

    Fanger, Povl Ole

    2000-01-01

    Although air-conditioning has played a positive role for economic development in warm climates, its image is globally mixed. Field studies demonstrate that there are substantial numbers of dissatisfied people in many buildings, among them those suffering from SBS symptoms, even though existing...

  1. 2016 German refrigeration and air conditioning meeting. Proceedings; Deutsche Kaelte- und Klimatagung 2016. Tagungsbericht

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2016-07-01

    The following topics were dealt with: Large cryogenic facilities, relief valves, liquid helium, liquid-nitrogen and liquid hydrogen cooling, new concepts, foundations and materials of the heat-pump techniques, evaporation, phase-change materials, absorption, afterheat usage, ionic liquids, sorption, condensers, heat exchangers, back-cooling systems, refrigerants, caron dioxide, mobile applications, efficiency and optimization, air conditioning.

  2. Subsurface Thermal Energy Storage for Improved Heating and Air Conditioning Efficiency

    Science.gov (United States)

    2016-11-21

    through water evaporation , although some cooling also occurs due to sensible heat transfer . Cooling towers are very effective heat transfer devices... evaporator coil connected to the building heating , ventilation, and air conditioning (HVAC) system. The refrigerant evaporates in the coil, removing...vapor is directed to a condensing coil, where the refrigerant vapor condenses back into a liquid, releasing its heat of vaporization. During

  3. Principles of Refrigeration. Automotive Mechanics. Air Conditioning. Instructor's Guide [and] Student Guide.

    Science.gov (United States)

    Spignesi, B.

    This instructional package, one in a series of individualized instructional units on automobile air conditioning, consists of a student guide and an instructor guide dealing with the principles of refrigeration. Covered in the module are defining the term heat, defining the term British Thermal Unit (BTU), defining the term latent heat, listing…

  4. Anti-seismic air condition's cooling capability increase of the second control area

    International Nuclear Information System (INIS)

    Pan Qiang

    2008-01-01

    Secondary area (SCA) air-conditioning system is an important ventilation system in plant. It should achieve the indoor temperature controllable. To resolve the problem of cooling capacity insufficiency, on the basis of ventilation and refrigeration theory, the thesis analyzes the design modification plan. (author)

  5. Introduction to Heating, Ventilation and Air Conditioning (HVAC). Instructor Edition. Introduction to Construction Series.

    Science.gov (United States)

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This instructor's guide contains the materials required to teach a competency-based introductory course in heating, ventilating, and air conditioning (HVAC) to students who have chosen to explore careers in construction. It contains three units: HVAC materials, HVAC tools, and applied skills. Each instructional unit includes some or all of the…

  6. Introduction to Heating, Ventilation and Air Conditioning (HVAC). Introduction to Construction Series. Instructor Edition.

    Science.gov (United States)

    Associated General Contractors of America, Washington, DC.

    This module on introductory heating, ventilating, and air conditioning (HVAC) is one of a series of modules designed to teach basic skills necessary for entry-level employment in this field. The module contains four instructional units that cover the following topics: (1) HVAC materials; (2) HVAC tools; (3) HVAC layout; and (4) HVAC basic skills.…

  7. Proceedings of the 1993 non-fluorocarbon insulation, refrigeration and air conditioning technology workshop

    Energy Technology Data Exchange (ETDEWEB)

    1994-09-01

    Sessions included: HFC blown polyurethanes, carbon dioxide blown foam and extruded polystyrenes, plastic foam insulations, evacuated panel insulation, refrigeration and air conditioning, absorption and adsorption and stirling cycle refrigeration, innovative cooling technologies, and natural refrigerants. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

  8. Compensation of flow maldistribution in fin-and-tube evaporators for residential air-conditioning

    DEFF Research Database (Denmark)

    Kærn, Martin Ryhl; Brix, Wiebke; Elmegaard, Brian

    2011-01-01

    Compensation of flow maldistribution in multi-channel fin-and-tube evaporators for residential air-conditioning is investigated by numerical modeling. The considered sources of maldistribution are distribution of the liquid and vapor phases in the distributor and non-uniform airflow distribution....

  9. Exercise Equipment: Neutral Buoyancy

    Science.gov (United States)

    Shackelford, Linda; Valle, Paul

    2016-01-01

    Load Bearing Equipment for Neutral Buoyancy (LBE-NB) is an exercise frame that holds two exercising subjects in position as they apply counter forces to each other for lower extremity and spine loading resistance exercises. Resistance exercise prevents bone loss on ISS, but the ISS equipment is too massive for use in exploration craft. Integrating the human into the load directing, load generating, and motion control functions of the exercise equipment generates safe exercise loads with less equipment mass and volume.

  10. Using Hydrated Salt Phase Change Materials for Residential Air Conditioning Peak Demand Reduction and Energy Conservation in Coastal and Transitional Climates in the State of California

    Science.gov (United States)

    Lee, Kyoung Ok

    The recent rapid economic and population growth in the State of California have led to a significant increase in air conditioning use, especially in areas of the State with coastal and transitional climates. This fact makes that the electric peak demand be dominated by air conditioning use of residential buildings in the summer time. This extra peak demand caused by the use of air conditioning equipment lasts only a few days out of the year. As a result, unavoidable power outages have occurred when electric supply could not keep up with such electric demand. This thesis proposed a possible solution to this problem by using building thermal mass via phase change materials to reduce peak air conditioning demand loads. This proposed solution was tested via a new wall called Phase Change Frame Wall (PCFW). The PCFW is a typical residential frame wall in which Phase Change Materials (PCMs) were integrated to add thermal mass. The thermal performance of the PCFWs was first evaluated, experimentally, in two test houses, built for this purpose, located in Lawrence, KS and then via computer simulations of residential buildings located in coastal and transitional climates in California. In this thesis, a hydrated salt PCM was used, which was added in concentrations of 10% and 20% by weight of the interior sheathing of the walls. Based on the experimental results, under Lawrence, KS weather, the PCFWs at 10% and 20% of PCM concentrations reduced the peak heat transfer rates by 27.0% and 27.3%, on average, of all four walls, respectively. Simulated results using California climate data indicated that PCFWs would reduce peak heat transfer rates by 8% and 19% at 10% PCM concentration and 12.2% and 27% at 20% PCM concentration for the coastal and transitional climates, respectively. Furthermore, the PCFWs, at 10% PCM concentration, would reduce the space cooling load and the annual energy consumption by 10.4% and 7.2%, on average in both climates, respectively.

  11. Energy Performance and Optimal Control of Air-conditioned Buildings Integrated with Phase Change Materials

    Science.gov (United States)

    Zhu, Na

    This thesis presents an overview of the previous research work on dynamic characteristics and energy performance of buildings due to the integration of PCMs. The research work on dynamic characteristics and energy performance of buildings using PCMs both with and without air-conditioning is reviewed. Since the particular interest in using PCMs for free cooling and peak load shifting, specific research efforts on both subjects are reviewed separately. A simplified physical dynamic model of building structures integrated with SSPCM (shaped-stabilized phase change material) is developed and validated in this study. The simplified physical model represents the wall by 3 resistances and 2 capacitances and the PCM layer by 4 resistances and 2 capacitances respectively while the key issue is the parameter identification of the model. This thesis also presents the studies on the thermodynamic characteristics of buildings enhanced by PCM and on the investigation of the impacts of PCM on the building cooling load and peak cooling demand at different climates and seasons as well as the optimal operation and control strategies to reduce the energy consumption and energy cost by reducing the air-conditioning energy consumption and peak load. An office building floor with typical variable air volume (VAV) air-conditioning system is used and simulated as the reference building in the comparison study. The envelopes of the studied building are further enhanced by integrating the PCM layers. The building system is tested in two selected cities of typical climates in China including Hong Kong and Beijing. The cold charge and discharge processes, the operation and control strategies of night ventilation and the air temperature set-point reset strategy for minimizing the energy consumption and electricity cost are studied. This thesis presents the simulation test platform, the test results on the cold storage and discharge processes, the air-conditioning energy consumption and demand

  12. Energy savings potential of a hybrid desiccant dehumidification air conditioning system in Beirut

    International Nuclear Information System (INIS)

    Ghali, Kamel

    2008-01-01

    In this work, the transient performance of a hybrid desiccant vapor compression air conditioning system is numerically simulated for the ambient conditions of Beirut. The main feature of this hybrid system is that the regenerative heat needed by the desiccant wheel is partly supplied by the condenser dissipated heat while the rest is supplied by an auxiliary gas heater. The hybrid air conditioning system of the present study replaces a 23 kW vapor compression unit for a typical office in Beirut characterized by a high latent load. The vapor compression subsystem size in the hybrid air conditioning system is reduced to 15 kW at the peak load when the regeneration temperature was fixed at 75 deg. C. Also the sensible heat ratio of the combined hybrid system increased from 0.47 to 0.73. Based on hour by hour simulation studies for a wide range of recorded ambient conditions of Beirut city, this paper predicts the annual energy consumption of the hybrid system in comparison with the conventional vapor compression system for the entire cooling season. The annual running costs savings for the hybrid system is 418.39 USD for a gas cost price of 0.141 USD/kg. The pay back period of the hybrid system is less than five years when the initial cost of the hybrid air conditioning system priced an additional 1712.00 USD. Hence, for a 20-year life cycle, the life cycle savings of the hybrid air conditioning system are 4295.19 USD

  13. Heavy metal contamination in an urban stream fed by contaminated air-conditioning and stormwater discharges.

    Science.gov (United States)

    O'Sullivan, Aisling; Wicke, Daniel; Cochrane, Tom

    2012-03-01

    Urban waterways are impacted by diffuse stormwater runoff, yet other discharges can unintentionally contaminate them. The Okeover stream in Christchurch, New Zealand, receives air-conditioning discharge, while its ephemeral reach relies on untreated stormwater flow. Despite rehabilitation efforts, the ecosystem is still highly disturbed. It was assumed that stormwater was the sole contamination source to the stream although water quality data were sparse. We therefore investigated its water and sediment quality and compared the data with appropriate ecotoxicological thresholds from all water sources. Concentrations of metals (Zn, Cu and Pb) in stream baseflow, stormwater runoff, air-conditioning discharge and stream-bed sediments were quantified along with flow regimes to ascertain annual contaminant loads. Metals were analysed by ICP-MS following accredited techniques. Zn, Cu and Pb concentrations from stormflow exceeded relevant guidelines for the protection of 90% of aquatic species by 18-, 9- and 5-fold, respectively, suggesting substantial ecotoxicity potential. Sporadic copper (Cu) inputs from roof runoff exceeded these levels up to 3,200-fold at >4,000 μg L⁻¹ while Cu in baseflow from air-conditioning inputs exceeded them 5.4-fold. There was an 11-fold greater annual Cu load to the stream from air-conditioning discharge compared to stormwater runoff. Most Zn and Cu were dissolved species possibly enhancing metal bioavailability. Elevated metal concentrations were also found throughout the stream sediments. Environmental investigations revealed unsuspected contamination from air-conditioning discharge that contributed greater Cu annual loads to an urban stream compared to stormwater inputs. This discovery helped reassess treatment strategies for regaining ecological integrity in the ecosystem.

  14. Analisa Performansi Sistem Air Conditioning Mobil tipe ET 450 dengan Variasi Tekanan Kerja Kompresor

    Directory of Open Access Journals (Sweden)

    Adi Purnawan

    2012-11-01

    Full Text Available Comfort and coolness when traveling by vehicle especially car is highly needed. So many attempts have been made byhumans that comfortable traveling by car can be achieved. One of the effective ways in which comfortable traveling by car can beobtained is by installing air conditioning. The performance of air conditioning system is highly influenced by how the compressorworks. In other words, the pressure resulting from the suction highly determines the performance of air conditioning system,which then affects how the compressor works, the compressor power, the refrigeration effect, the efficiency of isentropic andcoefficient of performance (COP of the car air conditioning sytem especially that of the car air conditioner type ET 450. Fromwhat has been described above, the writer would like to conduct a research entiled “ Analysis of the Performance of the Car AirConditioning system Type ET 450 with Variation of the Compressor Pressure”.The test was conducted on the car air conditioner type ET 450 with variations of suction 2.8 bar, 3 bar, 3.2 bar, 3.4bar, 3.6 bar and 3.8 bar. The data were obtained from the pressure of compressor output (P2, the temperatures in each point areT1, T2, T3, T4, the compressor rotationn is n, the strength of electrical current is I, and the volumetric flow rate. The data werethen processed and analyzed so that so that the performance of each variation of the suction could be actually and theoreticallyobtained.The findings show that the bigger the suction, the bigger the performance of the car air conditioner type ET 450 wouldbe. The theoretical coefficient of performance (COP produced was bigger than the actual COP. The optimal COP took placewhen the suction was 441.325 kPa, the actual COP was 3.513177 and the theoretical COP was 3.632062

  15. [Biological contamination in office buildings related to ventilation/air conditioning system].

    Science.gov (United States)

    Bródka, Karolina; Sowiak, Małgorzata; Kozajda, Anna; Cyprowski, Marcin; Irena, Szadkowska-Stańczyk

    2012-01-01

    Indoor air is contaminated with microorganisms coming from both the atmospheric air and sources present in premises. The aim of this study was to analyze the concentrations of biological agents in office buildings, dependending on ventilation/air conditioning system and season. The study covered office buildings (different in the system of ventila-tion/air conditioning). Air samples for assessing the levels of inhalable dust, endotoxins and (1-->3)-beta-D-glucans, were taken at the selected stationary points of each building during summer and winter. The air was sampled for 6 h, using portable sets consisting of the GilAir 5 pump and the head filled with a filter of fiber glass. The samples for the presence of airborne bacteria and fungi were collected twice during the day using the impaction method. Average concentrations of inhalable dust, bacteria, fungi, endotoxins and (1-->3)-beta-D-glucans in office premises were 0.09 mg/m3, 6.00 x 10(2) cfu/m3, 4.59 x 10(1) cfu/m3, 0.42 ng/m3 and 3.91 ng/m3, respectively. Higher concentrations of the investigated agents were found in summer. In premises with air conditioning concentrations of airborne fungi, (1-->3)-beta-D-glucans and inhalable dust were significantly lower in winter. In summer the trend was reverse except for (1-->3)-beta-D-glucans. Concentrations of biological agents were affected by the season and the presence of air conditioning. Concentrations of inhalable dust, bacteria, fungi, endotoxins and (1-->3)-beta-D-glucans, observed inside the office buildings, were significantly higher in summer than in winter. The presence of the air conditioning system modified in various ways the levels of biological agents. Its influence was greater on the concentration of fungi and (1-->3)-beta-D-glucans than on that of bacteria and endotoxins.

  16. Air-conditioning Australian households: The impact of dynamic peak pricing

    International Nuclear Information System (INIS)

    Strengers, Yolande

    2010-01-01

    International mandates for smart metering are enabling variable and real-time pricing regimes such as dynamic peak pricing (DPP), which charges 10-40 times the off-peak rate for electricity during short periods. This regime aims to reduce peak electricity demand (predominantly due to increase in residential air-conditioning usage) and curb greenhouse gas emissions. Although trials indicate that DPP can achieve significant demand reductions, particularly in summer, little is known about how or why households change their cooling practices in response to this strategy. This paper discusses the outcomes of a small qualitative study assessing the impact of a DPP trial on household cooling practices in the Australian state of New South Wales. The study challenges common assumptions about the necessity of air-conditioning and impact of price signals. It finds that DPP engages households as co-managers of their cooling practices through a series of notification signals (SMS, phone, in-home display, email, etc.). Further, by linking the price signal to air-conditioning, some householders consider this practice discretionary for short periods of time. The paper concludes by warning that policy makers and utilities may serve to legitimise air-conditioning usage and/or negate demand reductions by failing to acknowledge the non-rational dynamics of DPP and household cooling practices. - Research highlights: →Most householders consider air-conditioning discretionary during DPP events →DPP engages householders as co-managers of their demand →Notification of an upcoming DPP event is significant to the response →Householders feel obligated to respond to DPP for a range of non-financial reasons

  17. Air-conditioning and antibiotics: Demand management insights from problematic health and household cooling practices

    International Nuclear Information System (INIS)

    Nicholls, Larissa; Strengers, Yolande

    2014-01-01

    Air-conditioners and antibiotics are two technologies that have both been traditionally framed around individual health and comfort needs, despite aspects of their use contributing to social health problems. The imprudent use of antibiotics is threatening the capacity of the healthcare system internationally. Similarly, in Australia the increasing reliance on air-conditioning to maintain thermal comfort is contributing to rising peak demand and electricity prices, and is placing an inequitable health and financial burden on vulnerable heat-stressed households. This paper analyses policy responses to these problems through the lens of social practice theory. In the health sector, campaigns are attempting to emphasise the social health implications of antibiotic use. In considering this approach in relation to the problem of air-conditioned cooling and how to change the ways in which people keep cool during peak times, our analysis draws on interviews with 80 Australian households. We find that the problem of peak electricity demand may be reduced through attention to the social health implications of air-conditioned cooling on very hot days. We conclude that social practice theory offers a fruitful analytical route for identifying new avenues for research and informing policy responses to emerging health and environmental problems. - Highlights: • Over-use of antibiotics and air-conditioning has social health implications. • Focusing on financial incentives limits the potential of demand management programs. • Explaining peak demand to households shifts the meanings of cooling practices. • Emphasising the social health implications of antibiotics and air-conditioning may resurrect alternative practices. • Analysing policy with social practice theory offers insights into policy approaches

  18. The 12 kV, 50 kA Pulse Generator for the SPS MKDH Horizontal Beam Dump Kicker System,equipped with Semiconductor Switches

    CERN Document Server

    Bonthond, J; Faure, P; Vossenberg, Eugène B; CERN. Geneva. SPS and LHC Division

    2001-01-01

    The high current pulses for the MKDH magnets are generated with capacitor discharge type generators which, combined with a resistive free-wheel diode circuit, deliver a critically damped half-sine current with a rise-time of 25 ms. Each generator consists of two 25 kA units, connected in parallel to a magnet via low inductance transmission lines. They are equipped with a stack of four Fast High Current Thyristors, together with snubber capacitors, a voltage divider and a specially designed trigger transformer.

  19. Development and Design of a User Interface for a Computer Automated Heating, Ventilation, and Air Conditioning System

    International Nuclear Information System (INIS)

    Anderson, B.

    1999-01-01

    A user interface is created to monitor and operate the heating, ventilation, and air conditioning system. The interface is networked to the system's programmable logic controller. The controller maintains automated control of the system. The user through the interface is able to see the status of the system and override or adjust the automatic control features. The interface is programmed to show digital readouts of system equipment as well as visual queues of system operational statuses. It also provides information for system design and component interaction. The interface is made easier to read by simple designs, color coordination, and graphics. Fermi National Accelerator Laboratory (Fermi lab) conducts high energy particle physics research. Part of this research involves collision experiments with protons, and anti-protons. These interactions are contained within one of two massive detectors along Fermilab's largest particle accelerator the Tevatron. The D-Zero Assembly Building houses one of these detectors. At this time detector systems are being upgraded for a second experiment run, titled Run II. Unlike the previous run, systems at D-Zero must be computer automated so operators do not have to continually monitor and adjust these systems during the run. Human intervention should only be necessary for system start up and shut down, and equipment failure. Part of this upgrade includes the heating, ventilation, and air conditioning system (HVAC system). The HVAC system is responsible for controlling two subsystems, the air temperatures of the D-Zero Assembly Building and associated collision hall, as well as six separate water systems used in the heating and cooling of the air and detector components. The BYAC system is automated by a programmable logic controller. In order to provide system monitoring and operator control a user interface is required. This paper will address methods and strategies used to design and implement an effective user interface

  20. 40 CFR Appendix B to Subpart B of... - Standard for Recover Equipment

    Science.gov (United States)

    2010-07-01

    ... protects the earth against harmful ultraviolet radiation. To reduce the emissions of CFCs, the 1990 Clean Air Act requires recycle of CFC-12 (R-12) used in mobile air-conditioning systems to eliminate system... reuse of CFCs in mobile air-conditioning systems. Establishing extraction equipment specifications for...

  1. Management of air-conditioning systems in residential buildings by using fuzzy logic

    Directory of Open Access Journals (Sweden)

    Sohair F. Rezeka

    2015-06-01

    Full Text Available There has been a rising concern in reducing the energy consumption in buildings. Heating, ventilation and air-conditioning system is the biggest consumer of energy in buildings. In this study, management of the air-conditioning system of a building for efficient energy operation and comfortable environment is investigated. The strategy used in this work depends on classifying the rooms to three different groups: very important rooms, important rooms and normal rooms. The total mass flow rate is divided between all rooms by certain percentage using a fuzzy-logic system to get the optimum performance for each room. The suggested Building Management System (BMS was found capable of keeping errors in both temperature and humidity within the acceptable limits at different operating conditions. The BMS can save the chilled/hot water flow rate and the cooling/heating capacity of rooms.

  2. Potential electricity savings by variable speed control of compressor for air conditioning systems

    Energy Technology Data Exchange (ETDEWEB)

    Nasution, Henry [Bung Hatta University, Department of Mechanical Engineering, Faculty of Industrial Engineering, Padang, West Sumatera (Indonesia); Wan Hassan, Mat Nawi [Universiti Teknologi Malaysia, Faculty of Mechanical Engineering, Skudai, Johor Bahru-Darul Ta' zim (Malaysia)

    2006-05-15

    The potential of a variable-speed compressor running on a controller to provide enhanced load-matching capability, energy saving and thermal comfort for application in air-conditioning system is demonstrated. An air-conditioning system, originally operated on a constant speed mode, is retrofitted with an inverter and a PID controller. The system was installed to a thermal environmental room together with a data acquisition system to monitor energy consumption and temperature of the room. Measurements were taken 2 h daily at a time interval of 5 min for an on/off and an inverter variable-speed conditions. The results indicate that thermal comfort of the room together with energy saving can be obtained through a proper selection of K for the controller. At a temperature setting of 22 C, the energy saving for the system is estimated to reach 25.3% for PID controllers. (orig.)

  3. Low-Flow Liquid Desiccant Air Conditioning: General Guidance and Site Considerations

    Energy Technology Data Exchange (ETDEWEB)

    Kozubal, E.; Herrmann, L.; Deru, M.; Clark, J.

    2014-09-01

    Dehumidification or latent cooling in buildings is an area of growing interest that has been identified as needing more research and improved technologies for higher performance. Heating, ventilating, and air-conditioning (HVAC) systems typically expend excessive energy by using overcool-and-reheat strategies to dehumidify buildings. These systems first overcool ventilation air to remove moisture and then reheat the air to meet comfort requirements. Another common strategy incorporates solid desiccant rotors that remove moisture from the air more efficiently; however, these systems increase fan energy consumption because of the high airside pressure drop of solid desiccant rotors and can add heat of absorption to the ventilation air. Alternatively, liquid desiccant air-conditioning (LDAC) technology provides an innovative dehumidification solution that: (1) eliminates the need for overcooling and reheating from traditional cooling systems; and (2) avoids the increased fan energy and air heating from solid desiccant rotor systems.

  4. Conceptual Design of Automotive Compressor for Integrated Portable Air Conditioning System

    Directory of Open Access Journals (Sweden)

    Ishak Muhammad Ikman

    2017-01-01

    Full Text Available This study introduces a new concept of portable air conditioner which integrated with some available components in automotive air conditioning system. This new idea intends to solve the storage problems as well as to reduce the price of current portable air conditioner since some devices could directly be used from the automotive air conditioning system. The primary emphasis of this study was on the modification of automotive compressor design so as the system may alternately be operated. The length of conventional compressor shaft is extended to place an additional clutch pulley, a drive plate and a clutch coil. The new concept particularly the shaft and pulley were analysed through slope deflection and computational finite element analyses. The result of engineering analyses exhibited that the new design of compressor shaft and clutch pulleys promote a low risk of failure as the data values recorded are lower than the critical value for each criterion investigated.

  5. Characterization of Francisella species isolated from the cooling water of an air conditioning system.

    Science.gov (United States)

    Gu, Quan; Li, Xunde; Qu, Pinghua; Hou, Shuiping; Li, Juntao; Atwill, Edward R; Chen, Shouyi

    2015-01-01

    Strains of Francisella spp. were isolated from cooling water from an air conditioning system in Guangzhou, China. These strains are Gram negative, coccobacilli, non-motile, oxidase negative, catalase negative, esterase and lipid esterase positive. In addition, these bacteria grow on cysteine-supplemented media at 20 °C to 40 °C with an optimal growth temperature of 30 °C. Analysis of 16S rRNA gene sequences revealed that these strains belong to the genus Francisella. Biochemical tests and phylogenetic and BLAST analyses of 16S rRNA, rpoB and sdhA genes indicated that one strain was very similar to Francisella philomiragia and that the other strains were identical or highly similar to the Francisella guangzhouensis sp. nov. strain 08HL01032 we previously described. Biochemical and molecular characteristics of these strains demonstrated that multiple Francisella species exist in air conditioning systems.

  6. Air conditioning system and component therefore distributing air flow from opposite directions

    Science.gov (United States)

    Obler, H. D.; Bauer, H. B. (Inventor)

    1974-01-01

    The air conditioning system comprises a plurality of separate air conditioning units coupled to a common supply duct such that air may be introduced into the supply duct in two opposite flow directions. A plurality of outlets such as registers or auxiliary or branch ducts communicate with the supply duct and valve means are disposed in the supply duct at at least some of the outlets for automatically channelling a controllable amount of air from the supply duct to the associated outlet regardless of the direction of air flow within the supply duct. The valve means comprises an automatic air volume control apparatus for distribution within the air supply duct into which air may be introduced from two opposite directions. The apparatus incorporates a freely swinging movable vane in the supply duct to automatically channel into the associated outlet only the deflected air flow which has the higher relative pressure.

