WorldWideScience

Sample records for air conditioning plant

  1. Solar thermal plant of air tube for solar air conditioning; Planta Solar Termica de tubos de vacio para aire acondicionado solar

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, J. C.; Lopez, J.; Coronas, A.

    2004-07-01

    The present implementation of refrigeration and air conditioning technologies driven by thermal solar energy is very limited although there is a great market demand for them for environmental reasons and security of energy supply. In this paper it is presented a detailed technical description of the solar plant installed at the technological Innovation Centre CREVER, and an example of a complete energy analysis of this plant working under the required conditions to be used for solar air conditioning applications. Also it is included a review of solar air conditioning systems state of the art. (Author)

  2. METHODS FOR REPRESENTING THE TUBING OF VENTILATION/AIR-CONDITIONING PLANTS

    Directory of Open Access Journals (Sweden)

    MÂRZA Carmen

    2015-06-01

    Full Text Available The representation of ventilation or air conditioning plants, particularly of the tubing, specifically require the ability to "see into space" or, more completely expressed, to make the connection between the plane and the space. For this reason, in the study program of the "Building Services Engineering" these types of installations have a privileged role. Thus, the students learn the representation in 2D of these plants during the study of the discipline Technical Drawing and further they learn the representation methods in 2D and 3D using the AutoCAD software – respectively the subroutine CAD VENT. Finally, the undergraduates study - as an alternative - the axonometric representation of these plants, by using the Allplan software. The last one offers also elements of the tubes (pipes dimensioning. The paper presents teaching methods using concrete examples.

  3. Heating, ventilating, and air conditioning deactivation thermal analysis of PUREX Plant

    Energy Technology Data Exchange (ETDEWEB)

    Chen, W.W.; Gregonis, R.A. [Westinghouse Hanford Company, Richland, WA (United States)

    1997-08-01

    Thermal analysis was performed for the proposed Plutonium Uranium Extraction Plant exhaust system after deactivation. The purpose of the analysis was to determine if enough condensation will occur to plug or damage the filtration components. A heat transfer and fluid flow analysis was performed to evaluate the thermal characteristics of the underground duct system, the deep-bed glass fiber filter No. 2, and the high-efficiency particulate air filters in the fourth filter building. The analysis is based on extreme variations of air temperature, relative humidity, and dew point temperature using 15 years of Hanford Site weather data as a basis. The results will be used to evaluate the need for the electric heaters proposed for the canyon exhaust to prevent condensation. Results of the analysis indicate that a condition may exist in the underground ductwork where the duct temperature can lead or lag changes in the ambient air temperature. This condition may contribute to condensation on the inside surfaces of the underground exhaust duct. A worst case conservative analysis was performed assuming that all of the water is removed from the moist air over the inside surface of the concrete duct area in the fully developed turbulent boundary layer while the moist air in the free stream will not condense. The total moisture accumulated in 24 hours is negligible. Water puddling would not be expected. The results of the analyses agree with plant operating experiences. The filters were designed to resist high humidity and direct wetting, filter plugging caused by slight condensation in the upstream duct is not a concern. 19 refs., 2 figs.

  4. REACH. Air Conditioning Units.

    Science.gov (United States)

    Garrison, Joe; And Others

    As a part of the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this student manual contains individualized instructional units in the area of air conditioning. The instructional units focus on air conditioning fundamentals, window air conditioning, system and installation, troubleshooting and…

  5. REACH. Air Conditioning Units.

    Science.gov (United States)

    Garrison, Joe; And Others

    As a part of the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this student manual contains individualized instructional units in the area of air conditioning. The instructional units focus on air conditioning fundamentals, window air conditioning, system and installation, troubleshooting and…

  6. Air conditioning and energy conservation. Improved space HVAC systems. Case studies: Office buildings, hotels, shopping centers, skyscrapers, industrial plants

    Energy Technology Data Exchange (ETDEWEB)

    Heiner, H.

    1988-08-01

    Rising energy prices and an increasing demand for comfortable rooms account for the importance attached to the windows and glass used for office buildings, hotels and industrial plants. Both windows and glass have a considerable influence on the thermal behavior and air conditioning of buildings. Among the latest developments are precious metal-coated insulating panes. Selected gases allow to reduce the total thickness of insulating glass and improve noise insulation. The case studies presented refer to the energy-saving air conditioning and space heating, heat recovery and cooling of rooms as well as to the respective control systems. Investigations into the specific energy consumption of building shells reveal the considerable space/tap water heating energy conservation potentials remaining to be utilized.

  7. Air-Conditioning Mechanic.

    Science.gov (United States)

    Marine Corps Inst., Washington, DC.

    This student guide, one of a series of correspondence training courses designed to improve the job performance of members of the Marine Corps, deals with the skills needed by air conditioning mechanics. Addressed in the four chapters, or lessons, of the manual are the following topics: principles of air conditioning, refrigeration components as…

  8. Ecologic air-conditioning. A pilot plant for the geothermal and sorption supported air-conditioning in the HafenCity Hamburg; Oekologische Klimatisierung. Pilotanlage zur geothermisch- und sorptionsgestuetzten Klimatisierung in der HafenCity Hamburg

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Xiaolong; Grabe, Juergen [Technische Univ. Hamburg-Harburg (Germany). Inst. fuer Geotechnik und Baubetrieb

    2011-10-24

    The relatively constant temperatures of the underground at a depth of 100 meters provide the opportunity to air-condition buildings with geothermal energy and economically. Currently, building air conditioning systems in Central Europe exhibit high growth rates. In summer, the task of an air conditioner is to cool and dehumidify air. Especially the dehumidification usually causes a high cooling demand, as the air is cooled below the dew point temperature of 12 C in order to condense out the water. The dew point is well below the demand for a comfortable room temperature of about 19 C. With this in mind, the authors of this contribution report on a principle of alternative dehumidification by means of a so-called sorption wheel. Sorption wheels use the hygroscopic properties of certain substances such as lithium chloride or silica gel in order to dehumidify the air. Thereby, the cooling demand significantly is reduced by the previous dehumidification. The regeneration of the sorption wheel requires heat. This heat can be provided by solar thermal plants and district heating. Since the air can no longer be dehumidified, rich supply temperatures between 16 and 19 C from. These temperatures can be achieved by means of near-surface temperature. Ground registers, geothermal energy probes or geothermal structures such as power poles are used as ground heat exchanger. The authors present the concept and the measurement results of the pilot plant in Hamburg's HafenCity.

  9. Emission Facilities - Air Emission Plants

    Data.gov (United States)

    NSGIC Education | GIS Inventory — Represents the Primary Facility type Air Emission Plant (AEP) point features. Air Emissions Plant is a DEP primary facility type related to the Air Quality Program....

  10. Emission Facilities - Air Emission Plants

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Represents the Primary Facility type Air Emission Plant (AEP) point features. Air Emissions Plant is a DEP primary facility type related to the Air Quality Program....

  11. Assessment of quality and geochemical processes occurring in groundwaters near central air conditioning plant site in Trombay, Maharashtra, India.

    Science.gov (United States)

    Tirumalesh, K; Shivanna, K; Sriraman, A K; Tyagi, A K

    2010-04-01

    This paper summarizes the findings obtained in a monitoring study to understand the sources and processes affecting the quality of shallow and deep groundwater near central air conditioning plant site in Trombay region by making use of physicochemical and biological analyses. All the measured parameters of the groundwaters indicate that the groundwater quality is good and within permissible limits set by (Indian Bureau of Standards 1990). Shallow groundwater is dominantly of Na-HCO(3) type whereas deep groundwater is of Ca-Mg-HCO(3) type. The groundwater chemistry is mainly influenced by dissolution of minerals and base exchange processes. High total dissolved solids in shallow groundwater compared to deeper ones indicate faster circulation of groundwater in deep zone preferably through fissures and fractures whereas groundwater flow is sluggish in shallow zone. The characteristic ionic ratio values and absence of bromide point to the fact that seawater has no influence on groundwater system.

  12. Effects of lighting and air-conditioning systems on growth weight and functional composition of frill-lettuce produced in plant factory

    Science.gov (United States)

    Yoshida, Atsumasa; Okamura, Nobuya; Furukawa, Hajime; Myojin, Chiho; Moriuchi, Koji; Kinoshita, Shinichi

    2017-06-01

    The aim of the present study was to develop optimal air-conditioning systems for plant factories. To verify the effect of particular air-conditioning and lighting systems, cultivation experiments were performed with frill-lettuce for two weeks. In the present study, the relationship between the cultivation condition, the yield (i.e., increase in edible portion weight), and the functional components were discussed. Based on the measured data, increased photosynthetic photon flux density increased antioxidative activity and edible portion weight, possibly because high light intensities are stressful for frill lettuce. Antioxidative activity also increased under conditions of low CO2 concentration, weak and strong winds, and high air temperature because these conditions became stresses for the plants. However, a decrease in edible portion weight was observed under these conditions, implying there is a negative correlation between antioxidative activity and edible portion weight.

  13. Air regenerating and conditioning

    Science.gov (United States)

    Grishayenkov, B. G.

    1975-01-01

    Various physicochemical methods of regenerating and conditioning air for spacecraft are described with emphasis on conditions which affect efficiency of the system. Life support systems used in closed, hermetically sealed environments are discussed with references to actual application in the Soviet Soyuz and Voskhod manned spacecraft. Temperature and humidity control, removal of carbon dioxide, oxygen regeneration, and removal of bacteria and viruses are among the factors considered.

  14. Air conditioning boxes

    Energy Technology Data Exchange (ETDEWEB)

    1981-11-01

    Technical data, layout and function of air conditioning boxes by 6 German producers are described. The boxes cover a volume flow range of 1000 to 100000 m/sup 3//h. All boxes are equipped with heat exchangers, moisturizers, filters, and control elements.

  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. A Novel approach for Low temperature Condenser waste heat Utilization in winter air conditioning for overall Performance Improvement of a Power Plant in Northern India

    Directory of Open Access Journals (Sweden)

    Rajendra Kumar Yadav

    2014-10-01

    Full Text Available The objective of this paper to highlight the scope of utilization of waste heat of condenser for winter air conditioning in and around thermal power stations. The vast amount of low grade condenser waste heat can be used to provide winter air conditioning by utilizing the existing system of year round central air conditioning without additional heavy capital expenditure .The present case study is about North India where peak winter lasts about 90 days . The waste heat utilization for winter conditioning will not only save large amount of electrical energy being used in electrical heaters but also generate additional revenue by selling out extra/spared power ,increase thermal energy utilization ,improve performance of the plant .The novel method of winter air conditioning will also reduce the heat load of the cooling towers, avoid pumping and blow down power as the returning water from air conditioning system can be used as blow down to maintain cooling water parameters in the plant.

  17. Conditional sterility in plants

    Science.gov (United States)

    Meagher, Richard B.; McKinney, Elizabeth; Kim, Tehryung

    2010-02-23

    The present disclosure provides methods, recombinant DNA molecules, recombinant host cells containing the DNA molecules, and transgenic plant cells, plant tissue and plants which contain and express at least one antisense or interference RNA specific for a thiamine biosynthetic coding sequence or a thiamine binding protein or a thiamine-degrading protein, wherein the RNA or thiamine binding protein is expressed under the regulatory control of a transcription regulatory sequence which directs expression in male and/or female reproductive tissue. These transgenic plants are conditionally sterile; i.e., they are fertile only in the presence of exogenous thiamine. Such plants are especially appropriate for use in the seed industry or in the environment, for example, for use in revegetation of contaminated soils or phytoremediation, especially when those transgenic plants also contain and express one or more chimeric genes which confer resistance to contaminants.

  18. Air Conditioning Does Reduce Air Pollution Indoors

    Science.gov (United States)

    Healy, Bud

    1970-01-01

    Report of the winter meeting of the American Society of Heating, Refrigerating and Air-Conditioning Engineers. Subjects covered are--(1) title subject, (2) predictions for the human habitat in 1994, (3) fans, and (4) fire safety in buildings. (JW)

  19. Air Conditioning Does Reduce Air Pollution Indoors

    Science.gov (United States)

    Healy, Bud

    1970-01-01

    Report of the winter meeting of the American Society of Heating, Refrigerating and Air-Conditioning Engineers. Subjects covered are--(1) title subject, (2) predictions for the human habitat in 1994, (3) fans, and (4) fire safety in buildings. (JW)

  20. Effects of mineral nutrition conditions on heat tolerance of chufa (Сyperus esculentus L.) plant communities to super optimal air temperatures in the BTLSS

    Science.gov (United States)

    Shklavtsova, E. S.; Ushakova, S. A.; Shikhov, V. N.; Anishchenko, O. V.

    2014-09-01

    The use of mineralized human wastes as a basis for nutrient solutions will increase the degree of material closure of bio-technical human life support systems. As stress tolerance of plants is determined, among other factors, by the conditions under which they have been grown before exposure to a stressor, the purpose of the study is to investigate the level of tolerance of chufa (Cyperus esculentus L.) plant communities grown in solutions based on mineralized human wastes to a damaging air temperature, 45 °C. Experiments were performed with 30-day-old chufa plant communities grown hydroponically, on expanded clay aggregate, under artificial light, at 690 μmol m-2 s-1 PAR and at a temperature of 25 °C. Plants were grown in Knop’s solution and solutions based on human wastes mineralized according to Yu.A. Kudenko’s method, which contained nitrogen either as ammonium and urea or as nitrates. The heat shock treatment lasted 20 h at 690 and 1150 μmol m-2 s-1 PAR. Chufa heat tolerance was evaluated based on parameters of CO2 gas exchange, the state of its photosynthetic apparatus (PSA), and intensity of peroxidation of leaf lipids. Chufa plants grown in the solutions based on mineralized human wastes that contained ammonium and urea had lower heat tolerance than plants grown in standard mineral solutions. Heat tolerance of the plants grown in the solutions based on mineralized human wastes that mainly contained nitrate nitrogen was insignificantly different from the heat tolerance of the plants grown in standard mineral solutions. A PAR intensity increase from 690 μmol m-2 s-1 to 1150 μmol m-2 s-1 enhanced heat tolerance of chufa plant communities, irrespective of the conditions of mineral nutrition under which they had been grown.

  1. Air Conditioning Overflow Sensor

    Science.gov (United States)

    1996-01-01

    The Technology Transfer Office at Stennis Space Center helped a local inventor develop a prototype of an attachment for central air conditioners and heat pumps that helps monitor water levels to prevent condensation overflow. The sensor will indicate a need for drain line maintenance and prevent possible damage caused by drain pan water spillover. An engineer in the Stennis Space Center prototype Development Laboratory used SSC sensor technology in the development of the sensor.

  2. Air Conditioning Overflow Sensor

    Science.gov (United States)

    1996-01-01

    The Technology Transfer Office at Stennis Space Center helped a local inventor develop a prototype of an attachment for central air conditioners and heat pumps that helps monitor water levels to prevent condensation overflow. The sensor will indicate a need for drain line maintenance and prevent possible damage caused by drain pan water spillover. An engineer in the Stennis Space Center prototype Development Laboratory used SSC sensor technology in the development of the sensor.

  3. SOLAR AIR CONDITIONING OF BUILDING

    Directory of Open Access Journals (Sweden)

    Debrayan Bravo Hidalgo

    2015-04-01

    Full Text Available Air Conditioning with renewable energy is a key issue in the region's energy policy. The high temperatures usually attributed to climate change and the increase of the standard of living in society continues increasing energy demand in order to establish the conditions for thermal comfort in buildings. Solar air conditioning, although it contains a mature technology, its level of market introduction and acceptance by designers of buildings is exhaustive. This paper discusses the feasibility of these projects, identifies non-technological type barriers that hinders such use and implementation of solar energy for air conditioning systems, and finally, it approaches some criteria and recommendations to overcome these obstacles.

  4. Plant response to polluted air

    Energy Technology Data Exchange (ETDEWEB)

    Kendrick, J.B. Jr.; Darley, E.F.; Middleton, J.T.; Paulus, A.O.

    1956-08-01

    Field observations and controlled fumigation experiments have shown that plants differ in their response to atmospheric contamination by ethylene, herbicides, fluorides, sulfur dioxide, and smog, or oxidized hydrocarbons. Controlled experiments have also shown that plant response to air pollution varies with species and variety of plant, age of plant tissue, soil fertility levels, soil moisture, air temperatures during the prefumigation growth period, and presence of certain agricultural chemicals on leaves. The leaves of many plants; such as tomato, African marigold, fuchsia, pepper, and potato, become curved and malformed in the presence of ethylene, while those of cantaloupe, China aster, gardenia, Cattleya orchid, and snapdragon do not. Ethylene may cause serious damage to the sepals of orchids without injury to the petals or leaves.

  5. 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...

  6. Changes in catalase activity in leaves of woody and bushy plants in the conditions of air pollution by compounds of fluorine, sulfur and nitrogen

    Directory of Open Access Journals (Sweden)

    Y. Prysedskyj

    2016-08-01

    Full Text Available Recently environmental pollution by industrial waste products has become a significant environmental factor that essentially limits the vital functions of plants and reduces their species diversity. The antioxidant system is of special importance for tolerance reactions of plants to stressful environmental conditions, in particular, contamination by industrial pollutants. One of the constituents of this system is oxidoreductase, including catalase. Consequently, we have conducted experiments to determine how the nature of the complex compounds of fluorine, nitrogen and sulfur influences catalase activity in leaves of selected species of trees and shrubs. The investigation was made according to the complete factorial experiment that allowed us to study the effect of these pollutants both individually and in combination. We used the iodometric method to determine the level of catalase activity. Statistical analysis of the obtained results was performed by means of dispersion analysis with the comparison according to the Duncan method. The results of the research showed the possible impact of pollutants on the activity of catalase, which depends on the resilience of the plants, structure and duration of potency of the pollutants. With less resilient plant species (Sorbus aucuparia L., Fraxinus lanceolata Borkh. air pollution with a combination of fluorine, sulfur and nitrogen in most cases caused a reduction of catalase activity. Thus, in S. aucuparia a 5-hour exposure to low concentrations of pollutants (HF – 0.2 ml/m3, NH3 – 1.2 ml/m3, SO2 and H2SO4 – 0.9–1.0 ml/m3 caused an inhibition of catalase activity by 40.5%, and a ten-hour exposure caused a 61.4% inhibition compared with the control plants. With increased concentrations of pollutants  catalase function was inhibited by 35.8–73.6%, depending on the duration of their fumigation. For F. lanceolata, the pollutants’ effect on catalase activity caused a decrease in function of this

  7. Low Energy Air Conditioning for Hot Climates

    OpenAIRE

    Almutairi, Hamad Hhn

    2012-01-01

    Fossil fuels are the major sources of electrical power generation in the world. Among all fossil fuels, oil is considered as the most sought-after fuel. The burden on countries that provide subsidized electricity produced from oil-fired power plants is noteworthy. Kuwait is a notable example of these countries. Electricity in Kuwait is heavily consumed by residential air conditioning, which comprises 60% of the total electricity generated at peak times on a hot summer day. From this perspecti...

  8. Indoor plants as air cleaners

    DEFF Research Database (Denmark)

    Dela Cruz, Majbrit; Christensen, Jan H.; Müller, Renate

    2015-01-01

    Plants have been used decoratively indoors for centuries. For the last 25-30 years, their beneficial abilities to reduce the levels of harmful volatile organic compounds (VOCs) from the indoor air have also been investigated. Previous studies have shown that VOCs are removed by the plant itself......, but also by microorganisms in the soil. Furthermore, the rate of removal is dependent on the plant species and can be influenced by exogenous factors such as light intensity and VOC concentration. The research within this field is, however, limited by the fact that the knowledge gained from laboratory...... be an underestimation of the plants' real potential. The next step will be to use the new system to investigate the effects of the exogenous factors temperature, light intensity and CO2 concentration on VOC removal rates....

  9. 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.

  10. High Energy Efficiency Air Conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Edward McCullough; Patrick Dhooge; Jonathan Nimitz

    2003-12-31

    This project determined the performance of a new high efficiency refrigerant, Ikon B, in a residential air conditioner designed to use R-22. The refrigerant R-22, used in residential and small commercial air conditioners, is being phased out of production in developed countries beginning this year because of concerns regarding its ozone depletion potential. Although a replacement refrigerant, R-410A, is available, it operates at much higher pressure than R-22 and requires new equipment. R-22 air conditioners will continue to be in use for many years to come. Air conditioning is a large part of expensive summer peak power use in many parts of the U.S. Previous testing and computer simulations of Ikon B indicated that it would have 20 - 25% higher coefficient of performance (COP, the amount of cooling obtained per energy used) than R-22 in an air-cooled air conditioner. In this project, a typical new R-22 residential air conditioner was obtained, installed in a large environmental chamber, instrumented, and run both with its original charge of R-22 and then with Ikon B. In the environmental chamber, controlled temperature and humidity could be maintained to obtain repeatable and comparable energy use results. Tests with Ikon B included runs with and without a power controller, and an extended run for several months with subsequent analyses to check compatibility of Ikon B with the air conditioner materials and lubricant. Baseline energy use of the air conditioner with its original R-22 charge was measured at 90 deg F and 100 deg F. After changeover to Ikon B and a larger expansion orifice, energy use was measured at 90 deg F and 100 deg F. Ikon B proved to have about 19% higher COP at 90 deg F and about 26% higher COP at 100 deg F versus R-22. Ikon B had about 20% lower cooling capacity at 90 deg F and about 17% lower cooling capacity at 100 deg F versus R-22 in this system. All results over multiple runs were within 1% relative standard deviation (RSD). All of these

  11. Improving efficiency of existing air-conditioning

    Science.gov (United States)

    Obler, H. D.

    1977-01-01

    Inexpensive duct work changes improves hot-and-cold deck air conditioning units. Energy cost of reheating cooled air can be eliminated by tying all cold air decks to one air-conditioning unit and all hot decks to another. Resultant energy savings are easily possible with two or more units.

  12. Distribution of small dispersive coal dust particles and absorbed radioactive chemical elements in conditions of forced acoustic resonance in iodine air filter at nuclear power plant

    CERN Document Server

    Ledenyov, Oleg P

    2013-01-01

    The physical features of distribution of the small dispersive coal dust particles and the adsorbed radioactive chemical elements and their isotopes in the absorber with the granular filtering medium with the cylindrical coal granules were researched in the case of the intensive air dust aerosol stream flow through the iodine air filter (IAF). It was shown that, at the certain aerodynamic conditions in the IAF, the generation of the acoustic oscillations is possible. It was found that the acoustic oscillations generation results in an appearance of the standing acoustic waves of the air pressure (density) in the IAF. In the case of the intensive blow of the air dust aerosol, it was demonstrated that the standing acoustic waves have some strong influences on both: 1) the dynamics of small dispersive coal dust particles movement and their accumulation in the IAF; 2) the oversaturation of the cylindrical coal granules by the adsorbed radioactive chemical elements and their isotopes in the regions, where the antin...

  13. Air Conditioning Systems from a 2nd Law Perspective

    Directory of Open Access Journals (Sweden)

    Luigi Marletta

    2010-04-01

    Full Text Available In this paper exergy analysis is used to assess the performance of the three most common air conditioning plant schemes: all-air, dual-duct and fan-coil systems. The results are presented in terms of flow diagrams to provide a clear picture of the exergy flow across the systems. The most relevant outcomes are that the air cooling and dehumidification is the process most responsible for the exergy loss and that the exergy efficiency of the overall systems is rather low; thus the quest for more appropriate technologies. Solar-assisted air-conditioning is also discussed, outlining the possibilities and the constraints.

  14. 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.

  15. Concentrated Solar Air Conditioning for Buildings Project

    Science.gov (United States)

    McLaughlin, Rusty

    2010-01-01

    This slide presentation reviews project to implement the use of solar power to provide air conditioning for NASA buildings. Included is an overall conceptual schematic, and an diagram of the plumbing and instrumentation for the project. The use of solar power to power air conditioning in buildings, particularly in the Southwest, could save a significant amount of money. DOD studies have concluded that air conditioning accounts for 30-60% of total energy expenditures.

  16. Low energy air conditioning of shelters for telecommunication networks

    Energy Technology Data Exchange (ETDEWEB)

    Romagnoni, P. [Ist. Univ. di Architettura, Venezia (Italy); Scattolin, M. [Liebert Hiross, Piove di Sacco (PD) (Italy); Zecchin, R. [Dipt. di Fisica Tecnica, Padova (Italy)

    2000-07-01

    The control of the air temperature in a shelter for telecommunication networks is an important task for the correct operation of its electronic equipment. Different technical solutions have been studied in order to improve the energy performances of air conditioning plants: for this purpose direct free cooling allows to reduce the energy consumption to maintain the internal air temperature below the prescribed values. Nowadays the internal air temperature may rise up to 60 C, due to the high technology of the electronic equipment, and new solutions for the air temperature control can be proposed. This paper analyses the dynamic thermal performances of a shelter used in telecommunication networks, fitted up with an ''air - to air'' plate heat exchanger without mixing between internal and external air flows. Useful information, concerning the thermal and energy performances of this system is given for design purposes. (orig.)

  17. 火力发电厂水源热泵空调系统与传统空调系统的技术经济性比较%Technical and Economic Comparison between Water-Source Heat Pump Air-Conditioning System and Classical Air-Conditioning System in Fossil Fuel Power Plants

    Institute of Scientific and Technical Information of China (English)

    王明国; 毛永东; 卢柏春; 谢网度

    2013-01-01

    Water-source heat pump air-conditioning as an energy-efficient, environmentally friendly air-conditioning system is gained more attention, and has a broad development prospects. According to Huarun Lianyuan power plant project, this paper has discussed the advantages about water-source heat pump air-conditioning system through the theoretical and economic comparison. The Water source heat pump air-conditioning system has a broad application value.%  水源热泵空调作为一种高效节能,环保型的空调系统正日益受到人们的重视,有着广阔的发展前景。介绍了华润电力涟源坑口电厂工程,通过与传统空调系统的技术经济比较论述其优越性,具有推广应用的价值。

  18. No-reheat air-conditioning

    Science.gov (United States)

    Obler, H. D.

    1980-01-01

    Air conditioning system, for environmentally controlled areas containing sensitive equipment, regulates temperature and humidity without wasteful and costly reheating. System blends outside air with return air as dictated by various sensors to ensure required humidity in cooled spaces (such as computer room).

  19. 火力发电厂采暖空调系统余热利用优化设计%The Optimum Design of the Waste Heat Utilization of Heating&Air-conditioning System in Thermal Power Plant

    Institute of Scientific and Technical Information of China (English)

    费洪磊; 刘欢; 薛岑

    2015-01-01

    我国能源紧缺,一次能源及各种余热资源利用水平较低,深度挖掘利用电厂余热,制定合理的回收利用方案,优化设计采暖空调系统,提高电厂余热利用率十分重要. 基于电厂采暖空调系统余热利用存在的问题,详细介绍了火力发电厂采暖空调系统余热利用的优化设计.%Because of the energy shortage and a lower utilization level of primary energy and various waste heat resources utilization in China, the deep excavation and utilization of the waste heat in thermal power plant, the formulation of reasonable recycling scheme, the optimum design of heating & air-conditioning system and the improvement of utilization rate of waste heat are very important.Based on the problems existing in the waste heat utilization of heating&air-conditioning system in thermal power plant, this paper introduces in detail the optimum design of the waste heat utilization of heating&air-conditioning system in thermal power plant.

  20. Protection of plants against air pollutants: Role of chemical protectants

    Energy Technology Data Exchange (ETDEWEB)

    Pandey, J.; Agrawal, M. (Banaras Hindu Univ., Varanasi (India))

    1993-03-01

    The protection of plants against air pollution damage can best be achieved either by developing pollution-tolerant cultivars or by using chemical protectants. Use of chemical protectants such as pesticides, growth regulators, anti-oxidants, fertilizers, etc. is a short-term solution to reduce the risk of air pollution damage. In addition, these protectants help in understanding the mechanism of air pollution toxicity and provide a scientific basis for assessing crop losses in field conditions. 95 refs.

  1. Air Conditioning. Performance Objectives. Intermediate Course.

    Science.gov (United States)

    Long, William

    Several intermediate performance objectives and corresponding criterion measures are listed for each of seven terminal objectives for an intermediate air conditioning course. The titles of the seven terminal objectives are Refrigeration Cycle, Job Requirement Skills, Air Conditioning, Trouble Shooting, Performance Test, Shop Management, and S.I.E.…

  2. HEATING AND AIR CONDITIONING EDUCATIONAL PROGRAM.

    Science.gov (United States)

    Lennox Industries, Inc., Marshalltown, IA.

    INCREASED MOTIVATION, INCREASED INITIAL COMPREHENSION, AND INCREASED RETENTION ARE THE PRIME GOALS OF THE LENNOX HEATING AND AIR CONDITIONING EDUCATION PROGRAM. IT IS A COMPLETE PROGRAM WITH ALL THE TEACHING TOOLS REQUIRED TO PRODUCE A KNOWLEDGEABLE HEATING AND AIR-CONDITIONING INSTALLER OR SERVICE MAN. THIS INSTRUCTIONAL PROGRAM IS DESIGNED…

  3. Air Conditioning and Heating Technology--II.

    Science.gov (United States)

    Gattone, Felix

    Twenty-eight chapters and numerous drawings provide information for instructors and students of air conditioning and heating technology. Chapter 1 lists the occupational opportunities in the field. Chapter 2 covers the background or development of the industry of air conditioning and heating technology. Chapter 3 includes some of the principle…

  4. Air Conditioning. FOS: Fundamentals of Service.

    Science.gov (United States)

    Employment and Training Administration (DOL), Washington, DC. Office of Youth Programs.

    This manual on air conditioning is one of a series of power mechanics texts and visual aids covering theory of operation, diagnosis, and repair. Information is presented for use by vocational students and teachers as well as shop servicemen and laymen. Focus is on air conditioning systems for mobile machines, but most of the information also…

  5. Air Conditioning. Performance Objectives. Intermediate Course.

    Science.gov (United States)

    Long, William

    Several intermediate performance objectives and corresponding criterion measures are listed for each of seven terminal objectives for an intermediate air conditioning course. The titles of the seven terminal objectives are Refrigeration Cycle, Job Requirement Skills, Air Conditioning, Trouble Shooting, Performance Test, Shop Management, and S.I.E.…

  6. Air Conditioning and Heating Technology--II.

    Science.gov (United States)

    Gattone, Felix

    Twenty-eight chapters and numerous drawings provide information for instructors and students of air conditioning and heating technology. Chapter 1 lists the occupational opportunities in the field. Chapter 2 covers the background or development of the industry of air conditioning and heating technology. Chapter 3 includes some of the principle…

  7. A novel summer air conditioning system

    Energy Technology Data Exchange (ETDEWEB)

    Al-Nimr, M.A.; Abu Nabah, B.A.; Naji, M. [Jordan Univ. of Science and Technology, Irbid (Jordan). Dept. of Mechanical Engineering

    2002-09-01

    A novel summer air conditioning system is proposed. The proposed system modifies the work of the classical evaporative summer air conditioning system. The performance of the proposed system is investigated quantitatively, and a comparison between the performance of the classical and the modified systems is conducted. It is found that the modified system improves the performance of the classical one by about 100%. (author)

  8. Recent air conditioning systems of shopping buildings

    Energy Technology Data Exchange (ETDEWEB)

    Nagashima, Hironori

    1988-11-05

    In the air conditioning system in the shopping building, both the distributed air conditioning and DDC control methods have been increasingly adopted. The distributed air conditioning method, with a microcomputer mounted thereon, has attained the level sufficiently corresponding to the large scale building. While, the DDC control method, like the distributed air conditioning method, is considerably effective on the system having many surveillance control items. To engineer the energy conservation of air conditioning system in the shopping building, the utilization of atmospheric air as natural energy and control method for the ambient room condition reexamined must be studied. For the former, the atmospheric air intake quantity control to dilute CO and CO/sub 2/, and atmospheric air purge system prior to the air cooling are useful. While for the latter, the control method aiming at the comfort range, so called zero energy band control method is recommendable. Further for the temperature and humidity control, the DDC control by local controller is useful. 6 figures, 1 table.

  9. 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.

  10. 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 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.

  11. Carbon Emissions from air-Conditioning

    OpenAIRE

    Rajesh Kumar

    2013-01-01

    This paper explores electricity consumption and carbon emissions associated with air-conditioning. The total heat load of a room fitted with air conditioner of 1.5 ton capacity has been calculated by calculating conduction and ventilation losses. Solar heat gain and internal gain were taken as the other two parameters for the total heat calculation.

  12. Carbon Emissions from air-Conditioning

    Directory of Open Access Journals (Sweden)

    Rajesh Kumar

    2013-01-01

    Full Text Available This paper explores electricity consumption and carbon emissions associated with air-conditioning. The total heat load of a room fitted with air conditioner of 1.5 ton capacity has been calculated by calculating conduction and ventilation losses. Solar heat gain and internal gain were taken as the other two parameters for the total heat calculation.

  13. 固体吸附式空调/热泵在火电厂中的应用研究%STUDY ON APPLYING SOLID-ADSORPTION AIR CONDITIONING / HEAT PUMP IN THERMAL POWER PLANT

    Institute of Scientific and Technical Information of China (English)

    李中华; 王如竹; 刘建军; 柳正军; 刘洪文

    2001-01-01

    采用新型固体吸附式制冷技术开发了电站锅炉排污热回收系统。该系统可直接回收排污热进行空调制冷,并对电厂热力系统进行热泵供热,不但节约大量空调用电,而且提高了机组热经济性,具有显著的节能效果。%A heat recovery system of discharged waste water from boilers in thermal power plant was developed. The recovered heat can be used to drive solid-adsorption refrigerator for air conditioning and supply heat to heat-pump for thermal system, reducing greatly the electricity consumption of air conditioning, improving thermal efficiency of generating units, resulting in obvious energy-saving effect.

  14. Effects of air pollution on plants

    Energy Technology Data Exchange (ETDEWEB)

    Seidman, G.

    1965-01-01

    Weather, automobile exhaust, waste dumps and industrial activities are major factors in the creation of air pollution problems. The first indication of an air pollution problem is often the injury that appears on comparatively sensitive vegetation. Sulfur dioxide causes both acute and chronic plant injury. Plants especially sensitive to SO/sub 2/ are alfalfa, cosmos, sweet pea, bachelor's button, and blackberry. Fluoride causes characteristic injury on plants. Plants sensitive to fluoride injury are gladiolus, azalea, tulip, and young needles of pine. Ethylene damage to plants was initially noted in greenhouses using artificial gas for heating. Orchids and carnations are sensitive to ethylene. Ozone is highly reactive and causes typical spotting injury to the upper surface of leaves. PAN causes injury to vegetation, especially petunia and lettuce. Other pollutants also cause plant injury. Mercury vapor, chlorine gas, ammonia, H/sub 2/S, CO, and nitrogen oxides are minor hazards. Susceptibility of vegetation to air pollution depends on various things such as variety of plants, amount of moisture available to the plants, temperature, and amount of sunlight during the period of air pollution. 8 references.

  15. Biomonitoring of air quality using plants

    Energy Technology Data Exchange (ETDEWEB)

    Mulgrew, A.; Williams, P. [King' s Coll., London (United Kingdom). Monitoring and Assessment Research Centre - WHO Collaborating Centre for Monitoring and Assessment

    2000-02-01

    This report is an update of the MARC Report No. 32 'Biological Monitoring' and a first volume referring to a WHO project on biological monitoring. The monograph reviews comprehensively the existing literature on biological monitoring of air quality with plants. This review includes consideration of all plant species that are currently, or have a potential of, being used as bioindicators of air pollution. This review is intended to serve as a background paper for the derivation of guidelines for the use of biological monitors in air pollution control. (orig.)

  16. Plants Clean Air and Water for Indoor Environments

    Science.gov (United States)

    2007-01-01

    Wolverton Environmental Services Inc., founded by longtime government environmental scientist B.C. "Bill" Wolverton, is an environmental consulting firm that gives customers access to the results of his decades of cutting-edge bioremediation research. Findings about how to use plants to improve indoor air quality have been published in dozens of NASA technical papers and in the book, "How to Grow Fresh Air: 50 Houseplants That Purify Your Home or Office." The book has now been translated into 12 languages and has been on the shelves of bookstores for nearly 10 years. A companion book, "Growing Clean Water: Nature's Solution to Water Pollution," explains how plants can clean waste water. Other discoveries include that the more air that is allowed to circulate through the roots of the plants, the more effective they are at cleaning polluted air; and that plants play a psychological role in welfare in that people recover from illness faster in the presence of plants. Wolverton Environmental is also working in partnership with Syracuse University, to engineer systems consisting of modular wicking filters tied into duct work and water supplies, essentially tying plant-based filters into heating, ventilation, and air conditioning (HVAC) systems. Also, the company has recently begun to assess the ability of the EcoPlanter to remove formaldehyde from interior environments. Wolverton Environmental is also in talks with designers of the new Stennis Visitor's Center, who are interested in using its designs for indoor air-quality filters

  17. Air conditioning for data processing system areas

    Directory of Open Access Journals (Sweden)

    Hernando Camacho García

    2011-06-01

    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.

  18. Detection of air pollutant effects by means of bioindicators. [Plants

    Energy Technology Data Exchange (ETDEWEB)

    Rabe, R.

    Two procedures of bioindication of air pollution are in practice: the 'passive monitoring' and the 'active monitoring'. In the case of passive monitoring in natural vegetation plant association alterations are assessed, or in single plants (also in cultivated plants) visible or subtle injuries are appraised (reaction indicators); the estimation of pollutant accumulation in plant material is done with accummulation indicators. For the 'active monitoring' mostly the same methods are used as in the passive monitoring - but test plants are exposed to air pollution under highly standardized conditions. Bioindicators allow in some way to recognize level and type of air pollution, its dissemination in space and time and its effects on parts of the burdened ecosystems. Complex air pollution types are indicated by plants susceptible generally to pollution and not to specific pollutants as in some manner lichens. These plants are used in landscape and urban planning processes regarding air quality demands. In this paper several procedures and the applicability of bioindication are presented.

  19. Reduced bleed air extraction for DC-10 cabin air conditioning

    Science.gov (United States)

    Newman, W. H.; Viele, M. R.; Hrach, F. J.

    1980-01-01

    It is noted that a significant fuel savings can be achieved by reducing bleed air used for cabin air conditioning. Air in the cabin can be recirculated to maintain comfortable ventilation rates but the quality of the air tends to decrease due to entrainment of smoke and odors. Attention is given to a development system designed and fabricated under the NASA Engine Component Improvement Program to define the recirculation limit for the DC-10. It is shown that with the system, a wide range of bleed air reductions and recirculation rates is possible. A goal of 0.8% fuel savings has been achieved which results from a 50% reduction in bleed extraction from the engine.

  20. Heating, ventilation and air conditioning system modelling

    Energy Technology Data Exchange (ETDEWEB)

    Whalley, R.; Abdul-Ameer, A. [British University in Dubai (United Arab Emirates)

    2011-03-15

    Heating, ventilation and air conditioning modelling methods, for large scale, spatially dispersed systems are considered. Existing techniques are discussed and proposals for the application of novel analysis approaches are outlined. The use of distributed-lumped parameter procedures enabling the incorporation of the relatively concentrated and significantly dispersed, system element characteristics, is advocated. A dynamic model for a heating, ventilation and air conditioning system comprising inlet and exhaust fans, with air recirculation, heating/cooling and filtration units is presented. Pressure, airflow and temperature predictions within the system are computed following input, disturbance changes and purging operations. The generalised modelling advancements adopted and the applicability of the model for heating, ventilation and air conditioning system simulation, re-configuration and diagnostics is emphasised. The employment of the model for automatic, multivariable controller design purposes is commented upon. (author)

  1. [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.

  2. Air conditioning. Special issue; Luchtbehandeling. Themanummer

    Energy Technology Data Exchange (ETDEWEB)

    Montague, M.; Liew, R.; Daruwalla, H.; Wenzek, J. [AAF International, Amsterdam (Netherlands); De Lede, F. [Klimaatinstallaties Kats en Waalwijk, Gorinchem (Netherlands); Nuijten, O. [ISSO, Rotterdam (Netherlands); Van Pelt, J. [Skiw, Nieuwegein (Netherlands); Arts, J. [Imtech Utiliteit West, Capelle a/d IJssel (Netherlands); Vollebregt, R.; Hoeffnagel, R.; Smorenburg, P.; Bijman, J.

    2007-02-15

    In eight articles attention is paid to several aspects of air conditioning and related systems: the perfect filter case for gas filtration, innovative cooling for computer rooms, thermal comfort in offices, standardization of legionella prevention in climate installations and cooling towers, air quality and energy consumption of integrated units, new air conditioners in the Dutch market. [Dutch] In acht artikelen wordt aandacht besteed aan verschillende aspecten van luchtbehandeling en verwante systemen: de perfecte filtercassette vor gasfasefiltratie, innovatieve koeling in computerruimte, hoog comfort in bestaande kantoren, de in ontwikkeling zijn ISSO-publicatie 55.3 voor legionellapreventie in klimaatinstallaties, legionellapreventie bij comfortkoeling, luchtbehandeling met geintegreerde units, en nieuwe luchtbehandelingskasten voor de Nederlandse markt.

  3. Legislative and regulatory developments on acoustic pollution air-conditioning plants; Sviluppi legislativi e normativi sull'inquinamento acustico: gli impianti di climatizzazione

    Energy Technology Data Exchange (ETDEWEB)

    Cocchi, A. [Bologna Univ., Bologna (Italy); Cocchi, A.; Cocchi, N. [Tecnologie per l' Ambiente Sas, Bologna (Italy)

    1999-11-01

    In recent years an increasing activity has developed around the subject {sup n}oise{sup ,} the metrology, the effects on the health and wellness of mankind, in living, working or resting environments. The problem of exposure to the noise has been faced according to different aspects and in different situations; to date it is managed by the reception in Italy of the so-called Direttiva Macchine (Machines directive). The paper proposes a reading applied to the air-conditioning sector. [Italian] Gli anni recenti hanno visto una attivita' sempre crescente attorno al tema del rumore, della sua metrologia, dei suoi effetti sulla salute e sul benessere dell'uomo, in ambiente di vita, di lavoro e di riposo. Il problema dell'esposizione a rumore e' stato affrontato secondo diversi aspetti e in diverse occasioni e si avvia a piena regolamentazione oggi con la pubblicazione di gran parte dei decreti attuativi della L. 447/95.

  4. Foliage Plants for Improving Indoor Air Quality

    Science.gov (United States)

    Wolverton, B. C.

    1988-01-01

    NASA's research with foliage houseplants during the past 10 years has produced a new concept in indoor air quality improvement. This new and exciting technology is quite simple. Both plant leaves and roots are utilized in removing trace levels of toxic vapors from inside tightly sealed buildings. Low levels of chemicals such as carbon monoxide and formaldehyde can be removed from indoor environments by plant leaves alone, while higher concentrations of numerous toxic chemicals can be removed by filtering indoor air through the plant roots surrounded by activated carbon. The activated carbon absorbs large quantities of the toxic chemicals and retains them until the plant roots and associated microorganisms degrade and assimilate these chemicals.

  5. Local Air Quality Conditions and Forecasts

    Science.gov (United States)

    ... Monitor Location Archived Maps by Region Canada Air Quality Air Quality on Google Earth Links A-Z About AirNow AirNow International Air Quality Action Days / Alerts AirCompare Air Quality Index (AQI) ...

  6. The Effect of Computers on School Air-Conditioning.

    Science.gov (United States)

    Fickes, Michael

    2000-01-01

    Discusses the issue of increased air-conditioning demand when schools equip their classrooms with computers that require enhanced and costlier air-conditioning systems. Air-conditioning costs are analyzed in two elementary schools and a middle school. (GR)

  7. The Effect of Computers on School Air-Conditioning.

    Science.gov (United States)

    Fickes, Michael

    2000-01-01

    Discusses the issue of increased air-conditioning demand when schools equip their classrooms with computers that require enhanced and costlier air-conditioning systems. Air-conditioning costs are analyzed in two elementary schools and a middle school. (GR)

  8. 某化纤厂KTC环境空调机组改造效果分析%Transformation effect analysis of KTC environment air-conditioning unit of one chemical fibre plant

    Institute of Scientific and Technical Information of China (English)

    卢贤生; 秦德科

    2012-01-01

    对某化纤厂KTC环境空调机组进行改造,取消原有的回风系统,采用全新风,利用气楼将回风全部排至室外.对改造前后的经济性和室内环境进行比较得知,初投资没有增加,每年的运行费用减少209万元,室内环境有很大的改善.%KTC environment air-conditioning unit of one chemical fibre plant is transformed,the primary air return system is dismantled,all fresh air is adopted and the clerestory to exhaust the returned air to outdoor is used. The consume and indoor environment is compared,the result shows that not only the investing is not increased, but also operation cost is decreasing 2. 09 million annual and indoor environment is improved.

  9. A mixed air/air and air/water heat pump system ensures the air-conditioning of a cinema; Un systeme mixte PAC air/air et air/eau climatise un cinema

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2001-03-01

    This article presents the air conditioning system of a new cinema complex of Boulogne (92, France) which comprises a double-flux air processing plant and two heat pumps. Each heat pump has two independent refrigerating loops: one with a air condenser and the other with a water condenser. This system allows to limit the power of the loop and to reduce the size of the cooling tower and of the vertical ducts. This article describes the technical characteristics of the installation: thermodynamic units, smoke clearing, temperature control, air renewing. (J.S.)

  10. Air Conditioning and Refrigeration. Book Two.

    Science.gov (United States)

    Wantiez, Gary W.

    This curriculum guide (book II), along with book I, is designed to provide students with the basic skills for an occupation in air conditioning and refrigeration. Six major areas are included, each consisting of one or more units of instruction. These areas and their respective units are titled as follows: Electricity (fundamentals of electricity,…

  11. Air Conditioning and Refrigeration Supplementary Units.

    Science.gov (United States)

    Winston, Del; And Others

    This document contains supplemental materials for special needs high school students intended to facilitate their mainstreaming in regular air conditioning and refrigeration courses. Teacher's materials precede the materials for students and include general notes for the instructor, additional suggestions, two references, a questionnaire on the…

  12. Air Conditioning and Refrigeration Book IV.

    Science.gov (United States)

    Eckes, William; Fulkerson, Dan

    This publication is the concluding text in a four-part curriculum for air conditioning and refrigeration. Materials in Book 4 are designed to complement theoretical and functional elements in Books 1-3. Instructional materials in this publication are written in terms of student performance using measurable objectives. The course includes six…

  13. Fundamentals of Air Conditioning and Refrigeration.

    Science.gov (United States)

    Clemons, Mark

    This set of instructional materials provides secondary and postsecondary students with a state-of-the-art curriculum for the air conditioning and refrigeration industry that includes the many changes brought by new Environmental Protection Agency (EPA) regulations. Introductory materials explain the use of this publication and provide the…

  14. Readings in Air Conditioning and Refrigeration.

    Science.gov (United States)

    Uberto, Jeffrey A.

    Designed to encourage vocational high school students to read by offering reading materials relevant to their vocational goals, this document contains thirty-seven articles related to air conditioning and refrigeration which have been selected from trade journals, magazines, and newspapers and adapted to the students' reading capabilities. A…

  15. 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…

  16. Smart sensors enable smart air conditioning control.

    Science.gov (United States)

    Cheng, Chin-Chi; Lee, Dasheng

    2014-06-24

    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.

  17. Evaporative Condensers in Comfortable Air Conditioning System

    Institute of Scientific and Technical Information of China (English)

    YIN Ying-de; ZHU Dong-sheng; DU Gui-mei; LI Yuan-xi; SUN He-jing; LIU Qing-ming

    2009-01-01

    The operating theory of an evaporative condenser was expatiated.The difference between an e-vaporative condensing refrigeration system and a general refrigeration system was analyzed.Compared with the air-cooled and the water-cooled,the virtues of energy-conservation and water-conservation of evaporative con-densers were analyzed.Some questions existing in the application of evaporative condensers were pointed out,the corresponding solving methods were analyzed accordingly,and the development trend of evaporative con-densing technique in mechanical refrigeration system field and the applied foreground of evaporative condensers in comfortable air conditioning were prospected.

