WorldWideScience

Sample records for air heaters

  1. Solar air heaters and their applications

    Science.gov (United States)

    Selcuk, M. K.

    1977-01-01

    The solar air heater appears to be the most logical choice, as far as the ultimate application of heating air to maintain a comfortable environment is concerned. One disadvantage of solar air heaters is the need for handling larger volumes of air than liquids due to the low density of air as a working substance. Another disadvantage is the low thermal capacity of air. In cases where thermal storage is needed, water is superior to air. Design variations of solar air heaters are discussed along with the calculation of the efficiency of a flat plate solar air heater, the performance of various collector types, and the applications of solar air heaters. Attention is given to collectors with nonporous absorber plates, collectors with porous absorbers, the performance of flat plate collectors with finned absorbers, a wire mesh absorber, and an overlapped glass plate air heater.

  2. Solar Air Heaters with Thermal Heat Storages

    Directory of Open Access Journals (Sweden)

    Abhishek Saxena

    2013-01-01

    Full Text Available Solar energy can be converted into different forms of energy, either to thermal energy or to electrical energy. Solar energy is converted directly into electrical power by photovoltaic modules, while solar collector converts solar energy into thermal energy. Solar collector works by absorbing the direct solar radiation and converting it into thermal energy, which can be stored in the form of sensible heat or latent heat or a combination of sensible and latent heats. A theoretical study has been carried out to rate the various thermal energy storage commonly used in solar air heaters. During the investigations rock bed storages have been found to be low type thermal heat storage, while phase change materials have been found to be high heat thermal storages. Besides this, a few other heat storing materials have been studied and discussed for lower to higher ratings in terms of thermal performance purposely for solar heaters.

  3. Impact of kerosene space heaters on indoor air quality.

    Science.gov (United States)

    Hanoune, B; Carteret, M

    2015-09-01

    In recent years, the use of kerosene space heaters as additional or principal heat source has been increasing, because these heaters allow a continuous control on the energy cost. These devices are unvented, and all combustion products are released into the room where the heaters are operated. The indoor air quality of seven private homes using wick-type or electronic injection-type kerosene space heaters was investigated. Concentrations of CO, CO2, NOx, formaldehyde and particulate matter (0.02-10 μm) were measured, using time-resolved instruments when available. All heaters tested are significant sources of submicron particles, NOx and CO2. The average NO2 and CO2 concentrations are determined by the duration of use of the kerosene heaters. These results stress the need to regulate the use of unvented combustion appliances to decrease the exposure of people to air contaminants.

  4. Flat plate solar air heater with latent heat storage

    Science.gov (United States)

    Touati, B.; Kerroumi, N.; Virgone, J.

    2017-02-01

    Our work contains two parts, first is an experimental study of the solar air heater with a simple flow and forced convection, we can use thatlaste oneit in many engineering's sectors as solardrying, space heating in particular. The second part is a numerical study with ansys fluent 15 of the storage of part of this solar thermal energy produced,using latent heat by using phase change materials (PCM). In the experimental parts, we realize and tested our solar air heater in URER.MS ADRAR, locate in southwest Algeria. Where we measured the solarradiation, ambient temperature, air flow, thetemperature of the absorber, glasses and the outlet temperature of the solar air heater from the Sunrise to the sunset. In the second part, we added a PCM at outlet part of the solar air heater. This PCM store a part of the energy produced in the day to be used in peak period at evening by using the latent heat where the PCMs present a grateful storagesystem.A numerical study of the fusion or also named the charging of the PCM using ANSYS Fluent 15, this code use the method of enthalpies to solve the fusion and solidification formulations. Furthermore, to improve the conjugate heat transfer between the heat transfer fluid (Air heated in solar plate air heater) and the PCM, we simulate the effect of adding fins to our geometry. Also, four user define are write in C code to describe the thermophysicalpropriety of the PCM, and the inlet temperature of our geometry which is the temperature at the outflow of the solar heater.

  5. Comparative performance of coriander dryer coupled to solar air heater and solar air-heater-cum-rockbed storage

    Energy Technology Data Exchange (ETDEWEB)

    Chauhan, P.M.; Choudhury, C.; Garg, H.P. [Indian Inst. of Technology, Centre for Energy Studies, New Delhi (India)

    1996-03-01

    In the present communication, efforts have been made to study the drying characteristics of coriander in a stationary 0.5 tonne/batch capacity deep-bed dryer coupled to a solar air heater and a rockbed storage unit to receive hot air during sunshine and off-sunshine hours, respectively. The drying bed was assumed to consist of a number of thin layers of grains stacked upon each other. The theoretical investigation was made by writing the energy and mass balance equations for different components of the dryer-cum-air-heater-cum-storage and by adopting a finite difference approach for simulation. (author)

  6. 30 CFR 75.341 - Direct-fired intake air heaters.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Direct-fired intake air heaters. 75.341 Section... air heaters. (a) If any system used to heat intake air malfunctions, the heaters affected shall switch off automatically. (b) Thermal overload devices shall protect the blower motor from overheating....

  7. An experimental evaluation of multi-pass solar air heaters

    Energy Technology Data Exchange (ETDEWEB)

    Satcunanathan, S.; Persad, P.

    1980-12-01

    Three collectors of identical dimensions but operating in the single-pass, two-pass and three-pass modes were tested simultaneously under ambient conditions. It was found that the two-pass air heater was consistently better than the single-pass air heater over the day for the range of mass flow rates considered. It was also found that at a mass flow rate of 0.0095 kg s/sup -1/ m/sup -2/, the thermal performances of the two-pass and three-pass collectors were identical, but at higher flow rates the two-pass collector was superior to the three-pass collector, the superiority decreasing with increasing mass flow rate.

  8. Exergetic performance evaluation and parametric studies of solar air heater

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, M.K.; Kaushik, S.C. [Centre for Energy Studies, Indian Institute of Technology, Delhi 110016 (India)

    2008-11-15

    The present study aims to establish the optimal performance parameters for the maximum exergy delivery during the collection of solar energy in a flat-plate solar air heater. The procedure to determine optimum aspect ratio (length to width ratio of the absorber plate) and optimum duct depth (the distance between the absorber and the bottom plates) for maximum exergy delivery has been developed. It is known that heat energy gain and blower work increase monotonically with mass flow rate, while the temperature of air decreases; therefore, it is desirable to incorporate the quality of heat energy collected and the blower work. First it is proved analytically that the optimum exergy output, neglecting blower work, and the corresponding mass flow rate depend on the inlet temperature of air. The energy and exergy output rates of the solar air heater were evaluated for various values of collector aspect ratio (AR) of the collector, mass flow rate per unit area of the collector plate (G) and solar air heater duct depth (H). Results have been presented to discuss the effects of G, AR and H on the energy and exergy output rates of the solar air heater. The energy output rate increases with G and AR, and decreases with H and the inlet temperature of air. The exergy-based evaluation criterion shows that performance is not a monotonically increasing function of G and AR, and a decreasing function of H and inlet temperature of air. Based on the exergy output rate, it is found that there must be an optimum inlet temperature of air and a corresponding optimum G for any value of AR and H. For values of G lesser than optimal corresponding to inlet temperature of air equals to ambient, higher exergy output rate is achieved for the low value of duct depth and high AR in the range of parameters investigated. If G is high, for an application requiring less temperature increase, then either low AR or high H would give higher exergy output rate. (author)

  9. Thermal performance optimization of a flat plate solar air heater using genetic algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Varun; Siddhartha [Department of Mechanical Engineering, National Institute of Technology, Hamirpur 177 005 (H.P.) (India)

    2010-05-15

    Thermal performance of solar air heater is low and different techniques are adopted to increase the performance of solar air heaters, such as: fins, artificial roughness etc. In this paper an attempt has been done to optimize the thermal performance of flat plate solar air heater by considering the different system and operating parameters to obtain maximum thermal performance. Thermal performance is obtained for different Reynolds number, emissivity of the plate, tilt angle and number of glass plates by using genetic algorithm. (author)

  10. Analysis of exergy and parametric study of a v-corrugated solar air heater

    Energy Technology Data Exchange (ETDEWEB)

    Hedayatizadeh, Mahdi [University of Tabriz, Department of Agricultural Machinery Engineering, Faculty of Agriculture, Tabriz (Iran, Islamic Republic of); University of Birjand, Faculty of Agriculture, P.O. Box 97175/331, Birjand (Iran, Islamic Republic of); Ajabshirchi, Yahya [University of Tabriz, Department of Agricultural Machinery Engineering, Faculty of Agriculture, Tabriz (Iran, Islamic Republic of); Sarhaddi, Faramarz; Farahat, Said [University of Sistan and Baluchestan, Department of Mechanical Engineering, Faculty of Engineering, P.O. Box 98164/161, Zahedan (Iran, Islamic Republic of); Safavinejad, Ali [University of Birjand, Department of Mechanical Engineering, Faculty of Engineering, Birjand (Iran, Islamic Republic of); Chaji, Hossein [University of Tabriz, Department of Agricultural Machinery Engineering, Faculty of Agriculture, Tabriz (Iran, Islamic Republic of); Center of Agriculture and Natural Resources of Khorasan Razavi Province, Ministry of Agriculture, Mashhad (Iran, Islamic Republic of)

    2012-07-15

    Solar air heater requires investigation for enhancement of solar energy conversion into heat. Different configurations with various artificial roughness geometries are proposed to date. In present study attention is paid on ways leading to more delivery of exergy by a v-corrugated solar air heater through parametric study. Effects of aspect ratio of the collector, inlet air temperature, mass flow rate per collector area etc. are studied. (orig.)

  11. Experimental investigation of three different solar air heaters: Energy and exergy analyses

    Energy Technology Data Exchange (ETDEWEB)

    Alta, Deniz; Ertekin, C.; Yaldiz, Osman [Department of Farm Machinery, Faculty of Agricultural Engineering, Akdeniz University, 07059 Antalya (Turkey); Bilgili, Emin [Cukurova Agricultural Research Institute, Adana (Turkey)

    2010-10-15

    The present study aims to compare three different types of designed flat-plate solar air heaters, two having fins (Type II and Type III) and the other without fins (Type I), one of the heater with a fin had single glass cover (Type III) and the others had double glass covers (Type I and Type II). The energy and exergy output rates of the solar air heaters were evaluated for various air flow rates (25, 50 and 100 m{sup 3}/m{sup 2} h), tilt angle (0 , 15 and 30 ) and temperature conditions versus time. Based on the energy and exergy output rates, heater with double glass covers and fins (Type II) is more effective and the difference between the input and output air temperature is higher than of the others. Besides, it is found that the circulation time of air inside the heater played a role more important than of the number of transparent sheet. Lower air flow rates should be preferred in the applications of which temperature differences is more important. (author)

  12. Effective efficiency prediction for discrete type of ribs used in solar air heaters

    Directory of Open Access Journals (Sweden)

    Muneesh Sethi, Mridul Sharma, Varun

    2010-03-01

    Full Text Available The use of an artificial roughness on a surface is an effective technique to enhance the heat transfer from the collector plate to the air in a solar air heater duct. However, artificial roughness leads to even more fluid pressure thereby increasing the pumping power. Number of geometries of roughness elements has been investigated on the heat transfer and friction characteristics of solar air heater ducts. This paper presents a comparison of effective efficiency of solar air heaters having different types of geometry of roughness elements (discrete ribs on the absorber plate. The effective efficiency has been computed by using the correlations for heat transfer and friction factor developed by various investigators within the investigated range of operating and system parameters.

  13. Assessment of Performance Characteristic of Solar Air Heater with Assorted Geometries - A Review

    Directory of Open Access Journals (Sweden)

    Alok Kumar Rohit

    2016-01-01

    Full Text Available Artificial roughness is an efficient way for increasing the heat transfer rate in solar air heater with the corresponding improvement in its thermal performance. A viscous sub-layer is responsible for the low heat transfer coefficient between absorber plate and flowing air. Repeated ribs in form of artificial roughness are an effective way to increase the heat transfer rate and improving the performance of solar air heater. Artificial roughness of the absorber plate is much economical and effective way to improve the thermal performance of solar air heater. Several investigators have done various investigations to improve heat transfer coefficient with little penalty of friction factor. They have also developed different correlation for heat transfer coefficient and friction factor. The correlations developed for heat transfer and friction factor by various investigators have been reviewed and presented.

  14. Novel solar air Heater for high temperatures; Novedoso Calentador solar de aire para altas temperaturas

    Energy Technology Data Exchange (ETDEWEB)

    Rincon, E. A.; Duran, M. D.; Lentz, A. E.

    2008-07-01

    A novel solar air heater that allows to reach temperatures of the order of 100 degree centigrade with thermal efficiencies superior to 50% due to a solar concentrator and the reduction of thermal losses from the air when circulating between the absorber and mirrors of section of circular arc, well isolated of the outside surrounding. The receiver consists of a concentrator with wedges of plastic transparency that make the function of lenses. The light refracted by the wedges enters to a series of concentrators PC type truncated optimally so that the space among them allows the positioning of the absorber, who are covered metallic segments with selective film. Its excellent performance makes ideals applications as Sauna bath, the drying at high temperature, and systems for conditioning of air. (Author)

  15. Performance estimation of artificially roughened solar air heater duct provided with continuous ribs

    Directory of Open Access Journals (Sweden)

    Mridul Sharma, Varun

    2010-09-01

    Full Text Available The use of an artificial roughness on a surface is an effective technique to enhance the rate of heat transfer to fluid flow in the duct of a solar air heater. This paper presents a comparison of exergetic performance of solar air heaters having different types of geometry of roughness elements (continuous ribs on the absorber plate. The exergy efficiency has been computed by using the correlations for heat transfer and friction factor developed by various investigators within the investigated range of operating and system parameters. The exergy efficiency based criterion shows the better results at lower value of Re. There is not a single roughness geometry which gives best exergetic performance for whole range of Reynolds number. Solar air heater having rib-grooved and arc shaped wire as artificial roughness is found to have better exergy efficiency in the lower range of Reynolds number. However, smooth duct is found suitable in the higher range of Reynolds number.

  16. The benefit of solid oxide fuel cells with integrated air pre-heater

    Energy Technology Data Exchange (ETDEWEB)

    Costamagna, P. [Univ. degli Studi di Genova, Fac. di Ingegneria, ISTIC, Inst. di Ingegneria Chimica e di Processo `G.B. Bonino`, Genova (Italy)

    1997-11-01

    A new design has recently been proposed in the field of solid oxide fuel cells, consisting of a traditional electrochemical cell integrated with a pre-heater. In this paper a simulation model for the rectangular planar solid oxide fuel cell with integrated air pre-heater is presented. A two-dimensional stack simulation is presented as well, one axis coincides with the fuel flow direction, the other with the stack height. Local quantities such as current density, gas and solid temperatures are reported and cell characteristics predicted. In a parameter study, effects of oxygen utilisation and heat-transfer conditions in the pre-heater on the local temperature distribution of the solid structure are considered. As a result, the benefit of the new cell design becomes evident when low air flow rates are applied. A further advantage associated with the reduced flow rate is the low air temperature at the inlet. (orig.)

  17. Energy and exergy analysis in double-pass solar air heater

    Indian Academy of Sciences (India)

    P VELMURUGAN; R KALAIVANAN

    2016-03-01

    In this study, an attempt is made to improve the energy and exergy performance of solar air heater by employing double pass with different absorber surface geometries (roughened, finned, and v-corrugated wire mesh) in the second pass, and also by mounting longitudinal fins in the back side of the absorber plate (first pass). The effect of varied mass flow rate and solar intensity on temperature rise of air, energy efficiency, exergy gain and pressure drop at steady state condition was determined for different types of solar air heaters utilizing an indoor solar simulator. The temperature rise of air, thermal efficiency and exergy gain depends on mass flow rate, surface geometries of absorber and solar intensity, whereas the pressure drop depends on mass flow rate andsurface geometries of absorber.

  18. Modeling of a split type air conditioner with integrated water heater

    Energy Technology Data Exchange (ETDEWEB)

    Techarungpaisan, P.; Theerakulpisut, S.; Priprem, S. [Mechanical Engineering Department, Faculty of Engineering, Khon Kaen University, 123 Mittrapab Rd., Muang, Khon Kaen 40002 (Thailand)

    2007-04-15

    This paper presents a steady state simulation model to predict the performance of a small split type air conditioner with integrated water heater. The mathematical model consists of submodels of system components such as evaporator, condenser, compressor, capillary tube, receiver and water heater. These submodels were built based on fundamental principles of heat transfer, thermodynamics, fluid mechanics, empirical relationships and manufacturer's data as necessary. The model was coded into a simulation program and used to predict system parameters of interest such as hot water temperature, condenser exit air temperature, evaporator exit air temperature, mass flow rate of refrigerant, heat rejection in the condenser and cooling capacity of the system. The simulation results were compared with experimental data obtained from an experimental rig built for validating the mathematical model. It was found that the experimental and simulation results are in good agreement. (author)

  19. Performance study of solar air heater duct having absorber plate with V down perforated baffles

    Directory of Open Access Journals (Sweden)

    Sunil Chamoli

    2014-04-01

    Full Text Available This paper presents results of a study of the performance of solar air heaters with V down perforated baffles as roughness on the air flow side of the absorber plate. Investigations have been carried out using a mathematical model to study the effects of ambient conditions, operating and design parameters on effective efficiency of such air heaters. The thermal and effective efficiencies differ only marginally at lower flow rates. With an increase in the flow rate, the difference between the thermal and effective efficiencies increases because of the increase in the pumping power. The results of the study are presented in the form of plots to show the effect of ambient, design and operating conditions on thermal and effective efficiency.

  20. Large eddy simulation of combustion instability in a tripropellant air heater

    Science.gov (United States)

    Yuan, Lei; Shen, Chibing

    2016-12-01

    This research is motivated by the issue associated with high frequency combustion instability. Large eddy simulation was performed to investigate spontaneous combustion instability in an air/LO2/C2H5OH tripropellant air heater. The simulation predicts self-excited transverse oscillations. Overall behavior of combustion instability including pressure time histories, mode shapes, Rayleigh index and unsteady response of the injector were studied in detail. Special emphasis was given to the flame behavior, droplet trajectories, pressure evolutions, and formation of large-scale vortical structures during combustion instability in present air heater. Furthermore, in contrast to previous investigations, a new process is identified in the simulation that may feed energy into the acoustic mode and drive combustion instability.

  1. Materials performance in the atmospheric fluidized-bed cogeneration air heater experiment

    Energy Technology Data Exchange (ETDEWEB)

    Natesan, K.; Podolski, W.; Wang, D.Y.; Teats, F.G. (Argonne National Lab., IL (United States)); Gerritsen, W.; Stewart, A.; Robinson, K. (Rockwell International Corp., Canoga Park, CA (United States))

    1991-02-01

    The Atmospheric Fluidized-Bed Cogeneration Air Heater Experiment (ACAHE) sponsored by the US Department of Energy (DOE) was initiated to assess the performance of various heat-exchanger materials to be used in fluidized-bed combustion air heater systems. Westinghouse Electric Corporation, through subcontracts with Babcock Wilcox, Foster Wheeler, and ABB Combustion Engineering Systems, prepared specifications and hardware for the ACAHE tests. Argonne National Laboratory contracted with Rockwell International to conduct tests in the DOE atmospheric fluidized-bed combustion facility. This report presents an overview of the project, a description of the facility and the test hardware, the test operating conditions, a summary of the operation, and the results of analyzing specimens from several uncooled and cooled probes exposed in the facility. Extensive microstructural analyses of the base alloys, claddings, coatings, and weldments were performed on specimens exposed in several probes for different lengths of time. Alloy penetration data were determined for several of the materials as a function of specimen orientation and the exposure location in the combustor. Finally, the data were compared with earlier laboratory test data, and the long-term performance of candidate materials for air-heater applications was assessed.

  2. Thermography and Sonic Anemometry to Analyze Air Heaters in Mediterranean Greenhouses

    Directory of Open Access Journals (Sweden)

    Araceli Peña

    2012-10-01

    Full Text Available The present work has developed a methodology based on thermography and sonic anemometry for studying the microclimate in Mediterranean greenhouses equipped with air heaters and polyethylene distribution ducts to distribute the warm air. Sonic anemometry allows us to identify the airflow pattern generated by the heaters and to analyze the temperature distribution inside the greenhouse, while thermography provides accurate crop temperature data. Air distribution by means of perforated polyethylene ducts at ground level, widely used in Mediterranean-type greenhouses, can generate heterogeneous temperature distributions inside the greenhouse when the system is not correctly designed. The system analyzed in this work used a polyethylene duct with a row of hot air outlet holes (all of equal diameter that expel warm air toward the ground to avoid plant damage. We have observed that this design (the most widely used in Almería’s greenhouses produces stagnation of hot air in the highest part of the structure, reducing the heating of the crop zone. Using 88 kW heating power (146.7 W∙m−2 the temperature inside the greenhouse is maintained 7.2 to 11.2 °C above the outside temperature. The crop temperature (17.6 to 19.9 °C was maintained above the minimum recommended value of 10 °C.

  3. Thermography and Sonic Anemometry to Analyze Air Heaters in Mediterranean Greenhouses

    Science.gov (United States)

    López, Alejandro; Valera, Diego L.; Molina-Aiz, Francisco; Peña, Araceli

    2012-01-01

    The present work has developed a methodology based on thermography and sonic anemometry for studying the microclimate in Mediterranean greenhouses equipped with air heaters and polyethylene distribution ducts to distribute the warm air. Sonic anemometry allows us to identify the airflow pattern generated by the heaters and to analyze the temperature distribution inside the greenhouse, while thermography provides accurate crop temperature data. Air distribution by means of perforated polyethylene ducts at ground level, widely used in Mediterranean-type greenhouses, can generate heterogeneous temperature distributions inside the greenhouse when the system is not correctly designed. The system analyzed in this work used a polyethylene duct with a row of hot air outlet holes (all of equal diameter) that expel warm air toward the ground to avoid plant damage. We have observed that this design (the most widely used in Almería's greenhouses) produces stagnation of hot air in the highest part of the structure, reducing the heating of the crop zone. Using 88 kW heating power (146.7 W·m−2) the temperature inside the greenhouse is maintained 7.2 to 11.2 °C above the outside temperature. The crop temperature (17.6 to 19.9 °C) was maintained above the minimum recommended value of 10 °C. PMID:23202025

  4. Thermography and sonic anemometry to analyze air heaters in Mediterranean greenhouses.

    Science.gov (United States)

    López, Alejandro; Valera, Diego L; Molina-Aiz, Francisco; Peña, Araceli

    2012-10-16

    The present work has developed a methodology based on thermography and sonic anemometry for studying the microclimate in Mediterranean greenhouses equipped with air heaters and polyethylene distribution ducts to distribute the warm air. Sonic anemometry allows us to identify the airflow pattern generated by the heaters and to analyze the temperature distribution inside the greenhouse, while thermography provides accurate crop temperature data. Air distribution by means of perforated polyethylene ducts at ground level, widely used in Mediterranean-type greenhouses, can generate heterogeneous temperature distributions inside the greenhouse when the system is not correctly designed. The system analyzed in this work used a polyethylene duct with a row of hot air outlet holes (all of equal diameter) that expel warm air toward the ground to avoid plant damage. We have observed that this design (the most widely used in Almería's greenhouses) produces stagnation of hot air in the highest part of the structure, reducing the heating of the crop zone. Using 88 kW heating power (146.7 W ∙ m(-2)) the temperature inside the greenhouse is maintained 7.2 to 11.2 °C above the outside temperature. The crop temperature (17.6 to 19.9 °C) was maintained above the minimum recommended value of 10 °C.

  5. MHD air heater technology development. Annual technical progress report, January 1, 1980-December 31, 1980

    Energy Technology Data Exchange (ETDEWEB)

    None

    1981-03-01

    Progress on the technology development of the directly-fired high temperature air heater (HTAH) for MHD power plants is described in detail. The objective of task 1 is to continue development of ceramic materials technology for the directly-fired HTAH. The objectives of task 2 are to demonstrate the technical feasibility of operating a directly-fired HTAH (including both the heater matrix and valves), to continue obtaining information on life and corrosion resistance of HTAH materials, and to obtain design information for full-scale studies and future design work. The objectives of task 3 are to begin the identification of HTAH control requirements and control system needs, and to continue full-scale study efforts incorporating updated materials and design information in order to identify development needs for the HTAH development program. (WHK)

  6. Performance evaluation of solar air heaters having v-down discrete rib roughness on the absorber plate

    Energy Technology Data Exchange (ETDEWEB)

    Karwa, Rajendra; Chauhan, Kalpana [Department of Mechanical Engineering, Faculty of Engineering and Architecture, Jai Narain Vyas University, Jodhpur 342 011 (India)

    2010-01-15

    This paper presents results of a study of the performance of solar air heaters with 60 v-down discrete rectangular cross-section repeated rib roughness on the air flow side of the absorber plate. A detailed investigation has been carried out using a mathematical model to study the effects of various ambient, operating and design parameters on the thermal efficiency and effective efficiency (based on the net gain after taking account of the pumping power) of such air heaters. The study shows that, at air mass flow rates less than about 0.04 kg s{sup -1} per m{sup 2} of the absorber plate, roughened duct solar air heaters provide significant performance advantage over the smooth duct air heater. The thermal and effective efficiencies differ only marginally at low flow rates. With the increase in the flow rate, the difference between the thermal and effective efficiencies increases because of the increase in the pumping power. At the mass flow rate of about 0.045 kg s{sup -1} m{sup -2}, the effective efficiencies of the roughened and smooth duct solar air heaters are practically the same. The results of the study are presented in the form of design plots. (author)

  7. Experimental study of heat transfer and thermal performance with longitudinal fins of solar air heater

    Science.gov (United States)

    Chabane, Foued; Moummi, Noureddine; Benramache, Said

    2013-01-01

    The thermal performance of a single pass solar air heater with five fins attached was investigated experimentally. Longitudinal fins were used inferior the absorber plate to increase the heat exchange and render the flow fluid in the channel uniform. The effect of mass flow rate of air on the outlet temperature, the heat transfer in the thickness of the solar collector, and the thermal efficiency were studied. Experiments were performed for two air mass flow rates of 0.012 and 0.016 kg s−1. Moreover, the maximum efficiency values obtained for the 0.012 and 0.016 kg s−1 with and without fins were 40.02%, 51.50% and 34.92%, 43.94%, respectively. A comparison of the results of the mass flow rates by solar collector with and without fins shows a substantial enhancement in the thermal efficiency. PMID:25685486

  8. Single and double pass solar air heaters with wire mesh as packing bed

    Energy Technology Data Exchange (ETDEWEB)

    Aldabbagh, L.B.Y.; Egelioglu, F. [Mechanical Engineering Department, Eastern Mediterranean University, Magosa, Mersin 10 (Turkey); Ilkan, M. [School of Computing and Tecnology, Eastern Mediterranean University, Magosa, Mersin 10 (Turkey)

    2010-09-15

    The thermal performances of single and double pass solar air heaters with steel wire mesh layers are used instead of a flat absorber plate are investigated experimentally. The effects of mass flow rate of air on the outlet temperature and thermal efficiency were studied. The results indicate that the efficiency increases with increasing the mass flow rate for the range of the flow rate used in this work between 0.012 and 0.038 kg/s. For the same flow rate, the efficiency of the double pass is found to be higher than the single pass by 34-45%. Moreover, the maximum efficiencies obtained for the single and the double pass air collectors are 45.93 and 83.65% respectively for the mass flow rate of 0.038 kg/s. Comparison of the results of a packed bed collector with those of a conventional collector shows a substantial enhancement in the thermal efficiency. (author)

  9. Experimental study of heat transfer and thermal performance with longitudinal fins of solar air heater

    Directory of Open Access Journals (Sweden)

    Foued Chabane

    2014-03-01

    Full Text Available The thermal performance of a single pass solar air heater with five fins attached was investigated experimentally. Longitudinal fins were used inferior the absorber plate to increase the heat exchange and render the flow fluid in the channel uniform. The effect of mass flow rate of air on the outlet temperature, the heat transfer in the thickness of the solar collector, and the thermal efficiency were studied. Experiments were performed for two air mass flow rates of 0.012 and 0.016 kg s−1. Moreover, the maximum efficiency values obtained for the 0.012 and 0.016 kg s−1 with and without fins were 40.02%, 51.50% and 34.92%, 43.94%, respectively. A comparison of the results of the mass flow rates by solar collector with and without fins shows a substantial enhancement in the thermal efficiency.

  10. Experimental study of heat transfer and thermal performance with longitudinal fins of solar air heater.

    Science.gov (United States)

    Chabane, Foued; Moummi, Noureddine; Benramache, Said

    2014-03-01

    The thermal performance of a single pass solar air heater with five fins attached was investigated experimentally. Longitudinal fins were used inferior the absorber plate to increase the heat exchange and render the flow fluid in the channel uniform. The effect of mass flow rate of air on the outlet temperature, the heat transfer in the thickness of the solar collector, and the thermal efficiency were studied. Experiments were performed for two air mass flow rates of 0.012 and 0.016 kg s(-1). Moreover, the maximum efficiency values obtained for the 0.012 and 0.016 kg s(-1) with and without fins were 40.02%, 51.50% and 34.92%, 43.94%, respectively. A comparison of the results of the mass flow rates by solar collector with and without fins shows a substantial enhancement in the thermal efficiency.

  11. Effects of Delta-Shaped Obstacles on the Thermal Performance of Solar Air Heater

    Directory of Open Access Journals (Sweden)

    Adisu Bekele

    2011-01-01

    Full Text Available An experimental investigation has been carried out to study the effect of delta-shaped obstacles mounted on the absorber surface of an air heater duct with an aspect ratio 6 : 1 resembling the conditions close to solar air heaters. This study encompassed the Reynolds number (Re ranging from 3400 to 27600, longitudinal pitch of the obstacle (Pl/e varied from 3/2 to 11/2, and relative obstacle height (e/H varied from 0.25 to 0.75. The relative obstacle transverse pitch (Pt/b=7/3 and the angle of attack of flow on obstacle = 90° are kept constant during the whole experimentation. By comparing the heat transfer data obtained from the obstacle-mounted duct with that of smooth duct under similar geometrical and flow conditions, the obstacle-mounted duct enhances the heat transfer by 3.6-times at Re = 7276.82, Pl/e=3/2, and e/H=0.75.

  12. Device Performance Improvement of Double-Pass Wire Mesh Packed Solar Air Heaters under Recycling Operation Conditions

    Directory of Open Access Journals (Sweden)

    Chii-Dong Ho

    2016-01-01

    Full Text Available The improvement of device performance of a recycling solar air heater featuring a wire mesh packing was investigated experimentally and theoretically. The application of the wire mesh packing and recycle-effect concept to the present study were proposed aiming to strengthen the convective heat-transfer coefficient due to increased turbulence. Comparisons were made among different designs, including the single-pass, flat-plate double-pass and recycling double-pass wire mesh packed operations. The collector efficiency of the recycling double-pass wire mesh packed solar air heater was much higher than that of the other configurations for various recycle ratios and mass flow rates scenarios. The power consumption increment due to implementing wire mesh in solar air heaters was also discussed considering the economic feasibility. A fairly good agreement between theoretical predictions and experimental measurements was achieved with an analyzed error of 1.07%–9.32%.

  13. Performance Analysis and Parametric Study of a Natural Convection Solar Air Heater With In-built Oil Storage

    Science.gov (United States)

    Dhote, Yogesh; Thombre, Shashikant

    2016-10-01

    This paper presents the thermal performance of the proposed double flow natural convection solar air heater with in-built liquid (oil) sensible heat storage. Unused engine oil was used as thermal energy storage medium due to its good heat retaining capacity even at high temperatures without evaporation. The performance evaluation was carried out for a day of the month March for the climatic conditions of Nagpur (India). A self reliant computational model was developed using computational tool as C++. The program developed was self reliant and compute the performance parameters for any day of the year and would be used for major cities in India. The effect of change in storage oil quantity and the inclination (tilt angle) on the overall efficiency of the solar air heater was studied. The performance was tested initially at different storage oil quantities as 25, 50, 75 and 100 l for a plate spacing of 0.04 m with an inclination of 36o. It has been found that the solar air heater gives the best performance at a storage oil quantity of 50 l. The performance of the proposed solar air heater is further tested for various combinations of storage oil quantity (50, 75 and 100 l) and the inclination (0o, 15o, 30o, 45o, 60o, 75o, 90o). It has been found that the proposed solar air heater with in-built oil storage shows its best performance for the combination of 50 l storage oil quantity and 60o inclination. Finally the results of the parametric study was also presented in the form of graphs carried out for a fixed storage oil quantity of 25 l, plate spacing of 0.03 m and at an inclination of 36o to study the behaviour of various heat transfer and fluid flow parameters of the solar air heater.

  14. Performances of packed bed double pass solar air heater with different inclinations and transverse wire mesh with different intervals

    Directory of Open Access Journals (Sweden)

    Sugantharaj Gnanadurai Sam Stanley

    2016-01-01

    Full Text Available Solar air heating is a technology in which the solar energy from the sun is captured by an absorbing medium and used to heat the air flowing through the heater. In this study, thermal performance of a double pass solar air heater has been investigated experimentally at different conditions. The experiments were conducted with different inclinations of the collector, with and without wire mesh vertically fixed at the second pass in transverse direction and with different mass flow rates. The effect of air mass flow rate, wire mesh pitch and collector inclination on temperature rise and thermal efficiency have been studied. Results show that efficiency increases with mass flow rate. For the same mass flow rate, the thermal efficiency increases with the decrease in the wire mesh pitch. The maximum daily average efficiency of air heater was 79.8% at 0.025 kg/s mass flow rate, 10 cm wire mesh gap and 9º collector inclination facing south. The highest collector efficiency was observed in solar air heaters with 10 cm wire mesh gap.

  15. MHD air heater development technology. Technical progress report, April 1, 1980-June 30, 1980

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-07-01

    Technology development for the directly-fired high temperature air heater (HTAH) for MHD power plants is described. Work is being done under three tasks as described in the following. (1) materials selection, evaluation, and development: The objective of this task is to continue development of ceramic materials technology for the directly-fired HTAH. The scope of the work will include compilation of materials data, materials selection for testing and design studies, materials property determination, liaison with refractory manufacturers and other organizations to encourage development of materials and fabrication technology, establishment of preliminary HTAH material specifications, analyses of test materials, and development of criteria for thermal stress limits for crack-tolerant refractory materials. (2) operability, performance, and materials testing: The objectives of this task are to demonstrate the technical feasibility of operating a directly-fired HTAH (including both the heater matrix and valves), to continue obtaining information on life and corrosion resistance of HTAH materials, and to obtain design information for full-scale studies and future design work. (3) full-scale design concepts: The objectives of this task are to begin the identification of HTAH control requirements and control system needs, and to continue full-scale study efforts incorporating updated materials and design information in order to identify development needs for the HTAH development program. Progress is described. (WHK)

  16. Sensitivity analysis of thermal performances of flat plate solar air heaters

    Science.gov (United States)

    Njomo, Donatien; Daguenet, Michel

    2006-10-01

    Sensitivity analysis is a mathematical tool, first developed for optimization methods, which aim is to characterize a system response through the variations of its output parameters following modifications imposed on the input parameters of the system. Such an analysis may quickly become laborious when the thermal model under consideration is complex or the number of input parameters is high. In this paper, we develop a mathematical model to analyse the heat exchanges in four different types of solar air collectors. When building this thermal model we show that for each collector, at quasi-steady state, the energy balance equations of the components of the collector cascade into a single first-order non-linear differential equation that is able to predict the thermal behaviour of the collector. Our heat transfer model clearly demonstrates the existence of an important dimensionless parameter, referred to as the thermal performance factor of the collector, that compares the useful thermal energy which can be extracted from the heater to the overall thermal losses of that collector for a given set of input parameters. A sensitivity analysis of our thermal model has been performed for the most significant input parameters such as the incident solar irradiation, the inlet fluid temperature, the air mass flow rate, the depth of the fluid channel, the number and nature of the transparent covers in order to measure the impact of each of these parameters on our model. An important result which can be drawn from this study is that the heat transfer model developed is robust enough to be used for thermal design studies of most known flat plate solar air heaters, but also of flat plate solar water collectors and linear solar concentrators.

  17. Characterization of a thermal power plant air heater washing waste: a case study from Iran.

    Science.gov (United States)

    Saeedi, M; Amini, H R

    2007-02-01

    In Iran most of the electricity is generated by thermal power plants. As a result of fuel oil burning in winter time, the air heaters of the boilers have to be washed and cleaned frequently. The wastewater originating from air heater washing is then treated in an effluent treatment plant by chemical precipitation followed by dewatering of the sludge produced. The resulting waste is classified as specific industrial waste that should be characterized in detail under the Waste Management Act of Iran. The quantity of this waste produced in the studied power plant is about 20 tonnes year(-1). In the present investigation, the first to be carried out in Iran, seven composite samples of dewatered sludge from air heater washing wastewater treatment were subjected to investigation of the physical properties, chemical composition and leaching properties. The most likely pollutants that were of concern in this study were heavy and other hazardous metals (Cd, Co, Cr, Mn, Ni, Pb, Zn and V). The results revealed that mean pH, wet and dry density and moisture content of the waste were 6.31, 1532 kg m(-30, 1879 kg m(-3) and 15.35%, respectively. Magnetite, SiO2, P2O5, CaO, Al2O3 and MgO were the main constituents of the waste with a weight percentage order of 68.88, 5.91, 3.39, 2.64, 2.59 and 1.76%, respectively. The toxicity characteristic leaching procedure test results for some heavy and other hazardous metals showed that mean elemental concentrations of Cd, Co, Cr, Mn, Ni, Pb, V and Zn in leachate were 0.06, 1.55, 5.49, 36.32, 209.10, 0.58, 314.06 and 24.84 mg L(-1), respectively. According to the Waste Management Act of Iran this waste should be classified as hazardous and should be disposed of in accordance with hazardous waste disposal regulations.

  18. The thermal performance of the two-pass, two-glass-cover solar air heater

    Energy Technology Data Exchange (ETDEWEB)

    Persad, P.; Sateunanathan, S.

    1983-08-01

    Analytic models are developed for the performance prediction of a two-glass-cover solar air heater operated in both the single-pass and two-pass modes. It is shown that the two-pass mode of operation is superior to the single-pass mode of operation over the range of collector inlet temperatures considered. This is seen to be mainly due to the fact that, in the two-pass mode of operation, the outer glass cover is cooled by the working fluid, thereby reducing the top losses. It is also shown that the performance in the two-pass mode of operation is independent of length, over the range of collector lengths considered, and that a critical plate spacing, dependent on the temperature level of operation of the collector, is indicated. Predicted values of performance are in good agreement with experimental results.

  19. Exergoeconomic Design of the Geometry of a Vertical, Three Steps, Tubular Air Heater

    Directory of Open Access Journals (Sweden)

    J.J. Marín–Hernández

    2009-10-01

    Full Text Available In this paper, the structural method of thermoeconomics is applied to find the optimal geometrical design to a vertical tubular air heater, whose original design is widely used on boilers installed on sugar mills. The objective function describes the running cost due to the temperature difference and pressure drop in function of the main geometrical parameters. The objective function is continuous in the interval of analysis and has a strong non linear behavior, then for solving it, the Optimization Toolbox from MATLAB 6.5 was used, through the function FMINCON, which uses an algorithm of medium scale, the Sequential Quadratic Programming (SQP and the Cuasi Newton method. The new design reduces the running cost of equipment 1,97 US$/s compared to the one of RETO 45–28 system.

  20. An experimental investigation of performance of a double pass solar air heater with thermal storage medium

    Directory of Open Access Journals (Sweden)

    Ali Hafiz Muhammad

    2015-01-01

    Full Text Available The performance of a double pass solar air heater was experimentally investigated using four different configurations. First configuration contained only absorber plate whereas copper tubes filled with thermal storage medium (paraffin wax were added on the absorber plate in the second configuration. Aluminum and steel rods as thermal enhancer were inserted in the middle of paraffin wax of each tube for configurations three and four respectively. Second configuration provided useful heat for about 1.5 hours after the sunset compared to first configuration. Configurations three and four provided useful heat for about 2 hours after the sunset. The maximum efficiency of about 96% was achieved using configuration three (i.e. using Aluminum rods in the middle of copper tubes filled with paraffin wax.

  1. Engineering analyses and design calculations of NASA, Langley Research Center hydrogen-air-vitiated heater with oxygen replenishment

    Science.gov (United States)

    1973-01-01

    The technical basis is presented for the design of the hydrogen-air-vitiated heater. The heater liner is subjected to a maximum thermal environment at a specified condition, where the combustion gas temperature, pressure and flow rate are 5000 F, 750 psia, and 11.0 lb/sec, respectively, and results in a heat flux of the order of 275 BTU/sec-sq ft. Cooling and stress analyses indicate that water is the logical choice for cooling of the combustor liner. A mixing analysis was undertaken to establish a good combination of combustor length and injector configuration. The analysis, using a conservative analytical approach, indicates a combustor length of the order of 5 ft combined with discrete fuel and oxidizer injection at an approximate 2-1/2 inch radial combustor position, and results in uniform combustion products at the heater exit for all specified envelope conditions.

  2. Optimal thermo-hydraulic performance of solar air heater having chamfered rib-groove roughness on absorber plate

    Directory of Open Access Journals (Sweden)

    Apurba Layek

    2010-07-01

    Full Text Available The use of an artificial roughness on a surface is an effective technique to enhance the rate of heat transfer to fluid flow in the duct of solar air heater. However, the increase in thermal energy gain is always accompanied by increase in pumping power. This paper is concerned with optimization of roughness parameters of solar air heater based on effective efficiency criterion. Effective efficiency of a solar air heater having repeated transverse chamfered rib–groove roughness on one broad wall has been computed using the correlations for heat transfer and friction factor developed within the investigated range of operating and system parameters. Roughness parameters viz. relative roughness pitch P/e, relative groove position g/P, chamfer angle , relative roughness height e/Dh and flow Reynolds number Re, have a combined effect on the heat transfer as well as fluid friction. The thermo-hydraulic performance of an air heater in terms of effective efficiency is determined on the basis of actual thermal energy gain subtracted by the primary energy required to generate power needed for pumping air through the roughened duct. Based on energy transfer mechanism to the absorber plate, a mathematical model is developed to compute effective efficiency. The selection of the optimal values of the roughness parameters involves the comparison of the enhancement of thermal performance and the increase of pumping losses as a result of using roughness in the collector system with that of the system without roughness. The effective efficiency criterion is maximized and reasonably optimized designs of roughness are found.

  3. Energy and exergy analysis of a two pass photovoltaic –thermal (PV/T) air heater

    Energy Technology Data Exchange (ETDEWEB)

    Srinivas, M.; Jayaraj, S. [Department of Mechanical Engineering, National Institute of Technology, Calicut-673601 (India)

    2013-07-01

    A double pass hybrid solar air (PV/T) heater with slats is designed and fabricated to study elaborately its thermal and electrical performance corresponding to the warm and humid environment. Air as a heat removing fluid is made to flow through upper and lower channels of the collector. The collector is designed in such way that the absorber plate is partially covered by solar cells. Thin metallic strips (called slats) are attached longitudinally at the bottom side of the absorber plate to improve the overall system performance (by increasing the cooling rate of the absorber plate). Thermal and electrical performances of the whole system at different cooling rates are presented. The exergy analysis of double pass hybrid solar air (PV/T) heater with slats has also been carried out. The instantaneous overall energy and overall exergy efficiency of the double pass hybrid (PV/T) solar air heater varies between 29 – 37 percent and 14-17 percent respectively. These obtained values are comparable with that of published results.

  4. Heat flux: thermohydraulic investigation of solar air heaters used in agro-industrial applications

    Science.gov (United States)

    Rahmati Aidinlou, H.; Nikbakht, A. M.

    2017-03-01

    A new design of solar air heater simulator is presented to comply with the extensive applications inagro-industry. A wise installation of increased heat transfer surface area provided uniform and efficient heat diffusion over the duct. Nusselt number and friction factor have been investigated based on the constant roughness parameters such as relative roughness height (e/D), relative roughness pitch (P/e), angle of attack (α) and aspect ratio with Reynolds numbers ranging from 5000 to 19,000 in the fully developed region. Heat fluxes of 800, 900 and 1000 Wm-2 were provided. The enhancement in friction factor is observed to be 3.1656, 3.47 and 3.0856 times, and for the Nusselt number either, augmentation is calculated to be 1.4437, 1.4963 and 1.535 times, respectively, over the smooth duct for 800, 900 and 1000 Wm-2 heat fluxes. Thermohydraulic performance is plotted versus the Reynolds number based on the aforementioned roughness parameters at varying heat fluxes. The results show up that thermohydraulic performance is found to be maximum for 1000 Wm-2 at the average Reynolds number of 5151. Based on the results, we can verify that the introduced solar simulator can help analyzing and developing solar collector installations at the simulated heat fluxes.

  5. Heat flux: thermohydraulic investigation of solar air heaters used in agro-industrial applications

    Science.gov (United States)

    Rahmati Aidinlou, H.; Nikbakht, A. M.

    2016-07-01

    A new design of solar air heater simulator is presented to comply with the extensive applications inagro-industry. A wise installation of increased heat transfer surface area provided uniform and efficient heat diffusion over the duct. Nusselt number and friction factor have been investigated based on the constant roughness parameters such as relative roughness height (e/D), relative roughness pitch (P/e), angle of attack (α) and aspect ratio with Reynolds numbers ranging from 5000 to 19,000 in the fully developed region. Heat fluxes of 800, 900 and 1000 Wm-2 were provided. The enhancement in friction factor is observed to be 3.1656, 3.47 and 3.0856 times, and for the Nusselt number either, augmentation is calculated to be 1.4437, 1.4963 and 1.535 times, respectively, over the smooth duct for 800, 900 and 1000 Wm-2 heat fluxes. Thermohydraulic performance is plotted versus the Reynolds number based on the aforementioned roughness parameters at varying heat fluxes. The results show up that thermohydraulic performance is found to be maximum for 1000 Wm-2 at the average Reynolds number of 5151. Based on the results, we can verify that the introduced solar simulator can help analyzing and developing solar collector installations at the simulated heat fluxes.

  6. Effect of Parametric Uncertainties, Variations, and Tolerances on Thermohydraulic Performance of Flat Plate Solar Air Heater

    Directory of Open Access Journals (Sweden)

    Rajendra Karwa

    2014-01-01

    Full Text Available The paper presents results of an analysis carried out using a mathematical model to find the effect of the uncertainties, variations, and tolerances in design and ambient parameters on the thermohydraulic performance of flat plate solar air heater. Analysis shows that, for the range of flow rates considered, a duct height of 10 mm is preferred from the thermohydraulic consideration. The thermal efficiency changes by about 2.6% on variation in the wind heat transfer coefficient, ±5 K variation in sky temperature affects the efficiency by about ±1.3%, and solar insolation variation from 500 to 1000 Wm−2 affects the efficiency by about −1.5 to 1.3% at the lowest flow rate of 0.01 kgs−1 m−2 of the absorber plate with black paint. In general, these effects reduce with increase in flow rate and are lower for collector with selective coating on the absorber plate surface. The tolerances in the duct height and absorber plate emissivity should be small while positive tolerance of 3° in the collector slope for winter operation and ±3° for year round operation, and a positive tolerance for the gap between the absorber plate and glass cover at nominal value of 40 mm are recommended.

  7. Commercialization of air conditioning heat pump/water heater. Final technical report, Volume 2: Appendix A through E

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-01-30

    This is the final technical report on a commercialization project for an air conditioning heat pump water heater. The objective of the project was to produce a saleable system which would be economically competitive with natural gas and cost effective with regard to initial cost versus annual operating costs. The development and commercialization of the system is described. Compiled data included in numerous figures, tables and graphs.

  8. Thermal storage heaters

    Energy Technology Data Exchange (ETDEWEB)

    Stokes, K.H.; Broadbent, J.T.

    1991-02-27

    A storage heater, providing heat by radiation, comprises an internal circuit for the passage of heated air. The heater comprises: a heat storage core, comprising heat storage rods heated by resistance wiring, and an air space around the rods, the air space forming an inner pathway of circuit; heat insulation around the core; and outer pathways adjacent outer walls of the heater. A damper is arranged at the top of the inner and outer pathways to control the communication between. The damper may be movably supported on a support part by robust bi-metallic strips wound with heater wires to control the bending of the strips. The storage heater may be supplied in kit form for the purchaser to assemble and to this end the heat storage rods may comprise particulate material poured into tubes, or liftable core units. Further heat insulation may be selectively positioned in the outer pathways to provide an even heat distribution. (author).

  9. Experimental study on split air conditioner with new hybrid equiment of energy storage and water heater all year round

    Energy Technology Data Exchange (ETDEWEB)

    Shaowei Wang; Zhenyan Liu [Shanghai Jiao Tong Univ. (China). School of Mechanical and Power Engineering; Yuan Li; Keke Zhao; Zhigang Wang [Qingdao Hisense Group Co. Ltd. (China)

    2005-11-01

    This paper presents a split air conditioner with a new hybrid equipment of energy storage and water heater all year round (ACWES). The authors made a special design on the storage tank to adjust the refrigerant capacity in the storage coils under different functions, instead of adding an accumulator to the system. An ACWES prototype, rebuilt from an original split air conditioner, has been finished, and experimental study of the operation processes of the prototype was done from which some important conclusions and suggestions have been made, which were helpful in the primary design and improvement of an ACWES system for potential users. (author)

  10. Experimental study on split air conditioner with new hybrid equipment of energy storage and water heater all year round

    Energy Technology Data Exchange (ETDEWEB)

    Wang Shaowei [School of Mechanical and Power Engineering, Shanghai Jiao Tong University, Shanghai 200030 (China)]. E-mail: wswtop@sjtu.edu.cn; Liu Zhenyan [School of Mechanical and Power Engineering, Shanghai Jiao Tong University, Shanghai 200030 (China); Li Yuan [Qingdao Hisense Group Co. Ltd., Qingdao 266030 (China); Zhao Keke [Qingdao Hisense Group Co. Ltd., Qingdao 266030 (China); Wang Zhigang [Qingdao Hisense Group Co. Ltd., Qingdao 266030 (China)

    2005-11-15

    This paper presents a split air conditioner with a new hybrid equipment of energy storage and water heater all year round (ACWES). The authors made a special design on the storage tank to adjust the refrigerant capacity in the storage coils under different functions, instead of adding an accumulator to the system. An ACWES prototype, rebuilt from an original split air conditioner, has been finished, and experimental study of the operation processes of the prototype was done from which some important conclusions and suggestions have been made, which were helpful in the primary design and improvement of an ACWES system for potential users.

  11. Experimental Investigation on Turbulent Convection in Solar Air Heater Channel Fitted with Delta Winglet Vortex Generator

    Institute of Scientific and Technical Information of China (English)

    Sompol Skullong; Pongjet Promvonge

    2014-01-01

    The paper presents an experimental study on the heat transfer and flow friction characteristics in a solar air heater channel fitted with delta-winglet type vortex generators (DWs). The experiments are conducted by vary-ing the airflow rate for Reynolds number in the range of 5000 to 24000 in the test section with a uniform heat-flux applied on the upper channel wall. Firstly, the DW pairs are mounted only at the entrance of the lower wall of the test channel (called DW-E) to create multiple vortex flows at the entry. The effect of two transverse pitches (RP=Pt/H=1 and 2) at three attack angles (α=30°, 45° and 60°) of the DW-E with its relative height, b/H=0.5 (half height of channel) is examined. Secondly, the 30° DWs with three different relative heights (b/H=0.3, 0.4 and 0.5) are placed on the upper wall only (absorber plate, called DW-A) of the test channel. The experimental result reveals that in the first case, the 60° DW-E at RP=1 provides the highest heat transfer and friction factor while the 30° DW-E at RP=1 performs overall better than the others. In the second case, the 30° DW-A at b/H=0.5 yields the highest heat transfer and friction factor but the best thermal performance is found at b/H=0.4.

  12. Performance prediction of solar air heater having roughened duct provided with transverse and inclined ribs as artificial roughness

    Energy Technology Data Exchange (ETDEWEB)

    Varun; Patnaik, Amar; Siddhartha [Mechanical Engg Dept., NIT, Hamirpur 177005 (India); Saini, R.P.; Singal, S.K. [AHEC, IIT, Roorkee 247667 (India)

    2009-12-15

    An experimental study has been carried out to investigate the effective efficiency of a solar air heater duct provided with transverse and inclined ribs as artificial roughness elements on the absorber plate. The range of parameters considered for the present investigation; Reynolds number (Re) 2000-14,000, relative roughness pitch (p/e) 3-8 and a fixed value of relative roughness height (e/D) of 0.030. The effective efficiency has been computed based on the experimentally determined values for the range of parameters considered. Further an attempt has also been made to optimize the thermal efficiency for the same system under similar conditions by Taguchi method. (author)

  13. Energy Efficiency Modelling of Residential Air Source Heat Pump Water Heater

    Directory of Open Access Journals (Sweden)

    Cong Toan Tran

    2016-03-01

    Full Text Available The heat pump water heater is one of the most energy efficient technologies for heating water for household use. The present work proposes a simplified model of coefficient of performance and examines its predictive capability. The model is based on polynomial functions where the variables are temperatures and the coefficients are derived from the Australian standard test data, using regression technics. The model enables to estimate the coefficient of performance of the same heat pump water heater under other test standards (i.e. US, Japanese, European and Korean standards. The resulting estimations over a heat-up phase and a full test cycle including a draw off pattern are in close agreement with the measured data. Thus the model allows manufacturers to avoid the need to carry out physical tests for some standards and to reduce product cost. The limitations of the methodology proposed are also discussed.

  14. Performance evaluation of a natural-convection solar air-heater with a rectangular-finned absorber plate

    Energy Technology Data Exchange (ETDEWEB)

    Fakoor Pakdaman, M.; Lashkari, A.; Basirat Tabrizi, H.; Hosseini, R. [Department of Mechanical Engineering, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of)

    2011-02-15

    This paper deals with an experimental investigation to evaluate different thermal characteristics of a natural-convection flat-plate solar air-heater with longitudinal rectangular fins array. Having determined the thermal performance of the system a Nusselt number correlation is presented for such finned duct devices. In the presented empirical model which may have industrial applications, solar radiation and ambient temperature have been considered as independent parameters. Other characteristics of the system such as different dimensionless variables, plates and outflow temperatures, efficiency, and mass flow rate have been empirically modeled based on these variables. The particular difference in this study in comparison with the other similar studies is the presentation of an empirical model for rectangular-finned solar air-heaters. This model proposes design concepts and rules of thumb, and demonstrates the calculations of the design parameters. Based on the order of magnitude analysis, solar radiation has been found to be the main parameter which characterizes the thermal behavior of the system. Besides, exergy analysis has been carried out, and optimum conditions in which the system has the highest performance have been determined. (author)

  15. Optimization of thermal performance of a smooth flat-plate solar air heater using teaching–learning-based optimization algorithm

    Directory of Open Access Journals (Sweden)

    R. Venkata Rao

    2015-12-01

    Full Text Available This paper presents the performance of teaching–learning-based optimization (TLBO algorithm to obtain the optimum set of design and operating parameters for a smooth flat plate solar air heater (SFPSAH. The TLBO algorithm is a recently proposed population-based algorithm, which simulates the teaching–learning process of the classroom. Maximization of thermal efficiency is considered as an objective function for the thermal performance of SFPSAH. The number of glass plates, irradiance, and the Reynolds number are considered as the design parameters and wind velocity, tilt angle, ambient temperature, and emissivity of the plate are considered as the operating parameters to obtain the thermal performance of the SFPSAH using the TLBO algorithm. The computational results have shown that the TLBO algorithm is better or competitive to other optimization algorithms recently reported in the literature for the considered problem.

  16. Technical support document: Energy efficiency standards for consumer products: Room air conditioners, water heaters, direct heating equipment, mobile home furnaces, kitchen ranges and ovens, pool heaters, fluorescent lamp ballasts and television sets. Volume 1, Methodology

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-01

    The Energy Policy and Conservation Act (P.L. 94-163), as amended, establishes energy conservation standards for 12 of the 13 types of consumer products specifically covered by the Act. The legislation requires the Department of Energy (DOE) to consider new or amended standards for these and other types of products at specified times. DOE is currently considering amending standards for seven types of products: water heaters, direct heating equipment, mobile home furnaces, pool heaters, room air conditioners, kitchen ranges and ovens (including microwave ovens), and fluorescent light ballasts and is considering establishing standards for television sets. This Technical Support Document presents the methodology, data, and results from the analysis of the energy and economic impacts of the proposed standards. This volume presents a general description of the analytic approach, including the structure of the major models.

  17. Mekanisme Proses Pemanasan Air Di Dalam Boiler Dengan Mempergunakan Heater Tambahan Untuk Efisiensi Pembakaran

    OpenAIRE

    Helmon Sihombing

    2010-01-01

    Pada proses pemanasan air, air yang berasal dari raw water (air tanah) tidak langsung dibakar didalam boiler. dalam hal ini digunakan peralatan instrumen Deaerator dan economizer yang berfungsi untuk pemanasan awal sebelum dibakar didalam boiler. Fungsi deaerator dan economizer ini adalah sebagai komponen pembantu untuk memanaskan air sebelum dibakar didalam boiler. Apabila pemanasan air langsung dilakukan didalam boiler maka akan membutuhkan waktu yang cukup lama dan menggunakan bahan b...

  18. 回转式空气预热器密封形式的改进%An Improvement on the Seal Form of a Rotary Air Heater

    Institute of Scientific and Technical Information of China (English)

    刘贵锋

    2001-01-01

    分析回转式空气预热器的漏风因素及现行密封形式的优缺点 ,提出回转式空气预热器“单密封”向“双密封”形式改进的理论依据及可行性研究。通过 几个发电厂实际改进效果表明,此项改进是改善回转式空气预热器漏风大的有效方法。%Based on the analysis of the air leakage factor of rotary air heaters and the me rits and demerits of traditional seal forms the author has presented the theoret ical basis for the improvement of a rotary air heater seal. This consists in inc orporating the change of its "single seal" form to a "dual seal" one. Furthermor e, a feasibility study concerning the above change is also given. Judging by the actual improvement attained at several power plants it can be shown that the me thod recommended by the author represents an effective approach for lowering th e air leakage rate of the rotary air heater.

  19. Experimental study of heat transfer enhancement in solar air heater with different angle of attack of V-down continuous ribs

    Science.gov (United States)

    Istanto, Tri; Danardono, Dominicus; Yaningsih, Indri; Wijayanta, Agung Tri

    2016-06-01

    In this paper, an experimental study on the effect of angle attack in V-down continuous ribs on heat transfer and friction factor in an artificially roughened air heater duct is presented. The electric heater with a constant heat flux as a simulation of the indoor testing solar air heater is used to heat the roughened part of rectangular duct while other parts were insulated. The system and operating conditions were used to decide the range of parameters for the study. The ratio of the width to height of the duct (W/H) was 12, the relative roughness pitch (p/e) was 10, the relative roughness height (e/Dh) was 0.033 and the angle of attack of flow (α) was 30-80°. The air flow rate corresponded to Reynolds number between 3500 -10,000. The result of heat transfer and friction factor had been compared to those for smooth duct under similar flow and thermal boundary condition. The thermo-hydraulic performance also had been considered. As a result, the maximum enhancement of Nusselt number (Nu) and friction factor(f) were 2.34 and 2.45 times, respectively. For each variation of angle attack of flow, the thermo-hydraulic performance has been compared and the result shows that a V-down continuous rib with the angle of attack of flow as 60° gave the best thermo-hydraulic performance.

  20. Solar air heaters for industrial drying; Aquecedor solar de ar para secagem industrial

    Energy Technology Data Exchange (ETDEWEB)

    Braga, Everaldo Mendes [Governo do Estado da Paraiba, Joao Pessoa, PB (Brazil). Secretaria de Planejamento e Gestao

    2008-07-01

    The objective of this study is to encourage the use of solar energy in industrial drying of fruits, with the producers poles, at the same time, promote the rational use of energy for heat, or replacing the hydroelectric and oil derivatives for this purpose. This study is presented in the following chapters: availability of solar energy; details of constructive solar heated air; drying fruit; market. (author)

  1. RESULTS OF INVESTIGATIONS ON THERMAL CHARACTERISTICS OF AIR HEATER BUNDLE MADE OF BIMETALLIC FINNED TUBES

    Directory of Open Access Journals (Sweden)

    V. B. Kuntysh

    2014-01-01

    Full Text Available The paper presents a scheme and description of a new aerodynamic stand that has a 300x300 mm cross-section operating channel. The stand is used for studying thermal and aerodynamic characteristics of bundles made of finned tubes of actual dimensions in crossflow. The paper provides results of an exploratory test pertaining to heat transfer and resistance of four row staggered bundle made of tubes with aluminium spiral fins having outside diameter of 26 mm which are used in the systems of ventilation, air-conditioning and heating of buildings and also in transport heat exchangers.