  7. Badly maintained air conditioning installations (Part 2); Schlecht gewartete Klimaanlagen (Teil 2)

    Energy Technology Data Exchange (ETDEWEB)

    Haefliger, P. E.; Thies, U.

    2002-07-01

    This article is the second of a series of four articles that discuss hygiene problems that often occur in ventilation and air-conditioning installations. They describe the problems encountered in detail, provide the reader with appropriate know-how on hygiene-related topics and present an overview of the regulations appertaining to the problems along with inspection and analysis methods. In particular, this second article examines the so-called 'Sick Building Syndrome', its technical, chemical, biological and psychosocial causes and mentions the results of studies made in this area. Typical illnesses such as allergic alveolitis and legionnaires illness are discussed. Definitions of hygiene and comfort with respect to ventilation and air-conditioning installations are presented and problem areas such as filters, ducting, humidifiers and cooling are discussed. The article is rounded off - as are all articles of this series - with a comprehensive literature list.

  8. Applications and control of air conditioning systems using rapid cycling to modulate capacity

    Energy Technology Data Exchange (ETDEWEB)

    Poort, M.J.; Bullard, C.W. [Department of Mechanical and Industrial Engineering, Air Conditioning and Refrigeration Center, University of Illinois, 1206 W. Green St., Urbana, IL 61801 (United States)

    2006-08-15

    Rapid cycling the compressor of an air conditioning or refrigeration system can be used to modulate capacity, thus offering an alternative to a variable speed compressor. This paper explores design tradeoffs to optimize rapid cycling performance based on experimental results using two different evaporators and changing other components of an air conditioning system. Rapid cycling has inherent compressor lift penalties associated with larger mass flow rates, which need to be minimized. Preventing dryout (superheating) in the evaporator during the off cycle, a major penalty as cycles are lengthened, is also important. Evaporator dryout is minimized by increasing the refrigerant side area and reducing off cycle drainage. Combining a flash gas bypass with a suction line heat exchanger was found to maximize performance during the off cycle while allowing increased cycle lengths without incurring major penalties. (author)

  9. Investigating performance of microchannel evaporators for automobile air conditioning with different port structures

    Directory of Open Access Journals (Sweden)

    Guoliang Zhou

    2017-08-01

    Full Text Available Microchannel evaporator has been widely applied in automobile air conditioning, while it faces the problem of refrigerant maldistribution which deteriorates the thermal performance of evaporator. In this study, the performances of microchannel evaporators with different port structures are experimentally investigated for purpose of reducing evaporator pressure drop. Four evaporator samples with different port number and hydraulic diameter are made for this study. The performances of the evaporator samples are tested on a psychometric calorimeter test bench with the refrigerant R-134A at a real automobile air conditioning. The results on the variations of the evaporator pressure drop and evaporator surface temperature distribution are presented and analyzed. By studying the performance of an evaporator, seeking proper port structure is an approach to reduce refrigerant pressure drop as well as improve refrigerant distribution.

  10. Calculation of the Chilling Requirement for Air Conditioning in the Excavation Roadway

    Directory of Open Access Journals (Sweden)

    Yueping Qin

    2015-10-01

    Full Text Available To effectively improve the climate conditions of the excavation roadway in coal mine, the calculation of the chilling requirement taking air conditioning measures is extremely necessary. The temperature field of the surrounding rock with moving boundary in the excavation roadway was numerically simulated by using finite volume method. The unstable heat transfer coefficient between the surrounding rock and air flow was obtained via the previous calculation. According to the coupling effects of the air flow inside and outside air duct, the differential calculation mathematical model of air flow temperature in the excavation roadway was established. The chilling requirement was calculated with the selfdeveloped computer program for forecasting the required cooling capacity of the excavation roadway. A good air conditioning effect had been observed after applying the calculated results to field trial, which indicated that the prediction method and calculation procedure were reliable.

  11. Aspergillus prevalence in air conditioning filters from vehicles: taxis for patient transportation, forklifts, and personal vehicles.

    Science.gov (United States)

    Viegas, Carla; Moreira, Ricardo; Faria, Tiago; Caetano, Liliana Aranha; Carolino, Elisabete; Gomes, Anita Quintal; Viegas, Susana

    2018-05-04

    The frequency and importance of Aspergillus infections is increasing worldwide. This study aimed to assess the occupational exposure of forklifts and taxi drivers to Aspergillus spp. Nineteen filters from air conditioning system of taxis, 17 from forklifts and 37 from personal vehicles were assessed. Filters extract were streaked onto MEA, DG18 and in azole-supplemented media. Real-time quantitative PCR amplification of selected Aspergillus species-complex was also performed. Forklifts filter samples presented higher median values. Aspergillus section Nigri was the most observed in forklifts filters in MEA (28.2%) and in azole-supplemented media. DNA from Aspergillus sections Fumigati and Versicolores was successfully amplified by qPCR. This study enlightens the added value of using filters from the air conditioning system to assess Aspergillus spp. occupational exposure. Aspergillus azole resistance screening should be included in future occupational exposure assessments.

  12. 2011 German refrigeration and air conditioning meeting. Proceedings; Deutsche Kaelte-Klima-Tagung 2011. Tagungsbericht

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    Within the DKV conference of the Deutscher Kaelte- und Klimatechnischer Verein e.V. (Hanover, Federal Republic of Germany) from 16th to 18th November, 2011, at the Eurogress Aachen (Federal Republic of Germany) 112 lectures were held according to the following themes: cryomedicine, cryobiology, cryocomponents, mobility, cryoapplications, miniature cooler, Fundamentals and materials in the cryotechnology and heat pump technology, heat transfer, absorption processes, materials characteristics and phase change materials, storage and phase change, plants and components of refrigerating and heat pump technology - compressors, control and systems, energy efficiency (and CO{sub 2}), standardization and standard, application of refrigeration, supermarket/coolant, enhancement of efficiency in the air conditioning of passenger cars, indoor air conditioning in automobiles, enhancement of efficiency in different vehicles, climate technology and application of heat pumps - field tests and optimization, test rigs and simulations, heat pumps, optimisation in new buildings and stock buildings, climate coolants and quality of air. Beside this conference twelve student meetings were presented.

  13. Modeling of an Air Conditioning System with Geothermal Heat Pump for a Residential Building

    Directory of Open Access Journals (Sweden)

    Silvia Cocchi

    2013-01-01

    Full Text Available The need to address climate change caused by greenhouse gas emissions attaches great importance to research aimed at using renewable energy. Geothermal energy is an interesting alternative concerning the production of energy for air conditioning of buildings (heating and cooling, through the use of geothermal heat pumps. In this work a model has been developed in order to simulate an air conditioning system with geothermal heat pump. A ground source heat pump (GSHP uses the shallow ground as a source of heat, thus taking advantage of its seasonally moderate temperatures. GSHP must be coupled with geothermal exchangers. The model leads to design optimization of geothermal heat exchangers and to verify the operation of the geothermal plant.

  14. 2013 German refrigeration and air conditioning meeting. Proceedings; Deutsche Kaelte- und Klimatagung 2013. Tagungsbericht

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-07-01

    These proceedings cover the following main topics: cryoengineering - superconduction / energy storage; cryoapplications in biology and medicine; metrology; adsorption processes; condensation/evaporation; working fluids / simulation; ice production; plants and compressors; expansion and ejectors or recooling; use of cooling (passenger car air conditioning, supermarket); refrigerants; plant efficiency; emissions and legislation; air conditioning and use of heat pumps; air quality and control; building technology and block-type thermal power stations. [German] Dieser Tagungsbericht enthaelt folgende Themenschwerpunkte: Kryotechnik - Supraleitung/Energiespeicher; Kryoanwendungen in der Biologie und Medizin; Messtechnik; Adsorptionsprozesse; Kondensation/Verdampfung; Arbeitsfluide/Simulation; Eiserzeugung; Anlagen und Verdichter; Expansion und Ejektoren bzw. Rueckkuehlung; Kaelteanwendung (PKW-Klimatisierung; Supermarkt); Kaeltemittel; Anlageneffizienz; Emissionen und Gesetzgebung; Klimatechnik und Waermepumpenanwendung; Luftqualitaet und Regelung; Gebaeudetechnik und BHKW.

  15. Electricity savings ``soon come'' to Jamaica -- Assessing the potential for air conditioning and refrigeration end-use DSM

    Energy Technology Data Exchange (ETDEWEB)

    Conlon, T.; Hamzawi, E.; Campbell, V.

    1998-07-01

    With the support of the Inter-American Development Bank, the Global Environment Facility of the World Bank, and the Rockefeller Foundation, the national electric utility in Jamaica (Jamaica Public Service Company) has begun an assessment of the technical, economic, and financial opportunities for achieving demand-side management (DSM) energy savings in the air conditioning and refrigeration end uses. The feasibility and cost effectiveness of specific measures is being assessed for both the residential and commercials segments. While structures as a traditional load-research-based market assessment, the project uses ethnographic data collection and analysis techniques and involves collaboration with local contractors. The skills of local experts are being taped to identify and interview the key market players, and to develop an understanding of the barriers to and opportunities for energy efficiency present in the evolving equipment markets. The paper outlines methods and presents preliminary case study results for the air conditioning market. The authors identify major groups of market players and dominant types of equipment, and provide an overview of market dynamics. The volume of sales passing through both formal and informal distribution channels is estimated and market barriers are identified. Based on the findings of the study, recommendations will be made for future program and policy initiatives designed to mitigate selected barriers in each of the supply chains.

  16. THERMAL COMFORT STUDY OF AN AIR-CONDITIONED DESIGN STUDIO IN TROPICAL SURABAYA

    OpenAIRE

    Agus Dwi Hariyanto

    2005-01-01

    This paper evaluates the current thermal comfort condition in an air-conditioned design studio using objective measurement and subjective assessment. Objective measurement is mainly to quantify the air temperature, MRT, relative humidity, and air velocity. Subjective assessment is conducted using a questionnaire to determine the occupants thermal comfort sensations and investigate their perception of the thermal comfort level. A design studio in an academic institution in Surabaya was chosen ...

  17. Sustainability Challenges from Climate Change and Air Conditioning Use in Urban Areas

    OpenAIRE

    Lundgren, Karin; Kjellström, Tord

    2013-01-01

    Global climate change increases heat loads in urban areas causing health and productivity risks for millions of people. Inhabitants in tropical and subtropical urban areas are at especial risk due to high population density, already high temperatures, and temperature increases due to climate change. Air conditioning is growing rapidly, especially in South and South-East Asia due to income growth and the need to protect from high heat exposures. Studies have linked increased total hourly elect...

  18. Impaired Air Conditioning within the Nasal Cavity in Flat-Faced Homo.

    Directory of Open Access Journals (Sweden)

    Takeshi Nishimura

    2016-03-01

    Full Text Available We are flat-faced hominins with an external nose that protrudes from the face. This feature was derived in the genus Homo, along with facial flattening and reorientation to form a high nasal cavity. The nasal passage conditions the inhaled air in terms of temperature and humidity to match the conditions required in the lung, and its anatomical variation is believed to be evolutionarily sensitive to the ambient atmospheric conditions of a given habitat. In this study, we used computational fluid dynamics (CFD with three-dimensional topology models of the nasal passage under the same simulation conditions, to investigate air-conditioning performance in humans, chimpanzees, and macaques. The CFD simulation showed a horizontal straight flow of inhaled air in chimpanzees and macaques, contrasting with the upward and curved flow in humans. The inhaled air is conditioned poorly in humans compared with nonhuman primates. Virtual modifications to the human external nose topology, in which the nasal vestibule and valve are modified to resemble those of chimpanzees, change the airflow to be horizontal, but have little influence on the air-conditioning performance in humans. These findings suggest that morphological variation of the nasal passage topology was only weakly sensitive to the ambient atmosphere conditions; rather, the high nasal cavity in humans was formed simply by evolutionary facial reorganization in the divergence of Homo from the other hominin lineages, impairing the air-conditioning performance. Even though the inhaled air is not adjusted well within the nasal cavity in humans, it can be fully conditioned subsequently in the pharyngeal cavity, which is lengthened in the flat-faced Homo. Thus, the air-conditioning faculty in the nasal passages was probably impaired in early Homo members, although they have survived successfully under the fluctuating climate of the Plio-Pleistocene, and then they moved "Out of Africa" to explore the more

  19. Amelioration of Heat-Stress Conditions of Egyptian Summer Season on Friesian Calves Using Air Condition

    International Nuclear Information System (INIS)

    Nessim, M.Z.; Kamal, T.H.; Khalil, W.K.B.

    2010-01-01

    Male Friesian calves were used to evaluate cool air condition (AC) in alleviating heat stress (HS) determined by Heat Shock Protein genes expression (HSP), hormonal, biochemical and physiological parameters. The animals were exposed to summer heat stress (HS) under shade for two weeks (control). The maximum temperature humidity index (THI) during summer HS was from 81 to 88. Afterward the animals were exposed to AC, inside a climatic chamber for 6 hours daily for two weeks, where, the THI was from 70 to 71. The results revealed that expression level of the Hsp genes (Hsp72, Hsp70.1, Hsp70 and Hsp47) was lower under air condition treatment than under summer heat stress. Rectal temperature and respiration rate were significantly lower (p< 0.01) under air condition treatment than those under heat stress. Total triiodothyronin (T3) level was significantly higher (P< 0.05) in AC cooling treatments than in HS, while cortisol level was significantly lower (P < 0.01) in AC cooling treatment than in HS calves. Creatinine and Urea -N levels were significantly lower (P < 0.01) in AC cooling treatment than in HS calves. Triglycerides, ALT and AST levels were significantly lower (p<0.01), (P< 0.01) and (p<0.05), respectively in AC cooling treatment than in HS calves. These results demonstrated that there is a relationship between the molecular weight of HSPs and the level of HSPs gene exprisson. The higher the molecular weight (HSP 72) the lower is the HSPs gene expression level (0.82 in HS and 0.39 in AC) and vise versa. This holds true in both heat stress and air condition. AC treatment is capable to ameliorate heat stress of Friesian calves under hot summer climate

  20. Filters from taxis air conditioning system: A tool to characterize driver's occupational exposure to bioburden?

    Science.gov (United States)

    Viegas, Carla; Monteiro, Ana; Dos Santos, Mateus; Faria, Tiago; Caetano, Liliana Aranha; Carolino, Elisabete; Quintal Gomes, Anita; Marchand, Geneviève; Lacombe, Nancy; Viegas, Susana

    2018-07-01

    Bioburden proliferation in filters from air conditioning systems of taxis represents a possible source of occupational exposure. The aim of this study was to determine the occurrence of fungi and bacteria in filters from the air conditioning system of taxis used for patient transportation and to assess the exposure of drivers to bioburden. Filters from the air conditioning systems of 19 taxis and 28 personal vehicles (used as controls) operating in three Portuguese cities including the capital Lisbon, were collected during the winter season. The occurrence and significance of bioburden detected in the different vehicles are reported and discussed in terms of colony-forming units (CFU) per 1 m 2 of filter area and by the identification of the most frequently detected fungal isolates based on morphology. Azole-resistant mycobiota, fungal biomass, and molecular detection of Aspergillus species/strains were also determined. Bacterial growth was more prevalent in taxis (63.2%) than in personal vehicles (26.3%), whereas fungal growth was more prevalent in personal vehicles (53.6%) than in taxis (21.1-31.6%). Seven different azole-resistant species were identified in this study in 42.1% taxi filters. Levels of fungal biomass were above the detection limit in 63% taxi filters and in 75% personal vehicle filters. No toxigenic species were detected by molecular analysis in the assessed filters. The results obtained show that bioburden proliferation occurs widely in filters from the air conditioning systems of taxis, including the proliferation of azole-resistant fungal species, suggesting that filters should be replaced more frequently. The use of culture based-methods and molecular tools combined enabled an improved risk characterization in this setting. Copyright © 2018 Elsevier Inc. All rights reserved.

  1. Exergy analysis of a centralized air conditioning system for ice water

    International Nuclear Information System (INIS)

    Armas, Juan C; Lapido, Margarita J; Castellanos, Juan A

    2006-01-01

    An exergetic analysis of a centralized system of air conditioning, based on a vapor compression refrigeration cycle, appears in this article. The investigation allows to calculate the irreversibilities (exergy destruction) in the main components of the refrigeration cycle as well as to evaluate the sensitivity of this indicator when the operating conditions changes. As main result the most sensible components of the cycle are identified, information that will be useful in order to define strategies of operation focused to the power efficiency increase.

  2. Silver zeolite antimicrobial activity in aluminium heating, ventilation and air conditioning system ducts.

    Science.gov (United States)

    Rizzetto, R; Mansi, A; Panatto, D; Rizzitelli, E; Tinteri, C; Sasso, T; Gasparini, R; Crovari, P

    2008-03-01

    Air pollution in confined environments is a serious health problem, in that most people spend long periods indoors (in homes, offices, classrooms etc.). Some people (children, the elderly, heart disease patients, asthmatic or allergic subjects) are at greater risk because of their conditions of frailty. The growing use of air-conditioning systems in many public and private buildings aggravates this health risk, especially when these systems are not correctly installed or regularly serviced. The aim of our study was to verify the capacity of Ag+ ions to stop the growth of bacteria and moulds inside the ducts of Heating, Ventilation and Air Conditioning system ducts (HVAC) systems when these ducts were lined with active Ag+ ions zeolite-coated panels. A Y-shaped HVAC model with two branches was used; one branch was made of traditional galvanized iron, as was the whole system, while the other was lined with active Ag+ zeolite-coated polyurethane panels. During the test, samples of dust present inside both ducts were collected and seeded in liquid and solid media to detect bacteria and moulds. The presence of bacteria was also sought in the air emerging from the outlets of both ducts. Tests made on samples of particulate collected from the two different ducts revealed a lower total bacterial load in the samples collected from the Ag+ zeolite-coated duct than in the samples from the traditional Zn galvanized duct. In addition, the values of bacterial load found in the air emerging from the Ag+ ions zeolite-lined duct were 5 times lower than those found in the air from the traditional galvanized iron duct. The utilization of Ag+ zeolite-coated panels in air-conditioning systems could improve the quality of the emerging air in comparison with traditional installations in galvanized iron. This innovation could prove particularly advantageous in the event of accidents during the installation of air-conditioning systems or of contaminated aerosols coming from outside.

  3. An energy impact assessment of indoor air quality acceptance for air-conditioned offices

    International Nuclear Information System (INIS)

    Wong, L.T.; Mui, K.W.; Shi, K.L.; Hui, P.S.

    2008-01-01

    Treatment of fresh air in ventilation systems for the air-conditioning consumes a considerable amount of energy and affects the indoor air quality (IAQ). The ventilation demand is primarily related to the occupant load. In this study, the ventilation demands due to occupant load variations and occupant acceptability were examined against certain IAQ objectives using the mass balance of carbon dioxide (CO 2 ) concentrations in an air-conditioned office. In particular, this study proposed a ventilation model for the consideration of the occupant load variations and occupant acceptability based on the regional survey of typical offices (422 samples) in Hong Kong. The model was applied to evaluate the relative energy performance of different IAQ objectives in ventilation systems for typical office buildings in Hong Kong. The results showed that the energy consumption of a ventilation system would be correlated with the occupant load and acceptability in the air-conditioned office. Indicative CO 2 levels of 800 ppmv, 1000 ppmv and 1200 ppmv corresponding to 83%, 97% and 99.7% survey samples were shown, corresponding to the thermal energy consumptions of 1500 MJ m -2 yr -1 , 960 MJ m -2 yr -1 and 670 MJ m -2 yr -1 , respectively. In regards to the monetary issue, an annual value of HK$ 762 million per year in electrical consumption could be saved in all office buildings in Hong Kong when the indoor target CO 2 concentration is increased from 1000 ppmv to 1200 ppmv. To achieve an excellent IAQ following the existing design standard, i.e. to decrease the CO 2 level from 1000 ppmv to 800 ppmv, 56% additional energy would be consumed, corresponding to an annual value of HK$ 1,419 million, even though the occupant acceptability is only improved from 81% to 86%. The development of the models in this study would be useful for the energy performance evaluation of ventilation systems in air-conditioned offices

  4. Design and Simulation of an Air Conditioning Project in a Hospital Based on Computational Fluid Dynamics

    OpenAIRE

    Ding X. R.; Guo Y. Y.; Chen Y. Y.

    2017-01-01

    This study aims to design a novel air cleaning facility which conforms to the current situation in China, and moreover can satisfy our demand on air purification under the condition of poor air quality, as well as discuss the development means of a prototype product. Air conditions in the operating room of a hospital were measured as the research subject of this study. First, a suitable turbulence model and boundary conditions were selected and computational fluid dynamics (CFD) software was ...

  5. Experimental and numerical study of an evaporatively-cooled condenser of air-conditioning systems

    International Nuclear Information System (INIS)

    Islam, M.R.; Jahangeer, K.A.; Chua, K.J.

    2015-01-01

    The performance of an air-conditioning unit with evaporately-cooled condenser coil is studied experimentally and numerically. An experimental setup is fabricated by retrofitting a commercially available air-conditioning unit and installing comprehensive measuring sensors and controllers. Experimental result shows that the COP (Coefficient of Performance) of the evaporately-cooled air-conditioning unit increases by about 28% compared to the conventional air cooled air-conditioning unit. To analyze the heat and mass transfer processes involved in the evaporately-cooled condenser, a detailed theoretical model has been developed based on the fluid flow characteristics of the falling film and the thermodynamic aspect of the evaporation process. Simulated results agree well with experimental data. The numerical model provides new insights into the intrinsic links between operating variables and heat transfer characteristics of water film in evaluating the performance of evaporatively-cooled condenser system. Two heat transfer coefficients, namely, wall to bulk and bulk to interface are introduced and computed from the simulation results under different operating conditions. Finally, the overall heat transfer coefficient for the water film is computed and presented as a function of dimensionless variables which can conveniently be employed by engineers to design and analyze high performance evaporatively-cooled heat exchangers. - Highlights: • Performance of evaporatively-cooled condenser is investigated. • Local convective heat transfer coefficients of water film are determined. • Thermal resistance of water film is negligible. • Heat transfer with evaporated vapor plays significant role on performance. • Better condenser performance translates to an improvement in COP

  6. Enthalpy estimation for thermal comfort and energy saving in air conditioning system

    International Nuclear Information System (INIS)

    Chu, C.-M.; Jong, T.-L.

    2008-01-01

    The thermal comfort control of a room must consider not only the thermal comfort level but also energy saving. This paper proposes an enthalpy estimation that is conducive for thermal comfort control and energy saving. The least enthalpy estimator (LEE) combines the concept of human thermal comfort with the theory of enthalpy to predict the load for a suitable setting pair in order to maintain more precisely the thermal comfort level and save energy in the air conditioning system

  7. Thermal comfort in air-conditioned mosques in the dry desert climate

    Energy Technology Data Exchange (ETDEWEB)

    Al-ajmi, Farraj F. [Department of Civil Engineering, College of Technological Studies, Shuwaikh 70654 (Kuwait)

    2010-11-15

    In Kuwait, as in most countries with a typical dry desert climate, the summer season is long with a mean daily maximum temperature of 45 C. Centralized air-conditioning, which is generally deployed from the beginning of April to the end of October, can have tremendous impact on the amount of electrical energy utilized to mechanically control the internal environment in mosque buildings. The indoor air temperature settings for all types of air-conditioned buildings and mosque buildings in particular, are often calculated based on the analytical model of ASHRAE 55-2004 and ISO 7730. However, a field study was conducted in six air-conditioned mosque buildings during the summers of 2007 to investigate indoor climate and prayers thermal comfort in state of Kuwait. The paper presents statistical data about the indoor environmental conditions in Kuwait mosque buildings, together with an analysis of prayer thermal comfort sensations for a total of 140 subjects providing 140 sets of physical measurements and subjective questionnaires were used to collect data. Results show that the neutral temperature (T{sub n}) of the prayers is found to be 26.1 C, while that for PMV is 23.3 C. Discrepancy of these values is in fact about 2.8 C higher than those predicted by PMV model. Therefore, thermal comfort temperature in Kuwait cannot directly correlate with ISO 7730 and ASHRAE 55-2004 standards. Findings from this study should be considered when designing air conditioning for mosque buildings. This knowledge can contribute towards the development of future energy-related design codes for Kuwait. (author)

  8. 40 CFR 82.36 - Approved refrigerant handling equipment.

    Science.gov (United States)

    2010-07-01

    ... equipment. 82.36 Section 82.36 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) PROTECTION OF STRATOSPHERIC OZONE Servicing of Motor Vehicle Air Conditioners § 82.36...-12, Extraction and Recycle Equipment for Mobile Automotive Air-Conditioning Systems, and Standard of...

  9. Experimental study of a novel capacity control algorithm for a multi-evaporator air conditioning system

    International Nuclear Information System (INIS)

    Xu Xiangguo; Pan Yan; Deng Shiming; Xia Liang; Chan Mingyin

    2013-01-01

    The use of a multi-evaporator air conditioning (MEAC) system is advantageous in terms of installation convenience, high design flexibility, being easy to maintain and commission, better indoor thermal comfort control and higher energy efficiency. While MEAC units worth billions of dollars are sold worldwide, the detailed accounts on compressor capacity control and refrigeration flow distribution amongst evaporators remain unavailable in public domain, mainly due to commercial confidentiality. Limited control algorithms for MEAC systems have been developed based on system simulation, and no experimental-based capacity controller developments and their controllability tests may be identified in open literature. In the study reported in this paper, a novel capacity control algorithm, which imitated On–Off control of a single evaporator air conditioning (A/C) system in each indoor unit of a MEAC system by using variable speed compressor and electronic expansion valves (EEVs), was developed. Controllability tests under various settings for experimentally validating the novel capacity control algorithm were carried out and the control algorithm was further improved based on the experimental results. - Highlights: ► A capacity control algorithm for a multi-evaporator air conditioning system was developed. ► Experimental controllability tests under various settings were carried out. ► The control algorithm was further improved based on the experimental results.