  18. Air Conditioning System using Rankine Cycle

    Science.gov (United States)

    Nagatomo, Shigemi; Yamaguchi, Hiroichi; Hattori, Hitoshi; Futamura, Motonori

    Natural gas is used as the energy source to cope with the recent situation of increasing demand for electricity especially in summer. In this paper, the performance of a Rankine cycle air conditioning system driven by natural gas was studied. The following results were obtained : (1) Basic equations of performance, refrigerant mass flow rate and expander volume were developed by using the values of heating efficiency, regeneration efficiency, expander efficiency and compressor efficiency. (2) R134a refrigerant has been considered to be suitable for the Rankine cycle air conditioning system, compared with other refrigerants. (3)A Rankine cycle cooling system using R134a refrigerant as a single working fluid was developed. System COP of 0.47 was attained at typical operating condition.

  19. Air pollution impedes plant-to-plant communication by volatiles.

    Science.gov (United States)

    Blande, James D; Holopainen, Jarmo K; Li, Tao

    2010-09-01

    Volatile organic compounds (VOCs) emitted by damaged plants convey information to undamaged neighbouring plants, and previous research has shown that these signals are effective over short distances in nature. Many herbivore-induced VOCs react with ozone, which is the most important tropospheric air pollutant in rural areas. We used extrafloral nectar (EFN) secretion as a phenotypic indicator of between-plant communication in Phaseolus lunatus L. (Lima bean) and show that an ozone-rich (80 ppb) atmosphere reduces the distance over which signalling occurs. We found that ozone degrades several herbivore-induced VOCs, a likely mechanism reducing communication distances. Direct exposure to 80-ppb ozone did not affect the VOC emissions from P. lunatus. In addition, we demonstrated that high ozone concentrations, 120 and 160 ppb, induced EFN secretion in exposed plants, whereas more moderate concentrations, 80 and 100 ppb, did not. This suggests that ozone can play a complex role in the indirect defence of P. lunatus.

  20. Numerical simulation and nasal air-conditioning

    Directory of Open Access Journals (Sweden)

    Keck, Tilman

    2010-01-01

    Full Text Available Heating and humidification of the respiratory air are the main functions of the nasal airways in addition to cleansing and olfaction. Optimal nasal air conditioning is mandatory for an ideal pulmonary gas exchange in order to avoid desiccation and adhesion of the alveolar capillary bed. The complex three-dimensional anatomical structure of the nose makes it impossible to perform detailed in vivo studies on intranasal heating and humidification within the entire nasal airways applying various technical set-ups. The main problem of in vivo temperature and humidity measurements is a poor spatial and time resolution. Therefore, in vivo measurements are feasible only to a restricted extent, solely providing single temperature values as the complete nose is not entirely accessible. Therefore, data on the overall performance of the nose are only based on one single measurement within each nasal segment. In vivo measurements within the entire nose are not feasible. These serious technical issues concerning in vivo measurements led to a large number of numerical simulation projects in the last few years providing novel information about the complex functions of the nasal airways. In general, numerical simulations merely calculate predictions in a computational model, e.g. a realistic nose model, depending on the setting of the boundary conditions. Therefore, numerical simulations achieve only approximations of a possible real situation. The aim of this review is the synopsis of the technical expertise on the field of in vivo nasal air conditioning, the novel information of numerical simulations and the current state of knowledge on the influence of nasal and sinus surgery on nasal air conditioning.

  1. Innovative Air Conditioning and Climate Control

    Science.gov (United States)

    Graf, John

    2015-01-01

    NASA needed to develop a desiccant wheel based humidity removal system to enable the long term testing of the Orion CO2 scrubber on the International Space Station. In the course of developing that system, we learned three things that are relevant to energy efficient air conditioning of office towers. NASA developed a conceptual design for a humidity removal system for an office tower environment. We are looking for interested partners to prototype and field test this concept.

  2. Seminar 14 - Desiccant Enhanced Air Conditioning: Desiccant Enhanced Evaporative Air Conditioning (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Kozubal, E.

    2013-02-01

    This presentation explains how liquid desiccant based coupled with an indirect evaporative cooler can efficiently produce cool, dry air, and how a liquid desiccant membrane air conditioner can efficiently provide cooling and dehumidification without the carryover problems of previous generations of liquid desiccant systems. It provides an overview to a liquid desiccant DX air conditioner that can efficiently provide cooling and dehumidification to high latent loads without the need for reheat, explains how liquid desiccant cooling and dehumidification systems can outperform vapor compression based air conditioning systems in hot and humid climates, explains how liquid desiccant cooling and dehumidification systems work, and describes a refrigerant free liquid desiccant based cooling system.

  3. 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.

  4. 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.

  5. Industrial air conditioning dossier; Dossier Clim industrielle

    Energy Technology Data Exchange (ETDEWEB)

    Nicolas, J.

    2004-04-01

    Because each industrial process is different and has its own specificities, the question of air conditioning in the industry must be considered in a global way and has to take into consideration the different steps of the process and the expectations of prime contractors which, today, pay more attention to the environmental and energy saving aspects. The cooling towers, even if much debated today, remain one of the most efficient solution for high power installations. This dossier presents three examples of realizations: a newspaper printing workshop which requires a precise regulation of temperature and hygrometry, the huge volume workshop of an aerospace company with important solar and internal heat loads, and the painting workshop of a car making company which requires a rigorous control of temperature, humidity and dust content of the ambient air. (J.S.)

  6. Changes in alpine plant growth under future climate conditions

    Directory of Open Access Journals (Sweden)

    A. Rammig

    2010-06-01

    Full Text Available Alpine shrub- and grasslands are shaped by extreme climatic conditions such as a long-lasting snow cover and a short vegetation period. Such ecosystems are expected to be highly sensitive to global environmental change. Prolonged growing seasons and shifts in temperature and precipitation are likely to affect plant phenology and growth. In a unique experiment, climatology and plant growth was monitored for almost a decade at 17 snow meteorological stations in different alpine regions along the Swiss Alps. Regression analyses revealed highly significant correlations between mean air temperature in May/June and snow melt out, onset of plant growth, and plant height. These correlations were used to project plant growth phenology for future climate conditions based on the gridded output of a set of regional climate models runs. Melt out and onset of growth were projected to occur on average 17 days earlier by the end of the century than in the control period from 1971–2000 under the future climate conditions of the low resolution climate model ensemble. Plant height and biomass production were expected to increase by 77% and 45%, respectively. The earlier melt out and onset of growth will probably cause a considerable shift towards higher growing plants and thus increased biomass. Our results represent the first quantitative and spatially explicit estimates of climate change impacts on future growing season length and the respective productivity of alpine plant communities in the Swiss Alps.

  7. Automatic air flow control in air conditioning ducts

    Science.gov (United States)

    Obler, H. D.

    1972-01-01

    Device is designed which automatically selects air flow coming from either of two directions and which can be adjusted to desired air volume on either side. Device uses one movable and two fixed scoops which control air flow and air volume.

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

    Science.gov (United States)

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

    2004-05-05

    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 microm), 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 microg/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

  9. [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.

  10. Refrigeration, Heating & Air Conditioning. Post Secondary Curriculum Guide.

    Science.gov (United States)

    Garrison, Joe C.; And Others

    This curriculum guide was designed for use in postsecondary refrigeration, heating and air conditioning education programs in Georgia. Its purpose is to provide for the development of entry level skills in refrigeration, heating, and air conditioning in the areas of air conditioning knowledge, theoretical structure, tool usage, diagnostic ability,…

  11. Interior Landscape Plants for Indoor Air Pollution Abatement

    Science.gov (United States)

    Wolverton, B. C.; Johnson, Anne; Bounds, Keith

    1989-01-01

    In this study, the leaves, roots, soil, and associated microorganisms of plants have been evaluated as a possible means of reducing indoor air pollutants. Additionally, a novel approach of using plant systems for removing high concentrations of indoor air pollutants such as cigarette smoke, organic solvents, and possibly radon has been designed from this work. This air filter design combines plants with an activated carbon filter. The rationale for this design, which evolved from wastewater treatment studies, is based on moving large volumes of contaminated air through an activated carbon bed where smoke, organic chemicals, pathogenic microorganisms (if present), and possibly radon are absorbed by the carbon filter. Plant roots and their associated microorganisms then destroy the pathogenic viruses, bacteria, and the organic chemicals, eventually converting all of these air pollutants into new plant tissue. It is believed that the decayed radon products would be taken up the plant roots and retained in the plant tissue.

  12. 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

  13. On the history of air conditioning; Zur Geschichte der Raumklimatechnik

    Energy Technology Data Exchange (ETDEWEB)

    Fitzner, Klaus; Finke, Ulrich [Klimakonzept Ingenieurgesellschaft, Berlin (Germany)

    2010-01-15

    The theoretical bases of indoor air conditioning originates from the time of enlightenment (Lavoisier 1792). For the first time air conditioning is applied 1836 in the House of Commons in London. Wide application begins in the USA in the 1930s, in Germany due to the war after the 1950s. Starting from 1970 there are advancements in Germany and Northern Europe, which make it possible not to only air-condition but to fulfil thermally comfortable conditions. (orig.)

  14. 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.

  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. 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,…

  17. The air-conditioning capacity of the human nose.

    Science.gov (United States)

    Naftali, Sara; Rosenfeld, Moshe; Wolf, Michael; Elad, David

    2005-04-01

    The nose is the front line defender of the respiratory system. Unsteady simulations in three-dimensional models have been developed to study transport patterns in the human nose and its overall air-conditioning capacity. The results suggested that the healthy nose can efficiently provide about 90% of the heat and the water fluxes required to condition the ambient inspired air to near alveolar conditions in a variety of environmental conditions and independent of variations in internal structural components. The anatomical replica of the human nose showed the best performance and was able to provide 92% of the heating and 96% of the moisture needed to condition the inspired air to alveolar conditions. A detailed analysis explored the relative contribution of endonasal structural components to the air-conditioning process. During a moderate breathing effort, about 11% reduction in the efficacy of nasal air-conditioning capacity was observed.

  18. Stem sap flow in plants under low gravity conditions

    Science.gov (United States)

    Tokuda, Ayako; Hirai, Hiroaki; Kitaya, Yoshiaki

    2016-07-01

    A study was conducted to obtain a fundamental knowledge for plant functions in bio-regenerative life support systems in space. Stem sap flow in plants is important indicators for water transport from roots to atmosphere through leaves. In this study, stem sap flow in sweetpotato was assessed at gravity levels from 0.01 to 2 g for about 20 seconds each during parabolic airplane flights. Stem sap flow was monitored with a heat balance method in which heat generated with a tiny heater installed in the stem was transferred upstream and downstream by conduction and upstream by convection with the sap flow through xylems of the vascular tissue. Thermal images of stem surfaces near heated points were captured using infrared thermography and the internal heat convection corresponding to the sap flow was analyzed. In results, the sap flow in stems was suppressed more at lower gravity levels without forced air circulation. No suppression of the stem sap flow was observed with forced air circulation. Suppressed sap flow in stems would be caused by suppression of transpiration in leaves and would cause restriction of water and nutrient uptake in roots. The forced air movement is essential to culture healthy plants at a high growth rate under low gravity conditions in space.

  19. Possible Economies in Air-Conditioning by Accepting Temperature Swings.

    Science.gov (United States)

    Loudon, A. G.; Petherbridge, P.

    Public building air conditioning systems, which use constant and varying heat and cooling loads, are compared and investigated. Experiments indicated that constant temperature controls based on outside air temperature alone were inefficient. Ventilating a building with outside air and the methods of doing so are cited as being the most economical…

  20. Vibration Analysis of Air Condition Unit on Subway

    Directory of Open Access Journals (Sweden)

    Yan Liu

    2013-06-01

    Full Text Available Subway system has many merits including large passenger carrying ability, high speed, strong controllability and reliability of driving. Nevertheless, subways also have brought many disadvantages for human. In many subway systems, noisy environments are clearly observed and passengers are exposed to higher noise levels than permissible limit. This study presents a study of noise and vibration of subway air condition system, so as to grasp the vibration distribution laws of the air condition system. By the tested of noise and vibration, the researcher find the sound distribution rule of air condition is very important Based on the consequence of the testing, the acceleration of air condition has little to do with the subway speed and more to do with the vibration of fan; When the train driving on the viaduct bridge, the acceleration of air condition is biggish in 125 Hz and In 50-1000 Hz the vibration of air condition is obviously. When the train running underground line, as a result of the resonance of body, air condition’s vibration is biggish in 630 Hz and the vibration is obviously in 125-1250 Hz. With the increase of the speed, the influence of the ground’s second radiation on body vibration is enhanced. The superfine gross wool which is used to air condition can achieve good results for noise reduction. This research has higher reference for the vibration and noise reduction of the subway air condition system.

  1. Air conditioning and blowers. Special issue; Airconditioning en ventilatoren. Themanummer

    Energy Technology Data Exchange (ETDEWEB)

    Nekeman, H.E. [Multi Import, Rotterdam (Netherlands); Hol, M. [Aircool Klimaattechniek, Ridderkerk (Netherlands); Bassa, E. [ed.

    1997-06-01

    In four articles several aspects of air conditioners and blowers are discussed: the application of the newly developed electronically commutated direct current engine in high-efficiency boilers, air conditioners and cooling systems, the future for flexible synthetic cooling pipes, a description of a Mitsubishi-developed air conditioner: the Inverter Driven Multi-indoor unit, also known as the KX-system, and the importance of the private sector (houses, small businesses, cars) for the use of air conditioning installations. 8 figs.

  2. Plant growth conditions alter phytolith carbon

    Directory of Open Access Journals (Sweden)

    Kimberley L Gallagher

    2015-09-01

    Full Text Available Many plants, including grasses and some important human food sources, accumulate and precipitate silica in their cells to form opaline phytoliths. These phytoliths contain small amounts of organic matter (OM that are trapped during the process of silicification. Previous work has suggested that plant silica is associated with compounds such as proteins, lipids, lignin and carbohydrate complexes. It is not known whether these compounds are cellular components passively encapsulated as the cell silicifies, polymers actively involved in the precipitation process or random compounds assimilated by the plant and discarded into a glass wastebasket. Here, we used Raman spectroscopy to map the distribution of OM in phytoliths, and to analyze individual phytoliths isolated from Sorghum bicolor plants grown under different laboratory treatments. Using mapping, we showed that OM in phytoliths is distributed throughout the silica and is not related to dark spots visible in light microscopy, previously assumed to be the repository for phytolith OM. The Raman spectra exhibited common bands indicative of C-H stretching modes of general OM, and further more diagnostic bands consistent with carbohydrates, lignins and other OM. These Raman spectra exhibited variability of spectral signatures and of relative intensities between sample treatments indicating that differing growth conditions altered the phytolith carbon. This may have strong implications for understanding the mechanism of phytolith formation, and for use of phytolith carbon isotope values in dating or paleoclimate reconstruction.

  3. Plant growth conditions alter phytolith carbon.

    Science.gov (United States)

    Gallagher, Kimberley L; Alfonso-Garcia, Alba; Sanchez, Jessica; Potma, Eric O; Santos, Guaciara M

    2015-01-01

    Many plants, including grasses and some important human food sources, accumulate, and precipitate silica in their cells to form opaline phytoliths. These phytoliths contain small amounts of organic matter (OM) that are trapped during the process of silicification. Previous work has suggested that plant silica is associated with compounds such as proteins, lipids, lignin, and carbohydrate complexes. It is not known whether these compounds are cellular components passively encapsulated as the cell silicifies, polymers actively involved in the precipitation process or random compounds assimilated by the plant and discarded into a "glass wastebasket." Here, we used Raman spectroscopy to map the distribution of OM in phytoliths, and to analyze individual phytoliths isolated from Sorghum bicolor plants grown under different laboratory treatments. Using mapping, we showed that OM in phytoliths is distributed throughout the silica and is not related to dark spots visible in light microscopy, previously assumed to be the repository for phytolith OM. The Raman spectra exhibited common bands indicative of C-H stretching modes of general OM, and further more diagnostic bands consistent with carbohydrates, lignins, and other OM. These Raman spectra exhibited variability of spectral signatures and of relative intensities between sample treatments indicating that differing growth conditions altered the phytolith carbon. This may have strong implications for understanding the mechanism of phytolith formation, and for use of phytolith carbon isotope values in dating or paleoclimate reconstruction.

  4. 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.

  5. Section 609 of the Clean Air Act: Motor Vehicle Air Conditioning

    Science.gov (United States)

    Fact sheet provides a general overview of EPA regulations under Section 609 of the Clean Air Act, which is focused on preventing the release of refrigerants during the servicing of motor vehicle air-conditioning systems and similar appliances.

  6. 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…

  7. Energy Efficiency for Heating, Ventilating, Air-Conditioning Instructors.

    Science.gov (United States)

    Scharmann, Larry, Ed.; Lay, Gary, Ed.

    Intended primarily but not solely for use at the postsecondary level, this curriculum guide contains five units on energy efficiency that were designed to be incorporated into an existing program in heating, ventilating, and air-conditioning. The following topics are examined: how energy conservation pays, heating, ventilation, air-conditioning,…

  8. 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)

  9. Application of solar energy to air-conditioning

    Science.gov (United States)

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

    1978-01-01

    Results of survey of application of solar energy to air-conditioning systems are summarized in report. Survey reviewed air-conditioning techniques that are most likely to find residential applications and that are compatible with solar-energy systems being developed.

  10. 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)

  11. Energy Efficiency for Heating, Ventilating, Air-Conditioning Instructors.

    Science.gov (United States)

    Scharmann, Larry, Ed.; Lay, Gary, Ed.

    Intended primarily but not solely for use at the postsecondary level, this curriculum guide contains five units on energy efficiency that were designed to be incorporated into an existing program in heating, ventilating, and air-conditioning. The following topics are examined: how energy conservation pays, heating, ventilation, air-conditioning,…

  12. Air Conditioning and Refrigeration Program Articulation, 1981-1982.

    Science.gov (United States)

    Dallas County Community Coll. District, TX.

    Based on a survey of high school programs and courses in the Dallas County Community College District (DCCCD), this articulated program is designed to prepare students for entry-level employment in the air conditioning and refrigeration industry, including residential and commercial air conditioning and commercial refrigeration. The skills and…

  13. Hospital-acquired infections associated with poor air quality in air-conditioned environments

    OpenAIRE

    Daniela Pinheiro da Silva

    2014-01-01

    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-acqui...

  14. Solar-powered air-conditioning

    Science.gov (United States)

    Clark, D. C.; Rousseau, J.

    1977-01-01

    Report focuses on recent study on development of solar-powered residential air conditioners and is based on selected literature through 1975. Its purposes are to characterize thermal and mechanical systems that might be useful in development of Rankine-cycle approach to solar cooling and assessment of a Lithium Bromide/Water absorption cycle system.

  15. Temperature Difference Between the Air and Organs of Rice Plant and Its Relation to Spikelet Fertility

    Institute of Scientific and Technical Information of China (English)

    YAN Chuan; DING Yan-feng; LIU Zheng-hui; WANG Qiang-sheng; LI Gang-hua; HE Ying; WANG Shao-hua

    2008-01-01

    Based on the experiment of measuring panicles and leaves, air temperature, and humidity above the canopy of rice cultivars after heading in 2005 and 2006, we investigated the temperature difference (TD) between the air and organs of rice plant and its relationship with spikelet fertility. The results showed that TDs between the air and organs of rice varied with air temperature, air humidity, and plant type. For similar air humidity, TDs were lower at the air temperature of 28.5℃ than at higher temperature of 35.5℃, whereas for the same air temperature, the TDs decreased as the air humidity increased. TDs were also affected by plant type of the cultivars. Erect panicle cultivars showed higher TDs than those with droopy panicles under similar climatic conditions, and cultivars with panicles above flag leaf (PAFL) had higher TDs than those with panicles below the flag leaf (PBFL). Cultivars grown in a location with lower air humidity and higher temperature, such as Taoyuan, China, had higher spikelet fertility than those in higher humidity under the similar air temperature during the grain filling stage. This is partially attributed to the larger TDs under the lower humidity. Row-spacing and the ratio of basal-tillering to panicle-spikelet fertilizer showed a significant influence on TD and subsequently on spikelet fertility, suggesting the possibility of increasing spikelet fertility by agronomic management.

  16. Air and the origin of the experimental plant physiology.

    Science.gov (United States)

    Pennazio, Sergio

    2005-01-01

    It is well known that oxygen and carbon dioxide are two chemicals which enter the plant metabolism as nutrients. The bases of this nowadays obvious statement were placed in the 18th century by means of the works of ingenious naturalists such as Robert Boyle, Stephen Hales, Joseph Priestley, Jam Ingenhousz, Lazzaro Spallanzani and Theodore De Saussure. Till the end of the 17th century, the atmospheric air was considered as an ineffable spirit, the function of which was of physical nature. Boyle was the first naturalist to admit the possibility that respiration were an exchange of vapours occurring in the blood. Stephen Hales realised that air could be fixed by plants under the influence of solar light. Priestley showed that plants could regenerate the bad air making it breathable. Ingenhousz demonstrated that the green parts of plants performed the complete purification of air only under the influence of the light. Spallanzani discovered that plants respire and guessed that the good air (oxygen) originated from the fixed air (carbon dioxide). Finally, Theodore De Saussure showed that plants were able to adsorb carbon dioxide and to release oxygen in a proportional air. All these discoveries benefited of the results coming from investigations of scholars of the so-called "pneumatic chemistry" (Boyle himself, George Ernst Stahl, Joseph Black, Priestley himself, and many more others. But among all the eminent scientists above mentioned stands out the genius of Antoine Laurent Lavoisier, who revolutionised the chemistry of the 18th century ferrying it towards the modern chemistry.

  17. Energy consumption in air-conditioning; Improvement and Reduction

    Directory of Open Access Journals (Sweden)

    Yacoub Yousef Ahmad Alotaibi

    2015-06-01

    Full Text Available Anew technique to reduce latent heat to improve energy consumption in air-conditioning is by using Desiccant . The aim of dehumidification process is to remove the water vapor from the processed air to liquid desiccants. Dehumidification is considered as a key feature of HVAC systems for thermal comfort. Chemical dehumidification is remove the water vapour from the air by transferring it towards a desiccant material (adsorption or absorption. Results illustrate that the application of liquid desiccant in air conditioning can improve indoor air quality, reduce energy consumption and bring environmentally friendly products, also. Lewis number increased rapidly with the increase of solution concentration Therefore liquid desiccant air conditioning systems are drawing more and more attention in recent years.

  18. 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.

  19. Does air conditioning impact on hygienic quality of indoor air on seagoing vessels?

    Science.gov (United States)

    Meyer, Gabriele; Schepers, Bernd-Fred

    2007-01-01

    According to observations by occupational health physicians, nearly 50 % of the seamen on German vessels will get diseases of the upper respiratory tract. An impact of the air-conditioning systems on these diseases has been suggested. To examine the hygienic quality of indoor air on seagoing vessels, a pilot study was initiated by the See-Berufsgenossenschaft. Air samples were taken on-site at different sampling sites and analysed for the occurrence of microorganisms. Bacteria showed the highest cell numbers and the highest distribution in indoor air on vessels, whereby the maximum level was determined in the air of crew cabins. The identification of bacteria showed that beside common airborne species, pathogens existed. Air-conditioning seems to influence the quality of indoor air on seagoing vessels. Interim results of the study indicate that regular maintenance of air-conditioning systems is essential.

  20. Air-conditioning in the human nasal cavity.

    Science.gov (United States)

    Elad, David; Wolf, Michael; Keck, Tilman

    2008-11-30

    Healthy humans normally breathe through their nose even though its complex geometry imposes a significantly higher resistance in comparison with mouth breathing. The major functional roles of nasal breathing are defense against infiltrating particles and conditioning of the inspired air to nearly alveolar conditions in order to maintain the internal milieu of the lung. The state-of-the-art of the existing knowledge on nasal air-conditioning will be discussed in this review, including in vivo measurements in humans and computational studies on nasal air-conditioning capacity. Areas where further studies will improve our understanding and may help medical diagnosis and intervention in pathological states will be introduced.

  1. Which ornamental plant species effectively remove benzene from indoor air?

    Science.gov (United States)

    Liu, Yan-Ju; Mu, Yu-Jing; Zhu, Yong-Guan; Ding, Hui; Crystal Arens, Nan

    Phytoremediation—using plants to remove toxins—is an attractive and cost effective way to improve indoor air quality. This study screened ornamental plants for their ability to remove volatile organic compounds from air by fumigating 73 plant species with 150 ppb benzene, an important indoor air pollutant that poses a risk to human health. The 10 species found to be most effective at removing benzene from air were fumigated for two more days (8 h per day) to quantify their benzene removal capacity. Crassula portulacea, Hydrangea macrophylla, Cymbidium Golden Elf., Ficus microcarpa var. fuyuensis, Dendranthema morifolium, Citrus medica var. sarcodactylis, Dieffenbachia amoena cv. Tropic Snow; Spathiphyllum Supreme; Nephrolepis exaltata cv. Bostoniensis; Dracaena deremensis cv. Variegata emerged as the species with the greatest capacity to remove benzene from indoor air.

  2. 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.

  3. AIR DISPERSION MODELING AT THE WASTE ISOLATION PILOT PLANT

    Energy Technology Data Exchange (ETDEWEB)

    Rucker, D.F.

    2000-08-01

    One concern at the Waste Isolation Pilot Plant (WIPP) is the amount of alpha-emitting radionuclides or hazardous chemicals that can become airborne at the facility and reach the Exclusive Use Area boundary as the result of a release from the Waste Handling Building (WHB) or from the underground during waste emplacement operations. The WIPP Safety Analysis Report (SAR), WIPP RCRA Permit, and WIPP Emergency Preparedness Hazards Assessments include air dispersion calculations to address this issue. Meteorological conditions at the WIPP facility will dictate direction, speed, and dilution of a contaminant plume of respirable material due to chronic releases or during an accident. Due to the paucity of meteorological information at the WIPP site prior to September 1996, the Department of Energy (DOE) reports had to rely largely on unqualified climatic data from the site and neighboring Carlsbad, which is situated approximately 40 km (26 miles) to the west of the site. This report examines the validity of the DOE air dispersion calculations using new meteorological data measured and collected at the WIPP site since September 1996. The air dispersion calculations in this report include both chronic and acute releases. Chronic release calculations were conducted with the EPA-approved code, CAP88PC and the calculations showed that in order for a violation of 40 CFR61 (NESHAPS) to occur, approximately 15 mCi/yr of 239Pu would have to be released from the exhaust stack or from the WHB. This is an extremely high value. Hence, it is unlikely that NESHAPS would be violated. A site-specific air dispersion coefficient was evaluated for comparison with that used in acute dose calculations. The calculations presented in Section 3.2 and 3.3 show that one could expect a slightly less dispersive plume (larger air dispersion coefficient) given greater confidence in the meteorological data, i.e. 95% worst case meteorological conditions. Calculations show that dispersion will decrease

  4. Performance analysis of a liquid desiccant and membrane contactor hybrid air-conditioning system

    Energy Technology Data Exchange (ETDEWEB)

    Bergero, Stefano; Chiari, Anna [DIPARC, Faculty of Architecture, University of Genoa, Stradone S. Agostino 37, 16123 Genova (Italy)

    2010-11-15

    The present study examines the performances of a hybrid air-conditioning system in which a vapour-compression inverse cycle is integrated with an air dehumidification system working with hygroscopic solution and hydrophobic membrane. This model may be a valid alternative to traditional summertime air-conditioning system, in which the air is cooled to below its dew-point temperature and subsequently reheated. The proposed hybrid system involves simultaneously cooling and dehumidifying the air conveyed to the conditioned ambient in an air-solution membrane contactor. An LiCl solution is cooled by means of a vapour-compression inverse cycle using the refrigerant KLEA 407C. The solution is regenerated in another membrane contactor by exploiting the heat rejected by the condenser. A SIMULINK calculation programme was designed in order to simulate the system under examination in steady-state conditions. The performances of the system were analysed on varying a few significant operating parameters, and were compared with those of a traditional direct-expansion air-conditioning plant in typical summertime conditions. The results of the simulations revealed significant energy savings, which, in particular operating conditions, may exceed 50%. (author)

  5. Experimental tests of a gas fired adsorption air conditioning system

    Energy Technology Data Exchange (ETDEWEB)

    Poyelle, F.; Guilleminot, J.J.; Meunier, F. [C.N.R.S.-L.I.M.S.I., Orsay Cedex (France); Canal, P.; Soide, I.; Klemsdal, E. [Gaz de Francer Saint Denis La Plaine (France)

    1997-10-01

    Over recent years, there has been growing interest for air conditioning systems, for commercial and offices buildings, transport and residential houses. Gaz de France promote natural gas powered air conditioning systems through the installation of commercial absorption machines, producing chilled and/or hot water. These machines cover loads from 70 kW to 5 MW. Gaz de France`s purpose is to develop a small scale natural gas fueled air conditioning system for residential applications and small commercials (5-20 kW). In order to study the feasibility of a small scale adsorption machine, a prototype has been studied, designed, constructed and tested. (au) 11 refs.

  6. Simulation technology for refrigeration and air conditioning appliances

    Institute of Scientific and Technical Information of China (English)

    DING Guoliang

    2006-01-01

    Simulation technology has been widely used for performance prediction and optimal design of refrigeration and air conditioning appliances. A brief history of simulation technology for refrigeration and air conditioning appliances is reviewed. The models for evaporator, condenser, compressor, capillary tube and thermal insulation layer are summarized, and a fast calculation method for thermodynamic properties of refrigerant is introduced in this paper. The model-based intelligent simulation technology and the simulation technology based on graph theory are also illustrated. Finally, an updated trend of simulation technology development for refrigeration and air conditioning appliances is discussed.

  7. Desiccant Enhanced Evaporative Air Conditioning: Parametric Analysis and Design; Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Woods, J.; Kozubal, E.

    2012-10-01

    This paper presents a parametric analysis using a numerical model of a new concept in desiccant and evaporative air conditioning. The concept consists of two stages: a liquid desiccant dehumidifier and a dew-point evaporative cooler. Each stage consists of stacked air channel pairs separated by a plastic sheet. In the first stage, a liquid desiccant film removes moisture from the process (supply-side) air through a membrane. An evaporatively-cooled exhaust airstream on the other side of the plastic sheet cools the desiccant. The second-stage indirect evaporative cooler sensibly cools the dried process air. We analyze the tradeoff between device size and energy efficiency. This tradeoff depends strongly on process air channel thicknesses, the ratio of first-stage to second-stage area, and the second-stage exhaust air flow rate. A sensitivity analysis reiterates the importance of the process air boundary layers and suggests a need for increasing airside heat and mass transfer enhancements.

  8. Solar air conditioning: introduction and basics; Solare Klimatisierung Einfuehrung und Grundlagen

    Energy Technology Data Exchange (ETDEWEB)

    Albers, J. [Inst. fuer Erhaltung und Modernisierung von Bauwerken e.V. an der Technische Univ. Berlin (Germany)

    2005-07-01

    A considerable increase of the cold energy demand is expected world-wide in the coming years. Electrically operated cold compression plants are currently used at the most in order to meet the cold energy demand resulting also in a rising electric current and primary energy demand. This can have an effect on the supply security as well as on the change of the world climate. Therefore more alternative methods of cold generation are supposed to be applied in the future. The following contribution describes that plant systems for solar air conditioning (SAC-systems) are an attractive and feasible technology that demands engineering but can also be further developed and can make an important contribution to the target mentioned above. First an overview is provided of conventional air conditioning technology and of the expected development tendencies with regard to cold demand. Afterwards the currently available solar air conditioning methods and their possible applications are explained. (orig.)

  9. Performance and evaluation of desiccant based air conditioning system.

    Directory of Open Access Journals (Sweden)

    Gaurav S. Wani

    2014-12-01

    Full Text Available This Project work presents study and experimental analysis of Desiccant based air conditioning system.The main purpose of this project is to increase the efficency of air conditioning system.In the convenstional air conditioning system cooling coli has two load latent load and sensible load. Cooling has to cool the air and simultaneously to dehumidify it.It increases load on cooling coil and affects performance to the system. To increase the efficiency the air conditioning system desiccant materials are used at the inlet of the air conditioning test rig. Desiccant materials attract moisture based on differences in vapor pressure. Due to their enormous affinity to absorb water and considerable ability to hold water. Due to use of desiccant material load on the cooling coil reduces since moisture is absorbed by desiccant; cooling coil has to take only sensible load. Analysis is done using different desiccant materials and based on the observation, power consumption before and after desiccant is calculated. From this conclusion is made that desiccant material improves the efficiency of air conditioning test rig

  10. Deposition of heavy water vapor from air to plant and soil

    Energy Technology Data Exchange (ETDEWEB)

    Andoh, Mariko; Amano, Hikaru [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Ichimasa, Michiko; Ichimasa, Yusuke

    1999-03-01

    When tritium is released into the atmosphere, plants play an important role in processes of tritium transfer in the environment. However, available data is limited because the uptake of tritium into a plant is affected by many factors such as plant growth, humidity, solar radiation, stomatal condition - all of which vary in daily and seasonal cycles. Deuterium, a stable isotope of tritium, was released as a tracer of tritium in the form of D{sub 2}O vapor in a greenhouse to study the transfer of tritium from air to plants and soils. The deposition rate of D{sub 2}O from the air to plant leaves was measured in a daytime and in a nighttime, and the results were compared. After D{sub 2}O release stopped, decline of D{sub 2}O concentrations in plant free water was measured. (author)

  11. MARANGONI CONVECTION AROUND A VENTILATED AIR BUBBLE UNDER MICROGRAVITY CONDITIONS

    NARCIS (Netherlands)

    HOEFSLOOT, HCJ; JANSSEN, LPBM; HOOGSTRATEN, HW

    Under microgravity conditions in both parabolic and sounding rocket flights, the mass-transfer-induced Marangoni convection around an air bubble was studied. To prevent the bubble from becoming saturated, the bubble was ventilated. It turned out that the flow rate of the air through the bubble

  12. 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.

  13. Transitioning to Low-GWP Alternatives in Unitary Air Conditioning

    Science.gov (United States)

    This fact sheet provides current information on low-Global Warming Potential (GWP) refrigerant alternatives used in unitary air-conditioning equipment, relevant to the Montreal Protocol on Substances that Deplete the Ozone Layer.

  14. Persistence of Initial Conditions in Continental Scale Air Quality Simulations

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset contains the data used in Figures 1 – 6 and Table 2 of the technical note "Persistence of Initial Conditions in Continental Scale Air Quality...

  15. Poor weather conditions and flight operations: Implications for air ...

    African Journals Online (AJOL)

    Poor weather conditions and flight operations: Implications for air transport hazard ... Ethiopian Journal of Environmental Studies and Management ... fog, dust haze and line squall that affect flight operation such as flight delays, diversion and ...

  16. Indoor Air Purification by Potted Plants

    DEFF Research Database (Denmark)

    Dela Cruz, Majbrit

    Volatile organic compounds (VOC) are ubiquitous in the indoor environment and can affect human health negatively. Potted plants are a potential green technology solution for removal of VOCs. This PhD project aimed at reviewing current literature on VOC removal by potted plants, developing a dynam...... community structure was, however, not the same for two consecutive experiments indicating that several bacteria can degrade VOCs...

  17. Application of Solar Energy to Air Conditioning Systems

    Energy Technology Data Exchange (ETDEWEB)

    M, Nash J; J, Harstad A

    1976-11-01

    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.

  18. 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.

  19. Extreme conditions in a dissolving air nanobubble

    Science.gov (United States)

    Yasui, Kyuichi; Tuziuti, Toru; Kanematsu, Wataru

    2016-07-01

    Numerical simulations of the dissolution of an air nanobubble in water have been performed taking into account the effect of bubble dynamics (inertia of the surrounding liquid). The presence of stable bulk nanobubbles is not assumed in the present study because the bubble radius inevitably passes the nanoscale in the complete dissolution of a bubble. The bubble surface is assumed to be clean because attachment of hydrophobic materials on the bubble surface could considerably change the gas diffusion rate. The speed of the bubble collapse (the bubble wall speed) increases to about 90 m/s or less. The shape of a bubble is kept nearly spherical because the amplitude of the nonspherical component of the bubble shape is negligible compared to the instantaneous bubble radius. In other words, a bubble never disintegrates into daughter bubbles during the dissolution. At the final moment of the dissolution, the temperature inside a bubble increases to about 3000 K due to the quasiadiabatic compression. The bubble temperature is higher than 1000 K only for the final 19 ps. However, the Knudsen number is more than 0.2 for this moment, and the error associated with the continuum model should be considerable. In the final 2.3 ns, only nitrogen molecules are present inside a bubble as the solubility of nitrogen is the lowest among the gas species. The radical formation inside a bubble is negligible because the probability of nitrogen dissociation is only on the order of 10-15. The pressure inside a bubble, as well as the liquid pressure at the bubble wall, increases to about 5 GPa at the final moment of dissolution. The pressure is higher than 1 GPa for the final 0.7 ns inside a bubble and for the final 0.6 ns in the liquid at the bubble wall. The liquid temperature at the bubble wall increases to about 360 K from 293 K at the final stage of the complete dissolution.

  20. 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.

  1. Energy efficient for refrigeration and air conditioning

    Directory of Open Access Journals (Sweden)

    Abdeen Mustafa Omer

    2015-03-01

    Full Text Available Over the years, all parts of a commercial refrigerator, such as the compressor, heat exchangers, refrigerant, and packaging, have been improved considerably due to the extensive research and development efforts carried out by academia and industry. However, the achieved and anticipated improvement in conventional refrigeration technology are incremental since this technology is already nearing its fundamentals limit of energy efficiency is described is ‘magnetic refrigeration’ which is an evolving cooling technology. The word ‘green’ designates more than a colour. It is a way of life, one that is becoming more and more common throughout the world. An interesting topic on ‘sustainable technologies for a greener world’ details about what each technology is and how it achieves green goals. Recently, conventional chillers using absorption technology consume energy for hot water generator but absorption chillers carry no energy saving. With the aim of providing a single point solution for this dual purpose application, a product is launched but can provide simultaneous chilling and heating using its vapour absorption technology with 40% saving in heating energy. Using energy efficiency and managing customer energy use has become an integral and valuable exercise. The reason for this is green technology helps to sustain life on earth. This not only applies to humans but to plants, animals and the rest of the ecosystem. Energy prices and consumption will always be on an upward trajectory. In fact, energy costs have steadily risen over last decade and are expected to carry on doing so as consumption grows.

  2. Sea water air conditioning : a cost effective alternative

    Energy Technology Data Exchange (ETDEWEB)

    Elsafty, A.F. [Arab Academy for Science, Technology and Maritime Transport, Alexandria (Egypt). Dept. of Mechanical Engineering, College of Engineering and Technology; Saeid, L. [National Gas Company, Cairo (Egypt). GIS and Design Section

    2009-07-01

    The 2 main types of air conditioning systems are vapor compression systems which are electrically operated, and absorption systems which are heat operated. This paper presented a new air conditioning technique for use in the Middle East. The Sea Water Air Conditioning (SWAC) system uses deep cold ocean and sea water as a renewable energy source to air-condition buildings. A technical and economical assessment was performed to determine the advantages of the SWAC system over conventional vapor compression systems to air-condition hotels and resorts at a new tourists resort in Egypt. Meteorological data for the region was used to estimate the gross cooling load for the hotels using the HVAC Load Explorer program. The major components of the SWAC system were sized and analyzed to the determine its operational performance and to estimate the probable costs. The economic analysis was based on two different methods, notably the net present value (NPV) and the simple pay back method. Three options were investigated in the economic study. The first was the use of a conventional air conditioning system to provide a baseline for the other options being investigated. The second option was the use of deep sea water only, and the third option involved the use of a hybrid system using both a sea water air conditioning system and a conventional chiller in series. The SWAC system was the preferred option for its minimum net present value as well as the short pay back period. The energy savings approached 80 per cent of conventional air-conditioners. It was concluded that in addition to reducing electricity use, the SWAC systems can contribute to a reduction in greenhouse gases. 11 refs., 7 tabs., 6 figs.

  3. Phytomonitoring of air pollution around a thermal power plant

    Science.gov (United States)

    Agrawal, M.; Agrawal, S. B.

    This study was undertaken in order to assess the impact of air pollutants on vegetation around Obra thermal power plant (1550 M W capacity) in the Mirzapur district of Uttar Pradesh. For this purpose, Mangifera indica, Citrus medico and Bouganvillaea spectabilis plants, most common at all sites, were selected as test plants. Five study sites were selected northeast (prevailing wind) of the thermal power plant. A control site was also selected at a distance of 30 km north of Obra. Responses of plants to pollutants in terms of presence of foliar injury symptoms and changes in chlorophyll, ascorbic acid and S content were measured. These changes were correlated with ambient SO 2 and suspended particulate matter (SPM) concentrations and the amount of dust settled on leaf surfaces. The SO 2 and SPM concentrations were quite high in the immediate vicinity of the power plant. There also exists a direct relationship between the concentration of SPM in air and amount of dust deposited on leaf surfaces. Maximum dust deposition was observed on M. indica plants. The levels of foliar injury, chlorophyll and ascorbic acid were found to decrease and that of S increase in plants around the power plant in comparison to those growing at a control site. The magnitude of such changes was maximum in M. indica and minimum in C. medica. A species specific direct relationship between the increase in the amount of S and decrease in chlorophyll content was observed. The study suggests that differential sensitivity of plants to SO 2 may be used in evaluating the air pollution impact around emission sources and M. indica plants can be used as an indicator plant for quantifying biological changes.

  4. Phytomonitoring of air pollution around a thermal power plant

    Energy Technology Data Exchange (ETDEWEB)

    Agrawal, M.; Agrawal, S.B.

    1989-01-01

    This study was undertaken in order to assess the impact of air pollutants on vegetation around Obra thermal power plant (1550 MW capacity) in the Mirzapur district of Uttar Pradesh. For this purpose, Mangifera indica, Citrus medica and Bouganvillaea spectabilis plants, most common at all sites, were selected as test plants. Five study sites were selected northeast (prevailing wind) of the thermal power plant. A control site was also selected at a distance of 30 km north of Obra. Responses of plant to pollutants in terms of presence of foliar injury symptoms and changes in chlorophyll, ascorbic acid and S content were measured. These changes were correlated with ambient SO/sub 2/ and suspended particulate matter (SPM) concentrations and the amount of dust settled on leaf surfaces. The SO/sub 2/ and SPM concentrations were quite high in the immediate vicinity of the power plant. There also exists a direct relationship between the concentration of SPM in air and amount of dust deposited on leaf surfaces. Maximum dust deposition was observed on M. indica plants. The levels of foliar injury, chlorophyll and ascorbic acid were found to decrease and that of S increase in plants around the power plant in comparison to those growing at a control site. The magnitude of such changes was maximum in M. indica and minimum in C. medica. A species specific direct relationship between the increase in the amount of S and decrease in chlorophyll content was observed. The study suggests that differential sensitivity of plants to SO/sub 2/ may be used in evaluating the air pollution impact around emission sources and M. indica plants can be used as an indicator plant for quantifying biological changes. 28 refs., 3 figs., 5 tabs.

  5. 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.

  6. Phase I: the pipeline-gas demonstration plant. Demonstration plant engineering and design. Volume 17. Plant section 2500 - Plant and Instrument Air

    Energy Technology Data Exchange (ETDEWEB)

    None

    1981-05-01

    Contract No. EF-77-C-01-2542 between Conoco Inc. and the US Department of Energy provides for the design, construction, and operation of a demonstration plant capable of processing bituminous caking coals into clean pipeline quality gas. The project is currently in the design phase (Phase I). This phase is scheduled to be completed in June 1981. One of the major efforts of Phase I is the process and project engineering design of the Demonstration Plant. The design has been completed and is being reported in 24 volumes. This is Volume 17 which reports the design of Plant Section 2500 - Plant and Instrument Air. The plant and instrument air system is designed to provide dry, compressed air for a multitude of uses in plant operations and maintenance. A single centrifugal air compressor provides the total plant and instrument air requirements. An air drying system reduces the dew point of the plant and instrument air. Plant Section 2500 is designed to provide air at 100/sup 0/F and 100 psig. Both plant and instrument air are dried to a -40/sup 0/F dew point. Normal plant and instrument air requirements total 1430 standard cubic feet per minute.

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

    Directory of Open Access Journals (Sweden)

    Mohamed M. El-Awad

    2011-03-01

    Full Text Available 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.

  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. [Characteristics of working conditions at metallurgy-related plants].

    Science.gov (United States)

    Egorova, A M

    2008-01-01

    Working conditions at more versus less advanced technology steel plants of the Volgograd Region are analyzed. The working conditions at the less advanced technology plants are referred to as a very high occupational risk. It is necessary to work out measures to lower the poor impact of microclimate, dust, noise, to improve illumination, and to regulate labor at steel plants.

  10. Applicability of sewage heat pump air-conditioning system

    Institute of Scientific and Technical Information of China (English)

    陈金华; 刘猛; 刘勇; 靳鸣; 陈洁

    2009-01-01

    A sewage heat pump system and its application based on a project in Chongqing,China,were discussed. Based on the sewage conditions,a feasibility analysis of the sewage heat pump air conditioning system was conducted. The theoretical and quantitative calculations indicate that sewage flux in the city sewage main pipe in the project can satisfy heat exchange requirements,and taking water from the pipes has relatively small influence on the pipe net in summer and winter. The sewage heat pump air-conditioning system can save 21.5% operating cost in one year,which is energy efficient and environmentally friendly.

  11. Influence of air pollution on cultivated plants

    Energy Technology Data Exchange (ETDEWEB)

    Spierings, F.H.F.G.; Van Raay, A.

    1961-01-01

    Several flower bulbs were fumigated with different concentrations of HF and SO/sub 2/. The most sensitive plants for both gases were: Ixia, Sparaxis and Crocus. Not sensitive for both gases was: Galanthus. Rather sensitive for SO/sub 2/ but not for HF appeared to be: Anemone and Eranthis. In an industrial area fruit trees and also vegetables (endive, carrot) were damaged; the injury of Crataegus hedges and of the weed Solanum nigrum indicated that SO/sub 2/ was probably the cause of the damage. In 1960 an investigation was started to measure light intensities in the field. On seven different localities photometers, which add the light quantities over a certain period, were placed in order to compare the daily light intensities. The aim is to check the light intensity in a horticultural area situated in the neighborhood of a rapidly expanding industrial district. On several locations in The Netherlands gas damage to plants occurs. Periodical investigations are carried out in the field in various places, to detect the nature of the poisoning agents. Particular attention is paid to organic vapors causing gradual discoloration and growth inhibition in ornamental plants. In most cases the damage originated from HF and SO/sub 2/.

  12. Research of Start-Stop of Local Air Conditioning Influence on Temperature Field in Baihetan Hydropower Station Main Plant%白鹤滩水电站局部空调启停对主厂房温度场的影响研究

    Institute of Scientific and Technical Information of China (English)

    刘勇; 龚胜强; 陈林乐; 徐蒯东; 肖益民; 高旖婷

    2016-01-01

    Takes Baihetan hydropower station as an example, describes the similarity theory and model laws based on fluid mechanics. Presents calculation method of modeling similar scale. Obtains the temperature distribution of main plant and optimized design scheme of the hydropower station byexperimental model with different supply air temperature, start-stop control of local air conditioning in busbar floor and bus tunnel. It will be important to guide model experiment and optimization design of air conditioning system in underground large plant.%以白鹤滩水电站为例,介绍了水电站地下厂房通风模型试验的相似理论及模型律,导出模型试验各参数相似比例尺。对水电站模型进行改变送风温度、控制中间层与母线洞的局部空调启停的试验,从而得到主厂房的温度分布和优化设计方案,对地下高大厂房模型试验及其空调系统设计有重要借鉴意义。

  13. 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.

