WorldWideScience

Sample records for conditioners water heaters

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

    International Nuclear Information System (INIS)

    Techarungpaisan, P.; Theerakulpisut, S.; Priprem, S.

    2007-01-01

    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

  2. Utilization of air conditioner condenser as water heater in an effort to energy conservation

    Science.gov (United States)

    Sonawan, Hery; Saputro, Panji; Kurniawan, Iden Muhtar

    2018-04-01

    This paper presents an experimental study of utilization of air conditioner condenser as water heater. Modification of existing air conditioner system is an effort to harvest waste heat energy from condenser. Modification is conducted in order to test the system into two mode tests, first mode with one condenser and second mode with two condensers. Harvesting the waste heat from condenser needs a theoretical and practice study to see how much the AC performance changes if modifications are made. It should also be considered how the technique of harvesting waste heat for water heating purposes. From the problem, this paper presents a comparison between AC performance before and after modification. From the experiment, an increase in compressor power consumption is 4.3% after adding a new condenser. The hot water temperature is attained to 69 °C and ready for warm bath. The increase in power consumption is not too significant compared to the attainable hot water temperature. Also seen that the value of condenser Performance Factor increase from 5.8 to 6.25 or by 7.8%.

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

    International Nuclear Information System (INIS)

    Wang Shaowei; Liu Zhenyan; Li Yuan; Zhao Keke; Wang Zhigang

    2005-01-01

    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

  4. Experimental study on the performance of a multi-functional domestic air conditioner with integrated water heater

    International Nuclear Information System (INIS)

    Dong, Jiankai; Li, Hui; Yao, Yang; Jiang, Yiqiang; Zhang, Xinran

    2017-01-01

    Highlights: • A novel MDACWH was presented and experimentally studied. • MDACWH has high performance on making domestic hot water and air conditioning. • The time for heating water reduced to 22.0 min after modification. • Average COP reached 4.32, which was 1.58 times higher than the unmodified unit. - Abstract: The recovery of condenser heat is concerned one of the most effective methods to curb energy consumption in residential dwellings. Aiming at recovering the condenser heat of domestic air conditioner, this paper experimentally studied a multi-functional domestic air conditioner with integrated water heater (MDACWH) which can effectively provide space – cooling and domestic hot water simultaneously. The dynamic operation characteristics, such as hot water supply and energy efficiency were tested to verify the availability of the MDACWH. The results showed that the MDACWH can effectively heat the domestic hot water without losing its cooling capacity. It was also found that with the use of MDACWH, the coefficient of comprehensive energy performance of the MDACWH was about 1.58 times higher than that of the unmodified experimental unit. Furthermore, the water-heating time was shorten remarkably from 128.5 min to 22.0 min. The novel domestic air conditioner, compared with the unmodified initial prototype, can be more practical and provide significant energy savings in space-cooling and hot water supply.

  5. Effect of heat recovery water heater system on the performance of residential split air conditioner using hydrocarbon refrigerant (HCR22)

    Science.gov (United States)

    Aziz, A.; Thalal; Amri, I.; Herisiswanto; Mainil, A. K.

    2017-09-01

    This This paper presents the performance of residential split air conditioner (RSAC) using hydrocarbon refrigerant (HCR22) as the effect on the use of heat recovery water heater system (HRWHS). In this study, RSAC was modified with addition of dummy condenser (trombone coil type) as heat recovery water heater system (HRWHS). This HRWHS is installed between a compressor and a condenser by absorbing a part of condenser waste heat. The results show that RSAC with HRWHS is adequate to generate hot water with the temperature range about 46.58˚C - 48.81˚C when compared to without HRWHS and the use of dummy condenser does not give significant effect to the split air conditioner performance. When the use of HRWHS, the refrigerant charge has increase about 19.05%, the compressor power consumption has slightly increase about 1.42% where cooling capacity almost the same with slightly different about 0.39%. The condenser heat rejection is lower about 2.68% and the COP has slightly increased about 1.05% when compared to without HRWHS. The use of HRWHS provide free hot water, it means there is energy saving for heating water without negative impact to the system performance of RSAC.

  6. 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.

  7. 78 FR 7394 - Notification of Proposed Production Activity; GE Appliances; Subzone 29C (Electric Water Heaters...

    Science.gov (United States)

    2013-02-01

    ..., freezers, apparel washing machines and dryers, electric ranges, and air-conditioners, under FTZ procedures...), fan motors, fans, filter/ dryers, expansion valves, accumulators, parts of electric water heaters...

  8. 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.

  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. Solar Hot Water Heater

    Science.gov (United States)

    1978-01-01

    The solar panels pictured below, mounted on a Moscow, Idaho home, are part of a domestic hot water heating system capable of providing up to 100 percent of home or small business hot water needs. Produced by Lennox Industries Inc., Marshalltown, Iowa, the panels are commercial versions of a collector co-developed by NASA. In an effort to conserve energy, NASA has installed solar collectors at a number of its own facilities and is conducting research to develop the most efficient systems. Lewis Research Center teamed with Honeywell Inc., Minneapolis, Minnesota to develop the flat plate collector shown. Key to the collector's efficiency is black chrome coating on the plate developed for use on spacecraft solar cells, the coating prevents sun heat from "reradiating," or escaping outward. The design proved the most effective heat absorber among 23 different types of collectors evaluated in a Lewis test program. The Lennox solar domestic hot water heating system has three main components: the array of collectors, a "solar module" (blue unit pictured) and a conventional water heater. A fluid-ethylene glycol and water-is circulated through the collectors to absorb solar heat. The fluid is then piped to a double-walled jacket around a water tank within the solar module.

  11. Solar water heaters in Taiwan

    International Nuclear Information System (INIS)

    Chang, K.; Lee, T.; Chung, K.

    2006-01-01

    Solar water heater has been commercialized during the last two decades in Taiwan. The government initiated the incentive programs during 1986-1991 and 2000-2004. This created an economic incentive for the end-users. The total area of solar collectors installed was more than one million square meters. The data also show that most of the solar water heaters are mainly used by the domestic sector for hot water production (about 97%). The regional popularization analysis indicates limited installation of solar water heaters in the northern district. In the eastern district and remote islands, the problems of climatic conditions and availability of localized installers/dealers are addressed. (author)

  12. 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 gallons...

  13. 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 454...

  14. Solar Water Heater Installation Package

    Science.gov (United States)

    1982-01-01

    A 48-page report describes water-heating system, installation (covering collector orientation, mounting, plumbing and wiring), operating instructions and maintenance procedures. Commercial solar-powered water heater system consists of a solar collector, solar-heated-water tank, electrically heated water tank and controls. Analysis of possible hazards from pressure, electricity, toxicity, flammability, gas, hot water and steam are also included.

  15. Molded polymer solar water heater

    Science.gov (United States)

    Bourne, Richard C.; Lee, Brian E.

    2004-11-09

    A solar water heater has a rotationally-molded water box and a glazing subassembly disposed over the water box that enhances solar gain and provides an insulating air space between the outside environment and the water box. When used with a pressurized water system, an internal heat exchanger is integrally molded within the water box. Mounting and connection hardware is included to provide a rapid and secure method of installation.

  16. Solar water heater design package

    Science.gov (United States)

    1981-01-01

    Package describes commercial domestic-hot-water heater with roof or rack mounted solar collectors. System is adjustable to pre-existing gas or electric hot-water house units. Design package includes drawings, description of automatic control logic, evaluation measurements, possible design variations, list of materials and installation tools, and trouble-shooting guide and manual.

  17. Solar Water Heater

    Science.gov (United States)

    1993-01-01

    As a Jet Propulsion Laboratory (JPL) scientist Dr. Eldon Haines studied the solar energy source and solar water heating. He concluded he could build a superior solar water heating system using the geyser pumping principle. He resigned from JPL to develop his system and later form Sage Advance Corporation to market the technology. Haines' Copper Cricket residential system has no moving parts, is immune to freeze damage, needs no roof-mounted tanks, and features low maintenance. It provides 50-90 percent of average hot water requirements. A larger system, the Copper Dragon, has been developed for commercial installations.

  18. Space Station solar water heater

    Science.gov (United States)

    Horan, D. C.; Somers, Richard E.; Haynes, R. D.

    1990-01-01

    The feasibility of directly converting solar energy for crew water heating on the Space Station Freedom (SSF) and other human-tended missions such as a geosynchronous space station, lunar base, or Mars spacecraft was investigated. Computer codes were developed to model the systems, and a proof-of-concept thermal vacuum test was conducted to evaluate system performance in an environment simulating the SSF. The results indicate that a solar water heater is feasible. It could provide up to 100 percent of the design heating load without a significant configuration change to the SSF or other missions. The solar heater system requires only 15 percent of the electricity that an all-electric system on the SSF would require. This allows a reduction in the solar array or a surplus of electricity for onboard experiments.

  19. Experimental Analysis on Solar Desiccant Air Conditioner

    OpenAIRE

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

    2014-01-01

    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 wou...

  20. 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.

  1. 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.

  2. Outlook for solar water heaters in Taiwan

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Keh-Chin [Department of Aeronautical and Astronautical Engineering, National Cheng Kung University, Kueijen, Tainan, Taiwan 711 (China); Lee, Tsong-Sheng; Chung, Kung-Ming [Aerospace Science and Technology Research Center, National Cheng Kung University, Kueijen, Tainan, Taiwan 711 (China); Lin, Wei-Min [Tainan University of Technology (China)

    2008-01-15

    The share of indigenous energy supply continuously decreases over the last two decades in Taiwan. The development and use of renewable energy sources and technologies are becoming vital for the management of energy supply and demand. For promotion of solar water heaters, the incentive programs were firstly initiated in the period of 1986-1991 and re-initiated from 2000 to the present. These programs create an economic incentive for the end users and have a drastic effect on the popularization of solar water heaters. To further promote solar water heaters during the current incentive program period, several key factors are addressed. In addition to the cost of solar water heaters and energy price index, the potential market of solar water heaters in Taiwan is associated with the climatic conditions, population structure, urbanization, building type of housing and status of new construction. (author)

  3. Outlook for solar water heaters in Taiwan

    International Nuclear Information System (INIS)

    Chang, Keh-Chin; Lee, Tsong-Sheng; Chung, Kung-Ming; Lin, Wei-Min

    2008-01-01

    The share of indigenous energy supply continuously decreases over the last two decades in Taiwan. The development and use of renewable energy sources and technologies are becoming vital for the management of energy supply and demand. For promotion of solar water heaters, the incentive programs were firstly initiated in the period of 1986-1991 and re-initiated from 2000 to the present. These programs create an economic incentive for the end users and have a drastic effect on the popularization of solar water heaters. To further promote solar water heaters during the current incentive program period, several key factors are addressed. In addition to the cost of solar water heaters and energy price index, the potential market of solar water heaters in Taiwan is associated with the climatic conditions, population structure, urbanization, building type of housing and status of new construction. (author)

  4. Water hammers in direct contact heater systems

    International Nuclear Information System (INIS)

    Uffer, R.

    1983-01-01

    This paper discusses the causes and mitigation or prevention of water hammers occurring in direct contact heaters and their attached lines. These water hammers are generally caused by rapid pressure reductions in the heaters or by water lines not flowing full. Proper design and operating measures can prevent or mitigate water hammer occurrence. Water hammers often do not originate at the areas where damage is noted

  5. Solar Water-Heater Design Package

    Science.gov (United States)

    1982-01-01

    Information on a solar domestic-hot water heater is contained in 146 page design package. System consists of solar collector, storage tanks, automatic control circuitry and auxiliary heater. Data-acquisition equipment at sites monitors day-by-day performance. Includes performance specifications, schematics, solar-collector drawings and drawings of control parts.

  6. Air Conditioner/Dehumidifier

    Science.gov (United States)

    1986-01-01

    An ordinary air conditioner in a very humid environment must overcool the room air, then reheat it. Mr. Dinh, a former STAC associate, devised a heat pipe based humidifier under a NASA Contract. The system used heat pipes to precool the air; the air conditioner's cooling coil removes heat and humidity, then the heat pipes restore the overcooled air to a comfortable temperature. The heat pipes use no energy, and typical savings are from 15-20%. The Dinh Company also manufactures a "Z" coil, a retrofit cooling coil which may be installed on an existing heater/air conditioner. It will also provide free hot water. The company has also developed a photovoltaic air conditioner and solar powered water pump.

  7. Solar Water-Heater Design and Installation

    Science.gov (United States)

    Harlamert, P.; Kennard, J.; Ciriunas, J.

    1982-01-01

    Solar/Water heater system works as follows: Solar--heated air is pumped from collectors through rock bin from top to bottom. Air handler circulates heated air through an air-to-water heat exchanger, which transfers heat to incoming well water. In one application, it may reduce oil use by 40 percent.

  8. Solar water heater for NASA's Space Station

    Science.gov (United States)

    Somers, Richard E.; Haynes, R. Daniel

    1988-01-01

    The feasibility of using a solar water heater for NASA's Space Station is investigated using computer codes developed to model the Space Station configuration, orbit, and heating systems. Numerous orbit variations, system options, and geometries for the collector were analyzed. Results show that a solar water heater, which would provide 100 percent of the design heating load and would not impose a significant impact on the Space Station overall design is feasible. A heat pipe or pumped fluid radial plate collector of about 10-sq m, placed on top of the habitat module was found to be well suited for satisfying water demand of the Space Station. Due to the relatively small area required by a radial plate, a concentrator is unnecessary. The system would use only 7 to 10 percent as much electricity as an electric water-heating system.

  9. 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.

  10. 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.

  11. 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.

  12. Solar water heaters in China. A new day dawning

    International Nuclear Information System (INIS)

    Han, Jingyi; Mol, Arthur P.J.; Lu, Yonglong

    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 affluent province, as a case study area to assess the performance of solar water heater utilization in China. The study will focus on institutional setting, economic and technological performance, energy performance, and environmental and social impact. Results show that China has greatly increased solar water heater utilization, which has brought China great economic, environmental and social benefits. However, China is confronted with malfeasant market competition, technical flaws in solar water heater products and social conflict concerning solar water heater installation. For further development of the solar water heater, China should clarify the compulsory installation policy and include solar water heaters into the current 'Home Appliances Going to the Countryside' project; most of the widely used vacuum tube products should be replaced by flat plate products, and the technology improvement should focus on anti-freezing and water saving; the resources of solar water heater market should be consolidated and most of the OEM manufacturers should evolve to ODM and OBM enterprises. (author)

  13. Preheating Water In The Covers Of Solar Water Heaters

    Science.gov (United States)

    Bhandari, Pradeep

    1995-01-01

    Solar water heaters that include glass covers over absorber plates redesigned to increase efficiencies according to proposal. Redesign includes modification of single-layer glass cover into double-layer glass cover and addition of plumbing so cool water to be heated made to flow between layers of cover before entering absorber plate.

  14. Multifamily Heat Pump Water Heater Evaluation

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-11-22

    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.

  15. 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.

  16. Multifamily Heat Pump Water Heater Evaluation

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-03-01

    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.

  17. Experimental Research of a Water-Source Heat Pump Water Heater System

    OpenAIRE

    Zhongchao Zhao; Yanrui Zhang; Haojun Mi; Yimeng Zhou; Yong Zhang

    2018-01-01

    The heat pump water heater (HPWH), as a portion of the eco-friendly technologies using renewable energy, has been applied for years in developed countries. Air-source heat pump water heaters and solar-assisted heat pump water heaters have been widely applied and have become more and more popular because of their comparatively higher energy efficiency and environmental protection. Besides use of the above resources, the heat pump water heater system can also adequately utilize an available wat...

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

    International Nuclear Information System (INIS)

    Symmetrics Marketing Corporation

    1999-01-01

    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

  19. 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.

  20. 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.

  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. South Africa. Fertile ground for solar water heaters

    Energy Technology Data Exchange (ETDEWEB)

    Oirere, Shem

    2012-07-01

    The national solar water heating plan, launched by South Africa's state power utility Eskom, seems to be making good progress with the power generator saying at least 215,000 solar water heater (SWH) systems had been installed by February this year. (orig.)

  3. NORTH PORTAL - WATER HEATER CALCULATION - CHANGE HOUSE FACILITY No.5008

    International Nuclear Information System (INIS)

    R.B. Blackstone

    1996-01-01

    The purpose of this design analysis and calculation is to determine the demand for hot water in the Change House Facility and the selection of a water heater of appropriate size in accordance with the Uniform Plumbing Code (Section 4.4.1) and U.S. Department of Energy Order 6430.1A-1540 (Section 4.4.2)

  4. 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.

  5. Assessment of a Hybrid Retrofit Gas Water Heater

    Energy Technology Data Exchange (ETDEWEB)

    Hoeschele, Marc [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); Weitzel, Elizabeth [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); Backman, Christine [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States)

    2017-02-01

    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.

  6. 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

  7. Marketing and promoting solar water heaters to home builders

    Energy Technology Data Exchange (ETDEWEB)

    Keller, C.; Ghent, P.

    1999-12-06

    This is the final report of a four-task project to develop a marketing plan designed for businesses interested in marketing solar water heaters in the new home industry. This report outlines suggested marketing communication materials and other promotional tools focused on selling products to the new home builder. Information relevant to promoting products to the new home buyer is also included.

  8. 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).

  9. 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.

  10. 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.

  11. 77 FR 74559 - Energy Conservation Program for Consumer Products: Test Procedures for Residential Water Heaters...

    Science.gov (United States)

    2012-12-17

    ... Conservation Program for Consumer Products: Test Procedures for Residential Water Heaters, Direct Heating... Energy (DOE) is amending its test procedures for residential water heaters, direct heating equipment (DHE... necessary for residential water heaters, because the existing test procedures for those products already...

  12. 76 FR 56347 - Energy Conservation Program for Consumer Products: Test Procedures for Residential Water Heaters...

    Science.gov (United States)

    2011-09-13

    ... Conservation Program for Consumer Products: Test Procedures for Residential Water Heaters, Direct Heating... proposed to amend, where appropriate, its test procedures for residential water heaters, direct heating... notes that the test procedure and metric for residential water heaters currently address and incorporate...

  13. 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.

  14. 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).

  15. Actual performance and economic feasibility of residential solar water heaters

    International Nuclear Information System (INIS)

    Anhalt, J.

    1987-01-01

    Four residential solar water heaters currently available on the Brazilian market have been evaluated to their possible use for substituting the common electric shower head. The tests were carried out with the solar systems mounted side by side on an artificial roof. The hot water demand was simulated following a consumer profile which represents a Brazilian family with an income of seven minimum salaries. The data, which was collected automatically and presented in the form of graphs and tables, shows that an optimized solar water heater could save as much as 65% of the energy demand for residential water heating in the state of Sao Paulo. An economical study concludes that the installation and maintenance of such a solar system is feasible if long term financing is available. (author)

  16. Heat exchanger for solar water heaters

    Science.gov (United States)

    Cash, M.; Krupnick, A. C.

    1977-01-01

    Proposed efficient double-walled heat exchanger prevents contamination of domestic water supply lines and indicates leakage automatically in solar as well as nonsolar heat sources using water as heat transfer medium.

  17. Feed water pre-heater with two steam spaces

    International Nuclear Information System (INIS)

    Tratz, H.; Kelp, F.; Netsch, E.