  10. 'TEWI' concept for estimation of the global warming from the refrigerating and air conditioning systems

    International Nuclear Information System (INIS)

    Ciconkov, Risto

    2002-01-01

    The most applied CFC refrigerants and their HFC alternatives. values of ODP (Ozone Depletion Potential) and GWP (Global Warming Potential) of the most used refrigerants. natural working fluids and their properties. Montreal Protocol and Kyoto Protocol, illogical relations between them concerning to the HFC fluids. Confusion and polemics on the international level about the appliance of HFCs which, by the Kyoto Protocol, are liable to reduction. Introduction of the TEWI concept as a method for estimating the overall influence of refrigerating and air conditioning systems on the greenhouse effect: the direct emission (refrigerant leakage in the atmosphere) and indirect emission as a result of the electrical energy consumption. A demonstration of the TEWI concept on the concrete example in several variants. A discussion about the appliance of the TEWI concept. Meaning of the energy efficiency of the refrigerating systems (indirect CO 2 emission). One of the main measures: prevention of refrigerant leakage (direct CO 2 emission). A need of permanent education and training courses of the people who work on refrigerating and air conditioning systems. A necessity for constitution of an expert body in the country, preparation of a strategy to lay obligations on the new changes of the Kyoto Protocol and news on the world market. Introduction of country regulations, certification of the companies and people involved in refrigeration and air conditioning. (Author)

  11. Hospital-acquired infections associated with poor air quality in air-conditioned environments

    Directory of Open Access Journals (Sweden)

    Daniela Pinheiro da Silva

    2013-10-01

    Full Text Available Backgound and Objectives: Individuals living in cities increasingly spend more time indoors in air-conditioned environments. Air conditioner contamination can be caused by the presence of aerosols from the external or internal environment, which may be associated with disease manifestations in patients present in this type of environment. Therefore, the aim of this review was to assess the air quality in air-conditioned hospital environments as a risk factor for hospital-acquired infections – HAI – as the air can be a potential source of infection, as well as assess the exposure of professionals and patients to different pollutants. Material and Methods: A literature review was performed in the LILACS, MEDLINE, SCIELO, SCIENCE DIRECT databases, CAPES thesis database and Ministry of Health – Brazil, including studies published between 1982 and 2008. The literature search was grouped according to the thematic focus, as follows: ventilation, maintenance and cleaning of systems that comprehend the environmental quality standard. Discussion and Conclusion: Outbreaks of hospital-acquired infections associated with Aspergillus, Acinetobacter, Legionella, and other genera such as Clostridium and Nocardia, which were found in air conditioners, were observed, thus indicating the need for air-conditioning quality control in these environments.

  12. Energy and Greenhouse Gas Emission Assessment of Conventional and Solar Assisted Air Conditioning Systems

    Directory of Open Access Journals (Sweden)

    Xiaofeng Li

    2015-11-01

    Full Text Available Energy consumption in the buildings is responsible for 26% of Australia’s greenhouse gas emissions where cooling typically accounts for over 50% of the total building energy use. The aim of this study was to investigate the potential for reducing the cooling systems’ environmental footprint with applications of alternative renewable energy source. Three types of cooling systems, water cooled, air cooled and a hybrid solar-based air-conditioning system, with a total of six scenarios were designed in this work. The scenarios accounted for the types of power supply to the air-conditioning systems with electricity from the grid and with a solar power from highly integrated building photovoltaics (BIPV. Within and between these scenarios, systems’ energy performances were compared based on energy modelling while the harvesting potential of the renewable energy source was further predicted based on building’s detailed geometrical model. The results showed that renewable energy obtained via BIPV scenario could cover building’s annual electricity consumption for cooling and reduce 140 tonnes of greenhouse gas emissions each year. The hybrid solar air-conditioning system has higher energy efficiency than the air cooled chiller system but lower than the water cooled system.

  13. Assessment of indoor air quality in comparison using air conditioning and fan system in printing premise

    Directory of Open Access Journals (Sweden)

    Ramlan Nazirah

    2017-01-01

    Full Text Available Printers contribute to various emissions consist with chemical contaminants. High concentration of the particulate matter can cause serious health problems. This study focuses on the indoor air quality in printing premise unit in Universiti Tun Hussein Onn, Malaysia. Field testing involving air sampling methods were taken from 900 hours to 1600 hours, for every 30 minutes using physical measurement which is Multi-Channel Air Quality Monitor (YESAIR, E-Sampler and Ozone Meter. Air sampling was recorded based on one sampling point and most suitable point for production. A comparison based on different ventilation using fan and air-conditioning were also taken and results is being compared based on OSHA and NIOSH standards. Besides that, the statistical analysis is being conducted in order to predict the effect on number of printers. From the result, the O3 concentrations show, 10% reduced for printing premise using fan ventilation compared to air-conditioning but remain the same value for PM2.5. The concentration of O3 increased when the number of printers decreased, while the concentration of PM2.5 increased the increase of printers number. Overall, the use of fan in printing premise is more suggested since the level is slightly lower than the printing premise using air-conditioning.

  14. Possible schemes for solar-powered air-conditioning in 2-storey terrace houses

    International Nuclear Information System (INIS)

    Chu, C.M.; Bono, A.; Prabhakar, A.

    2006-01-01

    Space cooling is required all year round in the tropics, and probably accounts for a considerable proportion of the cost of electricity. Solar radiation can be channeled into cooling by photovoltaic powered systems and through the relatively new adsorption cycle technology. Two-storey terrace housing appear to have the greatest potential of introducing solar-powered cooling to residential homes. There are two schemes to cool a two-storey terrace housing: 1) By spraying water down the roof a tank, circulated by a pump powered by PV panels on the roof or 2) By replacing the roof with solar hot water collectors and use adsorption cooling chillers to produce air-conditioning for the entire block of terrace houses. In scheme number 1, a preliminary, rough technical evaluation showed that it is possible to pump water to the roof to flow down as a thin film and cool the roof by evaporation to about 40 degree C from about 70 degree C if without water evaporation at the highest insolation rate of the day. Scheme number 2, which uses adsorption chilling technology, requires communal sharing of the air-conditioning facility. The effect of collecting solar heat using the roof is two fold: to absorb solar energy for producing hot water and reducing excess heat input to the house. Preliminary costing demonstrates that solar-powered air-conditioning is within reach of commercialisation, bearing in mind that bulk purchases will dramatically lower the price of a product

  15. Research on ration selection of mixed absorbent solution for membrane air-conditioning system

    International Nuclear Information System (INIS)

    Li, Xiu-Wei; Zhang, Xiao-Song; Wang, Fang; Zhao, Xiao; Zhang, Zhuo

    2015-01-01

    Highlights: • We derive models of the membrane air-conditioning system with mixed absorbents. • We make analysis on system COP, cost-effectiveness and economy. • The paper provides a new method for ideal absorbent selection. • The solutes concentration of 50% achieves the best cost-effectiveness and the economy. - Abstract: Absorption air-conditioning system is a good alternative to vapor compression system for developing low carbon society. To improve the performance of the traditional absorption system, the membrane air-conditioning system is configured and its COP can reach as high as 6. Mixed absorbents are potential for cost reduction of the membrane system while maintaining a high COP. On the purpose of finding ideal mixed absorbent groups, this paper makes analysis on COP, cost-effectiveness and economy of the membrane system with mixed LiBr–CaCl 2 absorbent solution. The models of the system have been developed for the analysis. The results show the COP is higher for the absorbent groups with lower concentration of the total solute and higher concentration ratio of LiBr. It also reveals when the total solutes concentration is about 50%, it achieves the best cost-effectiveness and the economy. The process of the analysis provides a useful method for mixed absorbents selection

  16. Tourists’ attitudes towards ban on smoking in air-conditioned hotel lobbies in Thailand

    Science.gov (United States)

    Viriyachaiyo, V; Lim, A

    2009-01-01

    Background: Thailand is internationally renowned for its stringent tobacco control measures. In Thailand, a regulation banning smoking in air-conditioned hotel lobbies was issued in late 2006, causing substantial apprehension within the hospitality industry. A survey of tourists’ attitudes toward the ban was conducted. Methods: A cross-sectional survey of 5550 travellers staying in various hotels in Bangkok, Surat Thani, Phuket, Krabi and Songkhla provinces, October 2005 to December 2006. Travellers aged 15 years or older with a check-in duration of at least one day and willing to complete the questionnaire were requested by hotel staff to fill in the 5-minute questionnaire at check-in or later at their convenience. Results: Secondhand cigarette smoke was recognised as harmful to health by 89.7% of respondents. 47.8% of travellers were aware of the Thai regulation banning smoking in air-conditioned restaurants. 80.9% of the respondents agreed with the ban, particularly female non-smokers. 38.6% of survey respondents indicated that they would be more likely to visit Thailand again because of the regulation, 53.4% that the regulation would not affect their decision and 7.9% that they would be less likely to visit Thailand again. Conclusion: Banning smoking in air-conditioned hotel lobbies in Thailand is widely supported by tourists. Enforcement of the regulation is more likely to attract tourists than dissuade them from holidaying in Thailand. PMID:19364754

  17. Ice thermal storage air conditioning system for electric load leveling; Denryoku heijunka to hyochikunetsu system

    Energy Technology Data Exchange (ETDEWEB)

    Shigenaga, Y. [Daikin Industries Ltd., Osaka (Japan)

    1998-08-15

    Thermal storage air conditioning system is the one to use energy stored into thermal storing materials by using night electric power and to operate effective air conditioning. Therefore, as load can be treated by the stored energy, volume of the apparatus can be reduced. And, by reduction of the consumed power at day time, it can contribute to leveling of electric power demand. In general, there are two types in the thermal storage method: one is a method to store as thermal energy, and the other is that to store as chemical energy. For conditions required for the storing materials, important elements on their actual uses are not only physical properties such as large thermal storage per unit and easy thermal in- and out-puts, but also safety, long-term reliability, and easy receiving and economics containing future. The ice thermal storage air conditioning system is classified at the viewpoint of type of ice, kind of thermal storing medium, melting method on using cooling and heating, kinds of thermal medium on cooling and heating. 3 refs., 5 figs., 2 tabs.

  18. Complex dynamics and chaos control of duopoly Bertrand model in Chinese air-conditioning market

    International Nuclear Information System (INIS)

    Yi, Qi Guo; Zeng, Xiang Jin

    2015-01-01

    Highlights: •A dynamic duopoly Bertrand model with bounded rationality and quadratic cost function. •In Chinese air-conditioning market the boundary equilibrium point is locally stable. •The Lyapunov dimension of the chaos attractor is 1.9585. •The adjustment speeds may cause a market structure to behave chaotically. •The chaotic behavior can be controlled by decreasing the degree of substitutability. -- Abstract: A dynamic duopoly Bertrand model with quadratic cost function which is closer to reality and different from previous researches is discussed. The model is applied into air-conditioning market where the boundary equilibrium point is locally stable. Numerical simulations illustrate that the stability of Nash equilibrium strongly depends on the speed of adjustment of bounded rational player. The adjustment speeds and the degree of substitutability may undermine the stability of the equilibrium and cause a market structure to behave chaotically. The Lyapunov dimension of the chaos attractor is 1.9585 under some conditions. The stabilization of the chaotic behavior can be obtained by reducing the degree of substitutability. The results have an important theoretical and practical significance to Chinese air-conditioning market

  19. Tourists' attitudes towards ban on smoking in air-conditioned hotel lobbies in Thailand.

    Science.gov (United States)

    Viriyachaiyo, V; Lim, A

    2009-06-01

    Thailand is internationally renowned for its stringent tobacco control measures. In Thailand, a regulation banning smoking in air-conditioned hotel lobbies was issued in late 2006, causing substantial apprehension within the hospitality industry. A survey of tourists' attitudes toward the ban was conducted. A cross-sectional survey of 5550 travellers staying in various hotels in Bangkok, Surat Thani, Phuket, Krabi and Songkhla provinces, October 2005 to December 2006. Travellers aged 15 years or older with a check-in duration of at least one day and willing to complete the questionnaire were requested by hotel staff to fill in the 5-minute questionnaire at check-in or later at their convenience. Secondhand cigarette smoke was recognised as harmful to health by 89.7% of respondents. 47.8% of travellers were aware of the Thai regulation banning smoking in air-conditioned restaurants. 80.9% of the respondents agreed with the ban, particularly female non-smokers. 38.6% of survey respondents indicated that they would be more likely to visit Thailand again because of the regulation, 53.4% that the regulation would not affect their decision and 7.9% that they would be less likely to visit Thailand again. Banning smoking in air-conditioned hotel lobbies in Thailand is widely supported by tourists. Enforcement of the regulation is more likely to attract tourists than dissuade them from holidaying in Thailand.

  20. Characteristics of radon and its progeny concentrations in air-conditioned office buildings in Tokyo

    International Nuclear Information System (INIS)

    Tokonami, S.; Furukawa, M.; Shicchi, Y.; Sanada, T.; Yamada, Y.

    2003-01-01

    A series of measurements were carried out to understand the characteristics of radon and its progeny in air-conditioned office buildings. Long-term measurements of radon were made with etched track detectors. Continuous measurements of radon and its progeny concentrations were also conducted in some buildings to study their temporal variations. The results show that radon and its progeny concentrations routinely varied along with working activities. They are generally low while people are working, due to air conditioning, whereas they rise steadily after the air conditioning stops. When considering action levels not only in homes but also workplaces, attention should be paid to annual doses from the viewpoint of radiation protection. The annual dose is generally estimated with a long-term measurement of radon concentration using a passive device such as an etched track detector. Since its reading corresponds to a long-term average concentration regardless of working hours, the annual dose will be overestimated. When comparing a real dose after considering the working hours, they differ by a factor of more than 2. (author)

  1. The natural gas air-conditioning; La climatisation au gaz naturel. Un avenir prometteur, une technique confirmee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The natural gas air-conditioning market is in growth (it will cover 10% of the market in 2002).To illustrate the possibilities of this energy source, this paper presents three examples of the natural gas air-conditioning in France. The technical aspects, the cost and the advantages of such systems are discussed. (A.L.B.)

  2. Development of KSC program for investigating and generating field failure rates. Reliability handbook for ground support equipment

    Science.gov (United States)

    Bloomquist, C. E.; Kallmeyer, R. H.

    1972-01-01

    Field failure rates and confidence factors are presented for 88 identifiable components of the ground support equipment at the John F. Kennedy Space Center. For most of these, supplementary information regarding failure mode and cause is tabulated. Complete reliability assessments are included for three systems, eight subsystems, and nine generic piece-part classifications. Procedures for updating or augmenting the reliability results are also included.

  3. Achieving better energy-efficient air conditioning – A review of technologies and strategies

    International Nuclear Information System (INIS)

    Chua, K.J.; Chou, S.K.; Yang, W.M.; Yan, J.

    2013-01-01

    Air conditioning is essential for maintaining thermal comfort in indoor environments, particularly for hot and humid climates. Today, air conditioning, comprising cooling and dehumidification, has become a necessity in commercial and residential buildings and industrial processes. It accounts for a major share of the energy consumption of a building or facility. In tropical climates, the energy consumed by heating, ventilation and air-conditioning (HVAC) can exceed 50% of the total energy consumption of a building. This significant figure is primarily due to the heavy duty placed on cooling technologies to remove both sensible and latent heat loads. Therefore, there is tremendous potential to improve the overall efficiency of the air-conditioning systems in buildings. Based on today’s practical technology for cooling, the major components of a chiller plant are (1) compressors, (2) cooling towers, (3) pumps (chilled and cooling water) and (4) fans in air handling units. They all consume mainly electricity to operate. When specifying the kW/R ton of a plant, there are two levels of monitoring cooling efficiency: (1) at the efficiency of the chiller machines or the compressors which consume a major amount of electricity; and (2) at the overall efficiency of cooling plants which include the cooling towers, pumps for moving coolant (chilled and cooling water) to all air-handling units. Pragmatically, a holistic approach is necessary towards achieving a low energy input per cooling achieved such as 0.6 kW/R ton cooling or lower by considering all aspects of the cooling plant. In this paper, we present a review of recent innovative cooling technology and strategies that could potentially lower the kW/R ton of cooling systems – from the existing mean of 0.9 kW/R ton towards 0.6 kW/R ton or lower. The paper, broadly divided into three key sections (see Fig. 2), begins with a review of the recent novel devices that enhances the energy efficiency of cooling systems at

  4. IEA SHC Task 38 'Solar air-conditioning and refrigeration'. Danish participation 2007-2010; IEA SHC Task 38 'Solar air-conditioning and refrigeration'. Dansk deltagelse 2007-2010

    Energy Technology Data Exchange (ETDEWEB)

    Ellehauge, K. (Ellehauge og Kildemoes, Aarhus (Denmark)); Muenster, E. (PlanEnergi, Skoerping (Denmark)); Reinholdt, L. (Teknologisk Institut, Aarhus (Denmark)); Minds, S. (AC-Sun Aps, Horsens (Denmark))

    2011-03-15

    Skive City Hall. The Technological Institute has participated closely in preparing the report for subtask A 'Small Systems'. Furthermore The Technological Institute had the role as coordinator of activities around the optimization of 'heat rejection'. In this context it is especially the derived electricity for pumps and fans in the heat emitter (cooling tower, dry cooler, etc.) that are looked at. Traditionally heat driven refrigeration machines are controlled by regulating the driving heat flow (lower regeneration temperature). This has however, for most types of sys-tems, negative impact on the system efficiency and thus the power consumption of auxiliary equipment. This has led to the development of an alternative regulation strategy tested at Skive City Hall plant. In 2009 it was planned to attach adiabatic pre-cooling of the air cooling coils at Skive City Hall, however the solution proved to be quite expensive. Further optimization of the solution was therefore not implemented. The study of adiabatic pre-cooling was instead made in a laboratory setting at the Technological Institute. This was combined with the test of a new air cooling system, based on indirect evaporation of water. The test was conducted on a cooler purchased from the Netherlands and a MST project was demonstrating this technology to heat driven air conditioning in a supermarket. AC Sun has designed and produced an optimized prototype 2 and begun data collection. Prototype (2) is flexibly designed for testing different bearing solutions. The prototype is installed in a buffer tank connected to the heating elements as external heat source acting as a collector. Prototype 2 will be used as the final internal testing station before the final design and manufacture of test facilities for 'field' test in 5 test stations Denmark, Germany, Italy, Spain and Malaysia, respectively. Most of the testing stations are expected operating in spring 2011. Ellehauge and Kildemoes

  5. Air conditioning technology. Vol. 1. Calculation, design, meteorological data. Standards, guidelines. As of October 31, 1986. Raumlufttechnik. Bd. 1. Berechnung, Konstruktion, meteorologische Daten. Normen, Richtlinien. Stand der abgedruckten Normen: 31. Oktober 1986

    Energy Technology Data Exchange (ETDEWEB)

    1986-01-01

    Since 1970 the energy consumption of air-conditioning systems has almost been reduced by half. This has been achieved by means of improved technologies and on the basis of a change in technological awareness. Revised DIN Standards have contributed to this as well. The application of the standards compiled in the DIN pocket book No. 217 'Raumlufttechnik 1' (Air-conditioning Technology 1) will secure the associated systems to actually generate the desired air-conditioning effects. With its major DIN Standards for the calculation and design of air-conditioning systems, this DIN pocket book turns out to be a valuable guide and tool for planners, manufacturers and operators. In addition, its annex supplies substantiated information on the control of HVAC systems (VDI/VDE 3525 BI) and contains the guideline for the acceptance testing of HVAC systems (VDI/2079), the draft for the building inspection guideline on fire protection requirements on ventilation systems, and annotations for air-conditioning installations in public buildings.

  6. Performance characteristics of a prompt gamma-ray activation analysis (PGAA) system equipped with a new compact D-D neutron generator

    Energy Technology Data Exchange (ETDEWEB)

    Park, Yong Joon; Song, Byung Chul; Im, Hee-Jung [Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute, Dukjin-dong 150-1, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Kim, Jong-Yun [Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute, Dukjin-dong 150-1, Yuseong-gu, Daejeon 305-353 (Korea, Republic of)], E-mail: kjy@kaeri.re.kr

    2009-07-21

    A new prompt gamma-ray activation analysis (PGAA) system equipped with a compact deuterium-deuterium (D-D) neutron generator has been developed for fast detection of explosives and chemical warfare agents. The PGAA system was built based on a fully high-voltage-shielded, axial D-D neutron generator with a radio frequency (RF)-driven ion source. The ionic current of the compact neutron generator was determined as a function of the acceleration voltage at various RF powers. Monoenergetic neutrons (2.45 MeV) with a neutron yield of >1x10{sup 7} n/s were obtained at a deuterium pressure of 8.0 mTorr, an acceleration voltage of 80 kV, and an RF power of 1.1 kW. The performance of the PGAA system was examined by studying the dependence of a prompt gamma-ray count rate on crucial operating parameters.

  7. Commentary: Air-conditioning as a risk for increased use of healthservices

    Energy Technology Data Exchange (ETDEWEB)

    Mendell, Mark J.

    2004-06-01

    In this issue of the journal, Preziosi et al. [2004] report the first study to assess differences in the utilization of health care related to the presence of air-conditioning in office workplaces. Although the study was simple and cross-sectional, the data variables from questionnaires, and the findings subject to a variety of questions, the findings are striking enough to deserve clarification. The study used a large random national sample of French women assembled for another purpose (to study antioxidant nutrients and prevention of cancer and cardiovascular disease). Participants reported health services and health events in monthly questionnaires over 1 year, and in one questionnaire in the middle of that period also reported whether air-conditioning was in use at their workplace. Fifteen percent of participants reported air-conditioning at work. Analyses adjusting for age and smoking status of participants found increases in most outcomes assessed: use of specific kinds of physicians, sickness absence, and hospital stays. While the increases in odds ratios (OR) and 95% confidence intervals (CI) were statistically significant for only otorhinolaryngology [OR (95% CI) = 2.33 (1.35-4.04)] and sickness absence [1.70 (1.13-2.58)], other increases were notable--dermatology [1.6 (0.98-2.65)]; hospital stay [1.51 (0.92-2.45)], and pneumonology [2.10 (0.65-6.82)]. The least elevated outcomes were for general practice medicine [0.99 (0.65-1.48)] and global medical visits [1.18 (0.67-2.07)]. [Preziosi et al., 2004 ,(Table 2)] Odds ratios for relatively common health outcomes often lie farther from the null than the risk ratios most useful for quantifying the increase in risk. Risk ratios, or prevalence ratios (PRs, the equivalent measure of effect for cross-sectional data), have seldom been used because of the convenience and availability of logistic regression models that estimate odds ratios. With baseline prevalences ranging up to 85.7% in the data from Preziosi et

  8. Mobil laboratory for the evaluation on site of the power electric equipment, second generation; Laboratorio movil para la evaluacion en sitio del equipo electrico de potencia, segunda generacion

    Energy Technology Data Exchange (ETDEWEB)

    Carrillo C, Jaime; Escorsa M, Oscar; Estrada G, Javier A; Iturbe F, Marlene; Robles P, Edgar [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2005-07-01

    To the interior of the Generation of Electrical Equipment (GEE) of the Instituto de Investigaciones Electricas, one of the main activities is the diagnosis of the electrical equipment in service. It is well known that the power equipment represents a strong investment that requires the guarantee that it has been manufactured, installed and operated satisfactorily. The life expectancy of these devices is of thirty years, however, many of them already have surpassed that expectation. The rehabilitation or substitution of the equipment implies new investments that are needed for an evaluation of the real condition of the equipment to carry out such rehabilitation. One of the tools necessary to carry out the diagnosis, is a movable laboratory that facilitates all the necessary tools to perform a meticulous analysis that would allow, the client, to make high cost decisions. The application of the movable laboratory is advisable from the inauguration of the equipment. The electrical mechanisms are factory tested in accordance with standardized protocols; it guarantees the fulfillment of the necessary requirements for a correct operation. Nevertheless, when taking them to the assembly site, these are subjected to a series of processes and mechanical stresses that could alter the equipment conditions and its integrity. [Spanish] Al interior de la Generacion de Equipos Electricos (GEE) del Instituto de Investigaciones Electricas, una de las principales actividades es el diagnostico del equipo electrico en servicio. Es bien sabido que los equipos de potencia representan una fuerte inversion que requiere la garantia de que se ha fabricado, instalado y operado satisfactoriamente. La esperanza de vida de estos dispositivos es de treinta anos, no obstante, muchos de ellos ya han superado esa expectativa. La rehabilitacion o sustitucion de equipos, implica nuevas inversiones que precisan un conocimiento del estado real del equipo para llevarla a cabo. Una de las herramientas

  9. Load Distribution of Semi-Central Evaporative Cooling Air-Conditioning System Based on the TRNSYS Platform

    Directory of Open Access Journals (Sweden)

    Ji Li

    2018-05-01

    Full Text Available Evaporative cooling is a green, energy-efficient cooling technology adopted in hot and dry regions, which has wider application in the field of air-conditioning systems. Outdoor meteorological parameters have a great influence on the operation mode and control strategy of evaporative cooling air-conditioning systems, and the system load distribution and system configuration will be affected. This paper aims at investigating the load distribution of semi-central evaporative cooling air-conditioning systems under the condition of hourly outdoor meteorological parameters. Firstly, this paper introduced the design partition, operation mode, controlling strategy and load distribution method on semi-central evaporative cooling air-conditioning system. Then, taking an office building in Lanzhou (China as an example, the evaporative cooling air-conditioning system was divided into five regions and the load distribution was simulated by TRNSYS (The Transient Energy System Simulation Tool under the condition of hourly outdoor meteorological parameters. Finally, the results have shown that the evaporative cooling air-conditioning system can provide 25.46% of the building loads, which was of great significance to reduce the energy consumption of air-conditioning system.