  14. Experimental Investigation of Using Evaporative Air Cooler for Winter Air-Conditioning in Baghdad

    Directory of Open Access Journals (Sweden)

    Zainab Hasson Hassan

    2012-01-01

    Full Text Available This paper presents an efficient methodology to design modified evaporative air-cooler for winter air-conditioning in Baghdad city as well as using it for summer air-conditioning by adding a heating process after the humidification process. Laboratory tests were performed on a direct evaporative cooler (DEC followed by passing the air on hot water through heat exchanger placed in the coolers air duct exit. The tests were conducted on the 2nd of December /2011 when the ambient temperature was 8.1°C and the relative humidity was (68%. The air flow rate is assumed to vary between 0.069 to 0.209 kg/s with constant water flow rate of 0.03 kg/s in the heat exchanger. The performance is reported in terms of effectiveness of DEC, saturation efficiency of DEC, outlet temperature of air and cooling capacity. Heat transfer rate in heat exchanger mode is also estimated. The paper presents the mathematical development of the equations of thermal exchanges through DEC and HE. Prediction of air condition that exits o this system show that the present system could bring the air stream to a comfortable winter zone .

  15. Modeling of air pollution from the power plant ash dumps

    Science.gov (United States)

    Aleksic, Nenad M.; Balać, Nedeljko

    A simple model of air pollution from power plant ash dumps is presented, with emission rates calculated from the Bagnold formula and transport simulated by the ATDL type model. Moisture effects are accounted for by assumption that there is no pollution on rain days. Annual mean daily sedimentation rates, calculated for the area around the 'Nikola Tesla' power plants near Belgrade for 1987, show reasonably good agreement with observations.

  16. Nasal air conditioning in relation to acoustic rhinometry values.

    Science.gov (United States)

    Lindemann, Joerg; Tsakiropoulou, Evangelia; Keck, Tilman; Leiacker, Richard; Wiesmiller, Kerstin M

    2009-01-01

    Changes of nasal dimensions can influence the air-conditioning capacity of the nose because of alterations of airflow patterns. The goal of this study was to evaluate the correlation between intranasal temperature and humidity values and nasal dimensions, assessed by means of acoustic rhinometry. Eighty healthy volunteers (40 men and 40 women; median age, 51 years; range, 20-84 years) were enrolled in the study. In total, 160 nasal cavities were examined. All volunteers underwent a standardized acoustic rhinometry. Additionally, intranasal air temperature and humidity measurements at defined intranasal detection sites within the anterior nasal segment were performed. There was no statistically significant difference between the right and left side of the nose regarding air temperature, absolute humidity, and acoustic rhinometric values. A negative correlation was established between the rhinometric nasal volumes/minimal cross-sectional areas and air temperature and absolute humidity values at the three intranasal detection sites. According to our results, nasal volumes and cross- sectional areas relevantly influence nasal air conditioning. A healthy nasal cavity with smaller volumes and cross-sectional areas seems to present a more effective air-conditioning function than a too "wide" open nose because of changes in airflow patterns. This observation should be considered as a limitation for overly extensive nasal surgery especially of the turbinates.

  17. Intelligent Control System of Textile Mill's Air-conditioning

    Institute of Scientific and Technical Information of China (English)

    WU Fu-zhuan; ZHAO Fang

    2009-01-01

    This paper briefly analyzes the present situation of textile mill's air-conditioning system. Since it is difficult to establish detailed math model to control a textile mill's air-conditioning system because of the influence of various factors such as the differences in seasons, regions, etc., most air-conditioning equipment can not he controlled automatically. This paper suggests utilizing multi-function data acquisition card to collect the data about the temperature and humidity of a workshop, processing the data on a PC, comparing them with the expert database, and then using the 485 serial port expanding module to output the parameters, which are used to control the inverter, so that the purpose of adjusting the temperature and humidity of the workshop is achieved.

  18. Sustainable air-conditioning for the tropical buildings

    Directory of Open Access Journals (Sweden)

    Asrul Mahjuddin Ressang Aminuddin

    2008-12-01

    Full Text Available Tropical climates are thermally uncomfortable and are mostly unhealthy to the occupants of the modern skyscrapers. The temperatures are usually on the hot side coupled with high relative humidity. The population living in the tropics, especially in Malaysia, is getting affluent and can afford air-conditioning their residences and offices. This leads to increased electricity consumption in the buildings. However, switching off the air-conditioning is not an option for the modern buildings as it would affect the health of the people and their productivity. This paper proposes innovative indoor units that will contribute to energy conservation by utilising principles of partial air-conditioning. The outdoor units could be utilised for clothes drying or for providing hot water to the occupants of the building. This will successfully address the issues on sustainable building technologies and techniques. It will lead to considerable savings in energy consumption in buildings in the tropical climate.

  19. AIR CONDITIONING IN MINES IN THE CZECH REPUBLIC AND UKRAINE

    Directory of Open Access Journals (Sweden)

    Pavel Zapletal

    2014-07-01

    Full Text Available The present-day micro-climatic conditions in black coal mines are of such nature that in no mine natural micro-climate conditioning is sufficient any more. The original temperature of rocks grows progressively in dependence on the increasing depth of the extracted seam, or more precisely, on the mining workplace, and this growth is much more significant than previously considered. The temperature of the surrounding rocks, but also high-performance continuous miners and conveyor belt drives heat up airflow, thus worsening microclimatic conditions. This article describes micro-climatic conditions the in Czech Republic and Ukraine and some methods of deep mines air conditioning.

  20. Microbial contamination of the air at the wastewater treatment plant

    Directory of Open Access Journals (Sweden)

    Monika Vítězová

    2012-01-01

    Full Text Available Wastewater treatment plants (WWTPs primarily serve to protect the environment. Their task is to clean waste water from the agglomerations. On the other hand wastewater treatment plants can also negatively affect the environment in their neighbourhood. These include emissions of odour and microorganisms. This article discusses the microbial contamination of the air, called bioaerosols in selected wastewater treatment plant for 18 000 p.e. From results of the work is evident that the largest group of microorganisms in the monitored air were psychrophilic and mesophilic bacteria and microscopic fungi. The number of psychrophilic bacteria ranged from 14 to 12 000 CFU/m3 (colony forming units in 1 m3, the number of mesophilic bacteria varied in the range from 20 to 18 500 CFU/m3 and the fungi from 25 to 32 000 CFU/m3 in the air. The amount of actinomycetes ranged from 1 to 1 030 CFU/m3 and faecal coliform bacteria from 0 to 2 500 CFU/m3. Furthermore, it was confirmed that the highest air contamination was around the activation tank, area for dewatered sludge and around the building of mechanical cleaning, depending on the season. The density of studied microorganisms correlated with air temperature.

  1. Air conditioning: Low-cost autonomous air conditioning systems for bionic buildings; Klimatechnik: Bezahlbare, autarke Klimatisierung von bionischen Gebaeuden

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, H. [ARCADIS, Maastricht (Netherlands); Kutzker, A. [RUBITHERM GmbH, Hamburg (Germany)

    2005-05-01

    Termites in Africa construct buildings that are respectfully referred to as ''cathedrals'' by experts. Millions of insects inhabit these structures that are efficiently air conditioned: While the outside temperatures vary from 10 C at night to 45 C in daytime, the air inside has a constant temperature of 29 C +/- 1 C. The contribution presents a low-cost solution for human buildings. (orig.)

  2. Thermal stratification level of low sidewall air supply with air-conditioning system in large space

    Institute of Scientific and Technical Information of China (English)

    黄晨; 蔡宁; 高雪垒

    2009-01-01

    The thermal stratification level of low sidewall air supply system in large space was defined. Depending on the experiment of low sidewall air supply in summer 2008,the thermal stratification level was studied by simulation. Based on the simulation of experiment condition,the air velocity and vertical temperature distribution in a large space were simulated at different air-outlet velocities,and then the thermal stratification level line was obtained. The simulation results well match with the experimental ones and the average relative error is 3.4%. The thermal stratification level is heightened by increasing the air-outlet velocity with low sidewall air supply mode. It is concluded that when air-outlet velocity is 0.29 m/s,which is the experimental case,a uniform thermal environment in the higher occupied zone and a stable stratification level are formed. When the air-outlet velocity is low,such as 0.05 m/s,the thermal stratification level is too low and the air velocity is too small to meet the human thermal comfort in the occupied zone. So,it would be reasonable that the air-outlet velocity may be designed as 0.31 m/s if the height of the occupied zone is 2 m.

  3. Anthropogenic heating of the urban environment due to air conditioning

    Science.gov (United States)

    Salamanca, F.; Georgescu, M.; Mahalov, A.; Moustaoui, M.; Wang, M.

    2014-05-01

    This article investigates the effect of air conditioning (AC) systems on air temperature and examines their electricity consumption for a semiarid urban environment. We simulate a 10 day extreme heat period over the Phoenix metropolitan area (U.S.) with the Weather Research and Forecasting model coupled to a multilayer building energy scheme. The performance of the modeling system is evaluated against 10 Arizona Meteorological Network weather stations and one weather station maintained by the National Weather Service for air temperature, wind speed, and wind direction. We show that explicit representation of waste heat from air conditioning systems improved the 2 m air temperature correspondence to observations. Waste heat release from AC systems was maximum during the day, but the mean effect was negligible near the surface. However, during the night, heat emitted from AC systems increased the mean 2 m air temperature by more than 1°C for some urban locations. The AC systems modified the thermal stratification of the urban boundary layer, promoting vertical mixing during nighttime hours. The anthropogenic processes examined here (i.e., explicit representation of urban energy consumption processes due to AC systems) require incorporation in future meteorological and climate investigations to improve weather and climate predictability. Our results demonstrate that releasing waste heat into the ambient environment exacerbates the nocturnal urban heat island and increases cooling demands.

  4. Proposal of a Simple Plant Growth System under Microgravity Conditions in Space

    Science.gov (United States)

    Hirai, Hiroaki; Kitaya, Yoshiaki; Hirai, Takehiro; Tsukamoto, Koya; Yamashita, Youichirou

    2012-07-01

    Plant culture in space has multiple functions for human life support such as providing food and purifying air and water. It is also suggested that crew can relieve their stress by watching growing plants and by enjoying fresh vegetable food during staying for several months in the International Space Station. Under such circumstances, it is an utmost importance to develop plant culture equipment that can be handled more easily by crew. This study aims to develop an easy-to-use plant growth system with modification of commercial household plant culture equipment. The item is equipped with a peltier device for cooling air and collecting water vapor in the growth room. The study was conducted to examine the performance of the equipment under microgravity conditions that were created by the parabolic airplane flights. As a result, the temperature of the peltier device was affected under the microgravity conditions due to the absence of heat convection. When an air flow was made with an air circulation fan, the temperature of the peltier device was stable to gravity changes. The water recycling method for an automatic nutrient solution supply system in the closed plant culture equipment under microgravity is proposed. In addition, a high output white LEDs showing a good performance for growing leafy vegetables will be introduced.

  5. [Air pollution biomonitoring with plants and fungi: concepts and uses].

    Science.gov (United States)

    Cuny, D

    2012-07-01

    Air pollution remains a major environmental concern of the French. Since about 30 years, due to evolution and diversification of sources, pollution became more and more complex, constituting a true "cocktail". Today, it is very important to know environmental and health effects of this cocktail. In this context air biomonitoring using plants and fungi can bring a lot of information. Biomonitoring includes four concepts: the use of biomarkers, bioindication biointegration and bioaccumulation. These four concepts are articulated according to the levels of biological organization, what links up biosurveillance on fundamental plan with ecotoxicology. It is a complementary approach of the physicochemical techniques of air pollution measurements. The main objectives of biomonitoring studies are the monitoring of the space and temporal distribution of pollutants effect; the monitoring of local sources; participation in the health risks assessment; the information of people and the help to decision in public policies. Biomonitoring of air quality is a method, which made its proof in numerous domains of application and brings fundamental information on the impacts of the quality of air. Recent evolution of low concerning biggest industries allows us to envisage the increase of air quality biomonitoring with plants and fungi applications in the field of the valuation of environmental and health risks. The recent normalization (French and European) of different methods will also allow the development of uses.

  6. Enabling Smart Air Conditioning by Sensor Development: A Review.

    Science.gov (United States)

    Cheng, Chin-Chi; Lee, Dasheng

    2016-11-30

    The study investigates the development of sensors, in particular the use of thermo-fluidic sensors and occupancy detectors, to achieve smart operation of air conditioning systems. Smart operation refers to the operation of air conditioners by the reinforcement of interaction to achieve both thermal comfort and energy efficiency. Sensors related to thermal comfort include those of temperature, humidity, and pressure and wind velocity anemometers. Improvements in their performance in the past years have been studied by a literature survey. Traditional occupancy detection using passive infra-red (PIR) sensors and novel methodologies using smartphones and wearable sensors are both discussed. Referring to the case studies summarized in this study, air conditioning energy savings are evaluated quantitatively. Results show that energy savings of air conditioners before 2000 was 11%, and 30% after 2000 by the integration of thermo-fluidic sensors and occupancy detectors. By utilizing wearable sensing to detect the human motions, metabolic rates and related information, the energy savings can reach up to 46.3% and keep the minimum change of predicted mean vote (∆PMV→0), which means there is no compromise in thermal comfort. This enables smart air conditioning to compensate for the large variations from person to person in terms of physiological and psychological satisfaction, and find an optimal temperature for everyone in a given space. However, this tendency should be evidenced by more experimental results in the future.

  7. Enabling Smart Air Conditioning by Sensor Development: A Review

    Directory of Open Access Journals (Sweden)

    Chin-Chi Cheng

    2016-11-01

    Full Text Available The study investigates the development of sensors, in particular the use of thermo-fluidic sensors and occupancy detectors, to achieve smart operation of air conditioning systems. Smart operation refers to the operation of air conditioners by the reinforcement of interaction to achieve both thermal comfort and energy efficiency. Sensors related to thermal comfort include those of temperature, humidity, and pressure and wind velocity anemometers. Improvements in their performance in the past years have been studied by a literature survey. Traditional occupancy detection using passive infra-red (PIR sensors and novel methodologies using smartphones and wearable sensors are both discussed. Referring to the case studies summarized in this study, air conditioning energy savings are evaluated quantitatively. Results show that energy savings of air conditioners before 2000 was 11%, and 30% after 2000 by the integration of thermo-fluidic sensors and occupancy detectors. By utilizing wearable sensing to detect the human motions, metabolic rates and related information, the energy savings can reach up to 46.3% and keep the minimum change of predicted mean vote (∆PMV→0, which means there is no compromise in thermal comfort. This enables smart air conditioning to compensate for the large variations from person to person in terms of physiological and psychological satisfaction, and find an optimal temperature for everyone in a given space. However, this tendency should be evidenced by more experimental results in the future.

  8. Need for thermal-storage air-conditioning in Saudi Arabia

    Energy Technology Data Exchange (ETDEWEB)

    Hasnain, Syed Mahmood; Alabbadi, Naif Mohammed [King Abdulaziz City for Science and Technology (KACST), Energy Research Inst., Riyadh (Saudi Arabia)

    2000-04-01

    In Saudi Arabia, the growth of demand for electrical energy in the rapidly expanding towns, cities and industries, far exceeds the growth of the power being made available. Recently the Saudi Consolidated Electric Companies (SCECO) are facing a shortage of electricity during the summer period mainly due to the high consumption of electricity in the air conditioning sector. The incorporation of thermal energy storage (TES) technologies with a conventional air conditioning system is found to be an appropriate solution for energy-demand management. In this paper an introductory overview of thermal storage air conditioning is presented, comparing phase change (e.g. ice) and sensible heat (e.g. chilled water) storage technologies. The pros and cons of each are evaluated. The suitability of TES technology for the Saudi HVAC (heating, ventilating and air conditioning) industry is explored with the benefits to the owner such as: reduced energy consumption; less operation and maintenance costs; and downsizing of the chiller plant and system for new facility; alternative to new chiller installation to cater for increased cooling load; and stored water as a fire protection source. Furthermore, an economic study has been presented to illustrate the feasibility of TES based air conditioning in Saudi Arabia. (Author)

  9. 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.

  10. Ventilation and air-conditioning concept for CNGS underground areas

    CERN Document Server

    Lindroos, J

    2002-01-01

    The aim of the CNGS project is to prove the existence of neutrino oscillation by generating an intense neutrino beam from CERN in the direction of the Gran Sasso laboratory in Italy, where two large neutrino detectors are built to detect the neutrinos. All the components for producing the neutrino beam will be situated in the underground tunnels, service galleries and chambers. The ventilation and air-conditioning systems installed in these underground areas have multiple tasks. Depending on the operating mode and structure to be air-conditioned, the systems are required to provide fresh air, cool the machine, dehumidify areas housing sensible equipment or assure the smoke removal in a case of a fire. This paper presents the technical solutions foreseen to meet these requirements.

  11. Critical condition study of borehole stability during air drilling

    Institute of Scientific and Technical Information of China (English)

    Deng Jingen; Zou Linzhan; Tan Qiang; Yan Wei; Gao Deli; Zhang Hanlin; Yan Xiuliang

    2009-01-01

    The purpose of this paper is to establish the existence of the critical condition of borehole stability during air drilling.Rock Failure Process Analysis Code2D was used to set up a damage model of the borehole excavated in strain-softening rock.Damage evolution around the borehole was studied by tracking acoustic emission.The study indicates that excavation damaged zone (EDZ) is formed around borehole because of stress concentration after the borehole is excavated.There is a critical condition for borehole stability; the borehole will collapse when the critical damage condition is reached.The critical condition of underground excavation exists not only in elastic and ideal plastic material but in strain-softening material as well.The research is helpful to developing an evaluation method of borehole stability during air drilling.

  12. Hospital-acquired infections associated with poor air quality in air-conditioned environments

    Directory of Open Access Journals (Sweden)

    Daniela Pinheiro da Silva

    2014-04-01

    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.

  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. Air quality measurements versus model predictions: a case study for the Sugozu power plant

    Energy Technology Data Exchange (ETDEWEB)

    A. Korur; C. Derinoz; C. Yurteri [ENVY Energy and Environmental Investments Inc., Ankara (Turkey)

    2003-07-01

    Air quality modeling is one of the tools used in Environmental Impact Assessment (EIA) studies in order to predict the potential impacts of atmospheric emissions. The main advantage of air quality modeling is the simulation of the ground-level concentrations under different conditions (i.e., meteorological variations and other pollutant sources in the vicinity). The accuracy of model predictions, on the other hand, depends mainly on the quality of the input data reflecting meteorological and topographical conditions as well as emission sources. In this regard, the model predictions should be supported with monitoring data. In the paper, the predictions of Gaussian air dispersion model (Industrial Source Complex - ISC) for SO{sub 2} and NO{sub 2} carried out in the vicinity of the Sugozu Power Plant on the coast of Turkey are compared with the air quality monitoring results of the same region. 2 refs., 3 figs., 2 tabs.

  15. An Analysis of the Air Conditioning, Refrigerating and Heating Occupation.

    Science.gov (United States)

    Frass, Melvin R.; Krause, Marvin

    The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the air conditioning, refrigerating, and heating occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Six duties are…

  16. Air Conditioning, Heating, and Refrigeration. Competency-Based Curriculum Manual.

    Science.gov (United States)

    Gourley, Frank A., Jr.

    This manual was developed to serve as an aid to administrators and instructors involved with postsecondary air conditioning, heating, and refrigeration programs. The first of six chapters contains general information on program implementation, the curriculum design, facilities and equipment requirements, and textbooks and references. Chapter 2…

  17. 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

  18. 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.

  19. State Skill Standards: Heating, Ventilation, Air Conditioning, and Refrigeration

    Science.gov (United States)

    Ball, Larry; Soukup, Dennis

    2006-01-01

    The Department of Education has undertaken an ambitious effort to develop statewide career and technical education skill standards. The standards in this document are for Heating, Ventilation, Air Conditioning and Refrigeration (HVAC&R) programs and are designed to clearly state what the student should know and be able to do upon completion of…

  20. Heating, Air-Conditioning, and Refrigeration Technician. National Skill Standards.

    Science.gov (United States)

    Vocational Technical Education Consortium of States, Decatur, GA.

    This guide contains information on the knowledge and skills identified by industry as essential to the job performance of heating, air-conditioning, and refrigeration technicians. It is intended to assist training providers in public and private institutions, as well as in industry, to develop and implement training that will provide workers with…

  1. Solar air conditioning researches and demonstrations in China

    Institute of Scientific and Technical Information of China (English)

    Wang Ruzhu

    2009-01-01

    This paper mainly shows the demonstration of solar air conditioning systems in China, which includes LiBr-H2O absorption cooling, silica gel-water adsorption chiller, desiccant cooling and hybrid integrated energy systems for buildings. The match of solar collector types and chiller types have been discussed and suggested.

  2. Modelling and simulation of air-conditioning cycles

    Science.gov (United States)

    Rais, Sandi; Kadono, Yoshinori; Murayama, Katsunori; Minakuchi, Kazuya; Takeuchi, Hisae; Hasegawa, Tatsuya

    2017-02-01

    The heat-pump cycle for air conditioning was investigated both numerically and experimentally by evaluating the coefficient of performance (COP) under Japanese Industrial Standard (JIS B 8619:1999) and ANSI/AHRI standard 750-2007 operating conditions. We used two expansion valve coefficients Cv_{(φ)} = 0.12 for standard operating conditions (Case 1) approaching 1.3 MPa at high pressure and 0.2 MPa at low pressure, and Cv_{(φ)} = 0.06 namely poor operating conditions (Case 2). To improve the performance of the air conditioner, we compared the performance for two outside air temperatures, 35 and 40 °C (Case 3). The simulation and experiment comparison resulted the decreasing of the COP for standard operating condition is equal to 14 %, from 3.47 to 2.95 and a decrease of the cooling capacity is equal to 18 %, from 309.72 to 253.53 W. This result was also occurred in poor operating condition which the COP was superior at 35 °C temperature.

  3. Plant pneumatics: stem air flow is related to embolism - new perspectives on methods in plant hydraulics.

    Science.gov (United States)

    Pereira, Luciano; Bittencourt, Paulo R L; Oliveira, Rafael S; Junior, Mauro B M; Barros, Fernanda V; Ribeiro, Rafael V; Mazzafera, Paulo

    2016-07-01

    Wood contains a large amount of air, even in functional xylem. Air embolisms in the xylem affect water transport and can determine plant growth and survival. Embolisms are usually estimated with laborious hydraulic methods, which can be prone to several artefacts. Here, we describe a new method for estimating embolisms that is based on air flow measurements of entire branches. To calculate the amount of air flowing out of the branch, a vacuum was applied to the cut bases of branches under different water potentials. We first investigated the source of air by determining whether it came from inside or outside the branch. Second, we compared embolism curves according to air flow or hydraulic measurements in 15 vessel- and tracheid-bearing species to test the hypothesis that the air flow is related to embolism. Air flow came almost exclusively from air inside the branch during the 2.5-min measurements and was strongly related to embolism. We propose a new embolism measurement method that is simple, effective, rapid and inexpensive, and that allows several measurements on the same branch, thus opening up new possibilities for studying plant hydraulics.

  4. A strategy for oxygen conditioning at high altitude: comparison with air conditioning.

    Science.gov (United States)

    West, John B

    2015-09-15

    Large numbers of people live or work at high altitude, and many visit to trek or ski. The inevitable hypoxia impairs physical working capacity, and at higher altitudes there is also cognitive impairment. Twenty years ago oxygen enrichment of room air was introduced to reduce the hypoxia, and this is now used in dormitories, hotels, mines, and telescopes. However, recent advances in technology now allow large amounts of oxygen to be obtained from air or cryogenic oxygen sources. As a result it is now feasible to oxygenate large buildings and even institutions such as hospitals. An analogy can be drawn between air conditioning that has improved the living and working conditions of millions of people who live in hot climates and oxygen conditioning that can do the same at high altitude. Oxygen conditioning is similar to air conditioning except that instead of cooling the air, the oxygen concentration is raised, thus reducing the equivalent altitude. Oxygen conditioning on a large scale could transform living and working conditions at high altitude, where it could be valuable in homes, hospitals, schools, dormitories, company headquarters, banks, and legislative settings. Copyright © 2015 the American Physiological Society.

  5. 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.

  6. 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.

  7. AIR POLLUTANTS IN FOOD PROCESSING PLANTS IN IRAN

    Directory of Open Access Journals (Sweden)

    F. Akbarkhanzadeh

    1979-07-01

    Full Text Available Investigations have been carried out on the indoor air pollution in .different workshops of food processing plants in Iran. In order to evaluate the exposure of workers to the three most commonly used indices of air pollution ten food processing plants representing ten groups of food industry with 2.816 workers were selected. Air borne contamination of different origins such cotton seed. Barley, wheat flour salt and different spices sugar an1 beans dust were measured in 237, work places. Here contamination was 8-9 times higher than the proposed T.L. V. for in.3rt dust in 12% of sampling sites Carbon monoxide, measured in 94 sampling site in 69 different work places, which was higher than 50 P .P.M1. in 13% of samples and sulfur-bearing air pollutants determined in 87 different workshop where 103 samples were collected showed the existence of oxides of' sulfur in 34 samples in six industries. The results are presented and the reasons of the existence of these air pollutants are discussed.

  8. 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.

  9. Characterization of process air emissions in automotive production plants.

    Science.gov (United States)

    D'Arcy, J B; Dasch, J M; Gundrum, A B; Rivera, J L; Johnson, J H; Carlson, D H; Sutherland, J W

    2016-01-01

    During manufacturing, particles produced from industrial processes become airborne. These airborne emissions represent a challenge from an industrial hygiene and environmental standpoint. A study was undertaken to characterize the particles associated with a variety of manufacturing processes found in the auto industry. Air particulates were collected in five automotive plants covering ten manufacturing processes in the areas of casting, machining, heat treatment and assembly. Collection procedures provided information on air concentration, size distribution, and chemical composition of the airborne particulate matter for each process and insight into the physical and chemical processes that created those particles.

  10. Nasal air-conditioning after partial turbinectomy: myths versus facts.

    Science.gov (United States)

    Tsakiropoulou, Evangelia; Vital, Victor; Constantinidis, Jannis; Kekes, George

    2015-01-01

    Turbinectomy, although a common procedure, is often accused of having a negative impact in all nasal functions. This study is the first in vivo study that evaluates objectively the effect of partial turbinectomy on nasal air-conditioning capacity. In total, 57 patients with prior partial inferior turbinectomy and 28 healthy controls were examined. Intranasal temperature and humidity values were measured at the level of the head of inferior and middle turbinate. Nasal patency was evaluated by means of acoustic rhinometry. The clinical assessment was completed with nasal endoscopy and the Nasal Obstruction Symptom Evaluation questionnaire for subjective evaluation of nasal patency. Significant changes of temperature were found in both detection sites with 13% reduced heating capacity of the air at the level of the inferior and 19% at the level of the middle turbinate, respectively. No similar results were found for humidity measurements. No correlations were found between air-conditioning values and acoustic rhinometry results for both study groups. Nasal endoscopy revealed normal healing in all patients. No major complications were reported by the patients. Their subjective ratings of nasal obstruction were similar to healthy controls. Partial turbinectomy seems to have a negative impact on intranasal air heating but not to humidification. This effect has no impact on clinical condition and subjective perception of surgical outcome.

  11. Design and Implementation of Air Conditioning System in Operating Room

    Directory of Open Access Journals (Sweden)

    Htet Htet Aung

    2014-10-01

    Full Text Available The system is air conditioning system in operating room. The main objective of the system was implemented to provide air balance and temperature necessary conditions and to control airflow system for ventilation units in operating room. The operation room can be controlled with fuzzy expert system and describes the desired outputs. Input parameters such as temperature, humidity, oxygen and particle are used and output parameters are chosen as air conditioning motor speed and exhaust motor speed. Input parameters of the system are taken into account optimal conditions based on oxygen as medium and other parameters are chosen minimum condition for operating room. The airflow control system is determined the two components: the airflow block and the thermal block for ventilation units in operating room. The mathematical modeling of each such system based on a computational procedure and to combine them together in an efficient manner. Whether it supports to the most suitable control for the system prototype was determined by simulating the operation with varying the number of personnel and duration of time. Finally, according to the combination of temperature and airflow regulations with PI controller, the results of simulation of the entire ventilation unit control system is obtained.

  12. A survey of energy efficient strategies for effective air conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Al-Rabghi, O.M.; Akyurt, M.M. [King Abdulaziz University, Jeddah (Saudi Arabia). Dept. of Mechanical Engineering

    2004-07-01

    Several methods are presented for lowering the energy consumed during air conditioning of buildings. Some of these strategies can be implemented during the design stage; others can be used to retrofit existing AC systems; and still others can be applied with hardly any changes on existing equipment. The methods that are discussed include heat recovery and utilization, absorption refrigeration systems, thermal cool storage, liquid (refrigerant) pressure amplification, reprogramming of the AC control systems, economical methods of removal of moisture from the air and initiation of awareness programs for the conservation of A/C energy. (author)

  13. 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.)

  14. 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.

  15. Problems in creation of modern air inlet filters of power gas turbine plants in Russia and methods of their solving

    Science.gov (United States)

    Mikhaylov, V. E.; Khomenok, L. A.; Sherapov, V. V.

    2016-08-01

    The main problems in creation and operation of modern air inlet paths of gas turbine plants installed as part of combined-cycle plants in Russia are presented. It is noted that design features of air inlet filters shall be formed at the stage of the technical assignment not only considering the requirements of gas turbine plant manufacturer but also climatic conditions, local atmospheric air dustiness, and a number of other factors. The recommendations on completing of filtration system for air inlet filter of power gas turbine plants depending on the facility location are given, specific defects in design and experience in operation of imported air inlet paths are analyzed, and influence of cycle air preparation quality for gas turbine plant on value of operating expenses and cost of repair works is noted. Air treatment equipment of various manufacturers, influence of aerodynamic characteristics on operation of air inlet filters, features of filtration system operation, anti-icing system, weather canopies, and other elements of air inlet paths are considered. It is shown that nonuniformity of air flow velocity fields in clean air chamber has a negative effect on capacity and aerodynamic resistance of air inlet filter. Besides, the necessity in installation of a sufficient number of differential pressure transmitters allowing controlling state of each treatment stage not being limited to one measurement of total differential pressure in the filtration system is noted in the article. According to the results of the analysis trends and methods for modernization of available equipment for air inlet path, the importance of creation and implementation of new technologies for manufacturing of filtering elements on sites of Russia within the limits of import substitution are given, and measures on reliability improvement and energy efficiency for air inlet filter are considered.

  16. Phytoremediation of particulate matter from indoor air by Chlorophytum comosum L. plants

    OpenAIRE

    Gawrońska, H.; Bakera, B.

    2014-01-01

    Higher plants, including spider plants, are able to take up and degrade/detoxify various pollutants in the air. Although nearly 120 plant species have been tested for indoor air phytoremediation, to the best of the authors’ knowledge, data on particulate matter (PM) phytoremediation from indoor air are not yet available in literature. This work determined the ability of spider plants to take up PM, one of the most harmful pollutants to man, in the indoor air of five rooms housing different ac...

  17. Solar desiccant air-conditioning. Practical experience regarding operation and performance

    Energy Technology Data Exchange (ETDEWEB)

    Haller, A.; Trinkl, C.; Wittmann, R.; Zoerner, W. [Ingolstadt Univ. of Applied Sciences (Germany). Kompetenzzentrum Solartechnik; Hanby, V. [De Montfort Univ., Leicester (GB). Inst. of Energy and Sustainable Development (IESD)

    2007-07-01

    The Kompetenzzentrum Solartechnik of Ingolstadt University of Applied Sciences (Centre of Excellence for Solar Engineering) investigates the renewable-only based HVAC system of a multipurpose building. The 10.000 m{sup 2} gross floor area building is part of the biggest logistic-centre in the region serving the AUDI automobile production facilities. On the one hand, the investigation is supposed to demonstrate the potential of solar-assisted cooling, on the other hand, the monitoring, financed by the Bavarian Ministry of Environmental Affairs, focuses on the total energy balance of the building and the various innovative building technologies. Next to a ground source heat pump plant for base-load heating and cooling, the building is equipped with two arrays of solar-thermal flat-plate collectors (100 m{sup 2} of Conergy, Germany, and 180 m{sup 2} of Solahart, Australia) and a desiccant air-conditioning system (DEC, WOLF Anlagen-Technik, Germany). This consists of two plants with an air flow of 8.000 m{sup 3}/h and a nominal cooling capacity of 42 kW each. One of the two plants is monitored. The plant itself is considered a black box in a first approach, i.e. all incoming and outgoing energy flows and the air condition are measured. Apart from the investigation of the performance of the solar-assisted air-conditioning system, the feasibility of DEC-operation using flat-plate collectors available on the market is investigated. (orig.)

  18. 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

  19. Pollution resistance assessment of existing landscape plants on Beijing streets based on air pollution tolerance index method.

    Science.gov (United States)

    Zhang, Peng-Qian; Liu, Yan-Ju; Chen, Xing; Yang, Zheng; Zhu, Ming-Hao; Li, Yi-Ping

    2016-10-01

    Various plant species of green belt in urban traffic area help to reduce air pollution and beautify the city environment. Those plant species growing healthily under long-term atmospheric pollution environment are considered to be resilient. This study aims to identify plant species that are more tolerant to air pollution from traffic and to give recommendations for future green belt development in urban areas. Leaf samples of 47 plant species were collected from two heavy traffic roadside sites and one suburban site in Beijing during summer 2014. Four parameters in leaves were separately measured including relative water content (RWC), total chlorophyll content (TCH), leaf-extract pH (pH), and ascorbic acid (AA). The air pollution tolerance index (APTI) method was adopted to assess plants' resistance ability based on the above four parameters. The tolerant levels of plant species were classified using two methods, one by comparing the APTI value of individual plant to the average of all species and another by using fixed APTI values as standards. Tolerant species were then selected based on combination results from both methods. The results showed that different tolerance orders of species has been found at the three sampling sites due to varied air pollution and other environmental conditions. In general, plant species Magnolia denudata, Diospyros kaki, Ailanthus altissima, Fraxinus chinensis and Rosa chinensis were identified as tolerant species to air pollution environment and recommend to be planted at various location of the city, especially at heavy traffic roadside.

  20. Development of nanolubricant automotive air conditioning (AAC test rig

    Directory of Open Access Journals (Sweden)

    Redhwan A.A.M.

    2017-01-01

    Full Text Available Nanolubricant been introduced in compressor might improve the performance of automotive air conditioning system. Prior testing of the nanolubricant enhancement performance, an automotive air conditioning (AAC system test rig base on compact car has to be developed; therefore this paper presented the development process of AAC test rig. There are 15 thermocouples, 2 pressure gauges and power analyzer were assembled on the system in order to analyse its performance. The experiment was conducted with four different charged of refrigerant. The charging was based on initial weight charged. At each quantity of refrigerant charge, performance of the AAC system was evaluated by determining three important parameters which is cooling capacity, compressor work and coefficient of performance (COP. The maximum average COP is achieved at 900 RPM is 7.07. The average and maximum COP enhancement of 7.07 % and 13.34 % were achieved by applying SiO2 nanolubricant inside the compressor.

  1. Working fluid concentration measurement in solar air conditioning systems

    Energy Technology Data Exchange (ETDEWEB)

    Romero, R.J.; Basurto-Pensado, M.A. [Centro de Investigacion en Ingenieria y Ciencias Aplicadas, Universidad Autonoma del Estado de Morelos, Av. Universidad 1001. Col. Chamilpa, C.P. 62210, Cuernavaca, Morelos (Mexico); Jimenez-Heredia, A.H.; Sanchez-Mondragon, J.J. [Departamento de Optica, Instituto Nacional de Astrofisica Optica y Electronica, Luis Enrique Erro No. 1, Tonantzintla, Apartado Postal 51 y 216, C.P. 72000, Puebla (Mexico)

    2006-02-15

    In order to evaluate on-line corrosive electrolyte concentration in solar air conditioning systems, an optical technique to determine the concentration is being proposed. With this optical sensing method, it is possible to measure the percentage concentration of the aqueous corrosive lithium bromide solution at temperatures ranging from 25{sup o}C to 70{sup o}C and a maximum concentration of 60%. The measurement system is based on the refractive index of the solution and the data correlation, at several temperature and concentration values. The results of this work present a direct method for concentration measurement of corrosive liquids and also show the correlation among the three parameters: refractive index, temperature and weight concentration. This correlation can be used to develop the optical device for solar air conditioning systems to control and improve efficiency. (author)

  2. [Air conditioning units and warm air blankets in the operating room].

    Science.gov (United States)

    Kerwat, Klaus; Piechowiak, Karolin; Wulf, Hinnerk

    2013-01-01

    Nowadays almost all operating rooms are equipped with air conditioning (AC units). Their main purpose is climatization, like ventilation, moisturizing, cooling and also the warming of the room in large buildings. In operating rooms they have an additional function in the prevention of infections, especially the avoidance of postoperative wound infections. This is achieved by special filtration systems and by the creation of specific air currents. Since hypothermia is known to be an unambiguous factor for the development of postoperative wound infections, patients are often actively warmed intraoperatively using warm air blankets (forced-air warming units). In such cases it is frequently discussed whether such warm air blankets affect the performance of AC units by changing the air currents or whether, in contrast, have exactly the opposite effect. However, it has been demonstrated in numerous studies that warm air blankets do not have any relevant effect on the functioning of AC units. Also there are no indications that their use increases the rate of postoperative wound infections. By preventing the patient from experiencing hypothermia, the rate of postoperative wound infections can even be decreased thereby. © Georg Thieme Verlag Stuttgart · New York.

  3. Solar air-conditioning-active, hybrid and passive

    Energy Technology Data Exchange (ETDEWEB)

    Yellott, J. I.

    1981-04-01

    After a discussion of summer air conditioning requirements in the United States, active, hybrid, and passive cooling systems are defined. Active processes and systems include absorption, Rankine cycle, and a small variety of miscellaneous systems. The hybrid solar cooling and dehumidification technology of desiccation is covered as well as evaporative cooling. The passive solar cooling processes covered include convective, radiative and evaporative cooling. Federal and state involvement in solar cooling is then discussed. (LEW)

  4. HVAC; Heating, Ventilation, Air Conditioning - Aerosol Duct Sealant

    Science.gov (United States)

    2016-09-01

    Approved for public release: distribution unlimited TDS-NAVFAC-EXWC-PW-1603 Sep 2016 HVAC ; Heating, Ventilation, Air Conditioning - Aerosol...energy consumption, depending on the HVAC system type and the location of the ducts that were sealed. The cost effectiveness of the technology is...Although several studies have been done on the effectiveness of sealing leaky HVAC ductwork with aerosol duct sealant, few studies have been done on

  5. Control Techniques in Heating, Ventilating and Air Conditioning Systems

    OpenAIRE

    H. Mirinejad; Sadati, S.H.; M Ghasemian; H. Torab

    2008-01-01

    Problem statement: Heating, Ventilating and Air Conditioning (HVAC) systems are among the main installations in residential, commercial and industrial buildings. The purpose of the HVAC systems is normally to provide a comfortable environment in terms of temperature, humidity and other environmental parameters for the occupants as well as to save energy. Achieving these objectives requires a suitable control system design. Approach: In this overview, thermal comfort level and ISO comfort fiel...

  6. Microbiological air quality at municipal waste sorting plant

    Directory of Open Access Journals (Sweden)

    Bulski Karol

    2016-12-01

    Full Text Available Municipal waste plants can be a source of biological contamination of the environment, depending on the method of operation and the type of collected waste. The aim of this study was the quantitative characteristics of airborne microorganisms at the Barycz municipal waste sorting plant in Cracow. Bioaerosol measurements of indoor and outdoor air of the municipal waste sorting plant were performed during the summer season using a six-stage Andersen cascade impactor. The highest concentration of bacterial and fungal aerosol was observed in the medium fraction sorting room (129.02×103 cfu·m-3 and 116.21×103 cfu·m-3, respectively. There were statistically significant differences in the concentrations of bacterial and fungal aerosol between indoor and outdoor air. The calculations showed a significant correlation between the concentration of bioaerosol and particulate matter. Based on the analysis of bioaerosol particle size distribution, it was found that the concentration of bacteria and fungi has a maximum value in the diameter range 3.3-7.0 μm. The study confirmed that the municipal waste sorting plants can be causing exposure to microbiological agents.

  7. Persistence of initial conditions in continental scale air quality ...

    Science.gov (United States)

    This study investigates the effect of initial conditions (IC) for pollutant concentrations in the atmosphere and soil on simulated air quality for two continental-scale Community Multiscale Air Quality (CMAQ) model applications. One of these applications was performed for springtime and the second for summertime. Results show that a spin-up period of ten days commonly used in regional-scale applications may not be sufficient to reduce the effects of initial conditions to less than 1% of seasonally-averaged surface ozone concentrations everywhere while 20 days were found to be sufficient for the entire domain for the spring case and almost the entire domain for the summer case. For the summer case, differences were found to persist longer aloft due to circulation of air masses and even a spin-up period of 30 days was not sufficient to reduce the effects of ICs to less than 1% of seasonally-averaged layer 34 ozone concentrations over the southwestern portion of the modeling domain. Analysis of the effect of soil initial conditions for the CMAQ bidirectional NH3 exchange model shows that during springtime they can have an important effect on simulated inorganic aerosols concentrations for time periods of one month or longer. The effects are less pronounced during other seasons. The results, while specific to the modeling domain and time periods simulated here, suggest that modeling protocols need to be scrutinized for a given application and that it cannot be assum

  8. High Technology Centrifugal Compressor for Commercial Air Conditioning Systems

    Energy Technology Data Exchange (ETDEWEB)

    Ruckes, John

    2006-04-15

    R&D Dynamics, Bloomfield, CT in partnership with the State of Connecticut has been developing a high technology, oil-free, energy-efficient centrifugal compressor called CENVA for commercial air conditioning systems under a program funded by the US Department of Energy. The CENVA compressor applies the foil bearing technology used in all modern aircraft, civil and military, air conditioning systems. The CENVA compressor will enhance the efficiency of water and air cooled chillers, packaged roof top units, and other air conditioning systems by providing an 18% reduction in energy consumption in the unit capacity range of 25 to 350 tons of refrigeration The technical approach for CENVA involved the design and development of a high-speed, oil-free foil gas bearing-supported two-stage centrifugal compressor, CENVA encompassed the following high technologies, which are not currently utilized in commercial air conditioning systems: Foil gas bearings operating in HFC-134a; Efficient centrifugal impellers and diffusers; High speed motors and drives; and System integration of above technologies. Extensive design, development and testing efforts were carried out. Significant accomplishments achieved under this program are: (1) A total of 26 builds and over 200 tests were successfully completed with successively improved designs; (2) Use of foil gas bearings in refrigerant R134a was successfully proven; (3) A high speed, high power permanent magnet motor was developed; (4) An encoder was used for signal feedback between motor and controller. Due to temperature limitations of the encoder, the compressor could not operate at higher speed and in turn at higher pressure. In order to alleviate this problem a unique sensorless controller was developed; (5) This controller has successfully been tested as stand alone; however, it has not yet been integrated and tested as a system; (6) The compressor successfully operated at water cooled condensing temperatures Due to temperature

  9. Metro tunnels enable geothermal air-conditioning. Geothermal plants can be integrated into new tunnel structures in inner cities; Klimatisieren mit Erdwaerme aus U-Bahn-Tunneln. Geothermische Anlagen lassen sich in neue Tunnelbauwerke in Innenstaedten integrieren

    Energy Technology Data Exchange (ETDEWEB)

    Geimer, Christina

    2013-10-01

    When constructing new underground metro lines it is possible to integrate geothermal plants with few additional costs. That provides an excellent opportunity to use this renewable energy source in cities with densely built underground infrastructures. A test plant is in operation on Metro Line 6 at Stuttgart's Fasanenhof underground station. Scientists at the University of Stuttgart are investigating the effects that the geothermal activation of the tunnel is having on the subsurface.

  10. Temperature and Humidity Control in Air-Conditioned Buildings with lower Energy Demand and increased Indoor Air Quality

    DEFF Research Database (Denmark)

    Paul, Joachim; Martos, E. T.

    2003-01-01

    %. For indoor air temperature and humidity control, the use of an ice slurry (´Binary Ice´)was compared to conventional chilled water. The use of Binary Ice instead of chilled water makes the air handling and air distribution installation much simpler, recirculation of air becomes obsolete, and a higher portion....... Binary Ice as secondary refrigerant for air-conditioning purposes is an economical and technically feasible solution in any climate. Whatever chilled water can do in an air-conditioning installation ? Binary Ice can do it better....... of ambient air can be supplied, thus improving the indoor air quality still further. Reheating of air is not necessary when using Binary Ice. The introduction of chilled air into a room requires a different type of air outlet, however. When using Binary Ice, energy savings are high for climates with low...

  11. Solar energy contribution to the energy demand for air conditioning system in an office building under Tripoli climate conditions

    Directory of Open Access Journals (Sweden)

    Musbah Mohamed H.

    2014-01-01

    Full Text Available The feasibility of solar assisted air conditioning in an office building under Tripoli weather conditions is investigated in this paper. A single-effect lithium bromide absorption cycle powered by means of flat-plate solar collectors was modeled in order to predict the potential of the solar energy share. The cooling load profile was generated by using an detailed hourly based program and Typical meteorological year for Tripoli. System performance and solar energy fraction were calculated by varying two major parameters (collector’s slope angle and collector area. The maximum solar fraction of 48% was obtained by means of 1400 m2 of collector surface area. Analysis of results showed that, besides the collector surface area, the main factors affecting the solar fraction were the local weather conditions (intensity of incident solar radiation and the time of day when the plant was operated.

  12. The new air conditioning wind tunnel at Vienna; Der neue Klima-Wind-Kanal in Wien

    Energy Technology Data Exchange (ETDEWEB)

    Haller, G. [Oesterreichisches Forschungs- und Pruefzentrum Arsenal Ges.m.b.H., Wien (Austria)

    2003-07-01

    The world's only air conditioning wind tunnel for railway vehicles is located in Vienna (Wien Arsenal). For more than 40 years, air conditioning tests, functional tests and reliability tests have been carried out here on components, aggregates, and systems. Applications range from research and development to type testing and certification. In order to cope with future requirements, a new plant is currently being constructed (Pauker-Gruende), also in Vienna. The contribution describes current and future R + D goals in the field of air conditioning simulations for public transportation. On this basis, the specifications on the new air conditioning wind tunnel will be specified. The project and its functionalities are presented. [German] Im weltweit einzigen Klima-Wind-Kanal fuer Schienenfahrzeuge in Wien Arsenal werden seit mehr als 40 Jahren klimatechnische Untersuchungen, Funktions- und Zuverlaessigkeitstests an Komponenten, Aggregaten und am Gesamtsystem durchgefuehrt. Das Dienstleistungsspektrum reicht dabei von der Forschung ueber die Entwicklungsunterstuetzung bis hin zur Typenpruefung und Zertifizierung. Um den technischen Erfordernissen der Zukunft und der notwendigen Flexibilitaetsausweitung zu entsprechen, wird derzeit diese Anlage auf den Pauker-Gruenden in Wien neu errichtet. Der Beitrag beschreibt die derzeitigen und zukuenftigen Forschungs- und Entwicklungsschwerpunkte auf dem Gebiet der Klimasimulation oeffentlicher Verkehrsmittel. Daraus ergeben sich spezielle technische Anforderungen an einen neuen Klima-Wind-Kanal, die unter Einbeziehung der Erfahrungen mit der bestehenden Anlage naeher erlaeutert werden. Abschliessend werden das Ausfuehrungsprojekt selbst und deren erweiterte Moeglichkeiten dargestellt. (orig.)

  13. 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.