    1976-01-01

    A feed water pre-heater for the two stage heating of feed water by condensing steam, having a low installed height is described, which can be installed in the steam ducts of turbines of large output, as in LWRs in nuclear power stations. The inner steam space is closed on one side by the water vessel, while the tubes of the inner steam space go straight from the water vessel, and the tubes of the outer steam space are bent into a U shape and open out into the water vessel. The two-stage preheater is thus surrounded by feedwater in two ways. (UWI) [de

  18. 10 CFR 431.102 - Definitions concerning commercial water heaters, hot water supply boilers, and unfired hot water...

    Science.gov (United States)

    2010-01-01

    ... supply boilers, and unfired hot water storage tanks. 431.102 Section 431.102 Energy DEPARTMENT OF ENERGY... Water Heaters, Hot Water Supply Boilers and Unfired Hot Water Storage Tanks § 431.102 Definitions concerning commercial water heaters, hot water supply boilers, and unfired hot water storage tanks. The...

  19. Efficient low static-volume water heater

    Science.gov (United States)

    Brown, R. L.

    1976-01-01

    Calrod heating element is surrounded by matrix of fused sintered copper or brass balls, and assembly is then installed in piping of water system. As water flows through matrix, sintered balls cause turbulent flow and heating. Applications include laundromats, laboratories, and photographic labs.

  20. Experimentation of a Solar Water Heater with Integrated Storage Tank

    International Nuclear Information System (INIS)

    Elhmidi, I; Frikha, N; Chaouchi, B; Gabsi, S

    2009-01-01

    An integrated collector storage (ICS) solar water heater was constructed in 2004 and studied its optical and thermal performance. It was revealed that it has some thermal shortcomings of thermal performances. The ICS system consists of one cylindrical horizontal tank properly mounted in a stationary symmetrical Compound Parabolic Concentrating (CPC) reflector trough. The main objective was to delimit the causes of these deficiencies and trying to diagnose them. A rigorous experimentation of the solar water heater has been done over its daily energetic output as well as the evolution of the nocturnal thermal losses. In fact, three successive days, including nights, of operation have permitted to obtain diagrams describing the variations of mean temperature in the tank and the thermal loss coefficient during night of our installation. The experimental results, compared with those obtained by simulation, showed a perfecting of thermal performances of system which approach from those of other models introduced on the international market

  1. Performance test for a solar water heater

    Science.gov (United States)

    1979-01-01

    Two reports describe procedures and results of performance tests on domestic solar powered hot water system. Performance tests determine amount of energy collected by system, amount of energy delivered to solar source, power required to operate system and maintain proper tank temperature, overall system efficiency, and temperature distribution in tank.

  2. Electric Water Heater Modeling and Control Strategies for Demand Response

    Energy Technology Data Exchange (ETDEWEB)

    Diao, Ruisheng; Lu, Shuai; Elizondo, Marcelo A.; Mayhorn, Ebony T.; Zhang, Yu; Samaan, Nader A.

    2012-07-22

    Abstract— Demand response (DR) has a great potential to provide balancing services at normal operating conditions and emergency support when a power system is subject to disturbances. Effective control strategies can significantly relieve the balancing burden of conventional generators and reduce investment on generation and transmission expansion. This paper is aimed at modeling electric water heaters (EWH) in households and tests their response to control strategies to implement DR. The open-loop response of EWH to a centralized signal is studied by adjusting temperature settings to provide regulation services; and two types of decentralized controllers are tested to provide frequency support following generator trips. EWH models are included in a simulation platform in DIgSILENT to perform electromechanical simulation, which contains 147 households in a distribution feeder. Simulation results show the dependence of EWH response on water heater usage . These results provide insight suggestions on the need of control strategies to achieve better performance for demand response implementation. Index Terms— Centralized control, decentralized control, demand response, electrical water heater, smart grid

  3. 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.

  4. Experimental Research of a Water-Source Heat Pump Water Heater System

    Directory of Open Access Journals (Sweden)

    Zhongchao Zhao

    2018-05-01

    Full Text Available The heat pump water heater (HPWH, as a portion of the eco-friendly technologies using renewable energy, has been applied for years in developed countries. Air-source heat pump water heaters and solar-assisted heat pump water heaters have been widely applied and have become more and more popular because of their comparatively higher energy efficiency and environmental protection. Besides use of the above resources, the heat pump water heater system can also adequately utilize an available water source. In order to study the thermal performance of the water-source heat pump water heater (WSHPWH system, an experimental prototype using the cyclic heating mode was established. The heating performance of the water-source heat pump water heater system, which was affected by the difference between evaporator water fluxes, was investigated. The water temperature unfavorably exceeded 55 °C when the experimental prototype was used for heating; otherwise, the compressor discharge pressure was close to the maximum discharge temperature, which resulted in system instability. The evaporator water flux allowed this system to function satisfactorily. It is necessary to reduce the exergy loss of the condenser to improve the energy utilization of the system.

  5. A solar assisted heat-pump dryer and water heater

    International Nuclear Information System (INIS)

    Hawlader, M.N.A.; Chou, S.K.; Jahangeer, K.A.; Rahman, S.M.A.

    2006-01-01

    Growing concern about the depletion of conventional energy resources has provided impetus for considerable research and development in the area of alternative energy sources. A solar assisted heat pump dryer and water heater found to be one of the solutions while exploring for alternative energy sources. The heat pump system is used for drying and water heating applications with the major share of the energy derived from the sun and the ambient. The solar assisted heat pump dryer and water heater has been designed, fabricated and tested. The performance of the system has been investigated under the meteorological conditions of Singapore. The system consists of a variable speed reciprocating compressor, evaporator-collector, storage tank, air cooled condenser, auxiliary heater, blower, dryer, dehumidifier, and air collector. The drying medium used is air and the drying chamber is configured to carry out batch drying of good grains. A water tank connected in series with the air cooled condenser delivers hot water for domestic applications. The water tank also ensures complete condensation of the refrigerant vapour. A simulation program is developed using Fortran language to evaluate the performance of the system and the influence of different variables. The performance indices considered to evaluate the performance of the system are: Solar Fraction (SF), Coefficient of Performance (COP) and Specific Moisture Extraction Rate (SMER). A COP value of 7.5 for a compressor speed of 1800 rpm was observed. Maximum collector efficiencies of 0.86 and 0.81 have been found for evaporator-collector and air collector, respectively. A value of the SMER of 0.79 has been obtained for a load of 20 kg and a compressor speed of 1200 rpm

  6. An overview of the development of solar water heater industry in China

    International Nuclear Information System (INIS)

    Runqing, Hu; Peijun, Sun; Zhongying, Wang

    2012-01-01

    This article introduce the development of China solar water heater industry .Gives an overview of stages, market, manufacturing, application and testing about China solar water heater industry. Show the market data from 1998 to 2009. Analyze the experiences and features about the industry. The article also introduces the policy for solar hot water industry in China. These policies have accelerated the development of industry in which the main two incentive policies have the greatest influence on solar water heater industry. First one is the policy of mandatory installation of solar water heater implemented since 2007 by some local governments at provincial and municipal levels. Second is the subsidy policy for solar water heaters in the household appliances going to the countryside scheme implemented since 2009. At last the article gives the reason why China solar water heater industry have so rapid growth. From technology research, industrialization, prices and policy environment gives analysis. - Highlights: ► We compared International and China market about solar thermal products. ► The reason for rapid development of China solar water heater is explained. ► The experience of China solar water heater industry would give reference to other develop country. ► “Meet the demands of customer” is the main driver for the solar water heater industry development. ► The policy framework about China solar thermal industry was introduced. The industry achieved commercial operation without subsidy.

  7. The effect of sealer and water storage on permanent deformation of a tissue conditioner

    Directory of Open Access Journals (Sweden)

    Rafael Leonardo Xediek Consani

    2008-01-01

    Full Text Available When they are used to treat inflamed, irritated, or distorted tissues or in implant therapy, tissue conditioners are required to function over relatively long time periods. Purpose: This in vitro study evaluated the effect of sealer and water storage on permanent deformation one tissue conditioner. Material and methods: Sixty cylindrically-shaped specimens (12.7-mm diameter 3 19.0-mm height were used for the deformation tests. Specimens were divided into 6 test groups (n=10, according to surface treatment (sealer application and water storage (1 hour, 1 week and 2 weeks. Permanent deformation, expressed as a percent (%, was determined using ADA specification no. 18. Data were examined a analysis of variance and a Mann-Whitney test (a= 0.05. Results: Significant differences were observed only after 1 week of water storage, for both groups. The surface treated group presented the highest permanent deformation percentage. Conclusions: This in vitro study indicated that the tissue conditioner evaluated is only useful for 1 week. After this period, the material must be replaced.

  8. Subsidy programs on diffusion of solar water heaters: Taiwan's experience

    International Nuclear Information System (INIS)

    Chang, Keh-Chin; Lin, Wei-Min; Lee, Tsong-Sheng; Chung, Kung-Ming

    2011-01-01

    Financial incentives are essentially one of the key factors influencing diffusion of solar water heaters in many countries. Two subsidy programs were initiated by the government of Taiwan in 1986 (1986-1991) and 2000 (2000-present), respectively. Those long-term national programs are considered to be the driving force on local market expansion. In 2008, the regional subsidy programs for solar water heaters were announced by Kaohsiung city and Kiemen county, which resulted in the growth in sales. A revised subsidy was also initiated by the government of Taiwan in 2009. The subsidy is 50% more. However, the tremendous enlargement of market size with a high-level ratio of subsidy over total installation cost might result in a negative impact on a sustainable SWH industry and long-term development of the local market, which is associated with system design and post-installation service. This paper aims to address the relative efficiency and pitfalls of those national and regional programs. - Research Highlights: → The direct subsidy has been the driving force on market expansion in Taiwan. → Higher subsidy would certainly increase the total number of systems installed. → A high-level subsidy results in a negative impact on users or a sustainable industry.

  9. 75 FR 20111 - Energy Conservation Program: Energy Conservation Standards for Residential Water Heaters, Direct...

    Science.gov (United States)

    2010-04-16

    ... Program: Energy Conservation Standards for Residential Water Heaters, Direct Heating Equipment, and Pool... heating equipment and pool heaters. Table I.1--Amended Energy Conservation Standards for Residential Water... for national energy and water conservation; and 7. Other factors the Secretary of Energy (Secretary...

  10. Energy efficiency improvement and fuel savings in water heaters using baffles

    International Nuclear Information System (INIS)

    Moeini Sedeh, Mahmoud; Khodadadi, J.M.

    2013-01-01

    Highlights: ► Thermal efficiency improved by simple/novel design of baffles inside water reservoir. ► Noticeable steady-state natural gas savings of about 5%. ► Extensive 3-D numerical investigations followed by experimental verifications. ► Baffle designs prototyped in identical water heaters for ANSI/US DOE test protocols. ► Numerical/experimental results verified thermal efficiency improvement and fuel savings. -- Abstract: Thermal efficiency improvement of a water heater was investigated numerically and experimentally in response to presence of a baffle, particularly designed for modifying the flow field within the water reservoir and enhancing heat transfer extracted into the water tank. A residential natural gas-fired water heater was selected for modifying its water tank through introducing a baffle for lowering natural gas consumption by 5% as a target. Based on the geometric features of the selected water heater, three-dimensional models of the water heater subsections were developed. Upon detailed studies of flow and heat transfer in each subsection, various sub-models were integrated to a complete model of the water heater. Thermal performance of the selected water heater was investigated numerically using computational fluid dynamics analysis. Prior to baffle design process and in order to verify the developed model of the water heater, time-dependent numerically-predicted temperatures were compared to the experimentally-measured temperatures under the same conditions at six (6) different locations inside the water tank and good agreement was observed. Upon verifying the numerical model, the fluid flow and heat transfer patterns were characterized for the selected water heater. The overall design of the baffle and its location and orientation were finalized based on the numerical results and a set of parametric studies. Finally, two baffle designs were proposed, with the second design being an optimized version of the first design. The

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-03-01

    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.

  12. 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.

  13. 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.

  14. Pengaruh Pelat Penyerap Ganda Model Gelombang dengan Penambahan Reflector terhadap Kinerja Solar Water Heater Sederhana

    OpenAIRE

    Ismail, Nova Risdiyanto

    2011-01-01

    Telah banyak dilakukan USAha meningkatkan kinerja solar water heater diantaranya modifikasi pelat penyerap tunggal menjadi ganda, modifikasi aliran untuk meningkatkan penyerapan panas, modifikasi material dan pelat penyerap ganda model gelombang. Penelitian ini bertujuan untuk mengetahui pengaruh pelat penyerap ganda model gelombang dengan penambahan reflector terhadap kinerja solar water heater sederhana. Dalam penelitian ini dilakukan secara eksperimen, untuk embandingkan kinerja pelat pen...

  15. 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 on the co...... for future system optimization....

  16. Optimal and Learning-Based Demand Response Mechanism for Electric Water Heater System

    Directory of Open Access Journals (Sweden)

    Bo Lin

    2017-10-01

    Full Text Available This paper investigates how to develop a learning-based demand response approach for electric water heater in a smart home that can minimize the energy cost of the water heater while meeting the comfort requirements of energy consumers. First, a learning-based, data-driven model of an electric water heater is developed by using a nonlinear autoregressive network with external input (NARX using neural network. The model is updated daily so that it can more accurately capture the actual thermal dynamic characteristics of the water heater especially in real-life conditions. Then, an optimization problem, based on the NARX water heater model, is formulated to optimize energy management of the water heater in a day-ahead, dynamic electricity price framework. A genetic algorithm is proposed in order to solve the optimization problem more efficiently. MATLAB (R2016a is used to evaluate the proposed learning-based demand response approach through a computational experiment strategy. The proposed approach is compared with conventional method for operation of an electric water heater. Cost saving and benefits of the proposed water heater energy management strategy are explored.

  17. Report of the workshop Energy Utility and Solar Water Heater 1993

    International Nuclear Information System (INIS)

    1993-01-01

    The title workshop was organized to increase the interest of energy utilities for the Solar Water Heater campaign by providing representatives of the utilities with information about the technical and marketing aspects of solar boilers, and to stimulate knowledge transfer between the energy utilities about the method, the possibilities and bottlenecks of solar water heater projects

  18. Policy development for solar water heaters: the case of Lebanon

    International Nuclear Information System (INIS)

    Chedid, R.B.

    2000-01-01

    Full text.The electric energy demand in Lebanon is estimated to grow at an average of 3-5% per year for the coming 10 years. Such an increase in energy demand is problematic for Lebanon since its economy is almost totally dependent on imported fuel which contributes to 97% of the overall energy requirements. Solar water heaters (SWH) are regarded as the most important element in a long term energy conservation and management strategy for this country, but their promotion is a national issue requiring the participation of many stake holders and decision makers. Additionally, the success of solar energy penetration into the existing energy market is constrained by many factors such as technical and financial limitations, decision criteria and policy instruments. This paper will explore the feasibility of SWH, and will work out, using the Analytic Hierarchy Process technique, a policy to ensure a large scale diffusion of SWH in the energy market

  19. Integrated collector storage solar water heater: Temperature stratification

    International Nuclear Information System (INIS)

    Garnier, C.; Currie, J.; Muneer, T.

    2009-01-01

    An analysis of the temperature stratification inside an Integrated Collector Storage Solar Water Heater (ICS-SWH) was carried out. The system takes the form of a rectangular-shaped box incorporating the solar collector and storage tank into a single unit and was optimised for simulation in Scottish weather conditions. A 3-month experimental study on the ICS-SWH was undertaken in order to provide empirical data for comparison with the computed results. Using a previously developed macro model; a number of improvements were made. The initial macro model was able to generate corresponding water bulk temperature in the collector with a given hourly incident solar radiation, ambient temperature and inlet water temperature and therefore able to predict ICS-SWH performance. The new model was able to compute the bulk water temperature variation in different SWH collectors for a given aspect ratio and the water temperature along the height of the collector (temperature stratification). Computed longitudinal temperature stratification results obtained were found to be in close agreement with the experimental data.

  20. Electrochemical corrosion protection of storage water heaters in the building services; Elektrochemischer Korrosionsschutz von Speicher-Wassererwaermern in der Gebaeudetechnik

    Energy Technology Data Exchange (ETDEWEB)

    Bytyn, Wilfried [MAGONTEC GmbH, Bottrop (Germany)

    2012-06-15

    Storage water heaters currently experience a new consideration as a central thermal energy storage with an energy buffer characteristics. The contribution under consideration presents the principles and conditions of use for the cathodic corrosion protection of storage water heaters.

  1. Numerical and experimental investigation of thermosyphon solar water heater

    International Nuclear Information System (INIS)

    Zelzouli, Khaled; Guizani, Amenallah; Kerkeni, Chakib

    2014-01-01

    Highlights: • We studied a thermosyphon solar water heater composed of high-performance components. • A differential equations solution technique is investigated. • The influences of the collector and storage losses on the system performance were examined. • The storage losses have more influence on the long-term performance. - Abstract: A glassed flat plate collector with selective black chrome coated absorber and a low wall conductance horizontal storage are combined in order to set up a high performance thermosyphon system. Each component is tested separately before testing the complete system in spring days. During the test period, effect of different inlet water temperatures on the collector performance is studied and results have shown that the collector can reach a high efficiency and high outlet water temperature even for elevated inlet water temperatures. Subsequently, long term system performance is estimated by using a developed numerical model. The proposed model, accurate and gave a good agreement with experimental results, allowed to describe the heat transfer in the storage. It has shown also that the long-term performances are strongly influenced by losses from the storage than losses from the collector

  2. Wasted Heat Engine Utilization in Central AC Condenser Type Water Chiller for Economical Energy Water Heaters

    Directory of Open Access Journals (Sweden)

    I Made Rasta

    2012-11-01

    Full Text Available Central AC type water chiller is a refrigeration machine that release heat to environment. Heat energy that released to environment comes from room heat load that absorbed by machine and heat from compressor. The best form in using this loss energy is heat recovery water heater technology, where this machine will take heat from condenser by a heat exchanger to heating water. Refrigerant will flow in the heat exchanger before entering condenser, after that refrigerant flow to other components such as, expansion valve, evaporator, compressor and than return again to condenser, this process will be cycling regularly (closed cycle. Based on experimental and analysis result especially for AC with capacity 2 Pk, and tank capacity 75 liter, with water heater recovery device obtained that: (1 Compressor power consumption decrease from 1.66 kW to 1.59kW. (2 Heat rejected from condenser and used by water heater has ratio 4.683 kJ/s and 1.59 kJ/s, with water heater efficiency is 32.2%. (3 Maximum water temperature can be reached are in range 34oC – 47.5oC in 10-150 minutes and flow rate is 0.5 – 2.5 liter /min

  3. 75 FR 21981 - Energy Conservation Program: Energy Conservation Standards for Residential Water Heaters, Direct...

    Science.gov (United States)

    2010-04-27

    ... DEPARTMENT OF ENERGY 10 CFR Part 430 [Docket Number EE-2006-BT-STD-0129] 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 on page 20112 in the issue of Friday...

  4. 76 FR 63211 - Energy Efficiency Program: Test Procedures for Residential Water Heaters, Direct Heating...