  10. Experimental analysis of fuzzy controlled energy efficient demand controlled ventilation economizer cycle variable air volume air conditioning system

    Directory of Open Access Journals (Sweden)

    Rajagopalan Parameshwaran

    2008-01-01

    Full Text Available In the quest for energy conservative building design, there is now a great opportunity for a flexible and sophisticated air conditioning system capable of addressing better thermal comfort, indoor air quality, and energy efficiency, that are strongly desired. The variable refrigerant volume air conditioning system provides considerable energy savings, cost effectiveness and reduced space requirements. Applications of intelligent control like fuzzy logic controller, especially adapted to variable air volume air conditioning systems, have drawn more interest in recent years than classical control systems. An experimental analysis was performed to investigate the inherent operational characteristics of the combined variable refrigerant volume and variable air volume air conditioning systems under fixed ventilation, demand controlled ventilation, and combined demand controlled ventilation and economizer cycle techniques for two seasonal conditions. The test results of the variable refrigerant volume and variable air volume air conditioning system for each techniques are presented. The test results infer that the system controlled by fuzzy logic methodology and operated under the CO2 based mechanical ventilation scheme, effectively yields 37% and 56% per day of average energy-saving in summer and winter conditions, respectively. Based on the experimental results, the fuzzy based combined system can be considered to be an alternative energy efficient air conditioning scheme, having significant energy-saving potential compared to the conventional constant air volume air conditioning system.

  11. Design and Simulation of an Air Conditioning Project in a Hospital Based on Computational Fluid Dynamics

    Directory of Open Access Journals (Sweden)

    Ding X. R.

    2017-06-01

    Full Text Available This study aims to design a novel air cleaning facility which conforms to the current situation in China, and moreover can satisfy our demand on air purification under the condition of poor air quality, as well as discuss the development means of a prototype product. Air conditions in the operating room of a hospital were measured as the research subject of this study. First, a suitable turbulence model and boundary conditions were selected and computational fluid dynamics (CFD software was used to simulate indoor air distribution. The analysis and comparison of the simulation results suggested that increasing the area of air supply outlets and the number of return air inlets would not only increase the area of unidirectional flow region in main flow region, but also avoid an indoor vortex and turbulivity of the operating area. Based on the summary of heat and humidity management methods, the system operation mode and relevant parameter technologies as well as the characteristics of the thermal-humidity load of the operating room were analyzed and compiled. According to the load value and parameters of indoor design obtained after our calculations, the airflow distribution of purifying the air-conditioning system in a clean operating room was designed and checked. The research results suggested that the application of a secondary return air system in the summer could reduce energy consumption and be consistent with the concept of primaiy humidity control. This study analyzed the feasibility and energy conservation properties of cleaning air-conditioning technology in operating rooms, proposed some solutions to the problem, and performed a feasible simulation, which provides a reference for practical engineering.

  12. Modeling and Simulation of Thermal Performance of Solar-Assisted Air Conditioning System under Iraq Climate

    Directory of Open Access Journals (Sweden)

    Najim Abid Jassim

    2016-08-01

    Full Text Available In Iraq most of the small buildings deployed a conventional air conditioning technology which typically uses electrically driven compressor systems which exhibits several clear disadvantages such as high energy consumption, high electricity at peak loads. In this work a thermal performance of air conditioning system combined with a solar collector is investigated theoretically. The hybrid air conditioner consists of a semi hermetic compressor, water cooled shell and tube condenser, thermal expansion valve and coil with tank evaporator. The theoretical analysis included a simulation for the solar assisted air-conditioning system using EES software to analyze the effect of different parameters on the power consumption of compressor and the performance of system. The results show that refrigeration capacity is increased from 2.7 kW to 4.4kW, as the evaporating temperature increased from 3 to 18 ºC. Also the power consumption is increased from 0.89 kW to 1.08 kW. So the COP of the system is increased from 3.068 to 4.117. The power consumption is increased from 0.897 kW to 1.031 kW as the condensing temperature increased from 35 ºC to 45 ºC. While the COP is decreased from 3.89 to 3.1. The power consumption is decreased from 1.05 kW to 0.7kW as the solar radiation intensity increased from 300 W/m2 to 1000 W/m2, while the COP is increased from 3.15 to 4.8. A comparison between the simulation and available experimental data showed acceptable agreement.

  13. Air quality and passenger comfort in an air-conditioned bus micro-environment.

    Science.gov (United States)

    Zhu, Xiaoxuan; Lei, Li; Wang, Xingshen; Zhang, Yinghui

    2018-04-12

    In this study, passenger comfort and the air pollution status of the micro-environmental conditions in an air-conditioned bus were investigated through questionnaires, field measurements, and a numerical simulation. As a subjective analysis, passengers' perceptions of indoor environmental quality and comfort levels were determined from questionnaires. As an objective analysis, a numerical simulation was conducted using a discrete phase model to determine the diffusion and distribution of pollutants, including particulate matter with a diameter air quality and dissatisfactory thermal comfort conditions in Jinan's air-conditioned bus system. To solve these problems, three scenarios (schemes A, B, C) were designed to alter the ventilation parameters. According to the results of an improved simulation of these scenarios, reducing or adding air outputs would shorten the time taken to reach steady-state conditions and weaken the airflow or lower the temperature in the cabin. The airflow pathway was closely related to the layout of the air conditioning. Scheme B lowered the temperature by 0.4 K and reduced the airflow by 0.01 m/s, while scheme C reduced the volume concentration of PM 10 to 150 μg/m 3 . Changing the air supply angle could further improve the airflow and reduce the concentration of PM 10 . With regard to the perception of airflow and thermal comfort, the scheme with an airflow provided by a 60° nozzle was considered better, and the concentration of PM 10 was reduced to 130 μg/m 3 .

  14. Duct corrosion in the ventilating air conditioning system for Main Control Room

    International Nuclear Information System (INIS)

    Yamada, Kohei; Kobayashi, Takashi; Minami, Akiko; Fukuba, Kazushi

    2014-01-01

    Higashidori Nuclear Power Station, start-of-operation in December 2005, is a relatively new plant. We decided to get original data of air duct condition to determine maintenance policy of air duct, because planned maintenance of air duct has never been done and the corrosion of air duct has occurred in other plant. In January 2014, we found a corrosion-hole at the downstream of the inlet damper in the ventilating air conditioning system for Main Control Room (MCR). We supposed that the cause of rapid corrosion is related to the characteristic environment of this site. (author)

  15. Air-conditioning in the 21st century: impact on human productivity and energy consumption

    DEFF Research Database (Denmark)

    Fanger, Povl Ole

    2000-01-01

    Although air-conditioning has played a positive role for economic development in warm climates, its image is globally mixed. Field studies demonstrate that there are substantial numbers of dissatisfied people in many buildings, among them those suffering from Sick Building Syndrome (SBS) symptoms...... environment on human productivity, health and comfort. The principles of excellence can be provided with moderate energy consumption. But the success of excellent indoor environments will increase the demand for improvement globally and the required energy supply will provide a challenge for the world...

  16. Efficient stratified ventilation - air conditioning of skating rinks; Effiziente Schichtlueftung - Klimatisierung von Eissporthallen

    Energy Technology Data Exchange (ETDEWEB)

    Fiedler, E. [Fa. Caverion, Aachen (Germany)

    2007-07-01

    Air conditioning of ice rinks is not just a matter of user comfort. Excessive humidity will cause frosting and poor ice quality while mist formation may interfere with hockey games. Constant condensation in the roof area causes severe damage of the building and is assumed to be a maine cause of the breakdown of the Bad Reichenhall skating hall in January 2006. In the Wolfsburg ice arena, an innovative ventilation concept was implemented which meets complex user demands and is characterized by its high energy efficiency. (orig.)

  17. Performance study of desiccant coated heat exchanger air conditioning system in winter

    International Nuclear Information System (INIS)

    Ge, T.S.; Dai, Y.J.; Wang, R.Z.

    2016-01-01

    Highlights: • Performance of desiccant coated heat exchanger AC system is predicted. • Effects of main operation parameters and climatic conditions are discussed. • Regeneration temperature of 30 °C is recommended under simulation condition. • Higher ambient humidity ratio results in increased humidity ratio of supply air. • Temperature of ambient air has neglectable effect on supply air. - Abstract: Conventional air source heat pump system faces several challenges when adopted in winter season. Solid desiccant air conditioning system can provide humidification and heating power simultaneously and can be driven by low grade thermal energy; it provides a good alternative for air source heat pump systems. However, conventional solid desiccant air conditioning system adopts desiccant wheel with high cost as core component, which hinders the development of such system. Recently, desiccant coated heat exchanger (DCHE) with low initial cost and high efficiency was developed and this paper aims to investigate performance of DCHE air conditioning system adopted in Shanghai winter season. Performance of the system is predicted by a developed mathematical model where supply air states, mass of humidification and coefficient of performance (COP) are adopted as performance indices to evaluate the feasibility and energy utilization ratio of the system. Effects of regeneration water temperature on system performance are analyzed. It is found that under the simulation condition, relatively low regeneration temperature (such as 20 °C) cannot meet the designed standard and relatively high regeneration temperature (such as 40 °C) provides too much extra heating power, thus moderate regeneration temperature around 30 °C is recommended. Meanwhile, switch time is a crucial operation parameter for the system to obtain satisfied supply air, switch time from 40 s to 80 s and from 70 s to 240 s are recommended for transient and average supply air states, respectively. Both

  18. Towards energy efficient operation of Heating, Ventilation and Air Conditioning systems via advanced supervisory control design

    Science.gov (United States)

    Oswiecinska, A.; Hibbs, J.; Zajic, I.; Burnham, K. J.

    2015-11-01

    This paper presents conceptual control solution for reliable and energy efficient operation of heating, ventilation and air conditioning (HVAC) systems used in large volume building applications, e.g. warehouse facilities or exhibition centres. Advanced two-level scalable control solution, designed to extend capabilities of the existing low-level control strategies via remote internet connection, is presented. The high-level, supervisory controller is based on Model Predictive Control (MPC) architecture, which is the state-of-the-art for indoor climate control systems. The innovative approach benefits from using passive heating and cooling control strategies for reducing the HVAC system operational costs, while ensuring that required environmental conditions are met.

  19. Single room control for user-optimised room air conditions; Einzelraumregelung fuer nutzungsoptimiertes Raumklima

    Energy Technology Data Exchange (ETDEWEB)

    Lezius, A. [Staefa Control System GmbH, Leinfelden-Echterdingen (Germany)

    1995-12-31

    In chapter 14 of the anthology about building control the single room control for achieving user-optimised room air conditions is described. The following aspects are discussed: What is comfort? What is economic efficiency? Systems for secondary air treatment, adapted functions of the measurement and control technique, management functions, orientation of the demand at the use, investment and amortisation. (BWI) [Deutsch] Kapitel 14 des Sammelbandes ueber Building control ist dem Thema der Einzelraumregelung zur Erzielung eines nutzungsoptimierten Raumklimas gewidmet. In diesem Zusammenhang werden folgende Themenbereiche angesprochen: Was ist Komfort? Was ist Wirtschaftlichkeit? Systeme fuer sekundaere Luftbehandlung; Angepasste Funktionen der MSR-Technik; Managementfunktionen; Bedarfsorientierung an der Nutzung; Investition und Amortisation. (BWI)

  20. Refrigeration generation using expander-generator units

    Science.gov (United States)

    Klimenko, A. V.; Agababov, V. S.; Koryagin, A. V.; Baidakova, Yu. O.

    2016-05-01

    The problems of using the expander-generator unit (EGU) to generate refrigeration, along with electricity were considered. It is shown that, on the level of the temperatures of refrigeration flows using the EGU, one can provide the refrigeration supply of the different consumers: ventilation and air conditioning plants and industrial refrigerators and freezers. The analysis of influence of process parameters on the cooling power of the EGU, which depends on the parameters of the gas expansion process in the expander and temperatures of cooled environment, was carried out. The schematic diagram of refrigeration generation plant based on EGU is presented. The features and advantages of EGU to generate refrigeration compared with thermotransformer of steam compressive and absorption types were shown, namely: there is no need to use the energy generated by burning fuel to operate the EGU; beneficial use of the heat delivered to gas from the flow being cooled in equipment operating on gas; energy production along with refrigeration generation, which makes it possible to create, using EGU, the trigeneration plants without using the energy power equipment. It is shown that the level of the temperatures of refrigeration flows, which can be obtained by using the EGU on existing technological decompression stations of the transported gas, allows providing the refrigeration supply of various consumers. The information that the refrigeration capacity of an expander-generator unit not only depends on the parameters of the process of expansion of gas flowing in the expander (flow rate, temperatures and pressures at the inlet and outlet) but it is also determined by the temperature needed for a consumer and the initial temperature of the flow of the refrigeration-carrier being cooled. The conclusion was made that the expander-generator units can be used to create trigeneration plants both at major power plants and at small energy.

  1. HVAC-DYNAMICS - a tool for quality assurance in relation to delivery of air-conditioning systems. [Heating, ventilating and air conditioning]. HVAC-DYNAMICS - et redskap for kvalitetsikring av sluttleveransen i klima-anlegg

    Energy Technology Data Exchange (ETDEWEB)

    Novakovic, V [SINTEF Varmeteknikk, Seksjon VVS (NO)

    1990-07-01

    HVAC-DYNAMICS is a computerized tool for quality assurance of the functioning of an air-conditioning system at the time of delivery. The system's efficiency in the case of fluctuating and critical operation is evaluated. The HVAC-DYNAMICS gives an optimal choice for air-conditioning systems regarding indoor climate, efficiency demands and energy consumption. The program can also be use for calibration of regulators, fault-finding, and training purposes. (CLS).

  2. Open-Source Assisted Laboratory Automation through Graphical User Interfaces and 3D Printers: Application to Equipment Hyphenation for Higher-Order Data Generation.

    Science.gov (United States)

    Siano, Gabriel G; Montemurro, Milagros; Alcaráz, Mirta R; Goicoechea, Héctor C

    2017-10-17

    Higher-order data generation implies some automation challenges, which are mainly related to the hidden programming languages and electronic details of the equipment. When techniques and/or equipment hyphenation are the key to obtaining higher-order data, the required simultaneous control of them demands funds for new hardware, software, and licenses, in addition to very skilled operators. In this work, we present Design of Inputs-Outputs with Sikuli (DIOS), a free and open-source code program that provides a general framework for the design of automated experimental procedures without prior knowledge of programming or electronics. Basically, instruments and devices are considered as nodes in a network, and every node is associated both with physical and virtual inputs and outputs. Virtual components, such as graphical user interfaces (GUIs) of equipment, are handled by means of image recognition tools provided by Sikuli scripting language, while handling of their physical counterparts is achieved using an adapted open-source three-dimensional (3D) printer. Two previously reported experiments of our research group, related to fluorescence matrices derived from kinetics and high-performance liquid chromatography, were adapted to be carried out in a more automated fashion. Satisfactory results, in terms of analytical performance, were obtained. Similarly, advantages derived from open-source tools assistance could be appreciated, mainly in terms of lesser intervention of operators and cost savings.

  3. Measurement of the irradiation of generating lamps of radiation ultraviolet type A used in tan equipment Sportarredo model Ringo 1200

    International Nuclear Information System (INIS)

    Gama T, G.

    2010-09-01

    In the last years has been developed in the cosmetology market the application of ultraviolet radiation (UV) in known equipment s as cameras or tan beds to obtain a change in the pigmentation of the skin. In Mexico, this fashion has entered without the appropriate recommendations of prevention against the risks of the adverse effects from the disproportionate exhibition to such non ionizing energy form; which is electromagnetic radiation in the interval of 400 nm to 100 nm of wave longitude, classified in near UV-A of 400 nm to 315 nm, and distant: UV-B of 315 nm to 280 nm and UV-C of 280 nm to 100 nm. Therefore, they have not been included in the national normative the necessary regulations regarding the operation parameters of the tan cameras for the E irradiation levels. The level E is defined as the incident radiation power in a receiver surface to a specific localization and relative orientation to the radiant surface expressed in units of the International System, W/m 2 or MW/cm 2 . The objective of this work is to show the measurement results for the E of a camera that contains two emitters arrangements, a first to whole body that consist of 8 lamp pairs model B17L of 160 Watts, which will have a nominal E of 358 W/m 2 (35.8 MW/cm 2 ) for UV type A and 3.3 W/m 2 (0.33 MW/cm 2 ) for UV type B; one second to face of 8 lamps model KALFASUN 630, with an E of 568 W/m 2 (56.8 MW/cm 2 ) for UV type A and 2.97 W/m 2 (0.297 MW/cm 2 ) for UV type B. The E measurements are carried out for UV-A with the body and face lamp, respectively; with two instruments: photometer mark Sportarredo, model BF01, series E009, and radiometer mark Ets without specified model. Additional the treatment time is verified with the chronometer of the digital screen of the equipment comparing it with a digital meter with resolution of 0.001 s. Conclusion: the lamps do not fulfill the E nominal values reported by the manufacturer, being minors 3.2 to 1.75 times their nominal value for the body

  4. Fuzzy logic control of air-conditioning system in residential buildings

    Directory of Open Access Journals (Sweden)

    Abdel-Hamid Attia

    2015-09-01

    Full Text Available There has been a rising concern in reducing the energy consumption in building. Heating ventilation and air condition system is the biggest consumer of energy in building. In this study, fuzzy logic control of the air conditioning system of building for efficient energy operation and comfortable environment is investigated. A theoretical model of the fan coil unit (FCU and the heat transfer between air and coolant fluid is derived. The controlled variables are the room temperature and relative humidity and control consequents are the percentage of chilled and hot water flow rates at summer and the percentage of hot water and steam injected flow rates at winter. A computer simulation has been conducted and fuzzy control results are compared with that of conventional Proportional-Integral-Derivative control. It was found that the proposed control strategy satisfies the space load and at the same time to achieve the comfort zone, as defined by the ASHRAE code. Meanwhile PID control fails to adjust the room temperature at part-load operations. It has been demonstrated that fuzzy controller operation is more efficient and consumes less energy than PID control.

  5. A robust model predictive control strategy for improving the control performance of air-conditioning systems

    International Nuclear Information System (INIS)

    Huang Gongsheng; Wang Shengwei; Xu Xinhua

    2009-01-01

    This paper presents a robust model predictive control strategy for improving the supply air temperature control of air-handling units by dealing with the associated uncertainties and constraints directly. This strategy uses a first-order plus time-delay model with uncertain time-delay and system gain to describe air-conditioning process of an air-handling unit usually operating at various weather conditions. The uncertainties of the time-delay and system gain, which imply the nonlinearities and the variable dynamic characteristics, are formulated using an uncertainty polytope. Based on this uncertainty formulation, an offline LMI-based robust model predictive control algorithm is employed to design a robust controller for air-handling units which can guarantee a good robustness subject to uncertainties and constraints. The proposed robust strategy is evaluated in a dynamic simulation environment of a variable air volume air-conditioning system in various operation conditions by comparing with a conventional PI control strategy. The robustness analysis of both strategies under different weather conditions is also presented.

  6. Research on mass transfer and actual performance of the membrane regeneration air-conditioning system

    International Nuclear Information System (INIS)

    Li, Xiu-Wei; Zhang, Xiao-Song; Chen, Qing

    2015-01-01

    Highlights: • Experimental research has been made on the membrane air-conditioning system. • We develop mass transfer models for the membrane regeneration process. • The paper exposes the actual performance of the system. • Increase of membrane pairs improves the performance. - Abstract: Absorption air-conditioning system has great advantages in energy conservation and environmental protection. To improve the performance of the traditional system, the membrane regeneration absorption system was proposed. Its COP could approach 6 by regenerating absorbent solution with the ion exchange membranes. However, the theoretical conclusion has not been supported by the experiment. This paper presents the experimental research of the membrane regeneration process. It has investigated the mass transfer process, energy efficiency and actual performance under different working conditions. Based on that, a mass transfer model has been developed and the influences of some key parameters have been exposed. It found the regeneration performance is mainly influenced by the current intensity. The calculation results with the model agree well the experimental data. The actual efficiency was lower than 50%, caused by energy loss in heat and electrochemical reactions. The actual COP is between 1 and 3, lower current intensity and more membrane pairs could improve it.

  7. Ventilation and air conditioning system in waste treatment and storage facilities

    International Nuclear Information System (INIS)

    Kinoshita, Hirotsugu; Sugawara, Kazushige.

    1987-01-01

    So far, the measures concerning the facilities for treating and storing radioactive wastes in nuclear fuel cycle in Japan were in the state which cannot be said to be sufficient. In order to cope with this situation, electric power companies constructed and operated radioactive waste concentration and volume reduction facilities, solid waste storing facilities for drums, high level solid waste storing facilities, spent fuel cask preserving facilities and so on successively in the premises of nuclear power stations, and for the wastes expected in future, the research and the construction plan of the facilities for treating and storing low, medium and high level wastes have been advanced. The ventilation and air conditioning system for these facilities is the important auxiliary system which has the mission of maintaining safe and pleasant environment in the facilities and lowering as far as possible the release of radioactive substances to outside. The outline of waste treatment and storage facilities is explained. The design condition, ventilation and air conditioning method, the features of respective waste treatment and storage facilities, and the problems for the future are described. Hereafter, mechanical ventilation system continues to be the main system, and filters become waste, while the exchange of filters is accompanied by the radiation exposure of workers. (Kako, I.)

  8. Cleaning and air conditioning device for atmosphere in thermonuclear reactor chamber

    International Nuclear Information System (INIS)

    Ishida, Seiji.

    1993-01-01

    The device of the present invention removes tritium efficiently and attains ventilation and conditioning of a great amount of air flow. That is, there are disposed a humidity separator, a filter, a heater, a catalyst filled layer, a water jetting type humidifying heat insulation cooler and a cooler in this order from an inlet side (upstream) of contaminated room atmospheric gases. The catalyst filled layer, etc. are incorporated integrally into the ventilation air conditioning facility for ventilating air in the chamber of the thermonuclear reactor, to clean a tritium atmosphere at the same time. Accordingly, the device is made compact as a whole. A limit for the air flow rate owing to the use of the conventional catalyst tower and adsorbing tower is eliminated. Then a ventilating air conditioning for a great flow rate can be attained. Tritium is removed by cooling and dehumidification without using any adsorbent. Accordingly, an adsorbing tower is no more necessary and conventional regeneration operation is not required. As a result, space for installation is reduced, the system is simplified and the cost for construction and facility can be reduced. (I.S.)

  9. Experimental performance study of a proposed desiccant based air conditioning system.

    Science.gov (United States)

    Bassuoni, M M

    2014-01-01

    An experimental investigation on the performance of a proposed hybrid desiccant based air conditioning system referred as HDBAC is introduced in this paper. HDBAC is mainly consisted of a liquid desiccant dehumidification unit integrated with a vapor compression system (VCS). The VCS unit has a cooling capacity of 5.27 kW and uses 134a as refrigerant. Calcium chloride (CaCl2) solution is used as the working desiccant material. HDBAC system is used to serve low sensible heat factor applications. The effect of different parameters such as, process air flow rate, desiccant solution flow rate, evaporator box and condenser box solution temperatures, strong solution concentration and regeneration temperature on the performance of the system is studied. The performance of the system is evaluated using some parameters such as: the coefficient of performance (COPa), specific moisture removal and energy saving percentage. A remarkable increase of about 54% in the coefficient of performance of the proposed system over VCS with reheat is achieved. A maximum overall energy saving of about 46% is observed which emphasizes the use of the proposed system as an energy efficient air conditioning system.

  10. Fault diagnosis of air conditioning systems based on qualitative bond graph

    International Nuclear Information System (INIS)

    Ghiaus, C.

    1999-01-01

    The bond graph method represents a unified approach for modeling engineering systems. The main idea is that power transfer bonds the components of a system. The bond graph model is the same for both quantitative representation, in which parameters have numerical values, and qualitative approach, in which they are classified qualitatively. To infer the cause of faults using a qualitative method, a system of qualitative equations must be solved. However, the characteristics of qualitative operators require specific methods for solving systems of equations having qualitative variables. This paper proposes both a method for recursively solving the qualitative system of equations derived from bond graph, and a bond graph model of a direct-expansion, mechanical vapor-compression air conditioning system. Results from diagnosing two faults in a real air conditioning system are presented and discussed. Occasionally, more than one fault candidate is inferred for the same set of qualitative values derived from measurements. In these cases, additional information is required to localize the fault. Fault diagnosis is initiated by a fault detection mechanism which also classifies the quantitative measurements into qualitative values; the fault detection is not presented here. (author)

  11. Emissions of halocarbons from mobile vehicle air conditioning system in Hong Kong.

    Science.gov (United States)

    Yan, H H; Guo, H; Ou, J M

    2014-08-15

    During the implementation of Montreal Protocol, emission inventories of halocarbons in different sectors at regional scale are fundamental to the formulation of relevant management strategy and inspection of the implementation efficiency. This study investigated the emission profile of halocarbons used in the mobile vehicle air conditioning system, the leading sector of refrigeration industry in terms of the refrigerant bank, market and emission, in the Hong Kong Special Administrative Region, using a bottom-up approach developed by 2006 IPCC Good Practice Guidance. The results showed that emissions of CFC-12 peaked at 53 tons ODP (Ozone Depletion Potential) in 1992 and then gradually diminished, whereas HFC-134a presented an increasing emission trend since 1990s and the emissions of HFC-134a reached 65,000 tons CO2-equivelant (CO2-eq) by the end of 2011. Uncertainty analysis revealed relatively high levels of uncertainties for special-purpose vehicles and government vehicles. Moreover, greenhouse gas (GHG) abatements under different scenarios indicated that potential emission reduction of HFC-134a ranged from 4.1 to 8.4 × 10(5)tons CO2-eq. The findings in this study advance our knowledge of halocarbon emissions from mobile vehicle air conditioning system in Hong Kong. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. FY1999 Meeting of The Society of Heating, Air-Conditioning and Sanitary Engineering of Japan. Air conditioning systems for various facilities; 1999 nendo gakujutsu koenkai gaiyo. Kakushu shisetsu kucho system

    Energy Technology Data Exchange (ETDEWEB)

    Iwamoto, K. [Takenaka Corp., Osaka (Japan)

    1999-12-05

    B-49 reported the outline of an artificial weather room composed of one inner room and two outer rooms, and its temperature change and temperature profiles during air conditioning. The room is scheduled to be used for evaluation of air conditioning systems, thermal performance evaluation of building materials and study on ventilation efficiency. B-50 reported the seasonal measurement results on thermal environment, and cooling and heating use patterns of living rooms and common spaces of 4 welfare homes for aged persons, and showed that room temperature difference in winter should be considered. Measurement data on facilities with floor heating were required. B-51 reported the experiment and numerical analysis results on thermal environment, draft sensation, condensation and radiation effect of patient bedrooms by using a full-scale 4-bed room model with a specific outlet developed for patient bedroom air conditioning. B-52 reported the outline of an air conditioning system for vegetable factories, and its performance evaluation result during cooling. The effect of blackout curtains and local air conditioning was reported. B-53 reported the comparison study result on air conditioning for animal breeding rooms by full-scale model experiment and numerical analysis. The line outlet + hanging wall + rack back exhaust system was most favorable from the viewpoint of temperature profile and prevention of pollutants from diffusion. (translated by NEDO)

  13. Impact of surface disinfection and sterile draping of furniture on room air quality in a cardiac procedure room with a ventilation and air-conditioning system (extrusion airflow, cleanroom class 1b (DIN 1946-4)).