  14. Effect of Intake Air Filter Condition on Vehicle Fuel Economy

    Energy Technology Data Exchange (ETDEWEB)

    Norman, Kevin M [ORNL; Huff, Shean P [ORNL; West, Brian H [ORNL

    2009-02-01

    The U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy and the U.S. Environmental Protection Agency (EPA) jointly maintain a fuel economy website (www.fueleconomy.gov), which helps fulfill their responsibility under the Energy Policy Act of 1992 to provide accurate fuel economy information [in miles per gallon (mpg)] to consumers. The site provides information on EPA fuel economy ratings for passenger cars and light trucks from 1985 to the present and other relevant information related to energy use such as alternative fuels and driving and vehicle maintenance tips. In recent years, fluctuations in the price of crude oil and corresponding fluctuations in the price of gasoline and diesel fuels have renewed interest in vehicle fuel economy in the United States. (User sessions on the fuel economy website exceeded 20 million in 2008 compared to less than 5 million in 2004 and less than 1 million in 2001.) As a result of this renewed interest and the age of some of the references cited in the tips section of the website, DOE authorized the Oak Ridge National Laboratory (ORNL) Fuels, Engines, and Emissions Research Center (FEERC) to initiate studies to validate and improve these tips. This report documents a study aimed specifically at the effect of engine air filter condition on fuel economy. The goal of this study was to explore the effects of a clogged air filter on the fuel economy of vehicles operating over prescribed test cycles. Three newer vehicles (a 2007 Buick Lucerne, a 2006 Dodge Charger, and a 2003 Toyota Camry) and an older carbureted vehicle were tested. Results show that clogging the air filter has no significant effect on the fuel economy of the newer vehicles (all fuel injected with closed-loop control and one equipped with MDS). The engine control systems were able to maintain the desired AFR regardless of intake restrictions, and therefore fuel consumption was not increased. The carbureted engine did show a decrease in

  15. Membrane-based air conditioning. Decentral desiccant cooling; Membranbasierte Raumklimatisierung. Dezentrale sorptionsgestuetzte Klimatisierung

    Energy Technology Data Exchange (ETDEWEB)

    Rosenbaum, Hannes [Institut fuer Luft- und Kaeltetechnik gGmbH, Dresden (Germany)

    2012-04-15

    Semipermeable membranes have a considerable potential use in air conditioning systems due to their properties. As water resistant but water vapor permeable functional separation layers, they allow desiccant air-conditioning processes in decentral air conditioning systems and a condensate-free air dehumidification at cooling ceiling elements. (orig.)

  16. Auditing the European room air-conditioning systems and potential energy savings

    Energy Technology Data Exchange (ETDEWEB)

    Bory, Daniela; Adnot, Jerome; Greco, Carmelo; Marchio, Dominique [Ecole des Mines de Paris, Center for Energy and Processes (France)

    2007-07-01

    Nowadays, the European Community promotes the energy improvement of the air-conditioning (AC) systems through the compulsory inspection of these facilities in the frame of the Energy Performance of Buildings Directive [EPBD, 2002]. Inspection itself is just a motivating mean for the AC actors to improve the energy efficiency of the systems and reduce energy. Therefore, the aim of the inspection is to follow periodically the correct management of the facility through a quick visit of the plant and a study of the available documentation while the aim of the audit is the research of best efficiency improvements which requires further investigations to evaluate and quantify the savings. Audit differs from the common maintenance activities of the facilities, the aim of which is limited to guarantee the basic operation of the plant. There is an overall lack of methodologies specific for air-conditioning and the improvements proposed are seldom proven with scientific rigour. For room air conditioning systems, the impacts of defect during operation due to ageing and neglected maintenance are considered: fouled condenser, charge leaks, compressor performances reduced, fans degradation, filter fouling and additional pressure drop in liquid line are explored. The over consumption due to these defects is evaluated for different building types and French climates. The results allow to define simple methods that can be used by the auditors to estimate the energy savings due to the correction of the defects.

  17. Persistence of initial conditions in continental scale air quality simulations

    Science.gov (United States)

    Hogrefe, Christian; Roselle, Shawn J.; Bash, Jesse O.

    2017-07-01

    This study investigates the effect of initial conditions (IC) for pollutant concentrations in the atmosphere and soil on simulated air quality for two continental-scale Community Multiscale Air Quality (CMAQ) model applications. One of these applications was performed for springtime and the second for summertime. Results show that a spin-up period of ten days commonly used in regional-scale applications may not be sufficient to reduce the effects of initial conditions to less than 1% of seasonally-averaged surface ozone concentrations everywhere while 20 days were found to be sufficient for the entire domain for the spring case and almost the entire domain for the summer case. For the summer case, differences were found to persist longer aloft due to circulation of air masses and even a spin-up period of 30 days was not sufficient to reduce the effects of ICs to less than 1% of seasonally-averaged layer 34 ozone concentrations over the southwestern portion of the modeling domain. Analysis of the effect of soil initial conditions for the CMAQ bidirectional NH3 exchange model shows that during springtime they can have an important effect on simulated inorganic aerosols concentrations for time periods of one month or longer. The effects are less pronounced during other seasons. The results, while specific to the modeling domain and time periods simulated here, suggest that modeling protocols need to be scrutinized for a given application and that it cannot be assumed that commonly-used spin-up periods are necessarily sufficient to reduce the effects of initial conditions on model results to an acceptable level. What constitutes an acceptable level of difference cannot be generalized and will depend on the particular application, time period and species of interest. Moreover, as the application of air quality models is being expanded to cover larger geographical domains and as these models are increasingly being coupled with other modeling systems to better represent

  18. 新疆某电厂办公区半集中式蒸发冷却空调系统的工程应用分析%In A Power Plant in Xinjiang Office Semi-central Evaporative Air-conditioning System Application Analysis

    Institute of Scientific and Technical Information of China (English)

    王伟; 黄翔; 孙铁柱; 吴生; 于优城; 唐永戬; 杨晓弟

    2012-01-01

    介绍了半集中式蒸发冷却空调系统的设计过程,对应用在新疆某电厂办公区的半集中式蒸发冷却空调系统进行详细的测试分析.测试结果表明:三级蒸发冷却新风机组将室外干球温度为35℃,湿球温度为19.8℃的空气,处理至干球温度为15℃低温空气送入室内.蒸发冷却高温冷水机组制取干球温度为17℃的冷水,完全满足干式风机盘管的要求.整个半集中式蒸发冷却串联系统中,风机盘管回水在高温表冷器中可以将室外空气的温度降低7℃以上,形成了冷量的多重利用.同时希望通过这样的实例设计过程分析为相关的设计人员提供一定的参考.%The design process of semi-central evaporative air conditioning system was briefly introduced, the application of a certain power plant in xinjiang office semi-central evaporative air conditioning system for detailed analysis of the test. Test results show that; three new air handling units to evaporative cooling outdoor dry bulb temperature of 35℃ , wet bulb temperature of 19. 8℃, air treatment to dry bulb temperature is 15℃ low temperature air into the room. Evaporative cooling high-temperature water chiller system to take dry-bulb temperature of 17℃ cold water, fully meet the requirements of dry-type fan coil. Evaporative cooling throughout the series semi-centralized system, fan coil return water at high temperatures can be cooler outdoor air temperature 7℃ lower than the formation of a cooling capacity of multiple use. Also hope that through this analysis of the relevant instance of the design process designers to provide a reference.

  19. The Predictive Control Method of VAV Air Conditioning System

    Directory of Open Access Journals (Sweden)

    Jiejia LI

    2013-09-01

    Full Text Available Aiming at the characteristics which variable air volume air conditioning system is multi-variable, nonlinear and uncertain system, normal fuzzy neural network is hard to meet the requirements which dynamic control of multi-variable. In this paper, we put forward a recursive neural network predictive control strategy based on wavelet neural network model. Through recursive wavelet neural network predictor on line established controlled object’s mathematical model, and using Elman neural network controller on line corrected information we get, thus to improve control effect. The simulation results show that recursive wavelet neural network predictive control has stronger robustness and adaptive ability, high control precision, better and reliable control effect and other advantages.

  20. Air pollution impedes plant-to-plant communication, but what is the signal?

    Science.gov (United States)

    Blande, James D; Li, Tao; Holopainen, Jarmo K

    2011-07-01

    Since the first reports that undamaged plants gain defensive benefits following exposure to damaged neighbors, the idea that plants may signal to each other has attracted much interest. There has also been substantial debate concerning the ecological significance of the process and the evolutionary drivers. Part of this debate has centered on the distance over which signaling between plants occurs in nature. In a recent study we showed that an ozone concentration of 80 ppb, commonly encountered in nature, significantly reduces the distance over which plant-plant signaling occurs in lima bean. We went on to show that degradation of herbivore-induced plant volatiles by ozone is the likely mechanism for this. The key question remaining from our work was that if ozone is degrading the signal in transit between plants, which chemicals are responsible for transmitting the signal in purer air? Here we present the results of a small scale experiment testing the role of the two most significant herbivore-induced terpenes and discuss our results in terms of other reported functions for these chemicals in plant-plant signaling.

  1. Rational utilization of energy applications in the facility management. Energy efficient system technologies of the ventilation technology, air conditioning technology, refrigeration technology and lighting technology. Plant concepts, applications and practical tips; Rationelle Energieanwendungen in der Gebaeudetechnik. Energieeffiziente Systemtechnologien der Raumluft-, Klima-, Kaelte-, und Beleuchtungstechnik. Anlagenkonzepte, Anwendungen, Praxistipps

    Energy Technology Data Exchange (ETDEWEB)

    Theiss, Eric

    2012-11-01

    Due to increasing energy prices and increasingly scarce resources, existing energy-intensive systems of the ventilation technology, air conditioning technology, refrigeration technology as well as lighting technology have to be reconsidered. Innovative approaches have to be developed. Under this aspect, the author of the book under consideration describes functional principles and variants of utilization as well as innovations and prototypes in this area. The optimisation of the energy efficiency and the increase of the user comfort are illustrated by means of the building automation. With respect to the actual regulations, the characteristic parameters are examined. Economic feasibility studies are performed. By way of illustration, possible system integrations are described on the basis of example plants and object descriptions. The author of this book also presents a glossary and the most important contact addresses. The book under consideration is an ideal advisor for architects, building owners, investors, specialist engineers, energy consultants and students.

  2. [Negative air ions generated by plants upon pulsed electric field stimulation applied to soil].

    Science.gov (United States)

    Wu, Ren-ye; Deng, Chuan-yuan; Yang, Zhi-jian; Weng, Hai-yong; Zhu, Tie-jun-rong; Zheng, Jin-gui

    2015-02-01

    This paper investigated the capacity of plants (Schlumbergera truncata, Aloe vera var. chinensis, Chlorophytum comosum, Schlumbergera bridgesii, Gymnocalycium mihanovichii var. friedrichii, Aspidistra elatior, Cymbidium kanran, Echinocactus grusonii, Agave americana var. marginata, Asparagus setaceus) to generate negative air ions (NAI) under pulsed electric field stimulation. The results showed that single plant generated low amounts of NAI in natural condition. The capacity of C. comosum and G. mihanovichii var. friedrichii generated most NAI among the above ten species, with a daily average of 43 ion · cm(-3). The least one was A. americana var. marginata with the value of 19 ion · cm(-3). When proper pulsed electric field stimulation was applied to soil, the NAI of ten plant species were greatly improved. The effect of pulsed electric field u3 (average voltage over the pulse period was 2.0 x 10(4) V, pulse frequency was 1 Hz, and pulse duration was 50 ms) was the greatest. The mean NAI concentration of C. kanran was the highest 1454967 ion · cm(-3), which was 48498.9 times as much as that in natural condition. The lowest one was S. truncata with the value of 34567 ion · cm(-3), which was 843.1 times as much as that in natural condition. The capacity of the same plants to generate negative air ion varied extremely under different intensity pulsed electric fields.

  3. The new solar energy air conditioning system of CERIT (Pordenone, Italy). First experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.; Casasola, L. (Bari Univ. (Italy). Ist. di Fisica Tecnica ed Impianti Termotecnici; CERIT SpA, Pordenone (Italy))

    For air conditioning in the CERIT (Regional Center for Technological Research) building of Pordenone (Italy), a solar plant was installed, with a surface area of 430 square meters of evacuated-tube collectors, a reflecting surface of the same area, and an absorption refrigerating system. Furthermore, this plant was equipped with a 43 cubic meter heat storage unit at the temperature of 80-90 degrees C and also a 150 cubic meter cold storage unit. The choice of the collectors was made after a series of tests on various models existing on the market. A careful calculation was carried out on the advantages of flat reflectors. An estimate, reflecting results after one year of operation, of the plant's performance was developed.

  4. [Influence endophytic bacteria to promote plants growth in stress conditions].

    Science.gov (United States)

    Napora, Anna; Kacprzak, Małgorzata; Nowak, Kamil; Grobelak, Anna

    2015-01-01

    The growth of plants under stress conditions is often assisted by microorganisms colonizing the rhizosphere (the root zone of the highest microbial activity). One of the most important bacterial groups to encourage the growth of plants (PGPB) are endophytes. These microorganisms penetrate living cells of plants and there they lead the microbiological activity as endosymbionts. These microorganisms can effectively promote the growth of plants under stress conditions and stimulate biochemical activities: nitrogen fixation, production of growth hormones (auxins, cytokinins and gibberellins), reduction of the high concentration of ethylene as well as facilitation of the collection plant minerals and water. This paper is an attempt to summarize the current state of knowledge about the biochemical activity of bacterial endophytes.

  5. Intelligent control of air conditioning with economizer tx2; Klimaanlage mit Economiser tx2 intelligent geregelt

    Energy Technology Data Exchange (ETDEWEB)

    Hediger, M.; Schumacher, B. [Siemens Building Technologies AG, Staefa (Switzerland). Landis und Staefa Div.

    1999-03-01

    At Ziegler Druck- und Verlags AG (printing and publishing house), CH Winterhtur, an air conditioning plant operates since middle of 1997 requiring mechanical cooling only a few days annually. The air conditioning concept is based on an adiabatic cooling process and a control strategy where all control variables operate within a setpoint field using cost variables. As simulation and experience from other projects show, energy savings up to 50% can be expected. (orig.) [Deutsch] Bei der Ziegler Druck- und Verlags-AG in Winterthur/Schweiz ist seit Mitte 1997 eine Klimaanlage in Betrieb, die nur noch an ganz wenigen Tagen im Jahr mechanisch erzeugte Kaelte benoetigt. Das Klimatisierungskonzept stuetzt sich auf adiabatische Kuehlung sowie eine neuartige Regelphilosophie, die alle Regelprozesse innerhalb eines definierten Sollwertfeldes nach wirtschaftlichen Vorgaben ausfuehrt. Modellrechnungen wie auch konkrete Erfahrungen aus anderen Projekten lassen mit dieser Art von Regelung Energiekosteneinsparungen von bis zu 50 Prozent erwarten. (orig.)

  6. 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.

  7. Plant response to sunflower seeds to osmotic conditioning

    Directory of Open Access Journals (Sweden)

    Camila Santos Barros de Morais

    2014-10-01

    Full Text Available The aim of this study was to evaluate the effect of seeds osmotic conditioning in seedlings emergence and plants performance of sunflower. Three lots of seeds sunflower (Catissol, was submited to osmotic conditioning with polyethylene glycol solution, –2,0 MPa in aerated system, under 15 ºC for 8 hour and then was evaluated for germination tests and vigour. Under filed conditions was conducted emergency evaluations of seedling, plants development as well as the productivity and seeds quality, and the accumulation of nutrients in the seeds. The osmotic conditioning improve the survival of seedling, the dry matter mass to aerial part of plants from 60 days after sowing and oil content, in lots with low seeds physiological quality. The osmotic conditioning not increase the seeds yield but promotes the vigour of seeds produced, regardless of the lot used for sowing seeds.

  8. New principle of organization of working process of air conditioning systems at railway and sea transport

    Directory of Open Access Journals (Sweden)

    Andrey KRAJNIUK

    2008-01-01

    Full Text Available An indispensable component of ensuring safe control of railway and sea transport in conditions of hot climate is maintenance of comfortable temperature of air in control cabins and living spaces. Now the interest is restored to use the Air Refrigerating Plants (ARP as they have a wide potential of low-temperature cooling without use of ozone-destructive cooling agents prohibited by decision of the Montreal meeting. At the same time, air conditioning installations on the basis of turbo-expanders have low refrigerating factor, they are very expensive in manufacturing and require a high level of maintenance service.Alternative trend of perfection of air refrigeration units is connected with a new principle of organization of working process, based on the use as expander and compressor of aggregates of cascade exchanger of pressure (CPE. Besides of unsurpassed efficiency of exchange processes, CPE is characterized by simplicity of design and high reliability, including, due to low frequency of rotation (2000-3000 min-1 with practically absence of consumption of mechanical energy on the drive of the rotor. The attractive aspect of application of equipment of conditioning with CPE is the opportunity of organization of working process only due to thermal energy including the utilization in the heat-power installation of transport vehicle.

  9. 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)

  10. Effect of air conditioning and chair cushion on scrotal temperature.

    Science.gov (United States)

    Song, Gook-Sup; Kim, Wonwoo; Seo, Ju Tae

    2008-08-01

    The hypothesis of this study is that the air conditioning temperature and thickness of the chair cushion affect a man's scrotal, and consequently testicular, temperature. Ten healthy male subjects volunteered for the study (age: 23.4 +/- 2.4 years; height: 173.8 +/- 5.09 cm; weight: 71.6 +/- 9.7 kg; body fat ratio: 18.6 +/- 4.1%). The air conditioning temperature was controlled at 18 degrees C to represent the heating season, and at 26 degrees C to represent the cooling season. The thickness of the chair cushions was varied from 0 to 8 cm at 2 cm intervals. The changes in the scrotal surface temperature (SST) and buttock skin temperature were measured for 120 min. At the ambient temperatures (t(a)) of 18 and 26 degrees C, the average SST were 33.76 +/- 1.28 and 35.02 +/- 0.54 degrees C for the chair cushion thickness (C(thk)) of 0 cm, 33.87 +/- 1.07 and 34.96 +/- 0.75 degrees C for C(thk) 2 cm, 33.91 +/- 0.84 and 35.03 +/- 0.85 degrees C for C(thk) 4 cm, 34.42 +/- 0.89 and 35.02 +/- 0.63 degrees C for C(thk) 6 cm, and 34.65 +/- 1.21 and 34.99 +/- 0.62 degrees C for C(thk) 8 cm respectively. SST was significantly affected by the air conditioning temperature (p < 0.001), but was not statistically correlated with the chair cushion thickness.

  11. 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.

  12. Do-It-Yourself Additives Recharge Auto Air Conditioning

    Science.gov (United States)

    2010-01-01

    In planning for a return mission to the Moon, NASA aimed to improve the thermal control systems that keep astronauts comfortable and cool while inside a spacecraft. Goddard Space Flight Center awarded a Small Business Innovation Research (SBIR) contract to Mainstream Engineering Corporation, of Rockledge, Florida, to develop a chemical/mechanical heat pump. IDQ Inc., of Garland, Texas, exclusively licensed the technology and incorporates it into its line of Arctic Freeze products for automotive air conditioning applications. While working on the design, Mainstream Engineering came up with a unique liquid additive called QwikBoost to enhance the performance of the advanced heat pump design.

  13. Investigation of air cleaning system response to accident conditions

    Energy Technology Data Exchange (ETDEWEB)

    Andrae, R.W.; Bolstad, J.W.; Foster, R.D.; Gregory, W.S.; Horak, H.L.; Idar, E.S.; Martin, R.A.; Ricketts, C.I.; Smith, P.R.; Tang, P.K.

    1980-01-01

    Air cleaning system response to the stress of accident conditions are being investigated. A program overview and hghlight recent results of our investigation are presented. The program includes both analytical and experimental investigations. Computer codes for predicting effects of tornados, explosions, fires, and material transport are described. The test facilities used to obtain supportive experimental data to define structural integrity and confinement effectiveness of ventilation system components are described. Examples of experimental results for code verification, blower response to tornado transients, and filter response to tornado and explosion transients are reported.

  14. Sea/Lake Water Air Conditioning at Naval Facilities.

    Science.gov (United States)

    1980-05-01

    r-AO89 262 CIVIL ENGINEERING LAS (NAVY) PONT HUJENEME CA F/6 13/1 SEA/LAKF WATER AIR CONDITIONING AT N4AVAL FACILITIES.u MAY S0 .J B CIAN...AROICC. Brooklyn NY: CO; C’ode (NP (LCDR ATJ Stewart): C’ode 10)28. RDT&ELO. Philadelphia PA: Code III (Castranovo) Philadelphia. PA: Design Div. (R...Governor’s Council On Energy) NEW MEXICO SOLAR ENERGY INST. Dr. Zwibcl Las Cruces NM NY CITY COMMUNITY COLLEGE BROOKLYN , NY (LIBRARY) NYS ENERGY OFFICE

  15. Human requirements in future air-conditioned environments

    DEFF Research Database (Denmark)

    Fanger, Povl Ole

    2001-01-01

    , even though existing standards and guidelines are met. A paradigm shift from rather mediocre to excellent indoor environments is foreseen in the 21st century. Based on existing information and on new research results, five principles are suggested as elements behind a new philosophy of excellence......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...... individual; individual control of the thermal environment should be provided. These principles of excellence are compatible with energy efficiency and sustainability....

  16. 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.

  17. Engine-driven hybrid air-conditioning system

    Institute of Scientific and Technical Information of China (English)

    Chaokui QIN; Hongmei LU; Xiong LIU; Gerhard SCHMITZ

    2009-01-01

    A hybrid air-conditioning system that com-bines an engine-driven chiller with desiccant dehumidifi-cation was configured and experimentally tested to provide reliable data for energy consumption and operation cost. The engine performance and the desiccant wheel perfor-mance were measured and a numeric model previously set up for dehumidification capacity prediction was validated. For a reference building, the results based upon measured data show that under present electricity/gas price ratio, more than 40% of operation cost can be saved by the hybrid system.

  18. Heating control strategy in fresh air processor matched with variable refrigerant flow air conditioning system

    Energy Technology Data Exchange (ETDEWEB)

    Tu Qiu, E-mail: tuqiuky@163.co [Guangzhou Institute of Energy Conversion, Chinese Academy of Science, Guangzhou 510640 (China) and Key Laboratory of Renewable Energy and Gas Hydrate, Chinese Academy of Science, Guangzhou 510640 (China); Mao Shoubo; Feng Yuhai; Guo Defang [Haier Air-Conditioning Electronic Co. Ltd., Qingdao 266510 (China)

    2011-07-15

    Highlights: {yields} A set of fresh air processor matched with VRF AC has been designed. {yields} The heating control model of variable condensation temperature target has been presented {yields} The control strategy can realize reliable running, high control accuracy and energy-saving. {yields} The control model is universal for fresh air processors with different capacities. -- Abstract: The fresh air processor (FAP), matched with the variable refrigerant flow air conditioning system (VRF AC), has been developed. Two control methods were adopted to control the system running and air outlet temperature, contrastively. The first method is that the running frequency in heating mode is adjusted in terms of the ordinary control method of VRF, i.e., constant condensation temperature. The experiment demonstrates the control method is not feasible. For nominal heating under different static pressure and defrosting under 200 Pa static pressure, the system fluctuates frequently. And for high temperature heating, the air outlet temperature far exceeds the target temperature. Furthermore, the control model of variable condensation temperature target has been presented, and the heat transfer correction factor is introduced into the control model. And the control parameters in the model are determined by experiment. The control model is universal for FAPs with different capacities by identifying and choosing the heat transfer correction factor in the control program. For low temperature heating, the method of switching rotation speed of the motor can be adopted to enhance air outlet temperature to 22 {sup o}C. The control strategy can provide guide for the design and application of FAP.

  19. Exergy and Thermoeconomic Analyses of Central Receiver Concentrated Solar Plants Using Air as Heat Transfer Fluid

    Directory of Open Access Journals (Sweden)

    Claudia Toro

    2016-10-01

    Full Text Available The latest developments in solar technologies demonstrated that the solar central receiver configuration is the most promising application among concentrated solar power (CSP plants. In CSPs solar-heated air can be used as the working fluid in a Brayton thermal cycle and as the heat transfer fluid for a Rankine thermal cycle as an alternative to more traditional working fluids thereby reducing maintenance operations and providing the power section with a higher degree of flexibility To supply thermal needs when the solar source is unavailable, an auxiliary burner is requested. This configuration is adopted in the Julich CSP (J-CSP plant, operating in Germany and characterized by a nominal power of 1.5 MW, the heat transfer fluid (HTF is air which is heated in the solar tower and used to produce steam for the bottoming Rankine cycle. In this paper, the J-CSP plant with thermal energy storage has been compared with a hybrid CSP plant (H-CSP using air as the working fluid. Thermodynamic and economic performances of all the simulated plants have been evaluated by applying both exergy analysis and thermoeconomic analysis (TA to determine the yearly average operation at nominal conditions. The exergy destructions and structure as well as the exergoeconomic costs of products have been derived for all the components of the plants. Based on the obtained results, the thermoeconomic design evaluation and optimization of the plants has been performed, allowing for improvement of the thermodynamic and economic efficiency of the systems as well as decreasing the exergy and exergoeconomic cost of their products.

  20. Bioaerosol deposition on an air-conditioning cooling coil

    Science.gov (United States)

    Wu, Yan; Chen, Ailu; Luhung, Irvan; Gall, Elliott T.; Cao, Qingliang; Chang, Victor Wei-Chung; Nazaroff, William W.

    2016-11-01

    This study is concerned with the role of a fin-and-tube heat exchanger in modifying microbial indoor air quality. Specifically, depositional losses of ambient bioaerosols and particles onto dry (not cooled) and wet (cool) coil surfaces were measured for different airspeeds passing through the test coil. Total, bacterial and fungal DNA concentrations in condensate water produced by a wet coil were also quantified by means of fluorescent dsDNA-binding dye and qPCR assays. Results revealed that the deposition of bioaerosols and total particles is substantial on coil surfaces, especially when wet and cool. The average deposition fraction was 0.14 for total DNA, 0.18 for bacterial DNA and 0.22 for fungal DNA on the dry coil, increasing to 0.51 for total DNA, 0.50 for bacterial DNA and 0.68 for fungal DNA on the wet coil. Overall, as expected, deposition fractions increased with increasing particle size and increasing airspeed. Deposited DNA was removed from the cooling coil surfaces through the flow of condensing water at a rate comparable to the rate of direct deposition from air. A downward trend of bacterial and fungal DNA measured in condensate water over time provides suggestive evidence of biological growth on heat exchangers during nonoperational times of a ventilation system. This investigation provides new information about bioaerosol deposition onto a conventional fin-and-tube cooling coil, a potentially important factor influencing indoor exposure to microbial aerosols in air-conditioned buildings.

  1. An effective silencer design for artificially air conditioned environment.

    Science.gov (United States)

    Fujiwara, Kyoji; Pang, Li Feng

    2004-11-01

    An effective silencer for an air conditioning duct is studied. A duct with an acoustically soft boundary is employed as an effective silencer. On the acoustically soft boundary the sound pressure is zero and it is impossible to realize such boundary in the air-borne sound field, because of the non-existence of a much lighter medium than the air. In this study, the arrangement of one-quarter wave-length acoustic tubes is employed as a soft boundary. This acoustic tube has frequency dependence, but the sound pressure becomes nearly zero at the tube mouth around the odd resonance frequency. The relation between the noise reduction efficiency and this acoustically soft boundary is examined experimentally and more than 40 dB noise reduction is obtained in a one-half octave band around the first resonance frequency. It is also made clear that more than one wave length of soft boundary is required to get enough reduction compared with the reduction obtained in the case of quite a long soft boundary.

  2. Control of Computer Room Air Conditioning using IT Equipment Sensors

    Energy Technology Data Exchange (ETDEWEB)

    Bell, Geoffrey C.; Storey, Bill; Patterson, Michael K.

    2009-09-30

    The goal of this demonstration was to show how sensors in IT equipment could be accessed and used to directly control computer room air conditioning. The data provided from the sensors is available on the IT network and the challenge for this project was to connect this information to the computer room air handler's control system. A control strategy was developed to enable separate control of the chilled water flow and the fans in the computer room air handlers. By using these existing sensors in the IT equipment, an additional control system is eliminated (or could be redundant) and optimal cooling can be provided saving significant energy. Using onboard server temperature sensors will yield significant energy reductions in data centers. Intel hosted the demonstration in its Santa Clara, CA data center. Intel collaborated with IBM, HP, Emerson, Wunderlich-Malec Engineers, FieldServer Technologies, and LBNL to install the necessary components and develop the new control scheme. LBNL also validated the results of the demonstration.

  3. 40 CFR 86.161-00 - Air conditioning environmental test facility ambient requirements.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Air conditioning environmental test... conditioning environmental test facility ambient requirements. The goal of an air conditioning test facility is..., within the test cell, during all phases of the air conditioning test sequence to 95 ±2 °F on average and...

  4. Energy efficient air-conditioning technology for a healthier climate; Energieeffiziente Klimatechnik fuer ein gesundes Raumklima

    Energy Technology Data Exchange (ETDEWEB)

    Hartl, Thorsten [ebm-papst Motoren und Ventilatoren GmbH, St. Florian (Austria)

    2011-07-01

    Since climate and indoor air quality have a great impact on concentration, health and well being, it is important to provide good indoor air for example in classrooms. The use of air conditioning equipment enables an optimal air-conditioning, whether in new buildings or building alterations or renovations. Energy-saving EC fans in these air conditioning systems provide an efficient and quiet ventilation meeting the requirements. Thus, the contribution under consideration reports on centrifugal fans.

  5. Absorption and adsorption chillers applied to air conditioning systems

    Science.gov (United States)

    Kuczyńska, Agnieszka; Szaflik, Władysław

    2010-07-01

    This work presents an application possibility of sorption refrigerators driven by low temperature fluid for air conditioning of buildings. Thermodynamic models were formulated and absorption LiBr-water chiller with 10 kW cooling power as well as adsorption chiller with silica gel bed were investigated. Both of them are using water for desorption process with temperature Tdes = 80 °C. Coefficient of performance (COP) for both cooling cycles was analyzed in the same conditions of the driving heat source, cooling water Tc = 25 °C and temperature in evaporator Tevap = 5 °C. In this study, the computer software EES was used to investigate the performance of absorption heat pump system and its behaviour in configuration with geothermal heat source.

  6. Controlled environment fumigation chambers for the study of reactive air pollutant effects on plants

    Science.gov (United States)

    Stokes, N. J.; Lucas, P. W.; Nicholas Hewitt, C.

    The design and construction of eight 1-m 3 fumigation chambers for exposing plants to reactive air pollutants at low concentrations are reported. Teflon surfaces are used where possible to minimize the adsorption, absorption, desorption and chemical reaction of the pollutants. A purified ambient air supply, to which metered quantities of gaseous pollutants are added, is used to give two air changes per minute at constant, low, pollutant concentrations. Comparative analysis of the chambers indicates that conditions may be maintained with a significant degree of precision, i.e. temperature ±0.3°C, RH ±6%, light intensity ±5 μmol m -2 s -1. Boundary layer analysis from models of cherry tree ( Prunus avium) leaves indicate that the minimum conductance value within these chambers is 2 cm s -1.

  7. Prizes awarded in fiscal 1999 by the Minister for International Trade and Industry on factories having applied excellent energy management. Energy conservation by installing fuel cell power generation facilities utilizing methane gas generated from waste water treatment plants / Improvements toward a clean room and energy saving air conditioning system; 1999 nendo energy kanri yuryo kojo tsusho sangyo daijin hyosho jusho. 1999 nendo shigen energy sho chokan hyosho jusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-04-01

    In order to achieve energy conservation in a waste water treatment plant in a brewery factories, an anaerobic treatment facility was introduced, and a fuel cell power generation facility effectively utilizing methane gas generated from the anaerobic waste water treatment plant was installed. This has resulted in large reduction in the operating number of blowers in the waste water treatment facility of activated sludge system. In addition, electric power, steam, and hot water generated from the fuel cells are effectively utilized as the factory utility. In energy conservation in an optical communication device manufacturing factory, the fan filter unit system was adopted, having been changed from the circulation air conditioner, a conventional type air conditioning system. The present system is a circulation system integrating the fan with the filter, making it possible to circulate air in the room to perform control of temperature, humidity, and dust in a clean room. Thus, the system has eliminated the circulating air conditioner, and reduced the air conditioner capacity by 42% and power consumption by 58.6% compared with those in the conventional circulation system. (NEDO)

  8. Microbiological air quality in an urban solid waste selection plant

    Directory of Open Access Journals (Sweden)

    Angela Del Cimmuto

    2010-03-01

    Full Text Available

    Background: Exposure to bioaerosols may pose health risks to workers operating in the processing of Urban Solid Waste (USW. The aim of this study is to evaluate microbiological air quality within an USW selection facility.

    Methods: Nine sampling points in an USW selection plant situated in central-southern Italy were selected. One outdoor sampling point provided the background data. Sampling was performed on a yearly basis (2005 – 2009 upon request by the management of the selection plant. Total Mesophilic Counts (TMC, as well as fungal and Gram-negative concentrations were determined.

    Results: The highest viable fungal particles concentrations (medians were found in waste delivery areas (about 20000 CFU/m3, while the lowest were found in the control rooms (485 – 967 CFU/m3. TMC (median was highest (6116 CFU/m3 at the delivery pit, followed by the machine shop (3147 CFU/m3, where no waste processing takes place. Medians of Gram-negative bacteria are below the suggested Occupational Exposure Limit of 1000 CFU/m3, although this limit was exceeded at several single time-points in the waste delivery areas, and also in a personnel resting room. The lowest Gram-negative contamination was found in the control rooms (medians <1 CFU/m3.

    Conclusions: Some areas within a USW selection plant act as internal sources of contamination towards those areas where partially processed waste, or no waste at all, is present. Well-designed air flows, or carefullythought positioning of areas that are not directly involved in waste processing are necessary and effective in obtaining

  9. Plant Growth and Morphogenesis under Different Gravity Conditions: Relevance to Plant Life in Space.

    Science.gov (United States)

    Hoson, Takayuki

    2014-05-16

    The growth and morphogenesis of plants are entirely dependent on the gravitational acceleration of earth. Under microgravity conditions in space, these processes are greatly modified. Recent space experiments, in combination with ground-based studies, have shown that elongation growth is stimulated and lateral expansion suppressed in various shoot organs and roots under microgravity conditions. Plant organs also show automorphogenesis in space, which consists of altered growth direction and spontaneous curvature in the dorsiventral (back and front) directions. Changes in cell wall properties are responsible for these modifications of growth and morphogenesis under microgravity conditions. Plants live in space with interesting new sizes and forms.

  10. Plant Growth and Morphogenesis under Different Gravity Conditions: Relevance to Plant Life in Space

    Directory of Open Access Journals (Sweden)

    Takayuki Hoson

    2014-05-01

    Full Text Available The growth and morphogenesis of plants are entirely dependent on the gravitational acceleration of earth. Under microgravity conditions in space, these processes are greatly modified. Recent space experiments, in combination with ground-based studies, have shown that elongation growth is stimulated and lateral expansion suppressed in various shoot organs and roots under microgravity conditions. Plant organs also show automorphogenesis in space, which consists of altered growth direction and spontaneous curvature in the dorsiventral (back and front directions. Changes in cell wall properties are responsible for these modifications of growth and morphogenesis under microgravity conditions. Plants live in space with interesting new sizes and forms.

  11. Plant monitoring of air quality around waste incinerators

    Energy Technology Data Exchange (ETDEWEB)

    Tonneijck, A.E.G.; Dijk, C.J. van; Dueck, T.A. [Plant Research International, Wageningen (Niger). Dept. of Crop and Production Ecology

    2002-07-01

    Since the early 1990's, three new waste incineration plants have come into operation in agricultural regions in The Netherlands. Multi-year standardised biomonitoring programmes around these incinerators were set up to determine the absence of adverse effects on quality of crop produce due to the incineration of waste. Depending on time of year, plants of kale (Brassica oleracea) and spinach (Spinacia oleracea) were cultivated for use as accumulators of cadmium (Cd), mercury (Hg) and polycyclic aromatic hydrocarbons (PAHs). Trends in fluoride contents were followed by sampling field-grown pasture grass. Cow milk was sampled to determine the concentrations of dioxins. Plants of gladiola (Gladiolus gandavensis) were used for the assessment of visible injury by ambient fluoride in one programme only. The results of many years of biomonitoring showed that the emissions of the waste incinerators did not affect the quality of crop produce and cow milk. Concentrations of the various components in these products were generally similar to background levels and did not exceed standards for maximum allowable concentrations. On one occasion, concentrations of PAHs in spinach were clearly enhanced due to the use of wood-preserving compounds at a barn close to the monitoring site. This incident reveals that our biomonitoring projects are an appropriate tool to detect changes in air quality. (orig.)

  12. Plant neighbour identity matters to belowground interactions under controlled conditions.

    Directory of Open Access Journals (Sweden)

    Cristina Armas

    Full Text Available BACKGROUND: Root competition is an almost ubiquitous feature of plant communities with profound effects on their structure and composition. Far beyond the traditional view that plants interact mainly through resource depletion (exploitation competition, roots are known to be able to interact with their environment using a large variety of mechanisms that may inhibit or enhance access of other roots to the resource or affect plant growth (contest interactions. However, an extensive analysis on how these contest root interactions may affect species interaction abilities is almost lacking. METHODOLOGY/PRINCIPAL FINDINGS: In a common garden experiment with ten perennial plant species we forced pairs of plants of the same or different species to overlap their roots and analyzed how belowground contest interactions affected plant performance, biomass allocation patterns, and competitive abilities under abundant resource supply. Our results showed that net interaction outcome ranged from negative to positive, affecting total plant mass and allocation patterns. A species could be a strong competitor against one species, weaker against another one, and even facilitator to a third species. This leads to sets of species where competitive hierarchies may be clear but also to groups where such rankings are not, suggesting that intransitive root interactions may be crucial for species coexistence. CONCLUSIONS/SIGNIFICANCE: The outcome of belowground contest interactions is strongly dependent on neighbours' identity. In natural plant communities this conditional outcome may hypothetically help species to interact in non-hierarchical and intransitive networks, which in turn might promote coexistence.

  13. 40 CFR 86.1832-01 - Optional equipment and air conditioning for test vehicles.

    Science.gov (United States)

    2010-07-01

    ... Optional equipment and air conditioning for test vehicles. For test vehicles selected under §§ 86.1822-01... be expected to influence emissions include, but are not limited to: air conditioning, power steering...) Except for air conditioning, where it is expected that 33 percent or less of a car line, within a test...

  14. 24 CFR 3280.813 - Outdoor outlets, fixtures, air-conditioning equipment, etc.

    Science.gov (United States)

    2010-04-01

    ... Electrical Systems § 3280.813 Outdoor outlets, fixtures, air-conditioning equipment, etc. (a) Outdoor.../or air conditioning equipment located outside the manufactured home, shall have permanently affixed, adjacent to the outlet, a metal tag which reads: This Connection Is for Air Conditioning Equipment Rated at...

  15. 40 CFR 86.162-03 - Approval of alternative air conditioning test simulations.

    Science.gov (United States)

    2010-07-01

    ... alternative air conditioning test simulations. (a) Upon petition from a manufacturer or upon the Agency's own initiative, the Administrator will approve a simulation of the environmental cell for air conditioning test... the tailpipe emissions, air conditioning compressor load, and fuel economy. (2) For any simulation...

  16. 40 CFR 86.166-12 - Method for calculating emissions due to air conditioning leakage.

    Science.gov (United States)

    2010-07-01

    ... to air conditioning leakage. 86.166-12 Section 86.166-12 Protection of Environment ENVIRONMENTAL... for calculating emissions due to air conditioning leakage. This section describes procedures used to determine a refrigerant leakage rate in grams per year from vehicle-based air conditioning units. The...

  17. Air leakage analysis of research reactor HANARO building in typhoon condition for the nuclear emergency preparedness

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Goany Up; Lee, Hae Cho; Kim, Bong Seok; Kim, Jong Soo; Choi, Pyung Kyu [Dept. of Emergency Preparedness, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-12-15

    To find out the leak characteristic of research reactor 'HANARO' building in a typhoon condition MELCOR code which normally is used to simulate severe accident behavior in a nuclear power plant was used to simulate the leak rate of air and fission products from reactor hall after the shutdown of the ventilation system of HANARO reactor building. For the simulation, HANARO building was designed by MELCOR code and typhoon condition passed through Daejeon in 2012 was applied. It was found that the leak rate is 0.1%·day{sup -1} of air, 0.004%·day{sup -1} of noble gas and 3.7×10{sup -5}%·day{sup -1} of aerosol during typhoon passing. The air leak rate of 0.1%·day can be converted into 1.36 m{sup 3}·hr{sup -1} , but the design leak rate in HANARO safety analysis report was considered as 600 m3·hr{sup -1} under the condition of 20 m·sec{sup -1} wind speed outside of the building by typhoon. Most of fission products during the maximum hypothesis accident at HANARO reactor will be contained in the reactor hall, so the direct radiation by remained fission products in the reactor hall will be the most important factor in designing emergency preparedness for HANARO reactor.

  18. 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.

  19. 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.

  20. 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...

  1. Human requirements in future air-conditioned environments

    DEFF Research Database (Denmark)

    Fanger, Povl Ole

    2002-01-01

    though existing standards and guidelines are met. A paradigm shift from rather mediocre to excellent indoor environments is foreseen in buildings in the 21st century. Based on existing information and on new research results, five principles are suggested as elements behind a new philosophy of excellence......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...... to the breathing zone of each individual; individual control of the airflow and/or the thermal environment should be provided. These principles of excellence should be combined with energy efficiency and sustainability of future buildings....

  2. Experimental Research on Liquid Desiccant Air-conditioning Unit

    Directory of Open Access Journals (Sweden)

    Feng Yueyan

    2016-01-01

    Full Text Available An experimental device of liquid desiccant air conditioning system is established. Experimental tests about the temperature difference between diluted solution of inlet and concentrated solution of exit in the solution heat exchanger are carried on, and CaCl2 solution is used as desiccant. Results show that: the fluctuation range in the day at different times of the basic difference of the measured temperature does not exceed 1°C, and the temperature difference between diluted solution of inlet and concentrated solution of exit in solution heat exchanger appears the minimum value of 2.7°C and the maximum value of 10.2°C. Also, the percent of the additional load and the ratio of additional load to the evaporator load are analyzed.

  3. CFD SIMULATION OF AIR ION REGIME IN WORK AREAS AT CONDITION OF ARTIFICIAL AIR IONIZATION

    Directory of Open Access Journals (Sweden)

    M. M. Biliaiev

    2016-02-01

    sources and ions of different polarity; physical processes affecting the formation of ions concentration field. Practical value. The obtained 2D CFD model for calculating the air ions regime in working areas allow to calculate the concentration of ions at the location of the respiratory organs, taking into account the basic physical factors determining the formation of ions concentration fields. It will allow rationally arranged the ionizers in the working premises to create the comfortable working conditions for staff.

  4. Automobile air-conditioning. Its energy and environmental impact

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    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 (maximum 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 international 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-conditioning (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-led 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. (author)

  5. Regulatory Actions - Final Mercury and Air Toxics Standards (MATS) for Power Plants

    Science.gov (United States)

    The U.S. Environmental Protection Agency (EPA) has proposed Mercury and Air Toxics Standards (MATS) for power plants to limit mercury, acid gases and other toxic pollution from power plants. This page describes Federal regulatory actions.

  6. Regulatory Actions - Proposed Mercury and Air Toxics Standards (MATS) for Power Plants

    Science.gov (United States)

    The U.S. Environmental Protection Agency (EPA) has proposed Mercury and Air Toxics Standards (MATS) for power plants to limit mercury, acid gases and other toxic pollution from power plants. This page includes supporting documentation and

  7. Cultivar Differences in Plant Transpiration Rate at High Relative Air Humidity Are Not Related to Genotypic Variation in Stomatal Responsiveness

    DEFF Research Database (Denmark)

    Gebraegziabher, Habtamu Giday; Kjær, Katrine Heinsvig; Ottosen, Carl-Otto

    2015-01-01

    a given cultivar, Tleaf was generally higher, (1.5-3.7°C) at high as compared to moderate RH. Following desiccation, leaf weight loss was differentially enhanced (8-66%) in high RH-grown plants, indicating a wide variation in high RH tolerance. High RH mainly decreased plant water loss during the light......Plants grown at high relative air humidity (RH) often show disturbed water relations due to less responsive stomata. The attenuation of stomatal responsiveness as a result of high RH during leaf expansion depends on the cultivar. We hypothesized that tolerant cultivars to high RH experience a lower...... decline in plant transpiration by high RH, and that the variation in plant transpiration rate can be reflected by differences in leaf temperature (Tleaf). Plant leaf area, stomatal responsiveness to desiccation, together with plant transpiration and leaf temperature at growth conditions were analyzed...

  8. Reversible air-conditioning: admittedly economical and ecological advantages; Climatisation reversible: des atouts economiques et ecologiques reconnus

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1999-06-01

    The energetic qualities of reversible air-conditioners were officially admitted by the French public authorities in the beginning of 1999. An exceptional fiscal amortization is now awarded to reversible appliances with a coefficient of performance superior or equal to 2.5 for an external temperature of 7 deg. C. This dossier on reversible air-conditioning comprises three parts. The first part presents the technique, its indirect contribution to the abatement of the greenhouse effect and its fiscal advantage. Part 2 presents a case study for the calculation of the fiscal amortization, while the third part presents the different existing solutions: split- or multi-split systems, and centralized systems (air systems, air-treatment plants, air distribution systems, water systems, ventilation-convection systems, water-loop heat pumps, variable refrigerating flow rate systems). (J.S.)

  9. Investigations of hydraulic operating conditions of air lift pump with three types of air-water mixers

    Directory of Open Access Journals (Sweden)

    Kalenik Marek

    2015-03-01

    Full Text Available Investigations of hydraulic operating conditions of air lift pump with three types of air-water mixers. The paper presents the analysis of results of the investigations concerning the influence of various constructive solutions of the air-water mixers on hydraulic operating conditions of the air lift pump. The scope of the investigations encompassed the determination of characteristics of delivery head and delivery rate for three types of air-water mixers applied in the constructed air lift pump. Using the obtained results, the efficiency of the three types of air-water mixers applied in this air lift pump was determined. The analysis was carried out and there was checked whether the improved analytical Stenning-Martin model can be used to design air lift pumps with the air-water mixers of these types. The highest capacity in the water transport was reached by the air lift pump with the 1st type air-water mixer, the lowest one – with the 3rd type air-water mixer. The water flow in the air lift pump increases along with the rise in the air flow. The lower are the hydraulic losses generated during flow of the air flux by the air-water mixer, the higher is the air lift pump capacity. Along with the rise in the water delivery head, the capacity of the air lift pump decreases. The highest efficiency is reached by the air lift pump with the 1st type air-water mixer, the lowest – with the 3st type air-water mixer. The efficiency of the air lift pump for the three investigated types of air-water mixers decreases along with the rise in air flow rate and water delivery head. The values of submergence ratio (h/L of the delivery pipe, calculated with the use of the improved analytical Stenning-Martin model, coincide quite well with the values of h/L determined from the measurements.

  10. Radial distributions of air plants: a comparison between epiphytes and mistletoes.

    Science.gov (United States)

    Taylor, Amanda; Burns, Kevin

    2016-04-01

    Vertical gradients of light and humidity within forest canopies are major predictors of air plant distributions. Although this pattern was first recognized over 120 years ago, few studies have considered an additional axis of resource availability, which exists radially around the trunks of trees. Here, we explored the radial distributions of mistletoes and epiphytes in relation to gradients of light and humidity around the trunks of their south-temperate host trees. Additionally, we correlated microclimate occupancy with plant physiological responses to shifting resource availability. The radial distributions of mistletoes and epiphytes were highly directional, and related to the availability of light and humidity, respectively. Mistletoes oriented northwest, parallel to gradients of higher light intensity, temperature, and lower humidity. Comparatively, epiphytes oriented away from the sun to the southeast. The rate of CO2 assimilation in mistletoes and photochemical efficiency of epiphytes was highest in plants growing in higher light and humidity environments, respectively. However, the photosynthetic parameters of mistletoes suggest that they are also efficient at assimilating CO2 in lower light conditions. Our results bridge a key gap in our understanding of within-tree distributions of mistletoes and epiphytes, and raise further questions on the drivers of air plant distributions.