    Science.gov (United States)

    2011-10-12

    ... DEPARTMENT OF ENERGY 10 CFR Part 430 [Docket Number EERE-2011-BT-TP-0042] RIN 1904-AC53 Energy Efficiency Program: Test Procedures for Residential Water Heaters, Direct Heating Equipment, and Pool Heaters AGENCY: Office of Energy Efficiency and Renewable Energy, Department of Energy. ACTION: Request for...

  5. Solar water heaters: possibilities of using in the climatic conditions of the Russia medium area

    International Nuclear Information System (INIS)

    Popel', O.S.; Frid, S.E.

    2001-01-01

    On the basis of mathematical simulation of the simplest solar water heating facility using up-to-date software and data of typical meteorological year it was shown that under the real climatic conditions peculiar to Russia central region it is appropriate to use seasonal solar water heaters operating from March up to September. It is shown that to promote solar water heaters in the Russian market one should elaborate engineering approaches and should introduce new materials ensuring reduction of cost of solar water heaters with the availability of high quality and durability [ru

  6. Economics of residential gas furnaces and water heaters in United States new construction market

    OpenAIRE

    Lekov, Alex B.

    2009-01-01

    New single-family home construction represents a significant and important market for the introduction of energy-efficient gas-fired space heating and water-heating equipment. In the new construction market, the choice of furnace and water-heater type is primarily driven by first cost considerations and the availability of power vent and condensing water heaters. Few analysis have been performed to assess the economic impacts of the different combinations of space and water-heating equipment....

  7. Exergy Analysis of Serpentine Thermosyphon Solar Water Heater

    Directory of Open Access Journals (Sweden)

    Muhammad Faisal Hasan

    2018-03-01

    Full Text Available The performance of a solar hot water system is assessed for heat pump and domestic heating applications. Thermodynamic analysis on a serpentine-type thermosyphon flat-plate solar heater is conducted using the Second Law of thermodynamics. Exergetic optimization is first performed to determine the parameters for the maximum exergy efficiency using MATLAB optimization toolbox. Geometric parameters (collector surface area, dimensions, and pipe diameter, optical parameters (transmittance absorptance product, ambient temperature, solar irradiation and operating parameters (mass flow rate, fluid temperature, and overall heat transfer (loss coefficient are accounted for in the optimization scheme. The exergy efficiency at optimum condition is found to be 3.72%. The results are validated using experimental data and found to be in good agreement. The analysis is further extended to the influence of various operating parameters on the exergetic efficiency. It is observed that optical and thermal exergy losses contribute almost 20%, whereas approximately 77% exergy destruction is contributed by the thermal energy conversion. Exergy destruction due to pressure drop is found negligible. The result of this analysis can be used for designing and optimization of domestic heat pump system and hot water application.

  8. Management of aging of water heaters in nuclear power plants

    International Nuclear Information System (INIS)

    Martin-Serrano Ledesma, C.; Toro del toro, J.; Real Rubio, I.; Garcia Montejano, A.

    2014-01-01

    The scope of this work includes the study of all feedwater heaters (from 1 to 6) in their two trains (A and B). In this study the main degradation phenomena that affect them, the operating parameters that can warn of a possible malfunction of the heater and possible strategies inspection, repair and replacement are analyzed. As a result of this study, a higher priority is obtained at a lower state of degradation of the heaters, possibly with a strategy inspection, repair or replacement, for each recharge, until the end of life of the plant. This will be a live program, which must be fed back to the studies of the parameters of operation of the heater during operation and results of the inspection of each recharge. May verify the effectiveness of aging management program using different indicators. (Author)

  9. Integrated collector-storage solar water heater with extended storage unit

    International Nuclear Information System (INIS)

    Kumar, Rakesh; Rosen, Marc A.

    2011-01-01

    The integrated collector-storage solar water heater (ICSSWH) is one of the simplest designs of solar water heater. In ICSSWH systems the conversion of solar energy into useful heat is often simple, efficient and cost effective. To broaden the usefulness of ICSSWH systems, especially for overnight applications, numerous design modifications have been proposed and analyzed in the past. In the present investigation the storage tank of an ICSSWH is coupled with an extended storage section. The total volume of the modified ICSSWH has two sections. Section A is exposed to incoming solar radiation, while section B is insulated on all sides. An expression is developed for the natural convection flow rate in section A. The inter-related energy balances are written for each section and solved to ascertain the impact of the extended storage unit on the water temperature and the water heater efficiency. The volumes of water in the two sections are optimized to achieve a maximum water temperature at a reasonably high efficiency. The influence is investigated of inclination angle of section A on the temperature of water heater and the angle is optimized. It is determined that a volume ratio of 7/3 between sections A and B yields the maximum water temperature and efficiency in the modified solar water heater. The performance of the modified water heater is also compared with a conventional ICSSWH system under similar conditions.

  10. Applying water cooled air conditioners in residential buildings in Hong Kong

    International Nuclear Information System (INIS)

    Chen Hua; Lee, W.L.; Yik, F.W.H.

    2008-01-01

    The objective of this study is to conduct a realistic prediction of the potential energy saving for using water cooled air conditioners in residential buildings in Hong Kong. A split type air conditioner with air cooled (AAC) and water cooled (WAC) options was set up for experimental study at different indoor and outdoor conditions. The cooling output, power consumption and coefficient of performance (COP) of the two options were measured and calculated for comparison. The experimental results showed that the COP of the WAC is, on average, 17.4% higher than that of the AAC. The results were used to validate the mathematical models formulated for predicting the performance of WACs and AACs at different operating conditions and load characteristics. While the development of the mathematical models for WACs was reported in an earlier paper, this paper focuses on the experimental works for the AAC. The mathematical models were further used to predict the potential energy saving for application of WACs in residential buildings in Hong Kong. The predictions were based on actual building developments and realistic operating characteristics. The overall energy savings were estimated to be around 8.7% of the total electricity consumption for residential buildings in Hong Kong. Wider use of WACs in subtropical cities is, therefore, recommended

  11. Economics of residential gas furnaces and water heaters in United States new construction market

    Energy Technology Data Exchange (ETDEWEB)

    Lekov, Alex B.; Franco, Victor H.; Wong-Parodi, Gabrielle; McMahon, James E.; Chan, Peter

    2009-05-06

    New single-family home construction represents a significant and important market for the introduction of energy-efficient gas-fired space heating and water-heating equipment. In the new construction market, the choice of furnace and water-heater type is primarily driven by first cost considerations and the availability of power vent and condensing water heaters. Few analysis have been performed to assess the economic impacts of the different combinations of space and water-heating equipment. Thus, equipment is often installed without taking into consideration the potential economic and energy savings of installing space and water-heating equipment combinations. In this study, we use a life-cycle cost analysis that accounts for uncertainty and variability of the analysis inputs to assess the economic benefits of gas furnace and water-heater design combinations. This study accounts not only for the equipment cost but also for the cost of installing, maintaining, repairing, and operating the equipment over its lifetime. Overall, this study, which is focused on US single-family new construction households that install gas furnaces and storage water heaters, finds that installing a condensing or power-vent water heater together with condensing furnace is the most cost-effective option for the majority of these houses. Furthermore, the findings suggest that the new construction residential market could be a target market for the large-scale introduction of a combination of condensing or power-vent water heaters with condensing furnaces.

  12. EFFICIENCY OF THE CAPACITY-TYPE SOLAR WATER HEATER WITH THE FLEXIBLE POLYMER ABSORBER.

    Directory of Open Access Journals (Sweden)

    Ermuratschii V.V.

    2008-08-01

    Full Text Available Energetic indexes of solar capacity-type water heaters with flexible polymer absorbers and different constructions of enclosures using the refined method of calculus were obtained.

  13. 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.

  14. 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.

  15. 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

    ... efficiency of commercial water heaters and hot water supply boilers (other than commercial heat pump water... PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Commercial Water Heaters, Hot Water Supply Boilers and Unfired Hot Water Storage Tanks Test Procedures § 431.106 Uniform test method for the measurement...

  16. Energy consumption modeling of air source electric heat pump water heaters

    International Nuclear Information System (INIS)

    Bourke, Grant; Bansal, Pradeep

    2010-01-01

    Electric heat pump air source water heaters may provide an opportunity for significant improvements in residential water heater energy efficiency in countries with temperate climates. As the performance of these appliances can vary widely, it is important for consumers to be able to accurately assess product performance in their application to maximise energy savings and ensure uptake of this technology. For a given ambient temperature and humidity, the performance of an air source heat pump water heater is strongly correlated to the water temperature in or surrounding the condenser. It is therefore important that energy consumption models for these products duplicate the real-world water temperatures applied to the heat pump condenser. This paper examines a recently published joint Australian and New Zealand Standard, AS/NZS 4234: 2008; Heated water systems - Calculation of energy consumption. Using this standard a series TRNSYS models were run for several split type air source electric heat pump water heaters. An equivalent set of models was then run utilizing an alternative water use pattern. Unfavorable errors of up to 12% were shown to occur in modeling of heat pump water heater performance using the current standard compared to the alternative regime. The difference in performance of a model using varying water use regimes can be greater than the performance difference between models of product.

  17. Research and development of an air-cycle heat-pump water heater. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Dieckmann, J.T.; Erickson, A.J.; Harvey, A.C.; Toscano, W.M.

    1979-10-01

    A prototype reverse Brayton air cycle heat pump water heater has been designed and built for residential applications. The system consists of a compressor/expander, an air-water heat exchanger, an electric motor, a water circulation pump, a thermostat, and fluid management controls. The prototype development program consisted of a market analysis, design study, and development testing. A potential residential market for the new high-efficiency water heater of approximately 480,000 units/y was identified. The retail and installation cost of this water heater is estimated to be between $500 and $600 which is approximately $300 more than a conventional electric water heater. The average payback per unit is less than 3-1/2 y and the average recurring energy cost savings after the payback period is approximately $105/y at the average seasonal coefficient of performance (COP) of 1.7. As part of the design effort, a thermodynamic parametric analysis was performed on the water heater system. It was determined that to obtain a coefficient of performance of 1.7, the isentropic efficiency of both the compressor and the expander must be at least 85%. The selected mechanical configuration is described. The water heater has a diameter of 25 in. and a height of 73 in. The results of the development testing of the prototype water heater system showed: the electrical motor maximum efficiency of 78%; the compressor isentropic efficiency is 95 to 119% and the volumetric efficiency is approximately 85%; the expander isentropic efficiency is approximately 58% and the volumetric efficiency is 92%; a significant heat transfer loss of approximately 16% occurred in the expander; and the prototype heat pump system COP is 1.26 which is less than the design goal of at least 1.7. Future development work is recommended.

  18. Study on the selection method of feed water heater safety valves in nuclear power plants

    International Nuclear Information System (INIS)

    Shi Jianzhong; Huang Chao; Hu Youqing

    2014-01-01

    The selection of the high pressure feedwater heater's safety valve usually follows the principle recommended by HEI standards in thermal power plant. However, the nuclear power plant's heaters generally need to accept a lots of drain from a moisture separator reheater (MSR). When the drain regulating valve was failure in fully open position, a large number of high pressure steam will directly goes into the heater. It make high-pressure heater have a risk of overpressure. Therefore, the safety valve selection of the heaters for nuclear power plants not only need to follow the HEI standards, but also need to check his capacity in certain special conditions. The paper established a calculation method to determine the static running point of the heaters based on characteristic equations of the feed water heater, drain regulating valve and steam extraction pipings, and energy balance principle. The method can be used to calculate the equilibrium pressure of various special running conditions, so further determine whether the capacity of the safety valve meets the requirements of safety and emissions. The method proposed in this paper not only can be used for nuclear power plants, can also be used for thermal power plants. (authors)

  19. The use of helical heat exchanger for heat recovery domestic water-cooled air-conditioners

    International Nuclear Information System (INIS)

    Yi Xiaowen; Lee, W.L.

    2009-01-01

    An experimental study on the performance of a domestic water-cooled air-conditioner (WAC) using tube-in-tube helical heat exchanger for preheating of domestic hot water was carried out. The main aims are to identify the comprehensive energy performance (space cooling and hot water preheating) of the WAC and the optimum design of the helical heat exchanger taking into account the variation in tap water flow rate. A split-type WAC was set up for experimental study at different indoor and outdoor conditions. The cooling output, the amount of recovered heat, and the power consumption for different hot water flow rates were measured. The experimental results showed that the cooling coefficient of performance (COP) of the WAC improves with the inclusion of the heat recovery option by a minimum of 12.3%. This can be further improved to 20.6% by an increase in tap water flow rate. Same result was observed for the comprehensive COP of the WAC. The maximum achievable comprehensive COP was 4.92 when the tap water flow rate was set at 7.7 L/min. The overall heat transfer coefficient of the helical heat exchanger under various operating conditions were determined by Wilson plot. A mathematical model relating the over all heat transfer coefficient to the outer pipe diameter was established which provides a convenient way of optimising the design of the helical heat exchanger

  20. Nocturnal reverse flow in water-in-glass evacuated tube solar water heaters

    International Nuclear Information System (INIS)

    Tang, Runsheng; Yang, Yuqin

    2014-01-01

    Highlights: • Performance of water-in-glass evacuated tube solar water heaters (SWH) at night was studied. • Experimental measurements showed that reverse flow occurred in SWHs at night. • Reverse flow in SWHs was very high but the heat loss due to reverse flow was very low. • Reverse flow seemed not sensitive to atmospheric clearness but sensitive to collector tilt-angle. - Abstract: In this work, the thermal performance of water-in-glass evacuated tube solar water heaters (SWH) at nights was experimentally investigated. Measurements at nights showed that the water temperature in solar tubes was always lower than that in the water tank but higher than the ambient air temperature and T exp , the temperature of water inside tubes predicted in the case of the water in tubes being naturally cooled without reverse flow. This signified that the reverse flow in the system occurred at nights, making the water in solar tubes higher than T exp . It is found that the reverse flow rate in the SWH, estimated based on temperature measurements of water in solar tubes, seemed not sensitive to the atmospheric clearness but sensitive to the collector tilt-angle, the larger the tilt-angle of the collector, the higher the reverse flow rate. Experimental results also showed that, the reverse flow in the SWH was much higher as compared to that in a thermosyphonic domestic solar water heater with flat-plate collectors, but the heat loss from collectors to the air due to reverse flow in SWHs was very small and only took about 8–10% of total heat loss of systems

  1. Dissemination of Solar Water Heaters in Taiwan: The Case of Remote Islands

    Directory of Open Access Journals (Sweden)

    Kung-Ming Chung

    2013-10-01

    Full Text Available Solar water heaters represent the success story in the development of renewable energy in Taiwan. With increasing public awareness, there are over 0.3 million residential systems in operation. To disseminate solar water heaters in remote islands, economic feasibility and water quality are taken into account in this study. The payback period in Kinmen and Penghu Counties are evaluated, according to effective annual solar energy gain, hot water consumption pattern and cost. Assessment of the scaling and corrosion tendencies for solar water heaters using tap and underground water are also presented. For flat-plate solar collectors with metal components, favorable corrosion resistance and protective anti-corrosion coatings are required.

  2. Method and apparatus for enhanced heat recovery from steam generators and water heaters

    Science.gov (United States)

    Knight, Richard A.; Rabovitser, Iosif K.; Wang, Dexin

    2006-06-27

    A heating system having a steam generator or water heater, at least one economizer, at least one condenser and at least one oxidant heater arranged in a manner so as to reduce the temperature and humidity of the exhaust gas (flue gas) stream and recover a major portion of the associated sensible and latent heat. The recovered heat is returned to the steam generator or water heater so as to increase the quantity of steam generated or water heated per quantity of fuel consumed. In addition, a portion of the water vapor produced by combustion of fuel is reclaimed for use as feed water, thereby reducing the make-up water requirement for the system.

  3. Understanding the Ecological Adoption of Solar Water Heaters Among Customers of Island Economies

    Directory of Open Access Journals (Sweden)

    Pudaruth Sharmila

    2017-04-01

    Full Text Available This paper explores the major factors impacting upon the ecological adoption of solar water heaters in Mauritius. The paper applies data reduction technique by using exploratory factor analysis on a sample of 228 respondents and condenses a set of 32 attributes into a list of 8 comprehensible factors impacting upon the sustained adoption of solar water heater in Mauritius. Multiple regression analysis was also conducted to investigate upon the most predictive factor influencing the adoption of solar water heaters in Mauritius. The empirical estimates of the regression analysis have also depicted that the most determining factor pertaining to the ‘government incentives for solar water heaters’ impacts upon the adoption of solar water heaters. These results can be related to sustainable adoption of green energy whereby targeted incentive mechanisms can be formulated with the aim to accelerate and cascade solar energy adoption in emerging economies. A novel conceptual model was also proposed in this paper, whereby, ecological stakeholders in the sustainable arena could use the model as a reference to pave the way to encourage adoption of solar water heating energy. This research represents a different way of understanding ecological customers by developing an expanding on an original scale development for the survey on the ecological adoption of solar water heaters.

  4. An investigation of the Performance of a Conical Solar Water Heater in the Kingdom of Bahrain

    Science.gov (United States)

    Gaaliche, Nessreen; Ayhan, Teoman; Fathallah, Raouf

    2017-11-01

    Domestic water heater corresponds to 25% of the house energy consumption and can play an important role to reduce energy house expenses. Solar energy offers a preferred renewable energy resource because of its economic and environmental advantages. It is considered the best alternative to reduce domestic water heater energy consumption cost. Converting solar energy into heat can be considered among the simplest used systems. Solar thermal conversion is more efficient than solar electrical direct conversion method. Solar water heater systems are particularly easy to use and to repair. The integrated conical solar collector water heater (ICSCWH) is so far the easiest among water heating systems. The ICSCWH converts directly and efficiently the solar flux into heat. In order to expand the utilization of ICSCWH systems, many design modifications have been examined and analyzed. This study provides an experimental investigation and mathematical simulation of an ICSCWH system equipped with a glass cover resulting in the increase of the maximum absorption. Integrating the cone-shaped heat collector with an aluminum spiral pipe flow system may enhance the efficiency of the proposed system. In order to maximize the solar radiation of the system, the solar water heater has been designed in a conical shape, which removes the need to change its orientation toward the sun to receive the maximum sun radiation during the day. In this system, the heating of water has been obtained using the spiral pipe flow without the use of the solar cells and mirrors in order to reduce the total cost. The storage water tank of this system is coupled with a conical solar collector. Based on the above design, the solar water heater has been fabricated and tested. In addition, an analytical modeling approach aiming to predict the flow rate within the conical integrated collector storage solar water heater (ICSSWH) and its efficiency, was developed. Modeling through a numerical simulation approach

  5. An investigation of the Performance of a Conical Solar Water Heater in the Kingdom of Bahrain

    Directory of Open Access Journals (Sweden)

    Gaaliche Nessreen

    2017-01-01

    Full Text Available Domestic water heater corresponds to 25% of the house energy consumption and can play an important role to reduce energy house expenses. Solar energy offers a preferred renewable energy resource because of its economic and environmental advantages. It is considered the best alternative to reduce domestic water heater energy consumption cost. Converting solar energy into heat can be considered among the simplest used systems. Solar thermal conversion is more efficient than solar electrical direct conversion method. Solar water heater systems are particularly easy to use and to repair. The integrated conical solar collector water heater (ICSCWH is so far the easiest among water heating systems. The ICSCWH converts directly and efficiently the solar flux into heat. In order to expand the utilization of ICSCWH systems, many design modifications have been examined and analyzed. This study provides an experimental investigation and mathematical simulation of an ICSCWH system equipped with a glass cover resulting in the increase of the maximum absorption. Integrating the cone-shaped heat collector with an aluminum spiral pipe flow system may enhance the efficiency of the proposed system. In order to maximize the solar radiation of the system, the solar water heater has been designed in a conical shape, which removes the need to change its orientation toward the sun to receive the maximum sun radiation during the day. In this system, the heating of water has been obtained using the spiral pipe flow without the use of the solar cells and mirrors in order to reduce the total cost. The storage water tank of this system is coupled with a conical solar collector. Based on the above design, the solar water heater has been fabricated and tested. In addition, an analytical modeling approach aiming to predict the flow rate within the conical integrated collector storage solar water heater (ICSSWH and its efficiency, was developed. Modeling through a numerical

  6. Building America Case Study: Assessment of a Hybrid Retrofit Gas Water Heater

    Energy Technology Data Exchange (ETDEWEB)

    M. Hoeschele, E. Weitzel, C. Backman

    2017-06-01

    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 half-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.