    Science.gov (United States)

    Below, Harald; Ryll, Sylvia; Empen, Klaus; Dornquast, Tina; Felix, Stefan; Rosenau, Heike; Kramer, Sebastian; Kramer, Axel

    2010-09-21

    In a cardiac procedure room, ventilated by a ventilation and air-conditioning system with turbulent mixed airflow, a protection zone in the operating area could be defined through visualization of airflows. Within this protection zone, no turbulence was detectable in the room air.Under the given conditions, disinfection of all surfaces including all furniture and equipment after the last operation and subsequent draping of furniture and all equipment that could not be removed from the room with sterile surgical drapes improved the indoor room air quality from cleanroom class C to cleanroom class B. This also allows procedures with elevated requirements to be performed in room class 1b.

  14. Seismic and dynamic qualification of safety-related electrical and mechanical equipment in operating nuclear power plants: development of a method to generate generic floor-response spectra

    International Nuclear Information System (INIS)

    Curreri, J.; Costantino, C.; Subudhi, M.; Reich, M.

    1983-09-01

    Generic floor response spectra were developed for use in the qualification of electrical and mechanical equipment in operating nuclear power plants. The characteristics of 1000 floor response spectra were studied to determine the generic spectra. The procedure developed uses as much or as little information that currently exists at the plant relating to the question of equipment qualification. The general approach was to study the effects on the dynamic characteristics of each of the elements in the chain of events that goes between the loads and the responses. This includes the loads, the soils and the structures. A free-field earthquake response spectra was used to generate horizontal earthquake time histories. The excitation was applied through the soil and into the various structures to produce responses in equipment. An entire range of soil conditions was used with each structure. Actual PWR and BWR - Mark I structural models were used. For each model, the stiffness properties were varied, with the same mass, so as to extend the fundamental base structure natural frequency from 2 cps to 36 cps. The natural frequencies of the structures were varied to obtain maximum response conditions. The actual properties were first used to locate the natural frequencies. The stiffness properties were than varied, with the same mass, to extend the range of the fundamental base structure natural frequency. The intention was to have the coupled structural material frequencies in the vicinity of the peak amplitude frequency content of the excitation spectrum. Particular attention was therefore given to the frequency band between 2 Hz and 4 Hz. A horizontal generic floor response spectra is proposed for the top level of a generic structure. Reduction factors are applied to the peak acceleration for equipment at lower levels

  15. The Histoty of Ventilation and Air Conditioning is CERN Up to Date with the latest Technological Developments?

    CERN Document Server

    Kühnl-Kinel, J

    2000-01-01

    The invention of ventilation cannot be ascribed to a certain date. It started with simple aeration when man brought fire into his abode and continued through different stages including air cooling using ice to finally arrive at the time when ventilation and air conditioning has become an essential part of our life and plays an important role in human evolution. This paper presents the history of ventilation and air conditioning, explains the key constraints over the centuries, and shows its influence on everyday life. Some examples of previous air-conditioning plants are described and different approaches to the way of calculation of ventilation systems discussed. It gives an overview of the Heating, Ventilation and Air Conditioning (HVAC) installations at CERN and points out their particularities. It also compares them with the latest technological developments in the field as well as showing the new trends that are being applied at CERN.

  16. Heating, Ventilation, Air Conditioning, and Refrigeration (HVAC/R), AFSC 3E1X1. OSSN 2368

    National Research Council Canada - National Science Library

    1999-01-01

    Survey Coverage: The Heating, Ventilation, Air Conditioning, and Refrigeration (HVAC/R) career ladder, AFSC 3E1X1, was surveyed to gather data needed to guide the development and evaluation of training...

  17. A vapor generator equipped with an advanced drain device for the secondary side of the tubes plate

    International Nuclear Information System (INIS)

    Valadon, C.

    1995-01-01

    A draining design is proposed for the tube plate secondary side in a PWR type reactor, that does not interfere with the water flush 'street' thus allowing for an easy inspection and maintenance in the lower part of the tube bundle. The draining system is composed of a main groove on the upper side of the tube plate, which is connected to draining means situated outside the vapor generator. 6 fig

  18. Performance assessment and transient optimization of air precooling in multi-stage solid desiccant air conditioning systems

    International Nuclear Information System (INIS)

    Gadalla, Mohamed; Saghafifar, Mohammad

    2016-01-01

    Highlights: • Studying three two-stage solid desiccant cooling systems using Maisotsenko cooler. • Proposing precooling to improve two-stage desiccant systems’ COP for humid climates. • Performing transient analysis for a two-stage solid desiccant cooler in UAE. • Optimizing daily performance of a two-stage solid desiccant cooler for UAE. - Abstract: Renewable energy is one of the most promising solutions to both energy and global warming crisis. Energy consumption can be minimized considerably by utilizing solar energy in air conditioning systems operation. One of the popular solar air conditioning technologies is desiccant air conditioning. Nonetheless, conventional desiccant air conditioning systems have a relatively low coefficient of performance (COP). In consequence, two-stage desiccant air-conditioning systems are proposed to improve desiccant air conditioning systems’ COP. Moreover, a recently commercialized cooling method named Maisotsenko cooling cycle which is capable of cooling air near to its dew point temperature is considered to be integrated within the proposed multi-stage desiccant cooling systems. In this paper, three new two-stage desiccant air conditioning systems incorporating Maisotsenko cooling cycle are proposed and investigated in details for hot and humid climates such as UAE. Furthermore, air precooling is considered to improve two stage desiccant air conditioning systems’ COP. Moreover, full transient analysis and optimization are carried out in UAE within June–October. The proposed system can minimize the required solar heating during noon time as the ambient air dry bulb temperature rises. Average COP of the system during electricity load peak hours (10:00–14:00) for all five considered and combined months is 1.77. Average rate of heat input required to operate the system and average building cooling load are determined to be 100.3 kW and 46.2 kW, respectively. Therefore, system average COP is computed to be 0.46.

  19. The Histoty of Ventilation and Air Conditioning: is CERN Up to Date with the latest Technological Developments?

    OpenAIRE

    Kühnl-Kinel, J

    2000-01-01

    The invention of ventilation cannot be ascribed to a certain date. It started with simple aeration when man brought fire into his abode and continued through different stages including air cooling using ice to finally arrive at the time when ventilation and air conditioning has become an essential part of our life and plays an important role in human evolution. This paper presents the history of ventilation and air conditioning, explains the key constraints over the centuries, and shows its i...

  20. Development of simulation technology on full auto air conditioning system; Auto eakon no simulation gijutsu no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, N; Otsubo, Y; Matsumura, K; Sako, H [Mazda Motor Corp., Hiroshima (Japan)

    1997-10-01

    Mazda has developed simulation technology on control of full auto air conditioning system. We have developed the development tool based on the technology, aiming at higher controllability of full auto air conditioning system and shorter development period. The tool performs simulation on control, on-vehicle evaluation of actual load operation, collecting data and analyzing them by personal computer. This paper reports our verification results on effectiveness of the technology/ and the tool. 4 refs., 9 figs.

  1. Effectiveness of photocatalytic filter for removing volatile organic compounds in the heating, ventilation, and air conditioning system.

    Science.gov (United States)

    Yu, Kuo-Pin; Lee, Grace Whei-May; Huang, Wei-Ming; Wu, Chih-Cheng; Lou, Chia-ling; Yang, Shinhao

    2006-05-01

    Nowadays, the heating, ventilation, and air conditioning (HVAC) system has been an important facility for maintaining indoor air quality. However, the primary function of typical HVAC systems is to control the temperature and humidity of the supply air. Most indoor air pollutants, such as volatile organic compounds (VOCs), cannot be removed by typical HVAC systems. Thus, some air handling units for removing VOCs should be added in typical HVAC systems. Among all of the air cleaning techniques used to remove indoor VOCs, photocatalytic oxidation is an attractive alternative technique for indoor air purification and deodorization. The objective of this research is to investigate the VOC removal efficiency of the photocatalytic filter in a HVAC system. Toluene and formaldehyde were chosen as the target pollutants. The experiments were conducted in a stainless steel chamber equipped with a simplified HVAC system. A mechanical filter coated with Degussa P25 titania photocatalyst and two commercial photocatalytic filters were used as the photocatalytic filters in this simplified HVAC system. The total air change rates were controlled at 0.5, 0.75, 1, 1.25, and 1.5 hr(-1), and the relative humidity (RH) was controlled at 30%, 50%, and 70%. The ultraviolet lamp used was a 4-W, ultraviolet-C (central wavelength at 254 nm) strip light bulb. The first-order decay constant of toluene and formaldehyde found in this study ranged from 0.381 to 1.01 hr(-1) under different total air change rates, from 0.34 to 0.433 hr(-1) under different RH, and from 0.381 to 0.433 hr(-1) for different photocatalytic filters.

  2. Impact of Solar Control PVB Glass on Vehicle Interior Temperatures, Air-Conditioning Capacity, Fuel Consumption, and Vehicle Range

    Energy Technology Data Exchange (ETDEWEB)

    Rugh, J.; Chaney, L.; Venson, T.; Ramroth, L.; Rose, M.

    2013-04-01

    The objective of the study was to assess the impact of Saflex1 S-series Solar Control PVB (polyvinyl butyral) configurations on conventional vehicle fuel economy and electric vehicle (EV) range. The approach included outdoor vehicle thermal soak testing, RadTherm cool-down analysis, and vehicle simulations. Thermal soak tests were conducted at the National Renewable Energy Laboratory's Vehicle Testing and Integration Facility in Golden, Colorado. The test results quantified interior temperature reductions and were used to generate initial conditions for the RadTherm cool-down analysis. The RadTherm model determined the potential reduction in air-conditioning (A/C) capacity, which was used to calculate the A/C load for the vehicle simulations. The vehicle simulation tool identified the potential reduction in fuel consumption or improvement in EV range between a baseline and modified configurations for the city and highway drive cycles. The thermal analysis determined a potential 4.0% reduction in A/C power for the Saflex Solar PVB solar control configuration. The reduction in A/C power improved the vehicle range of EVs and fuel economy of conventional vehicles and plug-in hybrid electric vehicles.

  3. Equipment for secondary water distribution in heat exchanger, especially saturated steam generator for nuclear power plants and heat plants

    Energy Technology Data Exchange (ETDEWEB)

    Riman, J; Manek, O; Rybnicek, J

    1979-09-15

    A special structure consisting of a system of channels and a distribution plate with ports in-built above the tube-plate of a vertical-type steam generator prevents secondary water vaporization in the space above the tube-plate and thus also salt and sludge sedimentation which causes increased corrosion of heat transfer tubes. The size of the distribution plate ports is variable in the radial direction. The distribution plate is divided by means of the system of channels into at least two parts. The middle section of each part is of the through-flow type.

  4. Physiological and subjective responses in the elderly when using floor heating and air conditioning systems.

    Science.gov (United States)

    Hashiguchi, Nobuko; Tochihara, Yutaka; Ohnaka, Tadakatsu; Tsuchida, Chiaki; Otsuki, Tamio

    2004-11-01

    The purpose of this study was to investigate the effects of a floor heating and air conditioning system on thermal responses of the elderly. Eight elderly men and eight university students sat for 90 minutes in a chair under the following 3 conditions: air conditioning system (A), floor heating system (F) and no heating system (C). The air temperature of sitting head height for condition A was 25 degrees C, and the maximum difference in vertical air temperature was 4 degrees C. The air and floor temperature for condition F were 21 and 29 degrees C, respectively. The air temperature for condition C was 15 degrees C. There were no significant differences in rectal temperature and mean skin temperature between condition A and F. Systolic blood pressure of the elderly men in condition C significantly increased compared to those in condition A and F. No significant differences in systolic blood pressure between condition A and F were found. The percentage of subjects who felt comfortable under condition F was higher than that of those under condition A in both age groups, though the differences between condition F and A was not significant. Relationships between thermal comfort and peripheral (e.g., instep, calf, hand) skin temperature, and the relationship between thermal comfort and leg thermal sensation were significant for both age groups. However, the back and chest skin temperature and back thermal sensation for the elderly, in contrast to that for the young, was not significantly related to thermal comfort. These findings suggested that thermal responses and physiological strain using the floor heating system did not significantly differ from that using the air conditioning system, regardless of the subject age and despite the fact that the air temperature with the floor heating system was lower. An increase in BP for elderly was observed under the condition in which the air temperature was 15 degrees C, and it was suggested that it was necessary for the elderly

  5. General collaboration offer of Johnson Controls regarding the performance of air conditioning automatic control systems and other buildings` automatic control systems

    Energy Technology Data Exchange (ETDEWEB)

    Gniazdowski, J.

    1995-12-31

    JOHNSON CONTROLS manufactures measuring and control equipment (800 types) and is as well a {open_quotes}turn-key{close_quotes} supplier of complete automatic controls systems for heating, air conditioning, ventilation and refrigerating engineering branches. The Company also supplies Buildings` Computer-Based Supervision and Monitoring Systems that may be applied in both small and large structures. Since 1990 the company has been performing full-range trade and contracting activities on the Polish market. We have our own well-trained technical staff and we collaborate with a series of designing and contracting enterprises that enable us to have our projects carried out all over Poland. The prices of our supplies and services correspond with the level of the Polish market.

  6. Parametric performance analysis of a concentrated photovoltaic co-generation system equipped with a thermal storage tank

    International Nuclear Information System (INIS)

    Imtiaz Hussain, M.; Lee, Gwi Hyun

    2015-01-01

    Highlights: • Both thermal and electrical powers varied by changing surface area of collector. • Thermal stratification and total system power were increased at critical flow rate. • Parametric analysis of the CPVC system offers to determine the desired outcome. • Thermal and electrical outputs varied by changing the focal length of Fresnel lens. - Abstract: This article presents a parametric study of a concentrated photovoltaic co-generation (CPVC) system with an attached thermal storage tank. The CPVC system utilized dual-axis tracker and multiple solar energy collector (SEC) modules and forced cooling system. Each SEC module comprised 16 triple-junction solar cells, copper tube absorbers, and 16 Fresnel lenses were aligned against each solar cell. This study investigated all possible parameters that can affect the CPVC system performance, including the collector area, solar irradiation, inlet temperature, and mass flow rate. The surface area of the collector and the thermal power were increased by increasing the number of SEC modules connected in series; however, the electrical power output decreased from the first to the fourth SEC module consecutively. At the measured optimal flow rate, mixing and thermal diffusion in the storage tank were decreased, and the total power generation from the CPVC system was increased. Variations in the thermal and electrical power outputs were also observed when the focal length of the Fresnel lens was changed. This parametric analysis enables the CPVC system to obtain the desired output by varying the combination of operational and geometrical parameters

  7. Exergy characteristics of a ceiling-type residential air conditioning system operating under different climatic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ozbek, Arif [Dept. of Mechanical Engineering, Ceyhan Engineering Faculty, Cukurova University, Adana (Turkmenistan)

    2016-11-15

    In this study an energy and exergy analysis of a Ceiling-type residential air conditioning (CTRAC) system operating under different climatic conditions have been investigated for provinces within the different geographic regions of Turkey. Primarily, the hourly cooling load capacities of a sample building (Q{sub evap}) during the months of April, May, June, July, August and September were determined. The hourly total heat gain of the sample building was determined using the Hourly analysis program (HAP). The Coefficient of performance (COP), exergy efficiency (η) and exergy destruction (Ex{sub dest}) values for the whole system and for each component were obtained. The results showed that lower atmospheric temperature (T{sub atm}) influenced the performance of the system and each of its components.

  8. THERMAL COMFORT STUDY OF AN AIR-CONDITIONED DESIGN STUDIO IN TROPICAL SURABAYA

    Directory of Open Access Journals (Sweden)

    Agus Dwi Hariyanto

    2005-01-01

    Full Text Available This paper evaluates the current thermal comfort condition in an air-conditioned design studio using objective measurement and subjective assessment. Objective measurement is mainly to quantify the air temperature, MRT, relative humidity, and air velocity. Subjective assessment is conducted using a questionnaire to determine the occupants thermal comfort sensations and investigate their perception of the thermal comfort level. A design studio in an academic institution in Surabaya was chosen for the study. Results show that more than 80% of the occupants accepted the indoor thermal conditions even though both the environmental and comfort indices exceeded the limit of the standard (ASHRAE Standard 55 and ISO 7730. In addition, non-uniformity of spatial temperature was present in this studio. Some practical recommendations were made to improve the thermal comfort in the design studio.

  9. Development of salt hydrate eutectics as latent heat storage for air conditioning and cooling

    International Nuclear Information System (INIS)

    Efimova, Anastasia; Pinnau, Sebastian; Mischke, Matthias; Breitkopf, Cornelia; Ruck, Michael; Schmidt, Peer

    2014-01-01

    Graphical abstract: - Highlights: • Inorganic salt hydrates. • Latent heat thermal energy storage. • Thermal behavior of melting and crystallization. • Cycling stability. • Nucleation. - Abstract: Sustainable air conditioning systems require heat reservoirs that operate between 4 and 20 °C. A systematic search for binary and ternary eutectics of inorganic salts and salt hydrates with melting temperatures in this temperature regime and with high enthalpies of fusion has been performed by means of differential scanning calorimetry (DSC). Promising results were obtained for the pseudo-ternary system Zn(NO 3 ) 2 ·6H 2 O, Mn(NO 3 ) 2 ·4H 2 O, and KNO 3 with the melting temperature range 18–21 °C and the enthalpy of fusion of about 110 kJ kg −1 . Suitable nucleating and thickening agents have been found and tested to prevent the mixture from supercooling and phase separation

  10. Absorber and regenerator models for liquid desiccant air conditioning systems. Validation and comparison using experimental data

    Energy Technology Data Exchange (ETDEWEB)

    Krause, M.; Heinzen, R.; Jordan, U.; Vajen, K. [Kassel Univ., Inst. of Thermal Engineering, Kassel (Germany); Saman, W.; Halawa, E. [Sustainable Energy Centre, Univ. of South Australia, Mawson Lakes, Adelaide (Australia)

    2008-07-01

    Solar assisted air conditioning systems using liquid desiccants represent a promising option to decrease high summer energy demand caused by electrically driven vapor compression machines. The main components of liquid desiccant systems are absorbers for dehumidifying and cooling of supply air and regenerators for concentrating the desiccant. However, high efficient and validated reliable components are required and the design and operation have to be adjusted to each respective building design, location, and user demand. Simulation tools can help to optimize component and system design. The present paper presents new developed numerical models for absorbers and regenerators, as well as experimental data of a regenerator prototype. The models have been compared with a finite-difference method model as well as experimental data. The data are gained from the regenerator prototype presented and an absorber presented in the literature. (orig.)

  11. Application of a solar refrigeration system by absorption for the air conditioning of buildings

    Energy Technology Data Exchange (ETDEWEB)

    Machielsen, Cees H. M [Delft University of Technology, Mekelweg (Netherlands); Hagendijk, Andre E [Consultancy and Research (Netherlands)

    2000-07-01

    This paper describes the Sofri project, a cooperation between Ceeran Ltd and The Delft University of Technology. The main objective of this project is to develop the necessary knowledge and experience to commercialize solar-assisted air conditioning and dehumidification systems in the Dutch Caribbean. The project is motivated by the present needs of the Dutch Caribbean for renewable energy sources and the fact that the Caribbean has a high and uniform insolation throughout the year. Furthermore, hotels and offices in this area use more than 40% of their energy for air-conditioning purposes. Therefore solar-assisted air conditioning systems are a logic approach in reducing the energy demand and to lower the peak electricity reducing the energy demands for the local power station. Ceeran Ltd has the objective to reach full commercialization of the proposed technologies in the Dutch Caribbean. The research is concentrated on liquid absorption machines and solar collection systems such as flat plates with selective surfaces, heat pipe evacuated tubes flat plate collectors, and Compound Parabolic Concentrators. The first demonstration unit is planned to be installed in an office building in Curacao. The installation consists of a 35 kW LiBr/H{sub 2}O absorption machine driven by 100 m{sup 2} flat pate collectors with a gas backup system. The system will provide comfort air-conditioning for this these type of office buildings during daytime. [Spanish] Este documento describe el proyecto SOFRI, una cooperacion entre Ceeran, Ltd, y la Universidad Tecnologica del Delft. El principal objetivo de este proyecto es el de desarrollar el conocimiento necesario y la experiencia para comercializar los sistemas de aire acondicionado y deshumidificacion ayudados por la energia solar en el Caribe Holandes. Este proyecto ha sido motivado por las actuales necesidades del Caribe Holandes de fuentes de energia renovable y por el hecho de que el Caribe tiene una alta y uniforme insolacion

  12. Japanese power electronics inverter technology and its impact on the American air conditioning industry

    Science.gov (United States)

    Ushimaru, Kenji

    1990-08-01

    Since 1983, technological advances and market growth of inverter-driven variable-speed heat pumps in Japan have been dramatic. The high level of market penetration was promoted by a combination of political, economic, and trade policies in Japan. A unique environment was created in which the leading domestic industries, microprocessor manufacturing, compressors for air conditioning and refrigerators, and power electronic devices, were able to direct the development and market success of inverter-driven heat pumps. As a result, leading U.S. variable-speed heat pump manufacturers should expect a challenge from the Japanese producers of power devices and microprocessors. Because of the vertically-integrated production structure in Japan, in contrast to the out-sourcing culture of the United States, price competition at the component level (such as inverters, sensors, and controls) may impact the structure of the industry more severely than final product sales.

  13. Japanese power electronics inverter technology and its impact on the American air conditioning industry

    Energy Technology Data Exchange (ETDEWEB)

    Ushimaru, Kenji.

    1990-08-01

    Since 1983, technological advances and market growth of inverter- driven variable-speed heat pumps in Japan have been dramatic. The high level of market penetration was promoted by a combination of political, economic, and trade policies in Japan. A unique environment was created in which the leading domestic industries-- microprocessor manufacturing, compressors for air conditioning and refrigerators, and power electronic devices--were able to direct the development and market success of inverter-driven heat pumps. As a result, leading US variable-speed heat pump manufacturers should expect a challenge from the Japanese producers of power devices and microprocessors. Because of the vertically-integrated production structure in Japan, in contrast to the out-sourcing culture of the United States, price competition at the component level (such as inverters, sensors, and controls) may impact the structure of the industry more severely than final product sales. 54 refs., 47 figs., 1 tab.

  14. Optimization of recirculating laminar air flow in operating room air conditioning systems

    Directory of Open Access Journals (Sweden)

    Enver Yalcin

    2016-04-01

    Full Text Available The laminar flow air-conditioning system with 100% fresh air is used in almost all operating rooms without discrimination in Turkey. The laminar flow device which is working with 100% fresh air should be absolutely used in Type 1A operating rooms. However, there is not mandatory to use of 100% fresh air for Type 1B defined as places performed simpler operation. Compared with recirculating laminar flow, energy needs of the laminar flow with 100 % fresh air has been emerged about 40% more than re-circulated air flow. Therefore, when a recirculating laminar flow device is operated instead of laminar flow system with 100% fresh air in the Type 1B operating room, annual energy consumption will be reduced. In this study, in an operating room with recirculating laminar flow, optimal conditions have been investigated in order to obtain laminar flow form by analyzing velocity distributions at various supply velocities by using computational fluid dynamics method (CFD.

  15. LiCl Dehumidifier LiBr absorption chiller hybrid air conditioning system with energy recovery

    Science.gov (United States)

    Ko, Suk M.

    1980-01-01

    This invention relates to a hybrid air conditioning system that combines a solar powered LiCl dehumidifier with a LiBr absorption chiller. The desiccant dehumidifier removes the latent load by absorbing moisture from the air, and the sensible load is removed by the absorption chiller. The desiccant dehumidifier is coupled to a regenerator and the desiccant in the regenerator is heated by solar heated hot water to drive the moisture therefrom before being fed back to the dehumidifier. The heat of vaporization expended in the desiccant regenerator is recovered and used to partially preheat the driving fluid of the absorption chiller, thus substantially improving the overall COP of the hybrid system.