  11. Understanding the Dehumidification Performance of Air-Conditioning Equipment at Part-Load Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Don B. Shirey III; Hugh I. Henderson Jr; Richard A. Raustad

    2006-01-01

    Air conditioner cooling coils typically provide both sensible cooling and moisture removal. Data from a limited number of field studies (Khattar et al. 1985; Henderson and Rengarajan 1996; Henderson 1998) have demonstrated that the moisture removal capacity of a cooling coil degrades at part-load conditions--especially when the supply fan operates continuously while the cooling coil cycles on and off. Degradation occurs because moisture that condenses on the coil surfaces during the cooling cycle evaporates back into air stream when the coil is off. This degradation affects the ability of cooling equipment to maintain proper indoor humidity levels and may negatively impact indoor air quality. This report summarizes the results of a comprehensive project to better understand and quantify the moisture removal (dehumidification) performance of cooling coils at part-load conditions. A review of the open literature was initially conducted to learn from previous research on this topic. Detailed performance measurements were then collected for eight cooling coils in a controlled laboratory setting to understand the impact of coil geometry and operating conditions on transient moisture condensation and evaporation by the coils. Measurements of cooling coil dehumidification performance and space humidity levels were also collected at seven field test sites. Finally, an existing engineering model to predict dehumidification performance degradation for single-stage cooling equipment at part-load conditions (Henderson and Rengarajan 1996) was enhanced to include a broader range of fan control strategies and an improved theoretical basis for modeling off-cycle moisture evaporation from cooling coils. The improved model was validated with the laboratory measurements, and this report provides guidance for users regarding proper model inputs. The model is suitable for use in computerized calculation procedures such as hourly or sub-hourly building energy simulation programs (e

  12. Plants + microbes: Innovative food crop systems that also clean air and water

    Science.gov (United States)

    Nelson, Mark; Wolverton, B. C.

    The limitations that will govern bioregenerative life support applications in space, especially volume and weight, make multi-purpose systems advantageous. This paper outlines two systems which utilize plants and associated microbial communities of root or growth medium to both produce food crops and clean air and water. Underlying these approaches are the large numbers and metabolic diversity of microbes associated with roots and found in either soil or other suitable growth media. It is known that most biogeochemical cycles have a microbial link, and the ability of microbes to metabolize virtually all trace gases, whether of technogenic or biogenic origin, have long been established. Wetland plants and soil/media also been extensively researched for their ability to purify wastewaters of all kinds of potential water pollutants, from nutrients like N and P, to heavy metals and a range of complex industrial pollutants. There is a growing body of research on the ability of higher plants to purify air and water. Associated benefits of these approaches is that by utilizing natural ecological processes, the cleansing of air and water can be done with little or no energy inputs. Soil and root microorganisms respond to changing pollutant types by an increase of the types of organisms with the capacity to use these compounds. Thus living systems have an extraordinary adaptive capacity as long as the starting populations are sufficiently diverse. It is known that tightly sealed environments, from office buildings to spacecraft, can have hundreds or even thousands of potential air pollutants, depending on the materials and machines enclosed. Human waste products carry a plethora of microbes can are readily used in the process of converting its organic load to forms that can be utilized by green plants. Having endogenous means of responding to changing air and water quality conditions represents safety factors which operate without the need for human direction. We will

  13. Plants + soil/wetland microbes: Food crop systems that also clean air and water

    Science.gov (United States)

    Nelson, Mark; Wolverton, B. C.

    2011-02-01

    The limitations that will govern bioregenerative life support applications in space, especially volume and weight, make multi-purpose systems advantageous. This paper outlines two systems which utilize plants and associated microbial communities of root or growth medium to both produce food crops and clean air and water. Underlying these approaches are the large numbers and metabolic diversity of microbes associated with roots and found in either soil or other suitable growth media. Biogeochemical cycles have microbial links and the ability of microbes to metabolize virtually all trace gases, whether of technogenic or biogenic origin, has long been established. Wetland plants and the rootzone microbes of wetland soils/media also been extensively researched for their ability to purify wastewaters of a great number of potential water pollutants, from nutrients like N and P, to heavy metals and a range of complex industrial pollutants. There is a growing body of research on the ability of higher plants to purify air and water. Associated benefits of these approaches is that by utilizing natural ecological processes, the cleansing of air and water can be done with little or no energy inputs. Soil and rootzone microorganisms respond to changing pollutant types by an increase of the types of organisms with the capacity to use these compounds. Thus living systems have an adaptive capacity as long as the starting populations are sufficiently diverse. Tightly sealed environments, from office buildings to spacecraft, can have hundreds or even thousands of potential air pollutants, depending on the materials and equipment enclosed. Human waste products carry a plethora of microbes which are readily used in the process of converting its organic load to forms that can be utilized by green plants. Having endogenous means of responding to changing air and water quality conditions represents safety factors as these systems operate without the need for human intervention. We review

  14. Modern air protection technologies at thermal power plants (review)

    Science.gov (United States)

    Roslyakov, P. V.

    2016-07-01

    Realization of the ecologically safe technologies for fuel combustion in the steam boiler furnaces and the effective ways for treatment of flue gases at modern thermal power plants have been analyzed. The administrative and legal measures to stimulate introduction of the technologies for air protection at TPPs have been considered. It has been shown that both the primary intrafurnace measures for nitrogen oxide suppression and the secondary flue gas treatment methods are needed to meet the modern ecological standards. Examples of the environmentally safe methods for flame combustion of gas-oil and solid fuels in the boiler furnaces have been provided. The effective methods and units to treat flue gases from nitrogen and sulfur oxides and flue ash have been considered. It has been demonstrated that realization of the measures for air protection should be accompanied by introduction of the systems for continuous instrumentation control of the composition of combustion products in the gas path of boiler units and for monitoring of atmospheric emissions.

  15. Measurements of volatile hydrocarbons in ambient air coking plant `Walbrzych`

    Energy Technology Data Exchange (ETDEWEB)

    Michalski, R.; Weglarz, A.; Skrok, R. [Polish Academy of Sciences, Zabrze (Poland). Inst. of Environmental Engineering

    1998-12-31

    The air is a matrix very difficult to handle. In addition, the pollutants are usually present at very low concentrations. Many techniques can be used to collect air samples. The simplest way is to use special containers, but this procedure is expensive and time-consuming. The adsorption of pollutants on adsorbents shows a growing interest, despite the difficulty to choose the appropriate support in order to obtain quantitative yields. To overcome this problem, two or three types of adsorbents may be used in series for collecting a wide range of analytes. In addition, the miniaturization of these techniques (i.e. microtraps and solid-phase microextraction) is also very promising: easy to handle, low cost, no solvent required, detection limits at ppt level when sensitive detectors are used. If we have no money for this modern equipment we must use traditional methods for compounds determination. This paper describes measurements of volatile hydrocarbons (such as benzene, toluene, ethylbenzene, xylene and phenol) in ambient air of coking plant `Walbrzych` Measuring points were at streets: Beethoven 4, Dworcowa 2, Kosteckiego 5 and Zamkowa 1. BTEX were collected on graphitized carbon and phenol on Chromosorb 102. After that samples were extracted by solvents (dichloromethane for BTEX or benzene for phenol). Next step was the analysis by gas chromatography with flame ionization detector without preconcentration. The lower limit of detection was circa 0.01 {mu}g/m{sup 3} for each of the determined compounds. These measurements of hydrocarbons in town of Walbrzych were performed for two years from 1996 to 1998. 2 tabs.

  16. 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

  17. Desiccant dehumidification in decentralized air conditioning systems; Einsatz der Sorptionstechnik in der dezentralen Klimatisierung von Gebaeuden

    Energy Technology Data Exchange (ETDEWEB)

    Busweiler, Ulrich [Fachhochschule Giessen-Friedberg (Germany)

    2009-01-15

    Dehumidification of supply air with adsorption wheels, which is known from desiccant cooling systems, is now applied to small air handling units which condition the air of one single room. There is an increase in comfort in winter by recovery of moisture. In summer, dehumidification and cooling of air are ensured by an absolutely dry process without any hygienic risk. (orig.)

  18. Study on the design schemes of the air-conditioning system in a gymnasium

    Science.gov (United States)

    Zhang, Yujin; Wu, Xinwei; Zhang, Jing; Pan, Zhixin

    2017-08-01

    In view of designing the air conditioning project for a gymnasium successfully, the cooling and heating source schemes are fully studied by analyzing the surrounding environment and energy conditions of the project, as well as the analysis of the initial investment and operating costs, which indicates the air source heat pump air conditioning system is the best choice for the project. The indoor air conditioning schemes are also studied systematically and the optimization of air conditioning schemes is carried out in each area. The principle of operating conditions for the whole year is followed and the quality of indoor air and energy-saving are ensured by the optimized design schemes, which provide references for the air conditioning system design in the same kinds of building.

  19. Human requirements in future air-conditioned environments

    DEFF Research Database (Denmark)

    Fanger, Povl Ole

    1999-01-01

    : better indoor air quality increases productivity and decreases SBS symptoms; unnecessary indoor pollution sources should be avoided; the air should be served cool and dry to the occupants; small amounts of clean air should be served gently, close to the breathing zone of each individual; individual...

  20. Experimental Investigation on the Effect of Phase Change Materials on Compressed Air Expansion in CAES Plants

    Directory of Open Access Journals (Sweden)

    Beatrice Castellani

    2015-07-01

    Full Text Available The integration of renewable energy in the electrical grid is challenging due to the intermittent and non-programmable generated electric power and to the transmission of peak power levels. Several energy storage technologies have been studied to find a solution to these issues. In particular, compressed air energy storage (CAES plants work by pumping and storing air into a vessel or in an underground cavern; then when energy is needed, the pressurized air is expanded in an expansion turbine. Several CAES configurations have been proposed: diabatic, adiabatic and isothermal. The isothermal process seems to be the most promising to improve the overall efficiency. It differs from conventional CAES approaches as it employs near-isothermal compression and expansion. Currently, there are no commercial isothermal CAES implementations worldwide, but several methods are under investigation. In this paper, the use of phase change materials (PCM for isothermal air expansion is discussed. Air expansion tests in presence of PCM were carried out in a high-pressure vessel in order to analyze the effect of PCM on the process. Results show that in presence of PCM near isothermal expansion conditions occur and therefore they affect positively the value of the obtainable expansion work.

  1. Influence of the inlet air in efficiency of photocatalytic devices for mineralization of VOCs in air-conditioning installations.

    Science.gov (United States)

    Jimenez-Relinque, E; Castellote, M

    2014-10-01

    Nowadays, a large proportion of photocatalytic oxidation (PCO) devices are being implemented in heating, ventilation and air-conditioning systems. However, no systematic studies have been carried out regarding the influence of inlet air preconditioning. To analyse the impact of the inlet air-conditions into photocatalytic efficiency, a simulated air-conditioning duct with flowing gas through inside was designed. Isobutylene was chosen as the target VOCs. The concentration in the gas phase was monitored using a photoionization detector. The influence of flow rate, relative humidity and temperature on the VOC removal efficiency was analysed. Experimental results were presented in terms of gas-removal efficiency (η) and clean air delivery rate (CADR) and analysed on a kinetic basis. From them, the weight of each parameter in the global process has been determined, from bigger to smaller contribution, flow>temperature>relative humidity. Also, the relevance of the inlet air conditions has been illustrated in a model room in order to determinate the time necessary to obtain a threshold value accomplishing with enough air quality and the energy consumption of the device. Additionally, the photocatalytic decontamination has been assimilated to the "air exchange rate", a parameter commonly used in indoor air quality studies. The results show that preconditioning of air can improve the efficiency of photocatalytic devices and bring important energy savings.

  2. Study the air pollution due to Dorud Cement Plant (in Iran

    Directory of Open Access Journals (Sweden)

    Vahid Mokhtari

    2016-09-01

    Full Text Available Cement industry is one of the most important industries in the country. Dorud Cement Plant is one of the largest and oldest Iran's cement factories, which is working in the center of the city of Dorud. In this study, aimed to investigate air pollution resulting from Dorud cement plant, the parameters of CO, CO2, O2, NO, NO2, NOx, SO2, dry dust particles, particles weight and environmental particulates of PM10 and PM2.5 were measured with conventional methods of measuring emissions from industrial chimneys and by using automatic measuring equipment, and the rates of emissions from the chimneys of the plant were calculated during a working year. These measurements were made over three months, from February 20, 2015 to May 21, 2015, at 3 stations of Link1-k1, Link2-k1 and Link3-k1, which are the chimneys of the three-lines of the plant. It was found in this study that the chimney No. 3 enters the maximum contaminant into the environment. The results also showed that based on the standards defined for the cement industry, Dorud cement plant meets the relative optimal conditions in terms of comparing performance with the standards, and the emissions from the factory are less than the enacted standards for this industry. Also, the preventive measures and equipment for reducing emissions established in this industrial unit have a relative utility. In this study, the factors including type of raw materials used, old production lines and old factory equipment, type of producing cement and proximity to the city were determined as main reasons for the emissions produced by this industry. Also, some management solutions such as the use of environment designing inside the manufacturing process of the plant and outside the plant, using flame-reducing, construction of a new phase and relocating the plant were suggested to reduce emissions from Dorud cement plants.

  3. Intraoral air pressure and oral air flow under different bleed and bite-block conditions.

    Science.gov (United States)

    Putnam, A H; Shelton, R L; Kastner, C U

    1986-03-01

    Intraoral pressures and oral flows were measured as normal talkers produced /p lambda/ and /si/ under experimental conditions that perturbed the usual aeromechanical production characteristics of the consonants. A translabial pressure-release device was used to bleed off intraoral pressure during /p/. Bite-blocks were used to open the anterior bite artificially during /s/. For /p/, intraoral pressure decreased and translabial air leakage increased as bleed orifice area increased. For /s/, flow increased as the area of sibilant constriction increased, but differential pressure across the /s/ oral constriction did not vary systematically with changes in its area. Flow on postconsonantal vowels /lambda/ and /i/ did not vary systematically across experimental conditions. The data imply that maintenance of perturbed intraoral pressure was more effective when compensatory options included opportunity for increased respiratory drive and structural adjustments at the place of consonant articulation rather than increased respiratory drive alone.

  4. Solar-Laundry - Solar-assisted air-conditioning of a laundry in Vienna; Solar-Laundry - Solare Klimatisierung einer Wiener Waescherei

    Energy Technology Data Exchange (ETDEWEB)

    Selke, T.; Neuhaeuser, M.; Pol, O. [arsenal research, Wien (Austria). Geschaeftsfeld Nachhaltige Energiesysteme

    2005-07-01

    Laundry enterprises produce immense amounts of waste heat due to the applied machines (washing machines, ironing machines, steam dolls). Consequently the indoor climate of the production area is dominated by high temperature and humidity values both in summer and in winter. Without any air-conditioning the climatic working conditions wouldn't be acceptable for the employees. The aim of the project >>Solar-Laundry<< is to design and implement a solar-assisted air-conditioning system in Vienna into the existing building services. By optimisation of the existing ventilation system and by the use of both solar heat and biomass heat the innovative air-conditioning plant demonstrates an ecological and energy-efficient technical application. The main project objectives are: 1. Significant improvement of indoor air comfort, 2. Installation of an innovative and sustainable energy system for air-conditioning with an acceptable surplus of investment, 3. Reduction of both primary energy consumption and energy costs compared to conventional air-conditioning systems. The participants in the >>Solar-Laundry<< project are: WienWork, TB-Holzinger Ingenieurgesellschaft m.b.H., pos architekten schneider ZT Keg, Oesterreichische Forschungs- und Pruefzentrum Arsenal GmbH. The solar-assisted air-conditioning system is the first plant in Vienna. The commissioning of the >>Solar-Laundry<< plant is scheduled for summer 2005. (orig.)

  5. Disponibilidad de agua-aire en sustratos para plantas Water-air availability in plant substrates

    Directory of Open Access Journals (Sweden)

    Lilia Beatriz Vence

    2008-12-01

    Full Text Available Las propiedades físicas de los sustratos especialmente las relacionadas con la disponibilidad de agua-aire para las raíces de las plantas son las más importantes dentro del estudio de estos materiales usados en cultivos en contenedores. Para un óptimo crecimiento de la planta un sustrato debe contener suficiente cantidad de agua y aire y ambos estar disponibles. A nivel mundial el estudio de las propiedades que determinan esta disponibilidad comenzó desde las ciencias del suelo y fue adaptándose a las características propias de la amplia gama de productos que pueden ser utilizados, surgiendo así variables y métodos de medida específicos para la caracterización física de sustratos. En la Argentina el estudio de sustratos para plantas constituye un área de conocimiento nueva y en desarrollo, por ello exige un trabajo interdisciplinario donde hay que concordar un lenguaje común de términos técnicos, la elección de los métodos analíticos de referencia específicos y una legislación actualizada para sustratos. Haciendo un estudio crítico de la gran cantidad de información al respecto que proviene de otros países se podrán adaptar a nuestra realidad y a nuestros materiales. En esta revisión se enumeran resumidamente los más importantes conceptos a tener en cuenta para la evaluación física de sustratos a fin de que puedan servir de base para una mejor comprensión y discusión del tema.The study of the physical properties of substrates for container plant production is very important because the water and air availability for plant roots is involved. A substrate must contain a sufficient amount of available water and air to produce an optimum plant growth and development. Worldwide, the study of the properties that determine the water and air availability started from soil sciences and has been evolving to the present existence of a great variety of products that can be used, concomitant with the identification of parameters

  6. [Bipolar ionisation of indoor air through ion generators mountable into inflow ventilation and conditioning].

    Science.gov (United States)

    Dudarev, A A; Spichkin, G L; Denisikhina, D M; Burtsev, S I

    2010-01-01

    Experimental studies and digital modelling of artificial indoor air ionisation through bipolar ionisers mountable into inflow ventilation and conditioning proved possible creation of continuous even bipolar ion background in indoor air, similar to the natural one.

  7. Application of Computer Model to Estimate the Consistency of Air Conditioning Systems Engineering

    Directory of Open Access Journals (Sweden)

    Amal El-Berry

    2013-04-01

    Full Text Available Reliability engineering is utilized to predict the performance and optimization of the design and maintenance of air conditioning systems. There are a number of failures associated with the conditioning systems. 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 are mainly due to a variety of problems with one or more components of an air conditioner or air conditioning system. To maintain the system forecasting for system failure rates are very important. The focus of this paper is the reliability of the air conditioning systems. The most common applied statistical distributions in reliability settings are the standard (2 parameter Weibull and Gamma distributions. Reliability estimations and predictions are used to evaluate, when the estimation of distributionsparameters is done. To estimate good operating condition in a building, the reliability of the air conditioning system that supplies conditioned air to the several companies’ departments is checked. This air conditioning system is divided into two systems, 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 - 45oF (4 - 7oC. 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, with the application of the Weibull and Gamma distributions it is 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 is studied. It is found that Weibull method has performed well for decision making .

  8. Control Techniques in Heating, Ventilating and Air Conditioning Systems

    Directory of Open Access Journals (Sweden)

    H. Mirinejad

    2008-01-01

    Full Text Available Problem statement: Heating, Ventilating and Air Conditioning (HVAC systems are among the main installations in residential, commercial and industrial buildings. The purpose of the HVAC systems is normally to provide a comfortable environment in terms of temperature, humidity and other environmental parameters for the occupants as well as to save energy. Achieving these objectives requires a suitable control system design. Approach: In this overview, thermal comfort level and ISO comfort field is introduced, followed by a review and comparison of the main existing control techniques used in HVAC systems to date. Results: The present overview shows that intelligent controllers which are based on the human sensation of thermal comfort have a better performance in providing thermal comfort as well as energy saving than the traditional controllers and those based on a model of the HVAC system. Conclusion: Such an overview provides an insight into current control methods in HVAC systems and can help scholars and HVAC learners to have the comprehensive information about a variety of control techniques in the field of HVAC and therefore to better design a proper controller for their work

  9. Assessing summertime urban air conditioning consumption in a semiarid environment

    Science.gov (United States)

    Salamanca, F.; Georgescu, M.; Mahalov, A.; Moustaoui, M.; Wang, M.; Svoma, B. M.

    2013-09-01

    Evaluation of built environment energy demand is necessary in light of global projections of urban expansion. Of particular concern are rapidly expanding urban areas in environments where consumption requirements for cooling are excessive. Here, we simulate urban air conditioning (AC) electric consumption for several extreme heat events during summertime over a semiarid metropolitan area with the Weather Research and Forecasting (WRF) model coupled to a multilayer building energy scheme. Observed total load values obtained from an electric utility company were split into two parts, one linked to meteorology (i.e., AC consumption) which was compared to WRF simulations, and another to human behavior. WRF-simulated non-dimensional AC consumption profiles compared favorably to diurnal observations in terms of both amplitude and timing. The hourly ratio of AC to total electricity consumption accounted for ˜53% of diurnally averaged total electric demand, ranging from ˜35% during early morning to ˜65% during evening hours. Our work highlights the importance of modeling AC electricity consumption and its role for the sustainable planning of future urban energy needs. Finally, the methodology presented in this article establishes a new energy consumption-modeling framework that can be applied to any urban environment where the use of AC systems is prevalent.

  10. Multivariate analysis comparing microbial air content of an air-conditioned building and a naturally ventilated building over one year

    Science.gov (United States)

    Parat, Sylvie; Perdrix, Alain; Fricker-Hidalgo, Hélène; Saude, Isabelle; Grillot, Renee; Baconnier, Pierre

    Heating, ventilation and air-conditioning (HVAC) may be responsible for the production and spread of airborne microorganisms in office buildings. In order to compare airborne microbiological flora in an air-conditioned building with that in a naturally ventilated building, eight sets of measurements were made over a 1-year period. Concurrently with other environmental measurements, air samples were collected in each building, from three offices and from the outdoor air, using the Andersen single-stage sampler. Three different media were used to culture fungi, staphylococci and mesophilic bacteria. Multivariate analysis revealed a group of offices more contaminated than others, and a marked seasonal variation in fungal concentrations. A comparison of mean levels of microorganisms measured in the two buildings showed that the air microbial content was significantly higher and more variable in the naturally ventilated building than in the air-conditioned building. Moreover, in the naturally ventilated building, the interior fungal content was strongly dependent on the outdoor content, while in the air-conditioned building fungal concentrations remained constant despite significant variations measured outside. This was confirmed by a statistical comparison of the correlation coefficients between indoor and outdoor concentrations. No difference was observed regarding gaseous pollutants and temperature, but relative humidity was significantly higher in the air-conditioned building. The effect of HVAC was to prevent the intake of outdoor particles and to dilute the indoor concentrations. These results are consistent with the presence of high-efficiency filters and a steam humidifier in the HVAC system under study.

  11. Integrated online condition monitoring system for nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Hashemian, Hashem M. [Analysis and Measurement Services Corporation, Knoxville, TN (United States). AMS Technology Center

    2010-09-15

    Online condition monitoring or online monitoring (OLM) uses data acquired while a nuclear power is operating to continuously assess the health of the plant's sensors, processes, and equipment; to measure the dynamic performance of the plant's process instrumentation; to verify in-situ the calibration of the process instrumentation; to detect blockages, voids, and leaks in the pressure sensing lines; to identify core flow anomalies; to extend the life of neutron detectors and other sensors; and to measure the vibration of reactor internals. Both the steady-state or DC output of plant sensors and their AC signal or noise output can be used to assess sensor health, depending on whether the application is monitoring a rapidly changing (e.g., core barrel motion) or a slowly changing (e.g., sensor calibration) process. The author has designed, developed, installed, and tested OLM systems (comprised of software/hardware-based data acquisition and data processing modules) that integrate low-frequency (1 mHz to 1 Hz) techniques such as RTD cross-calibration, pressure transmitter calibration monitoring, and equipment condition monitoring and high-frequency (1 Hz to 1 kHz) techniques such as the noise analysis technique. The author has demonstrated the noise analysis technique's effectiveness for measuring the dynamic response-time of pressure transmitters and their sensing lines; for performing predictive maintenance on reactor internals; for detecting core flow anomalies; and for extending neutron detector life. Integrated online condition monitoring systems can combine AC and DC data acquisition and signal processing techniques, can use data from existing process sensors during all modes of plant operation, including startup, normal operation, and shutdown; can be retrofitted into existing PWRs, BWRs, and other reactor types and will be integrated into next-generation plants. (orig.)

  12. Forest biomonitoring of the largest Slovene thermal power plant with respect to reduction of air pollution.

    Science.gov (United States)

    Al Sayegh Petkovšek, Samar

    2013-02-01

    The condition of the forest ecosystem in the vicinity of the largest Slovene power plant [the Šoštanj Thermal Power Plant (ŠTPP)] was monitored during the period 1991-2008 by determining the total concentration of sulphur, ascorbic acid and chlorophyll in Norway spruce needles. After 1995, the introduction of cleaning devices at the ŠTPP dramatically reduced the former extremely high SO(2) and dust emissions. The most significant findings of this comprehensive, long-duration survey are as follows: (1) the chosen parameters are suitable bioindicators of stress caused by air pollution in Norway spruce needles; they reflect both spatial and temporal variations in air pollution as well as the degree of efficiency of the cleaning devices; (2) observations show that the physiological condition of Norway spruce in northern Slovenia has significantly improved since 1995, when the first desulphurization device at ŠTPP was built, together with a reduction in the area influenced by pollution from ŠTPP; (3) metabolic processes in spruce needles react to air pollution according to the severity of the pollution and the length of exposure; exposure to high SO(2) ambient levels and/or spread over a long duration can damage the antioxidant defence mechanisms of spruce trees as well as diminishing the concentration of ascorbic acid; (4) a reduction in the exposure to air pollution improves the vitality of the trees (e.g. higher concentrations of total (a + b) chlorophyll), as well as restoring their defence capabilities as shown by higher concentrations of ascorbic acid; and (5) forest monitoring should be continued and focused on integrating the effects of multiple stressors, which can additionally affect a forest ecosystem.

  13. Application of FMEA-DEA (Failure Modes and Effect Analysis - Data Envelopment Analysis) to the air conditioning system of the control room a nuclear power plant; Aplicacao de FMEA-DEA ao sistema de ar condicionado da sala de controle de uma usina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa Junior, Gilberto Varanda

    2007-03-15

    This dissertation presents the FMEA-DEA analysis application to the air conditioning system of the control room of a nuclear power plant. After obtaining the failure modes, the index associated to the occurrence probability, the severity of the effects and the potential of detention, a priority order is established for the failure modes or deviations. This number is obtained by multiplying the three mentioned index that vary in a natural scale from 1 to 10, where the higher the index, the more critical the situation will be. In this work, it is intended to use a model based on the data envelopment analysis, DEA jointly with the FMEA, to identify the current efficiency of the system and which failure modes or deviations are considered more critical, and by means of the weights attributed for the mathematical modeling to identify which index are contributing more for these deviations. From this identification, improvements can be set, which may consider administrative changes, operator training and so on, thus adding value to the final product. (author)

  14. Plant leaves as indoor air passive samplers for volatile organic compounds (VOCs).

    Science.gov (United States)

    Wetzel, Todd A; Doucette, William J

    2015-03-01

    Volatile organic compounds (VOCs) enter indoor environments through internal and external sources. Indoor air concentrations of VOCs vary greatly but are generally higher than outdoors. Plants have been promoted as indoor air purifiers for decades, but reports of their effectiveness differ. However, while air-purifying applications may be questionable, the waxy cuticle coating on leaves may provide a simple, cost-effective approach to sampling indoor air for VOCs. To investigate the potential use of plants as indoor air VOC samplers, a static headspace approach was used to examine the relationship between leaf and air concentrations, leaf lipid contents and octanol-air partition coefficients (Koa) for six VOCs and four plant species. The relationship between leaf and air concentrations was further examined in an actual residence after the introduction of several chlorinated VOC emission sources. Leaf-air concentration factors (LACFs), calculated from linear regressions of the laboratory headspace data, were found to increase as the solvent extractable leaf lipid content and Koa value of the VOC increased. In the studies conducted in the residence, leaf concentrations paralleled the changing air concentrations, indicating a relatively rapid air to leaf VOC exchange. Overall, the data from the laboratory and residential studies illustrate the potential for plant leaves to be used as cost effective, real-time indoor air VOC samplers.

  15. Redox conditions and protein oxidation in plant mitochondria

    DEFF Research Database (Denmark)

    Møller, Ian Max; Kasimova, Marina R.; Krab, Klaas

    2005-01-01

    Redox conditions and protein oxidation in plant mitochondria NAD(P)H has a central position in respiratory metabolism. It is produced by a large number of enzymes, e.g. the Krebs cycle dehydrogenases, in the mitochondrial matrix and is oxidised by, amongst others, the respiratory chain. Most...... of this NAD(P)H appears to be bound to proteins, in fact free NAD(P)H – an important parameter in metabolic regulation - has never been observed in mitochondria. We have estimated free and bound NAD(P)H in isolated plant mitochondria under different metabolic conditions. The fluorescence spectra of free...... and bound NADH was determined and used to deconvolute fluorescence spectra of actively respiring mitochondria. Most of the mitochondrial NADH is bound in states 2 and 4. The amount of free NADH is lower but relatively constant even increasing a little in state 3 where it is about equal to bound NADH...

  16. Experimental investigation of integrated air purifying technology for bioaerosol removal and inactivation in central air-conditioning system

    Institute of Scientific and Technical Information of China (English)

    ZHENG Xiaohong; LIU Hongmin; YE Xiaojiang; LI Kejun; WANG Ruzhu; ZHAO Liping; Lisa. X. Xu; CHEN Yazhu; JIN Xinqiao; GU Bo; BAI Jingfeng

    2004-01-01

    In this research, high voltage static electricity and ultraviolet technologies were integrated to an air purifying device which can be used to trap and kill airborne bacteria and viruses in central air-conditioning systems. An experimental platform was built to mimic the central air system, in which the efficacy of the newly built device was examined. In addition to the standard physical and chemical tests, bacteriophages were used to simulate airborne viruses in the experimental system. The bacteriophage suspension was aerosolized into the air with ultrasonic wave atomization. The result showed that more than 86% removal efficiency of micro-particles (<10 micron in diameter) were removed after the device was in operation in a building and more than 95% of bacteriophages in the experimental system. It is concluded that the integrated air purifier is suitable for controlling air quality and preventing virus transmission through the central air system.

  17. Analysis of Phthalate Esters in Air, Soil and Plants in Plastic Film Greenhouse

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The phthalate esters such as DMP, DEP, DBP and DEHP in air, soil and plant samples in plastic film greenhouse were clean up with fine silica gel column and determined with HPLC. It was found that the concentrations of PEs in air and soil samples in plastic film greenhouse are much higher than those of contrast samples. But concentrations of PEs in plants in plastic film greenhouse are not remarkably affected by the pollution of air and soil.

  18. Morus nigra plant leaves as biomonitor for elemental air pollution monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Daud, M.; Khalid, N.; Waheed, S.; Wasim, M.; Arif, M.; Zaidi, J.H. [Pakistan Institute of Nuclear Science and Technology, Islamabad (Pakistan). Chemistry Div.

    2011-07-01

    The present paper deals with the determination of 36 elements in 120 leaf samples of Morus nigra plant to assess their potential as biomonitor for elemental air pollution monitoring. The elemental quantification was made by employing Instrumental Neutron Activation Analysis (INAA) and Atomic Absorption Spectrometric (AAS) techniques. The leaf samples were collected in spring, summer and winter seasons from various sites in Islamabad with different types of anthropogenic activities as well as from a reference site with minimum of such activities. Twenty four soil samples from the respective sites were also analyzed. The reliability of the adopted procedures was established by analyzing the certified reference materials, i.e., citrus leaves-1572 and soil-7, from NIST and IAEA, respectively, under identical experimental conditions and comparing the results obtained with the certified values which are in quite good agreement with each other. The enrichment values and Pollution Load Index (PLI) of the determined elements were computed and discussed accordingly. The elemental translocation from soil to roots, stem and leaves has also been studied by analyzing these parts of the same plant. The results indicated that the leaves of Morus nigra plant have promising potential to monitor the extent of air pollution in the vicinity of industrial as well as in high traffic areas. (orig.)

  19. Emission of bacteria and fungi in the air from wastewater treatment plants - a review.

    Science.gov (United States)

    Korzeniewska, Ewa

    2011-01-01

    An increase in global population, coupled with intensive development of industry and agriculture, has resulted in the generation and accumulation of large amounts of waste around the world. The spread of pathogenic microorganisms, endotoxins, odours and dust particles in the air is an inevitable consequence of waste production and waste management. Thus, the risk of infections associated with wastewater treatment plants (WWTPs) has become of a particular importance in recent decades. Sewage and unstable sludge contain various pathogens such as viruses, bacteria, and human and animal parasites. These microorganisms can be transmitted to the ambient air in wastewater droplets, which are generated during aeration or mechanical moving of the sewage. Bioaerosols generated during wastewater treatment may therefore pose a potential health hazard to workers of these plants or to habitants of their surroundings. The degree of human exposure to airborne bacteria, fungi, endotoxin and other allergens may vary significantly depending upon the type and the capacity of a plant, kind of the facilities, performed activities and meteorological conditions.

  20. 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

  1. Analysis of air-conditioning and drying processes using spreadsheet add-in for psychrometric data

    Directory of Open Access Journals (Sweden)

    E.O. Diemuodeke

    2010-01-01

    Full Text Available A spreadsheet add-in for the psychrometric data at any barometric pressure and in the air-conditioning and drying temperatureranges was developed using appropriate correlations. It was then used to simulate and analyse air-conditioning and dryingprocesses in the Microsoft Excel environment by exploiting its spreadsheet and graphic potentials. The package allowsone to determine the properties of humid air at any desired state, and to simulate and analyse air-conditioning as well asdrying processes. This, as a teaching tool, evokes the intellectual curiosity of students and enhances their interest and abilityin the thermodynamics of humid-air processes.

  2. Does urban vegetation mitigate air pollution in northern conditions?

    Science.gov (United States)

    Setälä, Heikki; Viippola, Viljami; Rantalainen, Anna-Lea; Pennanen, Arto; Yli-Pelkonen, Vesa

    2013-12-01

    It is generally accepted that urban vegetation improves air quality and thereby enhances the well-being of citizens. However, empirical evidence on the potential of urban trees to mitigate air pollution is meager, particularly in northern climates with a short growing season. We studied the ability of urban park/forest vegetation to remove air pollutants (NO2, anthropogenic VOCs and particle deposition) using passive samplers in two Finnish cities. Concentrations of each pollutant in August (summer; leaf-period) and March (winter, leaf-free period) were slightly but often insignificantly lower under tree canopies than in adjacent open areas, suggesting that the role of foliage in removing air pollutants is insignificant. Furthermore, vegetation-related environmental variables (canopy closure, number and size of trees, density of understorey vegetation) did not explain the variation in pollution concentrations. Our results suggest that the ability of urban vegetation to remove air pollutants is minor in northern climates.

  3. A Study on the Air Vent Valve of the Hydraulic Servo Actuator for Steam Control of Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Bum; Lee, Jong Jik [Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of)

    2016-06-15

    To produce adequate electricity in nuclear and thermal power plants, an optimal amount of steam should be supplied to a generator connected to high- and low-pressure steam turbines. A turbine output control device, which is a special steam valve employed to supply or interrupt the steam to the turbine, is operated using a hydraulic servo actuator. In power plants, the performance of servo actuators is degraded by the air generated from the hydraulic system, or causes frequent failures owing to an increase in the wear of the seal. This is due to the seal being burnt as generated heat using the produced compressed air. Some power plants have exhausted air using a fixed orifice, and thus they encounter power loss due to mass flow exhaust. Failures are generated in hydraulic pumps, electric motors, and valves, which are frequently operated. In this study, we perform modeling and analysis of the load-sensing air-exhaust valves, which can be passed through very fine flow under normal use conditions, and exhaust mass flow air at the beginning stage as with existing fixed orifices. Then, we propose a method to prevent failures due to the compressed air, and to ensure the control accuracy of hydraulic servo actuators.

  4. A Study of Interior Landscape Plants for Indoor Air Pollution Abatement

    Science.gov (United States)

    Wolverton, B. C.; Douglas, Willard L.; Bounds, Keith

    1989-01-01

    Previously, preliminary data on the ability of a group of common indoor plants to remove organic chemical from indoor air was presented. The group of plants chosen for this study was determined by joint agreement between NASA and the Associated Landscape Contractors of America. The chemicals chosen for study were benzene, trichloroethylene, and formaldehyde. The results show that plants can play a major role in removal of organic chemicals from indoor air.

  5. 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.

  6. Hazardous air pollutant testing at the LGTI coal gasification plant

    Energy Technology Data Exchange (ETDEWEB)

    Wetherold, R.G.; Williams, W.A.; Maxwell, D.P.; Mann, R.M.

    1995-06-01

    A comprehensive hazardous air pollutant test program was conducted in November 1994 at the Louisiana Gasification Technology, Inc. (LGTI), plant in Plaquemine, Louisiana. This program was sponsored by DOE/PETC, the Electric Power Research Institute (EPRI), and Destec Energy. In May of 1995, additional testing of the hot syngas stream was conducted at the LGTI facility under this same program. DOE/METC provided additional technical support for the hot gas testing effort. In this paper, the sampling and analytical methods used during the November and May test program are summarized. The hot gas testing is described in greater detail. In particular, the hot gas sampling probe and probe insertion/withdrawal system are discussed. The sampling probe was designed to collect particulate and extract gas samples at process temperature and pressure. The design of the probe system is described, and the operating procedures are summarized. The operation of the probe during the testing is discussed, and photographs of the testing are provided. In addition to the summaries and descriptions of the test methodologies, selected preliminary emissions results of the November sampling are included in the paper.

  7. Quantitative and enantioselective analysis of monoterpenes from plant chambers and in ambient air using SPME

    Directory of Open Access Journals (Sweden)

    N. Yassaa

    2010-11-01

    Full Text Available A headspace solid-phase microextraction (HS-SPME and gas chromatography/mass spectrometry (GC/MS system has been developed for quantifying enantiomeric and nonenantiomeric monoterpenes in plant chamber studies and ambient air. Performance of this system was checked using a capillary diffusion system to produce monoterpene standards. The adsorption efficiency, competitive adsorption and chromatographic peak resolution of monoterpene enantiomer pairs were compared for three SPME fibre coatings: 75 μm Carboxen-PDMS (CAR-PDMS, 50/30 μm divinylbenzene-carboxen-polydimethylsiloxane (DVB-CAR-PDMS and 65 μm divinylbenzene-polydimethylsiloxane (DVB-PDMS. Key parameters such as the linearity and reproducibility of the SPME system have been investigated in this work. The best compromise between the enantiomeric separation of monoterpenes and competitive adsorption of the isoprenoids on the solid SPME fibre coating was found for DVB-PDMS fibres. The optimum conditions using DVB-PDMS fibres were applied to measure the exchange rates of monoterpenes in the emission of Quercus ilex using a laboratory whole plant enclosure under light and dark conditions, as well as in ambient air. With 592 and 223 ng m−2 s−1 respectively, β-myrcene and limonene were the predominant monoterpenes in the emission of Q. ilex. These values were closely comparable to those obtained using a zNose and cartridge GC-FID systems.

  8. Quantitative and enantioselective analysis of monoterpenes from plant chambers and in ambient air using SPME

    Directory of Open Access Journals (Sweden)

    N. Yassaa

    2010-08-01

    Full Text Available A solid-phase microextraction (HS-SPME and gas chromatography/mass spectrometry (GC/MS system has been developed for quantifying enantiomeric and nonenantiomeric monoterpenes in plant chamber studies and ambient air. Performance of this system was checked using a capillary diffusion system to produce monoterpene standards. The adsorption efficiency, competitive adsorption and chromatographic peak resolution of monoterpene enantiomer pairs were compared for three SPME fibre coatings: 75 μm Carboxen-PDMS (CAR-PDMS, 50/30 μm, divinylbenzene-carboxen-polydimethylsiloxane (DVB-CAR-PDMS and 65 μm divinylbenzene-polydimethyl-siloxane (DVB-PDMS. Key parameters such as the linearity and reproducibility of the SPME system have been investigated in this work. The best compromise between the enantiomeric separation of monoterpenes and competitive adsorption of the isoprenoids on the solid SPME fibre coating was found for DVB-PDMS fibres. The optimum conditions using DVB-PDMS fibres were applied to measure the exchange rates of monoterpenes in the emission of Quercus ilex using a laboratory whole plant enclosure under light and dark conditions, as well as in ambient air. With 592 and 223 ng m−2 s−1, respectively, β-myrcene and limonene were the predominant monoterpenes in the emission of Q. ilex. These values were closely comparable to those obtained using a zNose and cartridge GC-FID systems.

  9. Computerized Simulation of Automotive Air-Conditioning System: Development of Mathematical Model and Its Validation

    Directory of Open Access Journals (Sweden)

    Haslinda Mohamed Kamar

    2012-03-01

    Full Text Available A semi-empirical model for simulating thermal and energy performance of an automotive air-conditioning (AAC system in passenger vehicles has been developed. The model consists of two sections, namely empirical evaporator correlations and dynamic load simulation. The correlations used consider sensible and latent heat transfer performance of the evaporator coil. The correlations were obtained from the experimental data of actual air conditioning system for a compact size passenger car. The sensible heat transfer correlation relates the evaporator air off dry-bulb temperature to inlet air dry-bulb temperature, humidity ratio, evaporator air velocity, condenser inlet air dry-bulb temperature, condenser air velocity and compressor speed. The latent heat transfer correlation relates the coil air-off humidity ratio to the same six independent variables. The dynamic load simulation model was developed based on the z-transfer function method with a one-minute time step. The cooling load calculations were performed using heat gain weighting factors. Heat extraction rate and cabin air dry-bulb temperature calculations were carried out using air temperature weighting factors. The empirical evaporator sensible and latent heat transfer correlations were embedded in the loads calculation program to enable the determination of evaporator inlet and outlet air conditions, the cabin air temperature and relative humidity. Comparisons with road test data indicated that the program was capable of predicting the performance of the automotive air-conditioning system with reasonable accuracy.

  10. 75 FR 6338 - Protection of Stratospheric Ozone: New Substitute in the Motor Vehicle Air Conditioning Sector...

    Science.gov (United States)

    2010-02-09

    ... to use conditions as a substitute for CFC-12 in motor vehicle air conditioning. The proposed... AGENCY 40 CFR Part 82 Protection of Stratospheric Ozone: New Substitute in the Motor Vehicle Air Conditioning Sector Under the Significant New Alternatives Policy (SNAP) Program AGENCY: Environmental...

  11. Poaceae pollen in the air depending on the thermal conditions

    Science.gov (United States)

    Myszkowska, Dorota

    2014-07-01

    The relationship between the meteorological elements, especially the thermal conditions and the Poaceae pollen appearance in the air, were analysed as a basis to construct a useful model predicting the grass season start. Poaceae pollen concentrations were monitored in 1991-2012 in Kraków using the volumetric method. Cumulative temperature and effective cumulative temperature significantly influenced the season start in this period. The strongest correlation was seen as the sum of mean daily temperature amplitudes from April 1 to April 14, with mean daily temperature >15 °C and effective cumulative temperature >3 °C during that period. The proposed model, based on multiple regression, explained 57 % of variation of the Poaceae season starts in 1991-2010. When cumulative mean daily temperature increased by 10 °C, the season start was accelerated by 1 day. The input of the interaction between these two independent variables into the factor regression model caused the increase in goodness of model fitting. In 2011 the season started 5 days earlier in comparison with the predicted value, while in 2012 the season start was observed 2 days later compared to the predicted day. Depending on the value of mean daily temperature from March 18th to the 31st and the sum of mean daily temperature amplitudes from April 1st to the 14th, the grass pollen seasons were divided into five groups referring to the time of season start occurrence, whereby the early and moderate season starts were the most frequent in the studied period and they were especially related to mean daily temperature in the second half of March.

  12. 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.

  13. Cooling Performance Characteristics on Mobile Air-Conditioning System for Hybrid Electric Vehicles

    OpenAIRE

    Ho-Seong Lee; Moo-Yeon Lee

    2013-01-01

    This study investigates the cooling performance characteristics of the mobile air-conditioning system using R744 (CO2) for the hybrid electric vehicle as an alternative to both the R-134a and the conventional air-conditioning system. The developed air-conditioning system is operated with an electric driven compressor in the battery driving mode and a belt driven compressor in the engine driving mode. The cooling performance characteristics of the developed system have been analyzed by experim...

  14. PRINCIPLES OF SAFETY MANAGEMENT OF AIR TRAFFIC FLOWS AND CAPACITY UNDER UNCERTAINTY CONDITIONS

    Directory of Open Access Journals (Sweden)

    Wang Bo

    2016-11-01

    Full Text Available Purpose: The aim of this study is to investigate the general principles of safety and capacity management in Aeronautical systems regarding air traffic flows operations under uncertainty conditions. In this work the theoretical framework assessing at the same time both the uncertainty model and flight plans model are proposed. Methods: To study features of safety of air traffic flows and capacity under uncertainty conditions were built the original probabilistic models including Bayesian Network for flight plan and air traffic control sector model based on Poisson Binomial Distribution. Results: We obtained models for safety management of air traffic flows and capacity under uncertainty conditions. We discussed appropriate approach for estimating the parameters of safety of air traffic flows and capacity under uncertainty and Markovian uncertainty model for the flight plan. Discussion: We developed the Bayesian Network for flight plan and air traffic control sector models for safety management of air traffic flows and capacity under uncertainty conditions.

  15. Human requirements in future air-conditioned environments

    DEFF Research Database (Denmark)

    Fanger, Povl Ole

    2002-01-01

    in the built environment: better indoor air quality increases productivity and decreases SBS symptoms; unnecessary indoor pollution sources should be avoided; the air should be served cool and dry to the occupants; personalized ventilation, i.e. small amounts of clean air, should be provided gently, close...... though existing standards and guidelines are met. A paradigm shift from rather mediocre to excellent indoor environments is foreseen in buildings in the 21st century. Based on existing information and on new research results, five principles are suggested as elements behind a new philosophy of excellence...

  16. Human requirements in future air-conditioned environments

    DEFF Research Database (Denmark)

    Fanger, Povl Ole

    1999-01-01

    : better indoor air quality increases productivity and decreases SBS symptoms; unnecessary indoor pollution sources should be avoided; the air should be served cool and dry to the occupants; small amounts of clean air should be served gently, close to the breathing zone of each individual; individual......, even though existing standards and guidelines are met. A paradigm shift from rather mediocre to excellent indoor environments is foreseen in the 21st century. Based on existing information and on new research results, five principles are suggested as elements behind a new philosophy of excellence...

  17. Plant cover, soil temperature, freeze, water stress, and evapotranspiration conditions. [south Texas

    Science.gov (United States)

    Wiegand, C. L.; Nixon, P. R.; Gausman, H. W.; Namken, L. N.; Leamer, R. W.; Richardson, A. J. (Principal Investigator)

    1981-01-01

    Emissive and reflective data for 10 days, and IR data for 6 nights in south Texas scenes were analyzed after procedures were developed for removing cloud-affected data. HCMM radiometric temperatures were: within 2 C of dewpoint temperatures on nights when air temperature approached dewpoint temperatures; significantly correlated with variables important in evapotranspiration; and, related to freeze severity and planting depth soil temperatures. Vegetation greenness indexes calculated from visible and reflective IR bands of NOAA-6 to -9 meteorological satellites will be useful in the AgRISTARS program for seasonal crop development, crop condition, and drought applications.

  18. Air conditioning design temperature - a new proposal; Temperatura de projeto para condicionamento de ar - uma nova proposta

    Energy Technology Data Exchange (ETDEWEB)

    Camargo, Jose R.; Cardoso, Sebastiao [Universidade de Taubate, SP (Brazil). Dept. de Engenharia Mecanica]. E-mails: rui@engenh.mec.unitau.br; cardoso@prppg.unitau.br; Travelho, Jeronimo S. [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil)]. E-mail: jeff@lac.inpe.br

    2000-07-01

    ABNT - Associacao Brasileira de Normas Tecnicas (Brazilian Association for Technical Standards) - establishes, in NBR-6401, Table 1 (Interior Design Conditions), the dry-bulb summer temperature and the relative humidity to be used in air conditioning design. In thermal comfort plant for residences, hotels, offices and schools these values are, respectively, 23 deg C to 25 deg C and 40% to 60% rh. These data are in accordance with what is recommended by ASHRAE, which was established as a model for North America. This paper presents a new proposal to air conditioning design temperature that takes into consideration Brazilian climatological conditions. The method, named 'effective temperature distribution', compares the maximum recommended effective temperature for each region with dry-bulb temperatures and effective temperatures plotted in a single diagram. This diagram may be used in energetic planning to minimize the use of electric energy for air conditioning. It concludes that the method allows an accuracy analysis about both the temperature levels and the periods of utilization of the air conditioning systems. (author)

  19. Impact of air conditioning system operation on increasing gases emissions from automobile

    Science.gov (United States)

    Burciu, S. M.; Coman, G.