  7. Integrated solar water-heater and solar water cooler performance during winter time

    International Nuclear Information System (INIS)

    Shaikh, N.U.; Siddiqui, M.A

    2012-01-01

    Solar powered water heater and water cooler is an important contribution for the reduction of fossil fuel consumptions and harmful emissions to the environment. This study aims to harness the available solar potential of Pakistan and provide an option fulfilling the domestic hot and cold water demands during winter and summer seasons respectively. The system was designed for the tap-water temperature of 65 degree C (149 degree F) and the chilled drinking-water temperature of 14 degree C (57 degree F) that are the recommended temperatures by World Health Organization (WHO). The solar water heater serves one of the facilities of the Department of Mechanical Engineering at NED University of Engineering and Technology whereas, the solar water cooler will provide drinking water to approximately 50 people including both faculty and students. A pair of single glazed flat plate solar collector was installed to convert solar radiations to heat. Hot water storage and supply system was carefully designed and fabricated to obtain the designed tap-water temperature. Vapour-absorption refrigeration system was designed to chill drinking water. Intensity of solar radiations falling on the solar collector, water temperatures at the inlet and outlet of the solar collectors and the tap water temperature were measured and analyzed at different hours of the day and at different days of the month. The results show that the installed solar collector system has potential to feed hot water of temperatures ranging from 65 degree C (149 degree F) to 70 Degree C (158 degree F), that is the required hot water temperature to operate a vapour absorption chilled water production system. (author)

  8. Estimation of cobalt release from feed water heater tubes of BWRs

    International Nuclear Information System (INIS)

    Uchida, S.; Kitamura, M.; Ozawa, Y.

    1983-01-01

    To evaluate the release source of cobalt from heater tubes of the feed water line, release rate measurements were carried out by detecting 60 Co released from irradiated stainless steel in contact with neutral water at an oxygen concentration of 20 ppb. The dependences of cobalt release rate on temperature, flow velocity and exposure time were studied after 670 hours of release experiments, and an empirical equation (which is presented) was obtained in the temperature range from 150 to 240 deg C. A decrease in the cobalt release rate above 250 deg C was considered due to the formation of a protective oxide layer. From these data, the amount of cobalt released from individual feed water heaters was evaluated. It was demonstrated that low cobalt containing stainless steel was economically applied only in the higher temperature region of the heater (20% of the total surface) to reduce cobalt feed rate into the reactor (to approx. 1/2). (author)

  9. 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 of...

  10. 75 FR 52892 - Energy Conservation Program for Consumer Products: Test Procedures for Residential Water Heaters...

    Science.gov (United States)

    2010-08-30

    ... ``Energy Conservation Program for Consumer Products Other Than Automobiles,'' including residential water... final rule revising energy conservation standards for residential water heaters, direct heating.... EERE-2009-BT-TP-0013] RIN 1904-AB95 Energy Conservation Program for Consumer Products: Test Procedures...

  11. One-year assessment of a solar space/water heater--Clinton, Mississippi

    Science.gov (United States)

    1981-01-01

    Unit called "System 4" integrated into space-heating and hot-water systems of dormitory satisfied 32 percent of building heat load. System 4 includes flat-plate air collectors, circulation blowers, rock storage bed with heat exchanger, two hot water tanks, and auxiliary heaters. Report describes performance of system and subsystems, operating-energy requirements and savings, and performance parameters.

  12. 16 CFR Appendix D2 to Part 305 - Water Heaters-Electric

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Water Heaters-Electric D2 Appendix D2 to... PRODUCTS REQUIRED UNDER THE ENERGY POLICY AND CONSERVATION ACT (âAPPLIANCE LABELING RULEâ) Pt. 305, App. D2 Appendix D2 to Part 305—Water Heaters—Electric Range Information CAPACITY FIRST HOUR RATING Range of...

  13. 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

  14. 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.

  15. Building America Case Study: Assessment of a Hybrid Retrofit Gas Water Heater

    Energy Technology Data Exchange (ETDEWEB)

    2017-06-19

    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 half-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. 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

  17. Pretest thermal analysis of the Tuff Water Migration/In-Situ Heater Experiment

    International Nuclear Information System (INIS)

    Bulmer, B.M.

    1980-02-01

    This report describes the pretest thermal analysis for the Tuff Water Migration/In-Situ Heater Experiment to be conducted in welded tuff in G-tunnel, Nevada Test Site. The parametric thermal modeling considers variable boiling temperature, tuff thermal conductivity, tuff emissivity, and heater operating power. For nominal tuff properties, some near field boiling is predicted for realistic operating power. However, the extent of boiling will be strongly determined by the ambient (100% water saturated) rock thermal conductivity. In addition, the thermal response of the heater and of the tuff within the dry-out zone (i.e., bounded by boiling isotherm) is dependent on the temperature variation of rock conductivity as well as the extent of induced boiling

  18. 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.

  19. 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.

  20. Economics of Condensing Gas Furnaces and Water Heaters Potential in Residential Single Family Homes

    OpenAIRE

    Lekov, Alex

    2010-01-01

    Residential space and water heating accounts for over 90percent of total residential primary gas consumption in the United States. Condensing space and water heating equipment are 10-30percent more energy-efficient than conventional space and water heating. Currently, condensing gas furnaces represent 40 percent of shipments and are common in the Northern U.S. market. Meanwhile, manufacturers are planning to develop condensing gas storage water heaters to qualify for Energy Star? certificati...

  1. Studi Kinerja Solar Water Heater Dengan Aliran Zig-zag Beralur Balok

    OpenAIRE

    Ikhsan, M. Rizki; Soeparman, Sudjito; Sasongko, Mega Nur

    2017-01-01

    Solar energy can be used for water heating by using solar water heater application. Therefore, its still needs some modification due to its low efficiency. This modification can be done by replacing the conventional plate of solar collectors into a double plate with a zig-zag pattern. The results shown that along with the decreasing of water flow rates could significantly increase the useful energy (Qu). Initial temperature of water inlet could affect the generated maximum temperature. The hi...

  2. Summer Indoor Heat Pump Water Heater Evaluation in a Hot-Dry Climate

    Energy Technology Data Exchange (ETDEWEB)

    Hoeschele, Marc [National Renewable Energy Lab. (NREL), Golden, CO (United States); Seitzler, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-05-01

    Heat pump water heaters offer a significant opportunity to improve water heating performance for the over 40% of U.S. households that heat domestic hot water using electric resistance storage water heaters. Numerous field studies have also been completed documenting performance in a variety of climates and applications. More recent evaluation efforts have focused attention on the performance of May through September 2014, with ongoing winter monitoring being sponsored by California utility partners. Summer results show favorable system performance with extrapolated annual water heating savings of 1,466 to 2,300 kWh per year, based on the observed hot water loads. Additional summer space cooling benefits savings of 121 to 135 kWh per year were projected, further increasing the water energy savings.

  3. Environmental aspects of the use of materials for solar water heaters

    International Nuclear Information System (INIS)

    Van der Leun, C.J.; De Jager, D.

    1994-10-01

    The study on the title subject has been carried out in order to apply the results in new designs and to improve the production of solar water heating systems. Attention is paid to solar water heaters that are under development and solar water heaters that are commercially available in the Netherlands. Use has been made of a IVAM-developed product analysis method. For seven solar water heater concepts, that were on the market or under development in the Netherlands in 1992, the applied amounts of materials have been inventorized. Data on the environmental effects of the production of these materials are outlined and aggregated on the level of the components and the systems. Based on those data, environmental profiles are drafted, comprising 'effect scores' on 9 environmental criteria. However, the environmental 'effect scores' are not reliable enough to determine the most important factors in order to identify options to reduce the negative environmental effects. Data on the energy consumption of the production of relevant materials are available and reliable. The solar water heaters, considered in this report, do not show large differences for that matter. It appears that the amounts of air pollution, water pollution and waste flow from the production of materials for solar water heaters are no reasons to further reduce environmental effects of the production. It is recommended to focus on the reduction of material quantities and to increase the quantity of recycled material. Also it is recommended that manufacturers of solar boilers set up a take-back system. 43 tabs., 1 appendix, 56 refs

  4. Acceptability of the integral solar water heater by householders in the low income urban community

    CSIR Research Space (South Africa)

    Basson, FA

    1984-01-01

    Full Text Available A research and demonstration project on the use and performance of low cost integral solar water heaters in urban low-income dwellings was carried out in 1982/83. The project involved technical and socio-economic components. This report summarises...

  5. A figure of merit for selective absorbers in flat plate solar water heaters

    CSIR Research Space (South Africa)

    Roberts, DE

    2013-12-01

    Full Text Available We derive from first principles an analytical expression for a figure of merit (FM) for a selective solar absorber in a single glazed flat plate water heater. We first show that the efficiency of a collector with an absorber with absorptance α...

  6. 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

  7. NORTH PORTAL-WATER HEATER CALCULATION-SHOP BUILDING No. 5006

    International Nuclear Information System (INIS)

    R. Blackstone

    1996-01-01

    The purpose of this design analysis and calculation is to determine the demand for hot and the selection of a water heater of appropriate size, in accordance with the Uniform Plumbing Code (Section 4.4.1) and U.S. Department of Energy Order 6430.1A-1540 (Section 4.4.2)

  8. Radiative heat transfer analysis in pure water heater used for semiconductor processing

    International Nuclear Information System (INIS)

    Liu, L.H.; Kudo, K.; Mochida, A.; Ogawa, T.; Kadotani, K.

    2004-01-01

    A simplified one-dimensional model is presented to analyze the non-gray radiative transfer in pure water heater used in the rinsing processes within semiconductor production lines, and the ray-tracing method is extended to simulate the radiative heat transfer. To examine the accuracy of the simplified model, the distribution of radiation absorption is determined by the ray-tracing method based the simplified model and compared with the data obtained by three-dimensional non-gray model in combination with Monte Carlo method in reference, and the effects of the water thickness on the radiation absorption are analyzed. The results show that the simplified model has a good accuracy in solving the radiation absorption in the pure water heater. The radiation absorption increases with the water thickness, but when the water thickness is greater than 50 mm, the radiation absorption increases very slowly with the water thickness

  9. 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.

  10. 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.

  11. Impacts of soil conditioners and water table management on phosphorus loss in tile drainage from a clay loam soil.

    Science.gov (United States)

    Zhang, T Q; Tan, C S; Zheng, Z M; Welacky, T W; Reynolds, W D

    2015-03-01

    Adoption of waste-derived soil conditioners and refined water management can improve soil physical quality and crop productivity of fine-textured soils. However, the impacts of these practices on water quality must be assessed to ensure environmental sustainability. We conducted a study to determine phosphorus (P) loss in tile drainage as affected by two types of soil conditioners (yard waste compost and swine manure compost) and water table management (free drainage and controlled drainage with subirrigation) in a clay loam soil under corn-soybean rotation in a 4-yr period from 1999 to 2003. Tile drainage flows were monitored and sampled on a year-round continuous basis using on-site auto-sampling systems. Water samples were analyzed for dissolved reactive P (DRP), particulate P (PP), and total P (TP). Substantially greater concentrations and losses of DRP, PP, and TP occurred with swine manure compost than with control and yard waste compost regardless of water table management. Compared with free drainage, controlled drainage with subirrigation was an effective way to reduce annual and cumulative losses of DRP, PP, and TP in tile drainage through reductions in flow volume and P concentration with control and yard waste compost but not with swine manure compost. Both DRP and TP concentrations in tile drainage were well above the water quality guideline for P, affirming that subsurface loss of P from fine-textured soils can be one critical source for freshwater eutrophication. Swine manure compost applied as a soil conditioner must be optimized by taking water quality impacts into consideration. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  12. Consumers and experts. An econometric analysis of the demand for water heaters

    International Nuclear Information System (INIS)

    Van Soest, A.; Bartels, R.; Fiebig, D.G.

    2003-01-01

    Consumers can accumulate product information on the basis of a combination of searching, product advertising and expert advice. Examples of experts who provide product information include doctors advising patients on treatments, motor mechanics diagnosing car problems and recommending repairs, accountants recommending investment strategies, and plumbers making recommendations on alternative water heaters. In each of these examples, the transactions involve the sale of goods and services where the seller is at the same time an expert providing advice on the amount and type of product or service to be purchased. In the case of water heaters, the plumber advising a consumer on their choice of water heater will most likely also install the appliance. Because of the information asymmetry there is potentially a strategic element in the transmission of information from expert to consumer. This paper reports on an econometric investigation of the factors that determine the choices made by consumers and the recommendations made by plumbers and the extent to which plumbers act in the best interests of their customers. The empirical work is made possible by the availability of stated preference data generated by designed experiments involving separate samples of Australian consumers and plumbers. We find some evidence that plumbers have higher preferences than consumers for heater characteristics that increase their profit margin

  13. Studi Kinerja Solar Water Heater Dengan Aliran Zig-zag Beralur Balok

    Directory of Open Access Journals (Sweden)

    M. Rizki Ikhsan

    2017-05-01

    Full Text Available Solar energy can be used for water heating by using solar water heater application. Therefore, its still needs some modification due to its low efficiency. This modification can be done by replacing the conventional plate of solar collectors into a double plate with a zig-zag pattern. The results shown that along with the decreasing of water flow rates could significantly increase the useful energy (Qu. Initial temperature of water inlet could affect the generated maximum temperature. The highest mean efficiencies of double plate solar water heater with a zig-zag grooved beams pattern of 49.11% was gained in the flow rate of 700 mL / min.

  14. DEVELOPMENT AND PRELIMINARY TESTING OF A PARABOLIC TROUGH SOLAR WATER HEATER

    Directory of Open Access Journals (Sweden)

    O. A. Lasode

    2011-06-01

    Full Text Available Solar energy is a high-temperature, high-energy radiant energy source, with tremendous advantages over other alternative energy sources. It is a reliable, robust renewable resource which is largely undeveloped. The design and fabrication of parabolic trough solar water heater for water heating was executed. The procedure employed includes the design, construction and testing stages. The equipment which is made up of the reflector surface (curved mirror, reflector support, absorber pipe and a stand was fabricated using locally sourced materials. The results obtained. compared favourably with other research works in the literature. It depicts that employing a suitable design, selection of time of heating and proper focusing of the reflected rays to the focal spot region, solar radiation can efficiently be utilized for water heating in a tropical environment. This work presents a parabolic trough solar water heater as a suitable renewable energy technology for reducing water-heating costs.

  15. 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.

  16. EXPERIMENTAL INVESTIGATION ON THE PERFORMANCE OF THERMOSYPHON SOLAR WATER HEATER IN THE SOUTH CASPIAN SEA

    Directory of Open Access Journals (Sweden)

    Abdollah Riahi

    2011-01-01

    Full Text Available In the present study, a natural circulation closed thermosyphon flat plate solar water heater has been tested at the Faculty of Engineering of University of Mazandaran located in Babol city (36N, 52E. Data were collected for several sunny and cloudy days. Dynamic response of the system to variations in solar insolation was studied and analyzed. It was found that such systems can provide ample energy to satisfy the demand for hot water, contrary to misperception among locals

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

    OpenAIRE

    arunachala umesh chandavar

    2011-01-01

    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 o...

  18. Temperature distributions in trapezoidal built in storage solar water heaters with/without phase change materials

    International Nuclear Information System (INIS)

    Tarhan, Sefa; Sari, Ahmet; Yardim, M. Hakan

    2006-01-01

    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

  19. 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

  20. Survey of large-scale solar water heaters installed in Taiwan, China

    Energy Technology Data Exchange (ETDEWEB)

    Chang Keh-Chin; Lee Tsong-Sheng; Chung Kung-Ming [Cheng Kung Univ., Tainan (China); Lien Ya-Feng; Lee Chine-An [Cheng Kung Univ. Research and Development Foundation, Tainan (China)

    2008-07-01

    Almost all the solar collectors installed in Taiwan, China were used for production of hot water for homeowners (residential systems), in which the area of solar collectors is less than 10 square meters. From 2001 to 2006, there were only 39 large-scale systems (defined as the area of solar collectors being over 100 m{sup 2}) installed. Their utilization purposes are for rooming house (dormitory), swimming pool, restaurant, and manufacturing process. A comprehensive survey of those large-scale solar water heaters was conducted in 2006. The objectives of the survey were to asses the systems' performance and to have the feedback from the individual users. It is found that lack of experience in system design and maintenance are the key factors for reliable operation of a system. For further promotion of large-scale solar water heaters in Taiwan, a more compressive program on a system design for manufacturing process should be conducted. (orig.)

  1. 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

    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...... 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...... 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....

  2. 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.