  2. Technical support document: Energy efficiency standards for consumer products: Room air conditioners, water heaters, direct heating equipment, mobile home furnaces, kitchen ranges and ovens, pool heaters, fluorescent lamp ballasts and television sets. Volume 3, Water heaters, pool heaters, direct heating equipment, and mobile home furnaces

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-01

    This is Volume 3 in a series of documents on energy efficiency of consumer products. This volume discusses energy efficiency of water heaters. Water heaters are defined by NAECA as products that utilize oil, gas, or electricity to heat potable water for use outside the heater upon demand. These are major appliances, which use a large portion (18% on average) of total energy consumed per household (1). They differ from most other appliances in that they are usually installed in obscure locations as part of the plumbing and are ignored until they fail. Residential water heaters are capable of heating water up to 180{degrees}F, although the setpoints are usually set lower.

  3. Numerical analysis of flow in a solar heater of air packing with shavings; Analisis numerico del flujo en un calentador solar de aire empacado con viruta

    Energy Technology Data Exchange (ETDEWEB)

    Lopez C, Raymundo; Morales G, Juan R; Diaz C, Alen; Lara V, Araceli; Lizardi R, Arturo [Universidad Autonoma Metropolitana-Azcapotzalco, Mexico, D.F. (Mexico); Vaca M, Mabel [UNAM, Mexico, D.F. (Mexico)

    2000-07-01

    The temperature distribution of air through a solar heater is determined by means of the equations of heat, mass, momentum, and energy conservation. The solution is obtained by means of the numeric model of finite volume, using the CFC2000 software, V. 3.3. The studied flow is laminar. The temperature distribution resulted quite similar for different Reynolds numbers; the greatest difference was less than 4 Celsius degrees, for similar ranges of solar radiation. The influence of the separation that exists between the clear cover and the free surface of the material used as thermal summit (b) was analyzed. A difference up to 41 Celsius degrees for a Reynolds number of 1000 and values of b between 3 and 7 cm. For a Reynolds of 2000, the difference was of 29 Celsius degrees, in the same range of b. [Spanish] Se determinan la distribucion de temperaturas del aire, a lo largo de un calentador solar, aplicando las ecuaciones de conservacion de masa, cantidad de movimiento y energia. La solucion se obtiene con el modelo numerico de volumen finito y la utilizacion del programa de computadora llamado CFC2000 version 3.3. El flujo estudiado es del tipo laminar. La distribucion de temperaturas resulto ser muy semejante para diferentes valores del numero de Reynolds, la diferencia mayor resulto menor a 4 grados Celsius, para rangos similares de radiacion solar. Se analizo la influencia de la separacion que existe entre la cubierta transparente y la superficie libre del material que sirve como almacen termico (b). Se encontro una diferencia maxima de hasta 41 grados celsius para un numero de Reynolds de 1000 y los valores de b entre 3 y 7 cm. Cuando el Reynolds fue de 2000 la diferencia fue de 29 grados Celsius, en el mismo rango de b.

  4. Development of Air Source Heat Pump Water Heater Performance Test Rig%空气源热泵热水器性能测试系统实验台的研制

    Institute of Scientific and Technical Information of China (English)

    刘笑笑; 丁强

    2015-01-01

    为了满足空气源热泵热水器性能测试的需要,基于对空气源热泵热水器原理、工作特点、热工测试技术、工业控制技术、上位机编写技术等基础,严格参照空气源热泵热水器的相关国家标准设计了一套空气源热泵热水器性能测试系统。该系统不仅能自动计算出被测空气源热泵热水器的性能参数,且具有良好的人机交互界面、可操作性强、性能可靠等优点。%In order to meet the needs of the air source heat pump water heater performance test,according to the work-ing principle of the air source heat pump water heater,working characteristics,thermal testing technology,industrial control technology,computer technology and other related technology,strictly according to the air source heat pump water heater national standards to design a set of water heater performance of air source heat pump test system,it can calculate the performance parameters of the tested air source heat pump water heater automatical y.

  5. 49 CFR 393.77 - Heaters.

    Science.gov (United States)

    2010-10-01

    ... all hot water and steam heater systems shall be specifically designed and constructed for that purpose... when used for heating the cargo of tank motor vehicles. (3) Heaters permitting fuel leakage. Any type... air, heated or to be heated, from the engine compartment or from direct contact with any portion...

  6. 40 CFR 63.988 - Incinerators, boilers, and process heaters.

    Science.gov (United States)

    2010-07-01

    ... bed. (3) Where a boiler or process heater of less than 44 megawatts (150 million British thermal units... heaters. 63.988 Section 63.988 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Routing to a Fuel Gas System or a Process § 63.988 Incinerators, boilers, and process heaters....

  7. 全玻璃真空管太阳能空气集热器热性能试验方法研究%STUDY ON MEASUREMENT OF THERMAL PERFORMANCE OF ALL-GLASS EVACUATED TUBULAR SOLAR AIR HEATER

    Institute of Scientific and Technical Information of China (English)

    王志峰

    2001-01-01

    全玻璃真空管空气集热器是一种热损较小的太阳能空气加热装置。该文对该类集热器热性能评价方法进行了研究,并对集热器的时间常数、热延迟常数、角系数修正因子及瞬时热效率的实验方法进行了初步的实验研究。研究表明,用热延迟常数比时间常数能更好地反映真空管集热器的热性能,真空管集热器的角系数修正因子在垂直入射时最小。%Evacuated tubular solar collector is good for solar air heater as its low heat loss.A study on the thermal performance of the solar air heater is presented.The methods to test the time constant,resident time,incident angular modifier and instantaneous thermal efficiency are suggested.The resident time would be better than time constant to represent the thermal properties of the solar air heater.The incident angular modifier will be minimal at solar noon for the evacuated tubular solar air heater.

  8. CFD analysis to study effect of circular vortex generator placed in inlet section to investigate heat transfer aspects of solar air heater.

    Science.gov (United States)

    Gawande, Vipin B; Dhoble, A S; Zodpe, D B

    2014-01-01

    CFD analysis of 2-dimensional artificially roughened solar air heater duct with additional circular vortex generator, inserted in inlet section is carried out. Circular transverse ribs on the absorber plate are placed as usual. The analysis is done to investigate the effect of inserting additional vortex generator on the heat transfer and flow friction characteristics inside the solar air heater duct. This investigation covers relative roughness pitch in the range of 10 ≤ P/e ≤ 25 and relevant Reynolds numbers in the range of 3800 ≤ Re ≤ 18000. Relative roughness height (e/D) is kept constant as 0.03 for analysis. The turbulence created due to additional circular vortex generator increases the heat transfer rate and at the same time there is also increase in friction factor values. For combined arrangement of ribs and vortex generator, maximum Nusselt number is found to be 2.05 times that of the smooth duct. The enhancement in Nusselt number with ribs and additional vortex generator is found to be 1.06 times that of duct using ribs alone. The maximum increase in friction factor with ribs and circular vortex generator is found to be 2.91 times that of the smooth duct. Friction factor in a combined arrangement is 1.114 times that in a duct with ribs alone on the absorber plate. The augmentation in Thermal Enhancement Factor (TEF) with vortex generator in inlet section is found to be 1.06 times more than with circular ribs alone on the absorber plate.

  9. Thermal performance of new flat plate solar air heater based on micro-heat pipe arrays (MHPA)%微热管阵列式太阳能平板空气集热器集热性能

    Institute of Scientific and Technical Information of China (English)

    朱婷婷; 刁彦华; 赵耀华; 马骋; 李凤飞

    2016-01-01

    In common types of flat-plate solar air heaters, the uneven flow and heat exchange between air and an absorber plate poses a problem. To resolve this problem, this paper proposed a novel type of flat-plate solar air heater based on micro-heat pipe arrays (MHPA). An investigation was carried out on the design, thermal performance and flow resistance characteristic of the novel heater based on micro-heat pipe arrays. The new air collector consists of 15 MHPAs with V-shaped fins attached to the heat release (condenser) section, absorber film, insulation board, bottom plate, and air ventilation and heat exchange section. The components of the heater include the toughened glass cover, air layer (35 mm), MHPA-absorber plate, thermal insulation layer, and the back board. Solar energy is absorbed by the MHPA evaporator section with the organic combination of high efficiency absorber film, which formed a heat pipe effect within each micro heat pipe arrays. The heat has been released to the air in the ventilation and heat exchange section of the heater, whereas the air was eventually warmed. Simultaneously, the working medium in MHPA proceeds continuous phase transition cycle and continuously passes solar radiation heat to air in the air duct with high efficiency. The MHPA heat-absorbing plate core can realize the whole area of heat absorption, high efficient heat transmission, and large surface of heat release. The total solar energy is received by the heater, and some energy is transferred to the air flow in the air duct as useful energy; the remaining energy is lost mainly through the glass cover, frames, bottom plate, and air duct. The heat loss through the frames and the air duct can be ignored because of good heat preservation condition. So the glass cover becomes the main source of heat loss. Thermal analysis shows that heat loss through the glass cover occupies the largest proportion of the total heat loss of the heater.To test the new heater thermal efficiency and

  10. Particulate matter sensor with a heater

    Science.gov (United States)

    Hall, Matthew

    2011-08-16

    An apparatus to detect particulate matter. The apparatus includes a sensor electrode, a shroud, and a heater. The electrode measures a chemical composition within an exhaust stream. The shroud surrounds at least a portion of the sensor electrode, exclusive of a distal end of the sensor electrode exposed to the exhaust stream. The shroud defines an air gap between the sensor electrode and the shroud and an opening toward the distal end of the sensor electrode. The heater is mounted relative to the sensor electrode. The heater burns off particulate matter in the air gap between the sensor electrode and the shroud.

  11. SCR脱硝空预器防腐及柔性接触密封改造%Anticorrosion and Flexible Contact Seal Transformation of the SCR Denitration Air Heater

    Institute of Scientific and Technical Information of China (English)

    欧阳葵

    2014-01-01

    After using SCR denitration in thermal power enterprises, low temperature corrosion will also occur on rotary air heater. In this paper the rotary air heater corrosion protection technology reform measures are studied, the principle and characteristics of flexible contact seal technology are analyzed, the modification of air heater anticor-rosion and the air leakage reduction is completed, and the seal transformation efficiency analysis is conducted. The running results show that prevent anticorrosion and flexible contact seal modification can prevent the corrosion at low temperature, reduce the air leakage in air heater, and obtain remarkable economic and social benefits.%火力发电企业在采用SCR脱硝后,回转式空预器也会发生低温腐蚀。研究了回转式空预器防腐改造技术措施,分析了柔性接触式密封技术的原理及特点,进行了空预器防腐及减小漏风改造,并进行了密封改造的效益分析。运行结果表明,经过防腐及柔性接触式密封改造后,可防止低温腐蚀,且大幅度降低空气预热器漏风,获得较显著的经济效益和社会效益。

  12. Packaged die heater

    Science.gov (United States)

    Spielberger, Richard; Ohme, Bruce Walker; Jensen, Ronald J.

    2011-06-21

    A heater for heating packaged die for burn-in and heat testing is described. The heater may be a ceramic-type heater with a metal filament. The heater may be incorporated into the integrated circuit package as an additional ceramic layer of the package, or may be an external heater placed in contact with the package to heat the die. Many different types of integrated circuit packages may be accommodated. The method provides increased energy efficiency for heating the die while reducing temperature stresses on testing equipment. The method allows the use of multiple heaters to heat die to different temperatures. Faulty die may be heated to weaken die attach material to facilitate removal of the die. The heater filament or a separate temperature thermistor located in the package may be used to accurately measure die temperature.

  13. An investigation of heat transfer augmentation and friction characteristics in solar air heater duct with V-shaped wire as artificial roughness on absorber plate

    Energy Technology Data Exchange (ETDEWEB)

    Madhukeshwara, N. [Department of Mechanical Engineering, B.I.E.T, Davanagere, Karnataka (India); Prakash, E.S. [Department of Studies in Mechanical Engineering, U.B.D.T.C.E, Davanagere, Karnataka (India)

    2013-07-01

    An experimental investigation of heat transfer augmentation and friction characteristics of fully developed turbulent flow in a rectangular duct of solar air heater with absorber plate having V-shaped wire ribs as artificial roughness on its underside is carried out. The investigation covers wide range of different parameters of wire ribbed roughness: relative roughness pitch (p/e) from 10 to 40, relative roughness height (e/Dh) from 0.01 to 0.04 and angle of attack of flow from 20° to 90°. Duct aspect ratio (W/B) is kept 5 and Reynolds number (Re) is varied from 2,500 to 8,500. The heat transfer and friction factor values obtained are compared with those of smooth duct under similar flow conditions. Expressions are developed for Nusselt number and friction factor for the roughness geometry. Enhancement of Nusselt number and friction factor for roughened duct are 1.5 and 2.7 times of smooth duct respectively.

  14. An investigation of heat transfer augmentation and friction characteristics in solar air heater duct with V-shaped wire as artificial roughness on absorber plate

    Directory of Open Access Journals (Sweden)

    Madhukeshwara N., E. S. Prakash

    2013-01-01

    Full Text Available An experimental investigation of heat transfer augmentation and friction characteristics of fully developed turbulent flow in a rectangular duct of solar air heater with absorber plate having V-shaped wire ribs as artificial roughness on its underside is carried out. The investigation covers wide range of different parameters of wire ribbed roughness: relative roughness pitch (p/e from 10 to 40, relative roughness height (e/Dh from 0.01 to 0.04 and angle of attack of flow from 20° to 90°. Duct aspect ratio (W/B is kept 5 and Reynolds number (Re is varied from 2,500 to 8,500. The heat transfer and friction factor values obtained are compared with those of smooth duct under similar flow conditions. Expressions are developed for Nusselt number and friction factor for the roughness geometry. Enhancement of Nusselt number and friction factor for roughened duct are 1.5 and 2.7 times of smooth duct respectively.

  15. 空气能热泵热水机不锈钢内胆焊接工艺优化研究%Optimization of Stainless Steel Tank Welding Procedure in Air-source Heat Pump Water Heater

    Institute of Scientific and Technical Information of China (English)

    刘树清; 余文鹏

    2015-01-01

    The stainless steel tank in air-source heat pump water heater was an container which bear pressure and heat. It is the key component of the air-source heat pump water heater and suffered sever environment at working condition. Welding joint corrosion is the Achilles' heel of stainless tank service life at existing welding procedure. This condition restricted air-source heat pump water heater putting into use and popularize widely. Optimization of stainless steel tank welding procedure in air-source heat pump water heater has been applied several aspect and enhance the service life obviously.%空气能热泵热水器保温水箱的不锈钢内胆是一个承压承热的容器,是热水机产品的关键构件,其工作环境较为恶劣。在现有的焊接工艺条件下,不锈钢内胆的各个焊缝处的腐蚀失效是整个水箱寿命的短板,严重影响了空气能热泵热水机这种新型的节能减排产品的使用和发展。因此对空气能热泵热水机的焊接工艺作了几个方面的优化调整,使得不锈钢内胆的使用寿命得到了较大幅度的提高,取得了良好的效果。

  16. R and D of a house total system. Research on new functions and improvement of controllability of the regenerative air-heater; Jutaku total sytem no kenkyu kaihatsu. Chikunetsu danboki no aratana kino oyobi seigyosei no kojo kenkyu.

    Energy Technology Data Exchange (ETDEWEB)

    Inaba, S.; Takeyama, S. [Hokkaido Electric Power Co. Inc., Sapporo (Japan)

    1995-06-14

    Research was made on new functions and control of the already developed regenerative air-heater to maintain a more comfortable air-heated environment through the further improvement in method to use it. In the regenerative air-heater, the night power of low cost in the electric rate schedule is stored as thermal energy in its internal regenerative refractories, and when necessary, taken out to heat the air. To improve the switching operation for it, eight different switches were made selectable to set the initial condition. Released against the quantitative shortage of stored heat, its function of continuous operation was automated by putting the heating conditions in order. As measures against the absence, the house was prevented from cooling as a whole by continuing the air-heating operation at low temperatures. The air-heating operation was made controllable by three ways with a telecontrol system connected through the communication line. Also applied to decrease the deviation in room temperature, the fuzzy control could do the conventional deviation of {plus_minus}1{degree}C to within {plus_minus}0.5{degree}C with the fan noise abated. 3 refs., 10 figs., 5 tabs.

  17. Grouped exposed metal heaters

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar, Harold J [Bellaire, TX; Coit, William George [Bellaire, TX; Griffin, Peter Terry [Brixham, GB; Hamilton, Paul Taylor [Houston, TX; Hsu, Chia-Fu [Granada Hills, CA; Mason, Stanley Leroy [Allen, TX; Samuel, Allan James [Kular Lumpar, ML; Watkins, Ronnie Wade [Cypress, TX

    2012-07-31

    A system for treating a hydrocarbon containing formation is described. The system includes two or more groups of elongated heaters. The group includes two or more heaters placed in two or more openings in the formation. The heaters in the group are electrically coupled below the surface of the formation. The openings include at least partially uncased wellbores in a hydrocarbon layer of the formation. The groups are electrically configured such that current flow through the formation between at least two groups is inhibited. The heaters are configured to provide heat to the formation.

  18. Grouped exposed metal heaters

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar, Harold J. (Bellaire, TX); Coit, William George (Bellaire, TX); Griffin, Peter Terry (Brixham, GB); Hamilton, Paul Taylor (Houston, TX); Hsu, Chia-Fu (Granada Hills, CA); Mason, Stanley Leroy (Allen, TX); Samuel, Allan James (Kular Lumpar, MY); Watkins, Ronnie Wade (Cypress, TX)

    2010-11-09

    A system for treating a hydrocarbon containing formation is described. The system includes two or more groups of elongated heaters. The group includes two or more heaters placed in two or more openings in the formation. The heaters in the group are electrically coupled below the surface of the formation. The openings include at least partially uncased wellbores in a hydrocarbon layer of the formation. The groups are electrically configured such that current flow through the formation between at least two groups is inhibited. The heaters are configured to provide heat to the formation.

  19. A New Type of Complex System of Solar Energy Air Source Heat Pump Water Heater%一种新型的太阳能——空气源复合热泵热水器系统

    Institute of Scientific and Technical Information of China (English)

    王军军

    2011-01-01

    基于太阳能热利用技术、空气源热泵热水器理论,介绍了一种将太阳能与空气源相结合的双热源热泵热水器系统。该系统可充分利用太阳能加热生活用热水,辅以空气源热泵来满足太阳辐射照度不足时的用热水需求,同时用太阳能辅助加热来解决低温环境下空气源热泵运行工况恶劣的问题。系统充分利用了低品位的太阳能,保证稳定性,又可提高夏季阴雨天气、过渡季节及冬季太阳能热水器的热水温度,对于节约能源和环境保护具有重要意义。%Based on the technology of solar thermal and the theory of air-source heat pump water heater, a combined water heater system about solar and air source heat pump was introduced. The system Could make full use of solar energy to heat domestic hot water, combined with air-source heat pump to meet the shortage of solar irradiance when the hot water demand, and the auxiliary heating with solar energy to solve the problems of air source heat pump operating conditions in low temperature. The system took full use of the low-grade solar energy, and stability could be assured. And it could improve the temperature of the water in solar water heaters in rainy summers, transition seasons and winters. The system had significance for energy conservation and environmental protection.

  20. 14 CFR 25.859 - Combustion heater fire protection.

    Science.gov (United States)

    2010-01-01

    ... passages. (b) Ventilating air ducts. Each ventilating air duct passing through any fire zone must be..., the ventilating air duct downstream of each heater must be fireproof for a distance great enough to... fluids or vapors into the ventilating airstream. (c) Combustion air ducts. Each combustion air duct...

  1. 14 CFR 23.859 - Combustion heater fire protection.

    Science.gov (United States)

    2010-01-01

    ... passage that surrounds the combustion chamber. (b) Ventilating air ducts. Each ventilating air duct... fireproof valves or by equally effective means, the ventilating air duct downstream of each heater must be...) Combustion air ducts. Each combustion air duct must be fireproof for a distance great enough to...

  2. Analysis of liquid and gaseous oxygen influence on the combustion flow field of air heater%液氧与气氧对空气加热器燃烧流场的影响分析

    Institute of Scientific and Technical Information of China (English)

    冯军红; 沈赤兵; 赵芳

    2012-01-01

    The evaluation index, such as spray combustion, gas mixing and nozzle non-uniformity of air heater based on the combustor of liquid rocket engine, was studied with numerical simulation. The difference between the injectors with ethanol/liquid oxygen/air and the injectors with ethanol/gaseous oxygen/air in the combustion flow field was discussed and analyzed. Two cases were designed by changing the characteristic length of combustor, and the performance of air heaters were investigated by numerical simulation. The results show that, the flame structure is affected obviously by the phase of oxygen. The length of flame with liquid oxygen is larger than that of gaseous oxygen. More hot gas fills in the recirculation zone in the forepart of combustor with gaseous oxygen case, which increases the gas temperature near the faceplate, and worsens the thermal environment on the faceplate. The high quality flow field on the nozzle exit is obtained with the designed air heater. The characteristic length of air heater with gaseous oxygen is at least a quarter less than that of air heater with liquid oxygen to keep the good uniformity of nozzle exit.%针对一种基于液体火箭发动机燃烧室结构的空气加热器,采用数值仿真技术研究了加热器内部喷雾燃烧、燃气掺混以及出口流场分布等参数.分析对比了采用酒精/液氧/空气与酒精/气氧/空气两种不同氧化剂物态三组元同轴直流式喷嘴所得到的燃烧流场的区别,并通过改变燃烧室特征长度,分析了两种计算工况的加热器的性能差异.结果表明,喷入氧化剂的物态对燃烧流场影响较大,采用液氧喷嘴的火焰较长,气氧喷嘴的火焰分布较宽,且相对于液氧喷嘴,气氧喷嘴的燃烧室前端回流区由于掺混较多的燃气,导致喷注面板附近燃气温度较高,面板承热压力较大.设计的加热器均可保证两种喷嘴的出口流场品质较高,在保证流场出口品质的原则上,气氧喷

  3. Performance characterization of a hydrogen catalytic heater.

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Terry Alan; Kanouff, Michael P.

    2010-04-01

    This report describes the performance of a high efficiency, compact heater that uses the catalytic oxidation of hydrogen to provide heat to the GM Hydrogen Storage Demonstration System. The heater was designed to transfer up to 30 kW of heat from the catalytic reaction to a circulating heat transfer fluid. The fluid then transfers the heat to one or more of the four hydrogen storage modules that make up the Demonstration System to drive off the chemically bound hydrogen. The heater consists of three main parts: (1) the reactor, (2) the gas heat recuperator, and (3) oil and gas flow distribution manifolds. The reactor and recuperator are integrated, compact, finned-plate heat exchangers to maximize heat transfer efficiency and minimize mass and volume. Detailed, three-dimensional, multi-physics computational models were used to design and optimize the system. At full power the heater was able to catalytically combust a 10% hydrogen/air mixture flowing at over 80 cubic feet per minute and transfer 30 kW of heat to a 30 gallon per minute flow of oil over a temperature range from 100 C to 220 C. The total efficiency of the catalytic heater, defined as the heat transferred to the oil divided by the inlet hydrogen chemical energy, was characterized and methods for improvement were investigated.

  4. Coaxial Electric Heaters

    Science.gov (United States)

    Strekalov, Dmitry; Matsko, Andrey; Savchenkov, Anatoliy; Maleki, Lute

    2008-01-01

    Coaxial electric heaters have been conceived for use in highly sensitive instruments in which there are requirements for compact heaters but stray magnetic fields associated with heater electric currents would adversely affect operation. Such instruments include atomic clocks and magnetometers that utilize heated atomic-sample cells, wherein stray magnetic fields at picotesla levels could introduce systematic errors into instrument readings. A coaxial electric heater is essentially an axisymmetric coaxial cable, the outer conductor of which is deliberately made highly electrically resistive so that it can serve as a heating element. As in the cases of other axisymmetric coaxial cables, the equal magnitude electric currents flowing in opposite directions along the inner and outer conductors give rise to zero net magnetic field outside the outer conductor. Hence, a coaxial electric heater can be placed near an atomic-sample cell or other sensitive device. A coaxial electric heater can be fabricated from an insulated copper wire, the copper core of which serves as the inner conductor. For example, in one approach, the insulated wire is dipped in a colloidal graphite emulsion, then the emulsion-coated wire is dried to form a thin, uniform, highly electrically resistive film that serves as the outer conductor. Then the film is coated with a protective layer of high-temperature epoxy except at the end to be electrically connected to the power supply. Next, the insulation is stripped from the wire at that end. Finally, electrical leads from the heater power supply are attached to the exposed portions of the wire and the resistive film. The resistance of the graphite film can be tailored via its thickness. Alternatively, the film can be made from an electrically conductive paint, other than a colloidal graphite emulsion, chosen to impart the desired resistance. Yet another alternative is to tailor the resistance of a graphite film by exploiting the fact that its resistance

  5. Note: Improved heater design for high-temperature hollow cathodes

    Science.gov (United States)

    McDonald, M. S.; Gallimore, A. D.; Goebel, D. M.

    2017-02-01

    We present an improved heater design for thermionic cathodes using a rhenium filament encased in a boron nitride ceramic sleeve. This heater is relatively simple to fabricate, yet has been successfully used to reliably and repeatably light a lanthanum hexaboride (LaB6) hollow cathode based on a previously published design without noticeable filament degradation over hundreds of hours of operation. The high decomposition temperature of boron nitride (2800 C for inert environments) and melting point for rhenium (3180 C) make this heater especially attractive for use with LaB6, which may require operating temperatures upwards of 1700 C. While boron nitride decomposes in air above 1000 C, the heater was used only at vacuum with an inert gas discharge, and no degradation was observed. Limitations of current state of the art cathode heaters are also discussed and compared with the rhenium-boron nitride combination.

  6. 欧盟空气源热泵(静态)热水器生态设计测试研究%Study of the Test about Ecodesign of Air Source Heat Pump (Static) Water Heater in European Market

    Institute of Scientific and Technical Information of China (English)

    马洁丹; 臧松彦

    2015-01-01

    本文结合法规EU No.812/2013、 EU No.814/2013和标准EN 16147:2011对空气源热泵热水器的ERP测试方法和要求进行分析和总结,并提出测试过程中的各个注意事项,以便读者更好了解新法规对热泵能效的测试要求。%This paper analyzed and summarized the ERP test of Air source heat pump water heater, with the code of EU No.812/2013, EU No.814/2013 and the standard of EN 16147: 2011, and brought forward notice of the test, for the reader knowing more about the energy efficiency test of heat pump.

  7. Firebox modeling of SRT cracking heaters

    Energy Technology Data Exchange (ETDEWEB)

    Sundaram, K.M.; Albano, J.V. [ABB Lummus Crest Inc., Bloomfield, NJ (United States)

    1994-12-31

    Thermal cracking of hydrocarbons remains the most economically attractive route for the production of ethylene. The heat for the endothermic cracking reaction is supplied in high capacity fired heaters which are designed specifically to have high selectivity to olefins. In the cracking process, coke is deposited within the tubes of the radiant coil. The rate of coke deposition in a cracking furnace is a function not only of process conditions but of other factors as well. High tube metal temperatures in certain areas of the coil or hot spots can cause locally high coking rate leading to partial blockage of the tubes and consequently, short runs. The small diameter tubes used in modern high selectivity heaters are more sensitive than older large tube designs. The occurrence of these hot zones is a strong function of fireside conditions. For satisfactory performance, the heat flux profile in a cracking heater must be maintained as uniform as possible. In addition, it is important to minimize the variation of process temperatures entering the various cracking coils. These fireside variables are not only a function of the type of burners, excess air, type of fuel(s) and distribution of air and fuel but depend significantly on the air and flue gas flow patterns associated with the firebox, i.e., the firebox aerodynamics. Poor aerodynamics can adversely affect firing patterns and hence heat flux profiles in commercial furnaces. A variety of modeling techniques have been used to evaluate the firebox aerodynamics of Lummus, Short Residence Time, cracking heaters. These include flow visualization, physical cold flow modeling, and computational techniques. These approaches are discussed in this paper.

  8. 热一次风加热器与低压省煤器的联合应用%Combined application of hot primary air heater and low pressure economizer

    Institute of Scientific and Technical Information of China (English)

    薛宁; 印旭洋; 王春昌

    2015-01-01

    A hot primary air heater (HPAH)technology was introduced,which uses the heater installed on the hot primary air duct to heat condensation water,so the steam extraction amount can be reduced to in﹣crease the turbine's work ability,thus to save the energy.Moreover,the combined application of the HPAH and low pressure economizer (LPE)was studied,and the its application in a 600MW unit was designed and calculated.The results show that,the HPAH is suitable for units with large quantity of cool air,high ex﹣haust temperature and surplus pressure margin of primary draft fan.The energy conservation potential of the LPE is lower at low load,but the HPAH is on the contrary.The combined application of them can save net coal consumption rate by more than 3 g/(kW•h)at both low and high load.%介绍了一种热一次风加热器技术,该技术通过在热一次风道上增加换热设备,加热凝结水,利用凝结水回收热量,减少汽轮机抽汽量,增加汽轮机做功能力,实现节能。同时,对热一次风加热器与低压省煤器联合应用技术进行了研究,并对某600 MW 机组的联合应用方案进行了设计与计算。结果表明:热一次风加热器技术适用于制粉系统冷风量较大、排烟温度高且一次风机压力具有一定裕量的机组;低压省煤器技术在低负荷时节能潜力降低,而热风加热器技术随负荷降低,节能能力增强,两者联合应用方案在机组高、低负荷段均可节省供电煤耗3 g/(kW•h)以上,节能效果明显。

  9. Compact instantaneous water heater

    Energy Technology Data Exchange (ETDEWEB)

    Azevedo, Jorge G.W.; Machado, Antonio R.; Ferraz, Andre D.; Rocha, Ivan C.C. da; Konishi, Ricardo [Companhia de Gas de Santa Catarina (SCGAS), Florianopolis, SC (Brazil); Lehmkuhl, Willian A.; Francisco Jr, Roberto W.; Hatanaka, Ricardo L.; Pereira, Fernando M.; Oliveira, Amir A.M. [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil)

    2012-07-01

    This paper presents an experimental study of combustion in an inert porous medium in a liquid heating device application. This project aims to increase efficiency in the application of natural gas in residential and commercial sectors with the use of advanced combustion and heat transfer. The goal is to facilitate the development of a high performance compact water heater allowing hot water supply for up to two simultaneous showers. The experiment consists in a cylindrical porous burner with an integrated annular water heat exchanger. The reactants were injected radially into the burner and the flame stabilizes within the porous matrix. The water circulates in a coiled pipe positioned at the center of the burner. This configuration allows for heat transfer by conduction and radiation from the solid matrix to the heat exchanger. This article presented preliminary experimental results of a new water heater based on an annular porous burner. The range of equivalence ratios tested varied from 0.65 to 0.8. The power range was varied from 3 to 5 kW. Increasing the equivalence ratio or decreasing the total power input of the burner resulted in increased thermal efficiencies of the water heater. Thermal efficiencies varying from 60 to 92% were obtained. The condition for the goal of a comfortable bath was 20 deg C for 8-12 L/min. This preliminary prototype has achieved water temperature of 11deg C for 5 L/min. Further optimizations will be necessary in order to achieve intense heating with high thermal efficiency. (author)

  10. Subsurface heaters with low sulfidation rates

    Energy Technology Data Exchange (ETDEWEB)

    John, Randy Carl; Vinegar, Harold J

    2013-12-10

    A system for heating a hydrocarbon containing formation includes a heater having an elongated ferromagnetic metal heater section. The heater is located in an opening in a formation. The heater section is configured to heat the hydrocarbon containing formation. The exposed ferromagnetic metal has a sulfidation rate that goes down with increasing temperature of the heater, when the heater is in a selected temperature range.

  11. 46 CFR 119.320 - Water heaters.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Water heaters. 119.320 Section 119.320 Shipping COAST... Machinery § 119.320 Water heaters. (a) A water heater must meet the requirements of Parts 53 and 63 in... electric water heater is also acceptable if it: (1) Has a capacity of not more than 454 liters (120...

  12. 46 CFR 182.320 - Water heaters.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Water heaters. 182.320 Section 182.320 Shipping COAST...) MACHINERY INSTALLATION Auxiliary Machinery § 182.320 Water heaters. (a) A water heater must meet the...), except that an electric water heater is also acceptable if it: (1) Has a capacity of not more than...

  13. Heat Pump Water Heaters and American Homes: A Good Fit?

    Energy Technology Data Exchange (ETDEWEB)

    Franco, Victor; Lekov, Alex; Meyers, Steve; Letschert, Virginie

    2010-05-14

    Heat pump water heaters (HPWHs) are over twice as energy-efficient as conventional electric resistance water heaters, with the potential to save substantial amounts of electricity. Drawing on analysis conducted for the U.S. Department of Energy's recently-concluded rulemaking on amended standards for water heaters, this paper evaluates key issues that will determine how well, and to what extent, this technology will fit in American homes. The key issues include: 1) equipment cost of HPWHs; 2) cooling of the indoor environment by HPWHs; 3) size and air flow requirements of HPWHs; 4) performance of HPWH under different climate conditions and varying hot water use patterns; and 5) operating cost savings under different electricity prices and hot water use. The paper presents the results of a life-cycle cost analysis of the adoption of HPWHs in a representative sample of American homes, as well as national impact analysis for different market share scenarios. Assuming equipment costs that would result from high production volume, the results show that HPWHs can be cost effective in all regions for most single family homes, especially when the water heater is not installed in a conditioned space. HPWHs are not cost effective for most manufactured home and multi-family installations, due to lower average hot water use and the water heater in the majority of cases being installed in conditioned space, where cooling of the indoor environment and size and air flow requirements of HPWHs increase installation costs.

  14. Heater head for stirling engine

    Science.gov (United States)

    Corey, John A.

    1985-07-09

    A monolithic heater head assembly which augments cast fins with ceramic inserts which narrow the flow of combustion gas and obtains high thermal effectiveness with the assembly including an improved flange design which gives greater durability and reduced conduction loss.

  15. ENERGY STAR Certified Water Heaters

    Data.gov (United States)

    U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 3.0 ENERGY STAR Program Requirements for Water Heaters that are effective April 16, 2015....

  16. Thermomechanics of the granular bed T-joint water heater

    Science.gov (United States)

    Teplitskii, Yu. S.; Belonovich, D. G.

    2012-11-01

    On the basis of the heat transfer model taking into account the radiative transport the temperature distribution and the resistance of the water heater with a granular packing having two independent air inlets have been investigated. The generalized dependence for calculating the resistance of the granular bed has been obtained.

  17. Comparative Study and Design of Solar Water Heater

    Directory of Open Access Journals (Sweden)

    K.Sainath,Y.krishna, Mohd Salahuddin, Mohammed Siddique Ahmed, Md Ismail, Syed Rahman,Mohammed Noman, Mohd Khaleel Ullah, Faraz Ur Rehman Azhar, Mohd Moizuddin,Mohd Riyaz Uddin.

    2014-10-01

    Full Text Available A solar water heater design is made from the plastic bottles of thumps up & plastic pipe(p.v.c run up by the centre of each solar heater in a row of bottles, these bottles act as glazing & hold reflectors made from the black paint. Solar water heaters are made of two basic parts: a solar collector that gathers radiant energy and a storage tank for the hot water inside. These systems are used to heat water for swimming pools, as well as for domestic cooking and cleaning needs. A system in which the sun’s heat is gathered by a solar collector and used to increase the temperature of a heat-transfer fluid , which flows through the pipes in the collector; the heat contained in this fluid then is conveyed and transferred to the water to be heated. Solar water heaters use the solar energy from the sun to generate heat (not electricity which can then be used to heat water for showering, space heating, industrial processes or even solar cooling. However, the research shows that the electric water spends about the 25% of its home energy costs on heating water. If we make a water heater without the collector then we can save a lot of money solar water heater do not polluted if one investing on SWH avoids carbon dioxide nitrogen oxide and sulphur dioxide and the other air pollution wastes and the utility generates power on your bum fuel to heat your household water when SWH replaces the an electric water heater. This electric displaced over 20 years replaced more than 50 tones avoided c02 emissions alone co2 traps heat in the upper most atmosphere thus, contributing to the ‘Green House Effect

  18. Our Environment in Hot Water: Comparing Water Heaters, A Life Cycle Approach Comparing Tank and Tankless Water Heaters in California

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Alison; McMahon, James; Masanet, Eric; Lutz, Jim

    2008-08-13

    Residential water heating is a large source of energy use in California homes. This project took a life cycle approach to comparing tank and tankless water heaters in Northern and Southern California. Information about the life cycle phases was calculated using the European Union's Methodology study for EcoDesign of Energy-using Products (MEEUP) and the National Renewable Energy Laboratory's Life Cycle Inventory (NREL LCI) database. In a unit-to-unit comparison, it was found that tankless water heaters would lessen impacts of water heating by reducing annual energy use by 2800 MJ/year (16% compared to tank), and reducing global warming emissions by 175 kg CO2 eqv./year (18% reduction). Overall, the production and combustion of natural gas in the use phase had the largest impact. Total waste, VOCs, PAHs, particulate matter, and heavy-metals-to-air categories were also affected relatively strongly by manufacturing processes. It was estimated that tankless water heater users would have to use 10 more gallons of hot water a day (an increased usage of approximately 20%) to have the same impact as tank water heaters. The project results suggest that if a higher percentage of Californians used tankless water heaters, environmental impacts caused by water heating would be smaller.

  19. Quench Heater Studies for the LHC Magnets

    CERN Document Server

    Rodríguez-Mateos, F

    2001-01-01

    About 2000 LHC (CERN's Large Hadron Collider) superconducting magnets will be protected with quench heaters against development of excessive voltage and overheating after a resistive transition. The quench heater strips are powered by capacitor bank discharge power supplies. The strips are made of stainless steel partially plated with copper to reduce their resistance and to allow for the connection of quench heaters in series. The strips are embedded in between two polyimide foils. The initial power density and the current decay time determine the quench heater effectiveness. Since only one type of heater power supply will be available, the copper plating cycle is adapted for the various magnet types to keep the resistance of the heater circuit constant. Different quench heater designs have been tested on various prototype magnets to optimise the copper-plating cycle and the electric insulation of the heater strip. This paper summarises the experimental results and computations that allowed to finalise the h...

  20. Shared savings gets realtor new water heaters

    Energy Technology Data Exchange (ETDEWEB)

    Mullin, R.

    1983-08-08

    The Grenadier Realty Co. of New York is financing four energy-efficient water heaters for apartment buildings with a shared savings arrangement. The arrangement allows Grenadier to avoid front-end costs, which were paid by Independent Water Heaters Inc. in exchange for a decreasing share of the savings. Grenadier will own the heaters when the five-year contract expires. By allowing a shutdown of boilers during the summer months, the heaters will further increase energy savings. (DCK)

  1. A Novel Radiative Substrate Heater

    OpenAIRE

    CEYLAN, Abdullah; Kaynak, Erdal; ÖZCAN, Şadan; Firat, Tezer

    2004-01-01

    In this work, we have developed a new low cost radiative substrate heater for deposition of high-Tc superconducting thin films. It has all the features required for the preparation of high quality superconducting thin films. It is possible to reach ~ 800 °C substrate temperature with it by using only one 250 W halogen projector bulb.

  2. Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Sparn, B.; Hudon, K.; Christensen, D.

    2014-06-01

    This paper explores the laboratory performance of five integrated Heat Pump Water Heaters (HPWHs) across a wide range of operating conditions representative of US climate regions. HPWHs are expected to provide significant energy savings in certain climate zones when compared to typical electric resistance water heaters. Results show that this technology is a viable option in most climates, but differences in control schemes and design features impact the performance of the units tested. Tests were conducted to map heat pump performance across the operating range and to determine the logic used to control the heat pump and the backup electric heaters. Other tests performed include two unique draw profile tests, reduced air flow performance tests and the standard DOE rating tests. The results from all these tests are presented here for all five units tested. The results of these tests will be used to improve the EnergyPlus heat pump water heater for use in BEopt(tm) whole-house building simulations.

  3. Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Sparn, B.; Hudon, K.; Christensen, D.

    2014-06-01

    This paper explores the laboratory performance of five integrated Heat Pump Water Heaters (HPWHs) across a wide range of operating conditions representative of U.S. climate regions. HPWHs are expected to provide significant energy savings in certain climate zones when compared to typical electric resistance water heaters. Results show that this technology is a viable option in most climates, but differences in control schemes and design features impact the performance of the units tested. Tests were conducted to map heat pump performance across the operating range and to determine the logic used to control the heat pump and the backup electric heaters. Other tests performed include two unique draw profile tests, reduced air flow performance tests and the standard DOE rating tests. The results from all these tests are presented here for all five units tested. The results of these tests will be used to improve the EnergyPlus heat pump water heater for use in BEopt™ whole-house building simulations.

  4. Biogas Digester with Simple Solar Heater

    Directory of Open Access Journals (Sweden)

    Kh S Karimov

    2012-10-01

    persamaan tenaga seimbang untuk jisim statik cecair yang dipanaskan; parameter penebat haba tangki metana telah dikira. Pencerna biogas terdiri dari tangki metana yang dilengkapkan dengan penyerap pemanas beralik untuk menggunakan tenaga solar bagi memanaskan sluri yang disediakan dari bahan buangan organik yang berbeza (najis, sampah, sisa makanan,etc. Tangki metana telah diisi sehingga 70% isipadu buangan oraganik dari institut GIK, pertamanya adalah sampah dan keduanya adalah najis lembu. Pencerna telah dikaji bagi tempoh tiga bulan (Oktober-Disember, 2009 dan dua bulan (Februari-Mac, 2010. Kejadian radiasi solar terhadap penyerap, suhu sluri dan suhu ambien telah diukur. Didapati suhu penahanan adalah empat minggu dan dua minggu masing-masing dengan menggunakan sampah sahaja dan sampah dengan najis lembu, dan kuantiti biogas dihasilkan adalah masing-masing 0.4 m3 and 8.0 m3. Sebagai tambahan, skema peningkatan biogas untuk peranjakan karbon dioksida, hidrogen sulfida dan wap air dari biogas dan penukaran tenaga biogas kepada tenaga elektrik juga dibincangkan.KEYWORDS:  solar biogas; digester; methane tank; reverse absorber; built-in heater; solar energy

  5. Welding shield for coupling heaters

    Science.gov (United States)

    Menotti, James Louis

    2010-03-09

    Systems for coupling end portions of two elongated heater portions and methods of using such systems to treat a subsurface formation are described herein. A system may include a holding system configured to hold end portions of the two elongated heater portions so that the end portions are abutted together or located near each other; a shield for enclosing the end portions, and one or more inert gas inlets configured to provide at least one inert gas to flush the system with inert gas during welding of the end portions. The shield may be configured to inhibit oxidation during welding that joins the end portions together. The shield may include a hinged door that, when closed, is configured to at least partially isolate the interior of the shield from the atmosphere. The hinged door, when open, is configured to allow access to the interior of the shield.

  6. Experimental characteristics of vortex heaters

    Science.gov (United States)

    Piralishvili, Sh. A.; Novikov, N. N.

    The performance of a Ranque-Hilsch vortex tube is investigated experimentally for the case where the tube operates as a heater, with the mass of the heated gas remaining constant. The results obtained indicate that energy separation zones with sufficiently high (50 percent) relative heating effects can be achieved for a gas flow ratio of unity. A nomogram is presented for calculating the relative and absolute heating effects as a function of the tube geometry.

  7. Graphite/Epoxy Deicing Heater

    Science.gov (United States)

    Hung, Ching-Cheh; Dillehay, Michael E.; Stahl, Mark

    1988-01-01

    Heat applied close to surface protected. One ply of highly electrically- and thermally-conductive brominated-graphite fiber composite laminated between two plies of electrically-insulating composite material, with michel foil making contact with end portions of graphite fibers. Part of foil exposed beyond composite to serve as electrical contact. Graphite/Epoxy composite heater developed to prevent and reverse formation of ice on advanced composite surfaces of aircraft.

  8. Near-surface heater experiments

    Energy Technology Data Exchange (ETDEWEB)

    Tyler, L.D.; Cuderman, J.F.; Krumhansl, J.L.; Lappin, A.

    1978-12-31

    Full-scale near-surface heater experiments are presently being conducted by Sandia Laboratories in the Conasauga Formation at Oak Ridge, Tennessee, and in the Eleana Formation on the Nevada Test Site, Nevada. The purposes of these experiments are: (1) to determine if argillaceous media can withstand thermal loads characteristic of high level waste; (2) to provide data for improvement of themomechanical modeling of argillaceous rocks; (3) to identify instrumentation development needed for further in situ testing; and (4) to identify unexpected general types of behavior, if any. The basic instrumentation of these tests consists of a heater in a central hole, surrounded by arrays of holes containing various instrumentation. Temperatures, thermal profiles, vertical displacements, volatile pressurization, and changes in in situ stresses are measured in each experiment as a function of time, and compared with pretest modeling results. Results to date, though in general agreement with modeling results assuming conductive heat transfer within the rock, indicate that the presence of even small amounts of water can drastically affect heat transfer within the heater hole itself, and that small amounts of upward convection of water may be occurring in the higher temperature areas of the Conasauga experiments.

  9. Thermal response of transparent silver nanowire/PEDOT:PSS film heaters.

    Science.gov (United States)

    Ji, Shulin; He, Weiwei; Wang, Ke; Ran, Yunxia; Ye, Changhui

    2014-12-10

    Thermal response behavior of transparent silver nanowire/PEDOT:PSS film heaters are intensively studied for manipulating heating temperature, response time, and power consumption. Influences of substrate heat capacity, heat transfer coefficient between air and heater, sheet resistance and dimension of Ag nanowire film, on the thermal response are investigated from thermodynamic analysis. Suggestion is given for practical applications that if other parameters are fixed, Ag nanowire coverage can be utilized as an effective parameter to adjust the thermal response. The heat transfer coefficient plays opposite roles on thermal response speed and achievable steady temperature. A value of ≈32 W m(-2) K(-1) is obtained from transient process analysis after correcting it by considering heater resistance variation during heating tests. Guidance of designing heaters with a given response time is provided by forming Ag nanowire film with a suitable sheet resistance on substrate of appropriate material and a certain thickness. Thermal response tests of designed Ag heaters are performed to show higher heating temperature, shorter response time, and lower power consumption (179 °C cm(2) W(-1)) than ITO/FTO heaters, as well as homogeneous temperature distribution and stability for repeated use. Potential applications of the Ag heaters in window defogging, sensing and thermochromism are manifested.

  10. Parallel heater system for subsurface formations

    Energy Technology Data Exchange (ETDEWEB)

    Harris, Christopher Kelvin (Houston, TX); Karanikas, John Michael (Houston, TX); Nguyen, Scott Vinh (Houston, TX)

    2011-10-25

    A heating system for a subsurface formation is disclosed. The system includes a plurality of substantially horizontally oriented or inclined heater sections located in a hydrocarbon containing layer in the formation. At least a portion of two of the heater sections are substantially parallel to each other. The ends of at least two of the heater sections in the layer are electrically coupled to a substantially horizontal, or inclined, electrical conductor oriented substantially perpendicular to the ends of the at least two heater sections.

  11. SINGLE HEATER TEST FINAL REPORT

    Energy Technology Data Exchange (ETDEWEB)

    J.B. Cho

    1999-05-01

    The Single Heater Test is the first of the in-situ thermal tests conducted by the U.S. Department of Energy as part of its program of characterizing Yucca Mountain in Nevada as the potential site for a proposed deep geologic repository for the disposal of spent nuclear fuel and high-level nuclear waste. The Site Characterization Plan (DOE 1988) contained an extensive plan of in-situ thermal tests aimed at understanding specific aspects of the response of the local rock-mass around the potential repository to the heat from the radioactive decay of the emplaced waste. With the refocusing of the Site Characterization Plan by the ''Civilian Radioactive Waste Management Program Plan'' (DOE 1994), a consolidated thermal testing program emerged by 1995 as documented in the reports ''In-Situ Thermal Testing Program Strategy'' (DOE 1995) and ''Updated In-Situ Thermal Testing Program Strategy'' (CRWMS M&O 1997a). The concept of the Single Heater Test took shape in the summer of 1995 and detailed planning and design of the test started with the beginning fiscal year 1996. The overall objective of the Single Heater Test was to gain an understanding of the coupled thermal, mechanical, hydrological, and chemical processes that are anticipated to occur in the local rock-mass in the potential repository as a result of heat from radioactive decay of the emplaced waste. This included making a priori predictions of the test results using existing models and subsequently refining or modifying the models, on the basis of comparative and interpretive analyses of the measurements and predictions. A second, no less important, objective was to try out, in a full-scale field setting, the various instruments and equipment to be employed in the future on a much larger, more complex, thermal test of longer duration, such as the Drift Scale Test. This ''shake down'' or trial aspect of the Single Heater Test applied

  12. Strategy Guideline. Proper Water Heater Selection

    Energy Technology Data Exchange (ETDEWEB)

    Hoeschele, M. [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); Springer, D. [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); German, A. [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); Staller, J. [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); Zhang, Y. [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States)

    2015-04-09

    This Strategy Guideline on proper water heater selection was developed by the Building America team Alliance for Residential Building Innovation to provide step-by-step procedures for evaluating preferred cost-effective options for energy efficient water heater alternatives based on local utility rates, climate, and anticipated loads.

  13. Strategy Guideline: Proper Water Heater Selection

    Energy Technology Data Exchange (ETDEWEB)

    Hoeschele, M. [Alliance for Residential Building Innovation, Davis, CA (United States); Springer, D. [Alliance for Residential Building Innovation, Davis, CA (United States); German, A. [Alliance for Residential Building Innovation, Davis, CA (United States); Staller, J. [Alliance for Residential Building Innovation, Davis, CA (United States); Zhang, Y. [Alliance for Residential Building Innovation, Davis, CA (United States)

    2015-04-01

    This Strategy Guideline on proper water heater selection was developed by the Building America team Alliance for Residential Building Innovation to provide step-by-step procedures for evaluating preferred cost-effective options for energy efficient water heater alternatives based on local utility rates, climate, and anticipated loads.

  14. Subsurface connection methods for subsurface heaters

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar, Harold J. (Bellaire, TX); Bass, Ronald Marshall (Houston, TX); Kim, Dong Sub (Sugar Land, TX); Mason, Stanley Leroy (Allen, TX); Stegemeier, George Leo (Houston, TX); Keltner, Thomas Joseph (Spring, TX); Carl, Jr., Frederick Gordon (Houston, TX)

    2010-12-28

    A system for heating a subsurface formation is described. The system includes a first elongated heater in a first opening in the formation. The first elongated heater includes an exposed metal section in a portion of the first opening. The portion is below a layer of the formation to be heated. The exposed metal section is exposed to the formation. A second elongated heater is in a second opening in the formation. The second opening connects to the first opening at or near the portion of the first opening below the layer to be heated. At least a portion of an exposed metal section of the second elongated heater is electrically coupled to at least a portion of the exposed metal section of the first elongated heater in the portion of the first opening below the layer to be heated.

  15. Effects of heated seat and foot heater on thermal comfort and heater energy consumption in vehicle.

    Science.gov (United States)

    Oi, Hajime; Yanagi, Kotaro; Tabata, Koji; Tochihara, Yutaka

    2011-08-01

    Subjective experiments involving 12 different conditions were conducted to investigate the effects of heated seats and foot heaters in vehicles on thermal sensation and thermal comfort. The experimental conditions involved various combinations of the operative temperature in the test room (10 or 20°C), a heated seat (on/off) and a foot heater (room operative temperature +10 or +20°C). The heated seat and foot heater improved the occupant's thermal sensation and comfort in cool environments. The room operative temperature at which the occupants felt a 'neutral' overall thermal sensation was decreased by about 3°C by using the heated seat or foot heater and by about 6°C when both devices were used. Moreover, the effects of these devices on vehicle heater energy consumption were investigated using simulations. As a result, it was revealed that heated seats and foot heaters can reduce the total heater energy consumption of vehicles. Statement of Relevance: Subjective experiments were conducted to investigate the effects of heated seats and foot heaters in vehicles on thermal comfort. The heated seat and foot heater improved the occupant's thermal sensation and comfort in cool environments. These devices can reduce the total heater energy consumption in vehicles.

  16. Biogas Digester with Simple Solar Heater

    OpenAIRE

    Kh S Karimov; Muhammad Abid

    2012-01-01

    ABSTRACT: In this research work, the design, fabrication and investigation of a biogas digester with simple solar heater are presented. For the solar heater, a built-in reverse absorber type heater was used. The maximum temperature (50°C) inside the methane tank was taken as a main parameter for the design of the digester. Then, the energy balance equation for the case of a static mass of fluid being heated was used to model the process. The parameters of thermal insulation of the methane tan...

  17. 46 CFR 52.25-15 - Fired thermal fluid heaters.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Fired thermal fluid heaters. 52.25-15 Section 52.25-15... Boiler Types § 52.25-15 Fired thermal fluid heaters. (a) Fired thermal fluid heaters shall be designed...) Each fired thermal fluid heater must be fitted with a control which prevents the heat transfer...

  18. 40 CFR 65.149 - Boilers and process heaters.

    Science.gov (United States)

    2010-07-01

    ... thermal units per hour) or greater. (ii) A boiler or process heater into which the vent stream is... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Boilers and process heaters. 65.149... System or a Process § 65.149 Boilers and process heaters. (a) Boiler and process heater equipment...

  19. 46 CFR 63.25-5 - Fired thermal fluid heaters.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Fired thermal fluid heaters. 63.25-5 Section 63.25-5... heaters. (a) Construction. Fired thermal fluid heaters must meet the requirements of part 52 of this chapter, as applicable. (b) Controls. Fired thermal fluid heaters must have a low fluid level...

  20. Varying properties along lengths of temperature limited heaters

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar, Harold J. (Bellaire, TX); Xie, Xueying (Houston, TX); Miller, David Scott (Katy, TX); Ginestra, Jean Charles (Richmond, TX)

    2011-07-26

    A system for heating a subsurface formation is described. The system includes an elongated heater in an opening in the formation. The elongated heater includes two or more portions along the length of the heater that have different power outputs. At least one portion of the elongated heater includes at least one temperature limited portion with at least one selected temperature at which the portion provides a reduced heat output. The heater is configured to provide heat to the formation with the different power outputs. The heater is configured so that the heater heats one or more portions of the formation at one or more selected heating rates.

  1. Experimental studies of operating characteristics of a downhole electric heater

    Energy Technology Data Exchange (ETDEWEB)

    Simkin, E.M.; Sergeev, A.I.; Sheinman, A.B.

    1967-06-01

    A new type of electric downhole heater for deparaffinization and heating of formations in oil wells is described. The heater is a hollow hermetic cylinder, which contains an electrode insulated from the body of the heater. The cylinder contains a predetemined volume of water of fixed electrical resistance. Resistance of this water is adjusted by addition of salt. A cable supplying the electrode with electric current also ground the heater by body. The current passes through the water, heats it, and produces steam. The steam heats up the hermetically sealed body of the heater, and heat flows to the well fluid around the heater. A schematic diagram of the heater is shown. Thermal output of the heater depends on current supplied, dimension of heater and components, resistance and volume of water in heater, and other parameters. All these factors are correlated with heat output by a series of graphs and equations.

  2. Slat Heater Boxes for Thermal Vacuum Testing

    Science.gov (United States)

    Ungar, Eugene

    2003-01-01

    Slat heater boxes have been invented for controlling the sink temperatures of objects under test in a thermal vacuum chamber, the walls of which are cooled to the temperature of liquid nitrogen. A slat heater box (see Figure 1) includes a framework of struts that support electrically heated slats that are coated with a high-emissivity optically gray paint. The slats can be grouped together into heater zones for the purpose of maintaining an even temperature within each side. The sink temperature of an object under test is defined as the steady-state temperature of the object in the vacuum/ radiative environment during the absence of any internal heat source or sink. The slat heater box makes it possible to closely control the radiation environment to obtain a desired sink temperature. The slat heater box is placed inside the cold thermal vacuum chamber, and the object under test is placed inside (but not in contact with) the slat heater box. The slat heaters occupy about a third of the field of view from any point on the surface of the object under test, the remainder of the field of view being occupied by the cold chamber wall. Thus, the radiation environment is established by the combined effects of the slat heater box and the cold chamber wall. Given (1) the temperature of the chamber wall, (2) the fractions of the field of view occupied by the chamber wall and the slat heater box, and (3) the emissivities of the slats, chamber wall, and the surface of object under test, the slat temperature required to maintain a desired sink temperature can be calculated by solving the equations of gray-body radiation for the steady-state adiabatic case (equal absorption and emission by the object under test). Slat heater boxes offer an important advantage over the infrared lamps that have been previously used to obtain desired sink temperatures: In comparison with an infrared lamp, a slat heater box provides a greater degree of sink temperature uniformity for a test

  3. Note: Improved wire-wound heater.

    Science.gov (United States)

    Steinmann, Ricardo G; Vitoux, Hugo

    2015-01-01

    The authors have measured, at cryogenic temperature, the upper limit of the heat transfer in different configurations of a wire-wound heater. We found that the heat transferred has an upper limit of about 15 W/cm(2) and is dependent on the diameter of the wire. In this paper, we present three ways of increasing the heat transferred by this type of heater and its application in different continuous flow cryostats.

  4. Note: Improved wire-wound heater

    Science.gov (United States)

    Steinmann, Ricardo G.; Vitoux, Hugo

    2015-01-01

    The authors have measured, at cryogenic temperature, the upper limit of the heat transfer in different configurations of a wire-wound heater. We found that the heat transferred has an upper limit of about 15 W/cm2 and is dependent on the diameter of the wire. In this paper, we present three ways of increasing the heat transferred by this type of heater and its application in different continuous flow cryostats.

  5. Diesel particulate filter with zoned resistive heater

    Science.gov (United States)

    Gonze, Eugene V [Pinckney, MI

    2011-03-08

    A diesel particulate filter assembly comprises a diesel particulate filter (DPF) and a heater assembly. The DPF filters a particulate from exhaust produced by an engine. The heater assembly has a first metallic layer that is applied to the DPF, a resistive layer that is applied to the first metallic layer, and a second metallic layer that is applied to the resistive layer. The second metallic layer is etched to form a plurality of zones.

  6. STUDY ON THE OPTIMIZATION OF IGBT THERMAL MANAGEMENT FOR PTC HEATER

    Directory of Open Access Journals (Sweden)

    J. W. JEONG

    2015-12-01

    Full Text Available It is essential to optimize HVAC (Heating, Ventilation and Air-Conditioning system for a thermal plant or an electric vehicle since it has a significant effect on the thermal efficiency. PTC (positive temperature coefficient heaters are often used for a heating system and the power module of the PTC heaters, IGBT (insulated gate bipolar mode transistor, requires thermal management. In this study, in order to maximize the cooling performance for IGBT, a novel method that uses forced convection inside the HVAC duct with heat sinks was developed. In addition, heat sinks were optimized in terms of IGBT junction temperature and heat sink weight by 3-dimensional CFD (Computational Fluid Dynamics simulation. The results show that the junction temperature of IGBT for 5.6kW PTC heater can be maintained at about 335K.