    2016-08-01

    The paper presents a study concerning the influence of air conditioning system operation on the increase of gases emissions from cars. The study focuses on urban operating regimes of the automobile, regimes when the engines have low loads or are operating at idling. Are presented graphically the variations of pollution emissions (CO, CO2, HC) depending of engine speed and the load on air conditioning system. Additionally are presented, injection duration, throttle position, the mechanical power required by the compressor of air conditioning system and the refrigerant pressure variation on the discharge path, according to the stage of charging of the air conditioning system.

  20. [Design, equipment, and management for air conditioning in operating room].

    Science.gov (United States)

    Fuji, Kumiko; Mizuno, Ju

    2011-11-01

    In order to maintain air cleanliness in the operating room (OR) permanently, air exchange rate in the OR should be more than 15 times x hr(-1), the laminar air flow should be kept, and the numbers of the persons in the OR and the numbers of opening and closing OR door should be limited. High efficiency particulate air (HEPA) filter is effective in collection and removal of airborne microbes, and is used in the biological clean room. We need to design, equip, and manage the OR environment according to Guideline for Design and Operation of Hospital HVAC Systems HEAS-02-2004 established by Healthcare Engineering Association of Japan and Guideline for Prevention of Surgical Site Infection (SSI) established by the Center for Disease Control and Prevention (CDC) in the USA.

  1. COMPOSITION CHANGES IN REFRIGERANT BLENDS FOR AUTOMOTIVE AIR CONDITIONING

    Science.gov (United States)

    Three refrigerant blends used to replace CFC-12 in automotive air conditioners were evaluated for composition changes due to typical servicing and leakage. When recommended service procedures were followed, changes in blend compositions were relatively small. Small changes in b...

  2. 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.

  3. Research of the Temperature and Humidity Processes in the Air Conditioning Apparatus Varying Air Ion Concentration

    Directory of Open Access Journals (Sweden)

    Marchenko V. G.

    2015-12-01

    Full Text Available To create comfortable conveniences for people in the room, we have to process the indoor air in the AC apparatus. Depending on given air parameters in the room, the air processing comprises the next steps: heating, cooling, wetting, drying. Except the compliance of the temperature and humidity parameters of air, we must control its ionic composition. Thereby, the experimental analysis of the air preparing in the AC apparatus is given in this article. Thank to that analysis, we can estimate the ionic and deionic impact on the air space in the specific processes of the air preparing. According to the results of experiments, we have identified, that the air temperature varying does not have significant effect on the ionic concentration. The ionic increasing after electric heater is not associated with air temperature. It is the consequence of the electron extrication from the surface of the heating element. Reducing ion moving the high air humidity decreases the concentration of the lightweight ions. The increasing of the ions in the spray-type air washers is explained by ballo-electric effect of spraying water drops, but not the air humidity rising.

  4. Air Filtration as Protection against Fouling of Ventilation and Air Conditioning Units

    DEFF Research Database (Denmark)

    Bekö, Gabriel; Lajčíková, Ariana

    2005-01-01

    Currently, air filters are one of the most critical components of air treatment systems as they decontaminate the air delivered to living space. During the operation, however, the level of harmful surface deposits increases, and at certain times, an uncleaned filter can itself become a source...

  5. 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.

  6. New model concepts for dynamic plant uptake and mass flux estimates in the soil-plant-air system

    DEFF Research Database (Denmark)

    Rein, Arno; Bauer-Gottwein, Peter; Trapp, Stefan

    2010-01-01

    Plants significantly influence contaminant transport and fate. Important processes are uptake of soil and groundwater contaminants, as well as biodegradation in plants and their root zones. Models for the prediction of chemical uptake into plants are required for the setup of mass balances...... in environmental systems at different scales. Feedback mechanisms between plants and hydrological systems can play an important role. However, they have received little attention to date. Here, a new model concept for dynamic plant uptake models applying analytical matrix solutions is presented, which can...... be coupled to groundwater transport simulation tools. Exemplary simulations of plant uptake were carried out in order to estimate chemical concentrations in the soil-plant-air system and the influence of plants on contaminant mass fluxes from soil to groundwater....

  7. Factors affecting xylene-contaminated air removal by the ornamental plant Zamioculcas zamiifolia.

    Science.gov (United States)

    Sriprapat, Wararat; Boraphech, Phattara; Thiravetyan, Paitip

    2014-02-01

    Fifteen plant species-Alternanthera bettzickiana, Drimiopsis botryoides, Aloe vera, Chlorophytum comosum, Aglaonema commutatum, Cordyline fruticosa, Philodendron martianum, Sansevieria hyacinthoides, Aglaonema rotundum, Fittonia albivenis, Muehlenbeckia platyclada, Tradescantia spathacea, Guzmania lingulata, Zamioculcas zamiifolia, and Cyperus alternifolius-were evaluated for the removal efficiency of xylene from contaminated air. Among the test plants, Z. zamiifolia showed the highest xylene removal efficiency. Xylene was toxic to Z. zamiifolia with an LC50 of 3,464 ppm. Higher concentrations of xylene exhibited damage symptoms, including leaf tips turning yellow, holonecrosis, and hydrosis. TEM images showed that a low concentration of xylene vapors caused minor changes in the chloroplast, while a high concentration caused swollen chloroplasts and damage. The effect of photosynthetic types on xylene removal efficiency suggests that a mixture of Z. zamiifolia, S. hyacinthoides, and A. commutatum which represent facultative CAM, CAM, and C3 plants, is the most suitable system for xylene removal. Therefore, for maximum improvement in removing xylene volatile compounds under various conditions, multiple species are needed. The effect of a plant's total leaf area on xylene removal indicates that at lower concentrations of xylene, a small leaf area might be as efficient as a large leaf area.

  8. Uptake of toluene and ethylbenzene by plants: removal of volatile indoor air contaminants.

    Science.gov (United States)

    Sriprapat, Wararat; Suksabye, Parinda; Areephak, Sirintip; Klantup, Polawat; Waraha, Atcharaphan; Sawattan, Anuchit; Thiravetyan, Paitip

    2014-04-01

    Air borne uptake of toluene and ethylbenzene by twelve plant species was examined. Of the twelve plant species examined, the highest toluene removal was found in Sansevieria trifasciata, while the ethylbenzene removal from air was with Chlorophytum comosum. Toluene and ethylbenzene can penetrate the plant׳s cuticle. However, the removal rates do not appear to be correlated with numbers of stomata per plant. It was found that wax of S. trifasciata and Sansevieria hyacinthoides had greater absorption of toluene and ethylbenzene, and it contained high hexadecanoic acid. Hexadecanoic acid might be involved in toluene and ethylbenzene adsorption by cuticles wax of plants. Chlorophyll fluorescence analysis or the potential quantum yield of PSII (Fv/Fm) in toluene exposed plants showed no significant differences between the control and the treated plants, whereas plants exposed to ethylbenzene showed significant differences or those parameters, specifically in Dracaena deremensis (Lemon lime), Dracaena sanderiana, Kalanchoe blossfeldiana, and Cordyline fruticosa. The Fv/Fm ratio can give insight into the ability of plants to tolerate (indoor) air pollution by volatile organic chemicals (VOC). This index can be used for identification of suitable plants for treating/sequestering VOCs in contaminated air.

  9. Does the soil-air-plant pathway contribute to the PCB contamination of apples from allotment gardens?

    Energy Technology Data Exchange (ETDEWEB)

    Krauss, M.; Moering, J.; Amelung, W. [Dept. of Soil Science, Inst. of Ecology, Berlin Univ. of Tech. (Germany)

    2004-09-15

    The presence of persistent organic pollutants (POPs) like PCBs in plants poses a risk to humans and animals as it determines an exposure through the terrestrial food chain. A number of studies have shown that the transfer from the atmosphere is the dominant pathway for an uptake of POPs by aboveground parts of plants, in which dry gaseous as well as wet and dry particulate deposition are involved. The relative contribution of the different pathways to the overall deposition depends strongly on the physical-chemical properties of the compounds, but also on microclimatic conditions and characteristics of the plant, which both contribute to diffusive resistance at the its surface. In contrast, root uptake and translocation in the shoot is probably much less important for these highly hydrophobic compounds, although there are contradicting results in the literature. While the air-plant distribution of POPs received increasing attention, the importance of the soilair- plant pathway has rarely been studied. It is not known whether the volatilisation of POPs from contaminated soils and subsequent deposition to plants may be a significant source compared to ''background'' deposition in the field, as well as a deposition of contaminated soil dust raised by wind or rain splash. Particularly the latter pathway can hardly be assessed under exposure chamber conditions; instead a field study is required despite the increased overall complexity, which renders process identification more difficult. The objective of our study was to assess whether the local soil contamination (soil-air-plant pathway) could contribute to the PCB contamination of apples (Malus domestica Borkh.) at an allotment garden site additionally to background deposition (air-plant pathway).

  10. 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

  11. Residential air-conditioning and climate change: voices of the vulnerable.

    Science.gov (United States)

    Farbotko, Carol; Waitt, Gordon

    2011-12-01

    Decreasing the risk of heat-stress is an imperative in health promotion, and is widely accepted as necessary for successful adaptation to climate change. Less well understood are the vulnerabilities that air-conditioning use exacerbates, and conversely, the need for the promotion of alternative strategies for coping with heat wave conditions. This paper considers these issues with a focus on the role of air-conditioning in the everyday life of elderly public housing tenants living alone, a sector of the population that has been identified as being at high risk of suffering heat stress. A vulnerability analysis of domestic air-conditioning use, drawing on literature and policy on air-conditioning practices and ethnographic research with households. Residential air-conditioning exacerbated existing inequities. Case studies of two specifically selected low-income elderly single person households revealed that such households were unlikely to be able to afford this 'solution' to increasing exposure to heat waves in the absence of energy subsidies. Residential air-conditioning use during heat waves caused unintended side-effects, such as system-wide blackouts, which, in turn, led to escalating electricity costs as power companies responded by upgrading infrastructure to cope with periods of excess demand. Air-conditioning also contributed to emissions that cause climate change. Residential air-conditioning is a potentially maladaptive technology for reducing the risk of heat stress.

  12. The system of thermoelectric air conditioning based on permeable thermoelements

    Directory of Open Access Journals (Sweden)

    Cherkez R. G.

    2009-04-01

    Full Text Available There is thermoelectric air conditioner unit on the basis of permeable cooling thermoelements presented. In thermoelectric air conditioner unit the thermoelectric effects and the Joule–Thomson effect have been used for the air stream cooling. There have been described the method of temperature distribution analysis, the determinations of energy conversion power characteristics and design style of permeable thermoelement with maximum coefficient of performance described. The results of computer analysis concerning the application of the thermoelement legs material on the basis of Bi2Te3 have shown the possibility of coefficient of performance increase by a factor of 1,6—1,7 as compared with conventional thermoelectric systems.

  13. Impacts of Photovoltaic Power Plant Sitings and Distributed Solar Panels on Meteorology and Air Quality in Central California

    Science.gov (United States)

    Bastien, L. A.; Jin, L.; Brown, N. J.

    2012-12-01

    California's electric utility companies are required to use renewable energy to produce 20% of their power by 2010 and 33% by 2020. A main source of the power will be solar energy because photovoltaic technologies have advanced so much that large scale installations are being built and will be built in the future with even greater capacity. Rather than being a large emission source, these plants affect the ambient environment through albedo changes and by emission reductions associated with not burning fossil fuels to generate the same amount of electricity. Like conventional power plants, their impact on local meteorology and air quality depends on the specific technology, ambient atmospheric conditions, and the spatial location of the plant. Also, as solar panels on commercial and residential rooftops become even more common, the effect of distributed photovoltaic panels on meteorology and air quality is likely to become significant. In this study, we use the Weather Research and Forecasting (WRF) model and the Community Multiscale Air Quality (CMAQ) model at high resolution of 4 km x 4 km over several 5-day high-ozone episodes of the summer 2000 to assess the impact of photovoltaic panels on meteorology and air quality in Central California. We investigate the effect of locating a 1.0 Giga watt solar plant in different locations and the effect of distributed rooftop photovoltaic panels in major Californian cities, with a focus on peak and 8-hour average ozone and 24-hour average PM2.5.

  14. The effect of air-conditioning parameters and deposition dust on microbial growth in supply air ducts

    Energy Technology Data Exchange (ETDEWEB)

    Li, Angui; Liu, Zhijian; Zhu, Xiaobin; Liu, Ying [School of Environmental and Municipal Engineering, Xi' an University of Architecture and Technology, Xi' an, Shannxi 710055 (China); Wang, Qingqin [China Academy of Building Research, Beijing 100013 (China)

    2010-04-15

    To investigate the effect of air-conditioning parameters (including temperature, relative humidity and air velocity) and deposition dust on microbial growth in supply air duct, a complete test facility according to ASHRAE Standard 62.1-2007 was constructed. A series of experiments for testing microbial concentration (including bacteria and fungus) were conducted under different working conditions (such as different temperatures and relative humidity). The air velocity was constantly kept at 2.0 m/s. Orthogonal design was employed for the analysis of test data. The results indicated that air velocity attenuation down the direction of the supply air affected dust distribution at the bottom of duct, to some extent, and the number of microorganisms was positively correlated with the quantity of dust. In the range of temperature 22-32 C and relative humidity (RH) 40-90%, microbial growth significantly accelerated with higher temperature and RH increasing. The organic compounds composing the dust also had great impact on microbial growth. The basic researches are contributed to control the growth of microorganism and improve the indoor microenvironment in the air-conditioning room. (author)

  15. Air pollution in surrounding environment of Sasa tailing dam – ambient air, plant dust and ceiling dust

    OpenAIRE

    Krstev, Boris; Krstev, Aleksandar; Golomeov, Blagoj; Golomeova, Mirjana; Zendelska, Afrodita; Danevski, Tome; Fidancev, Boris

    2013-01-01

    The current and recent activities in the lead-zinc Sasa mine or copper Bucim mine and flotation of galena and sphalerite or chalcopyrite, producing metals for market, are reason for possible troubles from tailing dam-pond and surrounding river, ambient air and plant or ceiling dust. This appearance is significant for the surrounding environment, but legislative and ecological law directive limited the quantity of these. In this paper will be present results of investigations from plant ...

  16. Air Filtration as Protection against Fouling of Ventilation and Air Conditioning Units

    DEFF Research Database (Denmark)

    Bekö, Gabriel; Lajčíková, Ariana

    2005-01-01

    Currently, air filters are one of the most critical components of air treatment systems as they decontaminate the air delivered to living space. During the operation, however, the level of harmful surface deposits increases, and at certain times, an uncleaned filter can itself become a source...... of undesirable contaminents influencing negatively the IAQ of a living space. This is the phenomenon that has been a subject of the current research. The article presents a new, alternative view on indoor air contaminents and filtration requirements. It describes alternative means of filtration and assesses...... issues of inadequate maintenance and/or long term use of applied air filters. An experimental method of evealuating the air quality by means of chemical analysis and state-of-the-art spectrometer is also described....

  17. [Sanitary and epidemiological evaluation of the ventilation and air-conditioning systems of public buildings].

    Science.gov (United States)

    Dvorianov, V V

    2012-01-01

    The microbial contamination of ventilation and air conditioning systems was examined in the administrative buildings. The author proposes a set of indicators, methods for determining the scope of investigations, as well as sampling tactics and criteria for evaluating the microbial contamination of the ventilation and air-conditioning systems. The content of yeasts and molds in the delivered air has been found to be of importance for evaluating the sanitary-and epidemiological state of ventilation systems.

  18. 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.

  19. Exchange of nitrogen dioxide (NO2) between plants and the atmosphere under laboratory and field conditions

    Science.gov (United States)

    Breuninger, C.; Meixner, F. X.; Thielmann, A.; Kuhn, U.; Dindorf, T.; Kesselmeier, J.

    2012-04-01

    Nitric oxide (NO), nitrogen dioxide (NO2), often denoted as nitrogen oxides (NOx), and ozone (O3) are considered as most important compounds in atmospheric chemistry. In remote areas NOx concentration is related to biological activities of soils and vegetation. The emitted NOx will not entirely be subject of long range transport through the atmosphere. Aside oxidation of NO2 by the OH radical (forming HNO3), a considerable part of it is removed from the atmosphere through the uptake of NO2 by plants. The exchange depends on stomatal activity and on NO2 concentrations in ambient air. It is known that NO2 uptake by plants represents a large NO2 sink, but the magnitude and the NO2 compensation point concentration are still under discussion. Our dynamic chamber system allows exchange measurements of NO2 under field conditions (uncontrolled) as well as studies under controlled laboratory conditions including fumigation experiments. For NO2 detection we used a highly NO2 specific blue light converter (photolytic converter) with subsequent chemiluminescence analysis of the generated NO. Furthermore, as the exchange of NO2 is a complex interaction of transport, chemistry and plant physiology, in our field experiments we determined fluxes of NO, NO2, O3, CO2 and H2O. For a better knowledge of compensation point values for the bi-directional NO2 exchange we investigated a primary representative of conifers, Picea abies, under field and laboratory conditions, and re-analyzed older field data of the deciduous tree Quercus robur.

  20. Humid Air Turbine as a Primary Link of a Coal-Fired Steam Power Plant

    Directory of Open Access Journals (Sweden)

    Jan T. Szargut

    2000-06-01

    Full Text Available Outlet gases of the humid air turbine (having a temperature of about 125 oC and great content of steam can be used for the preheating of feed water of the steam power plant fueled with coal. So the efficiency of the plant can be increased and its ecological indices can be improved. The attainable incremental efficiency of the humid air turbine and the increased efficiency of the combined plant has been determined for three variants of the repowering of an existing steam power plant. The variant presented in Figure 4 is recommended for practical application.

  1. Sulfur containing air pollutants and their effects on plant metabolism

    NARCIS (Netherlands)

    De Kok, L.J.; Maas, F.M.; Stulen, I.; Kuiper, P.J.C.; Mathy, P.

    1988-01-01

    H2S and SO2 affected plant yield at relative low levels without causing visible injury. In general H2S was more toxic than SO2. Short-term exposure (24 to 48 h) of plants to the pollutants affected sulfur, nitrogen and energy metabolism. Both exposure of plants to H2S and SO2 resulted in an accumula

  2. Sulfur containing air pollutants and their effects on plant metabolism

    NARCIS (Netherlands)

    De Kok, L.J.; Maas, F.M.; Stulen, I.; Kuiper, P.J.C.; Mathy, P.

    1988-01-01

    H2S and SO2 affected plant yield at relative low levels without causing visible injury. In general H2S was more toxic than SO2. Short-term exposure (24 to 48 h) of plants to the pollutants affected sulfur, nitrogen and energy metabolism. Both exposure of plants to H2S and SO2 resulted in an

  3. 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…

  4. Automotive Air Conditioning and Heating; Automotive Mechanics (Advanced): 9047.04.

    Science.gov (United States)

    Dade County Public Schools, Miami, FL.

    This document presents an outline for a 135-hour course designed to provide the student with all the foundations necessary to become employable in the automotive air conditioning and heating trade. The course of study includes an orientation to the world of work, the elementary physics of air conditioning and heating, and laboratory experiments…

  5. Air-Puff Conditioning Audiometry: Extending Its Applicability with Multiply Handicapped Individuals.

    Science.gov (United States)

    Lancioni, G. E.; And Others

    1990-01-01

    This study examined the use of air-puff conditioning audiometry in the hearing assessment of 12 multiply handicapped (including severe/profound mental retardation) subjects, ages 9-32. Ten subjects reached criterion conditioning and then completed the hearing assessment with the air-puff procedure while one reached criterion with a modified…

  6. 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…

  7. Criterion-Referenced Test (CRT) Items for Air Conditioning, Heating and Refrigeration.

    Science.gov (United States)

    Davis, Diane, Ed.

    These criterion-referenced test (CRT) items for air conditioning, heating, and refrigeration are keyed to the Missouri Air Conditioning, Heating, and Refrigeration Competency Profile. The items are designed to work with both the Vocational Instructional Management System and Vocational Administrative Management System. For word processing and…

  8. 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.

  9. Retrofitting Air Conditioning and Duct Systems in Hot, Dry Climates

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, C.; Aldrich, R.; Arena, L.

    2012-07-01

    This technical report describes CARB's work with Clark County Community Resources Division in Las Vegas, Nevada, to optimize procedures for upgrading cooling systems on existing homes in the area to implement health, safety, and energy improvements. Detailed monitoring of five AC systems showed that three of the five systems met or exceeded air flow rate goals.

  10. Retrofitting Air Conditioning and Duct Systems in Hot, Dry Climates

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, Carl [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Aldrich, Robb [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Arena, Lois [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States)

    2012-07-01

    This technical report describes CARB's work with Clark County Community Resources Division in Las Vegas, Nevada, to optimize procedures for upgrading cooling systems on existing homes in the area to implement health, safety, and energy improvements. Detailed monitoring of five AC systems showed that three of the five systems met or exceeded air flow rate goals.

  11. Thin layer convective air drying of wild edible plant (Allium roseum) leaves: experimental kinetics, modeling and quality.

    Science.gov (United States)

    Ben Haj Said, Leila; Najjaa, Hanen; Farhat, Abdelhamid; Neffati, Mohamed; Bellagha, Sihem

    2015-06-01

    The present study deals with the valorization of an edible spontaneous plant of the Tunisian arid areas: Allium roseum. This plant is traditionally used for therapeutic and culinary uses. Thin-layer drying behavior of Allium roseum leaves was investigated at 40, 50 and 60 °C drying air temperatures and 1 and l.5 m/s air velocity, in a convective dryer. The increase in air temperature significantly affected the moisture loss and reduced the drying time while air velocity was an insignificant factor during drying of Allium roseum leaves. Five models selected from the literature were found to satisfactorily describe drying kinetics of Allium roseum leaves for all tested drying conditions. Drying data were analyzed to obtain moisture diffusivity values. During the falling rate-drying period, moisture transfer from Allium roseum leaves was described by applying the Fick's diffusion model. Moisture diffusivity varied from 2.55 × 10(-12) to 8.83 × 10(-12) m(2)/s and increased with air temperature. Activation energy during convective drying was calculated using an exponential expression based on Arrhenius equation and ranged between 46.80 and 52.68 kJ/mol. All sulfur compounds detected in the fresh leaves were detected in the dried leaves. Convective air drying preserved the sulfur compounds potential formation.

  12. Condition telemonitoring and diagnosis of power plants using web technology

    Energy Technology Data Exchange (ETDEWEB)

    Kunze, U. [Siemens AG, Erlangen (Germany). Power Generation

    2003-07-01

    The monitoring and diagnostic systems currently installed in power plants generally supply information for control room displays and for on-site personnel. Telemonitoring is also frequently used. In this case, relevant diagnostic data are transmitted remotely to a special laboratory for analysis using highly specialized equipment and software. The appearance of the terms 'Monitoring' and 'Diagnosis' alongside the term 'Web Technology' in the title of this paper does not mean that remote access to diagnostic systems over the Internet is being presented here as a simple extension of the existing situation. Condition telemonitoring and diagnosis based on Web technology is a new departure in diagnostic system design philosophy. It is the technology used to integrate diagnostic systems into a customer's IT infrastructure (Intranet or Internet). Siemens has started to use Web-based condition telemonitoring and diagnosis in some power plants (nuclear and fossil-fueled) to provide a global source of specialist support.

  13. Application of Fuzzy Comprehensive Evaluation to Air-conditioning Competitive Power Analysis

    Institute of Scientific and Technical Information of China (English)

    LU Congda; LIU Gaojin; JIANG Shaofei; LV Chaoqun

    2006-01-01

    As the conceptual design of air-conditioning is done using the theory of Quality Function Deployment (QFD), customer requirements should be understood and the product competitive power be analyzed as exactly as possible for new product designing. Lots of information in the process of this research is fuzzy and uncertain, but traditional QFD can not deal with it well. Fuzzy theory can solve the problem. So a fuzzy model for analyzing product competitive power is formulated in this paper to improve traditional QFD, after that it is applied to analyze air-conditioning competitive power. When air-conditioning competitive power is analyzed using this model, firstly the importance weight of the customer requirements of air-conditioning is determined using the Analytic Hierarchy Process (AHP) weighting process, then air-conditioning competitive power is evaluated using fuzzy comprehensive evaluation. It is proved that the model is feasible and has good applicability.

  14. Floristic summary of North American plant species in the air pollution literature

    Science.gov (United States)

    Bennett, J.P.; Yunus, M.; Singh, N.; de Kok, L. J.

    2000-01-01

    Notes are given on a project to create a database of bibliographic information, abstracts and keywords for publications on the biological effects of gaseous and heavy metal air pollution on plants and lichens.

  15. Predicting partitioning of volatile organic compounds from air into plant cuticular matrix by quantum chemical descriptors

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Based on theoretical linear solvation energy relationship and quantum chemical descriptors computed by AM1 Hamiltonian, a new model is developed to predict the partitioning of some volatile organic compounds between the plant cuticular matrix and air.

  16. Final Rule to Reduce Toxic Air Emissions from Lime Manufacturing Plants Fact Sheet

    Science.gov (United States)

    This page contains an August 2003 fact sheet with information regarding the National Emissions Standards for Hazardous Air Pollutants (NESHAP) for Lime Manufacturing Plants. This document provides a summary of the information for this NESHAP.

  17. 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.

  18. Reducing indoor air pollution by air conditioning is associated with improvements in cardiovascular health among the general population.

    Science.gov (United States)

    Lin, Lian-Yu; Chuang, Hsiao-Chi; Liu, I-Jung; Chen, Hua-Wei; Chuang, Kai-Jen

    2013-10-01

    Indoor air pollution is associated with cardiovascular effects, however, little is known about the effects of improving indoor air quality on cardiovascular health. The aim of this study was to explore whether improving indoor air quality through air conditioning can improve cardiovascular health in human subjects. We recruited a panel of 300 healthy subjects from Taipei, aged 20 and over, to participate in six home visits each, to measure a variety of cardiovascular endpoints, including high sensitivity-C-reactive protein (hs-CRP), 8-hydroxy-2'-deoxyguanosine (8-OHdG), fibrinogen in plasma and heart rate variability (HRV). Indoor particles and total volatile organic compounds (VOCs) were measured simultaneously at the participant's home during each visit. Three exposure conditions were investigated in this study: participants were requested to keep their windows open during the first two visits, close their windows during the next two visits, and close the windows and turn on their air conditioners during the last two visits. We used linear mixed-effects models to associate the cardiovascular endpoints with individual indoor air pollutants. The results showed that increases in hs-CRP, 8-OHdG and fibrinogen, and decreases in HRV indices were associated with increased levels of indoor particles and total VOCs in single-pollutant and two-pollutant models. The effects of indoor particles and total VOCs on cardiovascular endpoints were greatest during visits with the windows open. During visits with the air conditioners turned on, no significant changes in cardiovascular endpoints were observed. In conclusion, indoor air pollution is associated with inflammation, oxidative stress, blood coagulation and autonomic dysfunction. Reductions in indoor air pollution and subsequent improvements in cardiovascular health can be achieved by closing windows and turning on air conditioners at home. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Cooling Performance Characteristics on Mobile Air-Conditioning System for Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Ho-Seong Lee

    2013-01-01

    Full Text Available This study investigates the cooling performance characteristics of the mobile air-conditioning system using R744 (CO2 for the hybrid electric vehicle as an alternative to both the R-134a and the conventional air-conditioning system. The developed air-conditioning system is operated with an electric driven compressor in the battery driving mode and a belt driven compressor in the engine driving mode. The cooling performance characteristics of the developed system have been analyzed by experiments under various operating conditions of inlet air temperature, air flow rates for the gas cooler side and evaporator side, and electric compressor revolution respectively. As a result, cooling performances of the tested air-conditioning system for the EDC driving mode (electricity driven compressor were better than those for the BDC driving mode (belt driven compressor. The cooling capacity and cooling COP of the tested air-conditioning system for both driving modes were over 5.0 kW and 2.0, respectively. The observed cooling performance of the tested air-conditioning system may be sufficient for the cabin cooling of hybrid electric vehicles.

  20. Solar-air power plant. Interim report, January 1, 1980-November 1, 1981

    Energy Technology Data Exchange (ETDEWEB)

    Chen, I.

    1982-01-01

    The chimney conversion efficiency of transferring solar energy into wind energy for the proposed solar-air power plant has been investigated. The application of a chimney as the air-cooling system for a large-scale photovoltaic concentration power plant to transfer solar energy into electricity has also been studied. Several conclusions in reference to this basic research project and suggestions for further research phases are also summarized in this report.

  1. Evaluation of turbine systems for compressed air energy storage plants. Final report for FY 1976

    Energy Technology Data Exchange (ETDEWEB)

    Kartsounes, G.T.

    1976-10-01

    Compressed air energy storage plants for electric utility peak-shaving applications comprise four subsystems: a turbine system, compressor system, an underground air storage reservoir, and a motor/generator. Proposed plant designs use turbines that are derived from available gas and steam turbines with proven reliability. The study examines proposed turbine systems and presents an evaluation of possible systems that may reduce capital cost and/or improve performance. Six new turbine systems are identified for further economic evaluation.

  2. [Assessment of the air quality improment of cleaning and disinfection on central air-conditioning ventilation system].

    Science.gov (United States)

    Liu, Hongliang; Zhang, Lei; Feng, Lihong; Wang, Fei; Xue, Zhiming

    2009-09-01

    To assess the effect of air quality of cleaning and disinfection on central air-conditioning ventilation systems. 102 air-conditioning ventilation systems in 46 public facilities were sampled and investigated based on Hygienic assessment criterion of cleaning and disinfection of public central air-conditioning systems. Median dust volume decreased from 41.8 g/m2 to 0.4 g/m2, and the percentage of pipes meeting the national standard for dust decreased from 17.3% (13/60) to 100% (62/62). In the dust, median aerobic bacterial count decreased from 14 cfu/cm2 to 1 cfu/cm2. Median aerobic fungus count decreased from 10 cfu/cm2 to 0 cfu/cm2. The percentage of pipes with bacterial and fungus counts meeting the national standard increased from 92.4% (171/185) and 82.2% (152/185) to 99.4% (165/166) and 100% (166/166), respectively. In the ventilation air, median aerobic bacterial count decreased from 756 cfu/m3 to 229 cfu/m3. Median aerobic fungus count decreased from 382 cfu/m3 to 120 cfu/m3. The percentage of pipes meeting the national standard for ventilation air increased from 33.3% (81/243) and 62.1% (151/243) to 79.8% (292/366) and 87.7% (242/276), respectively. But PM10 rose from 0.060 mg/m3 to 0.068 mg/m3, and the percentage of pipes meeting the national standard for PM10 increased from 74.2% (13/60) to 90.2% (46/51). The cleaning and disinfection of central air-conditioning ventilation systems could have a beneficial effect of air quality.

  3. 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

  4. Influence of Cooling to Heating Load Ratio on Optimal Supply Water and Air Temperatures in an Air Conditioning System

    Science.gov (United States)

    Karino, Naoki; Shiba, Takashi; Yokoyama, Ryohei; Ito, Koichi

    In planning an air conditioning system, supply water and air temperatures are important factors from the viewpoint of energy saving and cost reduction. For example, lower temperature supply water and air for space cooling reduce the coefficient of performance of a refrigeration machine, and increase the thickness of heat insulation material. However, they enable larger temperature differences, and reduce equipment sizes and power demand. It is also an important subject to evaluate the effect of the supply water and air temperatures on energy saving and cost reduction on the annual basis by considering not only cooling but also heating loads. The purposes of this paper are to propose an optimal planning method for an air conditioning system with large temperature difference, and to analyze the effect of supply water and air temperatures on the long-term economics through a numerical study for an office building. As a result, it is shown that the proposed method effectively determines supply water and air temperatures, and the influence of the cooling to heating load ratio on the long-term economics is clarified.

  5. 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.

  6. Air entrainment by a plunging jet under intermittent vortex conditions

    OpenAIRE

    Kim, Kevin Jin; Corfman, Kyle; Li, Kevin; Kiger, Ken T.

    2011-01-01

    This fluid dynamic video entry to the 2011 APS-DFD Gallery of Fluid Motion details the transient evolution of the free surface surrounding the impact region of a low-viscosity laminar liquid jet as it enters a quiescent pool. The close-up images depict the destabilization and breakup of the annular air gap and the subsequent entrainment of bubbles into the bulk liquid.

  7. Combustion of Gaseous Fuels with High Temperature Air in Normal- and Micro-gravity Conditions

    Science.gov (United States)

    Wang, Y.; Gupta, A. K.

    2001-01-01

    The objective of this study is determine the effect of air preheat temperature on flame characteristics in normal and microgravity conditions. We have obtained qualitative (global flame features) and some quantitative information on the features of flames using high temperature combustion air under normal gravity conditions with propane and methane as the fuels. This data will be compared with the data under microgravity conditions. The specific focus under normal gravity conditions has been on determining the global flame features as well as the spatial distribution of OH, CH, and C2 from flames using high temperature combustion air at different equivalence ratio.

  8. Geologic mapping of the air intake shaft at the Waste Isolation Pilot Plant

    Energy Technology Data Exchange (ETDEWEB)

    Holt, R.M.; Powers, D.W. (IT Corporation (USA))

    1990-12-01

    The air intake shaft (AS) was geologically mapped from the surface to the Waste Isolation Pilot Plant (WIPP) facility horizon. The entire shaft section including the Mescalero Caliche, Gatuna Formation, Santa Rosa Formation, Dewey Lake Redbeds, Rustler Formation, and Salado Formation was geologically described. The air intake shaft (AS) at the Waste Isolation Pilot Plant (WIPP) site was constructed to provide a pathway for fresh air into the underground repository and maintain the desired pressure balances for proper underground ventilation. It was up-reamed to minimize construction-related damage to the wall rock. The upper portion of the shaft was lined with slip-formed concrete, while the lower part of the shaft, from approximately 903 ft below top of concrete at the surface, was unlined. As part of WIPP site characterization activities, the AS was geologically mapped. The shaft construction method, up-reaming, created a nearly ideal surface for geologic description. Small-scale textures usually best seen on slabbed core were easily distinguished on the shaft wall, while larger scale textures not generally revealed in core were well displayed. During the mapping, newly recognized textures were interpreted in order to refine depositional and post-depositional models of the units mapped. The objectives of the geologic mapping were to: (1) provide confirmation and documentation of strata overlying the WIPP facility horizon; (2) provide detailed information of the geologic conditions in strata critical to repository sealing and operations; (3) provide technical basis for field adjustments and modification of key and aquifer seal design, based upon the observed geology; (4) provide geological data for the selection of instrument borehole locations; (5) and characterize the geology at geomechanical instrument locations to assist in data interpretation. 40 refs., 27 figs., 1 tab.

  9. Implementing a Compressed Air System Leak Management Program at an Automotive Plant (Visteon's Monroe Plant)

    Energy Technology Data Exchange (ETDEWEB)

    None

    2001-01-01

    The energy team at Visteon’s Monroe plant, formerly owned by Ford Motor Company, implemented an ongoing compressed air system leak management program. The team developed an approach that combined a traditional “find and fix” effort with an innovative implementation and marketing program. As a result of the leak management program, compressed air system consumption was reduced by more than 50% on a per production unit basis.

  10. The Design of Research Laboratories. Part I: A General Assessment. Part II: Air Conditioning and Conditioned Rooms.

    Science.gov (United States)

    Legget, R. F.; Hutcheon, N. B.

    Design factors in the planning of research laboratories are described which include--(1) location, (2) future expansion, (3) internal flexibility, (4) provision of services, (5) laboratory furnishing, (6) internal traffic, (7) space requirements, and (8) building costs. A second part discusses air-conditioning and conditioned rooms--(1)…

  11. Can ornamental potted plants remove volatile organic compounds from indoor air? - a review

    DEFF Research Database (Denmark)

    Dela Cruz, Majbrit; Christensen, Jan H.; Thomsen, Jane Dyrhauge;

    2014-01-01

    Volatile organic compounds (VOCs) are found in indoor air, and many of these can affect human health (e.g. formaldehyde and benzene are carcinogenic). Plants affect the levels of VOCs in indoor environments, thus they represent a potential green solution for improving indoor air quality...

  12. A refractory steerable nozzle for air and fuel injection in thermal plant boiler combustors

    Energy Technology Data Exchange (ETDEWEB)

    Peschard, J.

    1993-10-01

    The horizontal walls of the tiltable (downwards or upwards) nozzles are corrugated in such a way that they may undergo thermal expansion without cracking. The vertical walls are double-face designed with air flowing inside for cooling. The nozzle is made of refractory steel. Application to air injection with or without pulverized coal or gas, in thermal plants.

  13. APEX (Air Pollution Exercise) Volume 9: Industrialist's Manual No. 5, Caesar's Rendering Plant.

    Science.gov (United States)

    Environmental Protection Agency, Research Triangle Park, NC. Office of Manpower Development.

    The Industrialist's Manual No. 5, Caesar's Rendering Plant is part of a set of 21 manuals (AA 001 009-001 029) used in APEX (Air Pollution Exercise), a computerized college and professional level "real world" game simulation of a community with urban and rural problems, industrial activities, and air pollution difficulties. The first two sections,…

  14. APEX (Air Pollution Exercise) Volume 7: Industrialist's Manual No. 2, People's Pulp Plant.

    Science.gov (United States)

    Environmental Protection Agency, Research Triangle Park, NC. Office of Manpower Development.

    The Industrialist's Manual No. 2, People's Pulp Plant is part of a set of 21 manuals (AA 001 009-001 029) used in APEX (Air Pollution Exercise), a computerized college and professional level "real world" game simulation of a community with urban and rural problems, industrial activities, and air pollution difficulties. The first two sections,…

  15. A comparative study for air pollution tolerance index of some terrestrial plant species

    OpenAIRE

    R.N. Lohe; B. Tyagi; Singh, V; P Tyagi; D.R. Khanna; R. Bhutiani

    2015-01-01

    Although water and land pollution are very dangerous, air pollution has its own peculiarities due to its transboundary dispersion of pollutants over the entire world. In any well planned urban set up, industrial pollution takes a back seat and vehicular emissions take precedence as the major cause of urban air pollution. In the present study, Air pollution tolerance index was calculated for various plant species growing at two sites Nagal village at Sahastradhara Road and the Clock Tower (the...

  16. Monitoring and analysis of air emissions based on condition models derived from process history

    Directory of Open Access Journals (Sweden)

    M. Liukkonen

    2016-12-01

    Full Text Available Evaluation of online information on operating conditions is necessary when reducing air emissions in energy plants. In this respect, automated monitoring and control are of primary concern, particularly in biomass combustion. As monitoring of emissions in power plants is ever more challenging because of low-grade fuels and fuel mixtures, new monitoring applications are needed to extract essential information from the large amount of measurement data. The management of emissions in energy boilers lacks economically efficient, fast, and competent computational systems that could support decision-making regarding the improvement of emission efficiency. In this paper, a novel emission monitoring platform based on the self-organizing map method is presented. The system is capable, not only of visualizing the prevailing status of the process and detecting problem situations (i.e. increased emission release rates, but also of analyzing these situations automatically and presenting factors potentially affecting them. The system is demonstrated using measurement data from an industrial circulating fluidized bed boiler fired by forest residue as the primary fuel and coal as the supporting fuel.

  17. Monitoring of Plant Light/Dark Cycles Using Air-coupled Ultrasonic Spectroscopy

    Science.gov (United States)

    Fariñas, M. D.; Sancho-Knapik, D.; Peguero-Pina, J.; Gil-Pelegrín, E.; Álvarez-Arenas, T. E. G.

    This work presents the application of a technique based on the excitation, sensing and spectral analysis of leaves thickness resonances using air-coupled and wide-band ultrasound to monitor variations in leaves properties due to the plant response along light/dark cycles. The main features of these resonances are determined by the tautness of the cells walls in such a way that small modifications produced by variations in the transpiration rate, stomata aperture or water potential have a direct effect on the thickness resonances that can be measured in a completely non-invasive and contactless way. Results show that it is possible to monitor leaves changes due to variations in light intensity along the diurnal cycle, moreover, the technique reveals differences in the leaf response for different species and also within the same species but for specimens grown under different conditions that present different cell structures at the tissue level.

  18. Automorphogenesis and gravitropism of plant seedlings grown under microgravity conditions.

    Science.gov (United States)

    Hoson, T; Saiki, M; Kamisaka, S; Yamashita, M

    2001-01-01

    Plant seedlings exhibit automorphogenesis on clinostats. The occurrence of automorphogenesis was confirmed under microgravity in Space Shuttle STS-95 flight. Rice coleoptiles showed an inclination toward the caryopsis in the basal region and a spontaneous curvature in the same adaxial direction in the elongating region both on a three-dimensional (3-D) clinostat and in space. Both rice roots and Arabidopsis hypocotyls also showed a similar morphology in space and on the 3-D clinostat. In rice coleoptiles, the mechanisms inducing such an automorphic curvature were studied. The faster-expanding convex side of rice coleoptiles showed a higher extensibility of the cell wall than the opposite side. Also, in the convex side, the cell wall thickness was smaller, the turnover of the matrix polysaccharides was more active, and the microtubules oriented more transversely than the concave side, and these differences appear to be causes of the curvature. When rice coleoptiles grown on the 3-D clinostat were placed horizontally, the gravitropic curvature was delayed as compared with control coleoptiles. In clinostatted coleoptiles, the corresponding suppression of the amyloplast development was also observed. Similar results were obtained in Arabidopsis hypocotyls. Thus, the induction of automorphogenesis and a concomitant decrease in graviresponsiveness occurred in plant shoots grown under microgravity conditions.

  19. Influence of Cycle Air Parameters and Flue Gas Path Aerodynamics on Efficiency of Gas Turbine and Steam Gas Plants

    Directory of Open Access Journals (Sweden)

    A. S. Grinchouk

    2009-01-01

    Full Text Available The paper considers an influence of gas-air path aerodynamic resistance for a gas-turbine plant, barometric pressure, air moisture and outside air temperature on parameters, efficiency and characteristics of electric power plants with gas-turbine and combined-cycle sets. Calculations and analysis have been executed for Alstom GT13E2 gas-turbine which is included in composition of Steam Gas Plant-230 at the Minsk Thermal Power Plant No.3.

  20. PHYTOREMEDIATION OF GROUNDWATER AT AIR FORCE PLANT 4, CARSWELL, TEXAS - INNOVATIVE TECHNOLOGY EVALUATION REPORT

    Science.gov (United States)

    Over 600 Cottonwood trees were planted over a shallow groundwater plume in an attempt to detoxify the trichloroethylene (TCE) in a groundwater plume at a former Air Force facility. Two planting techniques were used: rooted stock about two years old, and 18 inch cuttings were inst...

  1. PHYTOREMEDIATION OF GROUNDWATER AT AIR FORCE PLANT 4, CARSWELL, TEXAS - INNOVATIVE TECHNOLOGY EVALUATION REPORT

    Science.gov (United States)

    Over 600 Cottonwood trees were planted over a shallow groundwater plume in an attempt to detoxify the trichloroethylene (TCE) in a groundwater plume at a former Air Force facility. Two planting techniques were used: rooted stock about two years old, and 18 inch cuttings were inst...

  2. Parametric Analysis of a Rotary Type Liquid Desiccant Air Conditioning System

    Directory of Open Access Journals (Sweden)

    M. Mujahid Rafique

    2016-04-01

    Full Text Available Now days, air conditioning systems are a must for almost every commercial and residential building to achieve comfortable indoor conditions. The increasing energy demand, and increasing oil prices and pollution levels raise the need for alternative air conditioning systems which can efficiently utilize renewable energy resources. The liquid desiccant-based air conditioning method is pollution free and thermal energy-based cooling techniques can use low grade thermal energy resources like solar energy, waste heat, etc. These systems have an additional advantage of cleaning bacteria and fungi from the air. In this paper, a newly proposed rotary liquid desiccant air conditioning system has been investigated theoretically. Most direct contact liquid desiccant cooling systems have the problem of desiccant carryover which can be eliminated using the proposed system. The effects of various key parameters and climatic conditions on the performance of the system have been evaluated. The results showed that if the key parameters of the system are controlled effectively, the proposed cooling system has the ability to achieve the desired supply air conditions. The system can achieve high coefficient of performance (COP under different conditions. The dehumidifier has a sensible heat ratio (SHR in the range of 0.3–0.6 for different design, climatic, and operating conditions. The system can remove latent load efficiently in applications which require good humidity control.

  3. Impaired Air Conditioning within the Nasal Cavity in Flat-Faced Homo.

    Science.gov (United States)

    Nishimura, Takeshi; Mori, Futoshi; Hanida, Sho; Kumahata, Kiyoshi; Ishikawa, Shigeru; Samarat, Kaouthar; Miyabe-Nishiwaki, Takako; Hayashi, Misato; Tomonaga, Masaki; Suzuki, Juri; Matsuzawa, Tetsuro; Matsuzawa, Teruo

    2016-03-01

    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 severe climates of

  4. 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

  5. Computerized Simulation of Automotive Air-Conditioning System: A Parametric Study

    Directory of Open Access Journals (Sweden)

    Haslinda Mohamed Kamar

    2013-01-01

    Full Text Available This paper presents results of a parametric study performed on an automotive air-conditioning (AAC system of a passenger car. The goals are to assess the effects of varying the volumetric flow rate of supply air, number of occupants, vehicle speed, and the fractional ventilation air intake (XOA, on the dry-bulb temperature and specific humidity of the air inside the passengers cabin, and on the evaporator coil cooling load of the AAC system. Results of the parametric study show that increasing the supply air flow rate reduces the dry-bulb temperature of the cabin air, increases both the specific humidity of the air and the evaporator coil load. Increasing the number of occupants in the passenger cabin causes the cabin air temperature, specific humidity and the evaporator coil load to increase. Increasing the vehicle speed causes the specific humidity of the cabin air and the evaporator coil cooling load to increase but the dry-bulb temperature of the air is not significantly affected. Increasing the fractional fresh air intake (XOA also increases the cabin air specific humidity and the evaporator coil cooling load.

  6. System and method for conditioning intake air to an internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Sellnau, Mark C.

    2015-08-04

    A system for conditioning the intake air to an internal combustion engine includes a means to boost the pressure of the intake air to the engine and a liquid cooled charge air cooler disposed between the output of the boost means and the charge air intake of the engine. Valves in the coolant system can be actuated so as to define a first configuration in which engine cooling is performed by coolant circulating in a first coolant loop at one temperature, and charge air cooling is performed by coolant flowing in a second coolant loop at a lower temperature. The valves can be actuated so as to define a second configuration in which coolant that has flowed through the engine can be routed through the charge air cooler. The temperature of intake air to the engine can be controlled over a wide range of engine operation.

  7. The use of air-conditioning to improve performances of personnel; Airco inzet voor betere prestaties

    Energy Technology Data Exchange (ETDEWEB)

    Havenaar, D.

    2012-04-01

    The combination of temperature, air humidity, ventilation and air movement highly determines the comfort feeling of personnel. Moreover, these factors enable optimal performance. Air-conditioning, but particularly temperature control are important instruments in realizing such an optimal performance climate. [Dutch] De combinatie van temperatuur, luchtvochtigheid, luchtverversing en luchtbeweging bepaalt in hoge mate het behaaglijkheidsgevoel van personeel. Daarnaast zorgen deze factoren ervoor dat optimaal gepresteerd kan worden. Om dit optimale prestatieklimaat te realiseren is airconditioning maar vooral temperatuurbeheersing een belangrijk hulpmiddel.