  3. A high turndown, ultra low emission low swirl burner for natural gas, on-demand water heaters

    Energy Technology Data Exchange (ETDEWEB)

    Rapp, Vi H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Cheng, Robert K. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Therkelsen, Peter L. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2017-06-13

    Previous research has shown that on-demand water heaters are, on average, approximately 37% more efficient than storage water heaters. However, approximately 98% of water heaters in the U.S. use storage water heaters while the remaining 2% are on-demand. A major market barrier to deployment of on-demand water heaters is their high retail cost, which is due in part to their reliance on multi-stage burner banks that require complex electronic controls. This project aims to research and develop a cost-effective, efficient, ultra-low emission burner for next generation natural gas on-demand water heaters in residential and commercial buildings. To meet these requirements, researchers at the Lawrence Berkeley National Laboratory (LBNL) are adapting and testing the low-swirl burner (LSB) technology for commercially available on-demand water heaters. In this report, a low-swirl burner is researched, developed, and evaluated to meet targeted on-demand water heater performance metrics. Performance metrics for a new LSB design are identified by characterizing performance of current on-demand water heaters using published literature and technical specifications, and through experimental evaluations that measure fuel consumption and emissions output over a range of operating conditions. Next, target metrics and design criteria for the LSB are used to create six 3D printed prototypes for preliminary investigations. Prototype designs that proved the most promising were fabricated out of metal and tested further to evaluate the LSB’s full performance potential. After conducting a full performance evaluation on two designs, we found that one LSB design is capable of meeting or exceeding almost all the target performance metrics for on-demand water heaters. Specifically, this LSB demonstrated flame stability when operating from 4.07 kBTU/hr up to 204 kBTU/hr (50:1 turndown), compliance with SCAQMD Rule 1146.2 (14 ng/J or 20 ppm NOX @ 3% O2), and lower CO emissions than state

  4. Air source heat pump water heater: Dynamic modeling, optimal energy management and mini-tubes condensers

    International Nuclear Information System (INIS)

    Ibrahim, Oussama; Fardoun, Farouk; Younes, Rafic; Louahlia-Gualous, Hasna

    2014-01-01

    This paper presents a dynamic simulation model to predict the performance of an ASHPWH (air source heat pump water heater). The developed model is used to assess its performance in the Lebanese context. It is shown that for the four Lebanese climatic zones, the expected monthly values of the average COP (coefficient of performance) varies from 2.9 to 5, leading to high efficiencies compared with conventional electric water heaters. The energy savings and GHG (greenhouse gas) emissions reduction are investigated for each zone. Furthermore, it is recommended to use the ASHPWH during the period of highest daily ambient temperatures (noon or afternoon), assuming that the electricity tariff and hot water loads are constant. In addition, an optimal management model for the ASHPWH is developed and applied for a typical winter day of Beirut. Moreover, the developed dynamic model of ASHPWH is used to compare the performance of three similar systems that differ only with the condenser geometry, where results show that using mini-condenser geometries increase the COP (coefficient of performance) and consequently, more energy is saved as well as more GHG emissions are reduced. In addition, the condenser “surface compactness” is increased giving rise to an efficient compact heat exchanger. - Highlights: • Numerical modeling and experimental validation for ASHPWH (air source heat pump water heater). • Optimization of the ASHPWH-condenser length. • Comparison of the ASHPWH with conventional electric water heater according to energy efficiency and green gas house emissions. • Development of an energetic-economic optimal management model for ASHPWH. • Energetic and environmental assessment of ASHPWH with mini-tubes condensers

  5. Performance comparison of air-source heat pump water heater with different expansion devices

    International Nuclear Information System (INIS)

    Peng, Jing-Wei; Li, Hui; Zhang, Chun-Lu

    2016-01-01

    Highlights: • An air-source heat pump water heater model was developed and validated. • System performance with EEV, capillary tube or short tube orifice were compared. • Short tube orifice is more suitable for heat pump water heater than capillary tube. - Abstract: Air source heat pump water heater (ASHPWH) is designed to work under wide operating conditions. Therefore, both the system and components require higher reliability and stability than ordinary heat pump air-conditioning systems. In this paper, a quasi-steady-state system model of ASHPWH using electronic expansion valve (EEV), capillary tube or short tube orifice as expansion device is developed and validated by a prototype using R134a and scroll compressor, by which the system performance is evaluated and compared at varying water temperature and different ambient temperature. Flow characteristics of those three expansion devices in ASHPWH are comparatively analyzed. Results show that the EEV throttling system performs best. Compared with capillary tube, flow characteristics of short tube orifice are closer to that of EEV and therefore more suitable for ASHPWH. Reliability concern of liquid carryover to the compressor in the system using short tube orifice is investigated as well. Higher superheat or less system refrigerant charge could help mitigate the risk.

  6. 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.

  7. Assessment of the environmental impacts deriving from the life cycle of a typical solar water heater

    Directory of Open Access Journals (Sweden)

    G. Gaidajis

    2014-01-01

    Full Text Available According to life cycle thinking, the environmental burden deriving from different life cycle stages of a product or a system, such as manufacturing, transportation, maintenance and landfilling should be taken into consideration while assessing its environmental performance. In that aspect, the environmental impacts deriving from the life cycle of a typical solar water heater (SWH in Greece are analyzed and assessed with the application of relative life cycle assessment (LCA software in this study. In order to examine various impact categories such as global warming, ozone layer depletion, ecotoxicity and so forth, the IMPACT2002+ method is applied. The aim of this study is to examine the life cycle stages, processes and materials that significantly affect the system under examination and to provide a discussion regarding the environmental friendliness of solar water heaters.

  8. Performance of commercially available solar and heat pump water heaters

    International Nuclear Information System (INIS)

    Lloyd, C.R.; Kerr, A.S.D.

    2008-01-01

    Many countries are using policy incentives to encourage the adoption of energy-efficient hot water heating as a means of reducing greenhouse gas emissions. Such policies rely heavily on assumed performance factors for such systems. In-situ performance data for solar and heat pump hot water systems, however, are not copious in the literature. Otago University has been testing some systems available in New Zealand for a number of years. The results obtained are compared to international studies of in-situ performance of solar hot water systems and heat pump hot water systems, by converting the results from the international studies into a single index suitable for both solar and heat pump systems (COP). Variability in the international data is investigated as well as comparisons to model results. The conclusions suggest that there is not too much difference in performance between solar systems that have a permanently connected electric boost backup and heat pump systems over a wide range of environmental temperatures. The energy payback time was also calculated for electric boost solar flat plate systems as a function of both COP and hot water usage for a given value of embodied energy. The calculations generally bode well for solar systems but ensuring adequate system performance is paramount. In addition, such systems generally favour high usage rates to obtain good energy payback times

  9. 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...... gas emissions, NAMAs embody the principle of common but differentiated responsibilities. In addition to developed countries’ commitments to make quantitative reductions of greenhouse gas emissions, developing countries are invited to contribute with voluntary actions that are ‘nationally appropriate...

  10. Thermal analysis of building roof assisted with water heater and ...

    Indian Academy of Sciences (India)

    D Prakash

    2018-03-14

    Mar 14, 2018 ... Thermal analysis; building roof; solar water heating system; roof ... These solar collec- ... several benefits, such as its wide range of storage temper- ... rugated plate, rear plate and back insulation material [12]. ..... [7] Weiss W and Rommel M 2008 Process heat collectors. State of the art within Task 33/IV.

  11. Solar Water Heater Systems for Building Trades Class.

    Science.gov (United States)

    Ryan, Milton; And Others

    This teaching unit serves as a guide for the installation of active solar water heating systems. It contains a project designed for use with secondary level students of a building trades class. Students typically would meet 2 to 3 hours per day and would be able to complete the activity within a 1-week time period. Objectives of this unit include:…

  12. Refrigerant charge management in a heat pump water heater

    Science.gov (United States)

    Chen, Jie; Hampton, Justin W.

    2014-06-24

    Heat pumps that heat or cool a space and that also heat water, refrigerant management systems for such heat pumps, methods of managing refrigerant charge, and methods for heating and cooling a space and heating water. Various embodiments deliver refrigerant gas to a heat exchanger that is not needed for transferring heat, drive liquid refrigerant out of that heat exchanger, isolate that heat exchanger against additional refrigerant flowing into it, and operate the heat pump while the heat exchanger is isolated. The heat exchanger can be isolated by closing an electronic expansion valve, actuating a refrigerant management valve, or both. Refrigerant charge can be controlled or adjusted by controlling how much liquid refrigerant is driven from the heat exchanger, by letting refrigerant back into the heat exchanger, or both. Heat pumps can be operated in different modes of operation, and segments of refrigerant conduit can be interconnected with various components.

  13. Study Design And Realization Of Solar Water Heater

    International Nuclear Information System (INIS)

    Lounis, M.; Boudjemaa, F.; Akil, S. Kouider

    2011-01-01

    Solar is one of the most easily exploitable energy, it is moreover inexhaustible. His applications are many and are varied. The heating of the domestic water is one of the most immediate, simplest and also of most widespread exploitation of the solar energy. Algeria, from its geographical situation, it deposits one of the largest high sun surface expositions in the world. The exposition duration of the almost territory exceeds 2000 hours annually and can reach the 3900 hours (high plateaus and Sahara). By knowing the daily energy received by 1 m 2 of a horizontal surface of the solar thermal panel is nearly around 1700 KWh/m 2 a year in the north and 2263 KWh/m 2 a year in the south of the country, we release the most important and strategic place of the solar technologies in the present and in the future for Algeria. This work consists to study, conceive and manufacture solar water heating with the available local materials so, this type of the energy will be profitable for all, particularly the poor countries. If we consider the illumination duration of the panel around 6 hours a day, the water heat panel manufactured in our laboratory produce an equivalent energy of 11.615 KWh a day so, 4239 KWh a year. These values of energy can be easily increased with performing the panel manufacture.

  14. 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%.

  15. 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.

  16. Experimental investigation of a Hybrid Solar Drier and Water Heater System

    International Nuclear Information System (INIS)

    Mohajer, Alireza; Nematollahi, Omid; Joybari, Mahmood Mastani; Hashemi, Seyed Ahmad; Assari, Mohammad Reza

    2013-01-01

    Highlights: • A Hybrid Solar Drier and Water Heater System experimentally investigated. • Using collected data, GIS maps were plotted for solar energy of Khuzestan Province. • System is presented which facilitates a dual-purpose solar collector. • The system includes a 100 l water storage tank, a solar dryer with 5 trays. • Experiments were carried out to dry vegetables (parsley, dill and coriander). - Abstract: Drying process is of great importance in food industries. One of the best methods of food drying is using solar dryers. For initial estimation of solar energy, calculations were made for statistical information measured by Renewable Energy Organization of Iran. Using collected data, GIS maps were plotted for solar energy of Khuzestan Province, Iran. In this study, a new hybrid system is presented which facilitates a dual-purpose solar collector to simultaneously support a dryer system and provide consumptive hot water. The system includes a 100 l water storage tank, a solar dryer with 5 trays, and a dual-purpose collector. Experiments were carried out to dry a mixture of vegetables (parsley, dill and coriander) at constant air and water flow rates. Besides, an electrical heater has been used as an auxiliary source for heating. The results indicated that the system optimally dried the vegetables and simultaneously provided the consumptive hot water

  17. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Kingston, T.; Scott, S.

    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 with the following key findings: 1) The tankless combo system maintained more stable DHW and space heating temperatures than the storage combo system. 2) The tankless combo system consistently achieved better daily efficiencies (i.e. 84%-93%) than the storage combo system (i.e. 81%- 91%) when the air handler was sized adequately and adjusted properly to achieve significant condensing operation. When condensing operation was not achieved, both systems performed with lower (i.e. 75%-88%), but similar efficiencies. 3) Air handlers currently packaged with combo systems are not designed to optimize condensing operation. More research is needed to develop air handlers specifically designed for condensing water heaters. 4) System efficiencies greater than 90% were achieved only on days where continual and steady space heating loads were required with significant condensing operation. For days where heating was more intermittent, the system efficiencies fell below 90%.

  19. Micromorphology of pelletized soil conditioners

    Science.gov (United States)

    Hirsch, Florian; Dietrich, Nils; Knoop, Christine; Raab, Thomas

    2017-04-01

    Soil conditioners produced by anaerobic digestion and subsequent composting of organic household waste, bear the potential to improve unproductive farmland together with a reduced input risk of unwanted pollutants into the soils. Within the VeNGA project (http://www.biogas-network.de/venga), soil conditioners from anaerobically digested organic household waste are tested for their potential to increase plant growth in glasshouse and field experiments. Because the production techniques of these soil conditioners may influence their physical and chemical behaviour in the soil, two different techniques for pelletizing the soil conditioners where applied. We present findings from a pot experiment with cereal that has been sampled after two months for micromorphological analyses. We visualize the decomposition and the physical behaviour of the soil conditioners. Pellets produced in an agglomeration mixer result in dense balls, that are only slightly decomposed after the trial. But the soil conditioners created under pressure in a screw extruder are rich in voids and have the potential of retaining more soil water.

  20. Diffusion of solar water heaters in regional China: Economic feasibility and policy effectiveness evaluation

    International Nuclear Information System (INIS)

    Ma, Ben; Song, Guojun; Smardon, Richard C.; Chen, Jing

    2014-01-01

    Whereas the technical feasibility of solar water heaters (SWHs) has long been established, the economic feasibility of SWHs in regional China remains to be examined. This paper constructs cost models to calculate costs per unit energy saving of SWHs in 27 Chinese provincial capital cities. The cost effectiveness of SWHs is examined at the national level. At a micro level, we analyze the financial attractiveness of consumers’ investment in SWHs. A panel data model is employed to evaluate the effectiveness of a subsidy program in rural China. The results show that SWH costs, ranging from 0.305 to 0.744 CNY/kW h, are much lower than those of other major renewable energies across China. This finding indicates that the diffusion of SWHs is a cost-effective way to reach China’s renewable energy target. For consumers, incentive programs for SWHs are needed to improve the financial attractiveness of the devices in China. Existing subsidy policies for rural China have failed to significantly enhance the deployment of SWHs. The causes of the failure are examined and a new incentive program is suggested for rural areas of the country. - Highlights: • We examine the economic feasibility of solar water heaters in 27 Chinese cities. • We evaluate policy effectiveness of solar water heaters (SWHs) using panel data. • Diffusion of SWHs is cost effective in fulfilling China’s renewable energy target. • Financial attractiveness of SWHs is limited without incentive programs. • The existing subsidy policy is proved to be a failure and a new program is suggested

  1. 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...... of the control approach are compared with a traditional thermostatic controller using historical measurements of a 10 kW PV installation. Economic results based on the Italian self consumption tariffs are also reported. The model of the water heater complex is a mixed grey and white box and its parameters have...

  2. One dimensional analysis model for condensation heat transfer in feed water heater

    International Nuclear Information System (INIS)

    Murase, Michio; Takamori, Kazuhide; Aihara, Tsuyoshi

    1998-01-01

    In order to simplify condensation heat transfer calculations for feed water heaters, one dimensional (1D) analyses were compared with three dimensional (3D) analyses. The results showed that average condensation heat transfer coefficients by 1D analyses with 1/2 rows of heat transfer tubes agreed with those by 3D analyses within 7%. Using the 1D analysis model, effects of the pitch of heat transfer tubes were evaluated. The results showed that the pitch did not affect much on heat transfer rates and that the size of heat transfer tube bundle could be decreased by a small pitch. (author)

  3. To built a solar hot water heater to work the sustainability problem

    Directory of Open Access Journals (Sweden)

    Carretero Gómez, María Begoña

    2012-01-01

    Full Text Available We are commemorating the Education Decade for Sustainable Development. If we want to create positive towards our environment and its sustainable development we have to begin working at school. It is necessary to show our students what problems of the environment are and which solutions can be adopted. That is the reason we have planned this activity in our secondary school. We do think that by doing daily activities we have a good opportunity to fulfil this goal. An example of such experiences is the fabrication of a solar hot water heater to make them and their families more environment conscience.

  4. Thermal stratification in storage tanks of integrated collector storage solar water heaters

    International Nuclear Information System (INIS)

    Oshchepkov, M.Y.; Frid, S.E.

    2015-01-01

    To determine the influence of the shape of the tank, the installation angle, and the magnitude of the absorbed heat flux on thermal stratification in integrated collector-storage solar water heaters, numerical simulation of thermal convection in tanks of different shapes and same volume was carried out. Idealized two-dimensional models were studied; auto model stratification profiles were obtained at the constant heat flux. The shape of the tank, the pattern of the heat flux dynamics, the adiabatic mixing on the circulation rate and the degree of stratification were shown to have significant influence. (authors)

  5. 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.

  6. Exergy analysis of integrated photovoltaic thermal solar water heater under constant flow rate and constant collection temperature modes

    NARCIS (Netherlands)

    Tiwari, A.; 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,

  7. Feedwater heater

    International Nuclear Information System (INIS)

    Murata, Shigeto; Minato, Akihiko; Yokomizo, Osamu; Masuhara, Yasuhiro.

    1991-01-01

    The present invention concerns a feedwater heater for a BWR type reactor. A cylinder is fit into the lower portion of a drain inlet pipe, to which drain water inflows from a turbine, and a disk is disposed to the lower end of the cylinder vertically to the axis of the cylinder, to constitute a drain water dispersing mechanism. Drain water inflown from the drain inlet pipe is fallen in the cylinder and collides against the disk. The collided drain water is splashed horizontally by its kinetic energy to reach the heat transfer pipe and conducts heat exchange. In this case, the drain water is converted into fine droplets by the collision against the disk and scattered in a wide range in the heater. As a result, sensible heat in the drain water can be transferred to feedwater effectively. Then, even the heat energy of the drain water can be utilized effectively for heat exchange, to improve the heat exchange efficiency. (I.N.)

  8. Evaluation method for two-phase flow and heat transfer in a feed-water heater

    International Nuclear Information System (INIS)

    Takamori, Kazuhide; Minato, Akihiko

    1993-01-01

    A multidimensional analysis code for two-phase flow using a two-fluid model was improved by taking into consideration the condensation heat transfer, film thickness, and film velocity, in order to develop an evaluation method for two-phase flow and heat transfer in a feed-water heater. The following results were obtained by a two-dimensional analysis of a feed-water heater for a power plant. (1) In the model, the film flowed downward in laminar flow due to gravity, with droplet entrainment and deposition. For evaluation of the film thickness, Fujii's equation was used in order to account for forced convection of steam flow. (2) Based on the former experimental data, the droplet deposition coefficient and droplet entrainment rate of liquid film were determined. When the ratio at which the liquid film directly flowed from an upper heat transfer tube to a lower heat transfer tube was 0.7, the calculated total heat transfer rate agreed with the measured value of 130 MW. (3) At the upper region of a heat transfer tube bundle where film thickness was thin, and at the outer region of a heat transfer tube bundle where steam velocity was high, the heat transfer rate was large. (author)

  9. The study of production performance of water heater manufacturing by using simulation method

    Science.gov (United States)

    Iqbal, M.; Bamatraf, OAA; Tadjuddin, M.

    2018-02-01

    In industrial companies, as demand increases, decision-making to increase production becomes difficult due to the complexity of the model systems. Companies are trying to find the optimum methods to tackle such problems so that resources are utilized and production is increased. One line system of a manufacturing company in Malaysia was considered in this research. The Company produces several types of water heater and each type went into many processes, which was divided into twenty six sections. Each section has several operations. The main type of the product was 10G water heater which is produced most compare to other types, hence it was taken under consideration to be studied in this research. It was difficult to find the critical section that could improve the productions of the company. This research paper employed Delmia Quest software, Distribution Analyser software and Design of Experiment (DOE software) to simulate one model system taken from the company to be studied and to find the critical section that will improve the production system. As a result, assembly of inner and outer tank section were found to be the bottleneck section. Adding one section to the bottleneck increases the production rate by four products a day. The buffer size is determined by the experiment was six items.