  16. Study and Development of an Air Conditioning System Operating on a Magnetic Heat Pump Cycle

    Science.gov (United States)

    Wang, Pao-Lien

    1991-01-01

    This report describes the design of a laboratory scale demonstration prototype of an air conditioning system operating on a magnetic heat pump cycle. Design parameters were selected through studies performed by a Kennedy Space Center (KSC) System Simulation Computer Model. The heat pump consists of a rotor turning through four magnetic fields that are created by permanent magnets. Gadolinium was selected as the working material for this demonstration prototype. The rotor was designed to be constructed of flat parallel disks of gadolinium with very little space in between. The rotor rotates in an aluminum housing. The laboratory scale demonstration prototype is designed to provide a theoretical Carnot Cycle efficiency of 62 percent and a Coefficient of Performance of 16.55.

  17. Optimal heat rejection pressure in transcritical carbon dioxide air conditioning and heat pump systems

    DEFF Research Database (Denmark)

    Liao, Shengming; Jakobsen, Arne

    1998-01-01

    Due to the urgent need for environmentally benign refrigerants, the use of the natural substance carbon dioxide in refrigeration systems has gained more and more attention. In systems such as automobile air-conditioners and heat pumps, owing to the relatively high heat rejection temperatures, the...... dioxide air conditioning or heat pump systems and for intelligent controlling such systems.......Due to the urgent need for environmentally benign refrigerants, the use of the natural substance carbon dioxide in refrigeration systems has gained more and more attention. In systems such as automobile air-conditioners and heat pumps, owing to the relatively high heat rejection temperatures......, the cycles using carbon dioxide as refrigerant will have to operate in the transcritical area. In a transcritical carbon dioxide system, there is an optimal heat rejection pressure that gives a maximum COP. In this paper, it is shown that the value of this optimal heat rejection pressure mainly depends...

  18. Performance of residential air-conditioning systems with flow maldistribution in fin-and-tube evaporators

    DEFF Research Database (Denmark)

    Kærn, Martin Ryhl; Brix, Wiebke; Elmegaard, Brian

    2011-01-01

    Refrigerant and airflow maldistribution in fin-and-tube evaporators for residential air-conditioning was investigated with numerical modeling. Fin-and-tube heat exchangers usually have a pre-defined circuitry. However, the objective in this study was to perform a generic investigation of each...... individual maldistribution source in an independent manner. Therefore, the evaporator and the condenser were simplified to be straight tubes for the purposes of this study. The numerical model of the R410A system, its verification and an investigation of individual maldistribution sources are presented...... in this paper. The maldistribution sources of interest were: inlet liquid/vapor phase distribution, feeder tube bending and airflow distribution. The results show that maldistribution reduced the cooling capacity and the coefficient of performance of the system. In particular, different phase distribution...

  19. Life cycle assessment of a conventional and plastic solar collector in alternative air-conditioning

    International Nuclear Information System (INIS)

    Algarbi, N. M.

    2006-01-01

    Alternative solar systems include a large number of heat-and mass exchange apparatus (HMTA) with considerable size surfaces. Prequired for realization of the work processes. This result in the increase in the overall dimentions. and cost of the system. The possibility of using the principle of combining the working and auxiliary processes within the (HMTA) has been considred, and the calculation proving the working ability of the alternative system for solving the task of air-condition, obtaining comfort parameters by employing evaporative air-cooling methods only, and a solar system with flat solar collectors to provide for the absorbent regeneration, have been performed. The study shows the importance in using Live Cycle Assessment, study for renewable energy, technologies, where environmental performance is especially important.(Author)

  20. Evaluation Framework and Analyses for Thermal Energy Storage Integrated with Packaged Air Conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Kung, F.; Deru, M.; Bonnema, E.

    2013-10-01

    Few third-party guidance documents or tools are available for evaluating thermal energy storage (TES) integrated with packaged air conditioning (AC), as this type of TES is relatively new compared to TES integrated with chillers or hot water systems. To address this gap, researchers at the National Renewable Energy Laboratory conducted a project to improve the ability of potential technology adopters to evaluate TES technologies. Major project outcomes included: development of an evaluation framework to describe key metrics, methodologies, and issues to consider when assessing the performance of TES systems integrated with packaged AC; application of multiple concepts from the evaluation framework to analyze performance data from four demonstration sites; and production of a new simulation capability that enables modeling of TES integrated with packaged AC in EnergyPlus. This report includes the evaluation framework and analysis results from the project.

  1. Modeling of a New Structure of Precision Air Conditioning System Using Secondary Condenser for Rh Regulation

    Directory of Open Access Journals (Sweden)

    Aries Subiantoro

    2012-05-01

    Full Text Available A dynamic mathematical model for a new structure of precision air conditioning (PAC has been developed. The proposed PAC uses an additional secondary condenser for relative humidity regulation compared to a basic refrigeration system. The work mechanism for this system and a vapour-compression cycle process of the system are illustrated using psychrometric chart and pressure-enthalpy diagram. A non-linear system model is derived based on the conservation of mass and energy balance principles and then linearized at steady state operating point for developing a 8th-order state space model suited for multivariable controller design. The quality of linearized model is analyzed in terms of transient response, controllability, observability, and interaction between input-output variables. The developed model is verified through simulation showing its ability for imitating the nonlinear behavior and the interaction of input-output variables.

  2. Comparative study of air conditioning systems with vapor compression chillers using the concept of green buildings

    Directory of Open Access Journals (Sweden)

    Gutenberg da Silva Pereira

    2015-10-01

    Full Text Available This paper sets out to compare two different cooling systems that use vapor compression chillers for air conditioning environments. It was proposed to compare different operations in isolated and combined action operations. These operations are evaluated in the concepts of green buildings. A mathematical model was developed based on the principles of mass and energy conservation and complemented by various functions so as to determine the thermophysical properties and efficiencies of the compressors. The equations of the model were solved by the EES (Engineering Equation Solver program. The model evaluates the influence of the main HVAC operating parameters of the chilled water system when operating under three different configurations. The results showed that the system with a differentiated compression presents a COP equal to that of the system with screw chillers in the range  0-300 RTs, and a COP hat is on average 9% higher in the range 400-800 RTs.

  3. Emissions of halocarbons from mobile vehicle air conditioning system in Hong Kong

    International Nuclear Information System (INIS)

    Yan, H.H.; Guo, H.; Ou, J.M.

    2014-01-01

    Highlights: • Halocarbon emissions from MVACS were characterized using bottom up approach. • Quantification of emission inventory was revealed using AUV Tools. • Potential emission reduction was estimated under 3 possible mitigation scenarios. • The results are useful for the policy makers to formulate and implement future phase-out schedule. - Abstract: During the implementation of Montreal Protocol, emission inventories of halocarbons in different sectors at regional scale are fundamental to the formulation of relevant management strategy and inspection of the implementation efficiency. This study investigated the emission profile of halocarbons used in the mobile vehicle air conditioning system, the leading sector of refrigeration industry in terms of the refrigerant bank, market and emission, in the Hong Kong Special Administrative Region, using a bottom-up approach developed by 2006 IPCC Good Practice Guidance. The results showed that emissions of CFC-12 peaked at 53 tons ODP (Ozone Depletion Potential) in 1992 and then gradually diminished, whereas HFC-134a presented an increasing emission trend since 1990s and the emissions of HFC-134a reached 65,000 tons CO 2 -equivelant (CO 2 -eq) by the end of 2011. Uncertainty analysis revealed relatively high levels of uncertainties for special-purpose vehicles and government vehicles. Moreover, greenhouse gas (GHG) abatements under different scenarios indicated that potential emission reduction of HFC-134a ranged from 4.1 to 8.4 × 10 5 tons CO 2 -eq. The findings in this study advance our knowledge of halocarbon emissions from mobile vehicle air conditioning system in Hong Kong

  4. Microbial communities related to volatile organic compound emission in automobile air conditioning units.

    Science.gov (United States)

    Diekmann, Nina; Burghartz, Melanie; Remus, Lars; Kaufholz, Anna-Lena; Nawrath, Thorben; Rohde, Manfred; Schulz, Stefan; Roselius, Louisa; Schaper, Jörg; Mamber, Oliver; Jahn, Dieter; Jahn, Martina

    2013-10-01

    During operation of mobile air conditioning (MAC) systems in automobiles, malodours can occur. We studied the microbial communities found on contaminated heat exchanger fins of 45 evaporators from car MAC systems which were operated in seven different regions of the world and identified corresponding volatile organic compounds. Collected biofilms were examined by scanning electron microscopy and fluorescent in situ hybridization. The detected bacteria were loosely attached to the metal surface. Further analyses of the bacteria using PCR-based single-strand conformation polymorphism and sequencing of isolated 16S rRNA gene fragments identified highly divergent microbial communities with multiple members of the Alphaproteobacteriales, Methylobacteria were the prevalent bacteria. In addition, Sphingomonadales, Burkholderiales, Bacillales, Alcanivorax spp. and Stenotrophomonas spp. were found among many others depending on the location the evaporators were operated. Interestingly, typical pathogenic bacteria related to air conditioning systems including Legionella spp. were not found. In order to determine the nature of the chemical compounds produced by the bacteria, the volatile organic compounds were examined by closed loop stripping analysis and identified by combined gas chromatography/mass spectrometry. Sulphur compounds, i.e. di-, tri- and multiple sulphides, acetylthiazole, aromatic compounds and diverse substituted pyrazines were detected. Mathematical clustering of the determined microbial community structures against their origin identified a European/American/Arabic cluster versus two mainly tropical Asian clusters. Interestingly, clustering of the determined volatiles against the origin of the corresponding MAC revealed a highly similar pattern. A close relationship of microbial community structure and resulting malodours to the climate and air quality at the location of MAC operation was concluded.

  5. Emissions of halocarbons from mobile vehicle air conditioning system in Hong Kong

    Energy Technology Data Exchange (ETDEWEB)

    Yan, H.H.; Guo, H., E-mail: ceguohai@polyu.edu.hk; Ou, J.M.

    2014-08-15

    Highlights: • Halocarbon emissions from MVACS were characterized using bottom up approach. • Quantification of emission inventory was revealed using AUV Tools. • Potential emission reduction was estimated under 3 possible mitigation scenarios. • The results are useful for the policy makers to formulate and implement future phase-out schedule. - Abstract: During the implementation of Montreal Protocol, emission inventories of halocarbons in different sectors at regional scale are fundamental to the formulation of relevant management strategy and inspection of the implementation efficiency. This study investigated the emission profile of halocarbons used in the mobile vehicle air conditioning system, the leading sector of refrigeration industry in terms of the refrigerant bank, market and emission, in the Hong Kong Special Administrative Region, using a bottom-up approach developed by 2006 IPCC Good Practice Guidance. The results showed that emissions of CFC-12 peaked at 53 tons ODP (Ozone Depletion Potential) in 1992 and then gradually diminished, whereas HFC-134a presented an increasing emission trend since 1990s and the emissions of HFC-134a reached 65,000 tons CO{sub 2}-equivelant (CO{sub 2}-eq) by the end of 2011. Uncertainty analysis revealed relatively high levels of uncertainties for special-purpose vehicles and government vehicles. Moreover, greenhouse gas (GHG) abatements under different scenarios indicated that potential emission reduction of HFC-134a ranged from 4.1 to 8.4 × 10{sup 5} tons CO{sub 2}-eq. The findings in this study advance our knowledge of halocarbon emissions from mobile vehicle air conditioning system in Hong Kong.

  6. Open absorption system for cooling and air conditioning using membrane contactors - Final report

    Energy Technology Data Exchange (ETDEWEB)

    Conde-Petit, M. [M. Conde Engineering, Zuerich (Switzerland); Weber, R.; Dorer, V. [Swiss Federal Laboratories for Materials Testing and Research (EMPA), Duebendorf (Switzerland)

    2008-07-01

    Air conditioning systems based upon the open absorption principle, essentially an absorption device operating at atmospheric pressure, have been proposed and investigated at many instances in the past eighty years. Their potential for improving energy efficiency is clearly recognized in the earliest research reports. By the mid 1950ies, solar thermal energy was being applied to drive open absorption-based air conditioning systems. For several reasons, however, the open absorption technology was not mature enough to take place in the mainstream. In the past two decades, vigorous efforts have been undertaken to reverse this situation, but success continued to elude, despite the fact that the main problems, such as corrosion, aerosols in the supply air, etc., have been identified. This report details the work and the main results from the MemProDEC Project. In this project innovative solutions were proposed, and successfully investigated, for the corrosion problem and the improvement of efficiency of the absorption process, in particular a new method to cool a very compact absorber. The practically uniform flow distribution for all three streams in the absorber (air, water and desiccant) warrants the contact of the air to be dehumidified with the desiccant over the whole surface of exchange (across a porous membrane). This, together with the cooling with water in counter flow to the air, are the key factors for the excellent effectiveness of the absorber. As the results show, the dehydration effectiveness of the prototype absorber is up to 150 % higher than that previously obtained by others. The solutions developed for compactness and modularity represent an important step in the way to flexible manufacturing, i.e. using a single element size to assemble autonomous air handling units of various nominal capacities. And although the manufacturing methods of the individual elements require improvement, namely by avoiding adhesive bonding, the choice of materials and the

  7. 2017 German refrigeration and air conditioning meeting. Proceedings; Deutsche Kaelte- und Klimatagung 2017. Tagungsbericht

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2017-07-01

    This year's lecture programme includes 117 presentations in the five working departments of DKV and 10 lectures at the special event ''Energy-efficient air conditioning in data centres''. The main topics in the respective departments were: (1) Cryogenics: Space applications; Cryogenic plants; Cryomedicine and cryobiology; Components, developments; Processes and plants; Valves, design. (2) Basics: Evaporation, material values; evaporation, condensation; absorption; adsorption, latent storage; cycle simulation. (3) Components: CO{sub 2} plant engineering and components; refrigerants; process control, adsorption, sublimation and storage technology; refrigerating machine oils, heat exchangers and corrosion; components 4.0, sensors and control technology; simulation of plant processes. (4) Cold application: Application; Application / Natural Refrigerants; Mobile Applications Car; Mobile Applications; Supermarket / Efficiency; Optimization / Efficiency. (5) Air conditioning and heat pump applications: load shifting, smart home, flexibility; heat sources and industrial heat pumps; modelling, simulations; energy concepts heat pumps and photovoltaics; monitoring, evaluation; technology trends / working materials. Six papers are separately analyzed for this database. [German] Das Vortragsprogramm umfasst in diesem Jahr 117 Beitraege in den fuenf Arbeitsabteilungen des DKV und 10 Vortraege in der Sonderveranstaltung ''Energieeffiziente Klimatisierung in Rechenzentren''. Die Hauptthemen in den jeweiligen Arbeitsabteilungen waren: (1) Kryotechnik: Raumfahrtanwendungen; Kryo-Grossanlagen; Kryomedizin und Kryobiologie; Komponenten, Entwicklungen; Verfahren und Anlagen; Ventile, Auslegung. (2) Grundlagen: Verdampfung, Stoffwerte; Verdampfung, Kondensation; Absorption; Adsorption, Latentspeicher; Kreislaufsimulation. (3) Komponenten: CO{sub 2}-Anlagentechnik und Komponenten; Kaeltemittel; Prozessfuehrung, Adsorption, Sublimation und

  8. Energy performance and optimal control of air-conditioned buildings with envelopes enhanced by phase change materials

    International Nuclear Information System (INIS)

    Zhu Na; Wang Shengwei; Ma Zhenjun; Sun Yongjun

    2011-01-01

    Highlights: → Impact of PCM on the energy consumption and peak load demand as well as electricity cost of air-conditioned buildings. → Impact of load shifting control on energy consumption, peak load and electricity cost of air-conditioned PCM buildings. → Impact of demand limiting control on energy consumption, peak load and electricity cost of air-conditioned PCM buildings. → Energy/cost effects of different control strategies and use of PCM in energy-plus-demand-based pricing policy. → Energy/cost effects of different control strategies and use of PCM in time-based pricing policy. - Abstract: Studies are conducted to investigate the impacts of shape-stabilized phase change material (SSPCM) and different control strategies on the energy consumption and peak load demand as well as electricity cost of building air-conditioning systems at typical summer conditions in two climates (subtropical and dry continental climates). An office building using a typical variable air volume (VAV) air-conditioning system was selected and simulated as the reference building in this study. Its envelopes were enhanced by integrating the SSPCM layers into its walls while the air-conditioning system and other configurations of the building remained unchanged. The building system was tested under two typical weather conditions and two typical electricity pricing policies (i.e. time-based pricing and energy-plus-demand-based pricing). Test results show that the use of SSPCM in the building could reduce the building electricity cost significantly (over 11% in electricity cost reduction and over 20% in peak load reduction), under two pricing policies by using load shifting control and demand limiting control respectively. This paper presents the test results and the evaluation on the energy performance and the optimal control strategies of air-conditioned commercial buildings with envelopes enhanced by SSPCM.

  9. Experimental and numerical study on thermal-hydraulic performance of wing-shaped-tubes-bundle equipped with winglet vortex generators

    Science.gov (United States)

    Abdelatief, Mohamed A.; Sayed Ahmed, Sayed Ahmed E.; Mesalhy, Osama M.

    2018-03-01

    The present work evaluates, experimentally and numerically, by the aid of commercial code FLUENT 6.3.26, the effects of relative locations (ΔX or ΔY), heights (hw), and span-angle (θ) of winglet-vortex-generators (WVGs) on thermal-hydraulic performance enhancement for down-stream and/or up-stream wing-shaped-tubes bundle heat exchangers for air Re ranging from 1.85 × 103 to 9.7 × 103 while water Re = 5 × 102. hw is set as 5 mm, 7.5 mm and 10 mm. For tube down-stream, θ is set as 0° (Base-line-case) and from 5° to 45° clockwise common-flow up (CFUp) and counterclockwise common-flow down (CFDn) while for tube up-stream it is set as -5°, -10° and -15° CFUp. Results show that the increase of θ counterclockwise-(CFDn) or clockwise-(CFUp) leads to increase the values of Nu number. Using WVGs with (+5 ° ≤ θ ≤ +45°) results in increasing Nu number by about from 34 to 48% comparing with that of base-line-case. The lowest values of drag coefficient ( f) for tube down-stream are obtained at +5° CFDn and -15° CFUp with respect to the base-line case. For tube up-stream, Nu number increases by increasing θ from 0° to -5° and the values of Nu number for θ varying from -5° to -15° have no significant changes. ( f) increases with hw and has negligible effect on ha. Furthermore, optimization analyses of θ and longitudinal fin (LF) are utilized, in four cases, for finding the optimum combination and maximum efficiency. The highest values of heat transfer parameters such as effectiveness (ɛ), area goodness factor (G) and efficiency index (η) and the lowest values of fluid-flow parameters like ( f) and hence the best efficiency, are achieved for -15° CFUp down-stream, ("case 3" of -15° CFUp down-stream and 6 mm LF height) and +5° CFDn down-stream. Correlations of Nu number, ( f) and (ɛ) as a function of θ and Re for the studied cases are performed.

  10. Generation characteristics of photovoltaic power generation equipment at TEPCO R and D center; Gijutsu kaihatsu center taiyoko hatsuden setsubi no hatsuden tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Amano, K; Natori, K [Tokyo Electric Power Co. Inc., Tokyo (Japan)

    1997-11-25

    Solar battery arrays are installed at different tilt angles for actual measurement in an experiment conducted by TEPCO (Tokyo Electric Power Company, Inc.) Research and Development Center for the examination of their power generation characteristics. Arrays of polycrystalline silicon solar battery modules are positioned facing a direction +7 degrees swung from the south on the Center rooftop and verandah, and they are installed at tilt angles of 0, 30, 60, and 90 degrees. An analysis of system characteristics is conducted, and findings mentioned below are obtained. In fiscal 1996, the highest utilization factor of a yearly average of 11.3% is attained with the ones tilted at 30 degrees. As for the utilization factors at the other angles, they are 10.2% at 60 degrees, 8.8% at 0 degrees, and 8.0% at 90 degrees. The integrated design coefficient remains approximately constant irrespective of the different tilt angles of 0, 30, and 60 degrees. The overall design coefficient of the 90 degree-tilted array installed on the verandah is found to be 0.75, which is higher than those exhibited by the others. Appropriate routes of wirings for modules should be worked out to avoid the ill effect of the shadows of steel towers. 2 refs., 11 figs.

  11. Equipment considerations

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    Trace or ultratrace analyses require that the HPLC equipment used, including the detector, be optimal for such determinations. HPLC detectors are discussed at length in Chapter 4; discussion here is limited to the rest of the equipment. In general, commercial equipment is adequate for trace analysis; however, as the authors approach ultratrace analysis, it becomes very important to examine the equipment thoroughly and optimize it, where possible. For this reason they will review the equipment commonly used in HPLC and discuss the optimization steps. Detectability in HPLC is influenced by two factors (1): (a) baseline noise or other interferences that lead to errors in assigning the baseline absorbance; (b) peak width. 87 refs

  12. Online optimal control of variable refrigerant flow and variable air volume combined air conditioning system for energy saving

    International Nuclear Information System (INIS)

    Zhu, Yonghua; Jin, Xinqiao; Du, Zhimin; Fang, Xing

    2015-01-01

    The variable refrigerant flow (VRF) and variable air volume (VAV) combined air conditioning system can solve the problem of the VRF system in outdoor air ventilation while taking advantage of its high part load energy efficiency. Energy performance of the combined air conditioning system can also be optimized by joint control of both the VRF and the VAV parts. A model-based online optimal control strategy for the combined air conditioning system is presented. Simplified adaptive models of major components of the combined air conditioning system are firstly developed for predicting system performances. And a cost function in terms of energy consumption and thermal comfort is constructed. Genetic algorithm is used to search for the optimal control sets. The optimal control strategy is tested and evaluated through two case studies based on the simulation platform. Results show that the optimal strategy can effectively reduce energy consumption of the combined air conditioning system while maintaining acceptable thermal comfort. - Highlights: • A VRF and VAV combined system is proposed. • A model-based online optimal control strategy is proposed for the combined system. • The strategy can reduce energy consumption without sacrificing thermal comfort. • Novel simplified adaptive models are firstly developed for the VRF system

  13. Current Situations and Suggestions for Air--Conditioning Cleaning Industrv in China%空调清洗行业现状分析及发展对策探讨

    Institute of Scientific and Technical Information of China (English)

    白艳中; 郑晨潇

    2012-01-01

    指出了空调运行与管理的不当可能造成室内空气的二次污染,探讨了空调系统可能产生的污染物,借鉴国外成熟空调清洗业的发展经验,分析了我国空调清洗存在的一些问题,针对我国空调清洗业的发展提出了相应的对策。%Air--conditioner has played an increasingly important role in daily life with the improvement of people's living standards. Improper operation and management of air--conditioning system could cause secondary pollution of indoor air. Reference to the mature experience of foreign air--conditoning cleaning industry, this paper analyses the pollutants which may be generated in the air--conditioning system, points out some problems of China's air--conditioning cleaning industry, and finally puts forward some suggests for the development of air--conditioning cleaning industry in China.

  14. IEA SHC Task 38 'Solar air-conditioning and refrigeration'. Danish participation 2007-2010. Appendix; IEA SHC Task 38 'Solar air-conditioning and refrigeration'. Dansk deltagelse 2007-2010. Bilag

    Energy Technology Data Exchange (ETDEWEB)

    Ellehauge, K. (Ellehauge og Kildemoes, Aarhus (Denmark)); Muenster, E. (PlanEnergi, Skoerping (Denmark)); Reinholdt, L. (Teknologisk Institut, Aarhus (Denmark)); Munds, S. (AC-Sun Aps, Horsens (Denmark))

    2011-03-15

    IEA SHC Task 38 'Solar Air-Conditioning and Refrigeration' ran from October 2006 to December 2010. Denmark was represented in the task from January 2007 to December 2010. The aim of the task was to encourage use of solar powered refrigeration and air conditioning systems in particular at residential, commercial and industrial sectors. Furthermore, the aim was to contribute to new research and development activities on new systems and concepts. The appendix contains the publications prepared by the Danish project group.(LN)

  15. IEA SHC Task 38 'Solar air-conditioning and refrigeration'. Danish participation 2007-2010. Appendix; IEA SHC Task 38 'Solar air-conditioning and refrigeration'. Dansk deltagelse 2007-2010. Bilag

    Energy Technology Data Exchange (ETDEWEB)

    Ellehauge, K [Ellehauge og Kildemoes, Aarhus (Denmark); Muenster, E [PlanEnergi, Skoerping (Denmark); Reinholdt, L [Teknologisk Institut, Aarhus (Denmark); Munds, S [AC-Sun Aps, Horsens (Denmark)

    2011-03-15

    IEA SHC Task 38 'Solar Air-Conditioning and Refrigeration' ran from October 2006 to December 2010. Denmark was represented in the task from January 2007 to December 2010. The aim of the task was to encourage use of solar powered refrigeration and air conditioning systems in particular at residential, commercial and industrial sectors. Furthermore, the aim was to contribute to new research and development activities on new systems and concepts. The appendix contains the publications prepared by the Danish project group.(LN)

  16. Application of computational fluid dynamics and pedestrian-behavior simulations to the design of task-ambient air-conditioning systems of a subway station

    Energy Technology Data Exchange (ETDEWEB)

    Fukuyo, Kazuhiro [Graduate School of Innovation and Technology Management, Faculty of Engineering, Yamaguchi University, Tokiwadai 2-16-1, Ube, Yamaguchi 755-8611 (Japan)

    2006-04-15

    The effects of task-ambient (TA) air-conditioning systems on the air-conditioning loads in a subway station and the thermal comfort of passengers were studied using computational fluid dynamics (CFD) and pedestrian-behavior simulations. The pedestrian-behavior model was applied to a standard subway station. Task areas were set up to match with crowdedness as predicted by the pedestrian-behavior simulations. Subsequently, a variety of TA air-conditioning systems were designed to selectively control the microclimate of the task areas. Their effects on the thermal environment in the station in winter were predicted by CFD. The results were compared with those of a conventional air-conditioning system and evaluated in relation to the thermal comfort of subway users and the air-conditioning loads. The comparison showed that TA air-conditioning systems improved thermal comfort and decreased air-conditioning loads. (author)

  17. Acaroid mite allergens from the filters of air-conditioning system in China.

    Science.gov (United States)

    Li, Chao-Pin; Guo, Wei; Zhan, Xiao-Dong; Zhao, Bei-Bei; Diao, Ji-Dong; Li, Na; He, Lian-Ping

    2014-01-01

    Accumulation of acaroid mites in the filters of air-conditioners is harmful to human health. It is important to clarify the allergen components of mites from the filters of local air-conditioning system. The present study was to detect the allergen types in the filters of air-conditioners and assesse their allergenicity by asthmatic models. Sixty aliquots of dust samples were collected from air conditioning filters in civil houses in Wuhu area. Total protein was extracted from the dust samples using PBS and quantified by Bradford method. Allergens I and II were also detected by Western blot using primary antibody (anti-Der f1/2, Der p1/Der f2/Der p2, respectively). Ten aliquots of the positive samples were randomly selected for homogenization and sensitized the mice for developing asthmatic animal models. Total serum IgE level and IFN-γ, IL-4 and IL-5 in the bronchoalveolar lavage fluid (BALF). The allergenicity of the extraction was assessed using pathological sections developed from the mouse pulmonary tissues. The concentration of extract from the 60 samples was ranged from 4.37 μg/ml to 30.76 μg/ml. After analyzing with Western blot, 31 of 60 samples were positive for 4 allergens of acaroid mites, and yet 16 were negative. The levels of total IgE from serum IL-4 and IL-5 from the BALF in the experimental group were apparently higher than that of negative control and PBS group (P 0.05). However,the IFN-γ level in BALF was lower compared with the negative control and PBS group (P 0.05). The pathological changes were evidently emerged in pulmonary tissues, which were similar to those of OVA group, compared with the PBS ground and negative controls. The air-conditioner filters in human dwellings of Wuhu area potentially contain the major group allergen 1 and 2 from D. farinae and D. pteronyssinus, which may be associated with seasonal prevalence of allergic disorders in this area.