  8. Air Conditioning Stall Phenomenon Testing, Model Development, and Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Irminger, Philip [ORNL; Rizy, D Tom [ORNL; Li, Huijuan [ORNL; Smith, Travis [ORNL; Rice, C Keith [ORNL; Li, Fangxing [ORNL; Adhikari, Sarina [ORNL

    2012-01-01

    Electric distribution systems are experiencing power quality issues of extended reduced voltage due to fault-induced delayed voltage recovery (FIDVR). FIDVR occurs in part because modern air conditioner (A/C) and heat pump compressor motors are much more susceptible to stalling during a voltage sag or dip such as a sub-transmission fault. They are more susceptible than older A/C compressor motors due to the low inertia of these newer and more energy efficient motors. There is a concern that these local reduced voltage events on the distribution system will become more frequent and prevalent and will combine over larger areas and challenge transmission system voltage and ultimately power grid reliability. The Distributed Energy Communications and Controls (DECC) Laboratory at Oak Ridge National Laboratory (ORNL) has been employed to (1) test, (2) characterize and (3) model the A/C stall phenomenon.

  9. Microwave Disinfection in a Ventilation and Air-Conditioning System

    Institute of Scientific and Technical Information of China (English)

    LU Zhen; ZHANG Ji-li; MA Liang-dong; HE Juan

    2009-01-01

    Because of its broad spectrum and high efficiency,the microwave disinfection was used to control the airborne microbial contaminates in VAC system.Some microwave disinfection devices were developed com-bined with air filter,the design and calculation method was presented,and the disinfection effects on White staphylococcus,Staphylococcus aureus,Bacillus Subtilis,Escherichi coli were measured.The results show that the major influence factors on disinfection effect are microwave power,water-content of filter material,dis-infecting duration.After 15 min,the kill ratio is>90%,and the log value is>1.The microwave field is uni-form and the kill effect of bacteria on each surface of filter is the same,without statistically significant differ-ence.

  10. Dimensional approach on hot air turbine power plant in opened cycle for straw recycling

    Science.gov (United States)

    Bălănescu, D. T.; Homutescu, V. M.; Atanasiu, M. V.

    2016-08-01

    Currently, disposal of straw is one of the biggest problems that crop plant producers are facing. The ideal case implies not only to get rid of straw but also to recover its energetic potential. In this context, the performance of a hot air turbine power plant operating in open cycle, with straw as fuel, was analyzed in a previous study and proved to be a very interesting solution for straw disposal. As consequence, dimensional analysis of the hot air turbine power plant is required into the next step and this makes the subject of the present study. The dimensional analysis is focused on the compressed air heater - the largest component of the Power Plant, with crucial role in what concerns its entire size and mass. Once both performance and dimensional analysis performed, the final conclusions are drawn in an overall approach, by taking also into consideration the economic aspects.

  11. Desiccant Enhanced Evaporative Air-Conditioning (DEVap): Evaluation of a New Concept in Ultra Efficient Air Conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Kozubal, E.; Woods, J.; Burch, J.; Boranian, A.; Merrigan, T.

    2011-01-01

    NREL has developed the novel concept of a desiccant enhanced evaporative air conditioner (DEVap) with the objective of combining the benefits of liquid desiccant and evaporative cooling technologies into an innovative 'cooling core.' Liquid desiccant technologies have extraordinary dehumidification potential, but require an efficient cooling sink. DEVap's thermodynamic potential overcomes many shortcomings of standard refrigeration-based direct expansion cooling. DEVap decouples cooling and dehumidification performance, which results in independent temperature and humidity control. The energy input is largely switched away from electricity to low-grade thermal energy that can be sourced from fuels such as natural gas, waste heat, solar, or biofuels.

  12. Air pollution tolerance index of plants around brick kilns in Rawalpindi, Pakistan.

    Science.gov (United States)

    Achakzai, Khanoranga; Khalid, Sofia; Adrees, Muhammad; Bibi, Aasma; Ali, Shafaqat; Nawaz, Rab; Rizwan, Muhammad

    2017-04-01

    In any contaminated environment, the sensitive plant species can serve as bio-indicator of air pollution while tolerant plant species can act as a sink for air pollutants. Air pollution tolerance index (APTI) is an important tool to screen out plants based on their tolerance or sensitivity level to different air pollutants. The present study was aimed to identify the sensitive and tolerant plant species in the vicinity of brick kilns in the Rawalpindi city. To determine the susceptibility level of the selected plant species, four biochemical parameters, ascorbic acid, total chlorophyll content, relative water content and pH of leaf extract, were assessed and APTI was calculated. Plant sampling was carried out with increasing distance of 100, 300 and 500 m around three brick kiln sites and APTI values were calculated by following the standard methods. The results of the study revealed that among nine studied plant species, Calotropis procera (APTI = 20.05) and Althernanthera pungens (APTI = 17.13) were found to be the most tolerant species, whereas Malva neglecta (APTI = 8.83) was found to be the most sensitive species. Inconsistent trend of variations was seen in the APTI values at each site. The present study suggested that the most tolerant species, C. procera and A. pungens, could be grown in the vicinity of such pollution sources as a remedial measure of brick kiln pollution.

  13. Phytoremediation of Groundwater at Air Force Plant 4, Carswell, Texas

    Science.gov (United States)

    2003-09-01

    swings in soil water potential through transpiration and by the continual addition of water-retentive organic matter. In essence , the 6 plant-microbe...ability of trees to act as pumps was noted in the late 19th century when Eucalyptus trees were planted in Italy and Algeria to dry up marshes. The...development of short rotation crops such as cottonwoods, hybrid poplar, willow, eucalyptus , or other energy crops, requires consideration of operational

  14. 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.

  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. Temperature and Humidity Independent Control Research on Ground Source Heat Pump Air Conditioning System

    Science.gov (United States)

    Chen, G.; Wang, L. L.

    Taking green demonstration center building air conditioning system as an example, this paper presents the temperature and humidity independent control system combined with ground source heat pump system, emphasis on the design of dry terminal device system, fresh air system and ground source heat pump system.

  17. All air treatments are realisable energy efficiently. Room air conditioning based on membranes; Alle Luftbehandlungen energiesparend realisierbar. Membranbasierte Raumklimatisierung

    Energy Technology Data Exchange (ETDEWEB)

    Rosenbaum, Hannes [ILK Dresden gGmbH, Dresden (Germany). Hauptbereich Luft- und Klimatechnik

    2011-12-15

    Membrane elements for indirect liquid sorption processes enable a decentralized air conditioning. A suitable design of the heat transmitting and substance transmitting components needs to be developed yet. Then, membrane heat exchangers perform a hygienic, condensate-free dehumidification energy efficiently.

  18. Method for acquiring part load distribution coefficient of air conditioning system

    Institute of Scientific and Technical Information of China (English)

    丁勇; 李百战; 谭颖

    2009-01-01

    This paper presents a method to acquire runtime distribution ratio of building air conditioning system under part load condition (part load coefficient of system) through practical energy consumption data. By utilizing monthly energy consumption data of the entire year as the analysis object,this paper identifies data distribution,verifies distribution characteristics and analyzes distribution probability density for the issue of running time distribution ratio of air conditioning system in part load zones in the whole operation period,thus providing a basic calculation basis for an overall analysis of energy efficiency of air conditioning system. In view of the general survey of public building energy consumption carried by the government of Chongqing,this paper takes the governmental office building as an example,the part load ratio coefficient corresponding to practical running of air conditioning system of governmental office building in Chongqing is obtained by utilizing the above probability analysis and the solving method of probability density function. By utilizing the ratio coefficient obtained using this method,the part load coefficient with any running ratio of air conditioning system can be obtained according to the requirement of analysis,which can be used in any load ratio for analyzing running energy efficiency of air conditioning system.

  19. Influence of cooling face masks on nasal air conditioning and nasal geometry.

    Science.gov (United States)

    Lindemann, J; Hoffmann, T; Koehl, A; Walz, E M; Sommer, F

    2017-06-01

    Nasal geometries and temperature of the nasal mucosa are the primary factors affecting nasal air conditioning. Data on intranasal air conditioning after provoking the trigeminal nerve with a cold stimulus simulating the effects of an arctic condition is still missing. The objective was to investigate the influence of skin cooling face masks on nasal air conditioning, mucosal temperature and nasal geometry. Standardized in vivo measurements of intranasal air temperature, humidity and mucosal temperature were performed in 55 healthy subjects at defined detection sites before and after wearing a cooling face mask. Measurements of skin temperature, rhinomanometry and acoustic rhinometry were accomplished. After wearing the face mask the facial skin temperature was significantly reduced. Intranasal air temperature did not change. Absolute humidity and mucosal temperature increased significantly. The acoustic rhinometric results showed a significant increase of the volumes and the cross-sectional areas. There was no change in nasal airflow. Nasal mucosal temperature, humidity of inhaled air, and volume of the anterior nose increased after application of a cold face mask. The response is mediated by the trigeminal nerve. Increased mucosal temperatures as well as changes in nasal geometries seem to guarantee sufficient steady intranasal nasal air conditioning.

  20. Measures against the adverse impact of natural wind on air-cooled condensers in power plant

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The natural wind plays disadvantageous roles in the operation of air-cooled steam condensers in power plant.It is of use to take various measures against the adverse effect of wind for the performance improvement of air-cooled condensers.Based on representative 2×600 MW direct air-cooled power plant,three ways that can arrange and optimize the flow field of cooling air thus enhance the heat transfer of air-cooled condensers were proposed.The physical and mathematical models of air-cooled condensers with various flow leading measures were presented and the flow and temperature fields of cooling air were obtained by CFD simulation.The back pressures of turbine were calculated for different measures on the basis of the heat transfer model of air-cooled condensers.The results show that the performance of air-cooled condensers is improved thus the back pressure of turbine is lowered to some extent by taking measures against the adverse impact of natural wind.

  1. Greenhouse Gas Reporting Requirements Related to Stationary Refrigeration and Air Conditioning

    Science.gov (United States)

    Provides links to information about parts of the 2009 Mandatory Reporting of Greenhouse Gases Rule that are relevant to owners and importers of stationary refrigeration and air-conditioning equipment.

  2. 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.

  3. Transitioning to Low-GWP Alternatives in Residential and Commercial Air Conditioning

    Science.gov (United States)

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

  4. Transitioning to Low-GWP Alternatives in Residential and Light Commercial Air Conditioning

    Science.gov (United States)

    This fact sheet provides current information on low global warming potential (GWP) alternatives for new equipment in residential and light commercial air conditioning (AC), in lieu of high-GWP hydrofluorocarbons (HFCs).

  5. Fuel Savings and Emission Reductions from Next-Generation Mobile Air Conditioning Technology in India: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Chaney, L.; Thundiyil, K.; Chidambaram, S.; Abbi, Y. P.; Anderson, S.

    2007-05-01

    This paper quantifies the mobile air-conditioning fuel consumption of the typical Indian vehicle, exploring potential fuel savings and emissions reductions these systems for the next generation of vehicles.

  6. Influences of the Indoor Environment on Heat, Air, and Moisture Conditions in the Component

    DEFF Research Database (Denmark)

    Steskens, Paul Wilhelmus Maria Hermanus; Rode, Carsten; Janssen, Hans

    2008-01-01

    Current models to predict heat, air and moisture (HAM) conditions in building components assume uniform boundary conditions, both for the temperature and relative humidity of the air in an indoor space as well as for the heat and moisture surface transfer coefficients. The heat and moisture surface...... transfer coefficients strongly depend on the local air velocity, local temperature, water-material interactions, water content at the material surface, and the surface texture of the material. Moreover, due to local heat and moisture sources, imperfect mixing and microclimatic effects, temperature...... and relative humidity in the adjacent air are seldom uniform. In order to obtain a reliable prediction of the HAM conditions in a building component, an accurate description of the indoor (and outdoor) boundary conditions is required. The objective of the present paper is to analyze the influence...

  7. Evaluating Membrane Processes for Air Conditioning; Highlights in Research and Development, NREL (National Renewable Energy Laboratory)

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-06-01

    This NREL Highlight discusses a recent state-of-the-art review of membrane processes for air conditioning that identifies future research opportunities. This highlight is being developed for the June 2015 S&T Alliance Board meeting.

  8. Air conditioning management of huge rooms; Gestion climatique des locaux de grande dimension

    Energy Technology Data Exchange (ETDEWEB)

    Guitton, P. [Electricite de France (EDF), 78 - Chatou (France); Izard, J.L. [Ecole d`Architecture de Marseille-Luminy, 13 - Marseille-Luminy (France); Wurtz, E. [La Rochelle Universite, 17 - La Rochelle, LEPTAB (France)] [and others

    1999-09-01

    This conference was organized by the section `air-conditioning engineering` of the French society of thermal engineers (SFT). This document comprises the abridged versions of the communications and deals with: air-conditioning using displacement: experience feedback on tertiary applications and development of a dimensioning tool, thermal response of linear atria, application of the zonal method to the description of the temperature field and flows pattern inside an auditorium, theoretical and experimental study of air renewal inside industrial rooms, management of huge rooms, design of new optimized buildings and use of the TAS software, can TRNSYS and Comis codes be used for huge spaces?, experimental study of the thermal-aeraulic conditions generated by a displacement air-conditioning device. (J.S.)

  9. Temperature and humidity independent control (THIC) of air-conditioning system

    CERN Document Server

    Liu, Xiaohua; Zhang, Tao

    2014-01-01

    This book presents the main components of the Temperature and Humidity Independent Control (THIC) of air-conditioning systems, including dehumidification devices, high-temperature cooling devices and indoor terminal devices.

  10. Hybrid Power Forecasting Model for Photovoltaic Plants Based on Neural Network with Air Quality Index

    Directory of Open Access Journals (Sweden)

    Idris Khan

    2017-01-01

    Full Text Available High concentration of greenhouse gases in the atmosphere has increased dependency on photovoltaic (PV power, but its random nature poses a challenge for system operators to precisely predict and forecast PV power. The conventional forecasting methods were accurate for clean weather. But when the PV plants worked under heavy haze, the radiation is negatively impacted and thus reducing PV power; therefore, to deal with haze weather, Air Quality Index (AQI is introduced as a parameter to predict PV power. AQI, which is an indication of how polluted the air is, has been known to have a strong correlation with power generated by the PV panels. In this paper, a hybrid method based on the model of conventional back propagation (BP neural network for clear weather and BP AQI model for haze weather is used to forecast PV power with conventional parameters like temperature, wind speed, humidity, solar radiation, and an extra parameter of AQI as input. The results show that the proposed method has less error under haze condition as compared to conventional model of neural network.

  11. [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.

  12. 54 FR 38044: National Emission Standards for Hazardous Air Pollutants; Benzene Emissions From Maleic Anhydride Plants, Ethylbenzene/Styrene Plants, Benzene Storage Vessels, Benzene Equipment Leaks, and Coke By- Product Recovery Plants

    Science.gov (United States)

    Final Rule on National Emission Standards for Hazardous Air Pollutants; Benzene Emissions From Maleic Anhydride Plants, Ethylbenzene/Styrene Plants, Benzene Storage Vessels, Benzene Equipment Leaks, and Coke By-Product Recovery Plants.

  13. New Energy-Efficient Electromagnetic Clutch for Automotive Air Conditioning Compressors

    OpenAIRE

    Baumgart, Rico; van der Seylberg, Frank; Aurich, Joerg; von Unwerth, Thomas

    2012-01-01

    Even if the air conditioning is switched off, the internal combustion engine in today’s cars continues to drive the common compressor. To avoid resulting power losses, the automotive industry aspires to apply electromagnetic clutches. When the air conditioning is used, however, CO2-emission increases significantly because the electromag-netic coil consumes electricity. The CO2-reduction per year is consequently very low, which is why new compressor clutches were developed that do not require ...

  14. Refrigeration, heating and air conditioning pocket book 2012; Kaelte, Waerme, Klima. Taschenbuch 2012

    Energy Technology Data Exchange (ETDEWEB)

    Schaedlich, Sylvia (ed.)

    2011-07-01

    The refrigeration, heating and air conditioning pocket book 2012 contains a calendar of important events and technical fairs. A publication of this type requires constant updating, and this is what was done in this pocket book. The technical documentation contains the following aspects: General working basis; special working basis of refrigeration; coolants; refrigeration; air-conditioning technology; heating technology; measurement and control technology; general information.

  15. Paddy plants inoculated with PGPR show better growth physiology and nutrient content under saline condition

    Directory of Open Access Journals (Sweden)

    Yachana Jha

    2013-09-01

    Full Text Available The possible role of plant growth-promoting rhizobacteria (PGPR to alleviate salt stress during plant growth has been studied on paddy rice (Oryza sativa L. 'GJ-17' under greenhouse conditions; the study included growth parameters, mineral concentration, and antioxidant enzyme level. Salinity reduced plant growth, but PGPR inoculation reduced its harmful effect up to 1% salinity. Plants inoculated with PGPR under saline conditions showed 16% higher germination, 8% higher survival, 27% higher dry weight, and 31% higher plant height. Similarly, PGPR inoculated plants showed increased concentrations of N(26%, P (16%, K (31%, and reduced concentrations of Na (71% and Ca (36% as compared to non-inoculated control plants under saline conditions. Plants inoculated with PGPR under saline conditions also showed significant variations in antioxidant levels and growth physiology. Results suggested that inoculation with PGPR Bacillus pumilus and Pseudomonas pseudoalcaligenes in salt-stressed plants could help to alleviate salt stress in the paddy.

  16. Use of Air2Air Technology to Recover Fresh-Water from the Normal Evaporative Cooling Loss at Coal-Based Thermoelectric Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Ken Mortensen

    2009-06-30

    This program was undertaken to build and operate the first Air2Air{trademark} Water Conservation Cooling Tower at a power plant, giving a validated basis and capability for water conservation by this method. Air2Air{trademark} water conservation technology recovers a portion of the traditional cooling tower evaporate. The Condensing Module provides an air-to-air heat exchanger above the wet fill media, extracting the heat from the hot saturated moist air leaving in the cooling tower and condensing water. The rate of evaporate water recovery is typically 10%-25% annually, depending on the cooling tower location (climate).

  17. Influences of the Indoor Environment on Heat, Air and Moisture Conditions in The Building Component: Boundary Conditions Modeling

    DEFF Research Database (Denmark)

    Steskens, Paul Wilhelmus Maria Hermanus; Rode, Carsten; Janssen, Hans

    2008-01-01

    used to investigate this influence. The research showed that the indoor environmental conditions and local airflow velocity have a relatively large influence on the predicted HAM conditions in a building component. The influence of the convective surface heat transfer coefficient on the HAM performance...... is not acceptable for the convective surface heat transfer coefficient. The study showed that the influence on the surface relative humidity is limited.......Current models to predict heat, air and moisture (HAM) conditions in building components assume uniform boundary conditions, both for the temperature and relative humidity of the air in an indoor space as well as for the surface transfer coefficients. Such models cannot accurately predict the HAM...

  18. The new exchangers in refrigeration and air, conditioning applications

    Energy Technology Data Exchange (ETDEWEB)

    Marvillet, Ch. [CEA, 38 - Grenoble (France). GRETh

    1997-12-31

    The investigation carried out by the `heat exchangers` network has revealed a number of points which should be noted here at the beginning of this presentation. It has been observed that most of today`s products (fin and tube heat exchangers) are designed along traditional lines. However despite this `conservatism`, a lot of attention is found on the technical and innovative techniques used in other areas of the world (particularly in Japan). Moreover, some of these innovative techniques (micro fin tubes, louvered fins) tend to be more frequently applied than others, and their gradual introduction into products which are `made in the EEC` is to be expected. The purpose of this paper is to respond, at least partially, to the interest shown by the industries contacted. during this investigation in these new techniques. In the first chapter, an overview of the information available today on high performance thermal heat exchange surfaces will be given. Micro-fin tubes and louvered fins will be the two surfaces considered in the first part of this document. According to this investigation, the fin and tube heat exchanger remains the only product available today for evaporating and condensing refrigerant applications using air as the fluid to be treated. Other technological solutions exist, however; brazed fin and plate heat exchangers commonly used in applications where compactness is an essential quality will be examined in the second part of this document. Moreover, the use of fluids which will replace CFCS in the years to come, and the possible comeback of ammonia will certainly have consequences on the design of evaporators and condensers. In the third part of this document the effects of these changes on fin and tube heat exchangers will be evaluated, and the first published results of the use of substitution fluids will be discussed. (author) 16 refs.

  19. A review of potential alternatives for air cleaning at the Hanford Waste Vitrification Plant

    Energy Technology Data Exchange (ETDEWEB)

    Sehmel, G.A.

    1990-07-01

    Pacific Northwest Laboratory conducted this review in support of the Hanford Waste Vitrification Plant (HWVP) being designed by Fluor Daniel Inc. for the US Department of Energy (DOE). The literature on air cleaning systems is reviewed to identify potential air cleaning alternatives that might be included in the design of HWVP. An overview of advantages/disadvantages of the various air cleaning technologies follows. Information and references are presented for the following potential air cleaning alternatives: deep-bed glass-fiber filters (DBGF), high-efficiency particulate air filters (HEPA), remote modular filter systems, high-efficiency mist eliminators (HEME), electrostatic precipitators, and the sand filter. Selected information is summarized for systems in the United States, Belgium, Japan, and West Germany. This review addresses high-capacity air cleaning systems currently used in the nuclear industry and emphasizes recent developments. 10 refs., 9 figs., 3 tabs.

  20. 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.

  1. 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.

  2. Air-side performance of a micro-channel heat exchanger in wet surface conditions

    Directory of Open Access Journals (Sweden)

    Srisomba Raviwat

    2017-01-01

    Full Text Available The effects of operating conditions on the air-side heat transfer, and pressure drop of a micro-channel heat exchanger under wet surface conditions were studied experimentally. The test section was an aluminum micro-channel heat exchanger, consisting of a multi-louvered fin and multi-port mini-channels. Experiments were conducted to study the effects of inlet relative humidity, air frontal velocity, air inlet temperature, and refrigerant temperature on air-side performance. The experimental data were analyzed using the mean enthalpy difference method. The test run was performed at relative air humidities ranging between 45% and 80%; air inlet temperature ranges of 27, 30, and 33°C; refrigerant-saturated temperatures ranging from 18 to 22°C; and Reynolds numbers between 128 and 166. The results show that the inlet relative humidity, air inlet temperature, and the refrigerant temperature had significant effects on heat transfer performance and air-side pressure drop. The heat transfer coefficient and pressure drop for the micro-channel heat exchanger under wet surface conditions are proposed in terms of the Colburn j factor and Fanning f factor.

  3. Influence of Ventilation Ratio on Desiccant Air Conditioning System's Efficiency Performance

    Science.gov (United States)

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

    Ventilation air is a concern for engineers since ventilated air controls indoor air contamination; additional ventilation, however, increases the energy consumption of buildings. The study investigates the energy efficiency performance of the desiccant dehumidification air conditioning system in the context of ventilation for a hot-humid climate such as summer in Japan. The investigation focuses on the variable ratio of ventilation air as required by the application of air conditioning system. The COP of the desiccant air conditioning system is determined. The evaluation is subsequently performed by comparing the desiccant based system with the conventional absorption cooling system and the vapor compression cooling system. Based on 12 desiccant rotor simulations, it is found that the desiccant regeneration temperature required varies between 47°C to 85°C as ventilation ratio increases from 0. 0 to 100%, and up to 52. 5°C as the ventilation ratio achieves 14%. The heat required for regenerating desiccant accounts for 55% and higher of the system's total heat consumption; the system is expected to be energy efficient by using wasted heat from the absorption chiller for desiccant regeneration; and its energy efficiency expands as the ratio of ventilation air rises above 15% compared with the conventional absorption cooling system. The energy efficiency also benefits as the ratio rises beyond 70% against the conventional vapor compression cooling system.

  4. Air emission from the co-combustion of alternative derived fuels within cement plants: Gaseous pollutants.

    Science.gov (United States)

    Richards, Glen; Agranovski, Igor E

    2015-02-01

    Cement manufacturing is a resource- and energy-intensive industry, utilizing 9% of global industrial energy use while releasing more than 5% of global carbon dioxide (CO₂) emissions. With an increasing demand of production set to double by 2050, so too will be its carbon footprint. However, Australian cement plants have great potential for energy savings and emission reductions through the substitution of combustion fuels with a proportion of alternative derived fuels (ADFs), namely, fuels derived from wastes. This paper presents the environmental emissions monitoring of 10 cement batching plants while under baseline and ADF operating conditions, and an assessment of parameters influencing combustion. The experiential runs included the varied substitution rates of seven waste streams and the monitoring of seven target pollutants. The co-combustion tests of waste oil, wood chips, wood chips and plastic, waste solvents, and shredded tires were shown to have the minimal influence when compared to baseline runs, or had significantly reduced the unit mass emission factor of pollutants. With an increasing ADF% substitution, monitoring identified there to be no subsequent emission effects and that key process parameters contributing to contaminant suppression include (1) precalciner and kiln fuel firing rate and residence time; (2) preheater and precalciner gas and material temperature; (3) rotary kiln flame temperature; (4) fuel-air ratio and percentage of excess oxygen; and (5) the rate of meal feed and rate of clinker produced.

  5. Refrigerant Control Strategies for Residential Air-Conditioning and Heat-Pump System

    Institute of Scientific and Technical Information of China (English)

    SU Shun-yu; ZHANG Chun-zhi; CHEN Jian

    2009-01-01

    This paper simulated the optimal refrigerant charge inventory of a refrigeration system in air-con-ditioning operation and heat-pump operation respectively,and studied the refrigerant control strategies in this system.The void fraction in two-phase fluid region was calculated by Harms model.And based on distributed parameter model and Harms model,the refrigerant charge inventory in condenser and evaporator were calculated and analyzed in air-conditioning conditions and heat-pump conditions,respectively.The calculating results of dif-ferent refrigerant mass between refrigeration and heating conditions indicate that the optimal refrigerant charge inventory in heat-pump conditions is lower than that in air-eonditioning conditions.To avoid the decrease of COP due to the surplus refrigerant in heating conditions,we introduced the liquid reservoir control method and associate capillary control method.Both of them could increase the heating capacity of the air-source heat pump-The difference of optimal refrigerant charge inventory in air-conditioning and heat-pump system can be controlled by the liquid reservoir or the associate capillary.

  6. Investigation on regeneration and energy storage characteristics of a solar liquid desiccant air-conditioning system

    Institute of Scientific and Technical Information of China (English)

    SHI Mingheng; DU Bin; ZHAO Yun

    2007-01-01

    Solar liquid desiccant air-conditioner is a new air-conditioning system in which liquid desiccant can be regenerated by solar energy and energy can be stored in the form of chemical energy in the liquid desiccant.In this paper regeneration and energy storage characteristics were studied theoretically and experimentally.Two criterion equations for heat and mass transfer in the regeneration process were obtained.The main factors that influence the regeneration process were analyzed.A principal solar liquid desiccant air-conditioning system under energy storage operating mode is proposed.

  7. Air cleaning efficiency of deodorant materials under dynamic conditions: effect of air flow rate

    DEFF Research Database (Denmark)

    Mizutani, Chiyomi; Bivolarova, Mariya Petrova; Melikov, Arsen Krikor

    2014-01-01

    was evaluated as deodorant materials neutralising ammonia in air. The deodorant material efficiency was tested in a special experimental set-up consisting of a straight pipe section, an ammonia gas generator, a fan and a textile frame. The deodorant materials, placed in the pipe, were exposed to a flow of air...... mixed with ammonia gas at a concentration of 20 ppm and velocities of 0.05, 0.15, 0.3 and 1.2 m/s. The activated carbon fibers treated with acid had a high deodorizing effect for ammonia (0.8) at a velocity of 0.05 m/s. The deodorizing effect of this material decreased with the increase in the velocity....... The porous activated carbon fiber fabric did not have a deodorant effect....

  8. Photocatalysis for continuous air purification in wastewater treatment plants: from lab to reality.

    Science.gov (United States)

    Portela, R; Tessinari, R F; Suárez, S; Rasmussen, S B; Hernández-Alonso, M D; Canela, M C; Avila, P; Sánchez, B

    2012-05-01

    The photocatalytic efficiency of TiO(2)-SiMgO(x) plates to oxidize H(2)S was first evaluated in a flat laboratory reactor with 50 mL min(-1) synthetic air containing 100 ppm H(2)S in the presence of humidity. The use of the photocatalyst-adsorbent hybrid material enhanced the photocatalytic activity in terms of pollutant conversion, selectivity, and catalyst lifetime compared to previous H(2)S tests with pure TiO(2) because total H(2)S elimination was maintained for more than 30 operating hours with SO(2) appearing in the outlet as reaction product only after 18 h. Subsequently, the hybrid material was successfully tested in a photoreactor prototype to treat real polluted air in a wastewater treatment plant. For this purpose, a new tubular photocatalytic reactor that may use solar radiation in combination with artificial radiation was designed; the lamp was turned on when solar UV-A irradiance was below 20 W m(-2), which was observed to be the minimum value to ensure 100% conversion. The efficient distribution of the opaque photocatalyst inside the tubular reactor was achieved by using especially designed star-shaped structures. These structures were employed for the arrangement of groups of eight TiO(2)-SiMgO(x) plates in easy-to-handle channelled units obtaining an adequate flow regime without shading. The prototype continuously removed during one month and under real conditions the H(2)S contained in a 1 L min(-1) air current with a variable inlet concentration in the range of tens of ppmv without release of SO(2).

  9. A model of airflow in the nasal cavities: Implications for nasal air conditioning and epistaxis.

    Science.gov (United States)

    Bailie, Neil; Hanna, Brendan; Watterson, John; Gallagher, Geraldine

    2009-01-01

    A friction force is generated when moving air contacts the nasal walls, referred to as wall shear stress. This interaction facilitates heat and mass transfer between the mucosa and air, i.e., air-conditioning. The objective of this research was to study the distribution of wall shear stress within the nasal cavity to identify areas that contribute significantly to air-conditioning within the nasal cavity. Three-dimensional computational models of the nasal airways of five healthy subjects (three male and two female subjects) were constructed from nasal CT scans. Numerical simulations of nasal airflow were conducted using the commercial computational fluid dynamics code Fluent 6 (Ansys, Inc., Canonsburg, PA). Wall shear stress was derived from the numerical simulation. Air-conditioning was simulated to confirm the relationship with wall shear stress. Nasal airflow simulations predicted high wall shear stress along the anterior aspect of the inferior turbinate, the anteroinferior aspect of the middle turbinate, and within Little's area. The airflow simulations indicate that the inferior and middle turbinates and Little's area on the anterior nasal septum contribute significantly to nasal air-conditioning. The concentration of wall shear stress within Little's area indicates a desiccating and potentially traumatic effect of inhaled air that may explain the predilection for spontaneous epistaxis at this site.

  10. Crop management in greenhouses: adapting the growth conditions to the plant needs or adapting the plant to the growth conditions?

    NARCIS (Netherlands)

    Marcelis, L.F.M.; Pascale, De S.

    2009-01-01

    Strategies for improving greenhouse crop production should target both developing advanced technological systems and designing improved plants. Based on greenhouse experiments, crop models and biotechnological tools, this paper will discuss the physiology of plant-greenhouse interactions. It is disc

  11. Microbial Gas Generation Under Expected Waste Isolation Pilot Plant Repository Conditions: Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Gillow, J.B.; Francis, A.

    2011-07-01

    Gas generation from the microbial degradation of the organic constituents of transuranic (TRU) waste under conditions expected in the Waste Isolation Pilot Plant (WIPP) was investigated. The biodegradation of mixed cellulosic materials and electron-beam irradiated plastic and rubber materials (polyethylene, polyvinylchloride, hypalon, leaded hypalon, and neoprene) was examined. We evaluated the effects of environmental variables such as initial atmosphere (air or nitrogen), water content (humid ({approx}70% relative humidity, RH) and brine inundated), and nutrient amendments (nitogen phosphate, yeast extract, and excess nitrate) on microbial gas generation. Total gas production was determined by pressure measurement and carbon dioxide (CO{sub 2}) and methane (CH{sub 4}) were analyzed by gas chromatography; cellulose degradation products in solution were analyzed by high-performance liquid chromatography. Microbial populations in the samples were determined by direct microscopy and molecular analysis. The results of this work are summarized.

  12. Isobaric gas and steam. Compressed air storage power plant with heat storage system; Isobares GuD. Druckluftspeicherkraftwerk mit Waermespeicher

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, Lasse; Leithner, Reinhard; Qi, Dawei [Technische Univ. Braunschweig (Germany). Inst. fuer Waerme- und Brennstofftechnik; Grote, Wolfgang; Kastsian, Darya; Moennigmann, Martin [Bochum Univ. (Germany). Lehrstuhl fuer Regelungstechnik und Systemtheorie

    2011-07-01

    The ISACOAST-CC (Isobaric Adiabatic Compressed Air Energy Storage - Combinde Cycle) is a innovative combination of combined cycle power plant, compressed air store and heat store. First calculations show that a storage efficiency of 80 % could be achieved.

  13. 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.

  14. Assessing the genotoxicity of urban air pollutants using two in situ plant bioassays.

    Science.gov (United States)

    Villarini, M; Fatigoni, C; Dominici, L; Maestri, S; Ederli, L; Pasqualini, S; Monarca, S; Moretti, M

    2009-12-01

    Genotoxicity of urban air has been analysed almost exclusively in airborne particulates. We monitored the genotoxic effects of airborne pollutants in the urban air of Perugia (Central Italy). Two plant bioindicators with different genetic endpoints were used: micronuclei in meiotic pollen mother cells using Tradescantia-micronucleus bioassay (Trad-MCN) and DNA damage in nuclei of Nicotiana tabacum leaves using comet assay (Nicotiana-comet). Buds of Tradescantia clone # 4430 and young N. tabacum cv. Xanthi plants were exposed for 24 h at three sites with different pollution levels. One control site (indoor control) was also used. The two bioassays showed different sensitivities toward urban pollutants: Trad-MCN assay was the most sensitive, but DNA damage in N. tabacum showed a better correlation with the pollutant concentrations. In situ biomonitoring of airborne genotoxins using higher plants combined with chemical analysis is thus recommended for characterizing genotoxicity of urban air.

  15. 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.

  16. 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.

  17. Influences of the Indoor Environment on Heat, Air, and Moisture Conditions in the Component

    DEFF Research Database (Denmark)

    Steskens, Paul Wilhelmus Maria Hermanus; Rode, Carsten; Janssen, Hans

    2008-01-01

    Current models to predict heat, air and moisture (HAM) conditions in building components assume uniform boundary conditions, both for the temperature and relative humidity of the air in an indoor space as well as for the heat and moisture surface transfer coefficients. The heat and moisture surface...... and relative humidity in the adjacent air are seldom uniform. In order to obtain a reliable prediction of the HAM conditions in a building component, an accurate description of the indoor (and outdoor) boundary conditions is required. The objective of the present paper is to analyze the influence...... of the variations of the surface transfer coefficients near the surface of a building component on the HAM conditions in the component. A parameter study has been used to investigate this influence. The research showed that the surface transfer coefficients have a relatively large influence on the redicted HAM...

  18. Can ornamental potted plants remove volatile organic compounds from indoor air? A review.

    Science.gov (United States)

    Dela Cruz, Majbrit; Christensen, Jan H; Thomsen, Jane Dyrhauge; Müller, Renate

    2014-12-01

    Volatile organic compounds (VOCs) are found in indoor air, and many of these can affect human health (e.g. formaldehyde and benzene are carcinogenic). Plants affect the levels of VOCs in indoor environments, thus they represent a potential green solution for improving indoor air quality that at the same time can improve human health. This article reviews scientific studies of plants' ability to remove VOCs from indoor air. The focus of the review is on pathways of VOC removal by the plants and factors affecting the efficiency and rate of VOC removal by plants. Laboratory based studies indicate that plant induced removal of VOCs is a combination of direct (e.g. absorption) and indirect (e.g. biotransformation by microorganisms) mechanisms. They also demonstrate that plants' rate of reducing the level of VOCs is influenced by a number of factors such as plant species, light intensity and VOC concentration. For instance, an increase in light intensity has in some studies been shown to lead to an increase in removal of a pollutant. Studies conducted in real-life settings such as offices and homes are few and show mixed results.

  19. Impacts of flare emissions from an ethylene plant shutdown to regional air quality

    Science.gov (United States)

    Wang, Ziyuan; Wang, Sujing; Xu, Qiang; Ho, Thomas

    2016-08-01

    Critical operations of chemical process industry (CPI) plants such as ethylene plant shutdowns could emit a huge amount of VOCs and NOx, which may result in localized and transient ozone pollution events. In this paper, a general methodology for studying dynamic ozone impacts associated with flare emissions from ethylene plant shutdowns has been developed. This multi-scale simulation study integrates process knowledge of plant shutdown emissions in terms of flow rate and speciation together with regional air-quality modeling to quantitatively investigate the sensitivity of ground-level ozone change due to an ethylene plant shutdown. The study shows the maximum hourly ozone increments can vary significantly by different plant locations and temporal factors including background ozone data and solar radiation intensity. It helps provide a cost-effective air-quality control strategy for industries by choosing the optimal starting time of plant shutdown operations in terms of minimizing the induced ozone impact (reduced from 34.1 ppb to 1.2 ppb in the performed case studies). This study provides valuable technical supports for both CPI and environmental policy makers on cost-effective air-quality controls in the future.

  20. Antifreeze proteins enable plants to survive in freezing conditions

    Indian Academy of Sciences (India)

    Ravi Gupta; Renu Deswal

    2014-12-01

    Overwintering plants secrete antifreeze proteins (AFPs) to provide freezing tolerance. These proteins bind to and inhibit the growth of ice crystals that are formed in the apoplast during subzero temperatures. Antifreeze activity has been detected in more than 60 plants and AFPs have been purified from 15 of these, including gymnosperms, dicots and monocots. Biochemical characterization of plant antifreeze activity, as determined by the high ice recrystallization inhibition (IRI) activities and low thermal hysteresis (TH) of AFPs, showed that their main function is inhibition of ice crystal growth rather than the lowering of freezing temperatures. However, recent studies showed that antifreeze activity with higher TH also exists in plants. Calcium and hormones like ethylene and jasmonic acid have been shown to regulate plant antifreeze activity. Recent studies have shown that plant AFPs bind to both prism planes and basal planes of ice crystals by means of two flat ice binding sites. Plant AFPs have been postulated to evolve from the OsLRR-PSR gene nearly 36 million years ago. In this review, we present the current scenario of plant AFP research in order to understand the possible potential of plant AFPs in generation of freezing-tolerant crops.

  1. Application of acoustic agglomeration to enhance air filtration efficiency in air-conditioning and mechanical ventilation (ACMV) systems.

    Science.gov (United States)

    Ng, Bing Feng; Xiong, Jin Wen; Wan, Man Pun

    2017-01-01

    The recent episodes of haze in Southeast Asia have caused some of the worst regional atmospheric pollution ever recorded in history. In order to control the levels of airborne fine particulate matters (PM) indoors, filtration systems providing high PM capturing efficiency are often sought, which inadvertently also results in high airflow resistance (or pressure drop) that increases the energy consumption for air distribution. A pre-conditioning mechanism promoting the formation of particle clusters to enhance PM capturing efficiency without adding flow resistance in the air distribution ductwork could provide an energy-efficient solution. This pre-conditioning mechanism can be fulfilled by acoustic agglomeration, which is a phenomenon that promotes the coagulation of suspended particles by acoustic waves propagating in the fluid medium. This paper discusses the basic mechanisms of acoustic agglomeration along with influencing factors that could affect the agglomeration efficiency. The feasibility to apply acoustic agglomeration to improve filtration in air-conditioning and mechanical ventilation (ACMV) systems is investigated experimentally in a small-scale wind tunnel. Experimental results indicate that this novel application of acoustic pre-conditioning improves the PM2.5 filtration efficiency of the test filters by up to 10% without introducing additional pressure drop. The fan energy savings from not having to switch to a high capturing efficiency filter largely outstrip the additional energy consumed by the acoustics system. This, as a whole, demonstrates potential energy savings from the combined acoustic-enhanced filtration system without compromising on PM capturing efficiency.

  2. HOT AIR TREATMENT, IN NATURAL CONVECTION CONDITIONS, FOR EGG SURFACE DECONTAMINATION

    Directory of Open Access Journals (Sweden)

    Chiara Cevoli

    2012-06-01

    Full Text Available In order to improve the animal welfare, the Council Directive 1999/74/EC (defining minimum standards for the welfare of laying hens will ban conventional cage systems from 2012, in favor of enriched cages or floor systems. As a consequence an increased risk of bacterial contamination of eggshells is expected. This has lead toward the development of efficient techniques to reduce eggshell contamination by bacterial pathogens, and thus to prevent any potential or additional food safety risk for Human health. The objectives of this research were to develop and validate a numerical model useful to study the physics of treatment with hot air, in natural convection conditions, and then to assess the impact of the treatment on egg quality and Salmonella Enteritidis inactivation on the shell. As regards the decontamination effectiveness, a reduction in microbial load up to 2.6 log10 after 200 minutes was observed. A linear correlation between the time of treatment and the microbial decimal reduction (R2 0.92 was also observed. This suggests the opportunity of further study with longer treatment. Moreover the results about weak action on quality parameters suggest the practical feasibility of a transportation system for eggs, from production to sorting plant, in heated container.

  3. 复合式空调系统空调期特性的模拟研究%Air conditioning period characteristic simulation of compound air conditioning system

    Institute of Scientific and Technical Information of China (English)

    齐卫阳; 王令; 胥海伦; 钟星灿

    2012-01-01

    针对不同地区的水文地质条件和气象参数,运用SES软件对复合式空调系统进行了数值模拟.运用曲线拟合方法总结了温度临界点的经验公式并且对影响空调期的各因素进行了定性分析.通过正交试验对影响空调期的各因素进行了显著性评价.%For different hydrogeologic conditions and meteorological parameters in different regions, carries out numerical simulation of the compound air conditioning system based on SES software. Summaries the empirical formula of critical point temperature and performs a qualitative analysis of affecting factors of air conditioning period using the curve fitting method. An orthogonal test is made to evaluate the significance of affecting factors of the air conditioning period.

  4. Fungal colonization of air filters for use in heating, ventilating, and air conditioning (HVAC) systems.

    Science.gov (United States)

    Simmons, R B; Crow, S A

    1995-01-01

    New and used cellulosic air filters for HVAC systems including those treated with antimicrobials were suspended in vessels with a range of relative humidities (55-99%) and containing non-sterile potting soil which stimulates fungal growth. Most filters yielded fungi prior to suspension in the chambers but only two of 14 nontreated filters demonstrated fungal colonization following use in HVAC systems. Filters treated with antimicrobials, particularly a phosphated amine complex, demonstrated markedly less fungal colonization than nontreated filters. In comparison with nontreated cellulosic filters, fungal colonization of antimicrobial-treated cellulosic filters was selective and delayed.

  5. Effect of Harvest of Air Relative Humidity on Water and Heat Transfer in Soil With Crops Under Arid Climatic Conditions

    Directory of Open Access Journals (Sweden)

    El Khadir LAKHAL

    2015-05-01

    Full Text Available In this work, the main objective is to analyze the effect of the harvest of air relative humidity on soil temperature, soil water storage and evaporation. An experiment work was conducted in order to evaluate the quantity of soil water adsorbed by harvesting of relative air humidity. This experimental work was conducted on hilly areas with various hypsographic and microclimatic conditions greatly affecting daily fluctuations of air humidity and soil characteristics. The metrological data needed by SISPAT model were obtained by using a Campbell Scientific equipments Station recorder on data loggers every half hour. A numerical model based on SiSPAT (Système d’Interaction Sol Plante Atmosphère formulation is adopted. The general equations of the proposed model are based on heat and mass transfer in the soil, atmosphere and plant system. This study shows that Soil Water Adsorption (SWA induce an increasing in the total evaporation and in soil water storage especially on the upper layers. The effect of Soil Water Adsorption on soil temperature appears for the first layers of soil and become absent in the profound zone because the vapour condensation phenomenon is very important at night for the first layers.

  6. Plant injury by air pollutants: influence of humidity on stomatal apertures and plant response to ozone.

    Science.gov (United States)

    Otto, H W; Daines, R H

    1969-03-14

    Ozone injury to Bel W3 tobacco and pinto bean plants increases with increasing humidity. The degree of plant injury sustained correlates well with porometer measurements; this indicates that the size of stomatal apertures increases with increasing humidity. Humidity may therefore influence plant response to all pollutants and may account in part for the greater sensitivity of plants to ozone-type injury in the eastern United States compared with the same species of plants grown in the Southwest. with those grown in the Southwest.

  7. The influence of variable operating conditions on the design and exploitation of fly ash pneumatic transport systems in thermal power plants

    Directory of Open Access Journals (Sweden)

    M. Stanojević

    2008-12-01

    Full Text Available The efficiency of an air-slide pneumatic conveying system depends, first of all, on several basic elements chosen or calculated during the design of a plant: air-slide design parameters, air mover characteristics, as well as the physical and chemical properties of the material to be transported. However, during the exploitation of this type of system which is used for handling ash in thermal-power plants, either gradual and/or sudden changes in the operating conditions can arise. This may be due to changes both in the proportion of ash content, and in the flow characteristics of the porous membrane. The consequences of changes in these conditions on the performance of the ash handling system are analyzed, based upon the results of the experimental work carried out on the test rig at the Faculty of Mechanical Engineering in Belgrade, and upon the on-site measurements at the thermal-power plant "Nikola Tesla B".

  8. Different survival strategies amongst plants to cope with underwater conditions

    NARCIS (Netherlands)

    Van Veen, Hans; Vashisht, Divya; Voesenek, Laurentius A C J; Sasidharan, Rashmi

    2014-01-01

    Many plants experience flooding at some point during their life cycle. The underwater environment creates a carbon and energy crisis for the plant, for which two successful strategies have been identified, quiescence and escape. During quiescence, growth is actively reduced until the water levels re

  9. 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.

  10. Design and performance of a solar-powered air-conditioning system in a green building

    Energy Technology Data Exchange (ETDEWEB)

    Zhai, X.Q.; Wang, R.Z.; Wu, J.Y.; Dai, Y.J.; Ma, Q. [Institute of Refrigeration and Cryogenics, Shanghai Jiao Tong University, Shanghai 200030 (China)

    2008-05-15

    A solar-powered adsorption air-conditioning system was designed and installed in the green building of Shanghai Research Institute of Building Science. The system contained 150 m{sup 2} solar collectors and two adsorption chillers with nominal refrigeration capacity of 8.5 kW. Based on performance characteristics of the adsorption chiller, the operation mode of the solar-powered air-conditioning system was optimized by maintaining a phase shift of 540 s between the two adsorption chillers. Thereafter, the whole system realized stable operation by the balance of heat consumption and refrigeration output. From June to August of 2005, the solar-powered air-conditioning system continuously ran between 9:00 and 17:00. The operation performance of the system under representative working condition showed that the average refrigeration output of the solar-powered air-conditioning system was 15.3 kW during an 8 h operation and the maximum value exceeded 20 kW. Solar fraction for the system in summer was 71.7%, which corresponded to the designed cooling load (15 kW). Compared with the ambient temperature, it was deduced that solar radiant intensity had a more distinct influence on the performance of solar-powered air-conditioning system. (author)

  11. Improving forecast skill by assimilation of quality-controlled AIRS temperature retrievals under partially cloudy conditions

    Science.gov (United States)

    Reale, O.; Susskind, J.; Rosenberg, R.; Brin, E.; Liu, E.; Riishojgaard, L. P.; Terry, J.; Jusem, J. C.

    2008-04-01

    The National Aeronautics and Space Administration (NASA) Atmospheric Infrared Sounder (AIRS) on board the Aqua satellite is now recognized as an important contributor towards the improvement of weather forecasts. At this time only a small fraction of the total data produced by AIRS is being used by operational weather systems. In fact, in addition to effects of thinning and quality control, the only AIRS data assimilated are radiance observations of channels unaffected by clouds. Observations in mid-lower tropospheric sounding AIRS channels are assimilated primarily under completely clear-sky conditions, thus imposing a very severe limitation on the horizontal distribution of the AIRS-derived information. In this work it is shown that the ability to derive accurate temperature profiles from AIRS observations in partially cloud-contaminated areas can be utilized to further improve the impact of AIRS observations in a global model and forecasting system. The analyses produced by assimilating AIRS temperature profiles obtained under partial cloud cover result in a substantially colder representation of the northern hemisphere lower midtroposphere at higher latitudes. This temperature difference has a strong impact, through hydrostatic adjustment, in the midtropospheric geopotential heights, which causes a different representation of the polar vortex especially over northeastern Siberia and Alaska. The AIRS-induced anomaly propagates through the model's dynamics producing improved 5-day forecasts.