  10. Condensation heat transfer of a feed-water heater and improvement of its performance

    International Nuclear Information System (INIS)

    Takamori, Kazuhide; Murase, Michio; Baba, Yoshikazu; Aihara, Tsuyoshi

    1995-01-01

    In this study, a condensation heat transfer model, coupled with a three-dimensional two-phase flow analysis, was developed. In the heat transfer model, the liquid film flow rate on the heat transfer tubes was calculated by a mass balance equation and the liquid film thickness was calculated from the liquid film flow rate using Nusselt's laminar flow model and Fujii's equation for the steam velocity effect. The model was verified by condensation heat transfer experiments. In the experiments, 112 horizontal, staggered tubes with an outer diameter of 16mm and length of 0.55m were used. The calculated over-all heat transfer coefficients agreed with the data within ±5% under the inlet quality conditions of 13-100%. Based on a three-dimensional two-phase flow analysis, an improved feed-water heater with support plates, which have flow holes between the upper and lower tube bundles, was designed. The total heat exchange capacity of the improved feed-water heater increased about 6%. (author)

  11. 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.

  12. Relationship between Organic Carbon and Opportunistic Pathogens in Simulated Glass Water Heaters.

    Science.gov (United States)

    Williams, Krista; Pruden, Amy; Falkinham, Joseph O; Edwards, Marc; Williams, Krista; Pruden, Amy; Falkinham, Joseph O; Edwards, Marc

    2015-06-09

    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.

  13. Air conditioner

    International Nuclear Information System (INIS)

    Sato, Masaaki

    1993-01-01

    The present invention provides an air conditioner which can prevent an undesirable effects on a human body due to radon daughter nuclides in a closed space. That is, the concentration of the radon daughter nuclides in the air in the closed space is continuously measured. A necessary amount of ventilation air is determined based on the measured concentration to generate control signals. External air is introduced into the closed space by the generated control signals. With such procedures, necessary amount of external air is taken from the atmospheric air which can be regarded to have the radon daughter nuclide concentration substantially at zero, thereby enabling to reduce the concentration of the radon daughter nuclides in the closed space. As a result, undesired effects on the human body due to the radon daughter nuclides staying in the closed space can be prevented. According to simulation, the radon daughter nuclides are rapidly decreased only by ventilation only for three times or so in one hour. Accordingly, ventilation is extremely effective and convenient means as a countermeasure for the radon daughter nuclides. (I.S.)

  14. Thermal performance analysis of a direct-expansion solar-assisted heat pump water heater

    International Nuclear Information System (INIS)

    Kong, X.Q.; Zhang, D.; Li, Y.; Yang, Q.M.

    2011-01-01

    A direct-expansion solar-assisted heat pump water heater (DX-SAHPWH) is described, which can supply hot water for domestic use during the whole year. The system mainly employs a bare flat-plate collector/evaporator with a surface area of 4.2 m 2 , an electrical rotary-type hermetic compressor, a hot water tank with the volume of 150 L and a thermostatic expansion valve. R-22 is used as working fluid in the system. A simulation model based on lumped and distributed parameter approach is developed to predict the thermal performance of the system. Given the structure parameters, meteorological parameters, time step and final water temperature, the numerical model can output operational parameters, such as heat capacity, system COP and collector efficiency. Comparisons between the simulation results and the experimental measurements show that the model is able to give satisfactory predictions. The effect of various parameters, including solar radiation, ambient temperature, wind speed and compressor speed, has been analyzed on the thermal performance of the system. -- Highlights: ► A direct-expansion solar-assisted heat pump water heater (DX-SAHPWH) is described. ► A simulation model based on lumped and distributed parameter approach is developed to predict the thermal performance of the system. ► The numerical model can output operational parameters, such as heat capacity, system COP and collector efficiency. ► Comparisons between the simulation results and the experimental measurements show that the model is able to give satisfactory predictions. ► The effect of various parameters has been analyzed on the thermal performance of the system.

  15. 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

  16. Study of an improved integrated collector-storage solar water heater combined with the photovoltaic cells

    International Nuclear Information System (INIS)

    Ziapour, Behrooz M.; Palideh, Vahid; Mohammadnia, Ali

    2014-01-01

    Highlights: • Simulation of an enhanced ICSSWH system combined with PV panel was conducted. • The present model dose not uses any photovoltaic driven water pump. • High packing factor and tank water mass are caused to high PVT system efficiency. • Larger area of the collector is resulted to lower total PVT system efficiency. - Abstract: A photovoltaic–thermal (PVT) module is a combination of a photovoltaic (PV) panel and a thermal collector for co-generation of heat and electricity. An integrated collector-storage solar water heater (ICSSWH) system, due to its simple and compact structure, offers a promising approach for the solar water heating in the varied climates. The combination of the ICSSWH system with a PV solar system has not been reported. In this paper, simulation of an enhanced ICSSWH system combined with the PV panel has been conducted. The proposed design acts passive. Therefore, it does not use any photovoltaic driven water pump to maintain a flow of water inside the collector. The effects of the solar cell packing factor, the tank water mass and the collector area on the performance of the present PVT system have been investigated. The simulation results showed that the high solar cell packing factor and the tank water mass are caused to the high total PVT system efficiency. Also, larger area of the collector is resulted to lower total PVT system efficiency

  17. A viable CDM model for solar water heaters; CDM-Clean Development Mechanism

    Energy Technology Data Exchange (ETDEWEB)

    2008-09-15

    It is a well known fact that solar water Heaters (SWH) replace fossil fuels and they do not represent business as usual scenario. Therefore use of this appliance can qualify to be considered as Clean Development Mechanism (CDM) project. However a single solar water heater is a very small unit to be able to generate sufficient Certified Emission Reductions (CERs) to pursue it as a CDM project. Even if the project is considered at the level of local venders or at the level of a company engaged in manufacturing SWH, the CERs still remain very small. The study examines the size of the project from the perspective of its viability as a CDM project and also explores other related issues such as additionality requirement, selection of methodology, baseline calculations, approach for stakeholders' comments, potential bundlers, monitoring and verification, and required policy interventions. Bank of Maharashtra (BOM), a commercial bank in India engaged in financing Solar Water Heaters (SWH), was considered as the base for the study. The CERs were calculated considering Electricity and LPG as the baseline. For the purpose of sensitivity analysis, various price bands for CERs (between US$ 15-25/CER) were considered. The analysis was carried out with bundling of SWH at BOM level, and at the Association of Banks (AOB) / Ministry level (in which case SWH financed by several banks are bundled). Recently approved Programme of Activities (PoA) approach was also considered in the analysis. The analysis clearly indicated that: 1) The CDM project with bundling at an individual bank level with about 8600 installations, though cash surplus, would generate the cash just to meet its own sustainability. But it is a very small project. 2) Bundling of installations by various banks, through an entity such as Association of Banks, would be a viable and sustainable CDM project due to benefits arising out of scale of economy. 3) The profitability of the CDM project would improve further if

  18. Performance evaluation of an integrated solar water heater as an option for building energy conservation

    Energy Technology Data Exchange (ETDEWEB)

    Dharuman, C.; Arakeri, J.H.; Srinivasan, K. [Indian Inst. of Science, Bangalaore (India). Dept. of Mechanical Engineering

    2006-03-15

    Since a majority of residential and industrial building hot water needs are around 50 {sup o}C, an integrated solar water heater could provide a bulk source that blends collection and storage into one unit. This paper describes the design, construction and performance test results of one such water-heating device. The test unit has an absorber area of 1.3 m{sup 2} and can hold 170 l of water, of which extractable volume per day is 100 l. Its performance was evaluated under various typical operating conditions. Every morning at about 7:00 a.m., 100 l of hot water were drawn from the sump and replaced with cold water from the mains. Although, during most of the days, the peak temperatures of water obtained are between 50 and 60 {sup o}C, the next morning temperatures were lower at 45-50 {sup o}C. Daytime collection efficiencies of about 60% and overall efficiencies of about 40% were obtained. Tests were conducted with and without stratification. Night radiation losses were reduced by use of a screen insulation. (author)

  19. In-situ tuff water migration/heater experiment: experimental plan

    International Nuclear Information System (INIS)

    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 (less than or equal to 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

  20. Bifurcated SEN with Fluid Flow Conditioners

    Directory of Open Access Journals (Sweden)

    F. Rivera-Perez

    2014-01-01

    Full Text Available This work evaluates the performance of a novel design for a bifurcated submerged entry nozzle (SEN used for the continuous casting of steel slabs. The proposed design incorporates fluid flow conditioners attached on SEN external wall. The fluid flow conditioners impose a pseudosymmetric pattern in the upper zone of the mold by inhibiting the fluid exchange between the zones created by conditioners. The performance of the SEN with fluid flow conditioners is analyzed through numerical simulations using the CFD technique. Numerical results were validated by means of physical simulations conducted on a scaled cold water model. Numerical and physical simulations confirmed that the performance of the proposed SEN is superior to a traditional one. Fluid flow conditioners reduce the liquid free surface fluctuations and minimize the occurrence of vortexes at the free surface.

  1. Local market of solar water heaters in Taiwan. Review and perspectives

    International Nuclear Information System (INIS)

    Chang, K.C.; Lee, T.S.; Chung, K.M.; Lin, W.M.

    2009-01-01

    For promotion of solar water heaters in Taiwan, incentive programs were first initiated from 1986 to 1991 and re-initiated from 2000 to the present. The subsidies create an economic incentive for the end users and have been rather instrumental at the initial stage of each program but lost their significance thereafter. To analyze the behavior of the major actors in the local market, two questionnaires were developed. One was addressed to sales and distribution agents while the other one consisted of person-to-person interviews with household owners. The market-driven mechanism is a multi-parametric phenomenon. Other than the capital cost and energy price (cost to benefit), architectural type of buildings (or degree of urbanization) and household composition play the major roles in market diffusion. (author)

  2. 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.

  3. 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

    Overvoltage (OV) in a low voltage distribution network is one of the foremost issues observed even under moderate penetration of rooftop solar photovoltaics (PVs). Similarly, grid under-voltage (UV) is foreseen as a potential issue resulting from increased integration of large flexible loads......, 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...... and reactive power injection/consumptions of the EWHs and PVs following the voltage violations. To effectively support the network in real-time, the controller allows EWHs to operate prior to PVs in OV and after the PVs in UV violations. The effectiveness of the proposed control strategy is demonstrated...

  4. Thermal performance of an integrated collector storage solar water heater (ICSSWH) with phase change materials (PCM)

    International Nuclear Information System (INIS)

    Chaabane, Monia; Mhiri, Hatem; Bournot, Philippe

    2014-01-01

    Highlights: • We study the effect of phase change materials integration on the thermal performances of an ICSSWH. • Two kinds and tree radiuses of the PCM layer are studied and the most appropriate design is presented. • The use of phase change materials in ICSSWH is determined to reduce the night thermal losses. • Myristic acid is the most appropriate PCM for this application regarding the daily and night operation. - Abstract: In this paper, we propose a numerical study of an integrated collector storage solar water heater (ICSSWH). Two numerical models in three-dimensional modeling are developed. The first one which describes a sensible heat storage unit (SHSU), allowing validating the numerical model. Based on the good agreement between numerical results and experimental data from literature, and as this type of solar water heater presents the disadvantage of its high night losses, we propose to integrate a phase change material (PCM) directly in the collector and to study its effect on the ICSSWH thermal performance. Indeed, a second 3D CFD model is developed and series of numerical simulations are conducted for two kind (myristic acid and RT42-graphite) and three radiuses (R = 0.2 m, R = 0.25 m and R = 0.3 m) of this PCM layer. Numerical results show that during the day-time, the latent heat storage unit (LHSU) performs better than the sensible one when myristic acid is used as PCM. Regarding the night operating of this solar system, it is found that the LHSU is more effective for both PCMs as it allows lower thermal losses and better heat preservation

  5. 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...

  6. Analysis of solar water heater with parabolic dish concentrator and conical absorber

    Science.gov (United States)

    Rajamohan, G.; Kumar, P.; Anwar, M.; Mohanraj, T.

    2017-06-01

    This research focuses on developing novel technique for a solar water heating system. The novel solar system comprises a parabolic dish concentrator, conical absorber and water heater. In this system, the conical absorber tube directly absorbs solar radiation from the sun and the parabolic dish concentrator reflects the solar radiations towards the conical absorber tube from all directions, therefore both radiations would significantly improve the thermal collector efficiency. The working fluid water is stored at the bottom of the absorber tubes. The absorber tubes get heated and increases the temperature of the working fluid inside of the absorber tube and causes the working fluid to partially evaporate. The partially vaporized working fluid moves in the upward direction due to buoyancy effect and enters the heat exchanger. When fresh water passes through the heat exchanger, temperature of the vapour decreases through heat exchange. This leads to condensation of the vapour and forms liquid phase. The working fluid returns to the bottom of the collector absorber tube by gravity. Hence, this will continue as a cyclic process inside the system. The proposed investigation shows an improvement of collector efficiency, enhanced heat transfer and a quality water heating system.

  7. 14 CFR 23.859 - Combustion heater fire protection.

    Science.gov (United States)

    2010-01-01

    ... relief of any backfire that, if so restricted, could cause heater failure. (d) Heater controls: general. Provision must be made to prevent the hazardous accumulation of water or ice on or in any heater control... heater in case of leakage. (2) The region surrounding the heater, if the heater fuel system has fittings...

  8. Evaluation of the service quality of solar water-heaters; Evaluation de la qualite de service des chauffe-eau solaires

    Energy Technology Data Exchange (ETDEWEB)

    Buscarlet, C.; Filloux, A.

    1998-12-31

    This small booklet is the result of research studies carried out for the evaluation of solar water-heater performances, including service quality. Service quality is evaluated according to the capacity of production of `useful` hot water (hot water above a given temperature) and to the influence of the daily profile of drawing up on the performances of the water-heater. Procedures have been developed that allow to determine these indicators without the need of supplementary tests. A suggestion of information file for solar water-heaters without auxiliary heating is proposed which presents for each type of apparatus a synthetic information about its performances and service quality. (J.S.)

  9. How to reduce risk of climate change: Domestic hot water production methanization and programmed timing of heaters

    International Nuclear Information System (INIS)

    Silvestrini, G.

    1992-01-01

    This paper first identifies a significant and deleterious trend, in terms of poor energy efficiency and high carbon dioxide emissions, towards the increased use of electric water heaters for sanitary hot water production in single family units. It then points out how the use of wall mounted methane fired boilers can result in overall energy savings (overall electric power consumption for domestic hot water production is estimated to represent one- quarter of Italy's total domestic power demand), as well as air pollution abatement. The feasibility of other methods of energy conservation and pollution abatement in domestic water heating are also examined. These include the use of solar hot water heaters, computerized timers which allow users to program the operation of their heating plants, and the adoption by residential communities of methane fuelled district heating plants

  10. 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

  11. Experimental analysis of distinct design of a batch solar water heater with integrated collector storage system

    Directory of Open Access Journals (Sweden)

    Varghese Jaji

    2007-01-01

    Full Text Available The performance of a new design of batch solar water heater has been studied. In this system, the collector and storage were installed in one unit. Unlike the conventional design consisting of small diameter water tubes, it has a single large diameter drum which serves the dual purpose of absorber tube and storage tank. In principle it is a compound parabolic collector. The drum is sized to have a storage capacity of 100 liter to serve a family of four persons. The tests were carried out with a single glass cover and two glass covers. The tests were repeated for several days. Performance analysis of the collector has revealed that it has maximum mean daily efficiency with two glass covers as high as 37.2%. The maximum water temperature in the storage tank of 60°C has been achieved for a clear day operation at an average solar beam radiation level of 680 W/m2 and ambient temperature of 32°C. To judge the operating characteristics and to synchronize utility pattern of the collector, the different parameters such as efficiency, mean plate temperature and mass flow rate has been investigated.

  12. Second-law analysis of a two-phase self-pumping solar water heater

    International Nuclear Information System (INIS)

    Walker, H.A.; Davidson, J.H.

    1992-01-01

    In this paper entropy generated by operation of a two-phase self-pumping solar water heater under Solar Rating and Certification Corporation rating conditions is computed numerically in a methodology based on an exergy cascade. An order of magnitude analysis shows that entropy generation is dominated by heat transfer across temperature differences. Conversion of radiant solar energy incident on the collector to thermal energy within the collector accounts for 87.1 percent of total entropy generation. Thermal losses are responsible for 9.9 percent of total entropy generation, and heat transfer across the condenser accounts for 2.4 percent of the total entropy generation. Mixing in the tempering valve is responsible for 0.7 percent of the total entropy generation. Approximately one half of the entropy generated by thermal losses is attributable to the self-pumping process. The procedure to determine total entropy generation can be used in a parametric study to evaluate the performance of two-phase hot water heating systems relative to other solar water heating options

  13. Experimental and theoretical evaluation of the performance of a tar solar water heater

    International Nuclear Information System (INIS)

    Ammari, H.D.; Nimir, Y.L.

    2003-01-01

    The paper presents an experimental and theoretical evaluation of the performance of a tar solar water heater and comparison with that of a conventional type collector. The performance of both collectors is assessed under the same conditions. Both of the collectors have the same surface area and are glazed. The conventional type has the water tubes welded to the absorber plate, whereas in the tar type, the tar acts as an absorber plate that covers the water tubes. The theoretical model for each collector type, with the transient effects taken into account, is based on a control volume and a time base in the related energy equations. By considering a small element of the collector in each case, three partial differential equations were developed for each collector and were solved numerically by the Runge-Kutta method of the fifth order. A good agreement was achieved between the numerical and experimental results for both the conventional and tar collectors, indicating the feasibility of employing the theoretical model in the design of flat plate solar collectors. The results also showed that the conventional collector is more efficient than the tar type during most of the daylight, but the tar collector had the added advantage of better conservation of energy in late afternoon and evening

  14. Experimental performance analysis on a direct-expansion solar-assisted heat pump water heater

    International Nuclear Information System (INIS)

    Li, Y.W.; Wang, R.Z.; Wu, J.Y.; Xu, Y.X.

    2007-01-01

    A direct expansion solar assisted heat pump water heater (DX-SAHPWH) experimental set-up is introduced and analyzed. This DX-SAHPWH system mainly consists of 4.20 m 2 direct expansion type collector/evaporator, R-22 rotary-type hermetic compressor with rated input power 0.75 kW, 150 L water tank with immersed 60 m serpentine copper coil and external balance type thermostatic expansion valve. The experimental research under typical spring climate in Shanghai showed that the COP of the DX-SAHPWH system can reach 6.61 when the average temperature of 150 L water is heated from 13.4 deg. C to 50.5 deg. C in 94 min with average ambient temperature 20.6 deg. C and average solar radiation intensity 955 W/m 2 . And the COP of the DX-SAHPWH system is 3.11 even if at a rainy night with average ambient temperature 17.1 deg. C. The seasonal average value of the COP and the collector efficiency was measured as 5.25 and 1.08, respectively. Through exergy analysis for each component of the DX-SAHPWH system, it can be calculated that the highest exergy loss occurs in the compressor, followed by collector/evaporator, condenser and expansion valve, respectively. Further more, some methods are suggested to improve the thermal performance of each component and the whole DX-SAHPWH system

  15. 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 %.