  7. The effects of operating conditions on emissions from masonry heaters and sauna stoves

    Energy Technology Data Exchange (ETDEWEB)

    Tissari, Jarkko; Hytoenen, Kati; Sippula, Olli [Fine Particle and Aerosol Technology Laboratory, University of Kuopio, PO Box 1627, 70211 Kuopio (Finland); Jokiniemi, Jorma [Fine Particle and Aerosol Technology Laboratory, University of Kuopio, PO Box 1627, 70211 Kuopio (Finland)]|[VTT, Technical Research Centre of Finland, Fine Particles, PO Box 1000, 02044 VTT, Espoo (Finland)

    2009-03-15

    Emissions from masonry heaters and sauna stoves were studied. In the sauna stove the production of organic gaseous carbon (OGC) at 10 gC kg{sup -1} (per kilogram of fuel), carbon monoxide (CO) at 55 g kg{sup -1}, fine particle mass (PM{sub 1}) at 5 g kg{sup -1} and number emissions (N) at 1.8 x 10{sup 15} kg{sup -1} was higher than in other measured appliances. In a modern technology masonry heater with a unique grate, the emissions were very low: 0.4 gC kg{sup -1} OGC, 14 g kg{sup -1} CO and 0.7 g kg{sup -1} PM{sub 1}. Conventional masonry heaters, using small logs, clearly produced higher emissions when compared to using large logs. Doubling the fuel load caused emission factors to increase by up to 4- times (OGC), except for the number emission, which decreased from 4.0 x 10{sup 14} to 2.0 x 10{sup 14} kg{sup -1}. From the conventional masonry heater 90% of the PM was emitted during the firing phase. Its combustion process is different to that in stoves or conventional open fireplaces. The insufficient supply of air, due to too fast pyrolysis, and increased ash release, due to the high combustion temperature, are the main parameters which cause high particle and gas emissions in masonry heaters and sauna stoves. (author)

  8. Dielectric Heaters for Testing Spacecraft Nuclear Reactors

    Science.gov (United States)

    Sims, William Herbert; Bitteker, Leo; Godfroy, Thomas

    2006-01-01

    A document proposes the development of radio-frequency-(RF)-driven dielectric heaters for non-nuclear thermal testing of the cores of nuclear-fission reactors for spacecraft. Like the electrical-resistance heaters used heretofore for such testing, the dielectric heaters would be inserted in the reactors in place of nuclear fuel rods. A typical heater according to the proposal would consist of a rod of lossy dielectric material sized and shaped like a fuel rod and containing an electrically conductive rod along its center line. Exploiting the dielectric loss mechanism that is usually considered a nuisance in other applications, an RF signal, typically at a frequency .50 MHz and an amplitude between 2 and 5 kV, would be applied to the central conductor to heat the dielectric material. The main advantage of the proposal is that the wiring needed for the RF dielectric heating would be simpler and easier to fabricate than is the wiring needed for resistance heating. In some applications, it might be possible to eliminate all heater wiring and, instead, beam the RF heating power into the dielectric rods from external antennas.

  9. Primary helium heater for propellant pressurization systems

    Science.gov (United States)

    Reichmuth, D. M.; Nguyen, T. V.; Pieper, J. L.

    1991-01-01

    The primary helium heater is a unique design that provides direct heating of pressurant gas for large pressure fed propulsion systems. It has been conceptually designed to supply a heated (800-1000 R) pressurization gas to both a liquid oxygen and an RP-1 propellant tank. This pressurization gas is generated within the heater by mixing super critical helium (40-300 R and 3000-1600 psi) with an appropriate amount of combustion products from a 4:1 throttling stoichiometric LO2/LH2 combustor. This simple, low cost and reliable mixer utilizes the large quantity of helium to provide stoichiometric combustor cooling, extend the throttling limits and enhance the combustion stability margin. Preliminary combustion, thermal, and CFD analyses confirm that this low-pressure-drop direct helium heater can provide the constant-temperature pressurant suitable for tank pressurization of both fuel and oxidizer tanks of large pressure fed vehicles.

  10. Economic analysis of residential solar water heaters

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-09-23

    A typical residential solar water heater, and typical cost and performance information are described briefly. The monthly costs and savings of the typical system are discussed. Economic evaluations of solar water heaters are presented in increasingly complex levels of detail. Utilizing a typical system, the effective interest rate that the purchaser of a system would receive on money invested is shown for all regions of the country. The importance of numerous variables that can make a significant difference on the economics of the system is described. Methods for calculating the Payback Period for any non-typical solar water heater are described. This calculated Payback Period is then shown to be related to the effective interest rate that the puchaser of the system would receive for a typical set of economic conditions. A method is presented to calculate the effective interest rate that the solar system would provide. (MHR)

  11. Measure Guideline. Transitioning to a Tankless Water Heater

    Energy Technology Data Exchange (ETDEWEB)

    Brozyna, K. [IBACOS, Inc., Pittsburgh, PA (United States); Rapport, A. [IBACOS, Inc., Pittsburgh, PA (United States)

    2012-09-01

    This measure guideline provides information to help residential builders and retrofitters with the design, specification, selection, implementation, installation, and maintenance issues of transitioning from tank-type water heaters to tankless water heaters.

  12. Anti-freezing performance research of dry type shell-tube heat exchanger for air source heat pump water chiller-heater unit%空气源热泵冷(热)水机组用干式壳管换热器防冻性能研究

    Institute of Scientific and Technical Information of China (English)

    张龙爱; 陈忠杰; 王传华

    2012-01-01

    针对空气源热泵冷(热)水机组运行中可能出现的干式壳管换热器冻裂问题,分析其被冻裂的主要因素,并且对壳管换热器冻裂的关键因素——蒸发压力过低的原因进行分析.基于分析结果,对壳管换热器的设计进行改进,同时对低流量保护点进行试验验证.%Aiming at the frost-cracking problem of the dry type shell-tube heat exchanger for air source heat pump water chiller-heater unit, the main influencing factors are analyzed. The key reason of shell-tube heat exchanger frost-cracking is analyzed that is too low evaporating pressure. The design of shell-tube heat exchanger is improved based on the analysis results, and the limited flow rate for protection of flow switch is verified by the test.

  13. Heater size effect on subcooled pool boiling of FC-72

    Energy Technology Data Exchange (ETDEWEB)

    Raj, Rishi; Kim, Jungho [University of Maryland, College Park, MD (United States). Dept. of Mechanical Engineering

    2009-07-01

    Extensive research has been conducted on pool boiling using heaters larger than the capillary length. For large heaters and/or high gravity conditions, boiling is dominated by buoyancy, and the heat transfer is heater size independent. Much less is known about boiling on small heaters and at low gravity levels. The ratio of heater size L{sub h} to capillary length L{sub c} is an important parameter in the determination of heater size dependence on heat transfer. As the ratio L{sub h}/L{sub c} decreases due to a decrease in either heater size or gravity, surface tension forces become dominant. It is proposed that transition from buoyancy to surface tension dominated boiling occurs when the heater size and bubble departure diameter are of the same order. Previous work in variable gravity with flat surfaces has shown that the heat transfer was heater size independent only when the ratio L{sub h}/L{sub c} was considerably larger than 1. An array of 96 platinum resistance heater elements in a 10 x 10 configuration with individual elements 0.7 x 0.7 mm{sup 2} in size was used to vary heater size and measure the heat transfer. The threshold value of L{sub h}/L{sub c} above which pool boiling is heater size independent was found to be about 2.8. (author)

  14. 46 CFR 111.70-5 - Heater circuits.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Heater circuits. 111.70-5 Section 111.70-5 Shipping... REQUIREMENTS Motor Circuits, Controllers, and Protection § 111.70-5 Heater circuits. (a) If an enclosure for a... from a separate circuit, the heater circuit must be disconnected from its source of potential by...

  15. Water loss from the skin of term and preterm infants nursed under a radiant heater.

    Science.gov (United States)

    Kjartansson, S; Arsan, S; Hammarlund, K; Sjörs, G; Sedin, G

    1995-02-01

    The rate of evaporation from the skin (g/m2/h) was measured in 12 full-term and 16 preterm infants (gestational age 25-34 wk) both during incubator care and when nursed under a radiant heater. The method for evaporation rate measurement is noninvasive and based on determination of the water vapor pressure gradient close to the skin surface. Measurements were first made with the infant nursed in an incubator with a controlled environment with respect to humidity, temperature, and air velocity. The measurements in the term infants were performed at an ambient relative humidity (RH) of 50%, and in the preterm infants first at 50% and subsequently at 30-40%. Evaporation rate was then measured with the infant nursed under a radiant heater. In term infants, mean evaporation rate was 3.3 g/m2/h during incubator care (RH 50%) and 4.4 g/m2/h during care under the radiant heater. In preterm infants, the corresponding values were 15.5 g/m2/h in the incubator at RH 50%, 16.7 g/m2/h at RH 30-40%, and 17.9 g/m2/h under the radiant heater. It is concluded that the evaporative water loss from the skin depends on the ambient water vapor pressure, irrespective of whether the infant is nursed in an incubator or under a radiant heater. The higher rate of evaporation during care under a radiant heater is due to the lower ambient water vapor pressure and not to any direct effect of the nonionizing radiation on the skin.

  16. MATHEMATICAL AND INFORMATION SUPPORT FOR CALCULATION AND DESIGN OF TUBE GAS HEATERS LOCATED IN STRUCTURES

    Directory of Open Access Journals (Sweden)

    CHORNOMORETS H. Y.

    2016-02-01

    Full Text Available Raising of problem. For the design and construction of tube gas heaters in building structures to need solve the problems of analysis and synthesis of such heating system. The mathematical model of this system is consists of: mathematical model of the tube gas heater, mathematical model of heat distribution in the building structure and corresponding boundary conditions. To solve the tasks of analysis and synthesis must be appropriate mathematical and information support. Purpose. The purpose of this paper is to describe the developed mathematical and information support that solve the problems of analysis and synthesis of heating systems with gas tube heaters, located in building constructions.Conclusion. Mathematical support includes the development of algorithms and software for the numerical solution of problems analysis and synthesis heating system. Information support includes all the necessary parameters characterizing the thermal properties of materials which used in the heating system, and the parameters characterizing the heat exchange between the coolant and components of the heating system. It was developed algorithms for solving problems of analysis and synthesis heating system with tube gas heater located in structures to use evolutionary search algorithm and software. It was made experimental study and was obtained results allow to calculate the heat transfer from the gas-air mixture to the boundary surface of the building structure. This results and computation will provide full information support for solving problems of analysis and synthesis of the heating system. Was developed mathematical and software support, which allows to solve the problems of analysis and synthesis heating systems with gas tube heaters, located in building structures. Tube gas heaters located in the building structures allows with small capital expenditures to provide space heating. Is necessary to solve the problems of analysis (calculation and

  17. Solar Air Collectors: How Much Can You Save?

    Science.gov (United States)

    Newburn, J. D.

    1985-04-01

    A collector efficiency curve is used to determine the output of solar air collectors based on the testing of seven solar collectors sold in Iowa. In this application the solar heater is being used as a space heater for a house. The performance of the solar air heater was analyzed and an 8% savings in energy was achieved over a one year period using two 4 x 8 collectors in a typical house.

  18. Analysis of using air-source heat pump water chiller-heater units in the cold regions%空气源热泵冷热水机组在寒冷地区应用的分析

    Institute of Scientific and Technical Information of China (English)

    马最良; 杨自强; 姚杨; 喻银平

    2001-01-01

    针对空气源热泵冷热水机组在寒冷地区冬季使用时结霜、热效率低等问题,提出一种双级热泵系统,即由空气源热泵冷热水机组提供10~20 ℃温水,作为水源热泵的低位热源,组成水源热泵供热系统。分析了这种系统的技术经济性,认为该系统是可行的,具有节能和环保意义。%imed at solving frosting and low heating efficiency of heat pumps in cold regions, puts forward a twin heat pumps heating system that consists of an air source heat pump and a water source heat pump. The air source heat pump supplies 10-20 ℃ water as low grade heat source of the water source heat pump. Analyses the technical and economical features of the system. Considers that the system is practicable and has energy conservation and environment protection effects.

  19. 空气源热泵在学生公寓的热水改造工程中的应用%Application of Air Source Heat Pump Water Heater to Reconstruction Project of Domestic Hot Water in Student Apartment

    Institute of Scientific and Technical Information of China (English)

    何绪春

    2012-01-01

    The domestic water-heating system with gas-fired boiler of a college apartment in Chongqing was discussed.The reconstruction plans concerning air-source heat pump heating system and solar assisted air-source heat system were processed and discussed respectively after the analysis on daily hot water load.Compared with the original water-heating system,the annual operating costs of solar heating systems would be the lowest.%以重庆某学校采用燃气锅炉房作为热源的洗浴热水加热系统作为研究对象。对热水系统日用热量进行了分析。对原加热系统提出两种改造方案:空气源热泵加热系统、太阳能辅助空气源加热系统,探讨了这两种加热系统的系统流程,与原加热系统的年运行费用进行了比较,太阳能加热系统的年运行费用最低。

  20. Analysis Approach to Improve Star Rating Of Water Heater

    Directory of Open Access Journals (Sweden)

    Sujata Dabhade

    2014-07-01

    Full Text Available Electric Water Heaters are widely used all over the world that can be categorized in two types i.e. Instant Water Heaters & Storage type Water Heaters. The energy consumption for 6 liter water heaters is much higher in the storage type of water heater. As energy is an important factor for economic development of country, therefore there is need to save the energy which implies the focus to use Storage type Water Heaters. In 6 Liter water heater, Existing model converting from 4 star rating to 5 star rating by thermal analysis & insulation. After the theoretical calculation of thickness of glass wool is the practical testing of product with BEE norms & got results for 5 Star Calculation. Finally we are doing the thermal analysis for theoretical & practical verification of the product

  1. Development of High Efficiency Carbon Dioxide Commercial Heat Pump Water Heater

    Energy Technology Data Exchange (ETDEWEB)

    Michael PETERSEN; Chad D. BOWERS; Stefan ELBEL; Pega HRNJAK

    2012-07-01

    Although heat pump water heaters are today widely accepted in both Japan and Europe, where energy costs are high and government incentives for their use exist, acceptance of such products in the US has been limited. While this trend is slowly changing with the introduction of heat pump water heaters into the residential market, but acceptance remains low in the commercial sector. The objective of the presented work is the development of a high efficiency R744 heat pump water heater for commercial applications with effective utilization of the cooling capability for air conditioning and/or refrigeration. The ultimate goal is to achieve total system COP of up to 8. This unit will be targeted at commercial use where some cooling load is typically needed year round, such as restaurants, hotels, nursing homes, and hospitals. This paper presents the performance results from the development of four R744 commercial heat pump water heater packages of approximately 35 kW and comparison to a commercially available baseline R134a unit of the same capacity and footprint. In addition, the influences of an internal heat exchanger and an enhanced evaporator on the system performance are described and recommendations are made for further improvements of the R744 system.

  2. Single-heater test final report

    Energy Technology Data Exchange (ETDEWEB)

    Blair, S. C.; Buscheck, T. A.; DeLoach, L. D.; Lin, W.; Ramirez, A. I.

    1998-09-01

    The Single-Heater Test (SHT) was one phase of the field-scale thermal testing program of the Yucca Mountain Site Characterization Project. The primary purpose of the SHT was to study the thermomechanical (TM) behavior of the densely welded, non-lithophysal Topopah Spring tuff at the Exploratory Studies Facility. The SHT was also used as a shake-down for testing thermal-hydrologic-chemical-mechanical processes in situ, testing that will be conducted in the Drift-Scale Test. In the SHT, a line-heat source 5-m long was emplaced in a pillar and used to heat the pillar for approximately nine months. The thermal field was relatively cylindrical about the line-heat source. The heater was turned off after nine months of heating, and the rock mass was monitored during the cool-down for another nine months, until May 28, 1997, when the test was terminated.

  3. AWSWAH - the heat pipe solar water heater

    Energy Technology Data Exchange (ETDEWEB)

    Akyurt, M.

    1986-01-01

    An all weather heat pipe solar water heater (AWSWAH) comprising a collector of 4 m/sup 2/ (43 ft/sup 2/) and a low profile water tank of 160 liters (42 gal.) was developed. A single heat pipe consisting of 30 risers and two manifolds in the evaporator and a spiral condenser was incorporated into the AWSWAH. Condensate metering was done by synthetic fiber wicks. The AWSWAH was tested alongside two conventional solar water heaters of identical dimensions, an open loop system and a closed loop system. It was found that the AWSWAH was an average of 50% more effective than the open system in the temperature range 30-90 /sup 0/C (86-194 /sup 0/F). The closed loop system was the least efficient of the three systems.

  4. Improving the Gas Instantaneous Water Heaters Performances

    Directory of Open Access Journals (Sweden)

    Nasir Kloub

    2005-01-01

    Full Text Available This study presents a study of a theoretical and practical investigation of the gas Instantaneous (Tankless water Heaters performance. The results allow us to obtain realistic values of the control system in the various capacities gaseous flowing water heaters. The objective of this work is to study the operation of the plans in the field of controlling and checking low capacity gaseous flowing water in order to choose the proper plan of the logical values and measures for these equipments that may be used in industrial conditions. Also results of the work proved to be accurate. A design of the control system was made. The results of the practical experiment of the control system were similar to the arithmetic results.

  5. Water heaters subject to new regulations.

    Science.gov (United States)

    Clarke, Alan

    2014-06-01

    On 26 September 2015 the Ecodesign and Energy Labelling Directives for water heaters (Lot 2) come into force, meaning that water-heating products sold in the UK and other countries in the European Economic Area will need to meet minimum energy performance criteria in order to be legally placed on the market, and will require an energy label. Here Alan Clarke, technical support manager at Heatrae Sadia, explains more.

  6. Field Monitoring Protocol: Heat Pump Water Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Sparn, B.; Earle, L.; Christensen, D.; Maguire, J.; Wilson, E.; Hancock, E.

    2013-02-01

    This document provides a standard field monitoring protocol for evaluating the installed performance of Heat Pump Water Heaters in residential buildings. The report is organized to be consistent with the chronology of field test planning and execution. Research questions are identified first, followed by a discussion of analysis methods, and then the details of measuring the required information are laid out. A field validation of the protocol at a house near the NREL campus is included for reference.

  7. Field Monitoring Protocol. Heat Pump Water Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Sparn, B. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Earle, L. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Christensen, D. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Maguire, J. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Wilson, E. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Hancock, C. E. [Mountain Energy Partnership, Longmont, CO (United States)

    2013-02-01

    This document provides a standard field monitoring protocol for evaluating the installed performance of Heat Pump Water Heaters in residential buildings. The report is organized to be consistent with the chronology of field test planning and execution. Research questions are identified first, followed by a discussion of analysis methods, and then the details of measuring the required information are laid out. A field validation of the protocol at a house near the NREL campus is included for reference.

  8. Large-scale floor heater creating a comfortable space; Kaitekina kukan wo sozosuru daikibo yukadanbo

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-10-01

    Floor heater radiates at a low temperature from under, warming people from the feet upward and filling the chamber with warm air mildly and uniformly. Keeping one`s head cool and one`s feet warm is the key to one`s health, goes a Japanese adage. Not only residences but also school houses, welfare facilities, hospitals, retail shops, and offices have come to accept high-capability floor heating equipment. For Musashino Municipal Sakai Nursery School where infants play barefoot, a floor heater is the best choice. A floor heat creates an environment safe and healthy, ensuring sound sleep. It does not cause dust to rise because it does not produce air currents in the room, and does not pollute air or make noise because the heat source is installed outdoors. Tsunekiyo-no-Sato, which is a facility for senior citizens in general, serves chiefly as a special nursing home for the aged, and therefore is requested to be comfortable, safe, and clean. For the old people whose body temperature adjusting system has degraded in function, floor heaters are the best for warming because it does not involve abrupt temperature changes. The Hokkaido Branch of Asahi Breweries, Ltd., employs a floor warming system for its wine house to ensure proper storage, and the ambient temperature in winter is kept at 3degC or higher

  9. 40 CFR Table 4 to Subpart Ddddd of... - Operating Limits for Boilers and Process Heaters With Hydrogen Chloride Emission Limits

    Science.gov (United States)

    2010-07-01

    ... compliance with the applicable emission limit for hydrogen chloride. 2. Dry scrubber control Maintain the... Process Heaters With Hydrogen Chloride Emission Limits 4 Table 4 to Subpart DDDDD of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION...

  10. Solar-Powered Cooler and Heater for an Automobile Interior

    Science.gov (United States)

    Howard, Richard T.

    2006-01-01

    The apparatus would include a solar photovoltaic panel mounted on the roof and a panellike assembly mounted in a window opening. The window-mounted assembly would include a stack of thermoelectric devices sandwiched between two heat sinks. A fan would circulate interior air over one heat sink. Another fan would circulate exterior air over the other heat sink. The fans and the thermoelectric devices would be powered by the solar photovoltaic panel. By means of a double-pole, double-throw switch, the panel voltage fed to the thermoelectric stack would be set to the desired polarity: For cooling operation, the chosen polarity would be one in which the thermoelectric devices transport heat from the inside heat sink to the outside one; for heating operation, the opposite polarity would be chosen. Because thermoelectric devices are more efficient in heating than in cooling, this apparatus would be more effective as a heater than as a cooler. However, if the apparatus were to include means to circulate air between the outside and the inside without opening the windows, then its effectiveness as a cooler in a hot, sunny location would be increased.

  11. Solair heater program: solair applications study. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1977-12-01

    General Electric has designed and tested a low-cost solar system using a vacuum tube solar air heater under ERDA Contract E(11-1)-2705. This contract extension has been provided to evaluate various applications of this solar collector. The evaluation identified attractive applications, evaluated corresponding control procedures, estimated system performance, compared economically insolation and insulation, and evaluated the repackaging of off-the-shelf equipment for improved cost effectiveness. The results of this study prompted General Electric's marketing group to do a detailed commercialization study of a residential domestic water heating system using the Solair concept which has been selected as the most attractive application. Other attractive applications are space/domestic water heating and a heat pump assisted solar system/domestic water heating where the heat pump and the solar system function in parallel. A prime advantage of heated air solar systems over liquid systems is cost and longer life which results in higher BTU's/dollar. Other air system advantages are no liquid leakage problems, no toxicity of freezing problems, and less complicated equipment. A hybrid solar system has been identified that can improve the market penetration of solar energy. This system would use the existing mass of the house for energy storage thereby reducing solar cost and complexity. Adequate performance can be obtained with house temperature swings comparable to those used in nighttime setback of the thermostat. Details of this system are provided.

  12. Laboratory Evaluation of Gas-Fired Tankless and Storage Water Heater Approaches to Combination Water and Space Heating

    Energy Technology Data Exchange (ETDEWEB)

    Kingston, T. [Gas Technology Inst., Des Plaines, IL (United States); Scott, S. [Gas Technology Inst., Des Plaines, IL (United States)

    2013-03-01

    Homebuilders are exploring more cost-effective combined space and water heating systems (combo systems) with major water heater manufacturers that are offering pre-engineered forced air space heating combo systems. In this project, unlike standardized tests, laboratory tests were conducted that subjected condensing tankless and storage water heater based combo systems to realistic, coincidental space and domestic hot water loads and found that the tankless combo system maintained more stable DHW and space heating temperatures than the storage combo system, among other key findings.

  13. Insulated conductor temperature limited heater for subsurface heating coupled in a three-phase WYE configuration

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar, Harold J. (Bellaire, TX); Sandberg, Chester Ledlie (Palo Alto, CA)

    2010-11-09

    A heating system for a subsurface formation is described. The heating system includes a first heater, a second heater, and a third heater placed in an opening in the subsurface formation. Each heater includes: an electrical conductor; an insulation layer at least partially surrounding the electrical conductor; and an electrically conductive sheath at least partially surrounding the insulation layer. The electrical conductor is electrically coupled to the sheath at a lower end portion of the heater. The lower end portion is the portion of the heater distal from a surface of the opening. The first heater, the second heater, and the third heater are electrically coupled at the lower end portions of the heaters. The first heater, the second heater, and the third heater are configured to be electrically coupled in a three-phase wye configuration.

  14. Research and development of a high efficiency gas-fired water heater. Volume 2. Task reports

    Energy Technology Data Exchange (ETDEWEB)

    Vasilakis, A.D.; Pearson, J.F.; Gerstmann, J.

    1980-01-01

    Design and development of a cost-effective high efficiency gas-fired water heater to attain a service efficiency of 70% (including the effect of exfiltration) and a service efficiency of 78% (excluding exfiltration) for a 75 GPD draw at a 90/sup 0/F temperature rise, with a stored water to conditioned air temperature difference of 80/sup 0/F, are described in detail. Based on concept evaluation, a non-powered natural draft water heater was chosen as the most cost-effective design to develop. The projected installed cost is $374 compared to $200 for a conventional unit. When the project water heater is compared to a conventional unit, it has a payback of 3.7 years and life cycle savings of $350 to the consumer. A prototype water heater was designed, constructed, and tested. When operated with sealed combustion, the unit has a service efficiency of 66.4% (including the effect of exfiltration) below a burner input of 32,000 Btu/h. In the open combustion configuration, the unit operated at a measured efficiency of 66.4% Btu/h (excluding exfiltration). This compares with a service efficiency of 51.3% for a conventional water heater and 61% for a conventional high efficiency unit capable of meeting ASHRAE 90-75. Operational tests showed the unit performed well with no evidence of stacking or hot spots. It met or exceeded all capacity or usage tests specified in the program test plan and met all emission goals. Future work will concentrate on designing, building, and testing pre-production units. It is anticipated that both sealed combustion and open draft models will be pursued.

  15. Field Performance of Heat Pump Water Heaters in the Northeast

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, Carl [Consortium for Advanced Residential Buildings, Norwalk, CT (United States); Puttagunta, Srikanth [Consortium for Advanced Residential Buildings, Norwalk, CT (United States)

    2016-02-01

    Heat pump water heaters (HPWHs) are finally entering the mainstream residential water heater market. Potential catalysts are increased consumer demand for higher energy efficiency electric water heating and a new Federal water heating standard that effectively mandates use of HPWHs for electric storage water heaters with nominal capacities greater than 55 gallons. When compared to electric resistance water heating, the energy and cost savings potential of HPWHs is tremendous. Converting all electric resistance water heaters to HPWHs could save American consumers 7.8 billion dollars annually ($182 per household) in water heating operating costs and cut annual residential source energy consumption for water heating by 0.70 quads.

  16. Measure Guideline: Transitioning to a Tankless Water Heater

    Energy Technology Data Exchange (ETDEWEB)

    Brozyna, K.; Rapport, A.

    2012-09-01

    This Measure Guideline provides information to help residential builders and retrofitters with the design, specification, selection, implementation, installation, and maintenance issues of transitioning from tank-type water heaters to tankless water heaters. The report compares the differences between tankless and tank-type water heaters, highlighting the energy savings that can be realized by adopting tankless water heaters over tank-type water heaters. Selection criteria and risks discussed include unit sizing and location, water distribution system, plumbing line length and diameter, water quality, electrical backup, and code issues. Cost and performance data are provided for various types of tankless and tank-type water heaters, both natural gas fired and electric. Also considered are interactions between the tankless water heater and other functional elements of a house, such as cold water supply and low-flow devices. Operating costs and energy use of water distribution systems for single- and two-story houses are provided, along with discussion of the various types of distribution systems that can be used with tankless water heaters. Finally, details to prepare for proper installation of a tankless water heater are described.

  17. Heat Pump Water Heater Ducting Strategies with Encapsulated Attics in Climate Zones 2 and 4

    Energy Technology Data Exchange (ETDEWEB)

    Sweet, M. L. [Southface Energy Inst., Atlanta, GA (United States); Francisco, A. [Southface Energy Inst., Atlanta, GA (United States); Roberts, S. G. [Southface Energy Inst., Atlanta, GA (United States)

    2016-05-01

    The focus of this study is on the performance of HPWHs with several different duct configurations and their effects on whole building heating, cooling, and moisture loads. A.O. Smith 60 gallon Voltex (PHPT-60) heat pump water heaters (HPWHs) were included at two project sites and ducted to or located within spray foamed encapsulated attics. The effect of ducting a HPWH's air stream does not diminish its efficiency if the ducting does not reduce intake air temperature, which expands HPWH application to confined areas.

  18. Fast nanotopography imaging using a high speed cantilever with integrated heater-thermometer.

    Science.gov (United States)

    Lee, Byeonghee; Somnath, Suhas; King, William P

    2013-04-05

    This paper presents a high speed tapping cantilever with an integrated heater-thermometer for fast nanotopography imaging. The cantilever is much smaller and faster than previous heated cantilevers, with a length of 35 μm and a resonant frequency of 1.4 MHz. The mechanical response time is characterized by scanning over a backward-facing step of height 20 nm. The mechanical response time is 77 μs in air and 448 μs in water, which compares favorably to the fastest commercial cantilevers that do not have integrated heaters. The doped silicon cantilever is designed with an integrated heater that can heat and cool in about 10 μs and can operate in both air and water. We demonstrate standard laser-based topography imaging along with thermal topography imaging, when the cantilever is actuated via the piezoelectric shaker in an atomic force microscope system and when it is actuated by Lorentz forces. The cantilever can perform thermal topography imaging in tapping mode with an imaging resolution of 7 nm at a scan speed of 1.46 mm s(-1).

  19. The Industrial Design of Water Heater

    Institute of Scientific and Technical Information of China (English)

    张萌萌

    2014-01-01

    The design was inspired by the understanding to the fine life understanding of life, relaxed requirement and under-standing of fashion. Each link of easy life present in the water heater design. The principle of"artappliances, life"brand phi-losophy, refined and understated elegance is the core essence, is also the brand logo. In the"draw the fine life inspiration, the core brand design language create eternal artistic quality", every product tothe interpretation of home life art trend, to embody the elegant life style annotation and experience, committed to the urban elites to create exquisitelife style.

  20. Static Characteristics of Absorption Chiller-Heater Supplying Cold and Hot Water Simultaneously

    Science.gov (United States)

    Inoue, Naoyuki; Irie, Tomoyoshi

    Absorption chiller-heaters which can supply both chilled water and hot water at the same time, are used for cooling and heating air conditioning systems. In this paper, we classified absorption cold and hot water generating cycles and control methods, studied these absorption cycles by cycle simulation. In economizer cycle, condensed refrigerant which heats hot water is transported to cooling cycle and used effectively for cooling chilled water, Concerning with transported condensed refrigerant, there are two methods, all condensed refrigerant or required refrigerant for cooling are transported to cooling cycle, and required refrigerant method is better for energy saving. Adding improvement of solution control to this economizer cycle, simultaneous cold and hot water supplying chiller-heaters have good characteristics of energy saving in the all region.

  1. Evaluation of radiofrequency dielectric heaters workers exposure.

    Science.gov (United States)

    Benes, M; Del Frate, S; Villalta, R

    2008-01-01

    Radiofrequency dielectric heaters (RFDH) are widely used in the woodworking industry for gluing laminates by applying pressure and RF heating. The workers operating such equipment remain in the vicinity of the machinery all day and can therefore be exposed to considerable levels of electric and magnetic field at RFs. This work describes the method used to measure the strength of fields generated by this particular machinery. This procedure is based on current methods cited in the literature and introduces the necessary modifications to meet this specific case. In particular, as there is often a scarcity of technical data available relating to such heaters, it is suggested that a spectrum analyser be used for measurements in the frequencies domain. On the basis of the data obtained the norms of reference are established, the instrumentation to be used in successive stages determined as well as the identification of possible sources of interference from spurious signals. Furthermore, a mapping of the field strengths is presented and the means of determining the decay curve as a function of distance. This last type of measurement is done to estimate the effectiveness of grounding the machinery. The report ends with an estimate of the exposure of workers to electromagnetic fields and also some recommendations for reducing risk.

  2. 46 CFR 111.85-1 - Electric oil immersion heaters.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Electric oil immersion heaters. 111.85-1 Section 111.85-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Electric Oil Immersion Heaters § 111.85-1 Electric oil immersion...

  3. Parametric excitation of whistler waves by HF heater

    Science.gov (United States)

    Kuo, S. P.; Lee, M. C.

    1989-01-01

    Possible generation of whistler waves by Tromso HF heater is investigated. It is shown that the HF heater wave can parametrically decay into a whistler wave and a Langmuir wave. Since whistler waves may have a broad range of frequency, the simultaneously excited Langmuir waves can have a much broader frequency bandwidth than those excited by the parametric decay instability.

  4. Infrared transparent graphene heater for silicon photonic integrated circuits.

    Science.gov (United States)

    Schall, Daniel; Mohsin, Muhammad; Sagade, Abhay A; Otto, Martin; Chmielak, Bartos; Suckow, Stephan; Giesecke, Anna Lena; Neumaier, Daniel; Kurz, Heinrich

    2016-04-18

    Thermo-optical tuning of the refractive index is one of the pivotal operations performed in integrated silicon photonic circuits for thermal stabilization, compensation of fabrication tolerances, and implementation of photonic operations. Currently, heaters based on metal wires provide the temperature control in the silicon waveguide. The strong interaction of metal and light, however, necessitates a certain gap between the heater and the photonic structure to avoid significant transmission loss. Here we present a graphene heater that overcomes this constraint and enables an energy efficient tuning of the refractive index. We achieve a tuning power as low as 22 mW per free spectral range and fast response time of 3 µs, outperforming metal based waveguide heaters. Simulations support the experimental results and suggest that for graphene heaters the spacing to the silicon can be further reduced yielding the best possible energy efficiency and operation speed.

  5. Effect of Fuel Wobbe Number on Pollutant Emissions from Advanced Technology Residential Water Heaters: Results of Controlled Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Rapp, Vi H.; Singer, Brett C.

    2014-03-01

    The research summarized in this report is part of a larger effort to evaluate the potential air quality impacts of using liquefied natural gas in California. A difference of potential importance between many liquefied natural gas blends and the natural gas blends that have been distributed in California in recent years is the higher Wobbe number of liquefied natural gas. Wobbe number is a measure of the energy delivery rate for appliances that use orifice- or pressure-based fuel metering. The effect of Wobbe number on pollutant emissions from residential water heaters was evaluated in controlled experiments. Experiments were conducted on eight storage water heaters, including five with “ultra low-NO{sub X}” burners, and four on-demand (tankless) water heaters, all of which featured ultra low-NO{sub X} burners. Pollutant emissions were quantified as air-free concentrations in the appliance flue and fuel-based emission factors in units of nanogram of pollutant emitter per joule of fuel energy consumed. Emissions were measured for carbon monoxide (CO), nitrogen oxides (NO{sub X}), nitrogen oxide (NO), formaldehyde and acetaldehyde as the water heaters were operated through defined operating cycles using fuels with varying Wobbe number. The reference fuel was Northern California line gas with Wobbe number ranging from 1344 to 1365. Test fuels had Wobbe numbers of 1360, 1390 and 1420. The most prominent finding was an increase in NO{sub X} emissions with increasing Wobbe number: all five of the ultra low-NO{sub X} storage water heaters and two of the four ultra low-NO{sub X} on-demand water heaters had statistically discernible (p<0.10) increases in NO{sub X} with fuel Wobbe number. The largest percentage increases occurred for the ultra low-NO{sub X} water heaters. There was a discernible change in CO emissions with Wobbe number for all four of the on-demand devices tested. The on-demand water heater with the highest CO emissions also had the largest CO increase

  6. Fluid bed solids heater. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Preuit, L. C.

    1980-01-01

    A solids heater which operates at up to 2000 F was designed, fabricated, installed and operated through checkout at the Morgantown Energy Technology Center at Morgantown, West Virginia. The system, designated the 2000 F Fluid Bed Solids Heater (FBSH) uses a fluidized bed to heat limestone to 600 F and aluminium oxide or silicon carbide to 2000 F and discharges heated solids upon demand. The FBSH with added valve handling and pressurization equipment is known as the Valve Hot Solids Test Unit and is intended for use by the US Department of Energy for testing of valves for severe service applications in coal conversion and utilization processes. The FBSH as designed and supplied by Combustion Power Company includes process equipment, controls, the enclosing building and other associated equipment. In the 600 F range of operation it can circulate limestone through two valve test trains simultaneously on a continuous basis. Only one valve test train is used for 2000 F solids and operation in that range is also continuous. Limestone, crushed to minus 5/16 size, is heated, discharged, and recycled at a maximum average rate of 250 lb/min while aluminum oxide or silicon carbide, No. 8 grit, is circulated at rates up to 167 lb/min. The FBSH control system is designed for automatic operation, and capability is included for external computerized data acquisition and/or supervisory control. An operating and maintenance manual and as-built drawings have been submitted. This report describes the FBSH equipment, its design basis, and its operation. It has been prepared and submitted in fulfillment of Contract Number DIAC05-77ET10499.

  7. Measure Guideline: Heat Pump Water Heaters in New and Existing Homes

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, C.; Puttagunta, S.; Owens, D.

    2012-02-01

    This Building America Measure Guideline is intended for builders, contractors, homeowners, and policy-makers. This document is intended to explore the issues surrounding heat pump water heaters (HPWHs) to ensure that homeowners and contractors have the tools needed to appropriately and efficiently install HPWHs. Heat pump water heaters (HPWHs) promise to significantly reduce energy consumption for domestic hot water (DHW) over standard electric resistance water heaters (ERWHs). While ERWHs perform with energy factors (EFs) around 0.9, new HPWHs boast EFs upwards of 2.0. High energy factors in HPWHs are achieved by combining a vapor compression system, which extracts heat from the surrounding air at high efficiencies, with electric resistance element(s), which are better suited to meet large hot water demands. Swapping ERWHs with HPWHs could result in roughly 50% reduction in water heating energy consumption for 35.6% of all U.S. households. This Building America Measure Guideline is intended for builders, contractors, homeowners, and policy-makers. While HPWHs promise to significantly reduce energy use for DHW, proper installation, selection, and maintenance of HPWHs is required to ensure high operating efficiency and reliability. This document is intended to explore the issues surrounding HPWHs to ensure that homeowners and contractors have the tools needed to appropriately and efficiently install HPWHs. Section 1 of this guideline provides a brief description of HPWHs and their operation. Section 2 highlights the cost and energy savings of HPWHs as well as the variables that affect HPWH performance, reliability, and efficiency. Section 3 gives guidelines for proper installation and maintenance of HPWHs, selection criteria for locating HPWHs, and highlights of important differences between ERWH and HPWH installations. Throughout this document, CARB has included results from the evaluation of 14 heat pump water heaters (including three recently released HPWH

  8. Thermal emission of neutron stars with internal heaters

    CERN Document Server

    Kaminker, A D; Potekhin, A Y; Yakovlev, D G

    2014-01-01

    Using 1D and 2D cooling codes we study thermal emission from neutron stars with steady state internal heaters of various intensities and geometries (blobs or spherical layers) located at different depths in the crust. The generated heat tends to propagate radially, from the heater down to the stellar core and up to the surface; it is also emitted by neutrinos. In local regions near the heater the results are well described with the 1D code. The heater's region projects onto the stellar surface forming a hot spot. There are two heat propagation regimes. In the first, conduction outflow regime (realized at heat rates $H_0 \\lesssim 10^{20}$ erg cm$^{-3}$ s$^{-1}$ or temperatures $T_\\mathrm{h} \\lesssim 10^9$ K in the heater) the thermal surface emission of the star depends on the heater's power and neutrino emission in the stellar core. In the second, neutrino outflow regime ($H_0 \\gtrsim 10^{20}$ erg cm$^{-3}$ s$^{-1}$ or $T_\\mathrm{h} \\gtrsim 10^9$ K) the surface thermal emission becomes independent of heater's...

  9. Design and Implementation of the MSL Cruise Propulsion Tank Heaters

    Science.gov (United States)

    Krylo, Robert; Mikhaylov, Rebecca; Cucullu, Gordon; Watkins, Brenda

    2008-01-01

    This slide presentation reviews the design and the implementation of the heaters for the Mars Science Laboratory (MSL). The pressurized tanks store hydrazine that freezes at 2 C, this means that heaters are required to keep the hydrazine and the helium at 36 C for the trip to Mars. Using the TMG software the heat loss was analyzed, and a thermal model simulates a half full tank which yielded a 13W heating requirement for each hemisphere. Views of the design, and the heater are included.

  10. Modeling heat transfer from quench protection heaters to superconducting cables in Nb3Sn magnets

    CERN Document Server

    Salmi, T; Caspi, S; Felice, H; Prestemon, S; Chlachidze, G; Kate, H H J ten

    2013-01-01

    We use a recently developed quench protection heater modeling tool for an analysis of heater delays in superconducting high-field Nb3Sn accelerator magnets. The results suggest that the calculated delays are consistent with experimental data, and show how the heater delay depends on the main heater design parameters.

  11. 75 FR 52892 - Energy Conservation Program for Consumer Products: Test Procedures for Residential Water Heaters...

    Science.gov (United States)

    2010-08-30

    ... discretion, this direct measurement procedure is optional for vented heaters without thermal stack dampers... efficiency is calculated for vented heaters with manual controls and thermal dampers. For all other vented... Procedures for Residential Water Heaters, Direct Heating Equipment, and Pool Heaters AGENCY: Office of...

  12. 78 FR 2340 - Energy Conservation Program: Test Procedures for Residential Water Heaters and Commercial Water...

    Science.gov (United States)

    2013-01-11

    ... also questionable whether thermal efficiency is an appropriate metric for smaller storage water heaters... that the test procedure for residential water heaters utilized the thermal efficiency and standby loss..., particularly for heat pump water heaters and gas instantaneous water heaters. 3. Revised Thermal Efficiency...

  13. 75 FR 20111 - Energy Conservation Program: Energy Conservation Standards for Residential Water Heaters, Direct...

    Science.gov (United States)

    2010-04-16

    ... 46,000 65 Table II.3--Current Federal Energy Conservation Standards for Pool Heaters Thermal efficiency as of Product class January 1, 1990 Gas-Fired Pool Heater Thermal Efficiency = 78% ] 2. History of... Heaters, Direct Heating Equipment, and Pool Heaters; Final Rule #0;#0;Federal Register / Vol. 75, No....

  14. 76 FR 56347 - Energy Conservation Program for Consumer Products: Test Procedures for Residential Water Heaters...

    Science.gov (United States)

    2011-09-13

    ... of the pool heater as: E OUT = BOH Where: BOH = as defined in 5.2 of this appendix E t = thermal... defined in 5.3 of this appendix 5.4.3 Calculate the pool heater integrated thermal efficiency (TE I ) (in... Residential Water Heaters, Direct Heating Equipment, and Pool Heaters (Standby Mode and Off Mode)...

  15. 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.

  16. 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.

  17. Research and development of a heat-pump water heater. Volume 2. R and D task reports

    Energy Technology Data Exchange (ETDEWEB)

    Dunning, R.L.; Amthor, F.R.; Doyle, E.J.

    1978-08-01

    The heat pump water heater is a device that works much like a window air conditioner except that heat from the home is pumped into a water tank rather than to the outdoors. The objective established for the device is to operate with a Coefficient of Performance (COP) of 3 or, an input of one unit of electric energy would create three units of heat energy in the form of hot water. With such a COP, the device would use only one-third the energy and at one-third the cost of a standard resistance water heater. This Volume 2 contains the final reports of the three major tasks performed in Phase I. In Task 2, a market study identifies the future market and selects an initial target market and channel of distribution, all based on an analysis of the parameters affecting feasibility of the device and the factors that will affect its market acceptance. In the Task 3 report, the results of a design and test program to arrive at final designs of heat pumps for both new water heaters and for retrofitting existing water heaters are presented. In the Task 4 report, a plan for an extensive field demonstration involving use in actual homes is presented. Volume 1 contains a final summary report of the information in Volume 2.

  18. Analytical Model for Ring Heater Thermal Compensation in Advanced LIGO

    CERN Document Server

    Ramette, Joshua; Brooks, Aidan; Blair, Carl; Wang, Haoyu; Heintze, Matthew

    2015-01-01

    Advanced laser interferometer gravitational-wave detectors use high laser power to achieve design sensitivity. A small part of this power is absorbed in the interferometer cavity mirrors where it creates thermal lenses, causing aberrations in the main laser beam that must be minimized by the actuation of "ring heaters," additional heater elements that are aimed to reduce the temperature gradients in the mirrors. In this article we derive the first analytical model of the temperature field generated by an ideal ring heater. We express the resulting optical aberration contribution to the main laser beam in this axisymmetric case. Used in conjunction with wavefront measurements, our model provides a more complete understanding of the thermal state of the cavity mirrors and will allow a more efficient use of the ring heaters in Advanced LIGO.

  19. A High Performance Cathode Heater for Hall Thrusters Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The current state-of-the-art co-axial swaged tantalum (Ta) heaters use magnesium oxide (MgO) insulators, which limits their operation to temperatures well below...

  20. New Home Buyer Solar Water Heater Trade-Off Study

    Energy Technology Data Exchange (ETDEWEB)

    Symmetrics Marketing Corporation

    1999-08-18

    This report details the results of a research conducted in 1998 and 1999 and outlines a marketing deployment plan designed for businesses interested in marketing solar water heaters in the new home industry.

  1. Temperature limited heater utilizing non-ferromagnetic conductor

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar,; Harold J. (Bellaire, TX), Harris; Kelvin, Christopher [Houston, TX

    2012-07-17

    A heater is described. The heater includes a ferromagnetic conductor and an electrical conductor electrically coupled to the ferromagnetic conductor. The ferromagnetic conductor is positioned relative to the electrical conductor such that an electromagnetic field produced by time-varying current flow in the ferromagnetic conductor confines a majority of the flow of the electrical current to the electrical conductor at temperatures below or near a selected temperature.

  2. Gravity and Heater Size Effects on Pool Boiling Heat Transfer

    Science.gov (United States)

    Kim, Jungho; Raj, Rishi

    2014-01-01

    The current work is based on observations of boiling heat transfer over a continuous range of gravity levels between 0g to 1.8g and varying heater sizes with a fluorinert as the test liquid (FC-72/n-perfluorohexane). Variable gravity pool boiling heat transfer measurements over a wide range of gravity levels were made during parabolic flight campaigns as well as onboard the International Space Station. For large heaters and-or higher gravity conditions, buoyancy dominated boiling and heat transfer results were heater size independent. The power law coefficient for gravity in the heat transfer equation was found to be a function of wall temperature under these conditions. Under low gravity conditions and-or for smaller heaters, surface tension forces dominated and heat transfer results were heater size dependent. A pool boiling regime map differentiating buoyancy and surface tension dominated regimes was developed along with a unified framework that allowed for scaling of pool boiling over a wide range of gravity levels and heater sizes. The scaling laws developed in this study are expected to allow performance quantification of phase change based technologies under variable gravity environments eventually leading to their implementation in space based applications.

  3. Thermo-Electron Ballistic Coolers or Heaters

    Science.gov (United States)

    Choi, Sang H.

    2003-01-01

    Electronic heat-transfer devices of a proposed type would exploit some of the quantum-wire-like, pseudo-superconducting properties of single-wall carbon nanotubes or, optionally, room-temperature-superconducting polymers (RTSPs). The devices are denoted thermo-electron ballistic (TEB) coolers or heaters because one of the properties that they exploit is the totally or nearly ballistic (dissipation or scattering free) transport of electrons. This property is observed in RTSPs and carbon nanotubes that are free of material and geometric defects, except under conditions in which oscillatory electron motions become coupled with vibrations of the nanotubes. Another relevant property is the high number density of electrons passing through carbon nanotubes -- sufficient to sustain electron current densities as large as 100 MA/square cm. The combination of ballistic motion and large current density should make it possible for TEB devices to operate at low applied potentials while pumping heat at rates several orders of magnitude greater than those of thermoelectric devices. It may also enable them to operate with efficiency close to the Carnot limit. In addition, the proposed TEB devices are expected to operate over a wider temperature range

  4. Adaptive individual-cylinder thermal state control using intake air heating for a GDCI engine

    Energy Technology Data Exchange (ETDEWEB)

    Roth, Gregory T.; Sellnau, Mark C.

    2016-08-09

    A system for a multi-cylinder compression ignition engine includes a plurality of heaters, at least one heater per cylinder, with each heater configured to heat air introduced into a cylinder. Independent control of the heaters is provided on a cylinder-by-cylinder basis. A combustion parameter is determined for combustion in each cylinder of the engine, and control of the heater for that cylinder is based on the value of the combustion parameter for combustion in that cylinder. A method for influencing combustion in a multi-cylinder compression ignition engine, including determining a combustion parameter for combustion taking place in a cylinder of the engine and controlling a heater configured to heat air introduced into that cylinder, is also provided.

  5. Water inflow into boreholes during the Stripa heater experiments

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, P.H.; Rachiele, R.; Remer, J.S.; Carlsson, H.

    1981-04-01

    During the operation of three in-situ heater experiments at Stripa, Sweden, groundwater flowed into many of the instrumentation and heater boreholes. These flows were recovered and measured routinely. The records of water inflow indicate two origins: inflow attributed to local hydrological pressure gradients, and water migration from cracks closing under the rapidly increasing, thermal-induced stress changes. The latter component appeared as a main pulse that occurred when the heaters were turned on, and lasted about 30 to 40 days, steadily declining over the next several months, and decreasing sharply when heater power was decreased or stopped. The magnitude of the total inflow per hole ranged over more than five decades, from 0.1 to over 10,000 liters over the 500 to 600 day time periods. When plotted against the logarithm of total volume, the frequency distribution displays a normal curve dependence with a mean of approximately 10 liters. Of this amount, 1 to 2 liters of flow into 38-mm-diam boreholes accompanied an increase in applied heat load. These amounts are compatible with rock porosities of a fraction of one percent. Inflow into the 3.6 and 5.0 kW heater holes peaked within 3 to 6 days after heater turn on, then declined to zero inflow, with no further inflow measured for the remainder of the experiments. In the heater holes of the time-scaled experiment, which operated at 1.125 kW or less, the initial pulse of inflow took much longer to decay, and 7 of 8 heater holes continued to flow throughout the experiment. The packing off and isolation of a borehole some 40 m distant in the ventilation drift dramatically increased the inflow into the heater holes in one of the three heater experiments. This demonstrated the existence of permeable flow paths among a number of boreholes. The records of water inflow demonstrate the need for a thorough understanding of the nature of fluid flow and storage in fractured crystalline rock.

  6. Performance analysis of air——water dual source heat pump water heater with heat recovery

    Institute of Scientific and Technical Information of China (English)

    CHEN ZeShao; TAO WenQuan; ZHU YanWen; HU Peng

    2012-01-01

    A new air-water dual source heat pump water heater with heat recovery is proposed.The heat pump system can heat water by using a single air source,a single water source,or air-water dual sources.The water is first pre-heated by waste hot water,then heated by the heat pump.Waste heat is recovered by first preheating the cold water and as water source of the heat pump.According to the correlated formulas of the coefficient of performance of air-source heat pump and water-source heat pump,and the gain coefficient of heat recovery-preheater,the formulas for the coefficient of performance of heat pump in six operating modes are obtained by using the dimensionless correspondence analysis method.The system characteristics of heat absorption and release associated with the heat recovery-preheater are analyzed at different working conditions.The developed approaches can provide reference for the optimization of the operating modes and parameters.The results of analysis and experiments show that the coefficient of performance of the device can reach 4-5.5 in winter,twice as much as air source heat pump water heater.The utilization of waste heat in the proposed system is higher than that in the system which only uses waste water to preheating or as heat source.Thus,the effect of energy saving of the new system is obvious.On the other hand,the dimensionless correspondence analysis method is introduced to performance analysis of the heat pump,which also has theoretical significance and practical value.

  7. Combustion-Driven Oscillation in Process Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Seebold, J.G. [Chevron Corporation (Retired), 198 James Avenue, Atherton, CA 94027 (United States)

    2005-10-15

    At this moment in thousands of process heaters all over the world there are, to borrow a phrase from the late Carl Sagan, 'billions and billions' of Btu/hr beneficially being released entirely free of pulsation. On those few occasions, perhaps a dozen and a half in my career, when I would get the inevitable 'Why me?' call, I have generally responsed with something like, 'Consider yourself lucky, you have a rare scientific curiosity on your hands'. Reflecting on the solutions ultimately found, I'm reminded that many years ago my friend Abbott Putnam shared with me an early AGA (American Gas Association) field-service bulletin that included a prescription for eliminating combustion-driven oscillations in home heating units; viz., 'Drill a hole; if that doesn't work, drill another hole' or words to that effect. Many times have I wished that I still had a copy of that bulletin and in this paper we will have occasion, once again, to reflect upon the value of that advice. In this paper we will discuss an instance that arose in a pioneering installation of a breakthrough development of 'extremely', to distinguish it from 'ultra', low-NOx lean premix burner technology. We will illustrate how, when and under what circumstances combustion-driven oscillation can arise; we will touch on the many alternatives for its elimination that were considered and investigated; and we will discuss three practical alternatives for eliminating combustion-driven oscillations.

  8. Multifamily Heat Pump Water Heater Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Hoeschele, M. [Davis Energy Group, Davis, CA (United States). Alliance for Residential Building Innovation; Weitzel, E. [Davis Energy Group, Davis, CA (United States). Alliance for Residential Building Innovation

    2017-03-03

    Although heat pump water heaters (HPWHs) have gained significant attention in recent years as a high efficiency electric water heating solution for single family homes, central HPWHs for commercial or multi-family applications are not as well documented in terms of measured performance and cost effectiveness. To evaluate this technology, the Alliance for Residential Building Innovation team monitored the performance of a 10.5 ton central HPWH installed on a student apartment building at the West Village Zero Net Energy Community in Davis, California. Monitoring data collected over a 16 month period were then used to validate a TRNSYS simulation model. The TRNSYS model was then used to project performance in different climates using local electric rates. Results of the study indicate that after some initial commissioning issues, the HPWH operated reliably with an annual average efficiency of 2.12 (Coefficient of Performance). The observed efficiency was lower than the unit's rated efficiency, primarily due to the fact that the system rarely operated under steady-state conditions. Changes in the system configuration, storage tank sizing, and control settings would likely improve the observed field efficiency. Modeling results suggest significant energy savings relative to electric storage water heating systems (typical annual efficiencies around 0.90) providing for typical simple paybacks of six to ten years without any incentives. The economics versus gas water heating are currently much more challenging given the current low natural gas prices in much of the country. Increased market size for this technology would benefit cost effectiveness and spur greater technology innovation.

  9. Engineering solutions for polymer composites solar water heaters production

    Science.gov (United States)

    Frid, S. E.; Arsatov, A. V.; Oshchepkov, M. Yu.

    2016-06-01

    Analysis of engineering solutions aimed at a considerable decrease of solar water heaters cost via the use of polymer composites in heaters construction and solar collector and heat storage integration into a single device representing an integrated unit results are considered. Possibilities of creating solar water heaters of only three components and changing welding, soldering, mechanical treatment, and assembly of a complicate construction for large components molding of polymer composites and their gluing are demonstrated. Materials of unit components and engineering solutions for their manufacturing are analyzed with consideration for construction requirements of solar water heaters. Optimal materials are fiber glass and carbon-filled plastics based on hot-cure thermosets, and an optimal molding technology is hot molding. It is necessary to manufacture the absorbing panel as corrugated and to use a special paint as its selective coating. Parameters of the unit have been optimized by calculation. Developed two-dimensional numerical model of the unit demonstrates good agreement with the experiment. Optimal ratio of daily load to receiving surface area of a solar water heater operating on a clear summer day in the midland of Russia is 130‒150 L/m2. Storage tank volume and load schedule have a slight effect on solar water heater output. A thermal insulation layer of 35‒40 mm is sufficient to provide an efficient thermal insulation of the back and side walls. An experimental model layout representing a solar water heater prototype of a prime cost of 70‒90/(m2 receiving surface) has been developed for a manufacturing volume of no less than 5000 pieces per year.

  10. Birds heater adaptation and performance using biogas as fuel; Avaliacao do desempenho de um aquecedor para aves adaptado para utilizar biogas como combustivel

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-09-15

    It was carried out a trial to evaluate the adaptation (injector diameter) and performance (biogas consumption and heating efficiency) of a heating adapted to burn biogas. It was tried a common heater, burning liquefied petroleum gas (LPG), operating with low gas pressure (28 cm water column), with calorific capacity of 5024 kJ/h and recommended for 500 birds. The heater was evaluated with the original fuel (LPG) without any modification in the gas injector and after adapting to biogas burning. Five injectors were evaluated with drillings of 1,0053; 1,5080; 1,5708; 1,7672 and 1,980 mm{sup 2}. It also was varied the biogas pressures in the heater entrance of 10, 12, 15, 17 and 20 cm of water column. Results showed that expressions for theoretical calculation and proposed parameters in the literature can be used for aviaries heaters adaptation. The adaptation is simple, indicating the viability for utilization of existing heaters in farms and in the market. Air temperatures were similar to the obtained with the original fuel (LPG). (author)

  11. Structural Benchmark Testing for Stirling Convertor Heater Heads

    Science.gov (United States)

    Krause, David L.; Kalluri, Sreeramesh; Bowman, Randy R.

    2007-01-01

    The National Aeronautics and Space Administration (NASA) has identified high efficiency Stirling technology for potential use on long duration Space Science missions such as Mars rovers, deep space missions, and lunar applications. For the long life times required, a structurally significant design limit for the Stirling convertor heater head is creep deformation induced even under relatively low stress levels at high material temperatures. Conventional investigations of creep behavior adequately rely on experimental results from uniaxial creep specimens, and much creep data is available for the proposed Inconel-718 (IN-718) and MarM-247 nickel-based superalloy materials of construction. However, very little experimental creep information is available that directly applies to the atypical thin walls, the specific microstructures, and the low stress levels. In addition, the geometry and loading conditions apply multiaxial stress states on the heater head components, far from the conditions of uniaxial testing. For these reasons, experimental benchmark testing is underway to aid in accurately assessing the durability of Stirling heater heads. The investigation supplements uniaxial creep testing with pneumatic testing of heater head test articles at elevated temperatures and with stress levels ranging from one to seven times design stresses. This paper presents experimental methods, results, post-test microstructural analyses, and conclusions for both accelerated and non-accelerated tests. The Stirling projects use the results to calibrate deterministic and probabilistic analytical creep models of the heater heads to predict their life times.

  12. Optimal Heater Control with Technology of Fault Tolerance for Compensating Thermoforming Preheating System

    Directory of Open Access Journals (Sweden)

    Zhen-Zhe Li

    2015-01-01

    Full Text Available The adjustment of heater power is very important because the distribution of thickness strongly depends on the distribution of sheet temperature. In this paper, the steady state optimum distribution of heater power is searched by numerical optimization in order to get uniform sheet temperature. In the following step, optimal heater power distribution with a damaged heater was found out using the technology of fault tolerance, which will be used to reduce the repairing time when some heaters are damaged. The merit of this work is that the design variable was the power of each heater which can be directly used in the preheating process of thermoforming.

  13. Development and Validation of a Gas-Fired Residential Heat Pump Water Heater - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Michael Garrabrant; Roger Stout; Paul Glanville; Janice Fitzgerald; Chris Keinath

    2013-01-21

    For gas-fired residential water heating, the U.S. and Canada is predominantly supplied by minimum efficiency storage water heaters with Energy Factors (EF) in the range of 0.59 to 0.62. Higher efficiency and higher cost ($700 - $2,000) options serve about 15% of the market, but still have EFs below 1.0, ranging from 0.65 to 0.95. To develop a new class of water heating products that exceeds the traditional limit of thermal efficiency, the project team designed and demonstrated a packaged water heater driven by a gas-fired ammonia-water absorption heat pump. This gas-fired heat pump water heater can achieve EFs of 1.3 or higher, at a consumer cost of $2,000 or less. Led by Stone Mountain Technologies Inc. (SMTI), with support from A.O. Smith, the Gas Technology Institute (GTI), and Georgia Tech, the cross-functional team completed research and development tasks including cycle modeling, breadboard evaluation of two cycles and two heat exchanger classes, heat pump/storage tank integration, compact solution pump development, combustion system specification, and evaluation of packaged prototype GHPWHs. The heat pump system extracts low grade heat from the ambient air and produces high grade heat suitable for heating water in a storage tank for domestic use. Product features that include conventional installation practices, standard footprint and reasonable economic payback, position the technology to gain significant market penetration, resulting in a large reduction of energy use and greenhouse gas emissions from domestic hot water production.

  14. Impact of Ducting on Heat Pump Water Heater Space Conditioning Energy Use and Comfort

    Energy Technology Data Exchange (ETDEWEB)

    Widder, Sarah H.; Petersen, Joseph M.; Parker, Graham B.; Baechler, Michael C.

    2014-07-21

    Increasing penetration of heat pump water heaters (HPWHs) in the residential sector will offer an important opportunity for energy savings, with a theoretical energy savings of up to 63% per water heater and up to 11% of residential energy use (EIA 2009). However, significant barriers must be overcome before this technology will reach widespread adoption in the Pacific Northwest region and nationwide. One significant barrier noted by the Northwest Energy Efficiency Alliance (NEEA) is the possible interaction with the homes’ space conditioning system for units installed in conditioned spaces. Such complex interactions may decrease the magnitude of whole-house savings available from HPWH installed in the conditioned space in cold climates and could lead to comfort concerns (Larson et al. 2011; Kresta 2012). Modeling studies indicate that the installation location of HPWHs can significantly impact their performance and the resultant whole-house energy savings (Larson et al. 2012; Maguire et al. 2013). However, field data are not currently available to validate these results. This field evaluation of two GE GeoSpring HPWHs in the PNNL Lab Homes is designed to measure the performance and impact on the Lab Home HVAC system of a GE GeoSpring HPWH configured with exhaust ducting compared to an unducted GeoSpring HPWH during heating and cooling season periods; and measure the performance and impact on the Lab Home HVAC system of the GeoSpring HPWH with both supply and exhaust air ducting as compared to an unducted GeoSpring HPWH during heating and cooling season periods. Important metrics evaluated in these experiments include water heater energy use, HVAC energy use, whole house energy use, interior temperatures (as a proxy for thermal comfort), and cost impacts. This technical report presents results from the PNNL Lab Homes experiment.