  12. Improving Forecast Skill by Assimilation of Quality-controlled AIRS Temperature Retrievals under Partially Cloudy Conditions

    Science.gov (United States)

    Reale, O.; Susskind, J.; Rosenberg, R.; Brin, E.; Riishojgaard, L.; Liu, E.; Terry, J.; Jusem, J. C.

    2007-01-01

    The National Aeronautics and Space Administration (NASA) Atmospheric Infrared Sounder (AIRS) on board the Aqua satellite has been long recognized as an important contributor towards the improvement of weather forecasts. At this time only a small fraction of the total data produced by AIRS is being used by operational weather systems. In fact, in addition to effects of thinning and quality control, the only AIRS data assimilated are radiance observations of channels unaffected by clouds. Observations in mid-lower tropospheric sounding AIRS channels are assimilated primarily under completely clear-sky conditions, thus imposing a very severe limitation on the horizontal distribution of the AIRS-derived information. In this work it is shown that the ability to derive accurate temperature profiles from AIRS observations in partially cloud-contaminated areas can be utilized to further improve the impact of AIRS observations in a global model and forecasting system. The analyses produced by assimilating AIRS temperature profiles obtained under partial cloud cover result in a substantially colder representation of the northern hemisphere lower midtroposphere at higher latitudes. This temperature difference has a strong impact, through hydrostatic adjustment, in the midtropospheric geopotential heights, which causes a different representation of the polar vortex especially over northeastern Siberia and Alaska. The AIRS-induced anomaly propagates through the model's dynamics producing improved 5-day forecasts.

  13. Evaluating the fate of metals in air pollution control residues from coal-fired power plants.

    Science.gov (United States)

    Thorneloe, Susan A; Kosson, David S; Sanchez, Florence; Garrabrants, Andrew C; Helms, Gregory

    2010-10-01

    Changes in emissions control at U.S. coal-fired power plants will shift metals content from the flue gas to the air pollution control (APC) residues. To determine the potential fate of metals that are captured through use of enhanced APC practices, the leaching behavior of 73 APC residues was characterized following the approach of the Leaching Environmental Assessment Framework. Materials were tested over pH conditions and liquid-solid ratios expected during management via land disposal or beneficial use. Leachate concentrations for most metals were highly variable over a range of coal rank, facility configurations, and APC residue types. Liquid-solid partitioning (equilibrium) as a function of pH showed significantly different leaching behavior for similar residue types and facility configurations. Within a facility, the leaching behavior of blended residues was shown to follow one of four characteristic patterns. Variability in metals leaching was greater than the variability in totals concentrations by several orders of magnitude, inferring that total content is not predictive of leaching behavior. The complex leaching behavior and lack of correlation to total contents indicates that release evaluation under likely field conditions is a better descriptor of environmental performance than totals content or linear partitioning approaches.

  14. Supplemental site inspection for Air Force Plant 59, Johnson City, New York, Volume 1: Investigation report

    Energy Technology Data Exchange (ETDEWEB)

    Nashold, B.; Rosenblatt, D.; Hau, J. [and others

    1995-08-01

    This summary describes a Supplemental Site Inspection (SSI) conducted by Argonne National Laboratory (ANL) at Air Force Plant 59 (AFP 59) in Johnson City, New York. All required data pertaining to this project were entered by ANL into the Air Force-wide Installation Restoration Program Information System (IRPIMS) computer format and submitted to an appropriate authority. The work was sponsored by the United States Air Force as part of its Installation Restoration Program (IRP). Previous studies had revealed the presence of contaminants at the site and identified several potential contaminant sources. Argonne`s study was conducted to answer questions raised by earlier investigations.

  15. Air pollution by 3,4-benzpyrene in the vicinity of petrochemical plants

    Energy Technology Data Exchange (ETDEWEB)

    Samoilovich, L.N.

    1968-01-01

    Air samples were collected on filters and the filters were extracted with benzene; after evaporation of the benzene, the dry extract was dissolved in n-octane. The 3,4-benzpyrene (BP) concentration was determined by fluorescent spectroscopy at -196/sup 0/C; preliminary chromatographic fractionation of the extract could be omitted by quantitative analysis of BP according to the intensity of its fluorescence at 4030 Angstroms. The BP concentration in air samples collected in various areas around the Grozny petrochemical plant was 0.1 to 400 microg/100 m3 air; the highest levels were seen in samples collected near the areas where petroleum products were processed at high temperatures.

  16. House-plant placement for indoor air purification and health benefits on asthmatics

    OpenAIRE

    2014-01-01

    Objectives Some plants were placed in indoor locations frequented by asthmatics in order to evaluate the quality of indoor air and examine the health benefits to asthmatics. Methods The present study classified the participants into two groups: households of continuation and households of withdrawal by a quasi-experimental design. The households of continuation spent the two observation terms with indoor plants, whereas the households of withdrawal passed the former observation terms with ind...

  17. Evolutionary relationships can be more important than abiotic conditions in predicting the outcome of plant-plant interactions

    Science.gov (United States)

    Soliveres, Santiago; Torices, Rubén; Maestre, Fernando T.

    2015-01-01

    Positive and negative plant-plant interactions are major processes shaping plant communities. They are affected by environmental conditions and evolutionary relationships among the interacting plants. However, the generality of these factors as drivers of pairwise plant interactions and their combined effects remain virtually unknown. We conducted an observational study to assess how environmental conditions (altitude, temperature, irradiance and rainfall), the dispersal mechanism of beneficiary species and evolutionary relationships affected the co-occurrence of pairwise interactions in 11 Stipa tenacissima steppes located along an environmental gradient in Spain. We studied 197 pairwise plant-plant interactions involving the two major nurse plants (the resprouting shrub Quercus coccifera and the tussock grass S. tenacissima) found in these communities. The relative importance of the studied factors varied with the nurse species considered. None of the factors studied were good predictors of the co-ocurrence between S. tenacissima and its neighbours. However, both the dispersal mechanism of the beneficiary species and the phylogenetic distance between interacting species were crucial factors affecting the co-occurrence between Q. coccifera and its neighbours, while climatic conditions (irradiance) played a secondary role. Values of phylogenetic distance between 207-272.8 Myr led to competition, while values outside this range or fleshy-fruitness in the beneficiary species led to positive interactions. The low importance of environmental conditions as a general driver of pairwise interactions was caused by the species-specific response to changes in either rainfall or radiation. This result suggests that factors other than climatic conditions must be included in theoretical models aimed to generally predict the outcome of plant-plant interactions. Our study helps to improve current theory on plant-plant interactions and to understand how these interactions can

  18. Model Based Sensor System for Temperature Measurement in R744 Air Conditioning Systems

    CERN Document Server

    Reitz, Sven; Schneider, Peter

    2008-01-01

    The goal is the development of a novel principle for the temperature acquisition of refrigerants in CO2 air conditioning systems. The new approach is based on measuring the temperature inside a pressure sensor, which is also needed in the system. On the basis of simulative investigations of different mounting conditions functional relations between measured and medium temperature will be derived.

  19. Dynamic Analysis of Condenser Assembly of Automobile Air Conditioning System Using CAE Tools

    Science.gov (United States)

    Singh, M.; Singh, D.; Saini, J. S.

    2013-04-01

    With the automotive air-conditioning industry aiming at higher levels of quality, cost effectiveness and a short time to market, the need for simulation is at an all time high. In the present work, the use of dynamics analysis is proposed in the simulation of the automobile air conditioning condenser assembly for the vibration loads. The condenser assembly has been analyzed using the standard testing conditions. The results revealed that the components of condenser assembly may fail due to resonance in dynamic analysis. Thereafter, the condenser assembly was optimized, resulting in a 2 % reduction in mass.

  20. Effects of plant-soil feedback on tree seedling growth under arid conditions

    NARCIS (Netherlands)

    Meijer, S.S.; Holmgren, M.; Putten, van der W.H.

    2011-01-01

    Aims: Plants are able to influence their growing environment by changing biotic and abiotic soil conditions. These soil conditions in turn can influence plant growth conditions, which is called plant–soil feedback. Plant–soil feedback is known to be operative in a wide variety of ecosystems ranging

  1. Numerical Analysis on Ventilating and Air Conditioning Scheme of Shenyang Subway Station

    Institute of Scientific and Technical Information of China (English)

    LI Wei; NA Yanling

    2007-01-01

    Different cities have different climate conditions and outdoor temperature and humidity, so the scheme of an environment control in subway should be analyzed by considering objective conditions, project cost and operating status. In this paper, a physical and mathematical model is built according to the design of Shenyang subway (line 1), the boundary conditions of the model are defined by the design and experiments, the numerical analysis of ventilating scheme and air conditioning scheme is introduced individually, and the temperature field and air flow field of the two schemes are compared, so that the feasibility of using a ventilating scheme in subway of northeast cities is discussed. Considering comfort and economy, it can be concluded that mechanical ventilation is feasible in subway of northeast cities because the air temperature there is not very high in summer.

  2. OPTIMIZATION OF MICROWAVE AND AIR DRYING CONDITIONS OF QUINCE (CYDONIA OBLONGA, MILLER USING RESPONSE SURFACE METHODOLOGY

    Directory of Open Access Journals (Sweden)

    Cem Baltacioglu

    2015-03-01

    Full Text Available Effects of slice thickness of quince (Cydonia oblonga Miller , microwave incident power and air drying temperature on antioxidant activity and total phenolic content of quince were investigated during drying in microwave and air drying. Optimum conditions were found to be: i for microwave drying, 285 W and 4.14 mm thick (maximum antioxidant activity and 285 W and 6.85 mm thick (maximum total phenolic content, and ii for air drying, 75 ºC and 1.2 mm thick (both maximum antioxidant activity and total phenolic content. Drying conditions were optimized by using the response surface methodology. 13 experiments were carried out considering incident microwave powers from 285 to 795 W, air temperature from 46 to 74 ºC and slice thickness from 1.2 to 6.8 mm.

  3. Robustness analysis of an air heating plant and control law by using polynomial chaos

    Energy Technology Data Exchange (ETDEWEB)

    Colón, Diego [University of São Paulo, Polytechnic School, LAC -PTC, São Paulo (Brazil); Ferreira, Murillo A. S.; Bueno, Átila M. [São Paulo State University - Sorocaba Campus, Sorocaba (Brazil); Balthazar, José M. [São Paulo State University - Rio Claro Campus, Rio Claro (Brazil); Rosa, Suélia S. R. F. de [University of Brasilia, Brasilia (Brazil)

    2014-12-10

    This paper presents a robustness analysis of an air heating plant with a multivariable closed-loop control law by using the polynomial chaos methodology (MPC). The plant consists of a PVC tube with a fan in the air input (that forces the air through the tube) and a mass flux sensor in the output. A heating resistance warms the air as it flows inside the tube, and a thermo-couple sensor measures the air temperature. The plant has thus two inputs (the fan's rotation intensity and heat generated by the resistance, both measured in percent of the maximum value) and two outputs (air temperature and air mass flux, also in percent of the maximal value). The mathematical model is obtained by System Identification techniques. The mass flux sensor, which is nonlinear, is linearized and the delays in the transfer functions are properly approximated by non-minimum phase transfer functions. The resulting model is transformed to a state-space model, which is used for control design purposes. The multivariable robust control design techniques used is the LQG/LTR, and the controllers are validated in simulation software and in the real plant. Finally, the MPC is applied by considering some of the system's parameters as random variables (one at a time, and the system's stochastic differential equations are solved by expanding the solution (a stochastic process) in an orthogonal basis of polynomial functions of the basic random variables. This method transforms the stochastic equations in a set of deterministic differential equations, which can be solved by traditional numerical methods (That is the MPC). Statistical data for the system (like expected values and variances) are then calculated. The effects of randomness in the parameters are evaluated in the open-loop and closed-loop pole's positions.

  4. Minor contributions of the maxillary sinus to the air-conditioning performance in macaque monkeys.

    Science.gov (United States)

    Mori, Futoshi; Hanida, Sho; Kumahata, Kiyoshi; Miyabe-Nishiwaki, Takako; Suzuki, Juri; Matsuzawa, Teruo; Nishimura, Takeshi D

    2015-08-01

    The nasal passages mainly adjust the temperature and humidity of inhaled air to reach the alveolar condition required in the lungs. By contrast to most other non-human primates, macaque monkeys are distributed widely among tropical, temperate and subarctic regions, and thus some species need to condition the inhaled air in cool and dry ambient atmospheric areas. The internal nasal anatomy is believed to have undergone adaptive modifications to improve the air-conditioning performance. Furthermore, the maxillary sinus (MS), an accessory hollow communicating with the nasal cavity, is found in macaques, whereas it is absent in most other extant Old World monkeys, including savanna monkeys. In this study, we used computational fluid dynamics simulations to simulate the airflow and heat and water exchange over the mucosal surface in the nasal passage. Using the topology models of the nasal cavity with and without the MS, we demonstrated that the MS makes little contribution to the airflow pattern and the air-conditioning performance within the nasal cavity in macaques. Instead, the inhaled air is conditioned well in the anterior portion of the nasal cavity before reaching the MS in both macaques and savanna monkeys. These findings suggest that the evolutionary modifications and coetaneous variations in the nasal anatomy are rather independent of transitions and variations in the climate and atmospheric environment found in the habitats of macaques. © 2015. Published by The Company of Biologists Ltd.

  5. Simulation and Optimization of a Solar Driven Air Conditioning System for Indian Cities

    OpenAIRE

    Sharma, Dev

    2013-01-01

    Simulation and Optimization of a Solar Driven Air Conditioning System for Indian Cities Conventional air-conditioners need high grade energy i.e. electricity, which in India, is primarily produced from fossil fuels. In spite of several emission restraints exercised by many countries under Kyoto protocol, energy consumption and pollution levels are higher than ever. Therefore, an assessment from the ecological point of view needs to be implemented as the greenhouse gases effect remains a threa...

  6. Innovative conditioning of groundwater as a prerequisite for an efficient air-conditioning of buildings by means of near-surface geothermal energy; Innovative Grundwasseraufbereitung als Voraussetzung fuer eine effiziente Gebaeudeklimatisierung durch die Nutzung oberflaechennaher Geothermie

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, C.; Krauss, M.; Steinmetz, H. [Stuttgart Univ. (Germany). Inst. fuer Siedlungswasserbau-, Wasserguete- und Abfallwirtschaft; Edel, H.G.; Kellner, C. [Zueblin Umwelttechnik GmbH (Germany)

    2012-10-16

    The air-conditioning of buildings increasingly requires alternatives to cover the energy demand from renewable energy sources. One possibility consists of the utilization of a heat pump fed with ground water. Due to the local hydrogeochemical realities, groundwater however contains large amounts of solved iron and manganese resulting in operational problems (depositions) in plant sections. Without a previous conditioning, such waters cannot be utilized. Under this aspect, the authors of the contribution under consideration report on the technology of an in-situ conditioning of groundwater as an innovative conditioning process to remove iron and manganese enabling an efficient air-conditioning of buildings by utilizing sub-surface geothermal energy (groundwater). The process is characterized by numerous advantages such as the absence of residues from processing residues compared with conventional conditioning procedures. Beside the description of the procedure, plant engineering as well as the planning fundamentals, the authors of the contribution under consideration present the in-situ-conditioning of groundwater for the air-conditioning of the buildings of the Berufsakademie Hohenheim (Baden-Wueerttemberg, Federal Republic of Germany) as a case study.

  7. Air-conditioned university laboratories: Comparing CO2 measurement for centralized and split-unit systems

    Directory of Open Access Journals (Sweden)

    M. Hussin

    2017-04-01

    Full Text Available Universities are designed for higher education learning, and improving university indoor air quality (IAQ is essential to the enhanced performances of students and staff members alike. The majority of IAQ problems are due to inadequate ventilation in university buildings. Carbon Dioxide (CO2 measurements have become a commonly used screening test of IAQ because measurement levels can be used to evaluate the amount of ventilation and general comfort. This paper examines CO2 field measurement for undergraduate practical classes. Ten air conditioned laboratories with ventilation were chosen for CO2 field measurement. CO2 was monitored under indoor and outdoor conditions. Indoor CO2 concentration for Laboratories 1 and 10 is observed to be higher than 1000 ppm which indicated inadequate ventilation, while other laboratories showed CO2 concentrations less than 1000 ppm. Air capacity and outdoor air were calculated based on the design documentation. A comparison between design and actual outdoor air/person values indicates that the air conditioning systems of the laboratories had adequate ventilation.

  8. Phenological mismatch with abiotic conditions implications for flowering in Arctic plants.

    Science.gov (United States)

    Wheeler, Helen C; Høye, Toke T; Schmidt, Niels Martin; Svenning, Jens-Christian; Forchhammer, Mads C

    2015-03-01

    Although many studies have examined the phenological mismatches between interacting organisms, few have addressed the potential for mismatches between phenology and seasonal weather conditions. In the Arctic, rapid phenological changes in many taxa are occurring in association with earlier snowmelt. The timing of snowmelt is jointly affected by the size of the late winter snowpack and the temperature during the spring thaw. Increased winter snowpack results in delayed snowmelt, whereas higher air temperatures and faster snowmelt advance the timing of snowmelt. Where interannual variation in snowpack is substantial, changes in the timing of snowmelt can be largely uncoupled from changes in air temperature. Using detailed, long-term data on the flowering phenology of four arctic plant species from Zackenberg, Greenland, we investigate whether there is a phenological component to the temperature conditions experienced prior to and during flowering. In particular, we assess the role of timing of flowering in determining pre-flowering exposure to freezing temperatures and to the temperatures-experienced prior to flowering. We then examine the implications of flowering phenology for flower abundance. Earlier snowmelt resulted in greater exposure to freezing conditions, suggesting an increased potential for a mismatch between the timing of flowering and seasonal weather conditions and an increased potential for negative consequences, such as freezing 'damage. We also found a parabolic relationship between the timing of flowering and the temperature experienced during flowering after taking interannual temperature effects into account. If timing of flowering advances to a cooler period of the growing season, this may moderate the effects of a general warming trend across years. Flower abundance was quadratically associated with the timing of flowering, such that both early and late flowering led to lower flower abundance than did intermediate flowering. Our results

  9. The covariance of air quality conditions in six cities in Southern Germany - The role of meteorology.

    Science.gov (United States)

    Dimitriou, Konstantinos; Kassomenos, Pavlos

    2017-01-01

    This paper analyzed air quality in six cities in Southern Germany (Ulm, Augsburg, Konstanz, Freiburg, Stuttgart and Munich), in conjunction with the prevailing synoptic conditions. Air quality was estimated through the calculation of a daily Air Stress Index (ASI) constituted by five independent components, each one expressing the contribution of one of the five main pollutants (PM10, O3, SO2, NO2 and CO) to the total air stress. As it was deduced from ASI components, PM10 from combustion sources and photochemically produced tropospheric O3 are the most hazardous pollutants at the studied sites, throughout cold and warm periods respectively, yet PM10 contribute substantially to the overall air stress during both seasons. The influence of anticyclonic high pressure systems, leading to atmospheric stagnation, was associated with increased ASI values, mainly due to the entrapment of PM10. Moderate air stress was generally estimated in all cities however a cleaner atmosphere was detected principally in Freiburg when North Europe was dominated by low pressure systems. Daily events of notably escalated ASI values were further analyzed with backward air mass trajectories. Throughout cold period, ASI episodes were commonly related to eastern airflows carrying exogenous PM10 originated from eastern continental Europe. During warm period, ASI episodes were connected to the arrival of regionally circulated air parcels reflecting lack of dispersion and accumulation of pollutants in accordance with the synoptic analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Thermal sensation of Hong Kong people with increased air speed, temperature and humidity in air-conditioned environment

    Energy Technology Data Exchange (ETDEWEB)

    Chow, T.T. [School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Kowloon, Hong Kong SAR (China); Fong, K.F.; Lin, Zhang; Chan, A.L.S. [Division of Building Science and Technology, College of Science and Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Kowloon, Hong Kong SAR (China); Givoni, B. [Department of Architecture, UCLA, Los Angeles, CA (United States); BGU, Beer Sheva (Israel)

    2010-10-15

    In the warm and humid climate zone, air-conditioning (AC) is usually provided at working places to enhance human thermal comfort and work productivity. From the building sustainability point of view, to achieve acceptable thermal sensation with the minimum use of energy can be desirable. A new AC design tactic is then to increase the air movement so that the summer temperature setting can be raised. A laboratory-based thermal comfort survey was conducted in Hong Kong with around 300 educated Chinese subjects. Their thermal sensation votes were gathered for a range of controlled thermal environment. The result analysis shows that, like in many other Asian cities, the thermal sensation of the Hong Kong people is sensitive to air temperature and speed, but not much to humidity. With bodily air speed at 0.1-0.2 m/s, clothing level 0.55 clo and metabolic rate 1 met, the neutral temperature was found around 25.4 C for sedentary working environment. Then recommendations are given to the appropriate controlled AC environment in Hong Kong with higher airflow speeds. (author)

  11. Biological effects of plant residues with contrasting chemical compositions on plant and soil under humid tropical conditions.

    NARCIS (Netherlands)

    Tian, G.

    1992-01-01

    A study on plant residues with contrasting chemical compositions was conducted under laboratory, growth chamber and humid tropical field conditions to understand the function of the soil fauna in the breakdown of plant residues, the cycling of nutrients, in particular nitrogen, and the performance o

  12. Assessing the genotoxicity of urban air pollutants using two in situ plant bioassays

    Energy Technology Data Exchange (ETDEWEB)

    Villarini, M.; Fatigoni, C.; Dominici, L.; Maestri, S. [Department of Medical-Surgical Specialties and Public Health, University of Perugia, I-06126 (Italy); Ederli, L.; Pasqualini, S. [Department of Applied Biology, University of Perugia, I-06121 (Italy); Monarca, S. [Department of Medical-Surgical Specialties and Public Health, University of Perugia, I-06126 (Italy); Moretti, M., E-mail: massimo.moretti@unipg.i [Department of Medical-Surgical Specialties and Public Health, University of Perugia, I-06126 (Italy)

    2009-12-15

    Genotoxicity of urban air has been analysed almost exclusively in airborne particulates. We monitored the genotoxic effects of airborne pollutants in the urban air of Perugia (Central Italy). Two plant bioindicators with different genetic endpoints were used: micronuclei in meiotic pollen mother cells using Tradescantia-micronucleus bioassay (Trad-MCN) and DNA damage in nuclei of Nicotiana tabacum leaves using comet assay (Nicotiana-comet). Buds of Tradescantia clone no. 4430 and young N. tabacum cv. Xanthi plants were exposed for 24 h at three sites with different pollution levels. One control site (indoor control) was also used. The two bioassays showed different sensitivities toward urban pollutants: Trad-MCN assay was the most sensitive, but DNA damage in N. tabacum showed a better correlation with the pollutant concentrations. In situ biomonitoring of airborne genotoxins using higher plants combined with chemical analysis is thus recommended for characterizing genotoxicity of urban air. - Plant bioassays used to explore in situ the correlation between air pollution and genotoxicity.

  13. Identification and evaluation of air-pollution-tolerant plants around lignite-based thermal power station for greenbelt development.

    Science.gov (United States)

    Govindaraju, M; Ganeshkumar, R S; Muthukumaran, V R; Visvanathan, P

    2012-05-01

    Thermal power plants emit various gaseous and particulate pollutants into the atmosphere. It is well known that trees help to reduce air pollution. Development of a greenbelt with suitable plant species around the source of emission will mitigate the air pollution. Selection of suitable plant species for a greenbelt is very important. Present study evaluates different plant species around Neyveli thermal power plant by calculating the Air Pollution Tolerance Index (APTI) which is based on their significant biochemical parameters. Also Anticipated Performance Index (API) was calculated for these plant species by combining APTI values with other socio-economic and biological parameters. Based on these indices, the most appropriate plant species were identified for the development of a greenbelt around the thermal power plant to mitigate air pollution. Among the 30 different plant species evaluated, Mangifere indica L. was identified as keystone species which is coming under the excellent category. Ambient air quality parameters were correlated with the biochemical characteristics of plant leaves and significant changes were observed in the plants biochemical characteristics due to the air pollution stress.

  14. Plant response to air pollution by heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, Y.; Mitsuki, H.; Takata, N.

    1975-01-01

    The effect of air pollutants on the concentration of heavy metals in leaves of trees in the neighborhood of a steel factory was studied. Paulownia trees, which absorb and accumulate heavy metals better than other trees, were sampled in the middle of November. The concentration of heavy metals in the soil was measured for every 10 cm vertically downward to a depth of 80 cm near the roots of the sample trees. The concentrations of iron and manganese in the dust were 34.6 to 57.8% and 0.41 to 3.21%, respectively, mainly in oxidized form. The amounts of these metals discharged from the factories were calculated from the concentrations in the atmosphere. Tree leaves in the polluted area were analyzed to determine the route of atmospheric iron from the source to the atmosphere to the soil, where it is absorbed by the roots to accumulate in the leaves. The concentration of Mn in soil exponentially decreases with distance from the source, but its concentration in tree leaves increases with distance. 4 figures.

  15. Air purification in industrial plants producing automotive rubber components in terms of energy efficiency

    Science.gov (United States)

    Grzebielec, Andrzej; Rusowicz, Artur; Szelągowski, Adam

    2017-04-01

    In automotive industry plants, which use injection molding machines for rubber processing, tar contaminates air to such an extent that air fails to enter standard heat recovery systems. Accumulated tar clogs ventilation heat recovery exchangers in just a few days. In the plant in which the research was conducted, tar contamination causes blockage of ventilation ducts. The effect of this phenomenon was that every half year channels had to be replaced with new ones, since the economic analysis has shown that cleaning them is not cost-efficient. Air temperature inside such plants is often, even in winter, higher than 30°C. The air, without any means of heat recovery, is discharged outside the buildings. The analyzed plant uses three types of media for production: hot water, cold water at 14°C (produced in a water chiller), and compressed air, generated in a unit with a rated power consumption of 180 kW. The aim of the study is to determine the energy efficiency improvement of this type of manufacturing plant. The main problem to solve is to provide an air purification process so that air can be used in heat recovery devices. The next problem to solve is to recover heat at such a temperature level that it would be possible to produce cold for technological purposes without air purification. Experimental studies have shown that air purification is feasible. By using one microjet head, a total of 75% of tar particles was removed from the air; by using 4 heads, a purification efficiency of 93% was obtained. This method of air purification causes air temperature to decrease from 35°C to 20°C, which significantly reduces the potential for heat recovery. The next step of the research was designing a cassette-plate heat exchanger to exchange heat without air purification. The economic analysis of such a solution revealed that replacing the heat exchanger with a new one even once a year was not cost-efficient. Another issue examined in the context of energy efficiency was

  16. Air purification in industrial plants producing automotive rubber components in terms of energy efficiency

    Directory of Open Access Journals (Sweden)

    Grzebielec Andrzej

    2017-04-01

    Full Text Available In automotive industry plants, which use injection molding machines for rubber processing, tar contaminates air to such an extent that air fails to enter standard heat recovery systems. Accumulated tar clogs ventilation heat recovery exchangers in just a few days. In the plant in which the research was conducted, tar contamination causes blockage of ventilation ducts. The effect of this phenomenon was that every half year channels had to be replaced with new ones, since the economic analysis has shown that cleaning them is not cost-efficient. Air temperature inside such plants is often, even in winter, higher than 30°C. The air, without any means of heat recovery, is discharged outside the buildings. The analyzed plant uses three types of media for production: hot water, cold water at 14°C (produced in a water chiller, and compressed air, generated in a unit with a rated power consumption of 180 kW. The aim of the study is to determine the energy efficiency improvement of this type of manufacturing plant. The main problem to solve is to provide an air purification process so that air can be used in heat recovery devices. The next problem to solve is to recover heat at such a temperature level that it would be possible to produce cold for technological purposes without air purification. Experimental studies have shown that air purification is feasible. By using one microjet head, a total of 75% of tar particles was removed from the air; by using 4 heads, a purification efficiency of 93% was obtained. This method of air purification causes air temperature to decrease from 35°C to 20°C, which significantly reduces the potential for heat recovery. The next step of the research was designing a cassette-plate heat exchanger to exchange heat without air purification. The economic analysis of such a solution revealed that replacing the heat exchanger with a new one even once a year was not cost-efficient. Another issue examined in the context of

  17. Investigation of solar energy utilization in a novel desiccant based air conditioning system

    Energy Technology Data Exchange (ETDEWEB)

    Hurdodan, Ertac; Buyukalaca, Orhan [Department of Energy Systems Engineering, Faculty of Engineering, Osmaniye Korkut Ata University (Turkey)], email: ehurdogan@osmaniye.edu.tr, email: obuyukalaca@osmaniye.edu.tr; Yilmaz, Tuncay; Uckan, Irfan [Department of Mechanical Engineering, Faculty of Engineering and Architecture, Cukurova University (Turkey)], email: tunyil@cu.edu.tr, email: iuckan@cu.edu.tr; Hepbasli, Arif [Department of Mechanical Engineering, College of Engineering, King Saud University (Saudi Arabia)], email: ahepbasli.c@ksu.edu.sa

    2011-07-01

    Desiccant-based air-conditioning systems are an alternative to traditional air conditioning units. They have superior humidity control and are usually used in health care facilities to reduce the airborne transmission of disease. In the present study, an innovative, desiccant-based air-conditioning system was designed and tested in Cukurova University, Adana, Turkey. A model for investigating the use of solar energy in the system was developed. Experimental temperatures throughout the cooling season of 2008 and solar radiation data, measured by the State Meteorological Affairs (DMI) over the period 1986-2006, were utilized in the model. A comparison was made between the results obtained from the model and those from the experiments and it was concluded that solar energy could be utilized in the system. Solar energy also increased the coefficient of performance (COP) of the system by between 50% and 120% and was shown to be a cost-effective way of regenerating the desiccant.

  18. 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.

  19. An Expert Fault Diagnosis System for Vehicle Air Conditioning Product Development

    Science.gov (United States)

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

    2015-09-01

    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 the problems. In the vehicle air-conditioning manufacturing industry, process can be very costly where an expert and experience personnel needed in certain circumstances. The expert of in the industry will retire or resign from time to time. When the expert is absent, their experience and knowledge is difficult to retrieve or lost forever. Expert system is a convenient method to replace expert. By replacing the expert with expert system, the accuracy of the processes will be increased compared to the conventional way. Therefore, the quality of product services that are produced will be finer and better. The inputs for the fault diagnosis are based on design data and experience of the engineer.

  20. Impact of the electric compressor for automotive air conditioning system on fuel consumption and performance analysis

    Science.gov (United States)

    Zulkifli, A. A.; Dahlan, A. A.; Zulkifli, A. H.; Nasution, H.; Aziz, A. A.; Perang, M. R. M.; Jamil, H. M.; Misseri, M. N.

    2015-12-01

    Air conditioning system is the biggest auxiliary load in a vehicle where the compressor consumed the largest. Problem with conventional compressor is the cooling capacity cannot be control directly to fulfill the demand of thermal load inside vehicle cabin. This study is conducted experimentally to analyze the difference of fuel usage and air conditioning performance between conventional compressor and electric compressor of the air conditioning system in automobile. The electric compressor is powered by the car battery in non-electric vehicle which the alternator will recharge the battery. The car is setup on a roller dynamometer and the vehicle speed is varied at 0, 30, 60, 90 and 110 km/h at cabin temperature of 25°C and internal heat load of 100 and 400 Watt. The results shows electric compressor has better fuel consumption and coefficient of performance compared to the conventional compressor.

  1. 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....

  2. 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....

  3. 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...

  4. SUMMARY OF ELECTRIC SERVICE COSTS FOR TOTALLY AIR CONDITIONED SCHOOLS PREPARED FOR HOUSTON INDEPENDENT SCHOOL DISTRICT, MAY 31, 1967.

    Science.gov (United States)

    WHITESIDES, M.M.

    THIS REPORT IS A COMPILATION OF DATA ON ELECTRIC AIR CONDITIONING COSTS, OPERATIONS AND MAINTENANCE. AIR CONDITIONING UNITS ARE COMPARED IN TERMS OF ELECTRIC VERSUS NON-ELECTRIC, AUTOMATIC VERSUS OPERATED, AIR COOLED VERSUS WATER COOLED, RECIPROCATING VERSUS CENTRIFUGAL COMPRESSORS, SPACE AND NOISE, REHEAT, MAINTENANCE AND ORIGINAL COST. DATA ARE…

  5. A study of air-operated valves in U.S. nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Rothberg, O. [Idaho National Engineering and Environmental Laboratory, Idaho Falls, ID (United States); Khericha, S. [Idaho National Engineering and Environmental Laboratory, Idaho Falls, ID (United States); Watkins, J. [Idaho National Engineering and Environmental Laboratory, Idaho Falls, ID (United States); Holbrook, M. [Idaho National Engineering and Environmental Laboratory, Idaho Falls, ID (United States)

    2000-02-01

    A study of air-operated valves in nuclear power plant applications was conducted for the NRC Office of Research (the project was initiated by NRC/AEOD). The results of the study were based on visits to seven nuclear power plant sites, literature studies, and examinations of event records in databases available to the NRC. The purpose is to provide information to the NRC staff concerning capabilities and performance of air-operated valves (AOVs). Descriptions of air systems and AOVs were studied along with the support systems and equipment. Systems and equipment that contain AOVs and SOVs were studied to determine their dependencies. Applications of AOVs and SOVs were listed along with current NRC requirements.

  6. 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.

  7. Early influence of bilateral turbinoplasty combined with septoplasty on intranasal air conditioning.

    Science.gov (United States)

    Lindemann, Joerg; Keck, Tilman; Leiacker, Richard; Dzida, Rene; Wiesmiller, Kerstin

    2008-01-01

    Too extensive resection of the inferior turbinates (ITs) during nasal surgery leads to a severely disturbed intranasal air conditioning. Data comparing nasal air conditioning before and after turbinoplasty in nasal surgery are still lacking. The aim of this study was to determine the early effect of bilateral turbinoplasty combined with septoplasty on intranasal heating and humidification. Twelve patients were included into this prospective study. In one-half of the patients a bilateral turbinoplasty of the IT during nasal surgery was performed, in the other half no surgery on the IT was performed. Intranasal air temperature and humidity were measured before and after surgery. A combined miniaturized thermocouple and a humidity sensor were used for simultaneous in vivo intranasal measurements. There were no statistically significant differences in temperature and humidity values between the two study groups before surgery (p > 0.05). In both groups, the postoperative temperature and humidity values were statistically significantly higher compared with the preoperative ones (p air conditioning was improved after surgery. A carefully performed and conservative reduction of the IT in nasal surgery seems to even improve intranasal air conditioning.

  8. 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.

  9. Monitoring of volatile and non-volatile urban air genotoxins using bacteria, human cells and plants.

    Science.gov (United States)

    Ceretti, E; Zani, C; Zerbini, I; Viola, G; Moretti, M; Villarini, M; Dominici, L; Monarca, S; Feretti, D

    2015-02-01

    Urban air contains many mutagenic pollutants. This research aimed to investigate the presence of mutagens in the air by short-term mutagenicity tests using bacteria, human cells and plants. Inflorescences of Tradescantia were exposed to air in situ for 6h, once a month from January to May, to monitor volatile compounds and micronuclei frequency was computed. On the same days PM10 was collected continuously for 24h. Half of each filter was extracted with organic solvents and studied by means of the Ames test, using Salmonella typhimurium TA98 and TA100 strains, and the comet assay on human leukocytes. A quarter of each filter was extracted with distilled water in which Tradescantia was exposed. PM10 concentration was particularly high in the winter season (> 50 μg/m(3)). In situ exposure of inflorescences to urban air induced a significant increase in micronuclei frequency at all the sites considered, but only in January (p urban air were able to induce genetic mutations in S. typhimurium TA98 strain (± S9), but not in TA100 strain, with a revertants/plate number nine times higher than the negative control. Comet assay showed that winter extracts were more toxic and genotoxic than spring extracts. All the mutagenicity tests performed confirmed that urban air in North Italy in winter contains both volatile and non-volatile genotoxic substances able to induce genetic damage in bacteria, human cells and plants. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Air-conditioning vs. presence of pathogenic fungi in hospital operating theatre environment.

    Science.gov (United States)

    Gniadek, Agnieszka; Macura, Anna B

    2011-01-01

    Infections related to modern surgical procedures present a difficult problem for contemporary medicine. Infections acquired during surgery represent a risk factor related to therapeutical interventions. Eradication of microorganisms from hospital operating theatre environment may contribute to reduction of infections as the laminar flow air-conditioning considerably reduces the number of microorganisms in the hospital environment. The objective of the study was to evaluate the occurrence of fungi in air-conditioned operating theatre rooms. The study was carried out in one of the hospitals in Krak6w during December 2009. Indoor air samples and imprints from the walls were collected from five operating theatre rooms. A total of fifty indoor air samples were collected with a MAS-100 device, and twenty five imprints from the walls were collected using a Count Tact method. Fungal growth was observed in 48 air samples; the average numbers of fungi were within the range of 5-100 c.f.u. in one cubic metre of the air. Fungi were detected only in four samples of the wall imprints; the number of fungi was 0.01 c.f.u. per one square centimetre of the surface. The mould genus Aspergillus was most frequently isolated, and the species A. fumigatus and A. versicolor were the dominating ones. To ensure microbiological cleanness of hospital operating theatre, the air-conditioning system should be properly maintained. Domination of the Aspergillus fungi in indoor air as well as increase in the number of moulds in the samples taken in evenings (p < 0.05) may suggest that the room decontamination procedures were neglected.

  11. Research on Using the Naturally Cold Air and the Snow for Data Center Air-conditioning, and Humidity Control

    Science.gov (United States)

    Tsuda, Kunikazu; Tano, Shunichi; Ichino, Junko

    To lower power consumption has becomes a worldwide concern. It is also becoming a bigger area in Computer Systems, such as reflected by the growing use of software-as-a-service and cloud computing whose market has increased since 2000, at the same time, the number of data centers that accumulates and manages the computer has increased rapidly. Power consumption at data centers is accounts for a big share of the entire IT power usage, and is still rapidly increasing. This research focuses on the air-conditioning that occupies accounts for the biggest portion of electric power consumption by data centers, and proposes to develop a technique to lower the power consumption by applying the natural cool air and the snow for control temperature and humidity. We verify those effectiveness of this approach by the experiment. Furthermore, we also examine the extent to which energy reduction is possible when a data center is located in Hokkaido.

  12. CFD Analysis of Manipulator Cabin by Selecting Proper Air Conditioning System

    Directory of Open Access Journals (Sweden)

    Umesh S. Ghorpade

    2017-01-01

    Full Text Available Manipulator is a machine which is used to transfer heavy objects, to reduce human efforts in many industrial applications. Some of them are fully automated while some are manually operated. It is difficult to work in cabin of manipulator for the operator under hot conditions. So it is essential to provide comfort to operator using air-conditioning system. For such applications standard air conditioners are not compatible, so we have to develop assembled system. In this paper we will be dealing with design, selection and fabrication of components like compressor, condenser, expansion device and evaporator. In order to do so, we have calculated heat load.

  13. Influence of the turbinate volumes as measured by magnetic resonance imaging on nasal air conditioning.

    Science.gov (United States)

    Lindemann, Joerg; Tsakiropoulou, Evangelia; Vital, Victor; Keck, Tilman; Leiacker, Richard; Pauls, Sandra; Wacke, Florian; Wiesmiller, Kerstin M

    2009-01-01

    Changes in nasal airflow caused by varying intranasal volumes and cross-sectional areas affect the contact between air and surrounding mucosa entailing alterations in nasal air conditioning. This study evaluates the correlation between nasal air conditioning and the volumes of the inferior and middle turbinates as measured by magnetic resonance imaging (MRI). Fourteen healthy volunteers were enrolled. Each volunteer had been examined by rhinomanometry, acoustic rhinometry, intranasal air temperature, and humidity measurements at defined intranasal sites as well as MRI of the nasal cavity and the paranasal sinuses. The volumetric data of the turbinates was based on the volumetric software Amira. Comparable results were obtained regarding absolute humidity values and temperature values within the nasal valve area and middle turbinate area for both the right and the left side of the nasal cavity. No statistically significant differences were found in the rhinomanometric values and the acoustic rhinometry results of both sides (p > 0.05). No statistical correlations were found between the volumes of the inferior (mean, 6.1 cm3) and middle turbinate (mean, 1.8 cm3) and the corresponding humidity and temperature values. Additionally, the air temperature and humidity values did not correlate with the rhinometrical endonasal volumes (0-20 mm and 20-50 mm from the nasal entrance). The normal range of volumes of the inferior and middle turbinate does not seem to have a significant impact on intranasal air conditioning in healthy subjects. The exact limits where alterations of the turbinate volume negatively affect nasal air conditioning are still unknown.

  14. Study of Air Ingress Across the Duct During the Accident Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, Yassin [Texas A & M Univ., College Station, TX (United States)

    2013-05-06

    The goal of this project is to study the fundamental physical phenomena associated with air ingress in very high temperature reactors (VHTRs). Air ingress may occur due to a rupture of primary piping and a subsequent breach in the primary pressure boundary in helium-cooled and graphite-moderated VHTRs. Significant air ingress is a concern because it introduces potential to expose the fuel, graphite support rods, and core to a risk of severe graphite oxidation. Two of the most probable air ingress scenarios involve rupture of a control rod or fuel access standpipe, and rupture in the main coolant pipe on the lower part of the reactor pressure vessel. Therefore, establishing a fundamental understanding of air ingress phenomena is critical in order to rationally evaluate safety of existing VHTRs and develop new designs that minimize these risks. But despite this importance, progress toward development these predictive capabilities has been slowed by the complex nature of the underlying phenomena. The combination of inter-diffusion among multiple species, molecular diffusion, natural convection, and complex geometries, as well as the multiple chemical reactions involved, impose significant roadblocks to both modeling and experiment design. The project team will employ a coordinated experimental and computational effort that will help gain a deeper understanding of multiphased air ingress phenomena. This project will enhance advanced modeling and simulation methods, enabling calculation of nuclear power plant transients and accident scenarios with a high degree of confidence. The following are the project tasks: Perform particle image velocimetry measurement of multiphase air ingresses; and, Perform computational fluid dynamics analysis of air ingress phenomena.

  15. Conditioning the middle ear reflex at sensation levels below reflex threshold: air jet and electrical stimulation.

    Science.gov (United States)

    McDaniel-Bacon, L; Fulton, R T; Laskowski, R P

    1980-01-01

    An ABAB functional analysis, conditioning and generalization, design was used in 3 experiments (2 were formal studies and 1 was empirical in nature) to investigate the conditionability of the middle ear reflex. The conditioned stimuli were subreflex threshold pure tones of various frequencies and intensities. The unconditioned stimulus (UCS) was an auricular air jet to the contralateral ear in the first experiment and cutaneous electrical stimulation to the ipsolateral, probe ear in the last 2 experiments. Reflexes were monitored by an otoadmittance meter, storage oscilloscope, and strip chart recorder. In the first experiment (air jet UCS), no subjects met the conditioning criterion within the maximum presentation of 400 paired trials, despite pilot evidence which indicated conditioning was feasible. In the second experiment (electrical stimulation UCS), 2 subjects met conditioning criterion; however, only one subject reconditioned and demonstrated partial generalization to other conditioned stimuli. In the third experiment (electrical stimulation UCS), one of 3 subjects who had previously been unconditionable with the air jet UCS met conditioning and reconditioning criterion and demonstrated partial generalization. Results indicate that the middle ear reflex can be conditioned to be elicited by subreflex threshold pure tones, however, results are limited.

  16. Keeping cool: use of air conditioning by australians with multiple sclerosis.

    Science.gov (United States)

    Summers, Michael P; Simmons, Rex D; Verikios, George

    2012-01-01

    Despite the known difficulties many people with MS have with high ambient temperatures, there are no reported studies of air conditioning use and MS. This study systematically examined air conditioner use by Australians with MS. A short survey was sent to all participants in the Australian MS Longitudinal Study cohort with a response rate of 76% (n = 2,385). Questions included hours of air-conditioner use, areas cooled, type and age of equipment, and the personal effects of overheating. Air conditioners were used by 81.9% of respondents, with an additional 9.6% who could not afford an air conditioner. Regional and seasonal variation in air conditioning use was reported, with a national annual mean of 1,557 hours running time. 90.7% reported negative effects from overheating including increased fatigue, an increase in other MS symptoms, reduced household and social activities, and reduced work capacity. Households that include people with MS spend between 4 and 12 times more on keeping cool than average Australian households.

  17. Preliminary verification of instantaneous air temperature estimation for clear sky conditions based on SEBAL

    Science.gov (United States)

    Zhu, Shanyou; Zhou, Chuxuan; Zhang, Guixin; Zhang, Hailong; Hua, Junwei

    2017-02-01

    Spatially distributed near surface air temperature at the height of 2 m is an important input parameter for the land surface models. It is of great significance in both theoretical research and practical applications to retrieve instantaneous air temperature data from remote sensing observations. An approach based on Surface Energy Balance Algorithm for Land (SEBAL) to retrieve air temperature under clear sky conditions is presented. Taking the meteorological measurement data at one station as the reference and remotely sensed data as the model input, the research estimates the air temperature by using an iterative computation. The method was applied to the area of Jiangsu province for nine scenes by using MODIS data products, as well as part of Fujian province, China based on four scenes of Landsat 8 imagery. Comparing the air temperature estimated from the proposed method with that of the meteorological station measurement, results show that the root mean square error is 1.7 and 2.6 °C at 1000 and 30 m spatial resolution respectively. Sensitivity analysis of influencing factors reveals that land surface temperature is the most sensitive to the estimation precision. Research results indicate that the method has great potentiality to be used to estimate instantaneous air temperature distribution under clear sky conditions.

  18. Catalytic wet-air oxidation of a chemical plant wastewater over platinum-based catalysts.

    Science.gov (United States)

    Cybulski, Andrzej; Trawczyński, Janusz

    2006-01-01

    Catalytic wet-air oxidation (CWAO) of wastewater (chemical oxygen demand [COD] = 1800 mg O2/dm3) from a fine chemicals plant was investigated in a fixed-bed reactor at T = 393-473 K under total pressure of 5.0 or 8.0 MPa. Catalysts containing 0.3% wt. of platinum deposited on two supports, mixed silica-titania (SM1) and carbon black composites (CBC) were used. The CBC-supported catalyst appeared to be more active than the SM1-supported one. A slow decrease of activity of the platinum on SM1 (Pt-SM1) during the long-term operation is attributed to recrystallization of titania and leaching of a support component, while the Pt-CBC catalyst is deteriorated, owing to combustion of the support component. The power-law-kinetic equations were used to describe the rate of COD removal at CWAO over the catalysts. The kinetic parameters of COD reduction for the wastewater were determined and compared with the kinetic parameters describing phenol oxidation over the same catalysts. Rates of COD removal for the wastewater were found higher than those for phenol oxidation over the same catalysts and under identical operating conditions.

  19. Dispersal potential in plant communities depends on environmental conditions

    NARCIS (Netherlands)

    Ozinga, W.A.; Bekker, R.M.; Schaminée, J.H.J.; Groenendael, van J.M.

    2004-01-01

    Local plant communities can only function within a metacommunity context if they are connected by appropriate dispersal vectors, accommodating the transport of propagules between sites. The capacity for long-distance dispersal may be a key factor in the survival of local populations, especially in f

  20. Dispersal potential in plant communities depends on environmental conditions

    NARCIS (Netherlands)

    Ozinga, W.A.; Bekker, R.M.; Schaminée, J.H.J.; Groenendael, J.M. van

    2004-01-01

    1 Local plant communities can only function within a metacommunity context if they are connected by appropriate dispersal vectors, accommodating the transport of propagules between sites. The capacity for long-distance dispersal may be a key factor in the survival of local populations, especially in