  16. Numerical analysis of using hybrid photovoltaic-thermal solar water heater in Iran

    Directory of Open Access Journals (Sweden)

    M Mohammadi Sarduei

    2017-05-01

    Full Text Available Introduction Electrical performance of solar cells decreases with increasing cell temperature, basically because of growth of the internal charge carrier recombination rates, caused by increased carrier concentrations. Hybrid Photovoltaic/thermal (PVT systems produce electrical and thermal energy simultaneously. PVT solar collectors convert the heat generated in the solar cells to low temperature useful heat energy and so they provide a lower working temperature for solar cells which subsequently leads to a higher electrical efficiency. Recently, in Iran, the reforming government policy in subsidy and increasing fossil fuels price led to growing an interest in use of renewable energies for residual and industrial applications. In spite of this, the PV power generator investment is not economically feasible, so far. Hybrid PVT devices are well known as an alternative method to improve energy performance and therefore economic feasibility of the conventional PV systems. The aim of this study is to investigate the performance of a PVT solar water heater in four different cities of Iran using TRNSYS program. Materials and Methods The designed PVT solar water system consists of two separate water flow circuits namely closed cycle and open circuit. The closed cycle circuit was comprised of a solar PVT collector (with nominal power of 880 W and area of 5.6 m2, a heat exchanger in the tank (with volume of 300 L, a pump and connecting pipes. The water stream in the collector absorbs the heat accumulated in the solar cells and delivers it to the water in the tank though the heat exchanger. An on/off controller system was used to activate the pump when the collector outlet temperature was higher than that of the tank in the closed cycle circuit. The water in the open circuit, comes from city water at low temperature, enters in the lower part of the storage tank where the heat transfer occurs between the two separate circuits. An auxiliary heater, connected

  17. Predictive Power of Machine Learning for Optimizing Solar Water Heater Performance: The Potential Application of High-Throughput Screening

    Directory of Open Access Journals (Sweden)

    Hao Li

    2017-01-01

    Full Text Available Predicting the performance of solar water heater (SWH is challenging due to the complexity of the system. Fortunately, knowledge-based machine learning can provide a fast and precise prediction method for SWH performance. With the predictive power of machine learning models, we can further solve a more challenging question: how to cost-effectively design a high-performance SWH? Here, we summarize our recent studies and propose a general framework of SWH design using a machine learning-based high-throughput screening (HTS method. Design of water-in-glass evacuated tube solar water heater (WGET-SWH is selected as a case study to show the potential application of machine learning-based HTS to the design and optimization of solar energy systems.

  18. 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)

  19. Building America Case Study: Multifamily Central Heat Pump Water Heaters, Davis, California

    Energy Technology Data Exchange (ETDEWEB)

    M. Hoeschele, E. Weitzel

    2017-03-01

    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.

  20. 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.

  1. 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.

  2. 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

  3. The Impact of Water Quality on the Use of Solar Water Heaters in Remote Islands of Taiwan

    Directory of Open Access Journals (Sweden)

    Kai-Chun Fan

    2016-11-01

    Full Text Available The use of solar water heaters (SWHs in Taiwan’s remote islands has been subjected to scaling and, in particular, corrosion problems due to sources of water. In this study, four different water quality indices including the Langelier Saturation Index (LSI, the Ryznar Stability Index (RSI, the Puckorius Scaling Index (PSI, and the Larson-Skold Corrosive Index (LSCI were employed to assess the scaling and corrosion tendencies in SWHs caused by tap water and ground water in the Penghu, Kinmen, and Lienchiang counties, each of which is constituted of several remote islands. In general, the LSI, the RSI, and the PSI results show a slight scaling tendency in Penghu, but a corrosion tendency in Kinmen and Lienchiang. Nevertheless, all LSCI results show a serious steel corrosion tendency in these three counties. In addition, the chloride ion (Cl− concentrations are higher than 45 mg/L in either tap water (except for the Lieyu township in Kinmen or ground water. This fact resulted in serious corrosion problems, as found in the currently installed SWHs, which were mainly made from 304 stainless steel. The metals with higher corrosion resistance to chloride ions are required in the manufacture of SWHs to be installed on these three remote-island counties.

  4. The potential and reality of the solar water heater programme in South African townships: Lessons from the City of Tshwane

    International Nuclear Information System (INIS)

    Curry, Claire; Cherni, Judith A.; Mapako, Maxwell

    2017-01-01

    The South African solar water heater (SWH) programme is part of national policy to improve the country's electricity security, an innovative strategy to provide indigent households with free solar water heaters. The study assesses the effects of the government programme for poor townships on reduction of household electricity consumption, decline in energy poverty, and reduction in CO2 emissions; and estimates the impact of SWH on reducing electricity demand nationwide. It reports results from fieldwork carried out in the City of Tshwane to measure both quantitatively and qualitatively the success of the project's deployment in townships. Although households register average savings of 27% on their monthly electricity bills and off-peak electricity demand has reduced significantly in the area, a variety of problems prevented the project from attaining the desired level of impact. Difficulties encountered include technical faults with the heaters combined with nonavailability of maintenance; a rise in water consumption; lack of community engagement leading to apathy; and dearth of owner training leading to underuse. The gap between inflated estimates and real savings is discussed. Expanding the programme could generate jobs but significant challenges remain. - Highlights: • The government's aim of saving electricity and reducing utility bills partly achieved. • Savings of electricity are estimated at about 25% less than the potential saving. • Wrong assumption that peak time is only 1 h produced savings 5 times larger. • ESKOM & government overlooked providing Information on the SWH to the householders. • No maintenance led to abandonment by many or water leaking increasing utility bills.

  5. Experimental performance analysis and optimization of a direct expansion solar-assisted heat pump water heater

    International Nuclear Information System (INIS)

    Li, Y.W.; Wang, R.Z.; Wu, J.Y.; Xu, Y.X.

    2007-01-01

    In this study, a direct expansion solar-assisted heat pump water heater (DX-SAHPWH) with rated input power 750 W was tested and analyzed. Through experimental research in spring and thermodynamics analysis about the system performance, some suggestions for the system optimization are proposed. Then, a small-type DX-SAHPWH with rated input power 400 W was built, tested and analyzed. Through exergy analysis for each component of DX-SAHPWH (A) and (B), it can be seen that the highest exergy loss occurs in the compressor and collector/evaporator, followed by the condenser and expansion valve, respectively. Furthermore, some methods are suggested to improve the performance of each component, especially the collector/evaporator. A methodology for the design optimization of the collector/evaporator was introduced and applied. In order to maintain a proper matching between the heat pumping capacity of the compressor and the evaporative capacity of the collector/evaporator under widely varying ambient conditions, the electronic expansion valve and variable frequency compressor are suggested to be utilized for the DX-SAHPWH

  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. High Efficiency Water Heating Technology Development Final Report, Part II: CO2 and Absorption-Based Residential Heat Pump Water Heater Development

    Energy Technology Data Exchange (ETDEWEB)

    Gluesenkamp, Kyle R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Abdelaziz, Omar [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Patel, Viral K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Mandel, Bracha T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); de Almeida, Valmor F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-05-01

    The two objectives of this project were to 1.demonstrate an affordable path to an ENERGY STAR qualified electric heat pump water heater (HPWH) based on low-global warming potential (GWP) CO2 refrigerant, and 2.demonstrate an affordable path to a gas-fired absorption-based heat pump water heater with a gas energy factor (EF) greater than 1.0. The first objective has been met, and the project has identified a promising low-cost option capable of meeting the second objective. This report documents the process followed and results obtained in addressing these objectives.

  8. A parametric study on a humidification–dehumidification (HDH) desalination unit powered by solar air and water heaters

    International Nuclear Information System (INIS)

    Yıldırım, Cihan; Solmuş, İsmail

    2014-01-01

    Highlights: • A time dependent humidification–dehumidification desalination process is investigated. • Fourth-order Runge–Kutta method is used to simulate the problem. • Daily and annual performance are examined. • Various operational parameters are investigated. - Abstract: The performance of a solar powered humidification–dehumidification desalination system is theoretically investigated for various operating and design parameters of the system under climatological conditions of Antalya, Turkey. The primary components of the system are a flat plate solar water heater, a flat plate double pass solar air heater, a humidifier, a dehumidifier and a storage tank. The mathematical model of the system is developed and governing conservation equations are numerically solved by using the Fourth order Runge–Kutta method. Daily and annual yields are calculated for different configurations of the system such as only water heating, only air heating and water–air heating

  9. Experimental validation of dynamic simulation of the flat plate collector in a closed thermosyphon solar water heater

    International Nuclear Information System (INIS)

    Taherian, H.; Rezania, A.; Sadeghi, S.; Ganji, D.D.

    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 of the absorber and center of the glass cover temperatures, were obtained. The simulation results were then compared with the experimental results in fall and showed a good agreement.

  10. Prediction of photovoltaic and solar water heater diffusion and evaluation of promotion policies on the basis of consumers’ choices

    International Nuclear Information System (INIS)

    Yamaguchi, Yohei; Akai, Kenju; Shen, Junyi; Fujimura, Naoki; Shimoda, Yoshiyuki; Saijo, Tatsuyoshi

    2013-01-01

    Highlights: ► Consumers’ preference on PV and solar water heater were investigated. ► Diffusion of the technologies in Japan was modeled by using Bass diffusion model. ► Policy measures to diffuse the technologies were evaluated by using the framework. ► Subsidy is more cost effective than FIT to diffuse PV. ► Public perception is the bottleneck of diffusion of solar water heater. -- Abstract: This paper proposes an integrated analytical framework consisting of the following three steps: (1) investigation of consumers’ preferences, (2) prediction of technology diffusion by taking into account consumers’ preferences, and (3) estimation of CO 2 emission reduction caused by the diffusion of the examined technology. By using this framework, this paper evaluates the policy measures implemented for disseminating photovoltaics and solar water heaters in terms of the contribution to reducing CO 2 emissions from the residential sector. We investigated consumer preferences for these technologies as well as the effects of attributes such as installation cost, energy price, energy efficiency, and perception on consumers’ choices. Considering these effects, we developed a model that estimates the diffusion of these technologies into the residential sector of Japan through 2025 and the resulting CO 2 emission reduction. We found that the policy measures for the diffusion of photovoltaics that reduce initial cost (e.g., subsidy programs) are more cost effective for reducing CO 2 emission than those reducing users’ operating expenditure (e.g., feed-in tariff programs). For solar water heater to be able to reduce the CO 2 emissions considerably, the public perception must be improved.

  11. Development of Low-Cost Solar Water Heater Using Recycled Solid Waste for Domestic Hot Water Supply

    Directory of Open Access Journals (Sweden)

    Talib Din Abdul

    2018-01-01

    Full Text Available This research is focused on the development of a low-cost solar water heater (SWH system by utilizing solid waste material as part of system elements. Available technologies of the solar water heater systems, heat collectors and its components were reviewed and the best system combinations for low cost design were chosen. The passive-thermosiphon system have been chosen due to its simplicity and independency on external power as well as conventional pump. For the heat collector, flat plate type was identified as the most suitable collector for low cost design and suits with Malaysia climate. Detail study on the flat plate collector components found that the heat absorber is the main component that can significantly reduce the solar collector price if it is replaced with recycled solid waste material. Review on common solid wastes concluded that crushed glass is a non-metal material that has potential to either enhance or become the main heat absorber in solar collector. A collector prototype were then designed and fabricated based on crashed glass heat collector media. Thermal performance test were conducted for three configurations where configuration A (black painted aluminum absorber used as benchmark, configuration B (crushed glass added partially that use glass for improvement, and lastly configuration C (black colored crushed glass that use colored glass as main absorber. Result for configuration B have shown a negative effect where the maximum collector efficiency is 26.8% lower than configuration A. Nevertheless, configuration C which use black crushed glass as main heat absorber shown a comparable maximum efficiency which is at 82.5% of the maximum efficiency for configuration A and furthermore have shown quite impressive increment of efficiency at the end of the experiment. Hence, black colored crushed glass is said to have quite a good potential as the heat absorber material and therefore turn out to be a new contender to other non

  12. 即热式热水器的界定和安全隐患%Definition and Safety Risks of Instantaneous Water Heaters

    Institute of Scientific and Technical Information of China (English)

    陈嘉声; 胡晴宇; 沈冬波

    2015-01-01

    Describe the definition and classification of open-outlet water heater and closed water heater, analysis safety requirements of open-outlet water heater and closed water heater through using and inter-nal structure,Analysis Safety risks caused by the wrong instal ation method.%通过对敞开式热水器和封闭式热水器的定义明确两者的分类和界定,从使用方式和内部结构的角度分析敞开式热水器和封闭式热水器的安全要求,分析错误的安装方式所带来的安全隐患。

  13. Sustainable implementation of solar tunnel dryers, water heaters and cookers in Nepal

    Energy Technology Data Exchange (ETDEWEB)

    Kovacs, Peter [Danish Energy Management, DEM for Renewable Energy Project, REP, Dhobighat, Lalitpur (Nepal); Shrestha, Niraj; Shakya, Prajwal Raj [Renewable Energy Project, REP, Dhobighat, Lalitpur (Nepal); Pokharel, Govind [Alternative Energy Promotion Centre (AEPC), Lalitpur (Nepal)

    2008-07-01

    The Renewable Energy Project (REP) is a joint effort of the European Union and the Government of Nepal. Main objectives of the project are to create renewable energy infrastructure and services for the benefit of rural people in remote districts of Nepal. The REP will provide solar energy systems for public services in remote districts, as well as for income generating activities e.g. agro business and tourism. The REP focuses on the installation of institutional PV systems with a total capacity of 0.850 MWp. Concurrently, a number of solar thermal systems are being provided to community organizations (COs) in rural areas of Nepal. The priority applications for the solar thermal part are solar tunnel dryers for small industries drying vegetables. fruits and herbs, solar water heaters for community centers in trekking areas and large scale solar cookers in schools. The paper describes the Renewable Energy Project's implementation program for solar thermal technology and in particular the implications on design and usefulness of the solar tunnel dryer from on-site feasibility studies carried out by the project team. REP provides a framework for a sustainable implementation of these systems by carrying out the whole process from dissemination of information to demand collection, feasibility studies, design, procurement, commissioning and user training. Hand over of ownership will take place once the equipment is installed and successfully commissioned. Monitoring during the first year of operation should conclude the project. REP is co-funded by the European Union and the Government of Nepal. (orig.)

  14. High Efficiency Water Heating Technology Development Final Report. Part I, Lab/Field Performance Evaluation and Accelerated Life Testing of a Hybrid Electric Heat Pump Water Heater (HPWH)

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, Van D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Murphy, Richard W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Rice, C. Keith [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Linkous, Randall Lee [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-04-01

    DOE has supported efforts for many years with the objective of getting a water heater that uses heat pump technology (aka a heat pump water heater or HPWH) successfully on the residential equipment market. The most recent previous effort (1999-2002) produced a product that performed very well in ORNL-led accelerated durability and field tests. The commercial partner for this effort, Enviromaster International (EMI), introduced the product to the market under the trade name Watter$aver in 2002 but ceased production in 2005 due to low sales. A combination of high sales price and lack of any significant infrastructure for service after the sale were the principal reasons for the failure of this effort. What was needed for market success was a commercial partner with the manufacturing and market distribution capability necessary to allow economies of scale to lead to a viable unit price together with a strong customer service infrastructure. General Electric certainly meets these requirements, and knowing of ORNL s expertise in this area, approached ORNL with the proposal to partner in a CRADA to produce a high efficiency electric water heater. A CRADA with GE was initiated early in Fiscal Year, 2008. GE initially named its product the Hybrid Electric Water Heater (HEWH).

  15. 14 CFR 25.859 - Combustion heater fire protection.

    Science.gov (United States)

    2010-01-01

    ..., could cause heater failure. (d) Heater controls; general. Provision must be made to prevent the hazardous accumulation of water or ice on or in any heater control component, control system tubing, or... leakage. (2) The region surrounding the heater, if the heater fuel system has fittings that, if they...

  16. Thermodynamic analysis of vapor compression heat pump cycle for tap water heating and development of CO_2 heat pump water heater for residential use

    International Nuclear Information System (INIS)

    Saikawa, Michiyuki; Koyama, Shigeru

    2016-01-01

    Highlights: • The ideal vapor compression cycle for tap water heating and its COP were defined. • It was verified theoretically that CO_2 achieves the highest COP for tap water heating. • The prototype of CO_2 heat pump water heater for residential use was developed. • Further COP improvement of CO_2 heat pump water heater was estimated. - Abstract: The ideal vapor compression cycle for tap water heating and its coefficient of performance (COP) have been studied theoretically at first. The ideal cycle is defined as the cycle whose high temperature heat source varies temperature with constant specific heat and other processes are same as the reverse Carnot cycle. The COP upper limit of single stage compression heat pump cycle for tap water heating with various refrigerants such as fluorocarbons and natural refrigerants was calculated. The refrigerant which achieves the highest COP for supplying hot water is CO_2. Next, the prototype of CO_2 heat pump water heater for residential use has been developed. Its outline and experimental results are described. Finally its further possibility of COP improvement has been studied. The COP considered a limit from a technical point of view was estimated about 6.0 at the Japanese shoulder season (spring and autumn) test condition of heating water from 17 °C to 65 °C at 16 °C heat source air temperature (dry bulb)/12 °C (wet bulb).

  17. 78 FR 2340 - Energy Conservation Program: Test Procedures for Residential Water Heaters and Commercial Water...

    Science.gov (United States)

    2013-01-11

    ... corresponded to the levels in the American Society of Heating, Refrigerating and Air Conditioning Engineers... provides a brief history of DOE's more recent test procedure rulemakings related to residential water... performance (e.g., such as ambient air temperature, ambient relative humidity, and inlet water temperature...

  18. Simulation analysis on dynamic performance of a combined solar/air dual source heat pump water heater

    International Nuclear Information System (INIS)

    Deng, Weishi; Yu, Jianlin

    2016-01-01

    Highlights: • A modified direct expansion solar-assisted heat pump water heater is investigated. • An additional air source evaporator is used in parallel way in the M-DX-SHPWH system. • The M-DX-SHPWH system displays a higher performance at the low solar radiation. • Effects of solar radiation and air temperature on the performance are discussed. - Abstract: This paper investigated a combined solar/air dual source heat pump water heater system for domestic water heating application. In the dual source system, an additional air source evaporator is introduced in parallel way based on a conventional direct expansion solar-assisted heat pump water heaters (DX-SHPWH) system, which can improve the performance of the DX-SHPWH system at a low solar radiation. In the present study, a dynamic mathematical model based on zoned lump parameter approach is developed to simulate the performance of the system (i.e. a modified DX-SHPWH (M-DX-SHPWH) system). Using the model, the performance of M-DX-SHPWH system is evaluated and then compared with that of the conventional DX-SHPWH system. The simulation results show the M-DX-SHPWH system has a better performance than that of the conventional DX-SHPWH system. At a low solar radiation of 100 W/m"2, the heating time of the M-DX-SHPWH decreases by 19.8% compared to the DX-SHPWH when water temperature reaches 55 °C. Meanwhile, the COP on average increases by 14.1%. In addition, the refrigerant mass flow rate distribution in the air source evaporator and the solar collector of the system, the allocation between the air source evaporator and the solar collector areas and effects of solar radiation and ambient air temperature on the system performance are discussed.

  19. Techno-economıc Analysıs of Evacuated Tube Solar Water Heater usıng F-chart Method

    Science.gov (United States)

    Fayaz, H.; Rahim, N. A.; Saidur, R.; Hasanuzzaman, M.