  15. Development of a cost effective microscope heater stage

    Science.gov (United States)

    Dugre, Joshua; Prayaga, Chandra; Wade, Aaron

    Utilizing 3D printing technology, a heater stage has been developed and implemented for microscopic systems. Due to the flexibility of 3D printing,the heater stage can be easily modified to fit any sample size with only slight modifications to the heating element being required. The sample in contact with the heating element can also easily be secured in a thermal insulator, such as aluminum foil. The thermal gradient of the heater stage has been recorded to be less than 1°C and has been compared to more expensive designs, and the cost effectiveness of the system has been determined. The system has been tested with a sample of the liquid crystal 8CB in order to determine the exact temperatures of the phase transitions of the crystal to verify that the system is applicable to a wide range of experimental physics. UWF Quality Enhancement Plan Award.

  16. Generation of ionospheric ducts by the HAARP HF heater

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, J A; Pradipta, R; Burton, L M; Labno, A; Lee, M C [Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Watkins, B J; Fallen, C [University of Alaska Fairbanks, Fairbanks, AK 99775 (United States); Kuo, S P [New York University, Brooklyn, NY 11201 (United States); Burke, W J [Air Force Research Laboratory, Hanscom AFB, MA 01731 (United States); Mabius, D; See, B Z, E-mail: mclee@mit.edu [Boston University, Boston, MA 02215 (United States)

    2010-12-15

    We report an investigation of ionospheric ducts having the shape of large plasma sheets, generated by vertically transmitted HAARP HF heater waves in several experiments conducted in Gakona, Alaska. Theory predicts that O-mode heater wave-created ionospheric ducts form parallel-plate waveguides within the meridional plane, and those generated by the X-mode heater waves are orthogonal to the meridional plane. Our theoretical prediction is supported by measurements of ionosonde data (namely ionograms), range-time-intensity (RTI) plots of UHF and HF backscatter radars, as well as magnetometer data analyses. When these plasma sheets experienced ExB drifts, they were intercepted by the HAARP UHF radar and seen as slanted stripes in the RTI plots. This striking feature was also observed in our earlier experiments using the Arecibo UHF radar.

  17. Solar-powered hot-air system

    Science.gov (United States)

    1979-01-01

    Solar-powered air heater supplies part or all of space heating requirements of residential or commercial buildings and is interfaced with air to water heat exchanger to heat domestic hot water. System has potential application in drying agricultural products such as cotton, lumber, corn, grains, and peanuts.

  18. Process for thermal imaging scanning of a swaged heater for an anode subassembly of a hollow cathode assembly

    Science.gov (United States)

    Patterson, Michael J. (Inventor); Verhey, Timothy R. R. (Inventor); Soulas, George C. (Inventor)

    2004-01-01

    A process for thermal imaging scanning of a swaged heater of an anode subassembly of a hollow cathode assembly, comprising scanning a swaged heater with a thermal imaging radiometer to measure a temperature distribution of the heater; raising the current in a power supply to increase the temperature of the swaged heater; and measuring the swaged heater temperature using the radiometer, whereupon the temperature distribution along the length of the heater shall be less than plus or minus 5 degrees C.

  19. Lightweight Radioisotope Heater Unit (LWRHU) production for the Cassini mission

    Energy Technology Data Exchange (ETDEWEB)

    Rinehart, G.H.

    1996-06-01

    The Lightweight Radioisotope Heater Unit (LWRHU) is a {sup 238}PuO{sub 2} fueled heat source designed to provide a thermal watt of power for space missions. The LWRHU will be used to maintain the temperature of various components on the spacecraft at the required level. The heat source consists of a {sup 238}PuO{sub 2} fuel pellet, a Pt-30Rh capsule, a pyrolytic graphite insulator, and a woven graphite aeroshell assembly. Los Alamos has fabricated 180 heater units, which will be used on the Cassini mission. This report summarizes the specifications, fabrication processes, and production data for the heat sources fabricated at Los Alamos.

  20. Development of heat pipes for solar water heaters

    Energy Technology Data Exchange (ETDEWEB)

    Akyurt, M.

    1984-01-01

    Numerous heat pipes were designed, manufactured, and filled on a specially developed filling rig. Each heat pipe was incorporated into a prototype solar water heater developed for this purpose, and was tested under actual insolation conditions. An extensive testing program lasting for more than a year revealed that the heat pipes perform satisfactorily as heat transfer elements in solar water heaters. A special heat pipe featuring a compact and effective condenser configuration was also tested. It was observed to likewise exhibit isothermal behavior and hence promised potential for large scale solar applications.

  1. Performance of Thermosyphon Solar Water Heaters in Series

    Directory of Open Access Journals (Sweden)

    Tsong-Sheng Lee

    2012-08-01

    Full Text Available More than a single thermosyphon solar water heater may be employed in applications when considerable hot water consumption is required. In this experimental investigation, eight typical Taiwanese solar water heaters were connected in series. Degree of temperature stratification and thermosyphon flow rate in a horizontal tank were evaluated. The system was tested under no-load, intermittent and continuous load conditions. Results showed that there was stratification in tanks under the no-load condition. Temperature stratification also redeveloped after the draw-off. Analysis of thermal performance of the system was conducted for each condition.

  2. Heater-Integrated Cantilevers for Nano-Samples Thermogravimetric Analysis

    Directory of Open Access Journals (Sweden)

    Valeria Toffoli

    2013-12-01

    Full Text Available The design and characteristics of a micro-system for thermogravimetric analysis (TGA in which heater, temperature sensor and mass sensor are integrated into a single device are presented. The system consists of a suspended cantilever that incorporates a microfabricated resistor, used as both heater and thermometer. A three-dimensional finite element analysis was used to define the structure parameters. TGA sensors were fabricated by standard microlithographic techniques and tested using milli-Q water and polyurethane microcapsule. The results demonstrated that our approach provides a faster and more sensitive TGA with respect to commercial systems.

  3. Thermal injuries caused by ignition of volatile substances by gas water heaters.

    Science.gov (United States)

    Rutan, R L; Desai, M H; Herndon, D N

    1993-01-01

    Based on the cumulative data of this tertiary care facility over the past 25 years, one out of every 70 pediatric patients admitted to our institution sustained their injuries during an explosive event instigated by the ignition of volatile substances from gas water heaters. The majority of injuries related to gas water heaters can be prevented by decreasing the temperature setpoint of the heater, by protecting the heater element itself, and by elevating the water heater to 18 inches above the floor. The first two issues have been adequately addressed; however, gas-fueled water heaters continue to be installed at floor level. Current national guidelines are too rigid and do not adequately address water-heater installation in private residences. Although general prevention campaigns target appropriate storage of volatile substances, they rarely address the explosive potential of gas water heaters in combination with combustible fumes.

  4. Research on Rapid Cooling Technology during Online Maintenance of High-pressure Heater%高压加热器在线检修期间快速冷却技术研究

    Institute of Scientific and Technical Information of China (English)

    李明志; 刘海昌

    2014-01-01

    During units operation, the heater has to be disconnected for online maintenance due to leakage. On the basis of not changing thermal system of high-pressure heater, the compressed air heated by fast cool-ing device is introduced into high-pressure heater. By temperature control of compressed air from outlet of fast cooling device, the heater is cooled fast. The technology can be used to decrease metal temperature of heater in short time and reduce the time of heater cooling and maintenance so that the heater can be resumed soon-er. With the fast cooling technology of heater, temperature of internal metal wall and external wall of heater decreases equally with little differences, which therefore ensures metal property of heater and prevents heater damage due to inappropriate cooling.%机组运行期间,加热器发生泄漏被迫在线解列检修时,在不改变高压加热器热力系统的基础上,将汽轮机快冷装置加热后的压缩空气引入高压加热器,通过控制快冷装置出口压缩空气温度,对加热器进行快速冷却。使用该技术可以在较短时间内降低加热器金属温度,缩短加热器冷却及抢修时间,使加热器可快速恢复使用。由于加热器快冷技术的使用,加热器冷却过程中的金属内外壁温降速度均匀\\温差小,保证加热器金属特性,并避免因加热器冷却不当造成的加热器损坏。

  5. 76 FR 41742 - Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Control of...

    Science.gov (United States)

    2011-07-15

    ... furnaces, outdoor wood-burning appliances, or outdoor hydronic heaters, are free-standing fuel burning... by meeting the EPA air emission standard of 0.6 pound PM per million British thermal unit (Btu) heat... regulating OWBs (also known as outdoor hydronic heaters (OHHs)). The model rule was released in January...

  6. Heat Pump Water Heater Ducting Strategies with Encapsulated Attics in Climate Zones 2 and 4

    Energy Technology Data Exchange (ETDEWEB)

    Sweet, M. L. [Southface Energy Inst., Upper Marlboro, MD (United States); Francisco, A.; Roberts, S. G.

    2016-05-01

    The focus of this study is on the performance of HPWHs with several different duct configurations and their effects on whole building heating, cooling, and moisture loads. A.O. Smith 60 gallon Voltex (PHPT-60) heat pump water heaters (HPWHs) were included at two project sites and ducted to or located within spray foamed encapsulated attics. The effect of ducting a HPWH's air stream does not diminish its efficiency if the ducting does not reduce intake air temperature, which expands HPWH application to confined areas. Exhaust ducts should be insulated to avoid condensation on the exterior, however this imposes a risk of condensation occurring in the duct's interior near the HPWH due to large variation of temperatures between the compressor and the duct and the presence of bulk moisture around the condenser. The HPWH's air conditioning impact on HVAC equipment loads is minimal when the intake and exhaust air streams are connected to a sealed attic and not the living space. A HPWH is not suitable as a replacement dehumidifier in sealed attics as peak moisture loads were observed to only be reduced if the heat pump operated during the morning. It appears that the intake air temperature and humidity was the most dominant variable affecting HPWH performance. Different ducting strategies such as exhaust duct only, intake duct only, and exhaust and intake ducting did not have any effect on HPWH performance.

  7. Savings on natural gas consumption by doubling thermal efficiencies of balanced-flue space heaters

    Energy Technology Data Exchange (ETDEWEB)

    Juanico, Luis E. [Conicet, and Centro Atomico Bariloche e Instituto Balseiro, Av. Bustillo 9500, 8400 Bariloche, Rio Negro (Argentina); Gonzalez, Alejandro D. [Grupo de Estudios Ambientales, Instituto de Investigaciones en Biodiversidad y Medio Ambiente (Inibioma-Conicet), 8400 Bariloche, Rio Negro (Argentina)

    2008-07-01

    Natural gas is a relatively clean fossil fuel for space heating. However, when it is not used efficiently high consumption can become an environmental problem. In Argentina, individual balanced-flue space heaters are the most extensively used in temperate and cold regions. This furnace is a simple device with a burner set into a metal chamber, separated from the indoor ambient by an enclosing cabinet, and both inlet and outgas chimneys are connected to the outdoor ambient. In previous studies, we measured the performance of these commercial devices, and found very low thermal efficiency (in the range of 39-63% depending on the chimney configuration). The extensive use of these devices is possible due to the availability of unlimited amount of subsidised natural gas to households and businesses. In the present work, we developed a prototype with simple and low cost modifications made on commercial models, and measured the improvements on the thermal efficiency. Findings showed better infrared radiation, enhanced indoor air convection, and passive chimney flow regulation leading to thermal efficiency in the range of 75-85%. These values represent an improvement of 100% when compared to marketed models, and hence, the specific cost of the heater per unit of useful heating power delivered was actually reduced. Considering the large market presence of these furnaces in both residential and business sectors in Argentina, the potential benefits related to gas consumption and environmental emissions are very significant. (author)

  8. High-Temperature Compatible Nickel Silicide Thermometer And Heater For Catalytic Chemical Microreactors

    DEFF Research Database (Denmark)

    Jensen, Søren; Quaade, U.J.; Hansen, Ole

    2005-01-01

    Integration of heaters and thermometers is important for agile and accurate control and measurement of the thermal reaction conditions in microfabricated chemical reactors (microreactors). This paper describes development and operation of nickel silicide heaters and temperature sensors...... for temperatures exceeding 700 °C. The heaters and thermometers are integrated with chemical microreactors for heterogeneous catalytic conversion of gasses, and thermally activated catalytic conversion of CO to CO2 in the reactors is demonstrated. The heaters and thermometers are shown to be compatible...

  9. Recovery Act: Water Heater ZigBee Open Standard Wireless Controller

    Energy Technology Data Exchange (ETDEWEB)

    Butler, William P. [Emerson Electric Co., St. Louis, MO (United States); Buescher, Tom [Emerson Electric Co., St. Louis, MO (United States)

    2014-04-30

    The objective of Emerson's Water Heater ZigBee Open Standard Wireless Controller is to support the DOE's AARA priority for Clean, Secure Energy by designing a water heater control that levels out residential and small business peak electricity demand through thermal energy storage in the water heater tank.

  10. 77 FR 74559 - Energy Conservation Program for Consumer Products: Test Procedures for Residential Water Heaters...

    Science.gov (United States)

    2012-12-17

    ... descriptors (i.e., thermal efficiency and pool heater heating seasonal efficiency), as well as seasonal energy... thermal efficiency metric for pool heaters, but did not propose an integrated annual fuel utilization... states that for pool heaters, the descriptor shall be thermal efficiency. (42 U.S.C....

  11. 46 CFR 61.30-5 - Preparation of thermal fluid heater for inspection and test.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Preparation of thermal fluid heater for inspection and... ENGINEERING PERIODIC TESTS AND INSPECTIONS Tests and Inspections of Fired Thermal Fluid Heaters § 61.30-5 Preparation of thermal fluid heater for inspection and test. For visual inspection, access plates and...

  12. 76 FR 63211 - Energy Efficiency Program: Test Procedures for Residential Water Heaters, Direct Heating...

    Science.gov (United States)

    2011-10-12

    ... descriptors (i.e., thermal efficiency and pool heater heating seasonal efficiency), as well as seasonal energy... ``efficiency descriptor,'' EPCA specifies that for pool heaters, the efficiency descriptor shall be ``thermal efficiency.'' (42 U.S.C. 6291(22)(E)) Further, EPCA defines the ``thermal efficiency of pool heaters'' as...

  13. 40 CFR 63.7506 - Do any boilers or process heaters have limited requirements?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 13 2010-07-01 2010-07-01 false Do any boilers or process heaters have limited requirements? 63.7506 Section 63.7506 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... or process heaters have limited requirements? (a) New or reconstructed boilers and process heaters...

  14. Electrothermal pumping with interdigitated electrodes and resistive heaters.

    Science.gov (United States)

    Williams, Stuart J; Green, Nicolas G

    2015-08-01

    Interdigitated electrodes are used in electrokinetic lab-on-a-chip devices for dielectrophoretic trapping and characterization of suspended particles, as well as the production of field-induced fluid flow via AC electroosomosis and electrothermal mechanisms. However, the optimum design for dielectrophoresis, that if symmetrical electrodes, cannot induce bulk electrohydrodynamic pumping. In addition, the mechanism of intrinsic electrothermal pumping is affected by the properties of the fluid, with thermal fields being generated by Joule Heating. This work demonstrates the incorporation of an underlying thin film heater, electrically isolated from the interdigitated electrodes by an insulator layer, to enhance bulk electrothermal pumping. The use of integrated heaters allows the thermal field generation to be controlled independently of the electric field. Numerical simulations are performed to demonstrate the importance of geometrical arrangement of the heater with respect to the interdigitated electrodes, as well as electrode size, spacing, and arrangement. The optimization of such a system is a careful balance between electrokinetics, heat transfer, and fluid dynamics. The heater location and electrode spacing influence the rate of electrothermal pumping significantly more than electrode width and insulator layer thickness. This demonstration will aid in the development of microfluidic electrokinetic systems that want to utilize the advantages associated with electrothermal pumping while simultaneously applying other lab-on-a-chip electrokinetics like dielectrophoresis.

  15. Assessment of a Hybrid Retrofit Gas Water Heater

    Energy Technology Data Exchange (ETDEWEB)

    Hoeschele, Marc [Davis Energy Group, Davis, CA (United States); Weitzel, Elizabeth [Davis Energy Group, Davis, CA (United States); Backman, Christine [Davis Energy Group, Davis, CA (United States)

    2017-02-28

    This project completed a modeling evaluation of a hybrid gas water heater that combines a reduced capacity tankless unit with a downsized storage tank. This product would meet a significant market need by providing a higher efficiency gas water heater solution for retrofit applications while maintaining compatibility with the 1/2 inch gas lines and standard B vents found in most homes. The TRNSYS simulation tool was used to model a base case 0.60 EF atmospheric gas storage water, a 0.82 EF non-condensing gas tankless water heater, an existing (high capacity) hybrid unit on the market, and an alternative hybrid unit with lower storage volume and reduced gas input requirements. Simulations were completed under a 'peak day' sizing scenario with 183 gpd hot water loads in a Minnesota winter climate case. Full-year simulations were then completed in three climates (ranging from Phoenix to Minneapolis) for three hot water load scenarios (36, 57, and 96 gpd). Model projections indicate that the alternative hybrid offers an average 4.5% efficiency improvement relative to the 0.60 EF gas storage unit across all scenarios modeled. The alternative hybrid water heater evaluated does show promise, but the current low cost of natural gas across much of the country and the relatively small incremental efficiency improvement poses challenges in initially building a market demand for the product.

  16. Demand Response Performance of GE Hybrid Heat Pump Water Heater

    Energy Technology Data Exchange (ETDEWEB)

    Widder, Sarah H.; Parker, Graham B.; Petersen, Joseph M.; Baechler, Michael C.

    2013-07-01

    This report describes a project to evaluate and document the DR performance of HPWH as compared to ERWH for two primary types of DR events: peak curtailments and balancing reserves. The experiments were conducted with GE second-generation “Brillion”-enabled GeoSpring hybrid water heaters in the PNNL Lab Homes, with one GE GeoSpring water heater operating in “Standard” electric resistance mode to represent the baseline and one GE GeoSpring water heater operating in “Heat Pump” mode to provide the comparison to heat pump-only demand response. It is expected that “Hybrid” DR performance, which would engage both the heat pump and electric elements, could be interpolated from these two experimental extremes. Signals were sent simultaneously to the two water heaters in the side-by-side PNNL Lab Homes under highly controlled, simulated occupancy conditions. This report presents the results of the evaluation, which documents the demand-response capability of the GE GeoSpring HPWH for peak load reduction and regulation services. The sections describe the experimental protocol and test apparatus used to collect data, present the baselining procedure, discuss the results of the simulated DR events for the HPWH and ERWH, and synthesize key conclusions based on the collected data.

  17. Solar water heaters in China: A new day dawning

    NARCIS (Netherlands)

    Han, Jingyi; Mol, A.P.J.; Lu, Y.

    2010-01-01

    Solar thermal utilization, especially the application of solar water heater technology, has developed rapidly in China in recent decades. Manufacturing and marketing developments have been especially strong in provinces such as Zhejiang, Shandong and Jiangsu. This paper takes Zhejiang, a relatively

  18. Fast thermal nanoimprint lithography by a stamp with integrated heater

    DEFF Research Database (Denmark)

    Tormen, Massimo; Malureanu, Radu; Pedersen, Rasmus Haugstrup

    2008-01-01

    We propose fast nanoimprinting lithography (NIL) process based on the use of stamps with integrated heater. The latter consists of heavily ion implantation n-type doped silicon layer buried below the microstructured surface of the stamp. The stamp is heated by Joule effect, by 50 μs 25 Hz...

  19. Evaluation of the Demand Response Performance of Electric Water Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Mayhorn, Ebony T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Widder, Sarah H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Parker, Steven A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pratt, Richard M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Chassin, Forrest S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-03-17

    The purpose of this project is to verify or refute many of the concerns raised by utilities regarding the ability of large tank HPWHs to perform DR by measuring the performance of HPWHs compared to ERWHs in providing DR services. perform DR by measuring the performance of HPWHs compared to ERWHs in providing DR services. This project was divided into three phases. Phase 1 consisted of week-long laboratory experiments designed to demonstrate technical feasibility of individual large-tank HPWHs in providing DR services compared to large-tank ERWHs. In Phase 2, the individual behaviors of the water heaters were then extrapolated to a population by first calibrating readily available water heater models developed in GridLAB-D simulation software to experimental results obtained in Phase 1. These models were used to simulate a population of water heaters and generate annual load profiles to assess the impacts on system-level power and residential load curves. Such population modeling allows for the inherent and permanent load reduction accomplished by the more efficient HPWHs to be considered, in addition to the temporal DR services the water heater can provide by switching ON or OFF as needed by utilities. The economic and emissions impacts of using large-tank water heaters in DR programs are then analyzed from the utility and consumer perspective, based on National Impacts Analysis in Phase 3. Phase 1 is discussed in this report. Details on Phases 2 and 3 can be found in the companion report (Cooke et al. 2014).

  20. Regenerative thermal purification of waste air using the pebble heater technology; Regenerative Thermische Abluftreinigung mit der Pebble-Heater-Technologie

    Energy Technology Data Exchange (ETDEWEB)

    Stevanovic, D.; Kapp, R. [Applikations- und Technikzentrum fuer Energieverfahrens-, Umwelt- und Stroemungstechnik (ATZ-EVUS), Sulzbach-Rosenberg (Germany); Rueskamp, B. [Lufttechnik Bayeurth, Goldkronach (Germany)

    2001-05-01

    Regenerative thermal post-combustion systems are used for purification of different types of process gases. They are getting increasingly important as legal specifications are getting more rigid. Low-cost solutions are sought for in an attempt to keep the investment cost and operating cost at a low level. [German] Regenerative thermische Nachverbrennungsanlagen werden fuer die Abreinigung verschiedenartiger Prozessgase genutzt. Sie werden immer wichtiger, weil sie die inzwischen sehr strengen gesetzlichen Richtlinien erfuellen. Um Investitions- und Betriebskosten niedrig zu halten, wird auch hier nach kostenguenstigeren Loesungen gesucht. (orig.)

  1. Three-phase heaters with common overburden sections for heating subsurface formations

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar, Harold J [Bellaire, TX

    2012-02-14

    A heating system for a subsurface formation is described. The heating system includes three substantially u-shaped heaters with first end portions of the heaters being electrically coupled to a single, three-phase wye transformer and second end portions of the heaters being electrically coupled to each other and/or to ground. The three heaters may enter the formation through a first common wellbore and exit the formation through a second common wellbore so that the magnetic fields of the three heaters at least partially cancel out in the common wellbores.

  2. Numerical and experimental study on heat pump water heater with PCM for thermal storage

    Energy Technology Data Exchange (ETDEWEB)

    Long, Jian-You; Zhu, Dong-Sheng [Key Laboratory of Enhanced Heat Transfer and Energy Conservation of the Ministry of Education, Academy of Chemistry and Energy, South China University of Technology, Guangzhou, Guangdong 510640 (China)

    2008-07-01

    An air source heat pump water heater with phase change material (PCM) for thermal storage was designed to take advantage of off-peak electrical energy. The heat transfer model of PCM was based upon a pure conduction formulation. Quasi-steady state method was used to calculate the temperature distribution and phase front location of PCM during thermal storage process. Temperature and thermal resistance iteration approach has been developed for the analysis of temperature variation of heat transfer fluid (HTF) and phase front location of PCM during thermal release process. To test the physical validity of the calculational results, experimental studies about storing heat and releasing heat of PCM were carried. Comparison between the calculational results and the experimental data shows good agreement. Graphical results including system pressure and input power of heat pump, time-wise variation of stored and released thermal energy of PCM were presented and discussed. (author)

  3. An experimental investigation with artificial sunlight of a solar hot-water heater

    Science.gov (United States)

    Simon, F. F.

    1976-01-01

    Thermal performance measurements were made of a commercial solar hot water heater in a solar simulator to determine basic performance characteristics of a traditional type of flat plate collector, with and without side reflectors (to increase the solar flux). Information on each of the following was obtained; (1) the effect of flow and incidence angle on the efficiency of a flat plate collector (but only without side reflectors); (2) transient performance under flow and nonflow conditions; (3) the effectiveness of reflectors to increase collector efficiency for a zero radiation angle at fluid temperatures required for solar air conditioning; and (4) the limits of applicability of a collector efficiency correlation based on the Hottel Whillier equation.

  4. 10 CFR 431.102 - Definitions concerning commercial water heaters, hot water supply boilers, and unfired hot water...

    Science.gov (United States)

    2010-01-01

    ... attached. Thermal efficiency for an instantaneous water heater, a storage water heater or a hot water... the amount of energy consumed by the water heater as measured during the thermal efficiency test... 10 Energy 3 2010-01-01 2010-01-01 false Definitions concerning commercial water heaters, hot...

  5. An Active Heater Control Concept to Meet IXO Type Mirror Module Thermal-Structural Distortion Requirement

    Science.gov (United States)

    Choi, Michael

    2013-01-01

    Flight mirror assemblies (FMAs) of large telescopes, such as the International X-ray Observatory (IXO), have very stringent thermal-structural distortion requirements. The spatial temperature gradient requirement within a FMA could be as small as 0.05 C. Con ventionally, heaters and thermistors are attached to the stray light baffle (SLB), and centralized heater controllers (i.e., heater controller boards located in a large electronics box) are used. Due to the large number of heater harnesses, accommodating and routing them is extremely difficult. The total harness length/mass is very large. This innovation uses a thermally conductive pre-collimator to accommodate heaters and a distributed heater controller approach. It minimizes the harness length and mass, and reduces the problem of routing and accommodating them. Heaters and thermistors are attached to a short (4.67 cm) aluminum portion of the pre-collimator, which is thermally coupled to the SLB. Heaters, which have a very small heater power density, and thermistors are attached to the exterior of all the mirror module walls. The major portion (23.4 cm) of the pre-collimator for the middle and outer modules is made of thin, non-conductive material. It minimizes the view factors from the FMA and heated portion of the precollimator to space. It also minimizes heat conduction from one end of the FMA to the other. Small and multi-channel heater controllers, which have adjustable set points and internal redundancy, are used. They are mounted to the mechanical support structure members adjacent to each module. The IXO FMA, which is 3.3 m in diameter, is an example of a large telescope. If the heater controller boards are centralized, routing and accommodating heater harnesses is extremely difficult. This innovation has the following advantages. It minimizes the length/mass of the heater harness between the heater controllers and heater circuits. It reduces the problem of routing and accommodating the harness on the

  6. Thermal hydraulic analysis of the annular flow helium heater design

    Science.gov (United States)

    Chen, N. C.; Sanders, J. P.

    1982-05-01

    Core support performance test (CSPT) by use of an existing facility, components flow test loop (CFTL), as part of the high temperature gas cooled reactor (HTGR) application program were conducted. A major objective of the CSPT is to study accelerated corrosion of the core graphite support structure in helium at reactor conditions. Concentration of impurities will be adjusted so that a 6 month test represents the 30 year reactor life. Thermal hydraulic and structural integrity of the graphite specimen, will be studied at high pressure of 7.24 MPa (1050 psi) and high temperature of 1000 deg C in a test vessel. To achieve the required high temperature at the test section, a heater bundle has to be specially designed and properly manufactured. Performance characteristics of the heater which were determined from an analysis based on this design are presented.

  7. Development of Exhaust Gas Driven Absorption Chiller-Heater

    Science.gov (United States)

    Inoue, Naoyuki; Endou, Tetsuya; Saito, Kiyoshi; Kawai, Sunao

    Waste heat from co-generation systems are usually recovered by hot water or steam, those are used to drive absorption refrigerators at cooling time, and those are used for heating via heat exchangers at heating time. However waste heat from micro gas turbines are discharged in the form of exhaust gas, it is simple that exhaust gas is directly supplied to absorption chiller-heaters. In the first report we studied cooling cycle, and this second paper, we evaluated various absorption heating cycles for exhaust gas driven absorption chiller-heaters, and adopted one of these cycles for the prototype machine. Also, we experimented with the prototype for wide range condition and got the heating characteristics. Based on the experimental data, we developed a simulation model of the static characteristics, and then studied how to increase the output by limited exhaust gas.

  8. DESIGN OF A 500W RESONANT INDUCTION HEATER

    Directory of Open Access Journals (Sweden)

    Bekir Sami SAZAK

    1999-01-01

    Full Text Available In this paper a complete design procedure for a 500W induction heating system is given. An induction heating system basically consists of a coil and a DC/AC inverter. The use of a single switch resonant inverter, which is operated with Discontinuous Conduction Mode (DCM, allows the switching device to turn off under zero current conditions, therefore switching losses are much reduced. This inverter system transforms the DC into AC for the induction heater coil. The proposed coil design method is applicable to a load of any shape so long as the coil surrounds the workpiece. The basis of this method of coil design is the reduction of the induction heater coil and workpiece to their equivalent resistance and inductance.

  9. Fabrication of light weight radioisotope heater unit hardware components

    Science.gov (United States)

    McNeil, Dennis C.

    1996-03-01

    The Light Weight Radioisotope Heater Unit (LWRHU) is planned to be used on the National Aeronautics and Space Administration (NASA) Cassini Mission, to provide localized thermal energy as strategic locations on the spacecraft. These one watt heater units will support the operation of many on-board instruments that require a specific temperature range to function properly. The system incorporates a fuel pellet encapsulated in a vented metallic clad fabricated from platinum-30% rhodium (Pt-30%Rh) tubing, sheet and foil materials. To complete the package, the clad assemblies are placed inside a combination of graphite components. This report describes the techniques employed by Mound related to the fabrication and sub assembly processes of the LWRHU clad hardware components. Included are details concerning configuration control systems, material procurement and certification, hardware fabrication specifics, and special processes that are utilized.

  10. Field Performance of Heat Pump Water Heaters in the Northeast

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, Carl [Consortium for Advanced Residential Buildings, Norfolk, CT (United States); Puttagunta, Srikanth [Consortium for Advanced Residential Buildings, Norfolk, CT (United States)

    2016-02-05

    Heat pump water heaters (HPWHs) are finally entering the mainstream residential water heater market. Potential catalysts are increased consumer demand for higher energy efficiency electric water heating and a new Federal water heating standard that effectively mandates use of HPWHs for electric storage water heaters with nominal capacities greater than 55 gallons. When compared to electric resistance water heating, the energy and cost savings potential of HPWHs is tremendous. Converting all electric resistance water heaters to HPWHs could save American consumers 7.8 billion dollars annually ($182 per household) in water heating operating costs and cut annual residential source energy consumption for water heating by 0.70 quads. Steven Winter Associates, Inc. embarked on one of the first in situ studies of these newly released HPWH products through a partnership with two sponsoring electric utility companies, National Grid and NSTAR, and one sponsoring energy efficiency service program administrator, Cape Light Compact. Recent laboratory studies have measured performance of HPWHs under various operating conditions, but publically available field studies have not been as available. This evaluation attempts to provide publicly available field data on new HPWHs by monitoring the performance of three recently released products (General Electric GeoSpring(TM), A.O. Smith Voltex(R), and Stiebel Eltron Accelera(R) 300). Fourteen HPWHs were installed in Massachusetts and Rhode Island and monitored for over a year. Of the 14 units, ten were General Electric models (50 gallon units), two were Stiebel Eltron models (80 gallon units), and two were A.O. Smith models (one 60-gallon and one 80-gallon unit).

  11. Field Performance of Heat Pump Water Heaters in the Northeast

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, C.; Puttagunta, S.

    2013-08-01

    Heat pump water heaters (HPWHs) are finally entering the mainstream residential water heater market. Potential catalysts are increased consumer demand for higher energy efficiency electric water heating and a new Federal water heating standard that effectively mandates use of HPWHs for electric storage water heaters with nominal capacities greater than 55 gallons. When compared to electric resistance water heating, the energy and cost savings potential of HPWHs is tremendous. Converting all electric resistance water heaters to HPWHs could save American consumers 7.8 billion dollars annually ($182 per household) in water heating operating costs and cut annual residential source energy consumption for water heating by 0.70 quads. Steven Winter Associates, Inc. embarked on one of the first in situ studies of these newly released HPWH products through a partnership with two sponsoring electric utility companies, National Grid and NSTAR, and one sponsoring energy efficiency service program administrator, Cape Light Compact. Recent laboratory studies have measured performance of HPWHs under various operating conditions, but publicly available field studies have not been as available. This evaluation attempts to provide publicly available field data on new HPWHs by monitoring the performance of three recently released products (General Electric GeoSpring(tm), A.O. Smith Voltex(r), and Stiebel Eltron Accelera(r)300). Fourteen HPWHs were installed in Massachusetts and Rhode Island and monitored for over a year. Of the 14 units, ten were General Electric models (50 gallon units), two were Stiebel Eltron models (80 gallon units), and two were A.O. Smith models (one 60-gallon and one 80-gallon unit).

  12. Performance Analysis and Modeling of Thermally Sprayed Resistive Heaters

    Science.gov (United States)

    Lamarre, Jean-Michel; Marcoux, Pierre; Perrault, Michel; Abbott, Richard C.; Legoux, Jean-Gabriel

    2013-08-01

    Many processes and systems require hot surfaces. These are usually heated using electrical elements located in their vicinity. However, this solution is subject to intrinsic limitations associated with heating element geometry and physical location. Thermally spraying electrical elements directly on surfaces can overcome these limitations by tailoring the geometry of the heating element to the application. Moreover, the element heat transfer is maximized by minimizing the distance between the heater and the surface to be heated. This article is aimed at modeling and characterizing resistive heaters sprayed on metallic substrates. Heaters were fabricated by using a plasma-sprayed alumina dielectric insulator and a wire flame-sprayed iron-based alloy resistive element. Samples were energized and kept at a constant temperature of 425 °C for up to 4 months. SEM cross-sectional observations revealed the formation of cracks at very specific locations in the alumina layer after thermal use. Finite-element modeling shows that these cracks originate from high local thermal stresses and can be predicted according to the considered geometry. The simulation model was refined using experimental parameters obtained by several techniques such as emissivity and time-dependent temperature profile (infra-red camera), resistivity (four-probe technique), thermal diffusivity (laser flash method), and mechanical properties (micro and nanoindentation). The influence of the alumina thickness and the substrate material on crack formation was evaluated.

  13. Conasauga near-surface heater experiment. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Krumhansl, J.L.

    1979-11-01

    The Conasauga Experiment was undertaken to begin assessment of the thermomechanical and chemical response of a specific shale to the heat resulting from emplacement of high-level nuclear wastes. Canister-size heaters were implanted in Conasauga shale in Tennessee. Instrumentation arrays wee placed at various depths in drill holes around each heater. The heaters operated for 8 months and, after the first 4 days, were maintained at 385/sup 0/C. Emphasis was on characterizing the thermal and mechanical response of the formation. Conduction was the major mode of heat transport; convection was perceptible only at temperatures above the boiling point of water. Despite dehydration of the shale at higher temperatures, in situ thermal conductivity was essentially constant and not a function of temperature. The mechanical response of the formation was a slight overall expansion, apparently resulting in a general decrease in permeability. Metallurgical observations were made, the stability of a borosilicate glass wasteform simulant was assessed, and changes in formation mineralogy and groundwater composition were documented. In each of these areas, transient nonequilibrium processes occur that affect material stability and may be important in determining the integrity of a repository. In general, data from the test reflect favorably on the use of shale as a disposal medium for nuclear waste.

  14. Control and Coordination of Frequency Responsive Residential Water Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Tess L.; Kalsi, Karanjit; Elizondo, Marcelo A.; Marinovici, Laurentiu D.; Pratt, Richard M.

    2016-07-31

    Demand-side frequency control can complement traditional generator controls to maintain the stability of large electric systems in the face of rising uncertainty and variability associated with renewable energy resources. This paper presents a hierarchical frequency-based load control strategy that uses a supervisor to flexibly adjust control gains that a population of end-use loads respond to in a decentralized manner to help meet the NERC BAL-003-1 frequency response standard at both the area level and interconnection level. The load model is calibrated and used to model populations of frequency-responsive water heaters in a PowerWorld simulation of the U.S. Western Interconnection (WECC). The proposed design is implemented and demonstrated on physical water heaters in a laboratory setting. A significant fraction of the required frequency response in the WECC could be supplied by electric water heaters alone at penetration levels of less than 15%, while contributing to NERC requirements at the interconnection and area levels.

  15. 欧盟家用空气源热泵热水器能效标准测试方法的研究%The Experimental Research on the European Coefficient of Performance Testing Methods of Household Air-source Heat-pump Water Heater

    Institute of Scientific and Technical Information of China (English)

    舒宏; 何林; 杨加政

    2015-01-01

    目前欧盟热泵热水器测试标准 EN 16147:2011,Heat pumps with electrically driven compressors- Testing and requirements for marking of domestic hot water units已于2011年7月开始实施,但国内的标准GB/T 23137-2008并未有相应的更改。本文将通过测试静态加热式热泵热水器来对比分析其能效测试结果相对于国标测试方法的不同,并分析出目前国内开发的主流的热泵热水器在售后使用时的真正能效是否节能,并考虑到售后使用的能效情况,提出设计热泵热水器时的优化节能方向和售后客户使用的节能注意事项。%The European standard, EN 16147:2011,Heat pumps with electrically driven compressors - Testing and requirements for marking of domestic hot water units, has been put into effect from July, 2011. However, Chinese na-tional standard is still the GB/T 23137-2008 which hasn’t made the corresponding changes. In this paper, it tests the static heating water heat pump and use its data to compare and analyze the differences of Chinese national standard and European standard, including the coefficient of performance which used by users. Furthermore, this paper points out the development direction of energy conservation of heat-pump water heater and the matters needing attention for us-ers in consideration of the coefficient of performance.

  16. Analyzing the possibility of constructing the air heating system for an integrated solid fuel gasification combined-cycle power plant

    Science.gov (United States)

    Mikula, V. A.; Ryzhkov, A. F.; Val'tsev, N. V.

    2015-11-01

    Combined-cycle power plants operating on solid fuel have presently been implemented only in demonstration projects. One of possible ways for improving such plants consists in making a shift to hybrid process circuits of integrated gasification combined-cycle plants with external firing of solid fuel. A high-temperature air heater serving to heat compressed air is a key element of the hybrid process circuit. The article describes application of a high-temperature recuperative metal air heater in the process circuit of an integrated gasification combined-cycle power plant (IGCC). The available experience with high-temperature air heating is considered, and possible air heater layout arrangements are analyzed along with domestically produced heat-resistant grades of steel suitable for manufacturing such air heater. An alternative (with respect to the traditional one) design is proposed, according to which solid fuel is fired in a noncooled furnace extension, followed by mixing the combustion products with recirculation gases, after which the mixture is fed to a convective air heater. The use of this design makes it possible to achieve considerably smaller capital outlays and operating costs. The data obtained from thermal and aerodynamic calculations of the high-temperature air heater with a thermal capacity of 258 MW for heating air to a temperature of up to 800°C for being used in the hybrid process circuit of a combined-cycle power plant are presented.

  17. Experimental Analysis on Solar Desiccant Air Conditioner

    Directory of Open Access Journals (Sweden)

    Dr. U. V. Kongre, C. M. Singh, A. B. Biswas

    2014-05-01

    Full Text Available The experiment investigated and evaluated the feasibility of an solar desiccant air conditioner. Its effectiveness as a possible air conditioner option used in household air conditioner or as an energy efficient and environmentally friendly alternative to conventional air conditioning units used in houses are evaluated. A solar water heater was used as heat gain. The model utilizes the technology of solar air conditioner system. The purpose in the long term would be reduced the consumption of electricity used for air conditioning, reduce harmful emission and hence saving money.

  18. Assessing the Energy Savings of Tankless Water Heater Retrofits in Public Housing

    Energy Technology Data Exchange (ETDEWEB)

    Ries, R. [Univ. of Florida, Gainesville, FL (United States). Building Energy Efficient Housing for America (BEEHA)Team; Walters, R. [Univ. of Florida, Gainesville, FL (United States). Building Energy Efficient Housing for America (BEEHA)Team; Dwiantoro, D. [Univ. of Florida, Gainesville, FL (United States). Building Energy Efficient Housing for America (BEEHA)Team

    2013-01-01

    This report describes the methodology, analysis, and findings from a case study of a 110 unit retrofit of gas tankless water heaters in a hot/humid climate in Alachua County, Florida.The gas-fired tank type water heaters in the housing units were replaced with gas-fired tankless water heaters as part of a federal program that targeted reduced energy use in public housing.

  19. Assessing the Energy Savings of Tankless Water Heater Retrofits in Public Housing

    Energy Technology Data Exchange (ETDEWEB)

    Ries, R.; Walters, R.; Dwiantoro, D.

    2013-01-01

    This report describes the methodology, analysis, and findings from a case study of a 110 unit retrofit of gas tankless water heaters in a hot/humid climate in Alachua County, Florida. The housing units had their gas-fired tank type water heaters replaced with gas-fired tankless water heaters as part of a federal program that targeted reduced energy use in public housing.

  20. Comparison of Simulation and Experimental Results of Class - D Inverter Fed Induction Heater

    Directory of Open Access Journals (Sweden)

    S. Rama Reddy

    2010-10-01

    Full Text Available This research deals w ith simulation and experimentation of closed loop controlled class-D inverter fed induction heater system. This converter has reduced switching losses, stress and increased power density. The inverter system is designed and the simulation is done using Matlab. The results of simulation and experimentation are presented. The induction heater system uses embedded controller to generate driving pulses. The objective is to develop an induction heater system with minimum hardware.

  1. REVIEW ON POROUS AND NON-POROUS FLAT PLATE AIR COLLECTOR WITH MIRROR ENCLOSURE

    Directory of Open Access Journals (Sweden)

    M. PRADHAPRAJ,

    2010-09-01

    Full Text Available In solar air heater, flat plat collectors are the best heat transferring devices. But the effectiveness of these collectorsis very low because of lack of technology. Solar assisted heated air is successfully used for drying applications and space heating under controlled conditions. From the solar flat plate air heater the hot air is transferred to a conventional dryer or to the combined heater and drying chamber directly. Hence, solar assisted air heaters arecheaper and reliable. The important factors affecting these systems are the solar radiation, mechanical loading, temperature and leakage. The air heater efficiency depends on the design of the system as well as the construction materials and the assembly. The solar air heating systems has acceptable life span of 15 to 20 years. The addition ofside mirror enclosures is to increase the amount of solar radiation absorption at the collector plate so that the collector increases the yield and operate in a higher temperature range. Therefore with the addition of side mirrors one can able to maximize the output of fixed flat plate collectors. A flat plate air collector will be more efficient if it is made up of porous medium when comparing it with the non porous collectors according to the study. In this paper, the performances of porous and non-porous absorber plates are discussed. Also the possible methods of finding out air leakages and the methodology adopted for the performance and efficiency calculations are also discussed.

  2. 14 CFR 29.859 - Combustion heater fire protection.

    Science.gov (United States)

    2010-01-01

    ... air ducts. Each ventilating air duct passing through any fire zone must be fireproof. In addition— (1) Unless isolation is provided by fireproof valves or by equally effective means, the ventilating air duct... the ventilating airstream. (c) Combustion air ducts. Each combustion air duct must be fireproof for...

  3. Benchmark Tests for Stirling Convertor Heater Head Life Assessment Conducted

    Science.gov (United States)

    Krause, David L.; Halford, Gary R.; Bowman, Randy R.

    2004-01-01

    A new in-house test capability has been developed at the NASA Glenn Research Center, where a critical component of the Stirling Radioisotope Generator (SRG) is undergoing extensive testing to aid the development of analytical life prediction methodology and to experimentally aid in verification of the flight-design component's life. The new facility includes two test rigs that are performing creep testing of the SRG heater head pressure vessel test articles at design temperature and with wall stresses ranging from operating level to seven times that (see the following photograph).

  4. Integral finned heater and cooler for stirling engines

    Science.gov (United States)

    Corey, John A.

    1984-01-01

    A piston and cylinder for a Stirling engine and the like having top and bottom meshing or nesting finned conical surfaces to provide large surface areas in close proximity to the working gas for good thermal (addition and subtraction of heat) exchange to the working gas and elimination of the usual heater and cooler dead volume. The piston fins at the hot end of the cylinder are perforated to permit the gas to pass into the piston interior and through a regenerator contained therein.

  5. High Efficiency R-744 Commercial Heat Pump Water Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Elbel, Dr. Stefan W.; Petersen, Michael

    2013-04-25

    The project investigated the development and improvement process of a R744 (CO2) commercial heat pump water heater (HPWH) package of approximately 35 kW. The improvement process covered all main components of the system. More specific the heat exchangers (Internal heat exchanger, Evaporator, Gas cooler) as well as the expansion device and the compressor were investigated. In addition, a comparison to a commercially available baseline R134a unit of the same capacity and footprint was made in order to compare performance as well as package size reduction potential.

  6. Zoned electrical heater arranged in spaced relationship from particulate filter

    Science.gov (United States)

    Gonze, Eugene V [Pinckney, MI

    2011-11-15

    A system comprises a particulate matter (PM) filter that comprises an upstream end for receiving exhaust gas and a downstream end. A zoned heater is arranged spaced from the upstream end and comprises N zones, where N is an integer greater than one, wherein each of the N zones comprises M sub-zones, where M is an integer greater than one. A control module selectively activates at least a selected one of the N zones to initiate regeneration in downstream portions of the PM filter from the one of the N zones and deactivates non-selected ones of the N zones.

  7. 超声速燃烧地面试验的蓄热式加热器及其关键技术%Thermal energy storage heater and its key technologies for supersonic combustion ground test facilities

    Institute of Scientific and Technical Information of China (English)

    李龙飞; 王延涛; 杨伟东; 洪流

    2012-01-01

    为了模拟飞行状态下进入超燃冲压发动机燃烧室的高焓空气,在地面模拟试验中需要对空气加热,可再生蓄热式加热器是一种能提供相对纯净高焓空气的试验设备。介绍了蓄热式加热器的工作原理与特点,分析了关键技术。结果表明,蓄热式加热器具有加热空气总温高、流量大和相对纯净的优点,是我国超燃冲压发动机地面试验的发展趋势,但蓄热阵材料、加热器结构、超高温阀和大范围调节预热燃烧器等是关键技术,有待进一步研究和攻关。%In order to simulate the air temperature in the combustion chamber of scramjet,the air used by the ground simulation test should be heated.This paper presents the design specification of a cored brick storage heater,which can supply high temperature clean air to meet the demands of supersonic combustion experiments.Key technologies of developing thermal energy storage heater are analyzed.The results show that with proper material and structural design,it is possible to use a thermal energy storage heater to obtain clean air flow of Mach 6.However,real performance of materials,the heater structure,the ultra high-temperature valve and gas generator still need to be studied to solve the remaining issues in the thermal energy storage heater.

  8. Simple Retrofit High-Efficiency Natural Gas Water Heater Field Test

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, Ben [NorthernSTAR, St. Paul, MN (United States)

    2017-03-28

    High performance water heaters are typically more time consuming and costly to install in retrofit applications, making high performance water heaters difficult to justify economically. However, recent advancements in high performance water heaters have targeted the retrofit market, simplifying installations and reducing costs. Four high efficiency natural gas water heaters designed specifically for retrofit applications were installed in single-family homes along with detailed monitoring systems to characterize their savings potential, their installed efficiencies, and their ability to meet household demands. The water heaters tested for this project were designed to improve the cost-effectiveness and increase market penetration of high efficiency water heaters in the residential retrofit market. The retrofit high efficiency water heaters achieved their goal of reducing costs, maintaining savings potential and installed efficiency of other high efficiency water heaters, and meeting the necessary capacity in order to improve cost-effectiveness. However, the improvements were not sufficient to achieve simple paybacks of less than ten years for the incremental cost compared to a minimum efficiency heater. Significant changes would be necessary to reduce the simple payback to six years or less. Annual energy savings in the range of $200 would also reduce paybacks to less than six years. These energy savings would require either significantly higher fuel costs (greater than $1.50 per therm) or very high usage (around 120 gallons per day). For current incremental costs, the water heater efficiency would need to be similar to that of a heat pump water heater to deliver a six year payback.

  9. A micro solar heater for portable energy generation

    Science.gov (United States)

    Zimmerman, Raúl; Morrison, Graham; The, Owen; Rosengarten, Gary

    2007-12-01

    This study presents a new concept that combines microtechnology with solar thermal energy to provide a free portable energy source. A water-methanol mixture flows through an array of parallel microchannels which are fabricated into a silicon matrix using conventional micro-fabrication techniques. A vacuum layer is interposed between the channels and the external surface to thermally insulate the channels from the ambient temperature. A selective coating is deposited on one of the vacuum walls to absorb the short wavelength incoming radiation and reduce the long wavelength radiation, hence reducing the heat losses. A geometry and material optimization is still being developed in order to obtain the highest possible efficiency for the micro-heater, while keeping a low pressure drop in the micro-channels. The methanol outlet temperature is predicted to be higher than 250°C. This temperature is required for hydrogen production in a methanol reforming micro-reactor. Therefore, it is envisaged that the micro-solar heater will supply the thermal energy needed for hydrogen generation, that can later be used as fuel for microfuel cells. Both technologies can be integrated in a portable device.

  10. Evaluation of Tube Wall Thickness of Feed Water Heater

    Science.gov (United States)

    Uchikura, Takahisa; Morisaki, Koichi; Hamada, Seiichi

    With regard to the high pressure (HP) feed water heater of thermal power plant at Tokyo Electric Power Company (TEPCO) sites, inspection of feed water (FW) tubes wall thickness are conducted whenever required such that frequent tube leak occurs. As a standard inspection methodology, FW heater is disassembled during planned outage, tube wall thickness is measured by the ultrasonic pulse techique (UT), then plugs are installed at the both ends of FW tube if its measured wall thickness is found below calculated threshold. However, the root causes of wall thinning of FW tube are various such as erosion and corrosion, based on wall thinning condition, the above threshold is not applied but utilizing the other technically well-grounded evaluation method is sometimes more rational. Therefore, TEPCO classified wall-thinning condition based on inspection data and established technically well-grounded and rational evaluation methodologies of FW tube wall thickness to suite each wall thinning condition. Moreover, with recent improvement of inspection technique, technology enabled faster, larger amount, and more accurate data acquisition, TEPCO has developed the systematized evaluation methodology that can transact data acquisition and evaluation simultaneously. This article introduces the logic of evaluation methods and examined algorithms to make them systematized.

  11. Eleana near-surface heater experiment final report

    Energy Technology Data Exchange (ETDEWEB)

    Lappin, A R; Thomas, R K; McVey, D F

    1981-04-01

    This report summarizes the results of a near-surface heater experiment operated at a depth of 23 m in argillite within the Eleana Formation on the Nevada Test Site (NTS). The test geometrically simulated emplacement of a single canister of High-Level Waste (HLW) and was operated at a power level of 2.5 kW for 21 days, followed by 3.8 kW to 250 days, when the power was turned off. Below 85 to 100{sup 0}C, there was good agreement between modeled and measured thermal results in the rock and in the emplacement hole, except for transient transport of water in the heater hole. Above 100{sup 0}C, modeled and measured thermal results increasingly diverged, indicating that the in-situ rock-mass thermal conductivity decreased as a result of dehydration more than expected on the basis of matrix properties. Correlation of thermomechanical modeling and field results suggests that this decrease was caused by strong coupling of thermal and mechanical behavior of the argillite at elevated temperatures. No hole-wall decrepitation was observed in the experiment; this fact and the codrrelation of modeled and measured results at lower temperatures indicate that there is no a priori reason to eliminate argillaceous rocks from further consideration as a host rock for nuclear wastes.

  12. High-performance, bare silver nanowire network transparent heaters.

    Science.gov (United States)

    Ergun, Orcun; Coskun, Sahin; Yusufoglu, Yusuf; Unalan, Husnu Emrah

    2016-11-04

    Silver nanowire (Ag NW) networks are one of the most promising candidates for the replacement of indium tin oxide (ITO) thin films in many different applications. Recently, Ag-NW-based transparent heaters (THs) showed excellent heating performance. In order to overcome the instability issues of Ag NW networks, researchers have offered different hybrid structures. However, these approaches not only require extra processing, but also decrease the optical performance of Ag NW networks. So, it is important to investigate and determine the thermal performance limits of bare-Ag-NW-network-based THs. Herein, we report on the effect of NW density, contact geometry, applied bias, flexing and incremental bias application on the TH performance of Ag NW networks. Ag-NW-network-based THs with a sheet resistance and percentage transmittance of 4.3 Ω sq(-1) and 83.3%, respectively, and a NW density of 1.6 NW μm(-2) reached a maximum temperature of 275 °C under incremental bias application (5 V maximum). With this performance, our results provide a different perspective on bare-Ag-NW-network-based transparent heaters.

  13. Asymmetric Pentagonal Metal Meshes for Flexible Transparent Electrodes and Heaters.

    Science.gov (United States)

    Lordan, Daniel; Burke, Micheal; Manning, Mary; Martin, Alfonso; Amann, Andreas; O'Connell, Dan; Murphy, Richard; Lyons, Colin; Quinn, Aidan J

    2017-02-08

    Metal meshes have emerged as an important class of flexible transparent electrodes. We report on the characteristics of a new class of asymmetric meshes, tiled using a recently discovered family of pentagons. Micron-scale meshes were fabricated on flexible polyethylene terephthalate substrates via optical lithography, metal evaporation (Ti 10 nm, Pt 50 nm), and lift-off. Three different designs were assessed, each with the same tessellation pattern and line width (5 μm), but with different sizes of the fundamental pentagonal unit. Good mechanical stability was observed for both tensile strain and compressive strain. After 1000 bending cycles, devices subjected to tensile strain showed fractional resistance increases in the range of 8-17%, while devices subjected to compressive strain showed fractional resistance increases in the range of 0-7%. The performance of the pentagonal metal mesh devices as visible transparent heaters via Joule heating was also assessed. Rapid response times (∼15 s) at low bias voltage (≤5 V) and good thermal resistance characteristics (213-258 °C cm(2)/W) were found using measured thermal imaging data. Deicing of an ice-bearing glass coupon on top of the transparent heater was also successfully demonstrated.

  14. Analysis of Large- Capacity Water Heaters in Electric Thermal Storage Programs

    Energy Technology Data Exchange (ETDEWEB)

    Cooke, Alan L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Anderson, David M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Winiarski, David W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carmichael, Robert T. [Cadeo Group, Washington D. C. (United States); Mayhorn, Ebony T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fisher, Andrew R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-03-17

    This report documents a national impact analysis of large tank heat pump water heaters (HPWH) in electric thermal storage (ETS) programs and conveys the findings related to concerns raised by utilities regarding the ability of large-tank heat pump water heaters to provide electric thermal storage services.

  15. High voltage bus and auxiliary heater control system for an electric or hybrid vehicle

    Science.gov (United States)

    Murty, Balarama Vempaty

    2000-01-01

    A control system for an electric or hybrid electric vehicle includes a vehicle system controller and a control circuit having an electric immersion heater. The heater is electrically connected to the vehicle's high voltage bus and is thermally coupled to a coolant loop containing a heater core for the vehicle's climate control system. The system controller responds to cabin heat requests from the climate control system by generating a pulse width modulated signal that is used by the control circuit to operate the heater at a duty cycle appropriate for the amount of cabin heating requested. The control system also uses the heater to dissipate excess energy produced by an auxiliary power unit and to provide electric braking when regenerative braking is not desirable and manual braking is not necessary. The control system further utilizes the heater to provide a safe discharge of a bank of energy storage capacitors following disconnection of the battery or one of the high voltage connectors used to transmit high voltage operating power to the various vehicle systems. The control circuit includes a high voltage clamping circuit that monitors the voltage on the bus and operates the heater to clamp down the bus voltage when it exceeds a pre-selected maximum voltage. The control system can also be used to phase in operation of the heater when the bus voltage exceeds a lower threshold voltage and can be used to phase out the auxiliary power unit charging and regenerative braking when the battery becomes fully charged.

  16. 76 FR 28662 - Industrial, Commercial, and Institutional Boilers and Process Heaters and Commercial and...

    Science.gov (United States)

    2011-05-18

    ... AGENCY 40 CFR Parts 60 and 63 RIN 2060-AQ25; 2060-AO12 Industrial, Commercial, and Institutional Boilers... Major Sources: Industrial, Commercial, and Institutional Boilers and Process Heaters'' and ``Standards...: Industrial, Commercial, and Institutional Boilers and Process Heaters'': Mr. Brian Shrager, Energy...

  17. Tankless water heaters fill the bill at fast-food restaurants

    Energy Technology Data Exchange (ETDEWEB)

    1988-02-01

    This article explains why Kentucky Fried Chicken has installed a PH-24 water heater. The tankless water heater meets the restaurant's criteria for space spacing, flow rates, certification and availability, and money saving efficiency. This article describes the system and its advantages.

  18. 75 FR 21981 - Energy Conservation Program: Energy Conservation Standards for Residential Water Heaters, Direct...

    Science.gov (United States)

    2010-04-27

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY 10 CFR Part 430 RIN 1904-AA90 Energy Conservation Program: Energy Conservation Standards for Residential Water Heaters, Direct Heating Equipment, and Pool Heaters Correction In rule document 2010-7611 beginning...

  19. Demonstration of a heat pump water heater. Volume 3. Design report

    Energy Technology Data Exchange (ETDEWEB)

    Sloane, B.D.; Krise, R.C.; Kent, D.D.

    1979-12-01

    Work performed during the pilot run manufacturing and laboratory testing stages of a heat pump water heater for residential installations is described. A general description of the heat pump water heater is provided, as are detailed discussions of individual components. Also included is a description of the pilot run manufacturing facility and experience, laboratory operations, and laboratory test data.

  20. 46 CFR 52.01-35 - Auxiliary, donkey, fired thermal fluid heater, and heating boilers.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Auxiliary, donkey, fired thermal fluid heater, and... requirements for miscellaneous boiler types, such as donkey, fired thermal fluid heater, heating boiler, etc... (CONTINUED) MARINE ENGINEERING POWER BOILERS General Requirements § 52.01-35 Auxiliary, donkey, fired...

  1. CFD Study of Fluid Flow in an All-glass Evacuated Tube Solar Water Heater

    DEFF Research Database (Denmark)

    Ai, Ning; Fan, Jianhua; Li, Yumin

    2008-01-01

    Abstract: The all-glass evacuated tube solar water heater is one of the most widely used solar thermal technologies. The aim of the paper is to investigate fluid flow in the solar water heater by means of computational fluid dynamics (CFD). The investigation was carried out with a focus...

  2. Analysis of Uncertainties in Protection Heater Delay Time Measurements and Simulations in Nb$_{3}$Sn High-Field Accelerator Magnets

    CERN Document Server

    Salmi, Tiina; Marchevsky, Maxim; Bajas, Hugo; Felice, Helene; Stenvall, Antti

    2015-01-01

    The quench protection of superconducting high-field accelerator magnets is presently based on protection heaters, which are activated upon quench detection to accelerate the quench propagation within the winding. Estimations of the heater delay to initiate a normal zone in the coil are essential for the protection design. During the development of Nb3Sn magnets for the LHC luminosity upgrade, protection heater delays have been measured in several experiments, and a new computational tool CoHDA (Code for Heater Delay Analysis) has been developed for heater design. Several computational quench analyses suggest that the efficiency of the present heater technology is on the borderline of protecting the magnets. Quantifying the inevitable uncertainties related to the measured and simulated delays is therefore of pivotal importance. In this paper, we analyze the uncertainties in the heater delay measurements and simulations using data from five impregnated high-field Nb3Sn magnets with different heater geometries. ...

  3. High thermal performance of SnO2:F thin transparent heaters with scattered metal nanodots.

    Science.gov (United States)

    Hudaya, Chairul; Jeon, Bup Ju; Lee, Joong Kee

    2015-01-14

    Facile production and novel transparent heaters consisting of fluorine-doped tin oxide (SnO2:F or FTO) thin films covered with three different scattered metal nanodots (Cr-nd, NiCr-nd and Ni-nd) prepared by plasma-enhanced sputtering system and electron cyclotron resonance-metal organic chemical vapor deposition are investigated. The heaters exhibit excellent optical transmittances of over 85% and superior saturated temperatures of more than 80 °C when a relatively low 12 V DC is supplied. The scattered metal nanodots FTO heaters successfully improve the specific power of bare FTO heater by 21, 15, and 12% for NiCr-nd FTO, Cr-nd FTO, and Ni-nd FTO, respectively. These results reveal that the FTO transparent heaters with scattered metal nanodots are the suitable heating materials that can be applied for various functional devices.

  4. Evaluation and certification of heater assemblies developed for thermal vacuum acceptance testing

    Science.gov (United States)

    Allen, J. E.