  18. Ant-nest corrosion of copper tubing in air-conditioning units

    Directory of Open Access Journals (Sweden)

    Bastidas, D. M.

    2006-10-01

    Full Text Available Ant-nest corrosion is a specific type of premature failure (2-3 months of copper tubes used in air-conditioning units causing the loss of refrigerant liquid and the consequent environment pollution. It is known that attack requires the simultaneous presence of moisture, oxygen and a corrodent, usually an organic acid, such as formic, acetic, propionic or butyric acid or other volatile organic substances like methanol, ethanol, formaldehyde or acetoaldehyde. Approximately 10% of all premature failures of copper tubes used in the heating, ventilation and air-conditioning (HVAC industry are the result of ant-nest corrosion. This type of corrosion usually occurs in thin-wall copper pipes, especially when copper is de-sulphurised, and is known by several names: formicary corrosion, unusual corrosion, branched pits, pinhole corrosion, etc.

    Corrosión por “nido de hormigas” es un tipo específico de fallo prematuro (2-3 meses que tiene lugar en tubos de cobre utilizados en sistemas de aire acondicionado originando la pérdida de líquido refrigerante y la consecuente contaminación ambiental. Es conocido que este tipo de ataque requiere la presencia simultánea de humedad, oxígeno y un medio agresivo, habitualmente un ácido orgánico, como fórmico, acético  propiónico o butírico u otras sustancias orgánicas volátiles tales como metanol, etanol, formaldehido o acetoaldehido. Aproximadamente el 10% de los fallos prematuros en tubos de cobre utilizados en calefacción, ventilación y en la industria de aire acondicionado son el resultado de corrosión por nido de hormigas. Frecuentemente, este tipo de corrosión tiene lugar en tubos de cobre de pared delgada, especialmente cuando el cobre es del tipo desulfurizado, y se conoce con varios nombres: corrosión por ácido fórmico, corrosión no habitual, picaduras ramificadas, corrosión con forma de alfiler, etc.

  19. Health risk air-conditioning system; Insufficient maintenance increases the risk of illness. Gesundheitsrisiko Klimaanlagen; Unzureichende Wartung erhoeht das Erkrankungsrisiko

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1994-01-01

    In Germany every fifth employee who works in air-conditioned rooms complains about headache, an increased proneness to colds and influenza infections as well as allergic reactions. These troubles are often caused by the insufficient maintenance of air-conditioning systems. At present only 15% of the estimated annual demand for maintenance of space hvac-systems is actually carried out. Problematic in case of air-conditioning systems are the so-called air washers used for air humidification which can become an ideal cultur medium for microorganisms. A second problematic area are the often very dirty filters. But health risks can be avoided with regular expert maintenance alone. As first step an analysis of the causes of faults is proposed. (BWI)

  20. [Disinfectants and main sanitary and preventive measures for protection of ventilation and air-conditioning systems from Legionella contamination].

    Science.gov (United States)

    Gerasimov, V N; Golov, E A; Khramov, M V; Diatlov, I A

    2008-01-01

    The study was devoted to selection and assessment of disinfecting preparations for prevention of contamination by Legionella. Using system of criteria for quality assessment of disinfectants, seven newdomestic ones belonging to quaternary ammonium compounds class or to oxygen-containing preparations and designed for disinfecting of air-conditioning and ventilation systems were selected. Antibacterial and disinfecting activities of working solutions of disinfectants were tested in laboratory on the test-surfaces and test-objects of premises' air-conditioning and ventilation systems contaminated with Legionella. High antimicrobial and disinfecting activity of new preparations "Dezactiv-M", "ExtraDez", "Emital-Garant", "Aquasept Plus", "Samarovka", "Freesept", and "Ecobreeze Oxy" during their exposure on objects and materials contaminated with Legionella was shown. Main sanitary and preventive measures for defending of air-conditioning and ventilation systems from contamination by Legionella species were presented.

  1. Actual measurement, hygrothermal response experiment and growth prediction analysis of microbial contamination of central air conditioning system in Dalian, China.

    Science.gov (United States)

    Lv, Yang; Hu, Guangyao; Wang, Chunyang; Yuan, Wenjie; Wei, Shanshan; Gao, Jiaoqi; Wang, Boyuan; Song, Fangchao

    2017-04-03

    The microbial contamination of central air conditioning system is one of the important factors that affect the indoor air quality. Actual measurement and analysis were carried out on microbial contamination in central air conditioning system at a venue in Dalian, China. Illumina miseq method was used and three fungal samples of two units were analysed by high throughput sequencing. Results showed that the predominant fungus in air conditioning unit A and B were Candida spp. and Cladosporium spp., and two fungus were further used in the hygrothermal response experiment. Based on the data of Cladosporium in hygrothermal response experiment, this paper used the logistic equation and the Gompertz equation to fit the growth predictive model of Cladosporium genera in different temperature and relative humidity conditions, and the square root model was fitted based on the two environmental factors. In addition, the models were carried on the analysis to verify the accuracy and feasibility of the established model equation.

  2. A review on the recent development of solar absorption and vapour compression based hybrid air conditioning with low temperature storage

    Directory of Open Access Journals (Sweden)

    Noor D. N.

    2016-01-01

    Full Text Available Conventional air conditioners or vapour compression systems are main contributors to energy consumption in modern buildings. There are common environmental issues emanating from vapour compression system such as greenhouse gas emission and heat wastage. These problems can be reduced by adaptation of solar energy components to vapour compression system. However, intermittence input of daily solar radiation was the main issue of solar energy system. This paper presents the recent studies on hybrid air conditioning system. In addition, the basic vapour compression system and components involved in the solar air conditioning system are discussed. Introduction of low temperature storage can be an interactive solution and improved economically which portray different modes of operating strategies. Yet, very few studies have examined on optimal operating strategies of the hybrid system. Finally, the findings of this review will help suggest optimization of solar absorption and vapour compression based hybrid air conditioning system for future work while considering both economic and environmental factors.

  3. Ten years of sodium cooled steam generator tests on the C.G.V.S. Synthesis of the results obtained on these equipments and operation experiments of an industrial size test facility

    International Nuclear Information System (INIS)

    Fontaine, J.P.; Llory, M.; Quinet, J.L.

    1984-04-01

    From 1970 to 1980, Electricite de France carried out tests on four steam generators of the fast neutron reactor series on an industrial size testing equipment, the C.G.V.S. (large power testing Circuit for Steam Generators heated by Sodium). After a presentation of the testing installation, types of tests carried out and tested apparatus, a balance of lessons drawn from the circuit exploitation, and from the main results obtained on the tested equipments and on the means of calculation COPI and SICLE codes developed or adopted to simulate steam generator operation. 33 figs., 50 refs [fr

  4. Determination of the ejector dimensions of a bus air-conditioning system using analytical and numerical methods

    International Nuclear Information System (INIS)

    Ünal, Şaban

    2015-01-01

    Comfortable journey with commercial buses is an essential goal of transportation companies. An air-conditioning system can play an important role for this comfortable journey but it can put extra load on the engine and extra cost in the fuel consumption. The purpose of this work is to increase the performance of air-conditioning system of the buses by reducing the load on the engine and fuel consumption. Using a two-phase ejector as an expansion valve can increase the coefficient of performance (COP) of the air-conditioning system. An improvement in the COP can reduce the empty vehicle weight and fuel consumption of buses. Two-phase ejector dimensions can be determined using the empirical methods available in the literature. In this paper, the two-phase ejector dimensions of air conditioning system for a bus are calculated using the analytical and numerical methods. First of all, the thermodynamic analysis of the vapor-compression refrigeration cycle with a two-phase ejector is performed, and then the ejector dimensions are subsequently determined. The cooling loads of the midibus and bus with R134a as a refrigerant are assumed to be 14 kW and 32 kW, respectively. The total length of the two-phase ejector for the midibuses and buses due to these cooling loads, are computed to be 480.8 mm and 793.1 mm, respectively. Also, an experimental setup is installed on a midibus air conditioner to turn it into the ejector air conditioning system to validate theoretical results with the experimental study. - Highlights: • Determination of two-phase ejector dimensions of a bus air-conditioning system. • Thermodynamic analysis of the two-phase ejector cooling system. • Experimental study on a midibus air conditioner using two-phase ejector.

  5. Design of automatic control system of temperature in radon chamber controlled by air-condition based on 485 BUS

    International Nuclear Information System (INIS)

    Man Zaigang; Wang Renbo; Zhang Xiongjie; Zhu Zhifu; Tang Bin

    2009-01-01

    Radon chamber can be widely used in various radon measurement instruments for calibration, testing and radon environment experiment. According to requisition, radon chamber temperature should be controllable from +10 degree C to +30 degree C, and the temperature control accuracy of the system reaches ±1 degree C. The design of automatic temperature controlled by air-condition based on 485 BUS is introduced. The software and hardware techniques of how the ATMEL89S52 micro controller controls air-condition and communicates with computer are elaborated on. (authors)

  6. Energy Savings and Economics of Advanced Control Strategies for Packaged Air-Conditioning Units with Gas Heat

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Weimin; Katipamula, Srinivas; Huang, Yunzhi; Brambley, Michael R.

    2011-12-31

    Pacific Northwest National Laboratory (PNNL) with funding from the U.S. Department of Energy's Building Technologies Program (BTP) evaluated a number of control strategies that can be implemented in a controller, to improve the operational efficiency of the packaged air conditioning units. The two primary objectives of this research project are: (1) determine the magnitude of energy savings achievable by retrofitting existing packaged air conditioning units with advanced control strategies not ordinarily used for packaged units and (2) estimating what the installed cost of a replacement control with the desired features should be in various regions of the U.S. This document reports results of the study.

  7. Practical use of CFD for air conditioning duct and defroster designing; Kucho duct defroster no CFD sekkei katsuyo

    Energy Technology Data Exchange (ETDEWEB)

    Okumura, K [Daihatsu Motor Co. Ltd., Osaka (Japan)

    1997-10-01

    The automobile industry have made effort to shorten the development period. Recently CFD (Computational Fluid Dynamics) on initial design stage becomes use for improvement of development efficiency. Although the practical guidepost (computed examples) for air conditioning duct and defroster are a little reported. This report presents how to optimize and standardize the calculational methods, calculational grid, boundary conditions for air conditioning duct and defroster nozzle in the practical use. Also we tried the discontinuous interface grid and the solution adaptive method. 2 refs., 17 figs.

  8. The performance of a mobile air conditioning system with a water cooled condenser

    International Nuclear Information System (INIS)

    Di Battista, Davide; Cipollone, Roberto

    2015-01-01

    Vehicle technological evolution lived, in recent years, a strong acceleration due to the increased awareness of environmental issues related to pollutants and climate altering emissions. This resulted in a series of international regulations on automotive sector which put technical challenges that must consider the engine and the vehicle as a global system, in order to improve the overall efficiency of the system. The air conditioning system of the cabin, for instance, is the one of the most important auxiliaries in a vehicle and requires significant powers. Its performances can be significantly improved if it is integrated within the engine cooling circuit, eventually modified with more temperature levels.In this paper, the Authors present a mathematical model of the A/C system, starting from its single components: compressors, condenser, flush valve and evaporator and a comparison between different refrigerant fluid. In particular, it is introduced the opportunity to have an A/C condenser cooled by a water circuit instead of the external air linked to the vehicle speed, as in the actual traditional configuration. The A/C condenser, in fact, could be housed on a low temperature water circuit, reducing the condensing temperature of the refrigeration cycle with a considerable efficiency increase. (paper)

  9. Air conditioning cool contribution to global warming?; Airconditioning koele bijdrage aan global warming?

    Energy Technology Data Exchange (ETDEWEB)

    Oudshoff, B.

    2010-06-15

    Similar to the Netherlands, the percentage of buildings with air-conditioning is growing steadily in the United Stated (US). This makes it an interesting area for energy saving. New technological developments offer opportunities to drastically reduce energy use for cooling. The best option is obviously to no longer deploy mechanical cooling but this is not a realistic option for warmer areas. This article addresses new technologies and several newly established companies in California and Colorado that target this market. [Dutch] In de Verenigde Staten (VS) groeit het percentage van gebouwen met airconditioning, net als in Nederland, de laatste jaren gestaag door. Hiermee is het een interessant gebied voor mogelijke energiebesparing. Nieuwe technologische ontwikkelingen bieden kansen om het energiegebruik voor koeling drastisch te verminderen. De beste oplossing is uiteraard geen mechanische koeling meer toe te passen maar voor warmere gebieden is die optie niet reeel. In dit artikel wordt ingegaan op nieuwe technologie en enkele startende bedrijven in Californie en Colorado die zich op deze markt richten.

  10. Instability of automotive air conditioning system with a variable displacement compressor. Part 1. Experimental investigation

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Changqing; Dou, Chunpeng; Yang, Xinjiang; Li, Xianting [Department of Building Science, School of Architecture, Tsinghua University, Beijing 100084 (People' s Republic of China)

    2005-11-01

    A test system is built first in order to investigate the instability of the automotive air conditioning (AAC) system with a variable displacement compressor (VDC), and hunting phenomena caused by the large external disturbance in the AAC system with a VDC and a thermal expansion valve, and in the AAC system with a VDC and a fixed-area throttling device are investigated experimentally in part 1 of this paper. The experimental results indicate that there also exist the hunting phenomena in the AAC system with a fixed-area throttling device. The system stability is found to be dependent on the direction of the external disturbance, and the system is apt to cause hunting when the condensing pressure decreases excessively since it may cause two-phase state at the throttling device inlet and make a large disturbance to the system. The piston stroke length will oscillate only when the oscillation amplitudes of forces acting on the wobble plate are great enough, otherwise the piston stroke length will be kept invariable, and then the system instability rule is also suitable for the AAC system with a fixed displacement compressor. From the experimental results, it is concluded that the two-phase flow at the throttling device inlet or at the evaporator outlet is the necessary condition but not sufficient condition for system hunting. Finally, a new concept, conservative stable region, is proposed based on the experimental results and theoretical analysis. (author)

  11. Solar driven air conditioning and refrigeration systems corresponding to various heating source temperatures

    International Nuclear Information System (INIS)

    Wang, R.Z.; Xu, Z.Y.; Pan, Q.W.; Du, S.; Xia, Z.Z.

    2016-01-01

    Highlights: • Modular silica gel–water adsorption chiller was designed and tested. • Single/double effect LiBr–water absorption chiller was operated and tested. • 1.n effect LiBr–water absorption chiller was proposed, designed and tested. • CaCl_2/AC–ammonia adsorption refrigerator was introduced and tested. • NH_3–H_2O absorption ice maker with better internal heat recovery was introduced. - Abstract: Solar driven air conditioning systems can cope with solar collectors working in a wide range of temperatures. Sorption systems, including absorption and adsorption refrigeration systems, are among the best choices for solar cooling. Five systems including modular silica gel–water adsorption chiller, single/double effect LiBr–water absorption chiller, 1.n effect LiBr–water absorption chiller, CaCl_2/AC (activated carbon)–ammonia adsorption refrigerator, and the water–ammonia absorption ice maker with better internal heat recovery were presented. The above five sorption chillers/refrigerators work under various driven temperatures and fulfill different refrigeration demands. The thermodynamic design and system development of the systems were shown. All these systems have improvements in comparison with existing systems and may offer good options for high efficient solar cooling in the near future.

  12. Development of a dynamic model for a DX VAV air conditioning system

    International Nuclear Information System (INIS)

    Chen Wu; Deng Shiming

    2006-01-01

    A direct expansion (DX) variable air volume (VAV) air conditioning (A/C) system consists of a VAV air distribution subsystem and a DX refrigeration plant. This paper reports on the development of a representative and complete dynamic mathematical model for the DX VAV A/C system having a variable speed compressor and pressure independent VAV terminals. The model is component based and takes into account the dynamic behaviors of both the DX refrigeration plant and the VAV air distribution subsystem simultaneously. The dynamic model has been developed based on the principles of mass and energy conservation and using correlations describing the operational performance of some of the system's components, which are either field tested or available from manufacturers. An experimental rig has been set up for the DX VAV A/C system, and experimental work has been conducted to obtain the system's responses to the step change of compressor speed. The dynamic model developed was then validated using the experimental data obtained. Steady state and transient responses for five major operating parameters obtained from both the model and the experiment were compared and found to be in good agreement

  13. Building occupancy diversity and HVAC (heating, ventilation, and air conditioning) system energy efficiency

    International Nuclear Information System (INIS)

    Yang, Zheng; Ghahramani, Ali; Becerik-Gerber, Burcin

    2016-01-01

    Approximately forty percent of total building energy consumption is attributed to HVAC (heating, ventilation, and air conditioning) systems that aim to maintain healthy and comfortable indoor environments. An HVAC system is a network with several subsystems, and there exist heat transfer and balance among the zones of a building, as well as heat gains and losses through a building's envelope. Diverse occupancy (diversity in terms of when and how occupants occupy a building) in spaces could result in increase of loads that are not actual demands for an HVAC system, leading into inefficiencies. This paper introduces a framework to quantitatively evaluate the energy implications of occupancy diversity at the building level, where building information modeling is integrated to provide building geometries, HVAC system layouts, and spatial information as inputs for computing potential energy implications if occupancy diversity were to be eliminated. An agglomerate hierarchical clustering-based iterative evaluation algorithm is designed for iteratively eliminating occupancy diversity. Whole building energy simulations for a real-world building, as well as virtual reference buildings demonstrate that the proposed framework could effectively quantify the HVAC system energy efficiency affected by occupancy diversity and the framework is generalizable to different building geometries, layouts, and occupancy diversities. - Highlights: • Analyze relationships between occupancy diversity and HVAC energy efficiency. • Integrate BIM for quantifying energy implications of occupancy diversity. • Demonstrate the effectiveness and generalizability of iterative evaluation algorithm. • Improve agglomerative hierarchical clustering process using heap data structure.

  14. Remote Supervision and Control of Air Conditioning Systems in Different Modes

    Science.gov (United States)

    Rafeeq, Mohammed; Afzal, Asif; Rajendra, Sree

    2018-01-01

    In the era of automation, most of the application of engineering and science are interrelated with system for optimal operation. To get the efficient result of an operation and desired response, interconnected systems should be controlled by directing, regulating and commanding. Here, air conditioning (AC) system is considered for experimentation, to supervise and control its functioning in both, automated and manual mode. This paper reports the work intended to design and develop an automated and manual AC system working in remote and local mode, to increase the level of comfort, easy operation, reducing human intervention and faults occurring in the system. The Programmable Logical Controller (PLC) and Supervisory Control and Data Acquisition (SCADA) system were used for remote supervision and monitoring of AC systems using series ninety protocol and remote terminal unit modbus protocol as communication module to operate in remote mode. PLC was used as remote terminal for continuous supervision and control of AC system. SCADA software was used as a tool for designing user friendly graphical user interface. The proposed SCADA AC system successfully monitors and controls in accordance within the parameter limits like temperature, pressure, humidity and voltage. With all the features, this designed system is capable of efficient handling of the resources like the compressor, humidifier etc., with all the levels of safety and durability. This system also maintains the temperature and controls the humidity of the remote location and also looks after the health of the compressor.

  15. Experimental studies on improvement of coefficient of performance of window air conditioning unit

    Directory of Open Access Journals (Sweden)

    Tharves Mohideen Sheik Ismail

    2017-01-01

    Full Text Available This paper presents the performance analysis of a window air conditioner unit incorporated with wick less loop heat pipes (WLHP. The WLHP are located on the evaporator side of the air conditioning unit. The working medium for the WLHP is R134a refrigerant gas, an alternate refrigerant. The supply and return humidity of room air, the heat removal rat, and the coefficient of performance of the unit are analyzed for various ambient and room temperatures before and after incorporation of WLHP. The performance curves are drawn by comparing the power consumption and humidity collection rates for various room and ambient temperatures. The results show that coefficient of performance of the unit is improved by 18% to 20% after incorporation of WLHP due to pre-cooling of return air by WLHP, which reduces the thermal load on compressor. Similarly, the energy consumption is reduced by 20% to 25% due to higher thermostat setting and the humidity collection is improved by 35% due to pre-cooling effect of WLHP. The results are tabulated and conclusion drawn is presented based on the performance.

  16. Parametric analysis of a combined dew point evaporative-vapour compression based air conditioning system

    Directory of Open Access Journals (Sweden)

    Shailendra Singh Chauhan

    2016-09-01

    Full Text Available A dew point evaporative-vapour compression based combined air conditioning system for providing good human comfort conditions at a low cost has been proposed in this paper. The proposed system has been parametrically analysed for a wide range of ambient temperatures and specific humidity under some reasonable assumptions. The proposed system has also been compared from the conventional vapour compression air conditioner on the basis of cooling load on the cooling coil working on 100% fresh air assumption. The saving of cooling load on the coil was found to be maximum with a value of 60.93% at 46 °C and 6 g/kg specific humidity, while it was negative for very high humidity of ambient air, which indicates that proposed system is applicable for dry and moderate humid conditions but not for very humid conditions. The system is working well with an average net monthly power saving of 192.31 kW h for hot and dry conditions and 124.38 kW h for hot and moderate humid conditions. Therefore it could be a better alternative for dry and moderate humid climate with a payback period of 7.2 years.

  17. Risk Assessment of Heating, Ventilating, and Air-Conditioning Strategies in Low-Load Homes

    Energy Technology Data Exchange (ETDEWEB)

    Poerschke, Andrew [IBACOS, Inc., Pittsburgh, PA (United States)

    2016-02-17

    "Modern, energy efficient homes conforming to the Zero Energy Ready Home standard face the challenge of meeting high customer expectations for comfort. Traditional heating, ventilation, and air conditioning (HVAC) sizing and control strategies may be insufficient to adequately condition each zone due to unique load patterns in each room caused by a number of factors. These factors include solar heat gains, occupant-related gains, and gains associated with appliances and electronics. Because of shrinking shell loads, these intermittent factors are having an increasingly significant impact on the thermal load in each zone. Consequently, occupant comfort can be compromised. To evaluate the impact of climate and house geometry, as well as HVAC system and control strategies on comfort conditions, IBACOS analyzed the results of 99 TRNSYS multiple-zone simulations. The results of this analysis indicate that for simple-geometry and single-story plans, a single zone and thermostat can adequately condition the entire house. Demanding house geometry and houses with multiple stories require the consideration of multiple thermostats and multiple zones.

  18. Experimental investigation of hydrocarbon mixtures to replace HFC-134a in an automotive air conditioning system

    International Nuclear Information System (INIS)

    Wongwises, Somchai; Kamboon, Amnouy; Orachon, Banchob

    2006-01-01

    This paper presents an experimental study on the application of hydrocarbon mixtures to replace HFC-134a in automotive air conditioners. The hydrocarbons investigated are propane (R290), butane (R600) and isobutane (R600a). The measured data are obtained from an automotive air conditioning test facility utilizing HFC-134a as the refrigerant. The air conditioner, with a capacity of 3.5 kW driven by a Diesel engine, is charged and tested with four different ratios of hydrocarbon mixtures. The experiments are conducted at the same surrounding conditions. The temperature and pressure of the refrigerant at every major position in the refrigerant loop, the temperature, flow rate and humidity of air, torque and engine speed are recorded and analyzed. The parameters investigated are the refrigeration capacity, the compressor power and the coefficient of performance (COP). The results show that propane/butane/isobutane: 50%/40%/10% is the most appropriate alternative refrigerant to replace HFC-134a, having the best performance of all the hydrocarbon mixtures investigated

  19. Experimental study on frosting control of mobile air conditioning system with microchannel evaporator

    International Nuclear Information System (INIS)

    Qu Xiaohua; Shi Junye; Qi Zhaogang; Chen Jiangping

    2011-01-01

    In this paper, a newly developed frost control system is proposed. System bench tests and vehicle test in wind tunnel have been carried out to explore the anti-frosting performance of automotive air conditioning system with microchannel evaporator. The experimental results are compared with the baseline conventional laminated evaporator system. The test results show that the installation position of temperature sensor can dramatically affect the anti-frosting performance. The clutch switching on/off temperature range of the microchannel evaporator is also experimentally studied. The test results show that, with a proper installation position and on/off temperature range, the system COP can be improved, and meanwhile the panel vents' air off temperature can be reduced, and temperature swing can be reduced. - Highlights: → The frost control systems were tested with microchannel and laminated evaporators separately. → The installation position of temperature sensor affects the anti-frosting performance. → Temperature control range affects the anti-frosting performance. → The panel vents' air off temperature and swing can be reduced by proper control parameters. → The system COP can be improved by proper control parameters.