    1986-01-01

    Preparation of Rockwell International's Thermal Vacuum Chamber for acceptance testing of a mass produced satellite required the development of unique quartz lamp and hot wire heater assemblies. Testing performed on the basic elements of these heaters is described, as is the final testing done to certify that the heater assemblies meet the thermal requirements for acceptance testing. The methods and procedures of thermal mapping used during the development and final certification of these heater assemblies are presented. The absence of a definitive standard for determining flux distribution and heating boundaries for heaters of this type required the development of a test plan incorporating several thermal mapping techniques. These techniques include the development of heat flux using a multiple calorimeter array for both vacuum and ambient test conditions, and a photographic method for detecting heating boundaries. The test plan and thermal mapping techniques are discussed.

  5. Proceedings of a workshop on the utilization of coal fuels in process heaters

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-01

    Almost 5% of the nation's energy consumption takes place in tubular process heaters. Currently, these units are gas- and, to a lesser extent, oil-fired. Process heaters provide energy for refining petroleum and the manufacture of numerous chemicals and petrochemicals. Since the current state-of-the-art, using waste heat recovery and forced draft burners, can achieve thermal efficiencies of about 90%, it is unlikely that current process heat and fuel requirements will be dramatically reduced by process modifications and/or conservation measures. Hence, if this sizeable, inexorable drain on our fluid petroleum reserves is to be halted, it seems reasonable to consider the utilization of coal and/or coal-based fuels to fire process heaters. In order to assess the feasibility and potential for a coal-based process heater industry, Brookhaven National Laboratory (BNL) organized a workshop to define and explore the various problems that must be solved in order to burn coal in process heaters. A primary aim of the workshop was to consider the design methodology for process heaters when firing coal and compare it to those for gas and oil firing. The overall conclusions were: that retrofitting present process heaters to coal fuel was impractical; that it would be difficult to fit larger heaters designed to burn coal into present refineries; that there would be difficulties with process heaters burning coal; and that a better approach would be one large utility coal heater with a circulating heat transfer medium. Seven papers have been entered individually into EDB and ERA. (LTN)

  6. Air-to-water heat pumps for the home

    Energy Technology Data Exchange (ETDEWEB)

    Bodzin, S. [ed.

    1997-07-01

    Heat pump water heaters may be on the rise again. Retrofitters have shied away from this form of water heating due to concerns about cost, moise, efficiency, and maintaenance. Recent advances have overcome some of these problems and are helping the technology find a niche in both hot and cold climates. The topics covered in this article include the following: how heat pump water heaters work; air source from where to where, including air conditioning, heat recovery ventilation, hybrid systems; nuisances; maintenance; costs; to install or not to install; performance: a trick to quantify. 2 figs.

  7. 10 CFR 431.106 - Uniform test method for the measurement of energy efficiency of commercial water heaters and hot...

    Science.gov (United States)

    2010-01-01

    ... Instantaneous Water Heaters and Hot Water Supply Boilers* Thermal Efficiency ANSI Z21.10.3-1998, § 2.9** A. For... Instantaneous Water Heaters and Hot Water Supply Boilers* Thermal Efficiency ANSI Z21.10.3-1998, § 2.9** (2) Oil...) Assume that the thermal efficiency (Et) of electric water heaters with immersed heating elements is...

  8. Analysis of thermal stresses in horizontal delivery water heaters

    Science.gov (United States)

    Bilan, A. V.; Plotnikov, P. N.

    2016-11-01

    Analysis of thermal stresses in tubes and a compensator, taking into account water heating in each heater bunch and temperature at which its mounting is implemented, and of stresses on pressure is presented. The 3D-model of the horizontal delivery water heater of PSG-4900-0.3-1.14 type is used. The tube plate is represented as the 3D-body with 6863 holes with offset center of the perforated area, the steam space shell is represented as a cylindrical casing, the bottoms of water chambers are considered as elliptical casings, the four-lens compensator is represented in the form of toroidal casings, and the tubes are considered as beams operating in tensile-compression and bending in two planes. Calculations were carried out for different temperatures of superheated steam and a steam space shell, respectively, as well as designs with compensator and without it. Various temperature values of the tubes on the passes were calculated and set. The studies were carried out taking into account nonaxis-symmetrical spacing the tube plate and compensator deformation. The calculation results of tensile-compression stresses in the tubes are presented. Furthermore, the central tubes experience compressive stresses, whose maximal values take place on the border between the tubes of the fourth and of the first passes. For its decrease, it is recommended to increase the distance between the tubes of these passes. The tension stresses in the peripheral tubes are the maximal stresses. To reduce the stresses and, therefore, increase service life of the delivery water heater at using wet or superheated (not more than by 30-50°C) steam in it (the larger value refers to the brass tubes and the water pressure of 1.6-2.5 MPa), it is necessary to recommend the noncompensatory design at using the steam superheated by more than 30-50°C (at Ural Turbine Works, it is the turbines of T-250/300-23.5 and T-113/145-12.4 types with intermediate superheating) and to recommend the installation of the

  9. Prediction of heater power distribution in radiative cylindrical furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Ravichandran, M.; Dilber, I.; Torok, D.

    1999-07-01

    In the design of long radiative cylindrical furnaces, it is important to control the temperature variation along the furnace walls and consequently the temperature distribution in the processed material by selectively adjusting the power input to heater rods located circumferentially around the furnace walls. The heaters are grouped in zones located at different axial locations. By adjusting the power to each zone a specified temperature distribution along the furnace can be attained. The radiative interchange between different axial zones of the furnace affects the temperature distribution; this interchange is also impacted by the shadowing caused by the presence of the load, i.e. the processed material. A desired temperature distribution can only be achieved by selectively changing the power input to the heaters. For an a priori assessment of the commercial viability of using process friendly temperature distributions, it is necessary to determine: (a) the maximum power demand from each zone; (b) if active cooling is inevitable and (c) the bounds on temperature distribution that can be achieved without active cooling. It is therefore extremely useful to be able to predict the input power distribution for achieving desired furnace temperature profiles. For a given power input, the temperature distribution inside the furnace could be obtained by using a general purpose Computational Fluid Dynamics (CFD) software, such as FIDAP. A new methodology is developed within the framework of FIDAP software to eliminate the manual trial and error method. The method is based on obtaining the sensitivity of the temperature at the desired locations of the furnace as a function of the power input to the heating elements. Using these sensitivity coefficients, an iterative scheme is designed to adjust the boundary conditions (power to the heating elements in this case) based on the discrepancy of the solution temperatures from the desired temperature distribution. For each of these

  10. Heat Pump Water Heater Durabliltiy Testing - Phase II

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, VAND.

    2004-05-29

    Ten heat pump water heaters (HPWH) were placed in an environmentally controlled test facility and run through a durability test program of approximately 7300 duty cycles (actual cycles accumulated ranged from 6640 to 8324 for the ten units). Five of the units were upgraded integral types (HPWH mounted on storage tank, no pump) from the same manufacturer as those tested in our first durability program in 2001 (Baxter and Linkous, 2002). The other five were ''add-on'' type units (HPWH with circulation pump plumbed to a separate storage tank) from another manufacturer. This durability test was designed to represent approximately 7-10 years of normal operation to meet the hot water needs of a residence. The integral units operated without incident apart from two control board failures. Both of these were caused by inadvertent exposure to very hot and humid (>135 F dry bulb and >120 F dew point) conditions that occurred due to a test loop failure. It is not likely that any residential water heater would be installed where such conditions were expected so these failures are not considered a long-term reliability concern. Two of the integral HPWHs featured a condensate management system (CMS) option that effectively eliminated any need for an evaporator condensate drain, but imposed significant efficiency penalties when operating in high humidity ambient conditions. The add-on units experienced no operational failures (breakdowns with loss of hot water production) during the course of the testing. However, their control systems exhibited some performance degradation under the high temperature, high humidity test conditions--HPWHs would shut off with tank water temperatures 15-20 F lower than when operating under moderate ambient conditions. One unit developed a refrigerant leak during the test program and lost about 50% of its charge resulting in reduced efficiency. Efficiency measurements on all the integral units and four of the add-on units showed

  11. Controlled cellular fusion using optically trapped plasmonic nano-heaters

    Science.gov (United States)

    Bahadori, Azra; Lund, Andreas R.; Semsey, Szabolcs; Oddershede, Lene B.; Bendix, Poul M.

    2016-09-01

    Optically trapped plasmonic nano-heaters are used to mediate efficient and controlled fusion of biological membranes. The fusion method is demonstrated by optically trapping plasmonic nanoparticles located in between vesicle membranes leading to rapid lipid and content mixing. As an interesting application we show how direct control over fusion can be used for studying diffusion of peripheral membrane proteins and their interactions with membranes and for studying protein reactions. Membrane proteins encapsulated in an inert vesicle can be transferred to a vesicle composed of negative lipids by optically induced fusion. Mixing of the two membranes results in a fused vesicle with a high affinity for the protein and we observe immediate membrane tubulation due to the activity of the protein. Fusion of distinct membrane compartments also has applications in small scale chemistry for realizing pico-liter reactions and offers many exciting applications within biology which are discussed here.

  12. Results of MPBX studies at the single heater test

    Energy Technology Data Exchange (ETDEWEB)

    Blair, S. C.,LLNL

    1997-10-01

    We have developed an extensometer for measurement of distance and displacements in a geologic repository for high-level nuclear waste. This is an optical extensometer that measures distance using a modulated laser beam. In this design, reflecting targets are placed at desired measurement locations, and distance between each target and an optical head are measured repeatedly using the modulated laser beam. Moreover, all electronic and moving parts are located outside of the hostile or difficult environment as the optical head is connected to the laser, switching and signal analysis hardware using optical fibers. A reference beam is utilized to provide direct correction of system behavior. `Be system also - utilizes movable reflective anchors that can be repositioned if desired. We have installed the system in the Single Heater Test being conducted in Alcove 5 of the Exploratory Studies Facility at Yucca Mountain, and report preliminary results.

  13. THE HEAT AND FLUID FLOW ANALYSIS FOR WATER HEATER

    Directory of Open Access Journals (Sweden)

    Chien-Nan Lin

    2011-01-01

    Full Text Available In this paper, the heat transfer and fluid flow are studied for the water heater of RV cars, in which the hot water is heated by the combustion energy of liquefied petroleum gases. Three types of combustion tubes are performed in this investigation, which are circular tube, elliptic tube and elliptic tube with screwed wire inserted. The heat transfer performances of numerical simulation results are compared with those of the experimental works; they are in good trend agreement. The elliptic combustion tube performs better than the circular one, which indicates the average 7% energy saving for the elliptic combustion tube and 12% energy saving for the elliptic combustion tube with screwed wire under static heating.

  14. Modelling of Closed Loop Class E Inverter Based Induction Heater

    Directory of Open Access Journals (Sweden)

    S. Arumugam

    2011-01-01

    Full Text Available This study presents simulation of class E inverter based induction heater system using simulink. DC is converted into high frequency AC using class E inverter. This high frequency AC is used for induction heating. Closed loop systems are modeled and they are simulated using Mat lab Simulink.The results of closed loop systems are presented. The proposed amplifier with two series-parallel resonant load networks will allow sinusoidal output voltage to be achieved by associating with the positive and negative quasi-sinusoidal waveforms. The complementarily activated configuration will provide continuous high-ripple-frequency inputcurrent waveforms; this approach significantly reduces electromagnetic interference and requires very little filtering. With the symmetry of the push-pull Class-E Circuit, there is the additional benefit that the even harmonics are suppressed at the load, and thus there are fewer harmonic distortions.

  15. FEM Optimal Design of Wind Energy-based Heater

    Directory of Open Access Journals (Sweden)

    Tiberiu Tudorache

    2009-07-01

    Full Text Available This paper deals with the finite element based optimal design of a wind energybased heater. The proposed device ensures the conversion of the wind kinetic energy intoheat by means of Joule effect of eddy currents induced in the wall of a tubular stator due tothe rotating magnetic field produced by rotor permanent magnets. The transientelectromagnetic field problem associated to the operation of the device is solved using a2D finite element approach based on vector potential formulation. A simplified method forthe 2D heat transfer analysis of the device is also proposed. The influence of stator wallmaterial and thickness, number of poles, the airgap thickness and the geometricalparameters of the permanent magnets is analyzed in the aim of optimizing the studiedheater.

  16. Constant delivery temperature solar water heater - an integrated approach

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, S. [C.A.S. Indian Institute of Technology, New Delhi (India); Kumar, N. [D.C.E. Muzaffarpur Institute of Technology, Bihar (India)

    1997-05-01

    An integrated model of a constant delivery temperature solar water heat-cum-active regenerative distillation system has been developed. The water used for the regenerative effect in the distiller of the proposed system is subsequently fed to the basin-cum-storage tank of the still through the heat exchanger (connected to the collector). The model varies the water mass flow rate in order to maintain a constant outlet temperature. With minor modifications in the solar water heater, the extra energy stored in the water mass due to non-utilization of capacity and/or non-linear utilization of capacity can be efficiently utilized for distillation purposes. In this process, the latent heat of vaporization is used for preheating the inlet water supply to the heat exchanger. The effect of insulation on maintaining the hot water temperature and distillate output is also presented. (Author)

  17. GPU-based parallel method of temperature field analysis in a floor heater with a controller

    Science.gov (United States)

    Forenc, Jaroslaw

    2016-06-01

    A parallel method enabling acceleration of the numerical analysis of the transient temperature field in an air floor heating system is presented in this paper. An initial-boundary value problem of the heater regulated by an on/off controller is formulated. The analogue model is discretized using the implicit finite difference method. The BiCGStab method is used to compute the obtained system of equations. A computer program implementing simultaneous computations on CPUand GPU(GPGPUtechnology) was developed. CUDA environment and linear algebra libraries (CUBLAS and CUSPARSE) are used by this program. The time of computations was reduced eight times in comparison with a program executed on the CPU only. Results of computations are presented in the form of time profiles and temperature field distributions. An influence of a model of the heat transfer coefficient on the simulation of the system operation was examined. The physical interpretation of obtained results is also presented.Results of computations were verified by comparing them with solutions obtained with the use of a commercial program - COMSOL Mutiphysics.

  18. Three-Dimensional Printable High-Temperature and High-Rate Heaters.

    Science.gov (United States)

    Yao, Yonggang; Fu, Kun Kelvin; Yan, Chaoyi; Dai, Jiaqi; Chen, Yanan; Wang, Yibo; Zhang, Bilun; Hitz, Emily; Hu, Liangbing

    2016-05-24

    High temperature heaters are ubiquitously used in materials synthesis and device processing. In this work, we developed three-dimensional (3D) printed reduced graphene oxide (RGO)-based heaters to function as high-performance thermal supply with high temperature and ultrafast heating rate. Compared with other heating sources, such as furnace, laser, and infrared radiation, the 3D printed heaters demonstrated in this work have the following distinct advantages: (1) the RGO based heater can operate at high temperature up to 3000 K because of using the high temperature-sustainable carbon material; (2) the heater temperature can be ramped up and down with extremely fast rates, up to ∼20 000 K/second; (3) heaters with different shapes can be directly printed with small sizes and onto different substrates to enable heating anywhere. The 3D printable RGO heaters can be applied to a wide range of nanomanufacturing when precise temperature control in time, placement, and the ramping rate are important.

  19. Assessing Consumer Values and the Supply-Chain Market for the Integrated Water Heater/Dehumidifier

    Energy Technology Data Exchange (ETDEWEB)

    Ashdown, BG

    2005-01-11

    This paper presents a case study of the potential market for the dual-service residential integrated water heater/dehumidifier (WHD). Its principal purpose is to evaluate the extent to which this integrated appliance might penetrate the residential market sector, given current market trends, producer and consumer attributes, and technical parameters. The report's secondary purpose is to gather background information leading to a generic framework for conducting market analyses of technologies. This framework can be used to assess market readiness as well as factor preferred product attributes into the design to drive consumer demand for this product. This study also supports analysis for prototype design. A full market analysis for potential commercialization should be conducted after prototype development. The integrated WHD is essentially a heat-pump water heater (HPWH) with components and controls that allow dedicated dehumidification. Adequate residential humidity control is a growing issue for newly constructed residential homes, which are insulated so well that mechanical ventilation may be necessary to meet fresh air requirements. Leveraging its successful experience with the energy-efficient design improvement for the residential HPWH, the Oak Ridge National Laboratory's (ORNL's) Engineering Science and Technology Division's (ESTD's) Building Equipment Group designed a water-heating appliance that combines HPWH efficiency with dedicated dehumidification. This integrated appliance could be a low-cost solution for dehumidification and efficient electric water heating. ORNL is partnering with Western Carolina University, Asheville-Buncombe Technical Community College, American Carolina Stamping Company, and Clemson University to develop this appliance and assess its market potential. For practical purposes, consumers are indifferent to how water is heated but are very interested in product attributes such as initial first cost

  20. Effects of heater location and heater size on the natural convection heat transfer in a square cavity using finite element method

    Energy Technology Data Exchange (ETDEWEB)

    Ngo, Ich Long; Byon, Chan [Yeungnam University, Gyeongsan (Korea, Republic of)

    2015-07-15

    Finite element method was used to investigate the effects of heater location and heater size on the natural convection heat transfer in a 2D square cavity heated partially or fully from below and cooled from above. Rayleigh number (5 X 10{sup 2} ≤ Ra ≤ 5X10{sup 5}), heater size (0.1 ≤ D/L ≤ 1.0), and heater location (0.1 ≤ x{sub h}/L ≤ 0.5) were considered. Numerical results indicated that the average Nusselt number (Nu{sub m}) increases as the heater size decreases. In addition, when x{sub h}/L is less than 0.4, Nu{sub m} increases as x{sub h}/L increases, and Num decreases again for a larger value of x{sub h}/L. However, this trend changes when Ra is less than 10{sup 4}, suggesting that Nu{sub m} attains its maximum value at the region close to the bottom surface center. This study aims to gain insight into the behaviors of natural convection in order to potentially improve internal natural convection heat transfer.

  1. Experimental study on flat plate air solar collector using a thin sand layer

    Science.gov (United States)

    Lati, Moukhtar; Boughali, Slimane; Bouguettaia, Hamza; Mennouche, Djamel; Bechki, Djamel

    2016-07-01

    A flat plate air solar collector was constructed in the laboratory of New and Renewable Energy in Arid Zones LENREZA, Ouargla University-South East Algeria. The absorber of the flat plate air solar collector was laminated with a thin layer of local sand. This acted as a thermal storage system (packed bed) with a collecting area of 2.15 m2 (0.86 m × 2.5 m). It was noticed that the solar heater integrated with the thermal storage material delivered comparatively higher temperatures; thus, giving a better efficiency than the air heater without the thermal storage system.

  2. Natural Convection of Nanofluids in a Square Enclosure with a Protruding Heater

    Directory of Open Access Journals (Sweden)

    J. Guiet

    2012-01-01

    Full Text Available This paper reports a numerical study on natural convection from a protruding heater located at the bottom of a square cavity filled with a copper-water nanofluid. The vertical walls of the cavity are cooled isothermally; the horizontal ones are adiabatic, and the heater is attached to the bottom wall. The heat source is assumed either to be isothermal or to have a constant heat flux. The effective viscosity and thermal conductivity of the nanofluid are modeled according to Brinkman and Patel, respectively. Numerical solutions of the full-governing equations, based on the lattice Boltzmann method, are obtained for a wide range of the governing parameters: the Rayleigh number, Ra; the Prandtl number, Pr; the geometrical parameters specifying the heater; the volume fraction of nanoparticles, Φ. For a particular geometry, it has been found that, for a given Ra, heat transfer is enhanced with increasing Φ, independently of the thermal boundary condition applied on the heater.

  3. A Simple Substrate Heater Device With Temperature Controller for Thin Film Preparation

    Directory of Open Access Journals (Sweden)

    G. Rendón

    2012-08-01

    Full Text Available A simple substrate heater and its temperature controller were designed and built in order to prepare thin films in a highvacuum deposition system. The substrate heater was elaborated with a glass-ceramic body and a molybdenum foilheater. The applied power and the temperature are regulated by a power controller board using a microcontrollerprogrammed with a proportional-integrative-derivative algorithm. The heater/controller system was tested in a highvacuum deposition system and the results of its characterization at 100, 200, 300 and 400 °C are presented. Avariation in temperature better than ± 0.5 °C was obtained for all the tested temperatures. An application of thesubstrate heater is demonstrated by evaporating gold thin films on heated glass substrates.

  4. Swift BAT Thermal Recovery After Loop Heat Pipe #0 Secondary Heater Controller Failure in October 2015

    Science.gov (United States)

    Choi, Michael K.

    2016-01-01

    The Swift BAT LHP #0 primary heater controller failed on March 31, 2010. It has been disabled. On October 31, 2015, the secondary heater controller of this LHP failed. On November 1, 2015, the LHP #0 CC temperature increased to as 18.6 C, despite that the secondary heater controller set point was 8.8 C. It caused the average DM XA1 temperature to increase to 25.9 C, which was 5 C warmer than nominal. As a result, the detectors became noisy. To solve this problem, the LHP #1 secondary heater controller set point was decreased in 0.5 C decrements to 2.2 C. The set-point decrease restored the average DM XA1 temperature to a nominal value of 19.7 C on November 21.

  5. Numerical Simulation of Induction Through-Heater in Dynamic Operation Mode

    Directory of Open Access Journals (Sweden)

    SCURTU Gheorghe Lucian

    2013-05-01

    Full Text Available The numeric model used in this paper is based on the finite element method and is aiming an inductive heating in volume of a cylindrical structure in a dynamic operation mode. Nowadays the inductionthrough-heaters are usually designed to provide the required characteristics in “quasi” steady-state operation mode mainly. However, in industrial practice the heaters can operate under various disturbances more than half of time, so the transient process playsignificant role in effectiveness and quality of the heating. Investigation of dynamic characteristics of the heaters in dynamic modes can be only done by numerical modeling based on special algorithms providing a time loop additionally to coupling betweenelectromagnetic and thermal analysis. Such numerical models have been developed and used for investigation of dynamic modes for heating billets. The results of numerical simulation can be used for design ofinduction through-heaters and improvement of their characteristics in dynamic operation modes.

  6. Energy-efficient tunable silicon photonic micro-resonator with graphene transparent nano-heaters

    CERN Document Server

    Yu, Longhai; Dai, Daoxin; He, Sailing

    2015-01-01

    Thermally-tuning silicon micro-cavities are versatile and beneficial elements in low-cost large-scale photonic integrated circuits (PICs). Traditional metal heaters used for thermal tuning in silicon micro-cavities usually need a thick SiO2 upper-cladding layer, which will introduce some disadvantages including low response speed, low heating efficiency, low achievable temperature and complicated fabrication processes. In this paper, we propose and experimentally demonstrate thermally-tuning silicon micro-disk resonators by introducing graphene transparent nano-heaters, which contacts the silicon core directly without any isolator layer. This makes the graphene transparent nano-heater potentially to have excellent performances in terms of the heating efficiency, the temporal response and the achievable temperature. It is also shown that the graphene nano-heater is convenient to be used in ultrasmall photonic integrated devices due to the single-atom thickness and excellent flexibility of graphene. Both experi...

  7. Analytical model for ring heater thermal compensation in the Advanced Laser Interferometer Gravitational-wave Observatory.

    Science.gov (United States)

    Ramette, Joshua; Kasprzack, Marie; Brooks, Aidan; Blair, Carl; Wang, Haoyu; Heintze, Matthew

    2016-04-01

    Advanced laser interferometer gravitational-wave detectors use high laser power to achieve design sensitivity. A small part of this power is absorbed in the interferometer cavity mirrors where it creates thermal lenses, causing aberrations in the main laser beam that must be minimized by the actuation of "ring heaters," which are additional heater elements that are aimed to reduce the temperature gradients in the mirrors. In this article we derive the first, to the best of our knowledge, analytical model of the temperature field generated by an ideal ring heater. We express the resulting optical aberration contribution to the main laser beam in this axisymmetric case. Used in conjunction with wavefront measurements, our model provides a more complete understanding of the thermal state of the cavity mirrors and will allow a more efficient use of the ring heaters in the Advanced Laser Interferometer Gravitational-wave Observatory.

  8. Self-regulating heater application to Shuttle/Centaur hydrazine fuel line thermal control

    Science.gov (United States)

    Unkrich, David B.

    1987-01-01

    The Shuttle/Centaur high energy upper stage vehicle thermal environments were more severe than previous Centaur vehicle thermal environments, creating need for a new hydrazine fuel line thermal control technique. Constant power heaters did not satisfy power dissipation requirements, because the power required to maintain fuel line thermal control during cold conditions exceeded the maximum power allowable during hot conditions. Therefore, a Raychem Thermolimit self-regulating heater was selected for this application, and was attached to the hydrazine fuel line with Kapton and aluminum foil tapes. Fuel line/heater thermal modeling and subsequent thermal vacuum chamber testing simulated heater thermal performance during all worst-case Shuttle/Centaur thermal environmental conditions. Fuel line temperatures were maintained between the 4C to 71C limits during all analytical and test cases. Finally, the thermal model predictions were correlated with the test data, thereby ensuring that the model would provide satisfactory predictions for future missions and/or vehicles.

  9. REFINED METHOD OF COMPUTING MODES OF OPERATING OF CAPACITY-TYPE SOLAR HEATERS OF

    Directory of Open Access Journals (Sweden)

    Ermuratschii Vl.V.

    2008-04-01

    Full Text Available The refined method procedure of thermal modes of solar heaters of water of the capacity type, based on use of an electro-thermal equivalent circuit and a method of central potentials is presented.

  10. Towards the Development of a Novel CNTs-based Flexible Mild Heater for Art Conservation

    Directory of Open Access Journals (Sweden)

    Tomas Markevicius

    2014-03-01

    tests performed on a series of prototypes of the designed heaters showed that the device was able to convey uniform heating on different working materials, thus proving to be effective for thermal consolidation.

  11. Temperature Profiles During Quenches in LHC Superconducting Dipole Magnets Protected by Quench Heaters

    CERN Document Server

    Maroussov, V; Siemko, A

    2000-01-01

    The efficiency of the magnet protection by quench heaters was studied using a novel method which derives the temperature profile in a superconducting magnet during a quench from measured voltage signals. In several Large Hadron Collider single aperture dipole models, temperature profiles and temperature gradients in the magnet coil have been evaluated in the case of protection by different sets of quench heaters and different powering and protection parameters. The influence of the insulation thickness between the quench heaters and the coil has also been considered. The results show clear correlation between the positions of quench heaters, magnet protection parameters and temperature profiles. This study allowed a better understanding of the quench process mechanisms and the efficiency assessment of the different protection schemes.

  12. Energetic Performances Study of an Integrated Collector Storage Solar Water Heater

    Directory of Open Access Journals (Sweden)

    O. Helal

    2010-01-01

    Full Text Available Problem statement: Although that the interest attributed to the solar energy remains relatively limited, we attend today to the conception of several installations using the sun as energy source among which we quote the solar water heater. Approach: A study of energetic performances was taken on an integrated collector/storage solar water heater made in the National School of Engineers of Gabes. This water heater is equipped with a concentration system containing a reflector composed of three parabolic branches favorating a better absorption of solar radiance. Results: The comparison between this system and two other systems of solar water heater, composed of a storage ball with asymmetrical CPC and symmetrical CPC, showed important energetic performances despite the simplicity and the little cost of the collector. Conclusion: Several improvements are necessary to increase the direct flow whilst decrease the thermal losses and therefore make the system simpler to be installed on the building roof.

  13. PREDICTION OF OPTIMUM ANGLE OF SOLAR WATER HEATER FOR COIMBATORE LOCATION

    OpenAIRE

    M. Sekar; DR M. SAKTHIVEL; O. MANIYARASU; N.ALAGU MURUGAN

    2013-01-01

    The objective of this work was to investigate ways to enhance the performance of solar water heater system to encourage many households using it. The integrated collector storage is the type of solar water heater that has retained its existence for well over a century. The flat absorber plate integrated collector storage type is a relatively recent addition. Being effective, low cost and simple to manufacture, their importance has been further enhanced by the recent upsurge in efforts to effe...

  14. Energy Savings and Breakeven Costs for Residential Heat Pump Water Heaters in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Maguire, Jeff [National Renewable Energy Lab. (NREL), Golden, CO (United States); Burch, Jay [National Renewable Energy Lab. (NREL), Golden, CO (United States); Merrigan, Tim [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ong, Sean [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2013-07-01

    Heat pump water heaters (HPWHs) have recently re-emerged in the U.S. residential water heating market and have the potential to provide homeowners with significant energy savings. However, there are questions as to the actual performance and energy savings potential of these units, in particular in regards to the heat pump's performance in unconditioned space and the impact of the heat pump on space heating and cooling loads when it is located in conditioned space. To help answer these questions, NREL performed simulations of a HPWH in both conditioned and unconditioned space at over 900 locations across the continental United States and Hawaii. Simulations included a Building America benchmark home so that any interaction between the HPWH and the home's HVAC equipment could be captured. Comparisons were performed to typical gas and electric water heaters to determine the energy savings potential and cost effectiveness of a HPWH relative to these technologies. HPWHs were found to have a significant source energy savings potential when replacing typical electric water heaters, but only saved source energy relative to gas water heater in the most favorable installation locations in the southern United States. When replacing an electric water heater, the HPWH is likely to break even in California, the southern United States, and parts of the northeast in most situations. However, the HPWH will only break even when replacing a gas water heater in a few southern states.

  15. Energy Savings and Breakeven Cost for Residential Heat Pump Water Heaters in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Maguire, J.; Burch, J.; Merrigan, T.; Ong, S.

    2013-07-01

    Heat pump water heaters (HPWHs) have recently reemerged in the U.S. residential water heating market and have the potential to provide homeowners with significant energy savings. However, there are questions as to the actual performance and energy savings potential of these units, in particular in regards to the heat pump's performance in unconditioned space and the impact of the heat pump on space heating and cooling loads when it is located in conditioned space. To help answer these questions, simulations were performed of a HPWH in both conditioned and unconditioned space at over 900 locations across the continental United States and Hawaii. Simulations included a Building America benchmark home so that any interaction between the HPWH and the home's HVAC equipment could be captured. Comparisons were performed to typical gas and electric water heaters to determine the energy savings potential and cost effectiveness of a HPWH relative to these technologies. HPWHs were found to have a significant source energy savings potential when replacing typical electric water heaters, but only saved source energy relative to gas water heater in the most favorable installation locations in the southern US. When replacing an electric water heater, the HPWH is likely to break even in California, the southern US, and parts of the northeast in most situations. However, the HPWH will only break even when replacing a gas water heater in a few southern states.

  16. PREDICTION OF OPTIMUM ANGLE OF SOLAR WATER HEATER FOR COIMBATORE LOCATION

    Directory of Open Access Journals (Sweden)

    M. SEKAR

    2013-04-01

    Full Text Available The objective of this work was to investigate ways to enhance the performance of solar water heater system to encourage many households using it. The integrated collector storage is the type of solar water heater that has retained its existence for well over a century. The flat absorber plate integrated collector storage type is a relatively recent addition. Being effective, low cost and simple to manufacture, their importance has been further enhanced by the recent upsurge in efforts to effectively tap renewable energy resources. Having different inclinations based on latitude, the design of flat plate heaters can benefit from extensive amount of research on the topic of natural convection in inclined cavities. The thermal performance of the heater is recorded experimentally at angles 0°–30° from horizontal, in 10° intervals. It was found that for any given constant value of heat flux, the performance of the heater is a strong function of the angle of inclination. The optimum configuration of the heater for Coimbatore location is also evaluated.

  17. Design, Construction, and Qualification of a Microscale Heater Array for Use in Boiling Heat Transfer

    Science.gov (United States)

    Rule, T. D.; Kim, J.; Kalkur, T. S.

    1998-01-01

    Boiling heat transfer is an efficient means of heat transfer because a large amount of heat can be removed from a surface using a relatively small temperature difference between the surface and the bulk liquid. However, the mechanisms that govern boiling heat transfer are not well understood. Measurements of wall temperature and heat flux near the wall would add to the database of knowledge which is necessary to understand the mechanisms of nucleate boiling. A heater array has been developed which contains 96 heater elements within a 2.5 mm square area. The temperature of each heater element is held constant by an electronic control system similar to a hot-wire anemometer. The voltage that is being applied to each heater element can be measured and digitized using a high-speed A/D converter, and this digital information can be compiled into a series of heat-flux maps. Information for up to 10,000 heat flux maps can be obtained each second. The heater control system, the A/D system and the heater array construction are described in detail. Results are presented which show that this is an effective method of measuring the local heat flux during nucleate and transition boiling. Heat flux maps are obtained for pool boiling in FC-72 on a horizontal surface. Local heat flux variations are shown to be three to six times larger than variations in the spatially averaged heat flux.

  18. Solar Biogas Digester with Built-In Reverse Absorber Heater

    Directory of Open Access Journals (Sweden)

    Khasan S. Karimov

    2013-01-01

    Full Text Available In this work the design, fabrication and investigation of a solar biogas digester with built-in RAH (Reverse Absorber Heater is presented. The maximum temperature (50 o C inside of the methane tank was taken as a main parameter at the design of the digester. Using energy balance equation for the case of a static mass of fluid being heated; the parameters of thermal insulation of the methane tank were counted. The biogas digester is consisting of methane tank with built-in solar RAH to utilize solar energy for the heating of the slurry prepared from the different organic wastes (dung, sewage, food wastes etc. The methane tank was filled up to 70% of volume by organic wastes of the GIK Institute sewage, firstly, and secondly, by sewage and cow dung as well. During three months (October-December, 2009 and two months (February-March, 2010 the digester was investigated. The solar irradiance incident to the absorber, slurry's temperature and ambient temperature were measured. It was found that using sewage only and sewage with cow dung the retention times was 4 weeks and two weeks respectively and biogas quantity produced was 0.4 and 8.0 m 3 respectively. In addition, biogas upgradation scheme for removal of carbon dioxide, hydrogen sulphide and water vapor from biogas and conversion of biogas energy conversion into electric power is also discussed.

  19. Light-weight radioisotope heater unit (LWRHU) impact tests

    Science.gov (United States)

    Reimus, M. A. H.; Rinehart, G. H.; Herrera, A.; Lopez, B.; Lynch, C.; Moniz, P.

    1998-01-01

    The light-weight radioisotope heater unit (LWRHU) is a 238PuO2-fueled heat source designed to provide one thermal watt in each of various locations on a spacecraft. Los Alamos National Laboratory designed, fabricated, and safety tested the LWRHU. The heat source consists of a hot-pressed 238PuO2 fuel pellet, a Pt-30Rh vented capsule, a pyrolytic graphite insulator, and a fineweave-pierced fabric graphite aeroshell assembly. To compare the performance of the LWRHUs fabricated for the Cassini mission with the performance of those fabricated for the Galileo mission, and to determine a failure threshold, two types of impact tests were conducted. A post-reentry impact test was performed on one of 180 flight-quality units produced for the Cassini mission and a series of sequential impact tests using simulant-fueled LWRHU capsules were conducted respectively. The results showed that deformation and fuel containment of the impacted Cassini LWRHU was similar to that of a previously tested Galileo LWRHU. Both units sustained minimal deformation of the aeroshell and fueled capsule; the fuel was entirely contained by the platinum capsule. Sequential impacting, in both end-on and side-on orientations, resulted in increased damage with each subsequent impact. Sequential impacting of the LWRHU appears to result in slightly greater damage than a single impact at the final impact velocity of 50 m/s.

  20. Heater induced thermal effects on the LTP dynamics

    CERN Document Server

    Gibert, Ferran; Lobo, Alberto; Díaz-Aguiló, Marc; Mateos, Ignacio; Karnesis, Nikolaos; Sanjuán, Josep; Gesa, Lluís; lloro, Ivan; Martín, Víctor

    2013-01-01

    The STOC (Science and Technology Operations Centre) simulator of the LPF (LISA PathFinder) mission is intended to provide a validation tool for the mission operations tele-commanding chain, as well as for a deeper understanding of the underlying physical processes happening in the LTP (LISA Technology Package). Amongst the different physical effects that will appear onboard, temperature fluctuations in the Electrode Housing (EH) could generate disturbances on the interferometer (IFO) readouts, therefore they must be known and controlled. In this article we report on the latest progress in the analysis at IEEC of the LTP response to thermal signals injected by means of heaters. More specifically, we determine the transfer functions relating heat input signals to forces on the Test Masses (TMs) in the LTP frequency band, from 1 mHz to 30 mHz. A complete thermal model of the entire LPF spacecraft plus payload, elaborated and maintained at European Space Technology Center (ESTEC), was used to obtain temperature d...

  1. Solar dryer with thermal storage and biomass-backup heater

    Energy Technology Data Exchange (ETDEWEB)

    Madhlopa, A. [Department of Physics and Biochemical Sciences, Malawi Polytechnic, P/Bag 303, Blantyre 3 (Malawi); Ngwalo, G. [Department of Mechanical Engineering, Malawi Polytechnic, P/Bag 303, Blantyre 3 (Malawi)

    2007-04-15

    An indirect type natural convection solar dryer with integrated collector-storage solar and biomass-backup heaters has been designed, constructed and evaluated. The major components of the dryer are biomass burner (with a rectangular duct and flue gas chimney), collector-storage thermal mass and drying chamber (with a conventional solar chimney). The thermal mass was placed in the top part of the biomass burner enclosure. The dryer was fabricated using simple materials, tools and skills, and it was tested in three modes of operation (solar, biomass and solar-biomass) by drying twelve batches of fresh pineapple (Ananas comosus), with each batch weighing about 20 kg. Meteorological conditions were monitored during the dehydration process. Moisture and vitamin C contents were determined in both fresh and dried samples. Results show that the thermal mass was capable of storing part of the absorbed solar energy and heat from the burner. It was possible to dry a batch of pineapples using solar energy only on clear days. Drying proceeded successfully even under unfavorable weather conditions in the solar-biomass mode of operation. In this operational mode, the dryer reduced the moisture content of pineapple slices from about 669 to 11% (db) and yielded a nutritious dried product. The average values of the final-day moisture-pickup efficiency were 15%, 11% and 13% in the solar, biomass and solar-biomass modes of operation respectively. It appears that the solar dryer is suitable for preservation of pineapples and other fresh foods. Further improvements to the system design are suggested. (author)

  2. Development of a comprehensive evaluation system for energy-saving operation of oilfield heaters%油田加热炉节能运行的综合评价系统开发

    Institute of Scientific and Technical Information of China (English)

    刘扬; 成庆林; 李秀娟

    2012-01-01

    基于Visual Basic语言和Access数据库管理工具开发了油田加热炉综合评价系统软件,在实现油田加热炉工艺参数计算的基础上,运用基于熵权的灰色关联分析理论对加热炉的节能运行进行综合评价.对某油田加热炉的应用实例分析结果表明:不同评价指标对加热炉运行的影响程度不同,其重要程度排序依次为:排烟温度、炉体外表面温度、空气系数、热效率;按照关联度数值大小可判别各台加热炉运行情况的优劣,其值越接近1,加热炉运行效果越优,否则为用能薄弱设备.由此为提高油田总体用能水平提供了更具操作性的依据.%Comprehensive evaluation system software of heater for oilfield use is developed based on Visual Basic Language and Access database management tool. This system can be used to assess the energy saving rate of the heater according to the gray correlation analysis theory of entropy weight by calculated process parameters of heaters. Case analysis indicates that different evaluation indicators have different influences on the energy saving rate of heater, and the priority sequence of which lists as follows, exhaust temperature, outside surface temperature of heater, air coefficient and thermal efficiency. The energy saving rate of each heater can be confirmed in accordance with the magnitude of correlativity. If the value is closer to 1, the heater runs better, otherwise it is considered as weak equipment. Thus a more operational basis is provided for the oilfield to improve its overall energy consumption level.

  3. Recycle Effect on Device Performance of Wire Mesh Packed Double-Pass Solar Air Heaters

    Directory of Open Access Journals (Sweden)

    Chii-Dong Ho

    2014-11-01

    Full Text Available A new device for inserting an absorber plate to divide a flat-plate channel into two subchannels to conduct double-pass wire mesh packed operations was developed. The proposed wire mesh packed device improves the heat transfer efficiency substantially as compared that to flat-plate single-pass and double-pass operations using the same working dimensions, and the improvement of device performance was investigated experimentally and theoretically. Good agreement between the theoretical prediction and the measured values from the experimental results was achieved. Considerable heat transfer improvement was obtained employing wire mesh packed double-pass operations under the absorber plate with external recycle. The influences of recycle ratio on the heat transfer efficiency and the power consumption increase were also discussed.

  4. Effect of Uniformly and Nonuniformly Coated Al2O3 Nanoparticles over Glass Tube Heater on Pool Boiling

    Directory of Open Access Journals (Sweden)

    Nitin Doifode

    2016-01-01

    Full Text Available Effect of uniformly and nonuniformly coated Al2O3 nanoparticles over plain glass tube heater on pool boiling heat transfer was studied experimentally. A borosilicate glass tube coated with Al2O3 nanoparticle was used as test heater. The boiling behaviour was studied by using high speed camera. Result obtained for pool boiling shows enhancement in heat transfer for nanoparticle coated surface heater and compared with plain glass tube heater. Also heat transfer coefficient for nonuniformly coated nanoparticles was studied and compared with uniformly coated and plain glass tube. Coating effect of nanoparticles over glass tube increases its surface roughness and thereby creates more nucleation sites.

  5. Development of an Accurate Feed-Forward Temperature Control Tankless Water Heater

    Energy Technology Data Exchange (ETDEWEB)

    David Yuill

    2008-06-30

    The following document is the final report for DE-FC26-05NT42327: Development of an Accurate Feed-Forward Temperature Control Tankless Water Heater. This work was carried out under a cooperative agreement from the Department of Energy's National Energy Technology Laboratory, with additional funding from Keltech, Inc. The objective of the project was to improve the temperature control performance of an electric tankless water heater (TWH). The reason for doing this is to minimize or eliminate one of the barriers to wider adoption of the TWH. TWH use less energy than typical (storage) water heaters because of the elimination of standby losses, so wider adoption will lead to reduced energy consumption. The project was carried out by Building Solutions, Inc. (BSI), a small business based in Omaha, Nebraska. BSI partnered with Keltech, Inc., a manufacturer of electric tankless water heaters based in Delton, Michigan. Additional work was carried out by the University of Nebraska and Mike Coward. A background study revealed several advantages and disadvantages to TWH. Besides using less energy than storage heaters, TWH provide an endless supply of hot water, have a longer life, use less floor space, can be used at point-of-use, and are suitable as boosters to enable alternative water heating technologies, such as solar or heat-pump water heaters. Their disadvantages are their higher cost, large instantaneous power requirement, and poor temperature control. A test method was developed to quantify performance under a representative range of disturbances to flow rate and inlet temperature. A device capable of conducting this test was designed and built. Some heaters currently on the market were tested, and were found to perform quite poorly. A new controller was designed using model predictive control (MPC). This control method required an accurate dynamic model to be created and required significant tuning to the controller before good control was achieved. The MPC

  6. Local Convective Heat Transfer from Small Heaters to Impinging Submerged Axisymmetric Jets of Seven Coolants with Prandtl Number Ranging from 0.7 to 348

    Institute of Scientific and Technical Information of China (English)

    H.Sun; C.F.Ma; 等

    1997-01-01

    Using seven working fluids,a systematic experimental study was performed to investigate the local convective heat transfer from vertical heaters to impinging circular submerged jets in the range of Reynolds number between 1.17×102 and 3.69×104 with the emphasis placed on the examination of Prandtl number dependence.Heat transfer coefficients at the stagnation point were collected and correlated with the plate held within and beyond the potential core.Radial distribution of the local heat transfer coefficient was measured with five test liquids.Based on the measured profiles of the local heat transfer,a correlation was developed to cover the entire range of the adial distance.Basides the present data,the correlations developed in this work were also compared with a large quantity of available data of circular air jets.General agreement was observed between the air data and the correlations.

  7. Temperature optimization of an electric heater by emissivity variation of heating elements

    Directory of Open Access Journals (Sweden)

    Cédric Hemmer

    2014-11-01

    Full Text Available This note addresses an industrial application concerning the way to optimize the surface temperature of commercial electrical heater. The aim of this paper is to reduce the temperature on accessible surfaces and electrical heater in order to respect the European standards and quality criteria imposed by the manufacturer. This target must be achieved by changing only the emissivity distribution of the electric heater components. A numerical study of the natural convection flow coupled with radiation is carried out in a heated room with an electric heater. The physical model includes the transport equations of mass, momentum, energy and radiative transfer which are solved numerically. Thermo-physical properties of the fluid are assumed to be dependent of the temperature. The numerical simulations are carried out for a two-dimensional, steady and turbulent flow using the finite volume approach. Results showed the influence of emissivity distribution of the electric heater components. The reducing of the heating foil emissivity allowed to decrease the radiative contribution on the foil and its temperature.

  8. Accelerated Life Structural Benchmark Testing for a Stirling Convertor Heater Head

    Science.gov (United States)

    Krause, David L.; Kantzos, Pete T.

    2006-01-01

    For proposed long-duration NASA Space Science missions, the Department of Energy, Lockheed Martin, Infinia Corporation, and NASA Glenn Research Center are developing a high-efficiency, 110 W Stirling Radioisotope Generator (SRG110). A structurally significant limit state for the SRG110 heater head component is creep deformation induced at high material temperature and low stress level. Conventional investigations of creep behavior adequately rely on experimental results from uniaxial creep specimens, and a wealth of creep data is available for the Inconel 718 material of construction. However, the specified atypical thin heater head material is fine-grained with a heat treatment that limits precipitate growth, and little creep property data for this microstructure is available in the literature. In addition, the geometry and loading conditions apply a multiaxial stress state on the component, far from the conditions of uniaxial testing. For these reasons, an extensive experimental investigation is ongoing to aid in accurately assessing the durability of the SRG110 heater head. This investigation supplements uniaxial creep testing with pneumatic testing of heater head-like pressure vessels at design temperature with stress levels ranging from approximately the design stress to several times that. This paper presents experimental results, post-test microstructural analyses, and conclusions for four higher-stress, accelerated life tests. Analysts are using these results to calibrate deterministic and probabilistic analytical creep models of the SRG110 heater head.

  9. A modernized high-pressure heater protection system for nuclear and thermal power stations

    Science.gov (United States)

    Svyatkin, F. A.; Trifonov, N. N.; Ukhanova, M. G.; Tren'kin, V. B.; Koltunov, V. A.; Borovkov, A. I.; Klyavin, O. I.

    2013-09-01

    Experience gained from operation of high-pressure heaters and their protection systems serving to exclude ingress of water into the turbine is analyzed. A formula for determining the time for which the high-pressure heater shell steam space is filled when a rupture of tubes in it occurs is analyzed, and conclusions regarding the high-pressure heater design most advisable from this point of view are drawn. A typical structure of protection from increase of water level in the shell of high-pressure heaters used in domestically produced turbines for thermal and nuclear power stations is described, and examples illustrating this structure are given. Shortcomings of components used in the existing protection systems that may lead to an accident at the power station are considered. A modernized protection system intended to exclude the above-mentioned shortcomings was developed at the NPO Central Boiler-Turbine Institute and ZioMAR Engineering Company, and the design solutions used in this system are described. A mathematical model of the protection system's main elements (the admission and check valves) has been developed with participation of specialists from the St. Petersburg Polytechnic University, and a numerical investigation of these elements is carried out. The design version of surge tanks developed by specialists of the Central Boiler-Turbine Institute for excluding false operation of the high-pressure heater protection system is proposed.

  10. Development of the robot for pressurizer electric heater inspection and repairing

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Seung Ho; Kim, Seung Ho; Su, Yong Chil

    1998-01-01

    In this study a robot system has been developed for inspection and maintenance of the pressurizer and the rod heater. The developed robot system consists of four parts: two links, a support frame, a movable gripper, and a controller box. The robot is attached on the support frame, which is attached at the man-way flange of the pressurizer such that the robot is positioned inside pressurizer. To access arbitrary heater, at first two links horizontally rotate, and then the gripper suspended by two steel wires moves up and down by turing wire drum because the rod heaters are located about 8 meters under the robot and are arranged in two circular rows. The robot must be designed under several constraint such as its weight and collision with pressurizer wall or spray nozzle because the robot is positioned and moves inside the pressurizer. To verify that the designed robot is free from collision during installation procedure and it can access any desired rod heater, it is simulated by 3-dimensional graphic software (RobCAD). For evaluating stress of the support frame finite element analysis is performed by using the ANSYS code. For gripping the rod heater the passive self-locking mechanism is adopted, which is made up three balls and springs. Because the mechanism is very simple, it is very hardly defected than that adopted motor. (author). 11 refs., 8 tabs., 13 figs

  11. Accelerator Magnet Quench Heater Technology and Quality Control Tests for the LHC High Luminosity Upgrade

    CERN Document Server

    Meuter, Florian

    The High Luminosity upgrade of the Large Hadron Collider (HL-LHC) foresees the installation of new superconducting Nb3Sn magnets. For the protection of these magnets, quench heaters are placed on the magnet coils. The quench heater circuits are chemically etched from a stainless steel foil that is glued onto a flexible Polyimide film, using flexible printed circuit production technology. Approximately 500 quench heaters with a total length of about 3000 m are needed for the HL-LHC magnets. In order to keep the heater circuit electrical resistance in acceptable limits, an approximately 10 µm-thick Cu coating is applied onto the steel foil. The quality of this Cu coating has been found critical in the quench heater production. The work described in this thesis focuses on the characterisation of Cu coatings produced by electrolytic deposition, sputtering and electron beam evaporation. The quality of the Cu coatings from different manufacturers has been assessed for instance by ambient temperature electrical res...

  12. Fuel-Flexible Combustion System for Refinery and Chemical Plant Process Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Benson, Charles; Wilson, Robert

    2014-04-30

    air pollutant emissions. In Phase 3, the team retrofitted three fuel-flexible burners into a fired heater at a Shell plant and demonstrated the project’s technology over a 6-month period. The project burners performed well during this period. They remain in commercial service at the Shell plant. Through this work, an improved understanding of flame stabilization mechanisms was gained. Also, methods for accommodating a wide range of fuel compositions were developed. This knowledge facilitated the commercialization of a new generation of burners that are suitable for the fuels of the future.

  13. Preliminary Modeling, Testing, and Analysis of a Gas Tankless Water Heater: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Burch, J.; Hoeschele, M.; Springer, D.; Rudd, A.

    2008-05-01

    Today's gas tankless water heaters offer significant energy savings over conventional gas storage tank water heaters, but savings depends on the draw pattern. A one-node model incorporating heat exchanger mass is used to address this and other issues. Key model parameters are determined from least-squares regression on short-term data, including burner efficiency, thermal capacitance, and thermal loss coefficient. The calibrated model agrees with data to ~5% on Qgas, with temperature RMS deviation of ~4..deg..C. Efficiency with a standard realistic draw is 71%, compared to 81% predicted from standard energy-factors. Adding a small tank controlled by the tankless heater solves issues of oscillations with solar pre-heat, low-flow and hot-water-delay issues. Future work includes model refinements and developing optimal data protocols for model parameter extraction.

  14. Development of Industrially Produced Composite Quench Heaters for the LHC Superconducting Lattice Magnets

    CERN Document Server

    Szeless, Balázs; Calvone, F

    1996-01-01

    The quench heaters are vital elements for the protection of the LHC superconducting lattice magnets in the case of resistive transitions of the conductor. The basic concept of magnet protection and technical solutions are briefly presented. The quench heater consists of partially copper clad stainless steel strips sandwiched in between electric insulating carrier foils with electrical and mechanical properties such as to withstand high voltages, low temperatures, pressures and ionizing radiation. Testing of some commercial available electric insulation foils, polyimide (PI), polyetheretherketon (PEEK) and polyarylate (PA) and combinations of adhesive systems which are suitable for industrial processing are described. Possible industrial methods for series production for some 80 km of these composite quench heaters are indicated.

  15. A novel domestic electric water heater model for a multi-objective demand side management program

    Energy Technology Data Exchange (ETDEWEB)

    Paull, Liam; Li, Howard; Chang, Liuchen [University of New Brunswick, Department of Electrical Engineering, Fredericton, NB (Canada)

    2010-12-15

    This paper presents a novel domestic hot water heater model to be used in a multi-objective demand side management program. The model incorporates both the thermal losses and the water usage to determine the temperature of the water in the tank. Water heater loads are extracted from household load data and then used to determine the household water usage patterns. The benefits of the model are: (1) the on/off state of the water heater and temperature of the water in the tank can be accurately predicted, and (2) it enables the development of water usage profiles so that users can be classified based on usage behaviour. As a result, the amount of ancillary services and peak shaving that can be achieved are accurately predictable and can be maximized without adversely affecting users. (author)

  16. Study on Ag mesh/conductive oxide hybrid transparent electrode for film heaters

    Science.gov (United States)

    Kwon, Namyong; Kim, Kyohyeok; Heo, Jinhee; Yi, Insook; Chung, Ilsub

    2014-07-01

    Ag mesh-indium tin oxide (ITO) hybrid transparent conductive films were fabricated and evaluated for use in film heaters. PS monolayer templates were prepared using highly mono-dispersed PS spheres (11.2 μm) obtained by a filtering process with micro-sieves. At first, three Ag meshes with different sheet resistances (20, 100, and 300 Ω sq-1) and transmittances (70, 73, and 76%) were evaluated for film heaters in terms of voltage and long-term stability. Subsequently, in an effort to obtain better transmittance, Ag mesh-ITO hybrid heaters were fabricated utilizing finite ITO depositions. At the optimised ITO thickness (15 nm), the sheet resistance and the transmittance were 300 Ω sq-1 and 88%, respectively, which indicates that this material is a good potential candidate for an efficient defroster in vehicles.

  17. Design of high-pressure direct contact heater for promising power supply units: Experimental substantiation

    Science.gov (United States)

    Somova, E. V.; Shvarts, A. L.; Turkin, A. V.

    2016-11-01

    The results of experimental studies of superheated steam condensation on feed water jets in a highpressure, direct-contact heat exchanger are presented. Direct contact feed water heater (DCFWH) can be used in a dual-flow diagram of a steam-power unit with ultrasupercritical steam parameters (35 MPa, 700/720°C). The direct contact feed water heater is included in the flow diagram of the II circuit in a promising power unit; it provides feed water heating to 340°C in all maintenance and emergency operation modes of the unit. The reliability of the high-pressure direct contact heater operation in this flow diagram is of major importance in relation to the danger of lead solidification in the tube space of the steam generator. Technical requirements to the design of the high-pressure direct contact heater for increasing the heat exchange efficiency are formulated based on the results of earlier studies with steam-water mixture as the heating medium. The results of studies of superheated steam condensation on jets presented in this study testify that feed water is additionally heated to the required temperature at the output of the installation. The influence of initial feed water parameters (outflow velocity and temperature) on the jet heating length is elucidated. The numerical approximation of the experimental data for determination of the jet heating length in the nominal and partial power unit loads is obtained. The results of the calculations are used to simplify the design of the water-supplying element for the direct contact feed water heater. The proposed design of direct contact feed water heater is characterized by simplicity and low metal intensity, which provides the installation reliability at the considered pressure level due to the minimum number of structural elements.

  18. Particle impaction efficiency and size distribution in a MSWI super heater tube bundle

    CERN Document Server

    Haugen, Nils Erland L; Bugge, Mette; Warnecke, Ragnar; Weghaus, Martin

    2010-01-01

    Particle impaction in the super heater geometry found in the municipal solid waste incinerator (MSWI) of GKS in Schweinfurt, Germany, has been investigated. By using direct numerical simulations for the fluid flow, inertial particles coupled to the fluid through the classical Stokes' drag law have been tracked. Focus has been on the effect of flow velocity, and it is shown that decreasing the flow velocity will drastically decrease the impaction efficiency for some particle radii. Finally particle size distribution measurements are presented and used to find quantitative mass fluxes both on the front and the back side of the tubes in the super heater tube bundle.

  19. Enhanced Heat Transfer Tubes for Absorber of Absorption Chiller/Heater

    Science.gov (United States)

    Furukawa, Masahiro; Sasaki, Naoe; Kaneko, Toshiyuki; Nosetani, Tadashi

    For the purpose of development of high performance absorption chiller/heater utilizing lithium bromide aqueous solution as working fluid, it is the most effective to improve the performance of absorber with the largest heat transfer area of the four heat exchangers. This paper introduces two kinds of double fluted tubes for the absorber of absorption chiller/heater. Arm tube and floral tube have about 40% higter heat transfer performance than the plain tube conventionally used in absorber. The former is manufactured by double drawbench process, while the latter by single drawbench process. Therefore, floral tube is expected to realize both high heat transfer perfoemance and low cost.

  20. Light Weight Radioisotope Heater Unit (LWRHU) production for the Galileo mission

    Science.gov (United States)

    Rinehart, Gary H.

    The Light Weight Radioisotope Heater Unit (LWRHU) is a (Pu-238)O2-fueled heat source designed to provide a thermal watt of power for space missions. The LWRHU will be used to maintain the temperature of various components on the spacecraft at the required level. The heat source consists of a (Pu-238)O2-fuel pellet, a Pt-30 pct Rh capsule, a pyrolytic graphite insulator, and a woven graphite aeroshell assembly. Los Alamos National Laboratory has fabricated 134 heater units which will be used on the Galileo mission.

  1. Rate of heat transfer in polypropylene tubes in solar water heaters

    Energy Technology Data Exchange (ETDEWEB)

    Razavi, J.; Mahmoodi, M. [Sharif University of Technology, Tehran (Iran). Chemical Engineering Dept.; Riazi, M.R. [Kuwait Univ., Safat (Kuwait). Chemical Engineering Dept.

    2003-06-01

    A heat transfer rate was determined for polypropylene tubes in solar water heaters for the Reynolds number range 800-5600. Experiments were conducted in ambient temperatures of 34 to 37 {sup o}C. Data were correlated in the form of Nusselt numbers as: Nu=0.0015 Re{sup 0.75}Pr{sup 1/3} with correlation coefficient of 0.95. Such data can be used to predict heat transfer rates in a polypropylene solar heater in Tehran where the experiments were performed. An application of the results is shown in an example. (author)

  2. Feed-water heaters alternative design comparison; Comparacion de disenos alternativos de calentadores

    Energy Technology Data Exchange (ETDEWEB)

    Torres Toledano, Gerardo [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1988-12-31

    A procedure is presented for the alternative design comparison of feed water heaters, based in the failure records of damaged tubes during operation. The procedure is used for cases in which non-continuous or random inspections are made to the feed-water heaters. [Espanol] Se presenta un procedimiento para comparar disenos alternativos de calentadores, basandose en los registros de fallas de los tubos rotos acumuladas durante su operacion. El procedimiento se emplea para casos en los que se realizan inspecciones a los calentadores no continuas, ya sea periodicas o al azar.

  3. Experimental studies on PCM filled Flat Plate Solar Water Heater without and with Fresnel lens glazing

    Directory of Open Access Journals (Sweden)

    R. Sivakumar

    2016-07-01

    Full Text Available Flat Plate Solar Water Heater (FPSWH is commonly used to harvest solar energy. Solar concentration techniques help to achieve higher temperatures of energy. The aim of this article is to compare the performance of a Fresnel lens glazed Flat Plate Solar Water Heater with Phase Change Material (PCM with that provided with an ordinary glazing. The effect of solar concentration using Fresnel lens on energy storage in PCM and heat gained by water are studied and compared with that having an ordinary glazing. Experiments showed 47% improvements in the heat gained by water.

  4. Experimental comparison of alternative convection suppression arrangements for concentrating integral collector storage solar water heaters

    Energy Technology Data Exchange (ETDEWEB)

    Smyth, M.; McGarrigle, P.; Eames, P.C. [Ulster Univ., School of the Built Environment, Newtownabbey, Northern Ireland (United Kingdom); Norton, B. [Dublin Inst. of Technology, Dublin (Ireland)

    2005-02-01

    An experimental investigation of an inverted absorber integrated collector storage solar water heater mounted in the tertiary cavity of a compound parabolic concentrator with a secondary cylindrical reflector has been performed under simulated solar conditions. The solar water heaters performance was determined with the aperture parallel to the simulator for a range of transparent baffles positioned at different locations within the collector cavity. Results indicate that glass baffles located at the upper portion of the exit aperture of the CPC can reduce thermal losses through convection suppression without significantly increasing optical losses. (Author)

  5. 41 CFR 102-74.190 - Are portable heaters, fans and other such devices allowed in Government-controlled facilities?

    Science.gov (United States)

    2010-07-01

    ... § 102-74.190 Are portable heaters, fans and other such devices allowed in Government-controlled facilities? Federal agencies are prohibited from operating portable heaters, fans, and other such devices in... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Are portable...

  6. PERFORMANCE DETERIORATION OF THERMOSIPHON SOLAR FLAT PLATE WATER HEATER DUE TO SCALING

    Directory of Open Access Journals (Sweden)

    arunachala umesh chandavar

    2011-12-01

    Full Text Available 0 0 1 340 1943 International Islamic University 16 4 2279 14.0 Normal 0 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Times New Roman";} The performance of Flat plate Solar Water Heater deteriorates within five to twelve years of their installation due to factors related to manufacturing, operating conditions, lack of maintenance etc. Especially, problem due to scaling is significant as it is based on quality of water used. The remaining factors are system dependent and could be overcome by quality production. Software is developed by incorporating Hottel Whillier Bliss (H-W-B equation to ascertain the effect of scaling on system efficiency in case of thermosiphon system. In case of clean thermosiphon system, the instantaneous efficiency calculated at 1000 W/m2 radiation is 72 % and it drops to 46 % for 3.7 mm scale thickness. The mass flow rate is reduced by 90 % for 3.7 mm scale thickness. Whereas, the average temperature drop of water in the tank is not critical due to considerable heat content in water under severe scaled condition.  But practically in case of major scale growth, some of the risers are likely to get blocked completely which leads to negligible temperature rise in the tank. ABSTRAK: Prestasi plat rata pemanas air suria merosot selepas lima hingga dua belas tahun  pemasangannya disebabkan faktor-faktor yang berkaitan dengan pembuatannya, cara kendaliannya, kurangnya penyelenggaraan dan sebagainya.  Terutama sekali, masalah disebabkan scaling (tembunan endapan mineral perlu diambil berat kerana ianya bergantung kepada kualiti air yang digunakan. Faktor-faktor selebihya bersandarkan sistem dan ia

  7. Heat Pump Water Heater Technology: Experiences of Residential Consumers and Utilities

    Energy Technology Data Exchange (ETDEWEB)

    Ashdown, BG

    2004-08-04

    This paper presents a case study of the residential heat pump water heater (HPWH) market. Its principal purpose is to evaluate the extent to which the HPWH will penetrate the residential market sector, given current market trends, producer and consumer attributes, and technical parameters. The report's secondary purpose is to gather background information leading to a generic framework for conducting market analyses of technologies. This framework can be used to compare readiness and to factor attributes of market demand back into product design. This study is a rapid prototype analysis rather than a detailed case analysis. For this reason, primary data collection was limited and reliance on secondary sources was extensive. Despite having met its technical goals and having been on the market for twenty years, the HPWH has had virtually no impact on contributing to the nation's water heating. In some cases, HPWH reliability and quality control are well below market expectations, and early units developed a reputation for unreliability, especially when measured against conventional water heaters. In addition to reliability problems, first costs of HPWH units can be three to five times higher than conventional units. Without a solid, well-managed business plan, most consumers will not be drawn to this product. This is unfortunate. Despite its higher first costs, efficiency of an HPWH is double that of a conventional water heater. The HPWH also offers an attractive payback period of two to five years, depending on hot water usage. On a strict life-cycle basis it supplies hot water very cost effectively. Water heating accounts for 17% of the nation's residential consumption of electricity (see chart at left)--water heating is second only to space heating in total residential energy use. Simple arithmetic suggests that this figure could be reduced to the extent HPWH technology displaces conventional water heating. In addition, the HPWH offers other

  8. System and method for air temperature control in an oxygen transport membrane based reactor

    Science.gov (United States)

    Kelly, Sean M

    2016-09-27

    A system and method for air temperature control in an oxygen transport membrane based reactor is provided. The system and method involves introducing a specific quantity of cooling air or trim air in between stages in a multistage oxygen transport membrane based reactor or furnace to maintain generally consistent surface temperatures of the oxygen transport membrane elements and associated reactors. The associated reactors may include reforming reactors, boilers or process gas heaters.

  9. An International Survey of Electric Storage Tank Water Heater Efficiency and Standards

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Alissa; Lutz, James; McNeil, Michael A.; Covary, Theo

    2013-11-13

    Water heating is a main consumer of energy in households, especially in temperate and cold climates. In South Africa, where hot water is typically provided by electric resistance storage tank water heaters (geysers), water heating energy consumption exceeds cooking, refrigeration, and lighting to be the most consumptive single electric appliance in the home. A recent analysis for the Department of Trade and Industry (DTI) performed by the authors estimated that standing losses from electric geysers contributed over 1,000 kWh to the annual electricity bill for South African households that used them. In order to reduce this burden, the South African government is currently pursuing a programme of Energy Efficiency Standards and Labelling (EES&L) for electric appliances, including geysers. In addition, Eskom has a history of promoting heat pump water heaters (HPWH) through incentive programs, which can further reduce energy consumption. This paper provides a survey of international electric storage water heater test procedures and efficiency metrics which can serve as a reference for comparison with proposed geyser standards and ratings in South Africa. Additionally it provides a sample of efficiency technologies employed to improve the efficiency of electric storage water heaters, and outlines programs to promote adoption of improved efficiency. Finally, it surveys current programs used to promote HPWH and considers the potential for this technology to address peak demand more effectively than reduction of standby losses alone

  10. A new regulation for terrace heaters; ERP: parasols chauffants et cuisson mobile

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2003-09-01

    After a year of discussions, the terrace heaters are from now on entirely authorized. They have indeed just coming to be included in a clear and explicit way in the 'safety rule against the fire and panic risks in the establishments receiving the public. Some precise details are given too for the use of LPG in movable kitchens (exhibition). (O.M.)

  11. Increasing reliability of system water heaters for steam-turbine installations at the design stage

    Science.gov (United States)

    Brezgin, V. I.; Brodov, Yu. M.; Brezgin, D. V.

    2015-12-01

    A system for designing water heaters of steam-turbine installations based on uniting standards, reference information, and some numerical procedures with design procedures via wide use of parameterization is considered. The developed design system is based on extensive application of modern information technologies.

  12. Solar hot water systems for the southeastern United States: principles and construction of breadbox water heaters

    Energy Technology Data Exchange (ETDEWEB)

    None

    1983-02-01

    The use of solar energy to provide hot water is among the easier solar technologies for homeowners to utilize. In the Southeastern United States, because of the mild climate and abundant sunshine, solar energy can be harnessed to provide a household's hot water needs during the non-freezing weather period mid-April and mid-October. This workbook contains detailed plans for building breadbox solar water heaters that can provide up to 65% of your hot water needs during warm weather. If fuel costs continue to rise, the annual savings obtained from a solar water heater will grow dramatically. The designs in this workbook use readily available materials and the construction costs are low. Although these designs may not be as efficient as some commercially available systems, most of a household's hot water needs can be met with them. The description of the breadbox water heater and other types of solar systems will help you make an informed decision between constructing a solar water heater or purchasing one. This workbook is intended for use in the southeastern United States and the designs may not be suitable for use in colder climates.

  13. Microbunching Instability Effect Studies and Laser Heater Optimization for the SPARX FEL Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Vaccarezza, C.; Chiadroni, E.; Ferrario, M.; Giannessi, L.; Quattromini, M.; Ronsivalle, C.; Venturini, C.; Migliorati, M.; Dattoli, G.

    2010-05-23

    The effects of microbunching instability for the SPARX accelerator have been analyzed by means of numerical simulations. The laser heater counteracting action has been addressed in order to optimize the parameters of the compression system, either hybrid RF plus magnetic chicane or only magnetic, and possibly enhance the FEL performance.

  14. Local Adaptive Control of Solar Photovoltaics and Electric Water Heaters for Real-time Grid Support

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad; Mendaza, Iker Diaz de Cerio; Bak-Jensen, Birgitte

    2016-01-01

    , such as electric vehicles, electric water heaters (EWHs) etc. An adaptive control using only local measurements for the EWHs and PVs is proposed in this study to alleviate OV as well as UV issues. The adaptive control is designed such that it monitors the voltage at the point of connection and adjusts active...

  15. Measure Guideline. Heat Pump Water Heaters in New and Existing Homes

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, Carl [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Puttagunta, Srikanth [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Owens, Douglas [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States)

    2012-02-01

    This Building America Measure Guideline is intended for builders, contractors, homeowners, and policy-makers. This document is intended to explore the issues surrounding heat pump water heaters (HPWHs) to ensure that homeowners and contractors have the tools needed to appropriately and efficiently install HPWHs

  16. Regional Variation in Residential Heat Pump Water Heater Performance in the U.S.

    Energy Technology Data Exchange (ETDEWEB)

    Maguire, Jeff [National Renewable Energy Lab. (NREL), Golden, CO (United States); Burch, Jay [National Renewable Energy Lab. (NREL), Golden, CO (United States); Merrigan, Tim [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ong, Sean [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-01-01

    Residential heat pump water heaters (HPWHs) have recently re-emerged on the U.S. market, and they have the potential to provide homeowners significant cost and energy savings. However, actual in use performance of a HPWH will vary significantly with climate, installation location, HVAC equipment, and hot water use. To determine the actual energy consumption of a HPWH in different U.S. regions, annual simulations of both 50 and 80 gallon HPWHs as well as a standard electric water heater were performed for over 900 locations across the United States. The simulations included a benchmark home to take into account interactions between the space conditioning equipment and the HPWH and a realistic hot water draw profile. It was found that the HPWH will always save some source energy when compared to a standard electric resistance water heater, although savings varies widely with location. In addition to looking at source energy savings, the breakeven cost (the net installed cost a HPWH would have to have to be a cost neutral replacement for a standard water heater) was also examined. The highest breakeven costs were seen in cases with high energy savings, such as the southeastern U.S., or high energy costs, such as New England and California. While the breakeven cost is higher for 80 gallon units than 50 gallon units, the higher net installed costs of an 80 gallon unit lead to the 50 gallon HPWHs being more likely to be cost effective.

  17. Regional Variation in Residential Heat Pump Water Heater Performance in the U.S.: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Maguire, J.; Burch, J.; Merrigan, T.; Ong, S.

    2014-01-01

    Residential heat pump water heaters (HPWHs) have recently reemerged on the U.S. market. These units have the potential to provide homeowners significant cost and energy savings. However, actual in use performance of a HPWH will vary significantly with climate, installation location, HVAC equipment, and hot water use. To determine what actual in use energy consumption of a HPWH may be in different regions of the U.S., annual simulations of both 50 and 80 gallon HPWHs as well as a standard electric water heater were performed for over 900 locations across the U.S. The simulations included a benchmark home to take into account interactions between the space conditioning equipment and the HPWH and a realistic hot water draw profile. It was found that the HPWH will always save some source energy when compared to a standard electric resistance water heater, although savings varies widely with location. In addition to looking at source energy savings, the breakeven cost (the net installed cost a HPWH would have to have to be a cost neutral replacement for a standard water heater) was also examined. The highest breakeven costs were seen in cases with high energy savings, such as the southeastern U.S., or high energy costs, such as New England and California. While the breakeven cost is higher for 80 gallon units than 50 gallon units, the higher net installed costs of an 80 gallon unit lead to the 50 gallon HPWHs being more likely to be cost effective.

  18. 16 CFR Appendix D5 to Part 305 - Water Heaters-Heat Pump

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Water Heaters-Heat Pump D5 Appendix D5 to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULE... Appendix D5 to Part 305—Water Heaters—Heat Pump Range Information CAPACITY FIRST HOUR RATING Range...

  19. Application for the On-line Isotope Mass Separator ISOLDE Facility: the Target Heater

    CERN Document Server

    Sánchez-Conejo, Jorge

    2003-01-01

    The purpose of the Heater Application is to heat and cool the target and line used on the On-Line Isotope Mass Separator ISOLDE facility up to a desired temperature selected by the user. The application has been developed in Java, making use of the Java Development Kit 1.4 and the PS Java environment.

  20. Development of the robot for pressurizer electric heater inspection and repairing

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Seung Ho; Kim, Seung Ho; Su, Yong Chil

    1999-01-01

    In this study a robot system has been developed for inspection and maintenance of the pressurizer and the rod heaters. The developed robot system consists of four parts: two links, a support frame, a movable gripper, and a controller box. The robot is attached on the support frame, which is attached at the man-way flange of the pressurizer such that the robot is positioned inside pressurizer. To access arbitrary heater, at first two links horizontally rotate, and then the gripper suspended by two steel wires moves up and down by turing wire drum because the rod heaters are located about 8 meters under the robot and are arranged in two circular rows. The robot must be designed under several constraints such as its weight and collision with pressurized wall or spray nozzle because the robot is positioned and moves inside the pressurizer. To verify that the designed robot is free from collision during installation procedure and it can access any desired rod heater, it is simulated by 3-dimensional graphic software (RobCAD). For evaluating stress of the support frame finite element analysis is performed by using the ANSYS code.

  1. 16 CFR Appendix D3 to Part 305 - Water Heaters-Oil

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Water Heaters-Oil D3 Appendix D3 to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULE CONCERNING... Part 305—Water Heaters—Oil Range Information CAPACITY FIRST HOUR RATING Range of Estimated...

  2. Tip-based chemical vapor deposition with a scanning nano-heater

    NARCIS (Netherlands)

    Gaitas, A.

    2013-01-01

    In this preliminary effort, a moving nano-heater directs a chemical vapor deposition reaction (nano-CVD) demonstrating a tip-based nanofabrication (TBN) method. Localized nano-CVD of copper (Cu) and copper oxide (CuO) on a silicon (Si) and silicon oxide (SiO2) substrate from gasses, namely sublimate

  3. Study of Exhaust Emissions Reduction of a Diesel Fuel Operated Heater During Transient Mode of Operation

    Directory of Open Access Journals (Sweden)

    Miklánek Ľubomír

    2014-10-01

    Full Text Available Diesel fuel operated heaters (FOHs are generally used as an independent heat source for any system in which a diesel fuel and battery power is available. Based on the fact that future engines will become even more efficient and thus less waste heat will be available to heat the passenger compartment, independent heat sources will be even more necessary.

  4. Development of Multi-Stage Steam Injector for Feedwater Heaters in Simplified Nuclear Power Plant

    Science.gov (United States)

    Narabayashi, Tadashi; Ohmori, Shuichi; Mori, Michitsugu; Asanuma, Yutaka; Iwaki, Chikako

    A steam injector (SI) is a simple, compact and passive pump and also acts as a high-performance direct-contact compact heater to heat up feedwater by using extracted steam from the turbine. To develop high performance compact feedwater heater, it is necessary to quantify the characteristics between physical properties of the flow field. Its performance depends on the phenomena of steam condensation onto the water jet surface and heat transfer in the water jet due to turbulence on to the phase-interface. The analysis was conducted by using CFD code embedded separate two-phase flow models that were confirmed by the experimental data. As the four-stage SI is compact heater, the system is expected to bring about great simplification and materials-saving effects, and high reliability of its operation. Therefore, it is confirmed that the simplification of the power plant by replacing all low-pressure feedwater heaters with the four-stage SI system, having steam extraction pressures equal to those for the existing ABWR system.

  5. 16 CFR Appendix J1 to Part 305 - Pool Heaters-Gas

    Science.gov (United States)

    2010-01-01

    ... Part 305—Pool Heaters—Gas Range Information Manufacturer's rated heating capacity Range of Thermal... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Pool Heaters-Gas J1 Appendix J1 to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULE...

  6. An efficient water flow control approach for water heaters in direct load control

    NARCIS (Netherlands)

    Belov, Alexander; Meratnia, Nirvana; Zwaag, van der Berend Jan; Havinga, Paul

    2014-01-01

    Tank water heaters (WHs) are present in a prevailing number of European households. Serving as energy buffers WHs have come under the spotlight of various direct load control (DLC) programs over the last few decades. Although DLC has proven to be an efficient measure towards daily peak demand shavin

  7. 16 CFR Appendix J2 to Part 305 - Pool Heaters-Oil

    Science.gov (United States)

    2010-01-01

    ... Part 305—Pool Heaters—Oil Range Information Manufacturer's rated heating capacities Range of Thermal... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Pool Heaters-Oil J2 Appendix J2 to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULE...

  8. Guidebook for the Development of a Nationally Appropriate Mitigation Action for Solar Water Heaters

    DEFF Research Database (Denmark)

    Haselip, James Arthur; Lütken, Søren E.; Sharma, Sudhir

    This guidebook provides an introduction to designing government-led interventions to scale up investment in solar water heater (SWH) markets, showing how these interventions can be packaged as Nationally Appropriate Mitigation Actions (NAMAS). Reflecting the changing balance in global greenhouse...

  9. Structural Benchmark Creep Testing for the Advanced Stirling Convertor Heater Head

    Science.gov (United States)

    Krause, David L.; Kalluri, Sreeramesh; Bowman, Randy R.; Shah, Ashwin R.

    2008-01-01

    The National Aeronautics and Space Administration (NASA) has identified the high efficiency Advanced Stirling Radioisotope Generator (ASRG) as a candidate power source for use on long duration Science missions such as lunar applications, Mars rovers, and deep space missions. For the inherent long life times required, a structurally significant design limit for the heater head component of the ASRG Advanced Stirling Convertor (ASC) is creep deformation induced at low stress levels and high temperatures. Demonstrating proof of adequate margins on creep deformation and rupture for the operating conditions and the MarM-247 material of construction is a challenge that the NASA Glenn Research Center is addressing. The combined analytical and experimental program ensures integrity and high reliability of the heater head for its 17-year design life. The life assessment approach starts with an extensive series of uniaxial creep tests on thin MarM-247 specimens that comprise the same chemistry, microstructure, and heat treatment processing as the heater head itself. This effort addresses a scarcity of openly available creep properties for the material as well as for the virtual absence of understanding of the effect on creep properties due to very thin walls, fine grains, low stress levels, and high-temperature fabrication steps. The approach continues with a considerable analytical effort, both deterministically to evaluate the median creep life using nonlinear finite element analysis, and probabilistically to calculate the heater head s reliability to a higher degree. Finally, the approach includes a substantial structural benchmark creep testing activity to calibrate and validate the analytical work. This last element provides high fidelity testing of prototypical heater head test articles; the testing includes the relevant material issues and the essential multiaxial stress state, and applies prototypical and accelerated temperature profiles for timely results in a

  10. Studying creation of bulk elementary excitation by heaters in superfluid helium-Ⅱ at low temperatures

    Institute of Scientific and Technical Information of China (English)

    ZAKHARENKO A.A.

    2007-01-01

    In this paper, the obtained experimental results concerning creation of bulk elementary excitations (BEEs) in isotopically pure liquid 4He at low temperatures ~60 mK are discussed. Positive rotons' (R+-rotons) creation by a pulsed heater was studied. Signals were recorded for the following quantum processes: quantum evaporation of 4He-atoms from the free liquid-helium surface by the BEEs of the liquid helium-Ⅱ, and BEEs reflection from the free surface back into the bulk liquid. Typical signals are shown, and ratios of signal amplitudes are evaluated. For long heater pulses from 5 to 10 μs, appearance of the second atomic cloud consisting of evaporated 4He-atoms was observed in addition to the first atomic cloud. It is thought that the first atomic cloud of the evaporated helium atoms consists of very fast 4He-atoms with energies ~35 K evaporated by positive rotons with the special energies ~17 K (~2ER~2×8.6 K with ER representing the roton minimum energy) corresponding to the third non-dispersive Zakharenko wave. The second cloud of slower 4He-atoms was created by surface elementary excitations (SEEs or ripplons) possessing the special energies ~7.15 K representing the binding energy. It was assumed that such SEEs can be created by phonons incoming to the liquid surface with special energies ~6.2 K corresponding to the first non-dispersive Zakharenko wave,which can interact at the liquid surface with the same phonons already reflected from the surface for long heater pulses. Also, some pulsed-heater characteristics were studied in order to better understand the features of such heaters in low temperature experiments.

  11. EFFECT OF DISCRETE HEATER AT THE VERTICAL WALL OF THE CAVITY OVER THE HEAT TRANSFER AND ENTROPY GENERATION USING LBM

    Directory of Open Access Journals (Sweden)

    Mousa Farhadi

    2011-01-01

    Full Text Available In this paper Lattice Boltzmann Method (LBM was employed for investigation the effect of the heater location on flow pattern, heat transfer and entropy generation in a cavity. A 2D thermal lattice Boltzmann model with 9 velocities, D2Q9, is used to solve the thermal flow problem. The simulations were performed for Rayleigh numbers from 103 to 106 at Pr = 0.71. The study was carried out for heater length of 0.4 side wall length which is located at the right side wall. Results are presented in the form of streamlines, temperature contours, Nusselt number and entropy generation curves. Results show that the location of heater has a great effect on the flow pattern and temperature fields in the enclosure and subsequently on entropy generation. The dimensionless entropy generation decreases at high Rayleigh number for all heater positions. The ratio of averaged Nusselt number and dimensionless entropy generation for heater located on vertical and horizontal walls was calculated. Results show that higher heat transfer was observed from the cold walls when the heater located on vertical wall. On the other hand, heat transfer increases from the heater surface when it located on the horizontal wall.

  12. Measures to Improve Fired Heater Thermal Efficiency During Design Stage for New Refinery%新建炼厂设计阶段提高加热炉热效率的措施

    Institute of Scientific and Technical Information of China (English)

    史方军; 赵志谦

    2011-01-01

    在炼油加工过程中,加热炉是能耗大户.对新建炼厂,在设计阶段提高加热炉热效率,对节能减排有重要意义.在设计过程中,采取燃料气脱硫等措施以降低排烟温度、降低空气过刹系数和漏风量等措施以降低过剩空气量、优化设计加热炉衬里以降低散热损失、优化余热回收系统方案和控制方案以提高烟气余热利用率和操作稳定性、利用装置废热预热助燃空气,可以有效提高加热炉的设计热效率.%During the oil refining process, the fired heater is the main energy - consuming equipment.Improving fired heater's thermal efficiency during the design stage has significant impact on energy conservation and emission reduction.In order to improve the thermal efficiency, the following measures can be adopted: reducing the temperature of the discharge flue gas by fuel gas desulphurization; reducing excess air ratio and air leakage; optimizing the design of fired heater lining to decrease the external heat loss;scheme optimization of flue exhaust - heat recovery system and control system in order to improve the exhaust - heat utilization ratio and operational stability; preheating combustion air with the unit waste heat.

  13. Indoor simulation and testing of photovoltaic thermal (PV/T) air collectors

    NARCIS (Netherlands)

    Solanki, S.C.; Dubey, Swapnil; Tiwari, Arvind

    2009-01-01

    An indoor standard test procedure has been developed for thermal and electrical testing of PV/T collectors connected in series. For this, a PV/T solar air heater has been designed, fabricated and its performance over different operating parameters were studied. Based on the energy balance equations,

  14. 76 FR 69927 - Approval of Air Quality Implementation Plans; California; South Coast; Attainment Plan for 1997...

    Science.gov (United States)

    2011-11-09

    ... never effectively plan for air quality improvement if they had to constantly revise their inventories as...-91-019, July 1991; ``Emission Projections,'' STAPPA/ALAPCO/EPA Emission Inventory Improvement Project... precursor emissions from industrial boilers and heaters, and that it should require replacement of old...

  15. 78 FR 53029 - Air Quality: Revision to Definition of Volatile Organic Compounds-Exclusion of trans

    Science.gov (United States)

    2013-08-28

    ... non-aerosol solvents and blowing agents for insulating foams; and manufacturers of refrigeration... heaters and as a refrigerant in commercial chillers and waste heat recovery (Rankin cycle) systems. A... precautions common to the refrigeration and air conditioning industry, the foam blowing industry and...

  16. Commercial Integrated Heat Pump with Thermal Storage --Demonstrate Greater than 50% Average Annual Energy Savings, Compared with Baseline Heat Pump and Water Heater (Go/No-Go) FY16 4th Quarter Milestone Report

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Bo [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Baxter, Van D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Rice, C. Keith [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Abu-Heiba, Ahmad [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-03-01

    For this study, we authored a new air source integrated heat pump (AS-IHP) model in EnergyPlus, and conducted building energy simulations to demonstrate greater than 50% average energy savings, in comparison to a baseline heat pump with electric water heater, over 10 US cities, based on the EnergyPlus quick-service restaurant template building. We also assessed water heating energy saving potentials using ASIHP versus gas heating, and pointed out climate zones where AS-IHPs are promising.

  17. Experimental investigation on thermoelectric air conditioner driven by solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Xu Lizhen; Li Yan; Qin Feng; Chen Changhe [Key Lab. for Thermal Science and Power Engineering, Ministry of Education of China, Dept. of Thermal Engineering, Tsinghua Univ., BJ (China)

    2008-07-01

    The thermoelectric devices can convert solar energy into a temperature difference to act as coolers or heater with the help of PV arrays, especially in the remote area without power network. The experiment device is composed of thermoelectric refrigeration modules, fan, air channel, cooling cabinet and temperature measurement system. The thermoelectric air conditioner (TEAC) system is tested with different working electric voltage of thermopile; its operational parameters are obtained for different operational conditions. The Coefficient of Performance (COP) is analyzed in experimental ways. The factors that affect the efficiency of TEAC are discussed on the basis of experimental investigation by air-cooled thermoelectric module and water-cooled thermoelectric module. (orig.)

  18. Modernization of the feedwater heaters control level of the Almaraz I Nuclear Power Plant by OVATION system; Modernizacion del control de nivel de los calentadores de agua de alimentacion de C.N. Almaraz I mediante el sistema OVATION

    Energy Technology Data Exchange (ETDEWEB)

    Madronal Rodriguez, E.; Cabrero Munoz, J. E.

    2010-07-01

    As a result of the process of technological renovation of the heaters system and the power increase project, Almaraz Nuclear Power Plant has made several design changes in the feedwater heaters system. Within these changes, the old heaters control loops are replaced because the new power will increase the heaters drainage caudal. This modernization is carried out using the OVATION control system.

  19. The Heat Exchanger Performance of Shell and Multi Tube Helical Coil as a Heater through the Utilization of a Diesel Machine’s Exhaust Gas

    Directory of Open Access Journals (Sweden)

    . Zainuddin

    2016-04-01

    Full Text Available A review on reutilization of heat waste from a diesel machine is absolutely important. This is because the exhaust gas potential of a Diesel machine keeps increasing and not much has been utilized by the industry. One of the techniques of reutilizing the heat waste in industry is by using a heat exchanger. The technique is also very useful for the environment because it can reduce air pollution caused by the exhaust gas of the diesel machine. The main purpose of the research is to find out the capability of shell and multi-tube helical coil HE as an air heater by utilizing the exhaust gas of the Diesel machine. The heat exchanger of shell and multi-tube helical coil  utilizes the exhaust thermal gas of the Diesel machine as the air heater already made. The apparatus has the following dimension: the shell length of 1.05 m, diameter 0.1524 m, tube length of 3.25 m with 20 coils, tube diameter of 0.011 m, coil diameter of 0.0508 m with 4 helical coils. The type of Diesel machine to use in the testing is 4FB1 Isuzu Diesel engine. The machine has the maximum machine power and rotation of 54 kW and 3,600 rpm. The performance testing of heat exchanger has been conducted in some variations of Diesel machine rotations of 1,500 rpm, 1,750 rpm, 2,000 rpm, 2,250 rpm and 2,500 rpm. The testing result shows a maximum effectiveness to happen at the machine rotation of 1,500 rpm. The maximum effectiveness to get is 67.8% and then it goes down drastically in accordance with the increase of air mass flow rate. The hot air temperature created is from 47.1°C to 52.3°C so that it can be used for the purpose of drying up the unhulled rice.

  20. 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.

  1. Performance and energy costs associated with scaling infrared heater arrays for warming field plots from 1 to 100 m

    Science.gov (United States)

    To study the likely effects of global warming on open-field vegetation, hexagonal arrays of infrared heaters are currently being used for low-stature (scales, herein we show that excellent uniformity of the warming can be achieved using...

  2. Influence of Superheated Steam Temperature Regulation Quality on Service Life of Boiler Steam Super-Heater Metal

    Directory of Open Access Journals (Sweden)

    G. T. Kulakov

    2009-01-01

    Full Text Available The paper investigates influence of change in quality of superheated steam temperature regulations on service life of super-heater metal. А dependence between metal service life and dispersion value for different steel grades has been determined in the paper. Numerical values pertaining to increase of super-heater metal service life in case of transferring from manual regulation to standard system of automatic regulation (SAR have been determined and in case of transferring from standard SAR to improved SAR. The analysis of tabular data and plotted dependencies makes it possible to conclude that any change in conditions of convection super-heater metal work due to better quality of the regulation leads to essential increase of time period which is left till the completion of the service life of a super-heater heating surface.

  3. Indoor simulation and testing of photovoltaic thermal (PV/T) air collectors

    Energy Technology Data Exchange (ETDEWEB)

    Solanki, S.C.; Dubey, Swapnil [Centre for Energy Studies, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016 (India); Tiwari, Arvind [Department of Design, Production and Management, University of Twente, Enschede (Netherlands)

    2009-11-15

    An indoor standard test procedure has been developed for thermal and electrical testing of PV/T collectors connected in series. For this, a PV/T solar air heater has been designed, fabricated and its performance over different operating parameters were studied. Based on the energy balance equations, in a steady state condition, a thermal model has been developed. Comparison between experimental and theoretical results were also been carried out. The thermal and electrical efficiency of the solar heater is 42% and 8.4%, respectively. This test procedure can be used by manufacturers for testing of different types of PV modules in order to optimize its products. (author)

  4. Electric tubing heater improves well production in CO[sub 2] flood

    Energy Technology Data Exchange (ETDEWEB)

    Baud, W. (Shell Western E and P, Houston, TX (United States)); Eastlund, B. (Production Technologies International Inc., Houston, TX (United States))

    1994-04-18

    Installation of a downhole heater in a well eliminated production interruption caused by downhole paraffin and hydrate buildup, exacerbated by cooling effects of CO[sub 2]. The well is one of 20 operated by Shell Western E and P Inc. in the CO[sub 2]-flooded portion of the South Crossett Devonian Unit (SCDU) in the Permian basin of West Texas. Prior to heater installation, the well's production routinely choked off in 2 days unless the downhole impairment was mechanically removed. Mechanical cutting established that the paraffin and hydrate buildup was in the upper 2,000 ft of the 5,300-ft well. The fluid exit temperature, depending on the choke setting, fluctuated between 14 and 30 F. The paper describes the unsuccessful results from conventional treatments, and the new method.

  5. Experimental Investigation of a Natural Circulation Solar Domestic Water Heater Performance under Standard Consumption Rate

    DEFF Research Database (Denmark)

    Kolaei, Alireza Rezania; Taherian, H.; Ganji, D. D.

    2012-01-01

    consumption influence on the solar water heater efficiency, and on the input temperature of the collector are studied and the delivered daily useful energy has been obtained. The results show that by withdrawing from storage tank, the system as well as its collector efficiency will increase. Considering......This paper reports experimental studies on the performance of a natural circulation solar water heater considering the weather condition of a city in north of Iran. The tests are done on clear and partly cloudy days. The variations of storage tank temperature due to consumption from the tank, daily...... the value of the coefficient FRUL and τα, which are obtained experimentally as 6.03 and 0.83 respectively, average. monthly total load that is covered by this solar water heating system is estimated....

  6. Characterization of large cadmium zinc telluride crystals grown by traveling heater method

    DEFF Research Database (Denmark)

    Chen, H.; Awadalla, S.A.; Iniewski, K.

    2008-01-01

    The focus of this paper is to evaluate thick, 20 X 20 X 10 and 10 X 10 X 10 mm(3), cadmium zinc telluride (CZT), Cd0.9Zn0.1Te, crystals grown using the traveling heater method (THIM). The phenomenal spectral performance and small size and low concentration of Te inclusions/precipitates of these c......The focus of this paper is to evaluate thick, 20 X 20 X 10 and 10 X 10 X 10 mm(3), cadmium zinc telluride (CZT), Cd0.9Zn0.1Te, crystals grown using the traveling heater method (THIM). The phenomenal spectral performance and small size and low concentration of Te inclusions...

  7. A highly crystalline single Au wire network as a high temperature transparent heater.

    Science.gov (United States)

    Rao, K D M; Kulkarni, Giridhar U

    2014-06-07

    A transparent conductor which can generate high temperatures finds important applications in optoelectronics. In this article, a wire network made of Au on quartz is shown to serve as an effective high temperature transparent heater. The heater has been fabricated by depositing Au onto a cracked sacrificial template. The highly interconnected Au wire network thus formed exhibited a transmittance of ∼87% in a wide spectral range with a sheet resistance of 5.4 Ω □(-1). By passing current through the network, it could be joule heated to ∼600 °C within a few seconds. The extraordinary thermal performance and stability owe much to the seamless junctions present in the wire network. Furthermore, the wire network gets self-annealed through joule heating as seen from its increased crystallinity. Interestingly, both transmittance and sheet resistance improved following annealing to 92% and 3.2 Ω □(-1), respectively.

  8. Benchmark Calibration Tests Completed for Stirling Convertor Heater Head Life Assessment

    Science.gov (United States)

    Krause, David L.; Halford, Gary R.; Bowman, Randy R.

    2005-01-01

    A major phase of benchmark testing has been completed at the NASA Glenn Research Center (http://www.nasa.gov/glenn/), where a critical component of the Stirling Radioisotope Generator (SRG) is undergoing extensive experimentation to aid the development of an analytical life-prediction methodology. Two special-purpose test rigs subjected SRG heater-head pressure-vessel test articles to accelerated creep conditions, using the standard design temperatures to stay within the wall material s operating creep-response regime, but increasing wall stresses up to 7 times over the design point. This resulted in well-controlled "ballooning" of the heater-head hot end. The test plan was developed to provide critical input to analytical parameters in a reasonable period of time.

  9. Application of a Linear Input/Output Model to Tankless Water Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Butcher T.; Schoenbauer, B.

    2011-12-31

    In this study, the applicability of a linear input/output model to gas-fired, tankless water heaters has been evaluated. This simple model assumes that the relationship between input and output, averaged over both active draw and idle periods, is linear. This approach is being applied to boilers in other studies and offers the potential to make a small number of simple measurements to obtain the model parameters. These parameters can then be used to predict performance under complex load patterns. Both condensing and non-condensing water heaters have been tested under a very wide range of load conditions. It is shown that this approach can be used to reproduce performance metrics, such as the energy factor, and can be used to evaluate the impacts of alternative draw patterns and conditions.

  10. Perancangan Sistem Pemantauan Pengendali Suhu pada Stirred Tank Heater menggunakan Supervisory Control and Data Acquisition (SCADA

    Directory of Open Access Journals (Sweden)

    Ike Bayusari

    2013-04-01

    Full Text Available This paper discusses design of a suhue control monitoring system in stirred tank heater system that has an important function in industrial processes. Monitoring of suhue control system in stirred tank heater is designed using Supervisory Control and Data Acquisition (SCADA that control function of industrial processes. While the actuator to be controlled is the position of burner openings, so that the heat can be adjusted to meet a predetermined set-point. The suhue controller that is also used as a Remote Terminal Unit (RTU is Programmable Logic Controller (PLC. The testing result showed on SCADA system was quite good, where the average percentage of deviation for testing of set-point data was 0.76687%, and the percentage of deviation for testing of suhue data was 0.082%.

  11. Heat Pump Water Heater Technology Assessment Based on Laboratory Research and Energy Simulation Models: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Hudon, K.; Sparn, B.; Christensen, D.; Maguire, J.

    2012-02-01

    This paper explores the laboratory performance of five integrated Heat Pump Water Heaters (HPWHs) across a wide range of operating conditions representative of US climate regions. Laboratory results demonstrate the efficiency of this technology under most of the conditions tested and show that differences in control schemes and design features impact the performance of the individual units. These results were used to understand current model limitations, and then to bracket the energy savings potential for HPWH technology in various US climate regions. Simulation results show that HPWHs are expected to provide significant energy savings in many climate zones when compared to other types of water heaters (up to 64%, including impact on HVAC systems).

  12. Solar Probe Plus MAG Sensor Thermal Design for Low Heater Power and Extreme Thermal Environment

    Science.gov (United States)

    Choi, Michael K.

    2015-01-01

    The heater power available for the Solar Probe Plus FIELDS MAG sensor is less than half of the heritage value for other missions. Nominally the MAG sensors are in the spacecraft's umbra. In the worst hot case, approximately 200 spacecraft communication downlinks, up to 10 hours each, are required at 0.7 AU. These downlinks require the spacecraft to slew 45 deg. about the Y-axis, exposing the MAG sensors and boom to sunlight. This paper presents the thermal design to meet the MAG sensor thermal requirements in the extreme thermal environment and with low heater power. A thermal balance test on the MAG sensor engineering model has verified the thermal design and correlated the thermal model for flight temperature predictions.

  13. An in-situ heater for the XAS beamline (12-ID) in Australia

    Science.gov (United States)

    Johannessen, B.; Hussain, Z. S.; East, D. R.; Gibson, M. A.

    2013-04-01

    To accommodate for a growing number of requests by our user community an in-situ heater has been commissioned for the X-ray absorption spectroscopy (XAS) beamline 12-ID at the Australian Synchrotron. Here, we present an in-situ method for calibrating the temperature of the heating stage based on an anharmonic, correlated Einstein model. Specifically, we show that a temperature-dependant study of a bulk metallic foil (7.5 μm Cu) can be used to accurately calibrate the temperature of the heater. We also present the temperature-dependant coordination number, bond length, Debye-Waller factor, and third order cumulant to the bond length distribution function of the material from 18K to 1074K. At the higher temperatures we find that the atomic structure is comparable to that of an amorphous or liquid material indicating a gradual transition from crystalline to disordered atomic structure.

  14. Skin-effect down hole electric heater for heavy oil and high wax content oil applications

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Chenglin; Wang, Hui; Liu, Yanhua [Liaoning Huafu Petroleum High-Tech Co., Ltd. (China); Xiao, Jon H; Klotz, Eric [ANDMIR Environmental Group Canada Inc. (Canada)

    2011-07-01

    With the increased production of oil and the depletion of conventional reserves, operators have started to exploit heavy oil and high wax content oil. Adequate production of such oils is difficult to achieve due to viscosity increase and mobility decrease during lifting as a result of heat loss. The down-hole electric heater has been developed to resolve these issues with the application of skin-effect electric heating technology. The aim of this paper is to present how this technology improves the production of heavy oil and waxy oil. Applications of the technology to wells in Chinese oilfields are studied. Results proved the technology to be efficient while being based on a simple process and operating in an easy and safe manner. This paper showed that the down-hole electric heater is a breakthrough technology, resolving the issues encountered in the heavy oil and waxy oil exploitation field, with broad application prospects.

  15. Analysis of a Permanent Magnet Eddy Current Heater Driven by a Wind Turbine

    OpenAIRE

    TUDORACHE, T.; MELCESCU, L.; Predescu, M.

    2015-01-01

    This paper deals with the numerical analysis and optimal design of a Permanent Magnet Eddy Current Heater (PMECH) driven by a wind turbine. This study includes a preliminary sizing of the wind turbine, an optimal design of the PMECH from cost reduction point of view, a heat transfer analysis of the device and a study of the dynamic response of the wind system. The electromagnetic and heat transfer analysis is based on Finite Element Method (FEM) implemented in the Flux sof...

  16. Expert Meeting Report: Recommendations for Applying Water Heaters in Combination Space and Domestic Water Heating Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rudd, A.; Ueno, K.; Bergey, D.; Osser, R.

    2012-07-01

    The topic of this meeting was 'Recommendations For Applying Water Heaters In Combination Space And Domestic Water Heating Systems.' Presentations and discussions centered on the design, performance, and maintenance of these combination systems, with the goal of developing foundational information toward the development of a Building America Measure Guideline on this topic. The meeting was held at the Westford Regency Hotel, in Westford, Massachusetts on 7/31/2011.

  17. Thermodynamic Analysis of a Steam Power Plant with Double Reheat and Feed Water Heaters

    OpenAIRE

    2014-01-01

    A steam cycle with double reheat and turbine extraction is presented. Six heaters are used, three of them at high pressure and the other three at low pressure with deaerator. The first and second law analysis for the cycle and optimization of the thermal and exergy efficiencies are investigated. An exergy analysis is performed to guide the thermodynamic improvement for this cycle. The exergy and irreversibility analyses of each component of the cycle are determined. Effects of turbine inlet p...

  18. Water solar distiller productivity enhancement using concentrating solar water heater and phase change material (PCM)

    OpenAIRE

    Miqdam T. Chaichan; Hussein A. Kazem

    2015-01-01

    This paper investigates usage of thermal energy storage extracted from concentrating solar heater for water distillation. Paraffin wax selected as a suitable phase change material, and it was used for storing thermal energy in two different insulated treasurers. The paraffin wax is receiving hot water from concentrating solar dish. This solar energy stored in PCM as latent heat energy. Solar energy stored in a day time with a large quantity, and some heat retrieved for later use. Water’s temp...

  19. Programmable Thermostats for MPLM Shell Heater Control ULF1. 1; Thermal Performances

    Science.gov (United States)

    Glasgow, Shaun; Clark, Dallas; Trichilo, Michele; Trichilo, Michele

    2007-01-01

    The Multi-Purpose Logistics Module (MPLM) is the primary carrier for "pressurized" logistics to and from the International Space Station (ISS). The MPLM is transported in the payload bay of the Space Shuttle and is docked to the ISS for unloading, and reloading, of contents within the ISS shirt sleeve environment. Foil heaters, controlled originally with bi-metallic thermostats, are distributed across the outside of the MPLM structure and are utilized to provide energy to the structure to avoid exposure to cold temperatures and prevent condensation. The existing bi-metallic, fixed temperature set point thermostats have been replaced with Programmable Thermostats Modules (PTMs) in the Passive Thermal Control Subsystem (PTCS) 28Vdc shell heater circuits. The goal of using the PTM thermostat is to improve operational efficiency of the MPLM on-orbit shell heaters by providing better shell temperature control via feedback control capability. Each heater circuit contains a programmable thermostat connected to an external temperature sensor, a Resistive Temperature Device (RTD), which is used to provide continuous temperature monitoring capability. Each thermostat has programmable temperature set points and control spans. The data acquisition system uses a standard RS-485 serial interface communications cable to provide digital control capability. The PTM system was designed by MSFC, relying upon ALTEC support for their integration within the MPLM system design, while KSC performed the installation and ground checkout testing of the thermostat and RS-485 communication cable on the MPLM FM1 flight module. The PTMs were used for the first time during the STS-121/ULF1.1 mission. This paper will describe the design, development and verification of the PTM system, as well as the PTM flight performance and comparisons with SINDA thermal model predictions.

  20. Effect of Installation of Solar Collector on Performance of Balcony Split Type Solar Water Heaters

    OpenAIRE

    Xu Ji; Ming Li; Weidong Lin; Tufeng Zheng; Yunfeng Wang

    2015-01-01

    The influences of surface orientation and slope of solar collectors on solar radiation collection of balcony split type solar water heaters for six cities in China were analyzed by employing software TRNSYS. The surface azimuth had greater effect on solar radiation collection in high latitude regions. For deviation of the surface slope angle within ±20° around the optimized angle, the variation of the total annual collecting solar radiation was less than 5%. However, with deviation of 70° to ...

  1. Heat transfer and energy analysis of a solar air collector with smooth plate

    Science.gov (United States)

    Chabane, Foued; Moummi, Noureddine

    2014-04-01

    The heat transfer and thermal performance of a single pass solar air heater a smooth plate was investigated experimentally. In the present paper, energy and heat transfer analysis of a solar air collector with smooth plate, this technique is used to determine the optimal thermal performance of flat plate solar air heater by considering the different system and operating parameters to obtain maximum thermal performance. Thermal performance is obtained for different mass flow rate varying in the array 0.0108-0.0202 kg/s with five values, solar intensity; tilt angle and ambient temperature. We discuss the thermal behavior of this type of collector with new design and with my proper construction. An experimental study was carried out on a prototype installed on the experimental tests platform within the University of Biskra in the Algeria. The effects of air mass flow rate, emissivity of channel plates and wind heat transfer coefficient on the accuracy of the criterion are also investigated.

  2. Stability Analysis of Absorption Chiller-Heaters by Applying Transfer Function

    Science.gov (United States)

    Fujii, Tatsuo; Miyake, Satoshi; Oka, Masahiro; Mori, Kiyoyuki

    A transfer function approach is found to be a practical method for ensuring stable operation of absorption chiller-heaters. The transfer function model is based on a solution-circuit of the machine, which dominates the stability of the operation. This model includes a solution pump, a generator with an overflow weir, and a float valve. We found that the solution-circuit system is designed with the cascade control, which makes the system stable. In this construction, the float valve actuates a primary control loop, and the overflow weir actuates a secondary loop. The effects of the characteristic of the solution pump and the overflow weir are estimated by the degree of the stabilities, which are the gain margin and the phase margin. We found that the characteristic of the solution pump strongly effects the stability by enhancing the effect of the cascade control and improving the stability. So it is essential for a better stability analysis model. According to these results, the established model is useful for quantitatively predicting the stabilities of a chiller-heater in operation, and simultaneously reducing its size and improving the stability of operation. We conclude that the methodology based on transfer function can provide compact and reliable absorption chiller-heaters.

  3. Experimental Study of Thermoelectric Heat Pump Water Heater with Exhaust Heat Recovery from Kitchens

    Institute of Scientific and Technical Information of China (English)

    LIU Zhong-bing; ZHANG Ling; YANG Zhang; XU Ming; HAN Tian-he

    2009-01-01

    A new kind of thermoelectric heat pump water heater for kitchens exhaust heat recovery was pre-sented,and its performances were investigated under different operating voltages.The experiment results show that the coefficient of performance decreases and the temperature difference between the hot and cold sides be-comes larger with the increase of the operating voltage,but the heating time becomes short.The higher the temperature of water,the greater the temperature difference between the hot and cold sides,leading to a smaller eoeffieient of performance.Under an exhaust temperature of 36℃,the coefficient of performance decreases from 1.66 tO 1.22 when the temperature of water increases from 28℃to 46℃with operating voltage 16 V.Performance tests illustrate that,compared with the conventional electrical water heaters,the new kind of ther-moelectric heat pump water heater is more coefficient.

  4. Impact on Water Heater Performance of Heating Methods that Promote Tank Temperature Stratification

    Energy Technology Data Exchange (ETDEWEB)

    Gluesenkamp, Kyle R [ORNL; BushPE, John D [Electric Power Research Institute (EPRI)

    2016-01-01

    During heating of a water heater tank, the vertical temperature stratification of the water can be increased or decreased, depending on the method of heating. Methods that increase stratification during heating include (1) removing cold water from the tank bottom, heating it, and re-introducing it to the tank top at relatively low flow rate, (2) using a heat exchanger wrapped around the tank, through which heating fluid (with finite specific heat) flows from top to bottom, and (3) using an immersed heat element that is relatively high in the tank. Using such methods allows for improved heat pump water heater (HPWH) cycle efficiencies when the heat pump can take advantage of the lower temperatures that exist lower in the tank, and accommodate the resulting glide. Transcritical cycles are especially well-suited to capitalize on this opportunity, and other HPWH configurations (that have been proposed elsewhere) may benefit as well. This work provides several stratification categories of heat pump water heater tank configurations relevant to their stratification potential. To illustrate key differences among categories, it also compiles available experimental data for (a) single pass pumped flow, (b) multi-pass pumped flow, and (c) top-down wrapped tank with transcritical refrigerant.

  5. Screen-Printed Fabrication of PEDOT:PSS/Silver Nanowire Composite Films for Transparent Heaters

    Directory of Open Access Journals (Sweden)

    Xin He

    2017-02-01

    Full Text Available A transparent and flexible film heater was fabricated; based on a hybrid structure of poly(3,4-ethylenedioxythiophene poly(styrenesulfonate (PEDOT:PSS and silver nanowires (Ag NWs using a screen printing; which is a scalable production technology. The resulting film integrates the advantages of the two conductive materials; easy film-forming and strong adhesion to the substrate of the polymer PEDOT:PSS; and high conductivity of the Ag NWs. The fabricated composite films with different NW densities exhibited the transmittance within the range from 82.3% to 74.1% at 550 nm. By applying 40 V potential on the films; a stable temperature from 49 °C to 99 °C was generated within 30 s to 50 s. However; the surface temperature of the pristine PEDOT:PSS film did not increase compared to the room temperature. The composite film with the transmittance of 74.1% could be heated to the temperatures from 41 °C to 99 °C at the driven voltages from 15 V to 40 V; indicating that the film heater exhibited uniform heating and rapid thermal response. Therefore; the PEDOT:PSS/Ag NW composite film is a promising candidate for the application of the transparent and large-scale film heaters.

  6. Rapid thermal lysis of cells using silicon-diamond microcantilever heaters.

    Science.gov (United States)

    Privorotskaya, Natalya; Liu, Yi-Shao; Lee, Jungchul; Zeng, Hongjun; Carlisle, John A; Radadia, Adarsh; Millet, Larry; Bashir, Rashid; King, William P

    2010-05-07

    This paper presents the design and application of microcantilever heaters for biochemical applications. Thermal lysis of biological cells was demonstrated as a specific example. The microcantilever heaters, fabricated from selectively doped single crystal silicon, provide local resistive heating with highly uniform temperature distribution across the cantilevers. Very importantly, the microcantilever heaters were coated with a layer of 100 nm thick electrically insulating ultrananocrystalline diamond (UNCD) layer used for cell immobilization on the cantilever surface. Fibroblast cells or bacterial cells were immobilized on the UNCD/cantilever surfaces and thermal lysis was demonstrated via optical fluorescence microscopy. Upon electrical heating of the cantilever structures to 93 degrees C for 30 seconds, fibroblast cell and nuclear membrane were compromised and the cells were lysed. Over 90% of viable bacteria were also lysed after 15 seconds of heating at 93 degrees C. This work demonstrates the utility of silicon-UNCD heated microcantilevers for rapid cell lysis and forms the basis for other rapid and localized temperature-regulated microbiological experiments in cantilever-based lab on chip applications.

  7. Effect of Installation of Solar Collector on Performance of Balcony Split Type Solar Water Heaters

    Directory of Open Access Journals (Sweden)

    Xu Ji

    2015-01-01

    Full Text Available The influences of surface orientation and slope of solar collectors on solar radiation collection of balcony split type solar water heaters for six cities in China were analyzed by employing software TRNSYS. The surface azimuth had greater effect on solar radiation collection in high latitude regions. For deviation of the surface slope angle within ±20° around the optimized angle, the variation of the total annual collecting solar radiation was less than 5%. However, with deviation of 70° to 90°, the variation was up to 20%. The effects of water cycle mode, reverse slope placement of solar collector, and water tank installation height on system efficiency were experimentally studied. The thermal efficiencies of solar water heater with single row horizontal arrangement all-glass evacuated tubular collector were higher than those with vertical arrangement at the fixed surface slope angle of 90°. Compared with solar water heaters with flat-plate collector under natural circulation, the system thermal efficiency was raised up to 63% under forced circulation. For collector at reverse slope placement, the temperature-based water stratification in water tank deteriorated, and thus the thermal efficiency became low. For improving the system efficiency, an appropriate installation height of the water tank was suggested.

  8. Effect of Random Thermal Spikes on Stirling Convertor Heater Head Reliability

    Science.gov (United States)

    Shah, Ashwin R.; Korovaichuk, Igor; Halford, Gary R.

    2004-01-01

    Onboard radioisotope power systems being developed to support future NASA exploration missions require reliable design lifetimes of up to 14 yr and beyond. The structurally critical heater head of the high-efficiency developmental Stirling power convertor has undergone extensive computational analysis of operating temperatures (up to 650 C), stresses, and creep resistance of the thin-walled Inconel 718 bill of material. Additionally, assessment of the effect of uncertainties in the creep behavior of the thin-walled heater head, the variation in the manufactured thickness, variation in control temperature, and variation in pressure on the durability and reliability were performed. However, it is possible for the heater head to experience rare incidences of random temperature spikes (excursions) of short duration. These incidences could occur randomly with random magnitude and duration during the desired mission life. These rare incidences could affect the creep strain rate and therefore the life. The paper accounts for these uncertainties and includes the effect of such rare incidences, random in nature, on the reliability. The sensitivities of variables affecting the reliability are quantified and guidelines developed to improve the reliability are outlined. Furthermore, the quantified reliability is being verified with test data from the accelerated benchmark tests being conducted at the NASA Glenn Research Center.

  9. Full thermoelectric characterization of InAs nanowires using MEMS heater/sensors.

    Science.gov (United States)

    Karg, S F; Troncale, V; Drechsler, U; Mensch, P; Das Kanungo, P; Schmid, H; Schmidt, V; Gignac, L; Riel, H; Gotsmann, B

    2014-08-01

    Precise measurements of a complete set of thermoelectric parameters on a single indium-arsenide nanowire (NW) have been performed using highly sensitive, micro-fabricated sensing devices based on the heater/sensor principle. The devices were fabricated as micro electro-mechanical systems consisting of silicon nitride membranes structured with resistive gold heaters/sensors. Preparation, operation and characterization of the devices are described in detail. Thermal decoupling of the heater/sensor platforms has been optimized reaching thermal conductances as low as 20 nW K(-1) with a measurements sensitivity below 20 nW K(-1). The InAs NWs were characterized in terms of thermal conductance, four-probe electrical conductance and thermopower (Seebeck coefficient), all measured on a single NW. The temperature dependence of the parameters determining the thermoelectric figure-of-merit of an InAs NW was acquired in the range 200-350 K featuring a minor decrease of the thermal conductivity from 2.7 W (m K)(-1) to 2.3 W (m K)(-1).

  10. Temperature-controlled transparent-film heater based on silver nanowire-PMMA composite film.

    Science.gov (United States)

    He, Xin; Liu, A'lei; Hu, Xuyang; Song, Mingxia; Duan, Feng; Lan, Qiuming; Xiao, Jundong; Liu, Junyan; Zhang, Mei; Chen, Yeqing; Zeng, Qingguang

    2016-11-25

    We fabricated a high-performance film heater based on a silver nanowire and polymethyl methacrylate (Ag NW-PMMA) composite film, which was synthesized with the assistance of mechanical lamination and an in situ transfer method. The films exhibit excellent conductivity, high figure of merit, and strong adhesion of percolation network to substrate. By controlling NW density, we prepared the films with a transmittance of 44.9-85.0% at 550 nm and a sheet resistance of 0.13-1.40 Ω sq(-1). A stable temperature ranging from 130 °C-40 °C was generated at 3.0 V within 10-30 s, indicating that the resulting film heaters show a rapid thermal response, low driving voltage and stable temperature recoverability. Furthermore, we demonstrated the applications of the film heater in defrosting and a physical therapeutic instrument. A fast defrosting on the composite film with a transmittance of 88% was observed by applying a 9 V driving voltage for 20 s. Meanwhile, we developed a physical therapeutic instrument with two modes of thermotherapy and electronic-pulse massage by using the composite films as two electrodes, greatly decreasing the weight and power consumption compared to a traditional instrument. Therefore, Ag NW-PMMA film can be a promising candidate for diversified heating applications.

  11. Wavelength tuning and stabilization of microring-based filters using silicon in-resonator photoconductive heaters

    CERN Document Server

    Jayatilleka, Hasitha; Guillen-Torres, Miguel Angel; Caverley, Michael; Hu, Ricky; Jaeger, Nicolas A F; Chrostowski, Lukas; Shekhar, Sudip

    2015-01-01

    We demonstrate that n-doped resistive heaters in silicon waveguides show photoconductive effects having responsivities as high as 271 mA/W. These photoconductive heaters, integrated into microring resonator (MRR)-based filters, were used to automatically tune and stabilize the filter's resonance wavelength to the input laser's wavelength. This is achieved without requiring dedicated defect implantations, additional material depositions, dedicated photodetectors, or optical power tap-outs. Automatic wavelength stabilization of first-order MRR and second-order series-coupled MRR filters is experimentally demonstrated. Open eye diagrams were obtained for data transmission at 12.5 Gb/s while the temperature was varied by 5 C at a rate of 0.28 C/s. We theoretically show that series-coupled MRR-based filters of any order can be automatically tuned by using photoconductive heaters to monitor the light intensity in each MRR, and sequentially aligning the resonance of each MRR to the laser's wavelength.

  12. Temperature-controlled transparent-film heater based on silver nanowire-PMMA composite film

    Science.gov (United States)

    He, Xin; Liu, A.'lei; Hu, Xuyang; Song, Mingxia; Duan, Feng; Lan, Qiuming; Xiao, Jundong; Liu, Junyan; Zhang, Mei; Chen, Yeqing; Zeng, Qingguang

    2016-11-01

    We fabricated a high-performance film heater based on a silver nanowire and polymethyl methacrylate (Ag NW-PMMA) composite film, which was synthesized with the assistance of mechanical lamination and an in situ transfer method. The films exhibit excellent conductivity, high figure of merit, and strong adhesion of percolation network to substrate. By controlling NW density, we prepared the films with a transmittance of 44.9-85.0% at 550 nm and a sheet resistance of 0.13-1.40 Ω sq-1. A stable temperature ranging from 130 °C-40 °C was generated at 3.0 V within 10-30 s, indicating that the resulting film heaters show a rapid thermal response, low driving voltage and stable temperature recoverability. Furthermore, we demonstrated the applications of the film heater in defrosting and a physical therapeutic instrument. A fast defrosting on the composite film with a transmittance of 88% was observed by applying a 9 V driving voltage for 20 s. Meanwhile, we developed a physical therapeutic instrument with two modes of thermotherapy and electronic-pulse massage by using the composite films as two electrodes, greatly decreasing the weight and power consumption compared to a traditional instrument. Therefore, Ag NW-PMMA film can be a promising candidate for diversified heating applications.

  13. Experimental and Numerical Analysis of Air Flow, Heat Transfer and Thermal Comfort in Buildings with Different Heating Systems

    Science.gov (United States)

    Sabanskis, A.; Virbulis, J.

    2016-04-01

    Monitoring of temperature, humidity and air flow velocity is performed in 5 experimental buildings with the inner size of 3×3×3 m3 located in Riga, Latvia. The buildings are equipped with different heating systems, such as an air-air heat pump, air-water heat pump, capillary heating mat on the ceiling and electric heater. Numerical simulation of air flow and heat transfer by convection, conduction and radiation is carried out using OpenFOAM software and compared with experimental data. Results are analysed regarding the temperature and air flow distribution as well as thermal comfort.

  14. Comparative Research on Air Conditioner with Gas-injected Rotary Compressor through Injection Port on Blade

    OpenAIRE

    Xingru, Liu; Baolong, Wang; Wenxing, Shi

    2016-01-01

    Rotary compressors are widely utilized in air conditionders and heat pumps. However, when rotary compressors were applied in room air conditioners, VRFs and domestic water heaters, the systems will experience heavily degradation of the heating capacity and COP as the ambient temperature goes low. Aimed at these problems, considerable research has been carried out to raise a series of solutions, such as economizer technology, cascade-type vapor compression heat pump system and two stage coupli...