  20. Modelica Library for Building Heating, Ventilation and Air-Conditioning Systems

    Energy Technology Data Exchange (ETDEWEB)

    Wetter, Michael

    2009-06-17

    This paper presents a freely available Modelica library for building heating, ventilation and air conditioning systems. The library is based on the Modelica.Fluid library. It has been developed to support research and development of integrated building energy and control systems. The primary applications are controls design, energy analysis and model-based operation. The library contains dynamic and steady-state component models that are applicable for analyzing fast transients when designing control algorithms and for conducting annual simulations when assessing energy performance. For most models, dimensional analysis is used to compute the performance for operating points that differ from nominal conditions. This allows parameterizing models in the absence of detailed geometrical information which is often impractical to obtain during the conceptual design phase of building systems. In the first part of this paper, the library architecture and the main classes are described. In the second part, an example is presented in which we implemented a model of a hydronic heating system with thermostatic radiator valves and thermal energy storage.

  1. Characterization of biological aerosol exposure risks from automobile air conditioning system.

    Science.gov (United States)

    Li, Jing; Li, Mingzhen; Shen, Fangxia; Zou, Zhuanglei; Yao, Maosheng; Wu, Chang-yu

    2013-09-17

    Although use of automobile air conditioning (AC) was shown to reduce in-vehicle particle levels, the characterization of its microbial aerosol exposure risks is lacking. Here, both AC and engine filter dust samples were collected from 30 automobiles in four different geographical locations in China. Biological contents (bacteria, fungi, and endotoxin) were studied using culturing, high-throughput gene sequence, and Limulus amebocyte lysate (LAL) methods. In-vehicle viable bioaerosol concentrations were directly monitored using an ultraviolet aerodynamic particle sizer (UVAPS) before and after use of AC for 5, 10, and 15 min. Regardless of locations, the vehicle AC filter dusts were found to be laden with high levels of bacteria (up to 26,150 CFU/mg), fungi (up to 1287 CFU/mg), and endotoxin (up to 5527 EU/mg). More than 400 unique bacterial species, including human opportunistic pathogens, were detected in the filter dusts. In addition, allergenic fungal species were also found abundant. Surprisingly, unexpected fluorescent peaks around 2.5 μm were observed during the first 5 min use of AC, which was attributed to the reaerosolization of those filter-borne microbial agents. The information obtained here can assist in minimizing or preventing the respiratory allergy or infection risk from the use of automobile AC system.

  2. Analysis of the Impact of Urban Microclimate on Air Conditioning Load Control

    Directory of Open Access Journals (Sweden)

    Hu Xiaoqing

    2016-01-01

    Full Text Available Due to the presence of urban heat island effect (UHIE, high humidity and other urban microclimate, temperature of city central area rises. This causes that the actual air-conditioning energy consumption (ACEC in the urban central area is much higher than that in the suburbs. Load control of air-conditioners (ACs is considered to be equivalent to a power plant of the same capacity, and it can greatly reduce the system pressure to peak load shift. In this paper, a simplified second order transfer function control model of ACs is presented, and its parameters will be influenced by the ambient temperature and urban microclimate. The temperature is obtained by using the temperature inversion algorithm of the heat island effect. Then, the heat index is calculated by combining temperature and humidity. The ambient temperature index of urban central area is modified based on the above microclimate, and the second order linear time invariant model of aggregated ACs is upgraded to the linear time varying model. Furthermore, the consequent parameter changes of the second order transfer function model are studied and the influence of urban microclimate on AC load control is analyzed. The proposed method is verified on numerical examples

  3. A Closed-Loop Control Strategy for Air Conditioning Loads to Participate in Demand Response

    Directory of Open Access Journals (Sweden)

    Xiaoqing Hu

    2015-08-01

    Full Text Available Thermostatically controlled loads (TCLs, such as air conditioners (ACs, are important demand response resources—they have a certain heat storage capacity. A change in the operating status of an air conditioner in a small range will not noticeably affect the users’ comfort level. Load control of TCLs is considered to be equivalent to a power plant of the same capacity in effect, and it can significantly reduce the system pressure to peak load shift. The thermodynamic model of air conditioning can be used to study the aggregate power of a number of ACs that respond to the step signal of a temperature set point. This paper analyzes the influence of the parameters of each AC in the group to the indoor temperature and the total load, and derives a simplified control model based on the two order linear time invariant transfer function. Then, the stability of the model and designs its Proportional-Integral-Differential (PID controller based on the particle swarm optimization (PSO algorithm is also studied. The case study presented in this paper simulates both scenarios of constant ambient temperature and changing ambient temperature to verify the proposed transfer function model and control strategy can closely track the reference peak load shifting curves. The study also demonstrates minimal changes in the indoor temperature and the users’ comfort level.

  4. Development of salt hydrate eutectics as latent heat storage for air conditioning and cooling

    Energy Technology Data Exchange (ETDEWEB)

    Efimova, Anastasia [Brandenburgische Technische Universität (BTU) Cottbus – Senftenberg, Chair of Inorganic Chemistry, Großenhainer Str. 57, 01968 Senftenberg (Germany); Pinnau, Sebastian; Mischke, Matthias; Breitkopf, Cornelia [Technische Universität Dresden, Chair of Technical Thermodynamics, Helmholtzstr. 14, 01069 Dresden (Germany); Ruck, Michael [Technische Universität Dresden, Chair of Inorganic Chemistry, Bergstr. 66, 01062 Dresden (Germany); Schmidt, Peer, E-mail: peer.schmidt@hs-lausitz.de [Brandenburgische Technische Universität (BTU) Cottbus – Senftenberg, Chair of Inorganic Chemistry, Großenhainer Str. 57, 01968 Senftenberg (Germany)

    2014-01-10

    Graphical abstract: - Highlights: • Inorganic salt hydrates. • Latent heat thermal energy storage. • Thermal behavior of melting and crystallization. • Cycling stability. • Nucleation. - Abstract: Sustainable air conditioning systems require heat reservoirs that operate between 4 and 20 °C. A systematic search for binary and ternary eutectics of inorganic salts and salt hydrates with melting temperatures in this temperature regime and with high enthalpies of fusion has been performed by means of differential scanning calorimetry (DSC). Promising results were obtained for the pseudo-ternary system Zn(NO{sub 3}){sub 2}·6H{sub 2}O, Mn(NO{sub 3}){sub 2}·4H{sub 2}O, and KNO{sub 3} with the melting temperature range 18–21 °C and the enthalpy of fusion of about 110 kJ kg{sup −1}. Suitable nucleating and thickening agents have been found and tested to prevent the mixture from supercooling and phase separation.

  5. Deinococcus multiflagellatus sp. nov., isolated from a car air-conditioning system.

    Science.gov (United States)

    Kim, Dong-Uk; Lee, Hyosun; Lee, Suyeon; Park, Sooyeon; Yoon, Jung-Hoon; Zhao, Lei; Kim, Min-Kyu; Ahn, Jae-Hyung; Ka, Jong-Ok

    2018-04-01

    A gamma radiation-resistant and pink-to-red pigmented bacterial strain, designated ID1504 T , was isolated from a car air-conditioning system sampled in Korea. The cells were observed to be Gram-stain negative, aerobic, motile with peritrichous flagella and short rod-shaped. Phylogenetically, the strain groups with the members of the genus Deinococcus and exhibits high 16S rRNA gene sequence similarities with Deinococcus arenae SA1 T (94.0%), Deinococcus actinosclerus BM2 T (93.9%) and Deinococcus soli N5 T (93.5%). The predominant fatty acids were identified as C 17:0 , C 16:0 , summed feature 3 (C 16:1 ω7c and/or C 16:1 ω6c) and iso-C 17:0 . The major respiratory quinone was identified as MK-8. The polar lipids were found to be comprised of unidentified phospholipids, unidentified glycolipids, an unidentified aminophospholipid and an unidentified lipid. The DNA G+C content of the strain was determined to be 68.3 mol%. On the basis of the phenotypic, genotypic and chemotaxonomic characteristics, strain ID1504 T should be classified in a novel species in the genus Deinococcus, for which the name Deinococcus multiflagellatus sp. nov. (= KACC 19287 T  = NBRC 112888 T ) is proposed.

  6. Modeling and simulation of a solar powered two bed adsorption air conditioning system

    International Nuclear Information System (INIS)

    Li Yong; Sumathy, K.

    2004-01-01

    A simple lumped parameter model is established to investigate the performance of a solar powered adsorption air conditioning system driven by flat-type solar collectors with three different configurations of glazes: (i) single glazed cover; (ii) double glazed cover and (iii) transparent insulation material (TIM) cover. The dynamic performance of a continuous adsorption cycle using a double adsorber along with heat recovery is measured in terms of the temperature histories, gross solar coefficient of performance and specific cooling power. Also, the influences of some important design and operational parameters on the performance of the system are studied. It is found that the chosen three types of collector configurations make no big difference on the performance, but the adsorbent mass and lumped capacitance have significant effects on the system performance as well as on the system size. Simulation results indicate that the effect of overall heat transfer coefficient is not predominant if the cycle duration is longer. Also, there exists an optimum time to initiate the heating of the adsorbent bed in a day's operation

  7. Energy-Saving Benefits of Adiabatic Humidification in the Air Conditioning Systems of Semiconductor Cleanrooms

    Directory of Open Access Journals (Sweden)

    Min-Suk Jo

    2017-11-01

    Full Text Available This paper aimed to evaluate the applicability of adiabatic humidification in the heating, ventilation, and air conditioning (HVAC systems of semiconductor cleanrooms. Accurate temperature and humidity control are essential in semiconductor cleanrooms and high energy consumption steam humidification is commonly used. Therefore, we propose an adiabatic humidification system employing a pressurized water atomizer to reduce the energy consumption. The annual energy consumption of three different HVAC systems were analyzed to evaluate the applicability of adiabatic humidification. The studied cases were as follows: (1 CASE 1: a make-up air unit (MAU with a steam humidifier, a dry cooling coil (DCC, and a fan filter unit (FFU; (2 CASE 2: a MAU with the pressurized water atomizer, a DCC, and a FFU; and (3 CASE 3: a MAU, a DCC, and a FFU, and the pressurized water atomizer installed in the return duct. The energy saving potential of adiabatic humidification over steam humidification has been proved, with savings of 8% and 23% in CASE 2 and CASE 3 compared to CASE 1, respectively. Furthermore, the pressurized water atomizer installed in the return duct exhibits greater energy saving effect than when installed in the MAU.

  8. Incorporating fan control into air-conditioning systems to improve energy efficiency and transient response

    International Nuclear Information System (INIS)

    Yeh, T.-J.; Chen, Yun-Jih; Hwang, Wei-Yang; Lin, Jin-Long

    2009-01-01

    Modern air-conditioners frequently incorporate variable-speed compressors and variable-opening expansion valves with feedback control to improve performance and power efficiency. Because making the fan speeds adjustable adds flexibility to the control design and thus can lead to further improvements in performance and efficiency, this paper proposes two control algorithms, respectively, incorporating the outdoor fan and the indoor fan as the additional control inputs for air-conditioning systems. Both of the control algorithms are designed based on a low-order, linear model obtained from system identification. The first algorithm, which modulates the outdoor fan speed, can reduce the steady state power consumption if the temperature difference between the condenser and the outdoor environment is controlled properly. The second algorithm, which adds one more degree of freedom to control by modulating the indoor fan speed, can improve the transient response because actuator saturations become less likely to occur. The two control algorithms are implemented on a split-type residential air-conditioner and their respective performance is validated experimentally.

  9. Experimental verification of a condenser with liquid–vapor separation in an air conditioning system

    International Nuclear Information System (INIS)

    Chen, Xueqing; Chen, Ying; Deng, Lisheng; Mo, Songping; Zhang, Haiyan

    2013-01-01

    Three liquid–vapor separation condensers (LSC) were tested to evaluate their ability to automatically separate the liquid and vapor during condensation. Each was used in a split-type air conditioner to investigate the performance. The performance of the LSC system having the greatest cooling capacity and energy efficiency ratio (EER) was then compared with that of the system having a baseline fin-and-tube condenser for various ambient temperatures from 29 °C to 43 °C. The results showed that both the cooling capacity and EER of the two systems were almost the same at the three standard conditions in the Chinese standard GB/T 7725-2004, with the LSC having just 67% of the heat transfer area of the baseline condenser. In addition, the LSC system was charged with only 80% of the refrigerant in the baseline system. -- Highlights: ► We tested three liquid–vapor separation condensers in an air conditioning system. ► The best system had the most uniform wall temperature and the smallest pressure drop. ► The LSC system performance with only 67% condenser area was as good as the baseline system. ► LSC system operations are compared for various outdoor temperatures

  10. Experimental evaluation of automotive air-conditioning using HFC-134a and HC-134a

    Science.gov (United States)

    Nasution, Henry; Zainudin, Muhammad Amir; Aziz, Azhar Abdul; Latiff, Zulkarnain Abdul; Perang, Mohd Rozi Mohd; Rahman, Abd Halim Abdul

    2012-06-01

    An experimental study to evaluate the energy consumption of an automotive air conditioning is presented. In this study, these refrigerants will be tested using the experimental rig which simulated the actual cars as a cabin complete with a cooling system component of the actual car that is as the blower, evaporator, condenser, radiators, electric motor, which acts as a vehicle engine, and then the electric motor will operate the compressor using a belt and pulley system, as well as to the alternator will recharge the battery. The compressor working with the fluids HFC-134a and HC-134a and has been tested varying the speed in the range 1000, 1500, 2000 and 2500 rpm. The measurements taken during the one hour experimental periods at 2-minutes interval times for temperature setpoint of 20°C with internal heat loads 0, 500, 700 and 1000 W. The final results of this study show an overall better energy consumption of the HFC-134a compared with the HC-134a.

  11. Energy-Efficient Supermarket Heating, Ventilation, and Air Conditioning in Humid Climates in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Clark, J. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2015-03-01

    Supermarkets are energy-intensive buildings that consume the greatest amount of electricity per square foot of building of any building type in the United States and represent 5% of total U.S. commercial building primary energy use (EIA 2005). Refrigeration and heating, ventilation, and air-conditioning (HVAC) systems are responsible for a large proportion of supermarkets’ total energy use. These two systems sometimes work together and sometimes compete, but the performance of one system always affects the performance of the other. To better understand these challenges and opportunities, the Commercial Buildings team at the National Renewable Energy Laboratory investigated several of the most promising strategies for providing energy-efficient HVAC for supermarkets and quantified the resulting energy use and costs using detailed simulations. This research effort was conducted on behalf of the U.S. Department of Energy (DOE) Commercial Building Partnerships (CBP) (Baechler et al. 2012; Parrish et al. 2013; Antonopoulos et al. 2014; Hirsch et al. 2014). The goal of CBP was to reduce energy use in the commercial building sector by creating, testing, and validating design concepts on the pathway to net zero energy commercial buildings. Several CBP partners owned or operated buildings containing supermarkets and were interested in optimizing the energy efficiency of supermarket HVAC systems in hot-humid climates. These partners included Walmart, Target, Whole Foods Market, SUPERVALU, and the Defense Commissary Agency.

  12. Low-Flow Liquid Desiccant Air-Conditioning: Demonstrated Performance and Cost Implications

    Energy Technology Data Exchange (ETDEWEB)

    Kozubal, E.; Herrmann, L.; Deru, M.; Clark, J.; Lowenstein, A.

    2014-09-01

    Cooling loads must be dramatically reduced when designing net-zero energy buildings or other highly efficient facilities. Advances in this area have focused primarily on reducing a building's sensible cooling loads by improving the envelope, integrating properly sized daylighting systems, adding exterior solar shading devices, and reducing internal heat gains. As sensible loads decrease, however, latent loads remain relatively constant, and thus become a greater fraction of the overall cooling requirement in highly efficient building designs, particularly in humid climates. This shift toward latent cooling is a challenge for heating, ventilation, and air-conditioning (HVAC) systems. Traditional systems typically dehumidify by first overcooling air below the dew-point temperature and then reheating it to an appropriate supply temperature, which requires an excessive amount of energy. Another dehumidification strategy incorporates solid desiccant rotors that remove water from air more efficiently; however, these systems are large and increase fan energy consumption due to the increased airside pressure drop of solid desiccant rotors. A third dehumidification strategy involves high flow liquid desiccant systems. These systems require a high maintenance separator to protect the air distribution system from corrosive desiccant droplet carryover and so are more commonly used in industrial applications and rarely in commercial buildings. Both solid desiccant systems and most high-flow liquid desiccant systems (if not internally cooled) add sensible energy which must later be removed to the air stream during dehumidification, through the release of sensible heat during the sorption process.

  13. Online Air-Conditioning Energy Management under Coalitional Game Framework in Smart Community

    Directory of Open Access Journals (Sweden)

    Wei Fan

    2016-08-01

    Full Text Available Motivated by the potential ability of air conditioning (A/C units in demand response, this paper explores how to utilize A/C units to increase the profit of a smart community. A coalitional game between the households and the load serving entity (LSE in a smart community is studied, where the LSE joins by selling renewable energy to householders and providing an energy saving service to them through an A/C controller. The A/C controller is designed to reduce the amount of electricity purchased from the main grid by controlling A/C units. An online A/C energy management algorithm is developed, based on Lyapunov optimization, that considers both the A/C energy consumption and the thermal comfort level of consumers. In order to quantify the contribution of A/C units, the Shapley value is adopted for distribution of the reward among the participating householders and the LSE, based on their contribution. The simulation result verifies the effectiveness of the proposed coalitional game for a smart community and the algorithm for A/C.

  14. Thermal and economical optimization of air conditioning units with vapor compression refrigeration system

    Energy Technology Data Exchange (ETDEWEB)

    Sanaye, S.; Malekmohammadi, H.R. [Iran University of Science and Technology, Tehran (Iran). Dept. of Mechanical Engineering

    2004-09-01

    A new method of thermal and economical optimum design of air conditioning units with vapor compression refrigeration system, is presented. Such a system includes compressor, condenser, evaporator, centrifugal and axial fans. Evaporator and condenser temperatures, their heating surface areas (frontal surface area and number of tubes), centrifugal and axial fan powers, and compressor power are among the design variables. The data provided by manufacturers for fan (volume flow rate versus pressure drop) and compressor power (using evaporator and condenser temperatures) was used to choose these components directly from available data for consumers. To study the performance of the system under various situations, and implementing the optimization procedure, a simulation program including all thermal and geometrical parameters was developed. The objective function for optimization was the total cost per unit cooling load of the system including capital investment for components as well as the required electricity cost. To find the system design parameters, this objective function was minimized by Lagrange multipliers method. The effects of changing the cooling load on optimal design parameters were studied. (author)

  15. Study of a vapor-compression air-conditioning system for jetliners

    Energy Technology Data Exchange (ETDEWEB)

    Roeyttae, P.

    2009-07-01

    Most modern passenger aeroplanes use air cycle cooling. A high-speed air cycle is a reliable and light option, but not very efficient. This thesis presents research work done to design a novel vapour cooling cycle for aeroplanes. Due to advancements in high-speed permanent magnet motors, the vapour cycle is seen as a competitive option for the air cycle in aeroplanes. The aerospace industry placews tighter demands on the weight, reliability and environmental effects of the machinery than those met by conventional chillers, and thus modifications to conventional design are needed. The thesis is divided into four parts: the initial screening of the working fluid, 1-D design and performance values of the compressor, 1-D off-design value predictions of the compressor and the 3-D design of the compressor. The R24fa was selected as the working fluid based the study. The off-design range of the compressor was predicted to be wide and suitable for the application. The air-conditioning system developed is considerably smaller than previous designs using centrifugal compressors. (orig.)

  16. A dynamic switching strategy for air-conditioning systems operated in light-thermal-load conditions

    International Nuclear Information System (INIS)

    Lin, Jin-Long; Yeh, T.-J.; Hwang, Wei-Yang

    2009-01-01

    Recently, modern air-conditioners have begun to incorporate variable-speed compressors and variable-opening expansion valves, together with feedback control to improve the performance and energy efficiency. However, for the compressor there usually exists a low-speed limit below which its speed can not be continuously modulated unless it is completely turned off. When the air-conditioning system is operated in light-thermal-load conditions, the low-speed limit causes the compressor to run in an on-off manner which can significantly degrade the performance and efficiency. In this paper, a dynamic switching strategy is proposed for such scenarios. The strategy is basically an integration of a cascading control structure, an intuitive switching strategy, and a dynamic compensator. While the control structure provides the nominal performance, the intuitive switching strategy and the dynamic compensator together can account for the compressor's low-speed limitation. Theoretical analysis reveals that when the output matrix of the dynamic compensator is chosen properly, the proposed strategy can effectively reduce the output error caused by the on-off operation of the compressor. Experiments also demonstrate that the proposed strategy can simultaneously provide better regulation for the indoor temperature and improve the energy efficiency at steady state.

  17. The performance of a mobile air conditioning system with a water cooled condenser

    Science.gov (United States)

    Di Battista, Davide; Cipollone, Roberto

    2015-11-01

    Vehicle technological evolution lived, in recent years, a strong acceleration due to the increased awareness of environmental issues related to pollutants and climate altering emissions. This resulted in a series of international regulations on automotive sector which put technical challenges that must consider the engine and the vehicle as a global system, in order to improve the overall efficiency of the system. The air conditioning system of the cabin, for instance, is the one of the most important auxiliaries in a vehicle and requires significant powers. Its performances can be significantly improved if it is integrated within the engine cooling circuit, eventually modified with more temperature levels. In this paper, the Authors present a mathematical model of the A/C system, starting from its single components: compressors, condenser, flush valve and evaporator and a comparison between different refrigerant fluid. In particular, it is introduced the opportunity to have an A/C condenser cooled by a water circuit instead of the external air linked to the vehicle speed, as in the actual traditional configuration. The A/C condenser, in fact, could be housed on a low temperature water circuit, reducing the condensing temperature of the refrigeration cycle with a considerable efficiency increase.

  18. Mode switching control of dual-evaporator air-conditioning systems

    International Nuclear Information System (INIS)

    Lin, J.-L.; Yeh, T.-J.

    2009-01-01

    Modern air-conditioners incorporate variable-speed compressors and variable-opening expansion valves as the actuators for improving cooling performance and energy efficiency. These actuators have to be properly feedback-controlled; otherwise the systems may exhibit even poorer performance than the conventional machines which use fixed-speed compressors and mechanical expansion valves. Particularly for an air-conditioner with multiple evaporators, there are occasions that the machine is operated in a mode that only selected evaporator(s) is(are) turned on, and switching(s) between modes occurs(occur) during the control process. In this case, one needs to have more carefully designed control and switching strategies to ensure the system performance. In this paper, a framework for mode switching control of the dual-evaporator air-conditioning (DEAC) system is proposed. The framework is basically an integration of a controller and a dynamic compensator. The controller, which possesses the flow-distribution capability and assumes both evaporators are on throughout the control process, is intended to provide nominal performance. While mode switching is achieved by varying the reference settings in the controller, the dynamic compensator is used to improve the transient responses immediately after the switching. Experiments indicate that the proposed framework can achieve satisfactory indoor temperature regulation and provide bumpless switching between different modes of operation.

  19. Assessment of productivity loss in air-conditioned buildings using PMV index

    Energy Technology Data Exchange (ETDEWEB)

    Kosonen, R. [Halton OY, Kausala (Finland); Tan, F. [CapitaLand Commercial Limited, Singapore (Singapore)

    2004-07-01

    This theoretical study reports on the assessment of productivity loss in air-conditioned office buildings using the PMV approach and makes use of Wyon's reviews [D.P. Wyon, P.O. Fanger, B.W. Olesen, C.J.K. Pedersen, The mental performance of subjects clothed for comfort at two different air temperatures, Ergonomics 18 (1975) 358-374; D.P. Wyon, Individual microclimate control: required range, probable benefits and current feasibility, in: Proceedings of Indoor Air '96, Institute of Public Health, Tokyo, 1996; D.P. Wyon, Indoor environmental effects on productivity. IAQ 96 Paths to better building environments/Keynote address. Y. Kevin. Atlanta, ASHRAE, pp. 5-15] as the basis to compare and to relate how the productivity loss could be minimised through improved thermal comfort design criteria. The finding shows that task-related performance is significantly correlated with the human perception of thermal environment that in turn is dependent on temperatures. Different combinations of thermal criteria (air velocity, clo, metabolic, etc.) can lead to similar PMV value and the PMV equation is useful to predict productivity loss that is due to the rate of change in thermal conditions. The study also highlights the issues that remain to be resolved in future research. (author)

  20. 40 CFR Appendix D to Subpart B of... - SAE J2810 Standard for Recovery Only Equipment for HFC-134a Refrigerant

    Science.gov (United States)

    2010-07-01

    ... removed from, motor vehicle air-conditioning systems. 1. Scope The purpose of this SAE Standard is to... 700 Standard or allow for recycling of the recovered refrigerant to SAE J2788 specifications by using... (R-134a) Recovery/Recycling Equipment and Recovery/Recycling/Recharging for Mobile Air-Conditioning...