  15. Temperature distributions in trapezoidal built in storage solar water heaters with/without phase change materials

    Energy Technology Data Exchange (ETDEWEB)

    Tarhan, Sefa; Yardim, M. Hakan [Department of Farm Machinery, Faculty of Agriculture, Gaziosmanpasa University, Tasliciftlik Yerleskesi, 60240 Tokat (Turkey); Sari, Ahmet [Department of Chemistry, Faculty of Arts and Sciences, Gaziosmanpasa University, Tasliciftlik Yerleskesi, 60240 Tokat (Turkey)

    2006-09-15

    Built in storage solar water heaters (BSSWHs) have been recognized for their more compact constructions and faster solar gain than conventional solar water heaters, however, their water temperatures quickly go down during the cooling period. A trapezoidal BSSWH without PCM storage unit was used as the control heater (reference) to investigate the effect of two differently configured PCM storage units on the temperature distributions in water tanks. In the first design, myristic acid was filled into the PCM storage tank, which also served as an absorbing plate. In the second design, lauric acid was filled into the PCM storage tank, which also served as a baffle plate. The water temperature changes were followed by five thermocouples placed evenly and longitudinally into each of the three BSSWHs. The effects of the PCMs on the water temperature distributions depended on the configuration of the PCM storage unit and the longitudinal position in the water tanks. The use of lauric acid lowered the values of the peak temperatures by 15% compared to the control heater at the upper portion of the water tanks because of the low melting temperature of lauric acid, but it did not have any consistent effect on the retention of the water temperatures during the cooling period. The ability of the myristic acid storage unit to retain the water temperatures got more remarkable, especially at the middle portion of the water tank. The myristic acid storage increased the dip temperatures by approximately 8.8% compared to the control heater. In conclusion, lauric acid storage can be used to stabilize the water temperature during the day time, while the myristic acid storage unit can be used as a thermal barrier against heat loss during the night time because of its relatively high melting temperature and low heat conduction coefficient in its solid phase. The experimental results have also indicated that the thermal characteristics of the PCM and the configuration of the PCM storage

  16. Oxidation-resistant hybrid metal oxides/metal nanodots/silver nanowires for high performance flexible transparent heaters

    Science.gov (United States)

    Kim, A.-Young; Kim, Min Kyu; Hudaya, Chairul; Park, Ji Hun; Byun, Dongjin; Lim, Jong Choo; Lee, Joong Kee

    2016-02-01

    Despite its excellent optical, electrical, mechanical, and thermal performances, a silver nanowire (AgNW)-based transparent conducting heater (TCH) still demonstrates several drawbacks such as facile nanowire breakdown on application of a high DC voltage, easy oxidation when exposed to harsh environments, leading to increased surface resistivity, and high resistance among wire junctions causing nonhomogeneous temperature profiles. To overcome these issues, the AgNW was hybridized with other transparent heating materials made of fluorine-doped tin oxide (FTO) thin films and NiCr nanodots (FTO/NiCr/AgNW). The dispersed NiCr nanodots (~50 nm) and FTO thin films (~20 nm) electrically bridge the nanowire junctions leading to a decreased sheet resistance and uniform temperature profiles. The hybrid transparent heater shows excellent optical transmittance (>90%) and high saturation temperature (162 °C) at low applied DC voltage (6 V). Moreover, the FTO/NiCr/AgNW heater exhibits a stable sheet resistance in a hostile environment, hence highlighting the excellent oxidation-resistance of the heating materials. These results indicate that the proposed hybrid transparent heaters could be a promising approach to combat the inherent problems associated with AgNW-based transparent heaters for various functional applications.Despite its excellent optical, electrical, mechanical, and thermal performances, a silver nanowire (AgNW)-based transparent conducting heater (TCH) still demonstrates several drawbacks such as facile nanowire breakdown on application of a high DC voltage, easy oxidation when exposed to harsh environments, leading to increased surface resistivity, and high resistance among wire junctions causing nonhomogeneous temperature profiles. To overcome these issues, the AgNW was hybridized with other transparent heating materials made of fluorine-doped tin oxide (FTO) thin films and NiCr nanodots (FTO/NiCr/AgNW). The dispersed NiCr nanodots (~50 nm) and FTO thin films

  17. Air Pollution

    Science.gov (United States)

    Air pollution is a mixture of solid particles and gases in the air. Car emissions, chemicals from factories, dust, ... a gas, is a major part of air pollution in cities. When ozone forms air pollution, it's ...

  18. The Air Solar Collectors: Introduction of Chicanes to Favour the Heat Transfer and Temperature in the Air Stream Dynamics

    Directory of Open Access Journals (Sweden)

    Mahfoud Omar

    2015-01-01

    Full Text Available The thermal performance of a single pass solar air heater with chicanes attached was investigated numerically using a 2D model of solar air stream dynamics collectors where the turbulence standard (k-ε model has been implemented. The chicane is formed with two parts: the first is perpendicular to the air flow and the second part is titled (α, they are mounted in successive rows, oriented perpendicular to the air flow and soldered to the back plate. The predicted results are validated by comparing with the literatures semi-empirical and experimental data and shown a reasonable agreement. Effects of relevant parameters as the (Reynolds number, chicanes upper parts tilts angles and air mass flow rates on the heat transfer coefficient and temperature development are discussed. It is apparent that the turbulence created by the chicanes resulting in greater increase in heat transfer inside the air stream dynamics.

  19. Presentation of an innovative and efficient air conditioning system for electrical powered vehicles; Vorstellung eines innovativen und effizienten Klimasystems fuer elektrisch angetriebene Fahrzeuge

    Energy Technology Data Exchange (ETDEWEB)

    Kaplan, Oleg [IAV GmbH, Muenchen (Germany); Ackermann, Jan; Fang, Fang [IAV GmbH, Gifhorn (Germany)

    2012-11-01

    An air-conditioning system for battery electric vehicles requires an efficient approach to provide heat and cool during operation in winter and summer. The required energy expenditure to ensure comfort and safety is enormous especially during the winter. The heat input into the cabin amounts up to 10 kW and above when considering conventional vehicles with an internal combustion engine. In this context IAV is developing an efficient overall air conditioning system. The combination of new system components, such as surface heaters and a heat pump with improved components such as a PTC-heater, can solve the discrepancy between acceptable range and the aspects of comfort and safety. (orig.)

  20. Molecular hydrogen (H2 combustion emissions and their isotope (D/H signatures from domestic heaters, diesel vehicle engines, waste incinerator plants, and biomass burning

    Directory of Open Access Journals (Sweden)

    T. Röckmann

    2012-03-01

    Full Text Available Molecular hydrogen (H2, its stable isotope signature (δD, and the key combustion parameters carbon monoxide (CO, carbon dioxide (CO2, and methane (CH4 were measured from various combustion processes. H2 in the exhaust of gas and oil-fired heaters and of waste incinerator plants was generally depleted compared to ambient intake air, while CO was significantly elevated. These findings contradict the often assumed co-occurring net H2 and CO emissions in combustion processes and suggest that previous H2 emissions from combustion may have been overestimated when scaled to CO emissions. For the heater exhausts, H2 and δD generally decrease with increasing fuel-to-air ratio, from ambient values of ∼0.5 ppm and +130‰ to 0.2 ppm and −206‰, respectively. These results are interpreted as a combination of an isotopically light H2 source from fossil fuel combustion and a D/H kinetic isotope fractionation of hydrogen in the advected ambient air during its partial removal during combustion. Diesel exhaust measurements from dynamometer test stand driving cycles show elevated H2 and CO emissions during cold-start and some acceleration phases. Their molar H2/CO ratios are 2/CO emission ratios, along with CO global emission inventories, we estimate global H2 emissions for 2000, 2005, and 2010. For road transportation (gasoline and diesel, we calculate 8.6 ± 2.1 Tg, 6.3 ± 1.5 Tg, and 4.1 ± 1.0 Tg, respectively, whereas the contribution from diesel vehicles has increased from 5% to 8% over this time. Other fossil fuel emissions are believed to be negligible but H2 emissions from coal combustion are unknown. For residential (domestic emissions, which are likely dominated by biofuel combustion, emissions for the same years are estimated at 2.7 ± 0.7 Tg, 2.8 ± 0.7 Tg, and 3.0 ± 0.8 Tg, respectively. Our wood combustion measurements are combined with results from the literature to calculate biomass burning emissions. For these estimates, we propose a

  1. Intelligence on the second stage. 'Air-On' plus air/water heat pump. Cheap air conditioning technology; Intelligenz der zweiten Stufe. 'Air-On' plus Luft/Wasser-Waermepumpe. Preiswerte Raumklimatechnik

    Energy Technology Data Exchange (ETDEWEB)

    Genath, Bernd

    2011-07-15

    It is hard to believe: The heating technique still holds thoughtful surprises. Based on the idea and based on the physics of the heating technology, the company Air-On AG (Cham, Switzerland). For the renovation of old buildings, this company used a second stage of a heat pump to replace old heaters. This second stage is a Peltier element and exclusively tempers a individual room decentrally. The second stage has a better coefficiency of performance than the first stage such as an air / water heat pump.

  2. Large refinery and petrochemical plant furnaces and heaters : low frequency noise measurement and noise source order-ranking

    Energy Technology Data Exchange (ETDEWEB)

    Leslie Frank, HFP Acoustical Consultants Corp. Calgary AB

    2007-07-01

    Large furnaces and process heaters at refineries, gas plants, and petrochemical plants produce a low-frequency tonal noise from combustion roar. They can also produce mid-frequency broadband noise from induced draft fans. The common noise generating mechanisms are turbulence, flow instability, pressure drop, mechanical friction, and component vibration. Some of these energy facilities have multiple furnaces and heaters. As such, a noise source order-ranking assessment is typically performed to determine which plant equipment is responsible for the highest sound level contributions at nearby residence locations. The order-ranking is useful in determining which noise sources may require acoustical treatment to reduce the overall sound level at each residence. These results would form the basis for evaluating the effect of noise mitigating strategies for each source, and for estimating the associated costs for each noise control scenario. The noise model results can also be used to order-rank the equipment noise sources in terms of their frequency-dependant octave band. Experience has shown that large furnaces and heaters usually rank very high in terms of predominant contributors. The combustion roar noise generating mechanism is largely responsible for the predominant amount of acoustical energy. Although some degree of noise reduction can be achieved through burner design, it was shown that noise control engineering largely occurs at the furnace and heater manufacturing or plant retrofit level. This paper presented the results of one refinery with 19 older style furnaces and heaters. 1 tab., 7 figs.

  3. Development of an Operation Control System for Photovoltaics and Electric Storage Heaters for Houses Based on Information in Weather Forecasts

    Science.gov (United States)

    Obara, Shin'ya

    An all-electric home using an electric storage heater with safety and cleaning is expanded. However, the general electric storage heater leads to an unpleasant room temperature and energy loss by the overs and shorts of the amount of heat radiation when the climate condition changes greatly. Consequently, the operation of the electric storage heater introduced into an all-electric home, a storage type electric water heater, and photovoltaics was planned using weather forecast information distributed by a communication line. The comfortable evaluation (the difference between a room-temperature target and a room-temperature result) when the proposed system was employed based on the operation planning, purchase electric energy, and capacity of photovoltaics was investigated. As a result, comfortable heating operation was realized by using weather forecast data; furthermore, it is expected that the purchase cost of the commercial power in daytime can be reduced by introducing photovoltaics. Moreover, when the capacity of the photovoltaics was increased, the surplus power was stored in the electric storage heater, but an extremely unpleasant room temperature was not shown in the investigation ranges of this paper. By obtaining weather information from the forecast of the day from an external service using a communication line, the heating system of the all-electric home with low energy loss and comfort temperature is realizable.

  4. The Epidemiology of Emergency Department-Treated Burn Injuries Associated with Portable Heaters in the United States, 2003-2013.

    Science.gov (United States)

    Brooks, Raina D; McGwin, Gerald

    The purpose of this study is to examine the epidemiology of portable space heater-related burn injuries among an emergency department nationally representative population of the United States. The data analyzed in this study were collected from the Consumer Products Safety Commission's 2003-2013 National Electronic Injury Surveillance System. There were approximately 53,636 space heater-related thermal burn injuries attributed to portable space heaters from 2003 to 2013. The rate of injuries was relatively constant during the 10-year span. The number of burn injuries was highest during winter months. Young children, older adults, males, and Blacks had the highest rates of injury. The body part most commonly injured was the hand, which accounted for 33.3% of all burn injuries. It is important to understand the characteristics of persons who have an increased risk of portable space heater burn and trip/fall injuries, so that preventative methods and awareness strategies can be used to help reduce the number of annual portable space heater injuries.

  5. Molecular Sieve Steam Heater Leak Accident and Processing%分子筛蒸汽加热器泄露事故及处理

    Institute of Scientific and Technical Information of China (English)

    陈庆山

    2015-01-01

    Air separation plant molecular sieve column system for steam heater tube material causes leakage problem, steam runs into the dirty side of nitrogen, makes exceed carbon in the analysis of molecular sieve export while the molecular sieve regenerate, causes heat exchanger inside cold box“ice block” unsustainable system load, and affects the normal operation of air separation and after system. The accident treatment process, cause analysis, specific methods and steps of accident prevention were introduced.%空分装置分子筛系统因蒸汽加热器列管材质问题导致泄露,蒸汽进入污氮气侧使分子筛再生时无法达到指标,分子筛出口二氧化碳分析超标,造成冷箱内换热器“冰堵”系统负荷无法维持,影响了空分及后系统的正常运行,详细介绍了事故处理过程,原因分析,事故预防的具体方法和步骤。

  6. Analysis of a Permanent Magnet Eddy Current Heater Driven by a Wind Turbine

    Directory of Open Access Journals (Sweden)

    TUDORACHE, T.

    2015-08-01

    Full Text Available This paper deals with the numerical analysis and optimal design of a Permanent Magnet Eddy Current Heater (PMECH driven by a wind turbine. This study includes a preliminary sizing of the wind turbine, an optimal design of the PMECH from cost reduction point of view, a heat transfer analysis of the device and a study of the dynamic response of the wind system. The electromagnetic and heat transfer analysis is based on Finite Element Method (FEM implemented in the Flux software package and the dynamic response of the wind system is analyzed using a dedicated model developed under Matlab/Simulink environment.

  7. One-heater flow-through polymerase chain reaction device by heat pipes cooling.

    Science.gov (United States)

    Chen, Jyh Jian; Liao, Ming Huei; Li, Kun Tze; Shen, Chia Ming

    2015-01-01

    This study describes a novel microfluidic reactor capable of flow-through polymerase chain reactions (PCR). For one-heater PCR devices in previous studies, comprehensive simulations and experiments for the chip geometry and the heater arrangement were usually needed before the fabrication of the device. In order to improve the flexibility of the one-heater PCR device, two heat pipes with one fan are used to create the requisite temperature regions in our device. With the integration of one heater onto the chip, the high temperature required for the denaturation stage can be generated at the chip center. By arranging the heat pipes on the opposite sides of the chip, the low temperature needed for the annealing stage is easy to regulate. Numerical calculations and thermal measurements have shown that the temperature distribution in the five-temperature-region PCR chip would be suitable for DNA amplification. In order to ensure temperature uniformity at specific reaction regions, the Re of the sample flow is less than 1. When the microchannel width increases and then decreases gradually between the denaturation and annealing regions, the extension region located in the enlarged part of the channel can be observed numerically and experimentally. From the simulations, the residence time at the extension region with the enlarged channel is 4.25 times longer than that without an enlarged channel at a flow rate of 2 μl/min. The treated surfaces of the flow-through microchannel are characterized using the water contact angle, while the effects of the hydrophilicity of the treated polydimethylsiloxane (PDMS) microchannels on PCR efficiency are determined using gel electrophoresis. By increasing the hydrophilicity of the channel surface after immersing the PDMS substrates into Tween 20 (20%) or BSA (1 mg/ml) solutions, efficient amplifications of DNA segments were proved to occur in our chip device. To our knowledge, our group is the first to introduce heat pipes into

  8. Reliable, Economic, Efficient CO2 Heat Pump Water Heater for North America

    Energy Technology Data Exchange (ETDEWEB)

    Radcliff, Thomas D; Sienel, Tobias; Huff, Hans-Joachim; Thompson, Adrian; Sadegh, Payman; Olsommer, Benoit; Park, Young

    2006-12-31

    Adoption of heat pump water heating technology for commercial hot water could save up to 0.4 quads of energy and 5 million metric tons of CO2 production annually in North America, but industry perception is that this technology does not offer adequate performance or reliability and comes at too high of a cost. Development and demonstration of a CO2 heat pump water heater is proposed to reduce these barriers to adoption. Three major themes are addressed: market analysis to understand barriers to adoption, use of advanced reliability models to design optimum qualification test plans, and field testing of two phases of water heater prototypes. Market experts claim that beyond good performance, market adoption requires 'drop and forget' system reliability and a six month payback of first costs. Performance, reliability and cost targets are determined and reliability models are developed to evaluate the minimum testing required to meet reliability targets. Three phase 1 prototypes are designed and installed in the field. Based on results from these trials a product specification is developed and a second phase of five field trial units are built and installed. These eight units accumulate 11 unit-years of service including 15,650 hours and 25,242 cycles of compressor operation. Performance targets can be met. An availability of 60% is achieved and the capability to achieve >90% is demonstrated, but overall reliability is below target, with an average of 3.6 failures/unit-year on the phase 2 demonstration. Most reliability issues are shown to be common to new HVAC products, giving high confidence in mature product reliability, but the need for further work to minimize leaks and ensure reliability of the electronic expansion valve is clear. First cost is projected to be above target, leading to an expectation of 8-24 month payback when substituted for an electric water heater. Despite not meeting all targets, arguments are made that an industry leader could

  9. Arc-Heater Facility for Hot Hydrogen Exposure of Nuclear Thermal Rocket Materials

    Science.gov (United States)

    Litchford, Ron J.; Foote, John P.; Wang,Ten-See; Hickman, Robert; Panda, Binayak; Dobson, Chris; Osborne, Robin; Clifton, Scooter

    2006-01-01

    A hyper-thermal environment simulator is described for hot hydrogen exposure of nuclear thermal rocket material specimens and component development. This newly established testing capability uses a high-power, multi-gas, segmented arc-heater to produce high-temperature pressurized hydrogen flows representative of practical reactor core environments and is intended to serve. as a low cost test facility for the purpose of investigating and characterizing candidate fueUstructura1 materials and improving associated processing/fabrication techniques. Design and development efforts are thoroughly summarized, including thermal hydraulics analysis and simulation results, and facility operating characteristics are reported, as determined from a series of baseline performance mapping tests.

  10. Chalcogenide Random Access Memory Cell with Structure of W Sub-Microtube Heater Electrode

    Institute of Scientific and Technical Information of China (English)

    LIU Bo; FENG Gao-Ming; WU Liang-Cai; SONG Zhi-Tang; LIU Qi-Bin; FENG Song-Lin; CHEN Bomy

    2007-01-01

    @@ In order to reduce the reset current of chalcogenide random access memory, a W sub-microtube heater electrode with outer/inner diameter of 260/100nm, which was fabricated with standard 0.18-μm technology, is proposed for the first time to achieve a reset current of about 0.5mA. The reasons may be that sub-microtube increases the number of electrode edge and thermal efficiency is improved greatly because the thermal density on the edge of sub-microtube electrode is generally the highest.

  11. 直热式热泵热水器冷凝器结构优化试验研究%Experimental Research on Structure Optimization of Condenser of Directly-heated Type Heat-pump Water Heater

    Institute of Scientific and Technical Information of China (English)

    毛瑞萍

    2015-01-01

    搭建了空气源热泵热水器试验台。在标准工况下,分别比较了普通套管式冷凝器,3套管式冷凝器和板式冷凝器对热泵系统运行性能的影响。结果表明,板式换热器在热泵热水器系统中换热性能大大优于另外两种常规换热器,其性能系数达到4.1,比使用其他两种冷凝器性能系数提高20%左右。试验结果为如何提高热泵热水器性能提供了依据。%The air source heat pump water heater test rig was set up. Under the standard operating conditions, the influence of the ordinary casing type condenser, the 3 tube condenser and the plate condenser on the operating perfor-mance of the heat pump system are compared. The results show that the plate heat exchanger in heat pump water heater system in heat transfer performance is much better than other two conventional heat exchangers. Its coefficient of per-formance reached 4.1, which higher than the performance coefficient of other two condensers increased by about 20%. The experimental results provided the basis for improving the performance of the heat pump water heater.

  12. Micro Ethanol Sensors with a Heater Fabricated Using the Commercial 0.18 μm CMOS Process

    Directory of Open Access Journals (Sweden)

    Wei-Zhen Liao

    2013-09-01

    Full Text Available The study investigates the fabrication and characterization of an ethanol microsensor equipped with a heater. The ethanol sensor is manufactured using the commercial 0.18 µm complementary metal oxide semiconductor (CMOS process. The sensor consists of a sensitive film, a heater and interdigitated electrodes. The sensitive film is zinc oxide prepared by the sol-gel method, and it is coated on the interdigitated electrodes. The heater is located under the interdigitated electrodes, and it is used to supply a working temperature to the sensitive film. The sensor needs a post-processing step to remove the sacrificial oxide layer, and to coat zinc oxide on the interdigitated electrodes. When the sensitive film senses ethanol gas, the resistance of the sensor generates a change. An inverting amplifier circuit is utilized to convert the resistance variation of the sensor into the output voltage. Experiments show that the sensitivity of the ethanol sensor is 0.35 mV/ppm.

  13. Research and Design of a Sample Heater for Beam Line 6-2c Transmission X-ray Microscope

    Energy Technology Data Exchange (ETDEWEB)

    Policht, Veronica; /Loyola U., Chicago /SLAC

    2012-08-27

    There exists a need for environmental control of samples to be imaged by the Transmission X-Ray Microscope (TXM) at the SSRLs Beam Line 6-2c. In order to observe heat-driven chemical or morphological changes that normally occur in situ, microscopes require an additional component that effectively heats a given sample without heating any of the microscope elements. The confinement of the heat and other concerns about the heaters integrity limit which type of heater is appropriate for the TXM. The bulk of this research project entails researching different heating methods used previously in microscopes, but also in other industrial applications, with the goal of determining the best-fitting method, and finally in designing a preliminary sample heater.

  14. Letter Report. Defense Waste Processing Facility Pour Spout Heaters - Conceptual Designs and Modeling

    Energy Technology Data Exchange (ETDEWEB)

    SK Sundaram; JM Perez, Jr.

    2000-09-06

    The Tanks Focus Area (TFA) identified a major task to address performance limitations and deficiencies of the Defense Waste Processing Facility (DWPF) now in its sixth year of operation. Design, installation, testing, monitoring, operability, and a number of other characteristics were studied by research personnel collaboratively at a number of facilities: Savannah River Technology Center (SRTC), Clemson Environmental Technologies Laboratory (CETL), Pacific Northwest National Laboratory (PNNL), and the Idaho National Engineering and Environmental Laboratory (INEEL). Because the potential limiting feature to the DWPF was identified as the pour spout/riser heater, researches on alternative design concepts originally proposed in the past were revisited. In the original works, finite element modeling was performed to evaluate temperature distribution and stress of the design currently used at the DWPF. Studies were also made to define the requirements of the design and to consider the approaches for remote removal/replacement. Their heater type/location, their remotely replaceable thermocouples, and their capabilities for remote handling characterized the five alternative designs proposed. Review comments on the alternative designs indicated a relatively wide range of advantages and disadvantages of the designs. The present report provides an overview of the design criteria, modeling results, and alternative designs. Based on a review of the past design optimization activities and an assessment of recent experience, recommendations are proposed for future consideration and improvement.

  15. Solar heaters, should they be seen or not?; Calentadores solares, mostrarlos u ocultarlos?

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Martinez, Octavio [Modulo Solar, S.A. de C.V., Cuernavaca, Morelos (Mexico)

    2000-07-01

    Talking about Solar Heaters, architects have two opposite points of view about aesthetics. Some architects are convinced that the collector field should be integrated into the original design or in buildings already built, these fields should be adapted and fully shown. On the other hand, there are those who prefer collectors not to be seen. This work, based on our experience since 1975, will show with photographOut experience since 1975 will be show with solutions that have satisfy each part. With worldwide expectations of massive use of solar energy in the first decade of the millennium, we think that is important to discuss whether: SOLAR HEATERS, should they be seen or not?. [Spanish] Con respecto a los aspectos esteticos de los equipos solares, en el medio arquitectonico existen dos corrientes plenamente contrapuestas: 1.- Aquellos que estan convencidos que hay que integrar los campos de colectores al diseno original o que hay que resolver en las edificaciones existentes la adaptacion de los mismos mostrandolos plenamente y 2.- Aquellos que prefieren ocultarlos. En este trabajo, basado en experiencias desde 1975, mostrara, mediante imagenes, ejemplos de soluciones que hay satisfecho a cada corriente. Con las expectativas mundiales del uso masivo de la energia solar en la primera decada del milenio, seria importante, de una buena vez, encauzar la polemica: EQUIPOS SOLARES SE DEBEN VER O NO?.

  16. Impact of Pilot Light Modeling on the Predicted Annual Performance of Residential Gas Water Heaters: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Maguire, J.; Burch, J.

    2013-08-01

    Modeling residential water heaters with dynamic simulation models can provide accurate estimates of their annual energy consumption, if the units? characteristics and use conditions are known. Most gas storage water heaters (GSWHs) include a standing pilot light. It is generally assumed that the pilot light energy will help make up standby losses and have no impact on the predicted annual energy consumption. However, that is not always the case. The gas input rate and conversion efficiency of a pilot light for a GSWH were determined from laboratory data. The data were used in simulations of a typical GSWH with and without a pilot light, for two cases: 1) the GSWH is used alone; and 2) the GSWH is the second tank in a solar water heating (SWH) system. The sensitivity of wasted pilot light energy to annual hot water use, climate, and installation location was examined. The GSWH used alone in unconditioned space in a hot climate had a slight increase in energy consumption. The GSWH with a pilot light used as a backup to an SWH used up to 80% more auxiliary energy than one without in hot, sunny locations, from increased tank losses.

  17. MATHEMATICAL MODELLING OF PREFERED SOLUTIONS CHOICE FUNCTION FOR TUBULAR GAS HEATERS BY EXPERIMENTAL INFORMATIONS

    Directory of Open Access Journals (Sweden)

    BARSUK R. V.

    2016-08-01

    Full Text Available Annotation. Problems formulation. The article deals with choice functions building of preferred solutions by experimental information for tubular gas heater working on fuel granules - pellets.Further choice functions using for making technical solutions by tubular gas heaters construction and designing. Recently research analysis. There are works about choice functions construction by separate presents are examined. But full chose functions building by separate presents are not examined. Aims and tasks. There are setting aim to develop full choice functions mathematical model on separate presents by authors. The expert are connect to primary experimental data’s evaluation that estimates separate results by output functions (criteria. Its evaluations issue in experimental points paired comparison’s table form. Thus, there are necessary construct binary choice relations presents on experimental “points” set by expert that then using for full choice function’s constructing. Conclusions. There are choice function’s construction’s sequence are sets. There are posed point comparison results that characterized tubular gas heater’s condition with expert’s evaluation using. Also posed output functions comparisons by which can be characterized improving tubular gas heater’s performance or vice versa.

  18. Scheduling of Domestic Water Heater Power Demand for Maximizing PV Self-Consumption Using Model Predictive Control

    DEFF Research Database (Denmark)

    Sossan, Fabrizio; Kosek, Anna Magdalena; Martinenas, Sergejus

    2013-01-01

    This paper presents a model predictive control (MPC) strategy for maximizing photo-voltaic (PV) selfconsumption in a household context exploiting the flexible demand of an electric water heater. The predictive controller uses a water heater model and forecast of the hot Water consumption in order...... to predict the future temperature of the water and it manages its state (on and off) according to the forecasted PV production, which are computed starting from forecast of the solar irradiance. Simulations for the proof of concept and for validating the proposed control strategy are proposed. Results...

  19. Unsteady mixed convection in a porous media filled lid-driven cavity heated by a semi-circular heaters

    Directory of Open Access Journals (Sweden)

    Rahman M.M.

    2015-01-01

    Full Text Available A computational study has been performed on natural convection heat transfer and fluid flow in a porous media filled enclosure with semi-circular heaters by using finite element method. The ceiling of the cavity moves with a constant velocity and it is insulated. Temperature of vertical walls is lower than that of heaters. Results are presented via streamlines, isotherms, average Nusselt numbers and cross sectional velocity for different governing parameters such as Richardson number, Darcy number and dimensionless time. It is observed that both circulation of the flow and heat transfer is strongly affected with time increment and Darcy number inside the cavity.

  20. Examination and evaluation of the use of screen heaters for the measurement of the high temperature pyrolysis kinetics of polyethene and polypropene.

    NARCIS (Netherlands)

    Westerhout, R.W.J.; Balk, R.H.P.; Meijer, R.; Kuipers, J.A.M.; Swaaij, van W.P.M.

    1997-01-01

    A screen heater with a gas sweep was developed and applied to study the pyrolysis kinetics of low density polyethene (LDPE) and polypropene (PP) at temperatures ranging from 450 to 530 C. The aim of this study was to examine the applicability of screen heaters to measure these kinetics. On-line meas

  1. Building America Case Study: Heat Pump Water Heater Ducting Strategies with Encapsulated Attics in Climate Zones 2 and 4, LaFayette, Georgia (CZ4), and Savannah, Georgia (CZ2)

    Energy Technology Data Exchange (ETDEWEB)

    2017-02-01

    The focus of this study is on the performance of HPWHs with several different duct configurations and their effects on whole building heating, cooling, and moisture loads. A.O. Smith 60 gallon Voltex (PHPT-60) heat pump water heaters (HPWHs) were included at two project sites and ducted to or located within spray foamed encapsulated attics. The effect of ducting a HPWH's air stream does not diminish its efficiency if the ducting does not reduce intake air temperature, which expands HPWH application to confined areas. Exhaust ducts should be insulated to avoid condensation on the exterior, however this imposes a risk of condensation occurring in the duct's interior near the HPWH due to large variation of temperatures between the compressor and the duct and the presence of bulk moisture around the condenser. The HPWH's air conditioning impact on HVAC equipment loads is minimal when the intake and exhaust air streams are connected to a sealed attic and not the living space. A HPWH is not suitable as a replacement dehumidifier in sealed attics as peak moisture loads were observed to only be reduced if the heat pump operated during the morning. It appears that the intake air temperature and humidity was the most dominant variable affecting HPWH performance. Different ducting strategies such as exhaust duct only, intake duct only, and exhaust and intake ducting did not have any effect on HPWH performance.

  2. Design of Control System of Parallel Solar Assisted Heat Pump Water Heater%并联式太阳能热泵热水器控制系统设计

    Institute of Scientific and Technical Information of China (English)

    张建成; 吴永明; 苗文凭

    2012-01-01

    阐述了并联式太阳热泵热水器是最易受推广使用的太阳能热泵热水器类型;针对23目前并联式太阳能热泵热水器存在的集成化控制问题,分析了并联式太阳热泵热水器控制系统的控制要求,采用水位、温差与时间相结合的控制方法,以ATmega48单片机为核心,研究了控制系统的工作原理、硬件结构及控制数据流程;系统能够根据天气、水温等不同情况自动选择太阳能机组或空气能热泵机组来制取热水,并且具有主要设备的故障自诊断功能、压缩机延时保护功能及智能化霜功能,提高了该热水器的稳定性和低温制热效率;测试结果表明:使用该集成系统后,系统平均能源利用率提高了约23%.%Among all the solar assisted heat pump water heater, the paralle type is the most easily promoted. According to the integrated problem that exists in the control of the parallel solar assisted heat pump water heater, on the basis of analyzing requirements of the control system of the parallel solar assisted heat pump water heater, the control method associating with water-level, difference in temperature and time is applied. The realization principle, hardware structure and controlling data flow of the control system are studied based on AT-mega48. The system can select automatically solar-energy or air-energy heat -pump to make hot water according to weather and water temperature. Combined with the functions of fault self -diagnosis for key facilities, delay protection for compressor and automatically defrosting, the control system can improve the stability and thermal efficiency of the water heater under the low temperature. The results show that 23%of the average energy efficiency have been improved by using the integrated control system.

  3. Understanding the mechanisms leading to failure in metallic nanowire-based transparent heaters, and solution for stability enhancement

    Science.gov (United States)

    Lagrange, M.; Sannicolo, T.; Muñoz-Rojas, D.; Guillo Lohan, B.; Khan, A.; Anikin, M.; Jiménez, C.; Bruckert, F.; Bréchet, Y.; Bellet, D.

    2017-02-01

    Silver nanowire (AgNW) networks are emerging as one of the most promising alternatives to indium tin oxide (ITO) for transparent electrodes in flexible electronic devices. They can be used in a variety of optoelectronic applications such as solar cells, touch panels and organic light-emitting diodes. Recently they have also proven to be very efficient when used as transparent heaters (THs). In addition to the study of AgNW networks acting as THs in regular use, i.e. at low voltage and moderate temperature, their stability and physical behavior at higher voltages and for longer durations should be studied in view of their integration into real devices. The properties of AgNW networks deposited by spray coating on glass or flexible transparent substrates are thoroughly studied via in situ measurements. The AgNW networks’ behavior at different voltages for different durations and under different atmospheric conditions, both in air and under vacuum, has been examined. At low voltage, a reversible electrical response is observed while irreversibility and even failure are observed at higher voltages. In order to gain a deeper insight into the behavior of AgNW networks used as THs, simple but realistic physical models are proposed and are found to be in fair agreement with the experimental data. Finally, as the stability of AgNW networks is a key issue, we demonstrate that coating AgNW networks with a very thin layer of TiO2 using atomic layer deposition (ALD) improves the material’s resistance against electrical and thermal instabilities without altering optical transmittance. We show that the critical annealing temperature associated to network breakdown increases from 270 °C for the as-deposited AgNW networks to 420 °C for AgNW networks coated with TiO2. Similarly, the electrical failure which occurs at 7 V for the as-deposited networks increases to 13 V for TiO2-coated networks. TiO2 is also proved to stabilize AgNW networks during long duration operation and at

  4. Understanding the mechanisms leading to failure in metallic nanowire-based transparent heaters, and solution for stability enhancement.

    Science.gov (United States)

    Lagrange, M; Sannicolo, T; Muñoz-Rojas, D; Lohan, B Guillo; Khan, A; Anikin, M; Jiménez, C; Bruckert, F; Bréchet, Y; Bellet, D

    2017-02-03

    Silver nanowire (AgNW) networks are emerging as one of the most promising alternatives to indium tin oxide (ITO) for transparent electrodes in flexible electronic devices. They can be used in a variety of optoelectronic applications such as solar cells, touch panels and organic light-emitting diodes. Recently they have also proven to be very efficient when used as transparent heaters (THs). In addition to the study of AgNW networks acting as THs in regular use, i.e. at low voltage and moderate temperature, their stability and physical behavior at higher voltages and for longer durations should be studied in view of their integration into real devices. The properties of AgNW networks deposited by spray coating on glass or flexible transparent substrates are thoroughly studied via in situ measurements. The AgNW networks' behavior at different voltages for different durations and under different atmospheric conditions, both in air and under vacuum, has been examined. At low voltage, a reversible electrical response is observed while irreversibility and even failure are observed at higher voltages. In order to gain a deeper insight into the behavior of AgNW networks used as THs, simple but realistic physical models are proposed and are found to be in fair agreement with the experimental data. Finally, as the stability of AgNW networks is a key issue, we demonstrate that coating AgNW networks with a very thin layer of TiO2 using atomic layer deposition (ALD) improves the material's resistance against electrical and thermal instabilities without altering optical transmittance. We show that the critical annealing temperature associated to network breakdown increases from 270 °C for the as-deposited AgNW networks to 420 °C for AgNW networks coated with TiO2. Similarly, the electrical failure which occurs at 7 V for the as-deposited networks increases to 13 V for TiO2-coated networks. TiO2 is also proved to stabilize AgNW networks during long duration operation and at

  5. Vol. 34 - Optimization of quench protection heater performance in high-field accelerator magnets through computational and experimental analysis

    CERN Document Server

    Salmi, Tiina

    2016-01-01

    Superconducting accelerator magnets with increasingly hi gh magnetic fields are being designed to improve the performance of the Large Hadron Collider (LHC) at CERN. One of the technical challenges is the magnet quench p rotection, i.e., preventing damage in the case of an unexpected loss of superc onductivity and the heat generation related to that. Traditionally this is d one by disconnecting the magnet current supply and using so-called protection he aters. The heaters suppress the superconducting state across a large fraction of the winding thus leading to a uniform dissipation of the stored energy. Preli minary studies suggested that the high-field Nb 3 Sn magnets under development for the LHC luminosity upgrade (HiLumi) could not be reliably protected using the existing heaters. In this thesis work I analyzed in detail the present state-of-the-art protection heater technology, aiming to optimize its perfo rmance and evaluate the prospects in high-field magnet protection. The heater efficiency analyses ...

  6. Experimental validation of dynamic simulation of the flat plate collector in a closed thermosyphon solar water heater

    DEFF Research Database (Denmark)

    Taherian, H.; Kolaei, Alireza Rezania; Sadeghi, S.;

    2011-01-01

    This work studies the dynamic simulation of thermosyphon solar water heater collector considering the weather conditions of a city in north of Iran. The simulation was done for clear and partly cloudy days. The useful energy, the efficiency diagrams, the inlet and the outlet of collector, center...

  7. 10 CFR Appendix P to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Pool Heaters

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Uniform Test Method for Measuring the Energy Consumption of Pool Heaters P Appendix P to Subpart B of Part 430 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS Test Procedures Pt. 430, Subpt. B, App. P Appendix P...

  8. Theoretical heating coefficient of a heat pump water heater with heat recovery applied in household bathing room

    Institute of Scientific and Technical Information of China (English)

    KOUGuangxiao; WANGHanqing; GUWeili; KOUJianguo

    2003-01-01

    Presents the components and flow diagram of a heat pump water heater with heat reclaim applied In household bathing room, analyzes its characteristics from thermodynamical principle, calculates its theoretical heating coefficient under different operating conditions. The result shows that the maximum value of its heating coefficient is 12.9 under a typical operating condition.

  9. Improved electrothermal performance of custom-shaped micro heater based on anisotropic laser-reduced graphene oxide

    Science.gov (United States)

    Zhang, Tian-Yu; Zhao, Hai-Ming; Yang, Zhen; Wang, Qian; Wang, Dan-Yang; Deng, Ning-Qin; Yang, Yi; Ren, Tian-Ling

    2016-10-01

    In this paper, a flexible heater based on anisotropic laser-reduced graphene oxide (LRGO) is established. Attributing to precision and shape design of laser processing and excellent adhesion of graphene oxide, the LRGO-based heater can be microminiaturized with custom patterns and integrated on various substrates, which is what the existing film heaters cannot do and can be widely used for wearable heating devices, flexural warming systems in medical science, and light deicing equipment and heaters for aero vehicles. The electrothermal performance of the anisotropic LRGO is investigated systematically through a series of experiments including Raman spectra, SEM, white-light interferograms, IV testing, and infrared thermography. The electrothermal performance of the LRGO with the parallel aligned direction is better than the LRGO with the vertical aligned direction. The electrothermal performance can be improved greatly through radiating repeatedly. The saturated temperature and heating rate of the LRGO radiated twice are almost double that of the LRGO radiated once. Radiating thrice damages the material and structure, reducing electrothermal performance.

  10. Long-Term Creep of a Thin-Walled Inconel 718 Stirling Power-Convertor Heater Head Assessed

    Science.gov (United States)

    Bowman, Randy R.

    2002-01-01

    The Department of Energy and NASA have identified Stirling power convertors as candidate power supply systems for long-duration, deep-space science missions. A key element for qualifying the flight hardware is a long-term durability assessment for critical hot section components of the power convertor. One such critical component is the power convertor heater head. The heater head is a high-temperature pressure vessel that transfers heat to the working gas medium of the convertor, which is typically helium. An efficient heater head design is the result of balancing the divergent requirements of thin walls for increased heat transfer versus thick walls to lower the wall stresses and thus improve creep resistance and durability. In the current design, the heater head is fabricated from the Ni-base superalloy Inconel 718 (IN 718, Inco Alloys International, Inc., Huntington, WV). Although IN 718 is a mature alloy system (patented in 1962), there is little long-term (>50,000-hr) creep data available for thin-specimen geometries. Since thin-section properties tend to be inferior to thicker samples, it is necessary to generate creep data using specimens with the same geometry as the actual flight hardware. Therefore, one facet of the overall durability assessment program involves generating relatively short-term creep data using thin specimens at the design temperature of 649 C (1200 F).

  11. Exergy analysis of integrated photovoltaic thermal solar water heater under constant flow rate and constant collection temperature modes

    NARCIS (Netherlands)

    Tiwari, Arvind; Dubey, Swapnil; Sandhu, G.S.; Sodha, M.S.; Anwar, S.I.

    2009-01-01

    In this communication, an analytical expression for the water temperature of an integrated photovoltaic thermal solar (IPVTS) water heater under constant flow rate hot water withdrawal has been obtained. Analysis is based on basic energy balance for hybrid flat plate collector and storage tank, resp

  12. Benchmark of CFD Simulations Using Temperatures Measured Within an Enclosed Array of Heater Rods Oriented Vertically and Horizontally

    Science.gov (United States)

    Chalasani, Narayana Rao

    Experiments and computational fluid dynamics/radiation heat transfer simulations of an 8x8 array of heated rods within an aluminum enclosure are performed. This configuration represents a region inside the channel of a spent boiling water reactor (BWR) fuel assembly between two consecutive spacer plates. The heater rods can be oriented horizontally or vertically to represent transport or storage conditions, respectively. The measured and simulated rod-to-wall temperature differences are compared for various heater rod power levels (100, 200, 300, 400 and 500W), gases (Helium and Nitrogen), enclosure wall temperatures, pressures (1, 2 and 3 atm) and orientations (Horizontal and Vertical) to assess the accuracy of the computational fluid dynamics (CFD) code. For analysis of spent nuclear fuel casks, it is crucial to predict the temperature of the hottest rods in an assembly to ensure that none of the fuel cladding exceeds its temperature limit. The measured temperatures are compared to those determined using CFD code to assess the adequacy of the computer code. Simulations show that temperature gradients are much steeper near the enclosure walls than they are near the center of the heater rod array. The measured maximum heater rod temperatures are above the center of heater rod array for nitrogen experiments in both horizontal and vertical orientations, whereas for helium the maximum temperatures are at the center of heater rod array irrespective of the orientation due to the high thermal conductivity of the helium gas. The measured temperatures of rods at symmetric locations are not identical, and the difference is larger for rods close to the enclosure wall than for those far from it. Small but uncontrolled deviations of the rod positions away from the design locations may cause these differences. For 2-inch insulated nitrogen experiment in vertical orientation with 1 atm pressure and a total heater rod power of 500 W, the maximum measured heater rod and enclosure

  13. Characteristics of indoor radon and its progeny in a Japanese dwelling while using air appliances.

    Science.gov (United States)

    Pornnumpa, C; Tokonami, S; Sorimachi, A; Kranrod, C

    2015-11-01

    Characteristics of radon and its progeny were investigated in different air conditions by turning four types of indoor air appliances on and off in a two-story concrete Japanese dwelling. The four appliances were air conditioner, air cleaner, gas heater and cooker hood. The measurements were done using two devices: (1) a Si-based semiconductor detector for continuous measurement of indoor radon concentration and (2) a ZnS(Ag) scintillation counting system for equilibrium-equivalent radon concentration. Throughout the entire experiment, the cooker hood was the most effective in decreasing indoor radon concentration over a long period of time and the less effective was the air conditioner, while the air cleaner and gas heater did not affect the concentration of radon. However, the results measured in each air condition will differ according to the lifestyles and activities of the inhabitants. In this study, indoor radon and its progeny in a Japanese dwelling will be characterised by the different air conditions.

  14. Thermal modeling of a combined system of photovoltaic thermal (PV/T) solar water heater

    Energy Technology Data Exchange (ETDEWEB)

    Dubey, Swapnil; Tiwari, G.N. [Centre for Energy Studies, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016 (India)

    2008-07-15

    In this paper, an integrated combined system of a photovoltaic (glass-glass) thermal (PV/T) solar water heater of capacity 200 l has been designed and tested in outdoor condition for composite climate of New Delhi. An analytical expression for characteristic equation for photovoltaic thermal (PV/T) flat plate collector has been derived for different condition as a function of design and climatic parameters. The testing of collector and system were carried out during February-April, 2007. It is observed that the photovoltaic thermal (PV/T) flat plate collector partially covered with PV module gives better thermal and average cell efficiency which is in accordance with the results reported by earlier researchers. (author)

  15. Epinephrine plus argon plasma or heater probe coagulation in ulcer bleeding

    Institute of Scientific and Technical Information of China (English)

    Ahmet Karaman; Mevlut Baskol; Sebnem Gursoy; Edip Torun; Alper Yurci; Banu Demet Ozel; Kadri Guven; Omer Ozbakir; Mehmet Yucesoy

    2011-01-01

    AIM: To compare the effectiveness of argon plasma coagulation (APC) and heater probe coagulation (HPC) in non-variceal upper gastrointestinal bleeding. METHODS: Eighty-five (18 female, 67 male) patients admitted for acute gastrointestinal bleeding due to gastric or duodenal ulcer were included in the study. Upper endoscopy was performed and HPC or APC were chosen randomly to stop the bleeding. Initial hemostasis and rebleeding rates were primary and secondary end-points of the study. RESULTS: Initial hemostasis was achieved in 97.7% (42/43) and 81% (36/42) of the APC and HPC groups, respectively (P 0.05). CONCLUSION: APC is an effective hemostatic method in bleeding peptic ulcers. Larger multicenter trials are necessary to confirm these results.

  16. Extended and quasi-continuous tuning of quantum cascade lasers using superstructure gratings and integrated heaters

    Energy Technology Data Exchange (ETDEWEB)

    Bidaux, Yves, E-mail: yves.bidaux@alpeslasers.ch [Alpes Lasers SA, 1-3 Passsage Max Meuron, CH-2001 Neuchâtel (Switzerland); Institute for Quantum Electronics, ETH-Zurich, CH-8093 Zurich (Switzerland); Bismuto, Alfredo, E-mail: alfredo.bismuto@alpeslasers.ch; Tardy, Camille; Terazzi, Romain; Gresch, Tobias; Blaser, Stéphane; Muller, Antoine [Alpes Lasers SA, 1-3 Passsage Max Meuron, CH-2001 Neuchâtel (Switzerland); Faist, Jerome [Institute for Quantum Electronics, ETH-Zurich, CH-8093 Zurich (Switzerland)

    2015-11-30

    In this work, we demonstrate broad electrical tuning of quantum cascade lasers at 9.25 μm, 8.5 μm, and 4.4 μm in continuous wave operation using Vernier-effect distributed Bragg reflectors based on superstructure gratings. Integrated micro-heaters allow to switch from one Vernier channel to the other, while predictable and mode-hop free tuning can be obtained in each channel modulating the laser current with a side mode suppression ratio as high as 30 dB. The resulting device behaves effectively as a switchable multicolour tunable source. Tuning up to 6.5% of the central wavelength is observed. To prove the importance of the developed devices for high resolution molecular spectroscopy, a N{sub 2}O absorption spectrum has been measured.

  17. Low temperature ceiling heater of element construction. Niedertemperatur-Deckenheizung in Elementbauweise

    Energy Technology Data Exchange (ETDEWEB)

    Treinies, N.

    1980-03-13

    The purpose of the invention is to create a ceiling heater, which can manage with as low a temperature of the heat medium as possible, so that it will match the use of solar collectors and heat pumps, where the emission of heat upwards is to be kept as small as possible, and where a smooth underside of the ceiling without gaps is to be achieved. According to the invention, this problem is solved by the individual elements consists of a lower flat through metal plate, a hard foam core and a top through cover sheet forming a sandwich, and that the hard foam core has cut-outs corresponding to the shape of the heating duct on the side towards the lower metal plate. (HWJ).

  18. Dynamics of the triple contact line on a nonisothermal heater at partial wetting

    Science.gov (United States)

    Nikolayev, Vadim S.

    2010-08-01

    The dynamics of the triple gas-liquid-solid contact line is analyzed for the case where the gas is the saturated vapor corresponding to the liquid. For partial wetting conditions, a nonstationary contact line problem where the contact line motion is caused by evaporation or condensation is treated. It is shown that the Navier slip condition alone is not sufficient to relax the hydrodynamic contact line singularity: the Marangoni term is equally important when the heat transfer is involved. The transient heat conduction inside the heater is accounted for. A multiscale problem of drop evaporation with freely moving contact line is solved in the lubrication approximation as an illustration of the proposed approach.

  19. Analysis of Ruptured Heater Tube of Degasser Condenser in Wolsong Unit 4

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hong Pyo; Kim, J. S.; Lim, Y. S.; Kim, S. S.; Hwang, S. S.; Kim, D. J.; Kim, S. W.; Jeong, M. K.; Hong, J. H

    2007-08-15

    In a degasser condenser in Wolsong unit 4, the cracks were found in the heater tube no. 6 and no. 7. To avoid additional damages in the specimen during a decontamination process for the previous analysis, the cracks were analyzed without any decontamination process in this work. We performed the investigation of the ruptured surface morphology, the EDS analysis of the ruptured surface, the microstructural analysis of Alloy 800H sheath tube and literature survey to find the failure mechanism. From the results, it was expected that the sheath tube has been exposed in a steam condition as the coolant level was decreased in the degasser condenser, leading to the rupture of the sheath tube.

  20. Boiling Heat Transfer in High Temperature Generator of Absorption Chiller/Heater

    Science.gov (United States)

    Furukawa, Masahiro; Enomoto, Eiichi; Sekoguchi, Kotohiko

    The heat transfer performance of forced convective boiling was tested using a high temperature generator of absorption chiller/heater, the rear furnace wall of which was composed of two different surfaces; i. e., plain and sprayed heated surfaces. These two surfaces were bisymmetrically set. Wall surface temperatures of both the fire and fluid sides were measured at three locations along the upward flow direction in each heated surface for determining the heat flux and heat transfer coefficient. Nickel-chromium and alumina were employed as the spray materials. The test results show that the sprayed surface can yield a marked elevation in the heat transfer performance due to boiling on the plain surface. Therefore the level of heated surface temperature is largely reduced by means of the spraying surface treatment. This implies that the spraying would much improve a corrosive condition of the heated surface.

  1. Two-phase Flow Patterns in High Temperature Generator of Absorption Chiller / Heater

    Science.gov (United States)

    Furukawa, Masahiro; Kanuma, Hitoshi; Sekoguchi, Kotohiko; Takeishi, Masayuki

    There is a lack of information about vapor-liquid two-phase flow patterns determined using void signals in high temperature generator of absorption chiller/heater. Sensing void fraction has been hampered because lithium bromide aqueous solution of strong alkalinity is employed as working fluid at high temperature and high level of vacuum. New void sensor applicable to such difficult conditions was developed. The void Fractions at 48 locations in a high temperature generator were measured simultaneously in both cooling and heating operations. Analysis of void signals detected reveals that the most violent boiling occurs at the upper part of rear plate of combustion chamber and the first line of vertical tubes located in the flue. The flow patterns are strongly affected by the system pressure difference between the cooling and heating operations: there appear bubbly, slug and froth flows in the cooling operation, but only bubbly flow in the heating operation.

  2. Temperature buffer test. Installation of buffer, heaters and instruments in the deposition hole

    Energy Technology Data Exchange (ETDEWEB)

    Johannesson, Lars-Erik; Sanden, Torbjoern; Aakesson, Mattias [Clay Technology AB, Lund (Sweden); Barcena, Ignacio; Garcia-Sineriz, Jose Luis [Aitemin, Madrid (Spain)

    2010-12-15

    During 2003 the Temperature Buffer Test was installed in Aespoe Hard Rock Laboratory. Temperature, water pressure, relative humidity, total pressure and displacements etc. are measured in numerous points in the test. Most of the cables from the transducers are led in the deposition hole through slots in the rock surface of the deposition hole in watertight tubes to the data collection system in a container placed in the tunnel close to the deposition hole. This report describes the work with the installations of the buffer, heaters, and instruments and yields a description of the final location of all instruments. The report also contains a description of the materials that were installed and the densities yielded after placement.

  3. Closed and quasi-closed yoke configurations for travelling wave induction heaters

    Directory of Open Access Journals (Sweden)

    Ali K. Al-shaikhli

    2015-12-01

    Full Text Available The salient features of the travelling wave induction heating (TWIH make them very important technique in the field of heating flat metals. This study proposed two novel configurations, closed and quasi-closed, of the heater yoke. The proposed yokes designed to reduce the problems of slot effects and reduce the leakage flux, in order to focus the magnetic field within the heating region, which lead to improve the performance of the TWIH system. A finite-element simulation and analysis is represented in this study by using ANSYS^® programme code. A comparison analysis between the proposed configurations and the traditional one shows a superior performance of the proposed types for workpiece thickness >2 mm. The proposed methods give progress in produced power, efficiency and temperature about; 7–23, 15–40 and 10–25%, respectively, for thickness >2 mm. Moreover, wider and uniformed heat distributions are achieved with conjunction of typical yoke.

  4. Safety analysis for the Galileo light-weight radioisotope heater unit

    Science.gov (United States)

    Johnson, Ernest W.

    The Light-Weight Radioisotope Heater Unit (LWRHU) will be used on the NASA Galileo Mission to provide thermal energy to the various systems on the orbiter and probe that are adversely affected by the low temperature a spacecraft encounters during a long interplanetary mission. Using these plutonia-fueled sources in 1-W increments permits employment of a single design and provides the spacecraft user the option of how many to use and where to position them to satisfy the proper thermal environment for components requiring such consideration. The use of the radioisotope Pu 238 in these devices necessitates the assessment of postulated radiological risks which might be experienced in case of accidents or malfunctions of the space shuttle or the spacecraft during phases of the mission in the vicinity of the earth. Included are data for the design, mission descriptions, postulated accidents with their consequences, test data, and the derived source terms and personnel exposures for the various events.

  5. Performance of polypropylene and steel tubes in solar water heaters with natural circulation

    Energy Technology Data Exchange (ETDEWEB)

    Riazi, M.R. [Kuwait Univ., Safat (Kuwait). Chemical Engineering Dept.; Razavi, J. [Sharif Univ. of Technology, Tehran (Iran, Islamic Republic of). Chemical Engineering Dept.

    1997-02-01

    Performance of solar water heaters in thermosyphonic flow with polypropylene and steel tubes was studied experimentally. An experimental apparatus consisting of 36 south-facing parallel tubes was designed and built especially for this study. Experiments were performed at Sharif University of Technology in Tehran during July--August 1994 from 0900 to 1700, when the ambient temperature varied from 29 to 36 C. Overall, 30 experiments were conducted for both types of tubes. At first, it was found that the best collector slope for both types of tubes was 36{degree} and it is independent of tube type. Generally, it was found that polypropylene tubes under similar conditions can increase water temperature by 10 C more than steel tubes. Based on the results shown in this study, use of polypropylene tubes in solar water heating systems is recommended.

  6. Theoretical and experimental study of solar water heater with internal exchanger using thermosiphon system

    Energy Technology Data Exchange (ETDEWEB)

    Koffi, P.M.E.; Andoh, H.Y.; Gbaha, P. [Laboratoire d' Energies Nouvelles et Renouvelables, Institut National Polytechnique Felix Houphoeuet-Boigny, B.P. 1526 Yamoussoukro (Ivory Coast); Toure, S. [Laboratoire d' Energie Solaire, Universite de Cocody, 22 B.P. 582, Abidjan 22 (Ivory Coast); Ado, G. [Laboratoire des Procedes, Industriels de Syntheses de l' Environnement et de l' Energie Nouvelle, INP-HB 22, B.P. 1093 Yamoussoukro (Ivory Coast)

    2008-08-15

    This study presents a theoretical and experimental analysis of the thermal performance of a solar water heater prototype with an internal exchanger using a thermosiphon system. The heat exchanger made of a rolled copper tube is placed diagonally in the storage tank so that the hot fluid crosses a significant mass of stored water. The results focus mainly on the levels of the heat fluxes, temperatures recorded, mass flow rate and efficiency of the collector. During the main insulation period, one obtains satisfactory qualitative and quantitative agreement between the experimental and theoretical results of mass flow rate and temperatures. Those indicate heat fluxes whose peak reaches 989 W/m{sup 2}, collector outlet water temperature levels of more than 85.5 C and a collector thermal effectiveness around 58%. (author)

  7. Solar water heaters. A review of systems research and design innovation

    Energy Technology Data Exchange (ETDEWEB)

    Norton, Brian [Dublin Institute of Technology (Ireland). Dublin Energy Lab.

    2011-07-01

    Solar water heating can be considered to be an established mature technology. The achievement of this status is the outcome of over a century of system development that culminated with a flourish of innovation in the last thirty years. Drivers for research and development have been achieving economic viability by devising systems that, for specific applications in particular climate contexts produced more hot water per unit cost. Reductions in both initial capital and installation costs have been achieved as well as in those associated with subsequent operation and maintenance. Research on solar water heating is discussed with the emphasis on overall systems though some key aspects of component development are also outlined. A comprehensive taxonomy is presented of the generic types of solar water heater that have emerged and their features, characteristics and performance are discussed. (orig.)

  8. Alkali metal compatibility testing of candidate heater head materials for a Stirling engine heat transport system

    Science.gov (United States)

    Noble, Jack E.; Hickman, Gary L.; Grobstein, Toni

    The authors describe work performed as part of the 25-kWe advanced Stirling conversion system project. Liquid alkali metal compatibility is being assessed in an ongoing test program to evaluate candidate heater head materials and fabrication processes at the temperatures and operating conditions required for Stirling engines. Specific materials under evaluation are alloy 713LC, alloy 713LC coated with nickel aluminide, and Udimet 720, each in combination with Waspaloy. The tests were run at a constant 700 C. A eutectic alloy of sodium and potassium (NaK) was the working fluid. Titanium sheet in the system was shown to be an effective oxygen getter. Metallographic and microchemical examination of material surfaces, joints, and their interfaces revealed little or no corrosion after 1000 h. Tests are in progress, with up to 10,000 h exposure.

  9. Residence time distribution (RTD) of particulate foods in a continuous flow pilot-scale ohmic heater.

    Science.gov (United States)

    Sarang, Sanjay; Heskitt, Brian; Tulsiyan, Priyank; Sastry, Sudhir K

    2009-08-01

    The residence time distribution (RTD) of a model particulate-fluid mixture (potato in starch solution) in the ohmic heater in a continuous sterilization process was measured using a radio frequency identification (RFID) methodology. The effect of solid concentration and the rotational speed of the agitators on the RTD were studied. The velocity of the fastest particle was 1.62 times the mean product velocity. In general, particle velocity was found to be greater than the product bulk average velocity. Mean particle residence time (MPRT) increased with an increase in the rotational speed of the agitators (P < 0.05), and no particular trend was observed between the MPRT and the solid concentration. The distribution curves E (theta) were skewed to the right suggesting slow moving zones in the system.

  10. Using the column wall itself as resistive heater for fast temperature gradients in liquid chromatography.

    Science.gov (United States)

    De Pauw, Ruben; Pursch, Matthias; Desmet, Gert

    2015-11-13

    A new system is proposed for applying fast temperature gradients in liquid chromatography. It consists of a 0.7 mm × 150 mm fused-silica column coated with a 50 μm Nickel-layer, which is connecting with a power source and a temperature control system to perform fast and reproducible temperature gradients using the column wall itself as a resistive heater. Applying a current of 4A and passive cooling results in a maximal heating and cooling rate of, respectively, 71 and -21 °C/min. Multi-segment temperature gradients were superimposed on mobile phase gradients to enhance the selectivity for three sets of mixtures (pharmaceutical compounds, a highly complex mixture and an insecticide sample). This resulted in a higher peak count or better selectivities for the various mixtures.

  11. EGFR-targeted magnetic nanoparticle heaters kill cancer cells without a perceptible temperature rise.

    Science.gov (United States)

    Creixell, Mar; Bohórquez, Ana C; Torres-Lugo, Madeline; Rinaldi, Carlos

    2011-09-27

    It is currently believed that magnetic nanoparticle heaters (MNHs) can kill cancer cells only when the temperature is raised above 43 °C due to energy dissipation in an alternating magnetic field. On the other hand, simple heat conduction arguments indicate that in small tumors or single cells the relative rates of energy dissipation and heat conduction result in a negligible temperature rise, thus limiting the potential of MNHs in treating small tumors and metastatic cancer. Here we demonstrate that internalized MNHs conjugated to epidermal growth factor (EGF) and which target the epidermal growth factor receptor (EGFR) do result in a significant (up to 99.9%) reduction in cell viability and clonogenic survival in a thermal heat dose dependent manner, without the need for a perceptible temperature rise. The effect appears to be cell type specific and indicates that magnetic nanoparticles in alternating magnetic fields may effectively kill cancer cells under conditions previously considered as not possible.

  12. An efficient plate heater with uniform surface temperature engineered with effective thermal materials

    CERN Document Server

    Liu, Yichao; He, Sailing; Ma, Yungui

    2014-01-01

    Extended from its electromagnetic counterpart, transformation thermodynamics applied to thermal conduction equations can map a virtual geometry into a physical thermal medium, realizing the manipulation of heat flux with almost arbitrarily desired diffusion paths, which provides unprecedented opportunities to create thermal devices unconceivable or deemed impossible before. In this work we employ this technique to design an efficient plate heater that can transiently achieve a large surface of uniform temperature powered by a small thermal source. As opposed to the traditional approach of relying on the deployment of a resistor network, our approach fully takes advantage of an advanced functional material system to guide the heat flux to achieve the desired temperature heating profile. A different set of material parameters for the transformed device has been developed, offering the parametric freedom for practical applications. As a proof of concept, the proposed devices are implemented with engineered therm...

  13. Modeling the performance limits of novel microcantilever heaters for volatile organic compound detection

    Science.gov (United States)

    Jahangir, Ifat; Koley, Goutam

    2017-01-01

    We present a theoretical model estimating the performance limits of novel AlGaN/GaN heterostructure based microcantilever heater sensors to perform advanced volatile organic compound (VOC) detection and mixture analysis. Operating without any specific surface functionalization or treatment; these devices utilize the strong surface polarization of AlGaN as well as the unique device geometries, to perform selective detection of analytes based on their latent heat of evaporation and molecular dipole moment over a wide concentration range. The presented model incorporates heat transfer, Joule heating, thermal expansion and evaporative heat loss mechanisms, to predict device behaviors such as temperature profiles and sensing performance limits under various steady-state and transient test conditions. In addition, the versatility of the proposed model enables us to successfully predict the capability of the device to perform mixture analysis, and provides guidelines to further optimize the device properties to achieve a limit of detection in sub-ppm concentration.

  14. Using Thin-Film Thermometers as Heaters in Thermal Control Applications

    Science.gov (United States)

    Cho, Hyung J.; Penanen, Konstantin; Sukhatme, Kalyani G.; Holmes, Warren A.; Courts, Scott

    2010-01-01

    A cryogenic sensor maintains calibration at approximately equal to 4.2 K to better than 2 mK (< 0.5 percent resistance repeatability) after being heated to approximately equal 40 K with approximately equal 0.5 W power. The sensor withstands 4 W power dissipation when immersed in liquid nitrogen with verified resistance reproducibility of, at worst, 1 percent. The sensor maintains calibration to 0.1 percent after being heated with 1-W power at approximately equal 77 K for a period of 48 hours. When operated with a readout scheme that is capable of mitigating the self-heating calibration errors, this and similar sensors can be used for precision (mK stability) temperature control without the need of separate heaters and associated wiring/cabling.

  15. Relationship between Organic Carbon and Opportunistic Pathogens in Simulated Glass Water Heaters

    Directory of Open Access Journals (Sweden)

    Krista Williams

    2015-06-01

    Full Text Available Controlling organic carbon levels in municipal water has been hypothesized to limit downstream growth of bacteria and opportunistic pathogens in premise plumbing (OPPPs. Here, the relationships between influent organic carbon (0–15,000 µg ozonated fulvic acid /L and the number of total bacteria [16S rRNA genes and heterotrophic plate counts (HPCs] and a wide range of OPPPs (gene copy numbers of Acanthamoeba polyphaga, Vermamoeba vermiformis, Legionella pneumophila, and Mycobacterium avium were examined in the bulk water of 120-mL simulated glass water heaters (SGWHs. The SGWHs were operated at 32–37 °C, which is representative of conditions encountered at the bottom of electric water heaters, with water changes of 80% three times per week to simulate low use. This design presented advantages of controlled and replicated (triplicate conditions and avoided other potential limitations to OPPP growth in order to isolate the variable of organic carbon. Over seventeen months, strong correlations were observed between total organic carbon (TOC and both 16S rRNA gene copy numbers and HPC counts (avg. R2 > 0.89. Although M. avium gene copies were occasionally correlated with TOC (avg. R2 = 0.82 to 0.97, for 2 out of 4 time points and over a limited TOC range (0–1000 µg/L, no other correlations were identified between other OPPPs and added TOC. These results suggest that reducing organic carbon in distributed water is not adequate as a sole strategy for controlling OPPPs, although it may have promise in conjunction with other approaches.

  16. In-situ tuff water migration/heater experiment: experimental plan

    Energy Technology Data Exchange (ETDEWEB)

    Johnstone, J.K.

    1980-08-01

    Tuffs on the Nevada Test Site (NTS) are currently under investigation as a potential isolation medium for heat-producing nuclear wastes. The National Academy of Sciences has concurred in our identification of the potentially large water content ({le}40 vol %) of tuffs as one of the important issues affecting their suitability for a repository. This Experimental Plan describes an in-situ experiment intended as an initial assessment of water generation/migration in response to a thermal input. The experiment will be conducted in the Grouse Canyon Welded Tuff in Tunnel U12g (G-Tunnel) located in the north-central region of the NTS. While the Grouse Canyon Welded Tuff is not a potential repository medium, it has physical, thermal, and mechanical properties very similar to those tuffs currently under consideration and is accessible at depth (400 m below the surface) in an existing facility. Other goals of the experiment are to support computer-code and instrumentation development, and to measure in-situ thermal properties. The experimental array consists of a central electrical heater, 1.2 m long x 10.2 cm diameter, surrounded by three holes for measuring water-migration behavior, two holes for measuring temperature profiles, one hole for measuring thermally induced stress in the rock, and one hole perpendicular to the heater to measure displacement with a laser. This Experimental Plan describes the experimental objectives, the technical issues, the site, the experimental array, thermal and thermomechanical modeling results, the instrumentation, the data-acquisition system, posttest characterization, and the organizational details.

  17. Relationship between material properties and transparent heater performance for both bulk-like and percolative nanostructured networks.

    Science.gov (United States)

    Sorel, Sophie; Bellet, Daniel; Coleman, Jonathan N

    2014-05-27

    Transparent heaters are important for many applications and in the future are likely to be fabricated from thin, conducting, nanostructured networks. However, the electrical properties of such networks are almost always controlled by percolative effects. The impact of percolation on heating effects has not been considered, and the material parameter combinations that lead to efficient performance are not known. In fact, figures of merit for transparent heaters have not been elucidated, either in bulk-like or percolative systems. Here, we develop a simple yet comprehensive model describing the operation of transparent heaters. By considering the balance of Joule heating versus power dissipated by both convection and radiation, we derive an expression for the time-dependent heater temperature as a function of both electrical and thermal parameters. This equation can be modified to describe the relationship between temperature, optical transmittance, and electrical/thermal parameters in both bulk-like and percolative systems. By performing experiments on silver nanowire networks, systems known to display both bulk-like and percolative regimes, we show the model to describe real systems extremely well. This work shows the performance of transparent heaters in the percolative regime to be significantly less efficient compared to the bulk-like regime, implying the diameter of the nanowires making up the network to be critical. The model allows the identification of figures of merit for networks in both bulk-like and percolative regimes. We show that metallic nanowire networks are most promising, closely followed by CVD graphene, with networks of solution-processed graphene and carbon nanotubes being much less efficient.

  18. Regional Climate Zone Modeling of a Commercial Absorption Heat Pump Hot Water Heater Part 1: Southern and South Central Climate Zones

    Energy Technology Data Exchange (ETDEWEB)

    Geoghegan, Patrick J [ORNL; Shen, Bo [ORNL; Keinath, Christopher M. [Stone Mountain Technologies, Inc., Johnson City; Garrabrant, Michael A. [Stone Mountain Technologies, Inc., Johnson City

    2016-01-01

    Commercial hot water heating accounts for approximately 0.78 Quads of primary energy use with 0.44 Quads of this amount from natural gas fired heaters. An ammonia-water based commercial absorption system, if fully deployed, could achieve a high level of savings, much higher than would be possible by conversion to the high efficiency nonheat-pump gas fired alternatives. In comparison with air source electric heat pumps, the absorption system is able to maintain higher coefficients of performance in colder climates. The ammonia-water system also has the advantage of zero Ozone Depletion Potential and low Global Warming Potential. A thermodynamic model of a single effect ammonia-water absorption system for commercial space and water heating was developed, and its performance was investigated for a range of ambient and return water temperatures. This allowed for the development of a performance map which was then used in a building energy modeling software. Modeling of two commercial water heating systems was performed; one using an absorption heat pump and another using a condensing gas storage system. The energy and financial savings were investigated for a range of locations and climate zones in the southern and south central United States. A follow up paper will analyze northern and north/central regions. Results showed that the system using an absorption heat pump offers significant savings.

  19. Investigation of cored bricks matrix preliminary design and thermal analysis for high temperature wind tunnel storage heater%高温风洞蓄热式加热器蓄热单元初步设计与分析

    Institute of Scientific and Technical Information of China (English)

    罗飞腾; 宋文艳; 刘伟雄; 李建平

    2013-01-01

    The storage heater is the one of heating methods for current high temperature clean air wind-tunnel application. Aiming at cored bricks storage heater, the preliminary design procedure of cored bricks matrix was investigated, including thermal performance analysis, pressure-drop and thermal stress evaluation. Combined with a typical wind-tunnel test condition, a cored bricks matrix was preliminarily designed and analyzed in detail. Especially the effects of geometric parameters on thermal performance, pressure-drop and thermal stress resistance were evaluated. The evaluation results indicate that the hole diameter and spacing are the most important design parameters dominating the other geometric parameters, heater working performance and security. The matrix height is a key designed parameter to stabilize the outlet air temperature and test duration. The preliminary design concept of cored bricks matrix was finally selected in consideration of tradeoff, which suggested that the expected Mach 6. 0 flight conditions can be well simulated by the designed cored bricks matrix of storage heater. The present research efforts could provide well reference for conceptual design and scheme evaluation of the cored bricks storage heater.%蓄热式加热器是目前高温纯净空气风洞最具潜力和优势的一种加热方式.针对空心砖型蓄热式加热器,开展了空心砖型蓄热单元初步设计研究,涉及换热性能、压降控制和热应力评估等方面.结合一个预定的试验状态要求,对空心砖型蓄热单元的初步设计进行分析与讨论,评估孔径、孔间距、蓄热阵高度等几何设计参数对换热性能、压降控制和当地热应力水平的影响,进而确定空心砖型蓄热单元的基本设计方案,结果表明孔径、孔间距是加热器设计的关键参数,对其它参数、运行性能、安全性具有显著影响,高度选择直接影响出口气流温度水平及其稳定时间,初

  20. Dimensioning of a solar water heater made from PET bottles; Dimensionamento de um aquecedor solar de agua feito com garrafas PET

    Energy Technology Data Exchange (ETDEWEB)

    Bertoleti, Pedro Henrique Fonseca; Souza, Teofilo Miguel de [Universidade Estadual Paulista (UNESP), Guaratingueta, SP (Brazil). Centro de Energias Renovaveis

    2008-07-01

    This document show the solar water heater made of PET bottles, a simple-construction solar water heater that try to give us two important solutions, water heating using solar energy and reutilization of the PET bottles left in the nature. Also, it will be showed how to do the dimensioning of it. Based on the showed dimensioning a application / software is developed and after that simulations are made using the application to provide how is the economy if it's used this kind of solar water heater and their environmental contribution by reutilization of the PET bottles abandoned in the nature. For example, in a common home the economy is about 45% of the electricity bill considering that the warmed water is used just to take a shower. So, the conclusion is: the solar water heater made by PET bottles is a very relevant equipment to the use of the solar energy, to useful applications and environmental contribution. (author)

  1. Avaliação do desempenho de um aquecedor para aves adaptado para utilizar biogás como combustível Birds heater adaptation and performance using biogas as fuel

    Directory of Open Access Journals (Sweden)

    Tânia M. B. Santos

    2007-12-01

    pressures in the heater entrance of 10, 12, 15, 17 and 20 cm of water column. Results showed that expressions for theoretical calculation and proposed parameters in the literature can be used for aviaries heaters adaptation. The adaptation is simple, indicating the viability for utilization of existing heaters in farms and in the market. Air temperatures were similar to the obtained with the original fuel (LPG.

  2. Influence of yttrium iron garnet thickness and heater opacity on the nonlocal transport of electrically and thermally excited magnons

    Science.gov (United States)

    Shan, Juan; Cornelissen, Ludo J.; Vlietstra, Nynke; Ben Youssef, Jamal; Kuschel, Timo; Duine, Rembert A.; van Wees, Bart J.

    2016-11-01

    We studied the nonlocal transport behavior of both electrically and thermally excited magnons in yttrium iron garnet (YIG) as a function of its thickness. For electrically injected magnons, the nonlocal signals decrease monotonically as the YIG thickness increases. For the nonlocal behavior of the thermally generated magnons, or the nonlocal spin Seebeck effect (SSE), we observed a sign reversal which occurs at a certain heater-detector distance, and it is influenced by both the opacity of the YIG/heater interface and the YIG thickness. Our nonlocal SSE results can be qualitatively explained by the bulk-driven SSE mechanism together with the magnon diffusion model. Using a two-dimensional finite element model (2D-FEM), we estimated the bulk spin Seebeck coefficient of YIG at room temperature. The quantitative disagreement between the experimental and modeled results indicates more complex processes going on in addition to magnon diffusion and relaxation, especially close to the contacts.

  3. Thermal chip fabrication with arrays of sensors and heaters for micro-scale impingement cooling heat transfer analysis and measurements.

    Science.gov (United States)

    Shen, C H; Gau, C

    2004-07-30

    The design and fabrication for a thermal chip with an array of temperature sensors and heaters for study of micro-jet impingement cooling heat transfer process are presented. This thermal chip can minimize the heat loss from the system to the ambient and provide a uniform heat flux along the wall, thus local heat transfer processes along the wall can be measured and obtained. The fabrication procedure presented can reach a chip yield of 100%, and every one of the sensors and heaters on the chip is in good condition. In addition, micro-jet impingement cooling experiments are performed to obtain the micro-scale local heat transfer Nusselt number along the wall. Flow visualization for the micro-impinging jet is also made. The experimental results indicate that both the micro-scale impinging jet flow structure and the heat transfer process along the wall is significantly different from the case of large-scale jet impingement cooling process.

  4. Natural convective heat transfer and nanofluid flow in a cavity with top wavy wall and corner heater

    Institute of Scientific and Technical Information of China (English)

    Mikhail A SHEREMET; Ioan POP; Hakan F ZTOP; Nidal ABU-HAMDEH

    2016-01-01

    A numerical analysis of natural convection of nanofluid in a wavy-walled enclosure with an isothermal corner heater has been carried out. The cavity is heated from the left bottom corner and cooled from the top wavy wall while the rest walls are adiaba- tic. Mathematical model has been formulated using the single-phase nanofluid approach. Main efforts have been focused on the effects of the dimensionless time, Rayleigh number, undulation number, nanoparticle volume fraction and length of corner heaters on the fluid flow and heat transfer inside the cavity. Numerical results have been presented in the form of streamlines, isotherms, velocity and temperature profiles, local and average Nusselt numbers. It has been found that nanoparticle volume fraction essentially affects both fluid flow and heat transfer while undulation number changes significantly only the heat transfer rate.

  5. Heater Choice, Dampness and Mould Growth in 26 New Zealand Homes: A Study of Propensity for Mould Growth Using Encapsulated Fungal Spores

    OpenAIRE

    2015-01-01

    The relationship between the use of unflued gas heaters (UGH, N = 14) and heat pump heaters (HP, N = 12) located in the living rooms, and mould growth on the living room and bedroom walls, of 26 New Zealand (NZ) occupied homes was investigated during winter. Two methods were employed to evaluate the potential of mould growth on walls: (i) measurement of daily hyphal growth rate using a fungal detector (encapsulated fungal spores); and (ii) estimation of fungal contamination based on a four l...

  6. Study of thermal effects and optical properties of an innovative absorber in integrated collector storage solar water heater

    Science.gov (United States)

    Taheri, Yaser; Alimardani, Kazem; Ziapour, Behrooz M.

    2015-10-01

    Solar passive water heaters are potential candidates for enhanced heat transfer. Solar water heaters with an integrated water tank and with the low temperature energy resource are used as the simplest and cheapest recipient devices of the solar energy for heating and supplying hot water in the buildings. The solar thermal performances of one primitive absorber were determined by using both the experimental and the simulation model of it. All materials applied for absorber such as the cover glass, the black colored sands and the V shaped galvanized plate were submerged into the water. The water storage tank was manufactured from galvanized sheet of 0.0015 m in thickness and the effective area of the collector was 0.67 m2. The absorber was installed on a compact solar water heater. The constructed flat-plate collectors were tested outdoors. However the simulation results showed that the absorbers operated near to the gray materials and all experimental results showed that the thermal efficiencies of the collector are over than 70 %.

  7. Comparative Experimental Analysis of the Thermal Performance of Evacuated Tube Solar Water Heater Systems With and Without a Mini-Compound Parabolic Concentrating (CPC Reflector(C < 1

    Directory of Open Access Journals (Sweden)

    Yuehong Su

    2012-04-01

    Full Text Available Evacuated tube solar water heater systems are widely used in China due to their high thermal efficiency, simple construction requirements, and low manufacturing costs. CPC evacuated tube solar water heaters with a geometrical concentration ratio C of less than one are rare. A comparison of the experimental rig of evacuated tube solar water heater systems with and without a mini-CPC reflector was set up, with a series of experiments done in Hefei (31°53'N, 117°15'E, China. The first and second laws of thermodynamics were used to analyze and contrast their thermal performance. The water in the tank was heated from 26.9 to 55, 65, 75, 85, and 95 °C. Two types of solar water heater systems were used, and the data gathered for two days were compared. The results show that when attaining low temperature water, the evacuated tube solar water heater system without a mini-CPC reflector has higher thermal and exergy efficiencies than the system with a mini-CPC reflector, including the average and immediate values. On the other hand, when attaining high temperature water, the system with a mini-CPC reflector has higher thermal and exergy efficiencies than the other one. The comparison presents the advantages of evacuated tube solar water heater systems with and without a mini-CPC reflector, which can be offered as a reference when choosing which solar water system to use for actual applications.

  8. Space Heaters, Computers, Cell Phone Chargers: How Plugged In AreCommercial Buildings?

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, Marla; Webber, Carrie; Brown, Richard; Busch, John; Pinckard, Margaret; Roberson, Judy

    2007-02-28

    Evidenceof electric plug loads in commercial buildings isvisible everyday: space heaters, portable fans, and the IT technician'stwo monitors connected to one PC. The Energy Information Administrationestimates that office and miscellaneous equipment together will consume2.18 quads in 2006, nearly 50 percent of U.S. commercial electricity use.Although the importance of commercial plug loads is documented, its verynature (diverse product types, products not installed when buildinginitially constructed, and products often hidden in closets) makes itdifficult to accurately count and categorize the end use.We auditedsixteen buildings in three cities (San Francisco, Atlanta, Pittsburgh)including office, medical and education building types. We inventoriedthe number and types of office and miscellaneous electric equipment aswell as estimated total energy consumption due to these product types. Intotal, we audited approximately 4,000 units of office equipment and 6,000units of miscellaneous equipment and covered a diverse range of productsranging from electric pencil sharpeners with a unit energy consumption(UEC) of 1 kWh/yr to a kiln with a UEC of 7,000 kWh/yr. Our paperpresents a summary of the density and type of plug load equipment foundas well as the estimated total energy consumption of the equipment.Additionally, we present equipment trends observed and provide insightsto how policy makers can target energy efficiency for this growing enduse.

  9. Numerical Investigation of Urea Freezing and Melting Characteristics Using Coolant Heater

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Yeop; Kim, Nam Il; Kim, Man Young [Chounbuk Nat' l Univ., Jeonju (Korea, Republic of); Park, Yun Beom [Jeju College of Technology, Jeju (Korea, Republic of)

    2013-08-15

    UREA-SCR technology is known as one of the powerful NOx reduction systems for vehicles as well as stationary applications. For its consistent and reliable operation in vehicle applications, however, the freezing and melting of the urea solution in cold environments have to be resolved. In this study, therefore, a numerical study of three-dimensional unsteady problems was analyzed to understand the urea freezing and heating phenomena and heat transfer characteristics in terms of urea liquid volume fraction, temperature profiles, and phase change behavior in urea solutions with time by using the commercial software Fluent 6.3. As a result, it was found that the freezing phenomenon proceeds with a phase change from the tank wall to the center, whereas the melting phenomenon occurs faster in the upper part of the storage tank by natural convection and in the adjacent part of the coolant pipe than in other parts. Furthermore, approximately 190s were required to obtain 1a of urea solution using a 4-coiled coolant heater under conditions of 70 .deg. C and 200 L/h.

  10. Self-construction of a solar water heater; Calentador solar de agua de auto-construccion

    Energy Technology Data Exchange (ETDEWEB)

    Lentz Herrera, Alvaro E.; Rincon Mejia, Eduardo A. [Universidad Autonoma de la Ciudad de Mexico, Mexico, D.F. (Mexico)

    2009-07-01

    In this work a flat receiver of self construction is shown with relatively low cost and easy manufacture, but with a thermal efficiency superior to 40% for applications at temperatures less than 60 degrees Celsius, that allows satisfying international standards in this respect. The heater has been matter of study in open courses distributed in the Universidad Autonoma de la Ciudad de Mexico (UACM) oriented to that the participants construct their own system, in addition to its installation and tests. The obtained results have been excellent. The massive use of efficient solar receivers of self-construction can truly help to the decreasing of the gas discharges of greenhouse effect. [Spanish] En este trabajo se presenta un captador plano de auto construccion con relativamente bajo costo y facil manufactura, pero con un rendimiento termico superior a 40% para aplicaciones a temperatura menos de 60 grados centigrados que le permite satisfacer estandares internacionales a este respecto. El calentador ha sido materia de estudio en cursos abiertos impartidos en la Universidad Autonoma de la Ciudad de Mexico (UACM) orientados a que los participantes construyan su propio sistema, ademas de su instalacion y pruebas. Los resultados obtenidos han sido excelentes. El uso masivo de captadores solares eficientes de autoconstruccion puede en verdad coadyuvar a la disminucion de las emisiones de gases de efecto invernadero.

  11. Coated particle fuel for radioisotope power systems (RPSs) and radioisotope heater units (RHUs)

    Science.gov (United States)

    Sholtis, Joseph A.; Lipinski, Ronald J.; El-Genk, Mohamed S.

    1999-01-01

    Coated particle fuel offers great promise for advanced radioisotope power systems (RPSs) and radioisotope heater units (RHUs) being pursued for future U.S. solar system exploration missions. Potential benefits of this fuel include improved design flexibility and materials compatibility, enhanced safety and performance, and reduced specific mass and volume. This paper describes and discusses coated particle fuel, with emphasis on its applicability, attributes, and potential benefits to future RPSs and RHUs. Additionally, this paper identifies further analyses and verification testing that should be conducted before a commitment is made to fully develop this fuel. Efforts to date indicate there is every reason to believe that the potential benefits of coated particle fuel to future RPSs and RHUs can be demonstrated with a modest, phased analytical and verification test effort. Thus, developmental risk appears minimal, while the potential benefits are substantial. If coated particle fuel is pursued and ultimately developed successfully, it could revolutionize the design and space use of future RPSs and RHUs.

  12. MHD natural convection in an inclined wavy cavity with corner heater filled with a nanofluid

    Science.gov (United States)

    Sheremet, M. A.; Oztop, H. F.; Pop, I.

    2016-10-01

    A mathematical modelling of MHD free convection in an inclined wavy enclosure filled with a Cu-water nanofluid in the presence of an isothermal corner heater has been carried out. The cavity is heated from the left bottom corner and cooled from the top wavy wall while the rest walls are adiabatic. Uniform magnetic field affects the heat transfer and fluid flow with an inclination angle to the axis xbar. Wavy cavity is inclined to the horizontal direction. Mathematical model formulated using the single-phase nanofluid approach in dimensionless variables stream function, vorticity and temperature has been solved by finite difference method of the second order accuracy in a wide range of governing parameters: Hartmann number (Ha=0-100), inclination angle of the magnetic field (χ = 0 - π) , undulation number (κ=0-4), inclination angle of the cavity (ζ = 0 - π) , solid volume fraction parameter of nanoparticles (φ=0.0-0.05), and dimensionless time (τ=0-0.27). Main efforts have been focused on the effects of these parameters on the fluid flow and heat transfer inside the cavity. Numerical results have been presented in the form of streamlines, isotherms and average Nusselt numbers.

  13. Heat Flux at the Surface of Metal Foil Heater under Evaporating Sessile Droplets

    Directory of Open Access Journals (Sweden)

    Igor Marchuk

    2015-01-01

    Full Text Available Evaporating water drops on a horizontal heated substrate were investigated experimentally. The heater was made of a constantan foil with the thickness of 25 μm and size of 42 × 35 mm2. The temperature of the bottom foil surface was measured by the infrared (IR camera. To determine the heat flux density during evaporation of liquid near the contact line, the Cauchy problem for the heat equation was solved using the temperature data. The maximum heat flux density is obtained in the contact line region and exceeds the average heat flux density from the entire foil surface by the factor of 5–7. The average heat flux density in the region wetted by the drop exceeds the average heat flux density from the entire foil surface by the factor of 3–5. This fact is explained by the heat influx from the foil periphery to the drop due to the relatively high heat conductivity coefficient of the foil material and high evaporation rate in the contact line region. Heat flux density profiles for pairs of sessile droplets are also investigated.

  14. Characterization of discontinuities in the Stripa granite. Time-scale heater experiment

    Energy Technology Data Exchange (ETDEWEB)

    Thorpe, R.

    1979-07-01

    The report describes the methodology and results of a detailed study of geologic discontinuities associated with the time-scale heater test at the Stripa mine in Sweden. Mapping of the floor of the experiment tunnel coupled with observation of core samples from beneath the drift indicate that four N-striking shear fractures dip steeply through the 6 x 10 x 25-m rock mass. Oblique-thrust faulting has produced displacements of up to 2 m on one of the surfaces, and its inferred 3-D configuration is consistent with observed slickensiding. Resolution of locally measured principal stresses on the shear plane yields a theoretical shear direction that also coincides with the slickensiding. Four distinct joint sets exist locally, one of which coincides with the shear fractures. Another lies nearly horizontal, and two others are steeply inclined. Fracture length and spacing distributions for the four joint sets are shown to be lognormal. Two of the sets lie perpendicular to principal stress directions. The fact that one of these two joint sets apparently post-dates other fracturing and is normal to the minimum principal stress suggests that it is due to isostatic rebound.

  15. Water solar distiller productivity enhancement using concentrating solar water heater and phase change material (PCM

    Directory of Open Access Journals (Sweden)

    Miqdam T. Chaichan

    2015-03-01

    Full Text Available This paper investigates usage of thermal energy storage extracted from concentrating solar heater for water distillation. Paraffin wax selected as a suitable phase change material, and it was used for storing thermal energy in two different insulated treasurers. The paraffin wax is receiving hot water from concentrating solar dish. This solar energy stored in PCM as latent heat energy. Solar energy stored in a day time with a large quantity, and some heat retrieved for later use. Water’s temperature measured in a definite interval of time. Four cases were studied: using water as storage material with and without solar tracker. Also, PCM was as thermal storage material with and without solar tracker.The system working time was increased to about 5 h with sun tracker by concentrating dish and adding PCM to the system. The system concentrating efficiency, heating efficiency, and system productivity, has increased by about 64.07%, 112.87%, and 307.54%, respectively. The system working time increased to 3 h when PCM added without sun tracker. Also, the system concentrating efficiency increased by about 50.47%, and the system heating efficiency increased by about 41.63%. Moreover, the system productivity increased by about 180%.

  16. Advanced Stirling Duplex Materials Assessment for Potential Venus Mission Heater Head Application

    Science.gov (United States)

    Ritzert, Frank; Nathal, Michael V.; Salem, Jonathan; Jacobson, Nathan; Nesbitt, James

    2011-01-01

    This report will address materials selection for components in a proposed Venus lander system. The lander would use active refrigeration to allow Space Science instrumentation to survive the extreme environment that exists on the surface of Venus. The refrigeration system would be powered by a Stirling engine-based system and is termed the Advanced Stirling Duplex (ASD) concept. Stirling engine power conversion in its simplest definition converts heat from radioactive decay into electricity. Detailed design decisions will require iterations between component geometries, materials selection, system output, and tolerable risk. This study reviews potential component requirements against known materials performance. A lower risk, evolutionary advance in heater head materials could be offered by nickel-base superalloy single crystals, with expected capability of approximately 1100C. However, the high temperature requirements of the Venus mission may force the selection of ceramics or refractory metals, which are more developmental in nature and may not have a well-developed database or a mature supporting technology base such as fabrication and joining methods.

  17. West Village Community: Quality Management Processes and Preliminary Heat Pump Water Heater Performance

    Energy Technology Data Exchange (ETDEWEB)

    Dakin, B.; Backman, C.; Hoeschele, M.; German, A.

    2012-11-01

    West Village, a multi-use project underway at the University of California Davis, represents a ground-breaking sustainable community incorporating energy efficiency measures and on-site renewable generation to achieve community-level Zero Net Energy (ZNE) goals. The project when complete will provide housing for students, faculty, and staff with a vision to minimize the community's impact on energy use by reducing building energy use, providing on-site generation, and encouraging alternative forms of transportation. This focus of this research is on the 192 student apartments that were completed in 2011 under Phase I of the West Village multi-year project. The numerous aggressive energy efficiency measures implemented result in estimated source energy savings of 37% over the B10 Benchmark. There are two primary objectives of this research. The first is to evaluate performance and efficiency of the central heat pump water heaters as a strategy to provide efficient electric water heating for net-zero all-electric buildings and where natural gas is not available on site. In addition, effectiveness of the quality assurance and quality control processes implemented to ensure proper system commissioning and to meet program participation requirements is evaluated. Recommendations for improvements that could improve successful implementation for large-scale, high performance communities are identified.

  18. West Village Community. Quality Management Processes and Preliminary Heat Pump Water Heater Performance

    Energy Technology Data Exchange (ETDEWEB)

    Dakin, B. [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); Backman, C. [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); Hoeschele, M. [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); German, A. [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States)

    2012-11-01

    West Village, a multi-use project underway at the University of California Davis, represents a ground-breaking sustainable community incorporating energy efficiency measures and on-site renewable generation to achieve community-level Zero Net Energy (ZNE) goals. When complete, the project will provide housing for students, faculty, and staff with a vision to minimize the community’s impact on energy use by reducing building energy use, providing on-site generation, and encouraging alternative forms of transportation. This focus of this research is on the 192 student apartments that were completed in 2011 under Phase I of the West Village multi-year project. The numerous aggressive energy efficiency measures implemented result in estimated source energy savings of 37% over the B10 Benchmark. There are two primary objectives of this research. The first is to evaluate performance and efficiency of the central heat pump water heaters as a strategy to provide efficient electric water heating for net-zero all-electric buildings and where natural gas is not available on site. In addition, effectiveness of the quality assurance and quality control processes implemented to ensure proper system commissioning and to meet program participation requirements is evaluated. Recommendations for improvements that could improve successful implementation for large-scale, high performance communities are identified.

  19. Report on International Collaboration Involving the FE Heater and HG-A Tests at Mont Terri

    Energy Technology Data Exchange (ETDEWEB)

    Houseworth, Jim [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Rutqvist, Jonny [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Asahina, Daisuke [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chen, Fei [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Vilarrasa, Victor [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Liu, Hui-Hai [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Birkholzer, Jens [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2013-11-01

    Nuclear waste programs outside of the US have focused on different host rock types for geological disposal of high-level radioactive waste. Several countries, including France, Switzerland, Belgium, and Japan are exploring the possibility of waste disposal in shale and other clay-rich rock that fall within the general classification of argillaceous rock. This rock type is also of interest for the US program because the US has extensive sedimentary basins containing large deposits of argillaceous rock. LBNL, as part of the DOE-NE Used Fuel Disposition Campaign, is collaborating on some of the underground research laboratory (URL) activities at the Mont Terri URL near Saint-Ursanne, Switzerland. The Mont Terri project, which began in 1995, has developed a URL at a depth of about 300 m in a stiff clay formation called the Opalinus Clay. Our current collaboration efforts include two test modeling activities for the FE heater test and the HG-A leak-off test. This report documents results concerning our current modeling of these field tests. The overall objectives of these activities include an improved understanding of and advanced relevant modeling capabilities for EDZ evolution in clay repositories and the associated coupled processes, and to develop a technical basis for the maximum allowable temperature for a clay repository.

  20. Study on Pot Forming of Induction Heater Type Rice Cookers by Forging Cast Process

    Science.gov (United States)

    Ohnishi, Masayuki; Yamaguchi, Mitsugi; Ohashi, Osamu

    This paper describes a study result on pot fabrication by the forging cast process of stainless steel with aluminum. Rice cooked with the new bowl-shaped pot for the induction heater type rice cookers is better tasting than rice cooked with the conventional cylindrical one, due to the achievement of better heat conduction and convection. The conventional pot is made of the clad sheet, consisting of stainless steel and aluminum. However, it is rather difficult to form a bowl shape from the clad sheet, primarily due to the problem of a material spring back. The fabrication of a new type of a pot was made possible by means of the adoption of a forging cast process instead of the clad sheet. In this process, iron powder is inserted between stainless steel and aluminum in order to alleviate the large difference on the coefficient of expansion between each material. It was made clear that the application of two kinds of iron particle, namely 10 μm size powder on the stainless steel side and 44 μm on the aluminum side, enables the joints to become strong enough. The joint strength of the new pot by this fabrication process was confirmed by the tests of the shear strength and the fatigue tests together with the stress analysis.

  1. Thermodynamic Analysis of a Steam Power Plant with Double Reheat and Feed Water Heaters

    Directory of Open Access Journals (Sweden)

    M. M. Rashidi

    2014-03-01

    Full Text Available A steam cycle with double reheat and turbine extraction is presented. Six heaters are used, three of them at high pressure and the other three at low pressure with deaerator. The first and second law analysis for the cycle and optimization of the thermal and exergy efficiencies are investigated. An exergy analysis is performed to guide the thermodynamic improvement for this cycle. The exergy and irreversibility analyses of each component of the cycle are determined. Effects of turbine inlet pressure, boiler exit steam temperature, and condenser pressure on the first and second laws' efficiencies are investigated. Also the best turbine extraction pressure on the first law efficiency is obtained. The results show that the biggest exergy loss occurs in the boiler followed by the turbine. The results also show that the overall thermal efficiency and the second law efficiency decrease as the condenser pressure increases for any fixed outlet boiler temperature, however, they increase as the boiler temperature increases for any condenser pressure. Furthermore, the best values of extraction pressure from high, intermediate, and low pressure turbine which give the maximum first law efficiencies are obtained based on the required heat load corresponding to each exit boiler temperature.

  2. Atomization of High-Viscosity Fluids for Aromatherapy Using Micro-heaters for Heterogeneous Bubble Nucleation.

    Science.gov (United States)

    Law, Junhui; Kong, Ka Wai; Chan, Ho-Yin; Sun, Winston; Li, Wen Jung; Chau, Eric Boa Fung; Chan, George Kak Man

    2017-01-11

    The development of a novel lead-free microelectromechanical-system (MEMS)-based atomizer using the principle of thermal bubble actuation is presented. It is a low-cost, lead-free design that is environmentally friendly and harmless to humans. It has been tested to be applicable over a wide range of fluid viscosities, ranging from 1 cP (e.g., water) to 200 cP (e.g., oil-like fluid) at room temperature, a range that is difficult to achieve using ordinary atomizers. The results demonstrate that the average power consumption of the atomizer is approximately 1 W with an atomization rate of 0.1 to 0.3 mg of deionized (DI) water per cycle. The relationships between the micro-heater track width and the track gap, the size of the micro-cavities and the nucleation energy were studied to obtain an optimal atomizer design. The particle image velocimetry (PIV) results indicate that the diameter of the ejected droplets ranges from 30 to 90 μm with a speed of 20 to 340 mm/s. In addition, different modes of spraying are reported for the first time. It is envisioned that the successful development of this MEMS-based atomizing technology will revolutionize the existing market for atomizers and could also benefit different industries, particularly in applications involving viscous fluids.

  3. Atomization of High-Viscosity Fluids for Aromatherapy Using Micro-heaters for Heterogeneous Bubble Nucleation

    Science.gov (United States)

    Law, Junhui; Kong, Ka Wai; Chan, Ho-Yin; Sun, Winston; Li, Wen Jung; Chau, Eric Boa Fung; Chan, George Kak Man

    2017-01-01

    The development of a novel lead-free microelectromechanical-system (MEMS)-based atomizer using the principle of thermal bubble actuation is presented. It is a low-cost, lead-free design that is environmentally friendly and harmless to humans. It has been tested to be applicable over a wide range of fluid viscosities, ranging from 1 cP (e.g., water) to 200 cP (e.g., oil-like fluid) at room temperature, a range that is difficult to achieve using ordinary atomizers. The results demonstrate that the average power consumption of the atomizer is approximately 1 W with an atomization rate of 0.1 to 0.3 mg of deionized (DI) water per cycle. The relationships between the micro-heater track width and the track gap, the size of the micro-cavities and the nucleation energy were studied to obtain an optimal atomizer design. The particle image velocimetry (PIV) results indicate that the diameter of the ejected droplets ranges from 30 to 90 μm with a speed of 20 to 340 mm/s. In addition, different modes of spraying are reported for the first time. It is envisioned that the successful development of this MEMS-based atomizing technology will revolutionize the existing market for atomizers and could also benefit different industries, particularly in applications involving viscous fluids. PMID:28074925

  4. Analysis of the traveling heater method for the growth of cadmium telluride

    Science.gov (United States)

    Peterson, Jeffrey H.; Fiederle, Michael; Derby, Jeffrey J.

    2016-11-01

    We discuss the development and implementation of a comprehensive mathematical model for the traveling heater method (THM) that is formulated to realistically represent the interactions of heat and species transport, fluid flow, and interfacial dissolution and growth under conditions of local thermodynamic equilibrium and steady-state growth. We examine the complicated interactions among zone geometry, continuum transport, phase change, and fluid flow driven by buoyancy. Of particular interest and importance is the formation of flow structures in the liquid zone of the THM that arise from the same physical mechanism as lee waves in atmospheric flows and demonstrate the same characteristic Brunt-Väisälä scaling. We show that flow stagnation and reversal associated with lee-wave formation are responsible for the accumulation of tellurium and supercooled liquid near the growth interface, even when the lee-wave vortex is not readily apparent in the overall flow structure. The supercooled fluid is posited to result in morphological instability at growth rates far below the limit predicted by the classical criterion by Tiller et al. for constitutional supercooling.

  5. Modelling of an ICS solar water heater using artificial neural networks and TRNSYS

    Energy Technology Data Exchange (ETDEWEB)

    Souliotis, M.; Tripanagnostopoulos, Y. [Physics Department, University of Patras, Patras 26504, ACHAIA (Greece); Kalogirou, S. [Department of Mechanical Engineering and Materials Science and Engineering, Cyprus University of Technology, P.O. Box 50329, Limassol 3603 (Cyprus)

    2009-05-15

    A study, in which a suitable artificial neural network (ANN) and TRNSYS are combined in order to predict the performance of an Integrated Collector Storage (ICS) prototype, is presented. Experimental data that have been collected from outdoor tests of an ICS solar water heater with cylindrical water storage tank inside a CPC reflector trough were used to train the ANN. The ANN is then used through the Excel interface (Type 62) in TRNSYS to model the annual performance of the system by running the model with the values of a typical meteorological year for Athens, Greece. In this way the specific capabilities of both approaches are combined, i.e., use of the radiation processing and modelling power of TRNSYS together with the 'black box' modelling approach of ANNs. The details of the calculation steps of both methods that aim to perform an accurate prediction of the system performance are presented and it is shown that this new method can be used effectively for such predictions. (author)

  6. Atomization of High-Viscosity Fluids for Aromatherapy Using Micro-heaters for Heterogeneous Bubble Nucleation

    Science.gov (United States)

    Law, Junhui; Kong, Ka Wai; Chan, Ho-Yin; Sun, Winston; Li, Wen Jung; Chau, Eric Boa Fung; Chan, George Kak Man

    2017-01-01

    The development of a novel lead-free microelectromechanical-system (MEMS)-based atomizer using the principle of thermal bubble actuation is presented. It is a low-cost, lead-free design that is environmentally friendly and harmless to humans. It has been tested to be applicable over a wide range of fluid viscosities, ranging from 1 cP (e.g., water) to 200 cP (e.g., oil-like fluid) at room temperature, a range that is difficult to achieve using ordinary atomizers. The results demonstrate that the average power consumption of the atomizer is approximately 1 W with an atomization rate of 0.1 to 0.3 mg of deionized (DI) water per cycle. The relationships between the micro-heater track width and the track gap, the size of the micro-cavities and the nucleation energy were studied to obtain an optimal atomizer design. The particle image velocimetry (PIV) results indicate that the diameter of the ejected droplets ranges from 30 to 90 μm with a speed of 20 to 340 mm/s. In addition, different modes of spraying are reported for the first time. It is envisioned that the successful development of this MEMS-based atomizing technology will revolutionize the existing market for atomizers and could also benefit different industries, particularly in applications involving viscous fluids.

  7. Energy Impacts of Oversized Residential Air Conditioners -- Simulation Study of Retrofit Sequence Impacts

    Energy Technology Data Exchange (ETDEWEB)

    Booten, C. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Christensen, C. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Winkler, J. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-11-01

    This research addresses the question of what are the energy consequences for oversizing of an air conditioner in a home. Conventional wisdom holds that oversizing the AC results in significant energy penalties. However, the reason for this was shown to be due to crankcase heaters and not due to cycling performance of the AC, and is only valid for a particular set of assumptions. Adding or removing individual characteristics, such as ducts or crankcase heaters, can have measurable impacts on energy use. However, with all other home characteristics held constant, oversizing the AC generally has a small effect on cooling energy use, even if the cycling performance of the unit is poor. The relevant aspects of air conditioner modeling are discussed to illustrate the effects of the cycling loss coefficient, Cd, capacity, climate, ducts and parasitic losses such as crankcase heaters. A case study of a typical 1960's vintage home demonstrates results in the context of whole building simulations using EnergyPlus.

  8. Molecular hydrogen (H2) combustion emissions and their isotope (D/H) signatures from domestic heaters, diesel vehicle engines, waste incinerator plants, and biomass burning

    Science.gov (United States)

    Vollmer, M. K.; Walter, S.; Mohn, J.; Steinbacher, M.; Bond, S. W.; Röckmann, T.; Reimann, S.

    2012-07-01

    Molecular hydrogen (H2), its stable isotope signature (δD), and the key combustion parameters carbon monoxide (CO), carbon dioxide (CO2), and methane (CH4) were measured from various combustion processes. H2 in the exhaust of gas and oil-fired heaters and of waste incinerator plants was generally depleted compared to ambient intake air, while CO was significantly elevated. These findings contradict the often assumed co-occurring net H2 and CO emissions in combustion processes and suggest that previous H2 emissions from combustion may have been overestimated when scaled to CO emissions. For the gas and oil-fired heater exhausts, H2 and δD generally decrease with increasing CO2, from ambient values of ~0.5 ppm and +130‰ to 0.2 ppm and -206‰, respectively. These results are interpreted as a combination of an isotopically light H2 source from fossil fuel combustion and a D/H kinetic isotope fractionation of hydrogen in the advected ambient air during its partial removal during combustion. Diesel exhaust measurements from dynamometer test stand driving cycles show elevated H2 and CO emissions during cold-start and some acceleration phases. While H2 and CO emissions from diesel vehicles are known to be significantly less than those from gasoline vehicles (on a fuel-energy base), we find that their molar H2/CO ratios (median 0.026, interpercentile range 0.12) are also significantly less compared to gasoline vehicle exhaust. Using H2/CO emission ratios, along with CO global emission inventories, we estimate global H2 emissions for 2000, 2005, and 2010. For road transportation (gasoline and diesel), we calculate 8.3 ± 2.2 Tg, 6.0 ± 1.5 Tg, and 3.8 ± 0.94 Tg, respectively, whereas the contribution from diesel vehicles is low (0.9-1.4%). Other fossil fuel emissions are believed to be negligible but H2 emissions from coal combustion are unknown. For residential (domestic) emissions, which are likely dominated by biofuel combustion, emissions for the same years are

  9. Optimized wood/pellet heater with flue gas condensation; Optimerad ved/pelletspanna med roekgaskondensering

    Energy Technology Data Exchange (ETDEWEB)

    Fredriksson, Christian; Ramstroem, Erik; Berge, Niklas [TPS Termiska Processer AB, Nykoeping (Sweden)

    2002-09-01

    To increase the efficiency of small-scale combustion equipment it is possible to cool the flue gas and condense the water vapor in the flue gas in a flue gas condenser. This also makes it possible to reduce the emissions of particles and unburnt hydrocarbon if the condenser is designed in a suitable way. This work concerns flue gas condensation with respect to the design of the condenser, the handling of the condensate and the integration of the flue gas condenser in a heating system from a technical and an economical point of view. The results from laboratory experiments shows that a flue gas condenser, designed as a plate heat exchanger, connected to a wood pellet fired heater reduces the emissions of both particles and unburnt hydrocarbons. A reduction of 10 to 77% of the particle content in the gas was achieved, the content of hydrocarbons (BTX) was reduced by 50 to 91 %. It was not possible to see any effect on the emissions by changing the design of the condenser, due to the relatively large scatter in the determined particle content in the gas. When it comes to cooling capacity the trends were however more clear; the cooling capacity was strongly dependent on the design of the condenser. It was possible to increase the cooling capacity of the condenser with 124% by changing the condenser design from a reference case with conventional design of the condenser with flat walls, to a design with a corrugated shape of the wall. For a typical domestic wood stove heater of 30 kW this means that the cooling capacity in a condenser under similar conditions increases from 3.3 to 7.4 kW. The addition of water in a spray in the gas upstream of the condenser had only a limited effect on the cooling capacity. The condensate from the condenser was analyzed with respect to the components that currently are regulated for disposal to the district sewer system. The analyses showed that the condensate most likely could be disposed to the sewer system directly without any

  10. The electrothermal feasibility of carbon microcoil heaters for cold/hot gas microthrusters

    Science.gov (United States)

    Williams, K. L.; Eriksson, A. B.; Thorslund, R.; Köhler, J.; Boman, M.; Stenmark, L.

    2006-07-01

    With the miniaturization of spacecraft the need for efficient, accurate and low-weight attitude control systems is becoming evident. To this end, the cold/hot gas microthruster system of this paper incorporates carbon microcoils—deposited via laser-induced chemical vapor deposition—for heating the propellant gas (nitrogen) before the nozzle inlet. By increasing the temperature of the propellant gas for such a system, the specific impulse (Isp) of the microthruster will increase. The benefits of a higher Isp are lower propellant mass, higher thrust and shorter burning times. Therefore, the feasibility of achieving this increase with the carbon microcoils is investigated. The carbon microcoils have been characterized experimentally with respect to their electrothermal performance, i.e. resistance, temperature, parasitic heat losses and degradation in ambient. The resulting heat losses from the heater and the heated gas have been estimated through a combination of experiments, numerical simulation and approximate analytical expressions. At high powers, degradation of the carbon material leads to coil failure in ambient where trace oxygen was present. Thus, the next generation of carbon microcoils to be tested will have a protective coating to extend their lifetime. Theoretical modeling showed that an increase in the propellant gas temperature from 300 to 1200 K and a corresponding two-fold increase in the Isp can be achieved if 1.0 W of power is supplied to each coil in a three-coil thruster. These simulation results show that if the coils are capable of dissipating 1 W of heat at 1700 K coil temperature, the doubling of the Isp may be achieved. Comparing to the electrothermal characterization results we find that the carbon coils can survive at 1700 K if protected, and that they can be expected to reach 1700 K at power below 1 W.

  11. Building America Case Study: Multifamily Central Heat Pump Water Heaters, Davis, California

    Energy Technology Data Exchange (ETDEWEB)

    2017-03-08

    Although heat pump water heaters (HPWHs) have gained significant attention in recent years as a high efficiency electric water heating solution for single family homes, central HPWHs for commercial or multi-family applications are not as well documented in terms of measured performance and cost effectiveness. To evaluate this technology, the Alliance for Residential Building Innovation team monitored the performance of a 10.5 ton central HPWH installed on a student apartment building at the West Village Zero Net Energy Community in Davis, California. Monitoring data collected over a 16-month period were then used to validate a TRNSYS simulation model. The TRNSYS model was then used to project performance in different climates using local electric rates. Results of the study indicate that after some initial commissioning issues, the HPWH operated reliably with an annual average efficiency of 2.12 (Coefficient of Performance). The observed efficiency was lower than the unit's rated efficiency, primarily due to the fact that the system rarely operated under steady-state conditions. Changes in the system configuration, storage tank sizing, and control settings would likely improve the observed field efficiency. Modeling results suggest significant energy savings relative to electric storage water heating systems (typical annual efficiencies around 0.90) providing for typical simple paybacks of six to ten years without any incentives. The economics versus gas water heating are currently much more challenging given the current low natural gas prices in much of the country. Increased market size for this technology would benefit cost effectiveness and spur greater technology innovation.

  12. Performance analysis of coated 238PuO2 fuel particles compact for radioisotope heater units

    Science.gov (United States)

    Tournier, Jean-Michel; El-Genk, Mohamed S.

    2000-01-01

    A fuel form consisting of coated plutonia fuel particles dispersed in a graphite matrix is being investigated for use in Radioisotope Heater Units (RHUs). The fuel particles consist of a 238PuO2 kernel (300-1200 μm in diameter), a 5-μm PyC inner coating and a ZrC outer coating (>=10 μm). The latter, an extremely strong material at high temperatures, serves as a pressure vessel for maintaining the integrity of the fuel particle and containing the helium generated by radioactive decay. Parametric analyses compared the thermal powers of the coated particle fuel compact (CPFC) RHU and LWRHU. Both utilize Fine-Weave Pierced Fabric (FWPF) aeroshell and PyC insulation sleeves. During normal operation, the fuel temperature is ~800 K, but could reach as much as 1723 K during an accidental re-entry heating. Assuming full helium release, a single-size particle (500 μm) fuel compact would maintain its integrity at a temperature of 1723 K, after 10 years storage time before launch. When replacing the LWRHU fuel pellet, Pt-alloy clad and inner PyC insulation sleeve with CPFC, the calculated thermal power of the CPFC-RHU is 1.5, 2.3 and 2.4 times that of LWRHU, for 100%, 10%, and 5% helium release, respectively, with little change in total mass. A fuel compact using binary-size particles (300 and 1200 μm diameters) would deliver 15% more thermal power. A one-dimensional, transient thermal analysis of the CPFC-RHU showed that during accidental re-entry the maximum fuel temperature in the CPFC would be 1734 K. .

  13. Coated particle fuel for radioisotope power systems and heater units: status and future research needs

    Science.gov (United States)

    El-Genk, Mohamed S.; Tournier, Jean-Michel; Sholtis, Joseph A.; Lipinski, Ronald J.

    2000-01-01

    Coated particle fuel has been proposed recently for use in Radioisotope Power Systems (RPSs) and Radioisotope Heater Units (RHUs) for a variety of space missions requiring power levels from mWs to 10's or even hundreds of Watts. It can be made into different shapes and sizes of solid compacts, heating tapes, or paints. Using a conservative design approach, this fuel form could increase by 2.3-2.4 times the thermal power output of a LWRHU, while offering promise of enhanced safety. These performance figures are based on using single-size (500 μm) compacts of ZrC coated 238PuO2 kernels and assuming 10% and 5% He release, respectively, at 1723 K, following 10 years of storage. Using binary-size (300 and 1200 μm) fuel kernels in the compact increases the thermal power output by an additional 15%. 238PuO2 fuel kernels are intentionally sized (>=300 μm in diameter) to prevent any adverse radiological effects. They are non-respirable and non-inhalable and, if ingested, would simply be excreted with no radiological effects. The 238PuO2 fuel kernels are contained within a strong ZrC coating, which is designed to fully retain the fuel and the helium gas. Helium retention in large grain (>=300 μm) granular and polycrystalline fuel kernels is possible even at high temperatures (>1700 K). The former could be fabricated using binderless agglomeration or similar processes, while the latter could be fabricated using Sol-Gel or thermal plasma processes, with potentially less radioactive waste and fabrication contamination. In addition to summarizing the results of a recent effort investigating the performance of coated fuel particle compact (CPFC) and helium gas release, this paper identifies and discusses future research and testing needs. .

  14. Recycling ash into the first stage of cyclone pre-heater of cement kiln.

    Science.gov (United States)

    Zhan, Ming-Xiu; Fu, Jian-Ying; Havukainen, Jouni; Chen, Tong; Li, Xiao-Dong; Yan, Jian-Hua; Buekens, Alfons

    2016-10-01

    Fly ash collected from the bag filter could be recycled into the first stage of the cyclone pre-heater of the cement kiln, resulting in the possible enrichment of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). In this study, soxhlet fly ash (SFA) and raw meal (RM) were selected as the basis for the PCDD/F formation experiments. The levels of 2,3,7,8-PCDD/Fs formed on the SFA and RM were observed to be 2550pg/g (157pg I-TEQ/g) and 1142pg/g (55pg I-TEQ/g), respectively. While less 2,3,7,8-PCDD/Fs was detected when SFA was mixed with RM, suggesting that recycling cement kiln ash would not largely increase the concentration of PCDD/Fs in flue gas. Furthermore, the possible influencing factors on the PCDD/F formation were also investigated. The formation of 2,3,7,8-PCDD/Fs was up to 10,871pg/g (380pg I-TEQ/g) with the adding of CuCl2, which was much higher than the results of CuO and activated carbon. Most importantly, the homologue, congener and gas/particle distribution of PCDD/Fs indicated that de novo synthesis was the dominant PCDD/F formation pathway for SFA. Lastly, principal component analysis (PCA) was also conducted to identify the relationship between the compositions of reactant and the properties of PCDD/Fs produced.

  15. 电厂表面式给水加热器瞬态特性模拟与分析%Research on Transient Performance of Closed Feedwater Heater

    Institute of Scientific and Technical Information of China (English)

    李爱娟; 郭喜燕; 杨志平

    2011-01-01

    加热器的运行特性决定回热系统的稳定性,进而影响着整个热力系统的性能.为了更好地了解加热器的运行,根据换热工质的不同,采用分段建模的方法,分别建立了加热器单相换热段和汽-液两相换热段的数学模型,进而得到表面式给水加热器的通用瞬态数学模型.对两类换热面分别建模相对于以凝结段模型代替整个加热器分析,精度较好.通过对两类换热模型的组合,既可以得到高压加热器模型又能组合成低压加热器模型.以高压加热器为例,模拟了给水流量变化时,给水出口温度、蒸汽侧流量、温度、压力的变化,并对结果进行了分析,了解给水参数变化对加热器运行特性的影响.%Operating characteristics of the heater affect the stability of regenerative system and thereby the performance of the whole thermal system. To understand the operation of the heater better, according to the different working fluids in the heat exchanger, using the modular modeling method, the mathematical models for single-phase heat transfer section and steam-liquid two-phase section of the heater were established, and then a common surface type transient mathematical model of the heater is obtained. Separate modeling for the two types of heating surface relative to that of the condensate section to replace the whole heater, the precision is improved. Through a combination of the two types of heat transfer model, the high pressure heater and the low pressure heater models were obtained. Taking a high pressure heater as an example, the simulation is applied to analyze changing progresses for working fluid flow, temperature and pressure under feedwater flow changes. This study shows how the change of feedwater parameter affects the heaters performance.

  16. Technique of optimization of minimum temperature driving forces in the heaters of regeneration system of a steam turbine unit

    Science.gov (United States)

    Shamarokov, A. S.; Zorin, V. M.; Dai, Fam Kuang

    2016-03-01

    At the current stage of development of nuclear power engineering, high demands on nuclear power plants (NPP), including on their economy, are made. In these conditions, improving the quality of NPP means, in particular, the need to reasonably choose the values of numerous managed parameters of technological (heat) scheme. Furthermore, the chosen values should correspond to the economic conditions of NPP operation, which are postponed usually a considerable time interval from the point of time of parameters' choice. The article presents the technique of optimization of controlled parameters of the heat circuit of a steam turbine plant for the future. Its particularity is to obtain the results depending on a complex parameter combining the external economic and operating parameters that are relatively stable under the changing economic environment. The article presents the results of optimization according to this technique of the minimum temperature driving forces in the surface heaters of the heat regeneration system of the steam turbine plant of a K-1200-6.8/50 type. For optimization, the collector-screen heaters of high and low pressure developed at the OAO All-Russia Research and Design Institute of Nuclear Power Machine Building, which, in the authors' opinion, have the certain advantages over other types of heaters, were chosen. The optimality criterion in the task was the change in annual reduced costs for NPP compared to the version accepted as the baseline one. The influence on the decision of the task of independent variables that are not included in the complex parameter was analyzed. An optimization task was decided using the alternating-variable descent method. The obtained values of minimum temperature driving forces can guide the design of new nuclear plants with a heat circuit, similar to that accepted in the considered task.

  17. Movement and evaporation of water droplets under conditions typical for heat-exchange chambers of contact water heaters

    Science.gov (United States)

    Volkov, R. S.; Kuznetsov, G. V.; Strizhak, P. A.

    2016-09-01

    The macroscopic regularities and integrated characteristics of the motion and evaporation of sprayed water droplets in the field of high-temperature (1100 K) combustion products under the conditions typical for water heaters of contact type (economizers) were studied using a cross-correlation complex working on the basis of panoramic optical methods (particle image velocimetry, particle tracking velocimetry, shadow photography) and high-speed (105 fps) Phantom video cameras. High-speed video recording devices with specialized software were used for continuously monitoring the motion and evaporation of droplets. Titanium dioxide nanopowder tracer particles were introduced to determine the rate of high-temperature gases. The characteristic distances covered by water droplets before their full retardation in the counter-flow of high-temperature combustion products were determined. The integrated dependences were obtained, and the main characteristics of evaporation were determined, which allow one to predict the intensity of the phase transformations of droplets (with sizes of 0.05-0.5 mm) and the distances covered by them before they completely turn in the opposite direction under the conditions corresponding to the heat-exchange chambers of contact water heaters: the vapor-droplet rate 1-5 m/s, gas flow rate 0.5-2 m/s, and gas temperature ~1100 K. Approximating expressions were derived to predict the characteristics of the processes. The performance of the economizers under study can be significantly increased by using the obtained experimental dependences, the corresponding approximating expressions, and the resulting conclusions. Conditions were determined under which the influence of phase transformations on retardation exceeds the contribution of the counter-motion and active retardation and evaporation of water droplets occur in the heat-exchange chambers of contact water heaters of typical sizes.

  18. Large capacity, multi-fuel, and high temperature working fluid heaters to optimize CSP plant cost, complexity and annual generation

    Science.gov (United States)

    Peterseim, J. H.; Viscuso, L.; Hellwig, U.; McIntyre, P.

    2016-05-01

    This paper analyses the potential to optimize high temperature fluid back-up systems for concentrating solar power (CSP) plants by investigating the cost impact of component capacity and the impact of using multiple fuels on annual generation. Until now back-up heaters have been limited to 20MWth capacity but larger units have been realised in other industries. Installing larger units yields economy-of-scale benefits through improved manufacturing, optimised transport, and minimized on-site installation work. Halving the number of back-up boilers can yield cost reduction of 23% while minimizing plant complexity and on-site construction risk. However, to achieve these benefits it is important to adapt the back-up heaters to the plant's requirements (load change, capacity, minimum load, etc.) and design for manufacture, transport and assembly. Despite the fact that biomass availability is decreasing with increasing direct normal irradiance (DNI), some biomass is available in areas suitable for CSP plants. The use of these biomass resources is beneficial to maximise annual renewable energy generation, substitute natural gas, and use locally/seasonally available biomass resources that may not be used otherwise. Even small biomass quantities of only 50,000 t/a can increase the capacity factor of a 50MWe parabolic trough plant with 7h thermal energy storage from 40 to 49%. This is a valuable increase and such a concept is suitable for new plants and retrofit applications. However, similar to the capacity optimisation of back-up heaters, various design criteria have to be considered to ensure a successful project.

  19. Simply and reliably integrating micro heaters/sensors in a monolithic PCR-CE microfluidic genetic analysis system.

    Science.gov (United States)

    Zhong, Runtao; Pan, Xiaoyan; Jiang, Lei; Dai, Zhongpeng; Qin, Jianhua; Lin, Bingcheng

    2009-04-01

    A novel fabrication process was presented to construct a monolithic integrated PCR-CE microfluidic DNA analysis system as a step toward building a total genetic analysis microsystem. Microfabricated Titanium/Platinum (Ti/Pt) heaters and resistance temperature detectors (RTDs) were integrated on the backside of a bonded glass chip to provide good thermal transfer and precise temperature detection for the drilled PCR-wells. This heater/RTD integration procedure was simple and reliable, and the resulting metal layer can be easily renewed when the Ti/Pt layer was damaged in later use or novel heater/RTD design was desired. A straightforward "RTD-calibration" method was employed to optimize the chip-based thermal cycling conditions. This method was convenient and rapid, comparing with a conventional RTD-calibration/temperature adjustment method. The highest ramping rates of 14 degrees C/s for heating and 5 degrees C/s for cooling in a 3-microL reaction volume allow 30 complete PCR cycles in about 33 min. After effectively passivating the PCR-well surface, successful lambda-phage DNA amplifications were achieved using a two- or three-temperature cycling protocol. The functionality and performance of the integrated microsystem were demonstrated by successful amplification and subsequent on-line separation/sizing of lambda-phage DNA. A rapid assay for Hepatitis B virus, one of the major human pathogens, was performed in less than 45 min, demonstrating that the developed PCR-CE microsystem was capable of performing automatic and high-speed genetic analysis.

  20. Air Pollution

    Science.gov (United States)

    ... to view this content or go to source URL . What NIEHS is Doing on Air Pollution Who ... Junction Last Reviewed: February 06, 2017 This page URL: NIEHS website: https://www.niehs.nih.gov/ Email ...