    2018-05-01

    Solar thermal utilization, especially the application of solar water heater technology, has developed rapidly in recent decades. Solar water heating systems based on thermal collector alone or connected with photovoltaic called as photovoltaic-thermal (PVT) are practical applications to replace the use of electrical water heaters but weather dependent performance of these systems is not linear. Therefore on the basis of short term or average weather conditions, accurate analysis of performance is quite difficult. The objective of this paper is to show thermal and economic analysis of evacuated tube collector solar water heaters. Analysis done by F-Chart shows that evacuated tube solar water heater achieves fraction value of 1 to fulfil hot water demand of 150liters and above per day for a family without any auxiliary energy usage. Evacuated tube solar water heater show life cycle savings of RM 5200. At water set temperature of 100°C, RM 12000 is achieved and highest life cycle savings of RM 6100 at the environmental temperature of 18°C are achieved. Best thermal and economic performance is obtained which results in reduction of household greenhouse gas emissions, reduction of energy consumption and saves money on energy bills.

  20. COMBINED UNCOVERED SHEET-AND-TUBE PVT-COLLECTOR SYSTEM WITH BUILT-IN STORAGE WATER HEATER

    Directory of Open Access Journals (Sweden)

    Muhammad Abid

    2012-02-01

    Full Text Available This work describes the design and investigation of a simple combined uncovered sheet-and-tube photo-voltaic-thermal (PVT collector system. The PVT-collector system consists of a support, standard PV module (1.22x0.305m, area=0.37m2, fill factor=0.75, sheet-and-tube water collector and storage tank-heater. The collector was fixed under PV module. Inclination angle of the PVT-collector to the horizontal plane was 45 degree. The storage tank-heater played double role i.e. for storage of hot water and for water heating. The PVT-collector system could work in the fixed and tracking modes of operation. During investigations of PVT-collector in natural conditions, solar irradiance, voltage and current of PV module, ambient temperature and water temperature in storage tank were measured. Average thermal and electrical powers of the PVT-collector system at the tracking mode of operation observed were 39W and 21W, with efficiencies of 15% and 8% respectively at the input power of 260W. The maximum temperature of the water obtained was 42oC. The system was observed efficient for low-temperature applications. The PVT-collector system may be used as a prototype for design of PVT-collector system for domestic application, teaching aid and for demonstration purposes.

  1. Experimental study on a prototype of heat pipe solar water heater using refrigerant R134a as a transfer fluid

    Science.gov (United States)

    Sitepu, T.; Sembiring, J.; Ambarita, H.

    2018-02-01

    A prototype of a solar water heater by using refrigerant as a heat transfer fluid is investigated experimentally. The objective is to explore the characteristics and the performance of the prototype. To make heat transfer from the collector to the heated fluid effectively, refrigerant R134a is used as a transfer. In the experiments, the initial pressure inside the heat pipe is varied. The prototype is exposed to solar irradiation in a location in Medan city for three days of the experiment. Solar collector temperatures, solar radiation, water temperature, and ambient temperature are measured. The efficiency of the system is analyzed. The results show that temperature of the hot water increases as the initial pressure of the working fluid increase. However, the increasing is not linear, and there must exist an optimum initial pressure. For the case with the refrigerant pressure of 110 psi, the maximum hot water temperature and maximum thermal efficiency are 45.36oC and 53.23%, respectively. The main conclusion can be drawn here is that solar water heater by using refrigerant R134a should be operated at initial pressure 110 psi.

  2. Experimental investigation of the higher coefficient of thermal performance for water-in-glass evacuated tube solar water heaters in China

    International Nuclear Information System (INIS)

    Zhang, Xinyu; You, Shijun; Xu, Wei; Wang, Min; He, Tao; Zheng, Xuejing

    2014-01-01

    Highlights: • The energy grades system for solar water heater (SWH) in China was introduced. • Heat loss and capacity of heat collection mainly affected SWH thermal performance. • Optimum ratio of tank volume to collector area for solar water heater is 57 to 72 L/m 2 . • The recommendation polyurethane insulation layer should be around 50 mm thick. • SWH with shorter tube has a better thermal performance. - Abstract: Solar water heaters (SWHs), now widely used in China, represent an environmentally friendly way to heat water. We tested the performance of more than 1000 water-in-glass evacuated tube SWHs according to Chinese standards and found that the heat loss from the storage tank and capacity of the solar collector affected their thermal performance. The optimum parameters to maximize the performance of water-in-glass evacuated tube SWHs included a ratio of tank volume to collector area of 57–72 L/m 2 , which should give a system efficiency of 0.49–0.57, meaning that the temperature of water in the tank will exceed 45 °C after one day of heat collection. In addition, the polyurethane insulation layer should be around 50 mm thick with a free foaming density of about 35 kg/m 3 , and the evacuated tube should be short. The tilt angle did not affect the performance of the SWHs. These results should aid in the design of highly efficient SWHs

  3. Artificial Neural Networks-Based Software for Measuring Heat Collection Rate and Heat Loss Coefficient of Water-in-Glass Evacuated Tube Solar Water Heaters

    Science.gov (United States)

    Liu, Zhijian; Liu, Kejun; Li, Hao; Zhang, Xinyu; Jin, Guangya; Cheng, Kewei

    2015-01-01

    Measurements of heat collection rate and heat loss coefficient are crucial for the evaluation of in service water-in-glass evacuated tube solar water heaters. However, conventional measurement requires expensive detection devices and undergoes a series of complicated procedures. To simplify the measurement and reduce the cost, software based on artificial neural networks for measuring heat collection rate and heat loss coefficient of water-in-glass evacuated tube solar water heaters was developed. Using multilayer feed-forward neural networks with back-propagation algorithm, we developed and tested our program on the basis of 915measuredsamples of water-in-glass evacuated tube solar water heaters. This artificial neural networks-based software program automatically obtained accurate heat collection rateand heat loss coefficient using simply "portable test instruments" acquired parameters, including tube length, number of tubes, tube center distance, heat water mass in tank, collector area, angle between tubes and ground and final temperature. Our results show that this software (on both personal computer and Android platforms) is efficient and convenient to predict the heat collection rate and heat loss coefficient due to it slow root mean square errors in prediction. The software now can be downloaded from http://t.cn/RLPKF08. PMID:26624613

  4. Artificial Neural Networks-Based Software for Measuring Heat Collection Rate and Heat Loss Coefficient of Water-in-Glass Evacuated Tube Solar Water Heaters.

    Science.gov (United States)

    Liu, Zhijian; Liu, Kejun; Li, Hao; Zhang, Xinyu; Jin, Guangya; Cheng, Kewei

    2015-01-01

    Measurements of heat collection rate and heat loss coefficient are crucial for the evaluation of in service water-in-glass evacuated tube solar water heaters. However, conventional measurement requires expensive detection devices and undergoes a series of complicated procedures. To simplify the measurement and reduce the cost, software based on artificial neural networks for measuring heat collection rate and heat loss coefficient of water-in-glass evacuated tube solar water heaters was developed. Using multilayer feed-forward neural networks with back-propagation algorithm, we developed and tested our program on the basis of 915 measured samples of water-in-glass evacuated tube solar water heaters. This artificial neural networks-based software program automatically obtained accurate heat collection rate and heat loss coefficient using simply "portable test instruments" acquired parameters, including tube length, number of tubes, tube center distance, heat water mass in tank, collector area, angle between tubes and ground and final temperature. Our results show that this software (on both personal computer and Android platforms) is efficient and convenient to predict the heat collection rate and heat loss coefficient due to it slow root mean square errors in prediction. The software now can be downloaded from http://t.cn/RLPKF08.

  5. Enhancing the solar still using immersion type water heater productivity and the effect of external cooling fan in winter

    International Nuclear Information System (INIS)

    Al-Garni, Ahmed Z.

    2012-01-01

    In the present work an attempt is made to enhance the of double slope solar still productivity by an immersion type water heater using. The effect of using an external fan to cool the glass surface is also examined. Experiments were carried out for winter season in Saudi Arabian climatic conditions at latitude 26 degree N. A solar still with 35 degree glass slope angle is chosen in our study. Since the yield of a solar still is more for low water depths, the water level in the base tank was maintained at 1 cm. The experimental results showed that the productivity increased by a significant 370% when two water heaters each having 500 W capacities was used. When external cooling fan was used the productivity was found to decrease by 4 % and 8% for wind speeds of 7 m/s and 9 m/s respectively. Thermal modeling was also done by the heat and mass transfer relations using, and then numerical simulations were carried out to validate with the experimental results. A good agreement between experimental and numerical results was found. The present study is partial implementation of two patents submitted in this field. (authors)

  6. Studies in biogas technology. Part 4. A noval biogas plant incorporating a solar water-heater and solar still

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, A K.N. [Indian Inst. of Science, Bangalore; Prasad, C R; Sathyanarayan, S R.C.; Rajabapaiah, P

    1979-09-01

    A reduction in the heat losses from the top of the gas holder of a biogas plant has been achieved by the simple device of a transparent cover. The heat losses thus prevented have been deployed to heat a water pond formed on the roof of the gas holder. This solar-heated water is mixed with the organic input for hot-charging of the biogas plant. To test whether the advantages indicated by a thermal analysis can be realized in practice, a biogas plant of the ASTRA design was modified to incorporate a roof-top water-heater. The operation of such a modified plant, even under worst case conditions, shows a significant improvement in the gas yield compared to the unmodified plant. Hence, the innovation reported here may lead to drastic reductions in the sizes and therefore costs of biogas plants. By making the transparent cover assume a tent-shape, the roof-top solar heater can serve the additional function of a solar still to yield distilled water. The biogas plant-cum-solar still described here is an example of a spatially integrated hybrid device which is extremely cost-effective.

  7. 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

  8. The Energy Efficiency of Hot Water Production by Gas Water Heaters with a Combustion Chamber Sealed with Respect to the Room

    Directory of Open Access Journals (Sweden)

    Grzegorz Czerski

    2014-08-01

    Full Text Available This paper presents investigative results of the energy efficiency of hot water production for sanitary uses by means of gas-fired water heaters with the combustion chamber sealed with respect to the room in single-family houses and multi-story buildings. Additionally, calculations were made of the influence of pre-heating the air for combustion in the chimney and air supply system on the energy efficiency of hot water production. CFD (Computational Fluid Dynamics software was used for calculation of the heat exchange in this kind of system. The studies and calculations have shown that the use of gas water heaters with a combustion chamber sealed with respect to the room significantly increases the efficiency of hot water production when compared to traditional heaters. It has also been proven that the pre-heating of combustion air in concentric chimney and air supply ducts essentially improves the energy efficiency of gas appliances for hot water production.

  9. On a Green Municipal Initiative in Cape Town (South Africa): Lessons from the Solar Water Heater Advanced Program

    International Nuclear Information System (INIS)

    Dubresson, Alain

    2013-01-01

    During the 2000's, the metropolitan municipality of Cape Town elaborated an ambitious energy transition strategy, backed up by the Energy and Climate Action Plan approved in 2010. One element of this plan is a mass solar water heater roll-out programme for households. Analysing the difficulties in the implementation of this programme, this article argues that the main limits to metropolitan action do not result primarily from local and/or multi-level governance issues but from national constraints and stakes which are deeply rooted in the political economy of South Africa. Any attempt to build an autonomous metropolitan energy policy is therefore today illusory in South Africa

  10. Effects of natural and synthetic soil conditioners on soil moisture ...

    African Journals Online (AJOL)

    The efficacy of a natural soil conditioner, Coco-Peat (C-P), and synthetic soil conditioners, Terawet (T-200) and Teraflow (T-F), in improving soil moisture content were examined on five Ghanaian soil series (Akroso, Akuse, Amo, Hake and Oyarifa). In general, the water retention of T-200 and C-P treated soils were similar ...

  11. A simulation study on the operating performance of a solar-air source heat pump water heater

    International Nuclear Information System (INIS)

    Xu Guoying; Zhang Xiaosong; Deng Shiming

    2006-01-01

    A simulation study on the operating performance of a new type of solar-air source heat pump water heater (SAS-HPWH) has been presented. The SAS-HPWH used a specially designed flat-plate heat collector/evaporator with spiral-finned tubes to obtain energy from both solar irradiation and ambient air for hot water heating. Using the meteorological data in Nanjing, China, the simulation results based on 150 L water heating capacity showed that such a SAS-HPWH can heat water up to 55 deg. C efficiently under various weather conditions all year around. In this simulation study, the influences of solar radiation, ambient temperature and compressor capacity on the performance of the SAS-HPWH were analyzed. In order to improve the overall operating performance, the use of a variable-capacity compressor has been proposed

  12. Retrofitting Domestic Hot Water Heaters for Solar Water Heating Systems in Single-Family Houses in a Cold Climate: A Theoretical Analysis

    Directory of Open Access Journals (Sweden)

    Björn Karlsson

    2012-10-01

    Full Text Available One of the biggest obstacles to economic profitability of solar water heating systems is the investment cost. Retrofitting existing domestic hot water heaters when a new solar hot water system is installed can reduce both the installation and material costs. In this study, retrofitting existing water heaters for solar water heating systems in Swedish single-family houses was theoretically investigated using the TRNSYS software. Four simulation models using forced circulation flow with different system configurations and control strategies were simulated and analysed in the study. A comparison with a standard solar thermal system was also presented based on the annual solar fraction. The simulation results indicate that the retrofitting configuration achieving the highest annual performance consists of a system where the existing tank is used as storage for the solar heat and a smaller tank with a heater is added in series to make sure that the required outlet temperature can be met. An external heat exchanger is used between the collector circuit and the existing tank. For this retrofitted system an annual solar fraction of 50.5% was achieved. A conventional solar thermal system using a standard solar tank achieves a comparable performance for the same total storage volume, collector area and reference conditions.

  13. China's transition to green energy systems: The economics of home solar water heaters and their popularization in Dezhou city

    International Nuclear Information System (INIS)

    Li Wei; Song Guojun; Beresford, Melanie; Ma, Ben

    2011-01-01

    Studying the popularization of solar water heaters (SWHs) is significant for understanding China's transition to green energy systems. Using Dezhou as a case study, this paper presents new angles on analyzing SWH deployment in China by addressing both the economic potential and the institutional dimensions at the local level. Using estimates from the demand-side of hot water for a typical three-person household in Dezhou, the paper evaluates the economic potential of a SWH in saving electricity and reducing carbon dioxide emissions. Then, expanding the analysis beyond economics, we take an institutionalist approach to study the institutional factors that contribute to Dezhou's success in SWH adoptions. By examining the five main actors in Dezhou's energy regime, we find that Dezhou's SWH deployment is driven by an urge to develop businesses and the local economy, and its success results from at least five unique factors, including the development of SWH industrial clusters in Dezhou, big manufacturers' market leadership in SWH innovations, a tight private enterprise-local government relation, geographic location within the SWH industrial belt, and the adaptive attitude of Dezhou's households towards natural resource scarcity. - Highlights: → We study the popularization of solar water heaters in Dezhou, China. → We study the institutional factors that contribute to Dezhou's success. → Five main actors in Dezhou's energy regime are examined. → Dezhou's success results from at least five unique factors. → This leads to important directions for improving China'ss green innovation adoption.

  14. Experimental study on depth of paraffin wax over floating absorber plate in built-in storage solar water heater

    Directory of Open Access Journals (Sweden)

    R Sivakumar

    2015-11-01

    Full Text Available The aim of this article is to study the effect of depth of phase change material over the absorber surface of an integrated collector-storage type flat plate solar water heater. Flat plate solar water heaters are extensively used all over the world to utilize the natural source of solar energy. In order to utilize the solar energy during off-sunshine hours, it is inevitable to store and retain solar thermal energy as long as possible. Here, phase change material is not used for heat storage, but to minimize losses during day and night time only. The depth of phase change material over a fixed depth of water in a solar thermal collector is an important geometric parameter that influences the maximum temperature rise during peak solar irradiation and hence the losses. From the results of the studies for different masses of paraffin wax phase change material layers, the optimum depth corresponding to the maximum heat gain till evening is found to be 2 mm, and the heat retention till the next day morning is found to be 4 mm.

  15. Infrared Heaters

    Science.gov (United States)

    1979-01-01

    The heating units shown in the accompanying photos are Panelbloc infrared heaters, energy savers which burn little fuel in relation to their effective heat output. Produced by Bettcher Manufacturing Corporation, Cleveland, Ohio, Panelblocs are applicable to industrial or other facilities which have ceilings more than 12 feet high, such as those pictured: at left the Bare Hills Tennis Club, Baltimore, Maryland and at right, CVA Lincoln- Mercury, Gaithersburg, Maryland. The heaters are mounted high above the floor and they radiate infrared energy downward. Panelblocs do not waste energy by warming the surrounding air. Instead, they beam invisible heat rays directly to objects which absorb the radiation- people, floors, machinery and other plant equipment. All these objects in turn re-radiate the energy to the air. A key element in the Panelbloc design is a coating applied to the aluminized steel outer surface of the heater. This coating must be corrosion resistant at high temperatures and it must have high "emissivity"-the ability of a surface to emit radiant energy. The Bettcher company formerly used a porcelain coating, but it caused a production problem. Bettcher did not have the capability to apply the material in its own plant, so the heaters had to be shipped out of state for porcelainizing, which entailed extra cost. Bettcher sought a coating which could meet the specifications yet be applied in its own facilities. The company asked The Knowledge Availability Systems Center, Pittsburgh, Pennsylvania, a NASA Industrial Applications Center (IAC), for a search of NASA's files

  16. Experimental Study of a Thermosyphon Solar Water Heater Coupled to a Fibre-Reinforced Plastic (FRP) Storage Tank

    International Nuclear Information System (INIS)

    Nwosu, P. N.; Oparaku, O. U.; Okonkwo, W. I.; Unachukwu, G. O.; Agbiogwu, D.

    2011-01-01

    The thermal performance of the thermosyphon solar water heater was analyzed to show its applicability in a tropical climate using data of cloudy, sunny and hazy days. The average daily efficiency of the parallel-connected module, ranged between 35 and 40%. Also, an analysis of the temperature storage characteristics of a novel fibre-reinforced plastic (FRP) storage tank was undertaken. The inlet andoutlet positions were determined using the recommendation of Simon and Wenxian [1]: the optional position for the inlet/outlet was around the very top/bottom of the tank. The obtained results showed that the coupled FRP tank substantially retained and delivered the stored hot water during off-sunshine hours with minimal losses, and stratification occurred in the tank as a result. In view of the thermal performance, FRP materials can be efficiently employed in the design of solar hot water storage tanks. (authors)

  17. Numerical study on the effects of absorptivity on performance of flat plate solar collector of a water heater

    Science.gov (United States)

    Tambunan, D. R. S.; Sibagariang, Y. P.; Ambarita, H.; Napitupulu, F. H.; Kawai, H.

    2018-03-01

    The characteristics of absorber plate of a flat plate solar collector play an important role in the improvement of the performance. In this work, a numerical analysis is carried out to explore the effect of absorptivity and emissivity of absorber plate to the performance of the solar collector of a solar water heater. For a results comparison, a simple a simple solar box cooker with absorber area of 0.835 m × 0.835 m is designed and fabricated. It is employed to heat water in a container by exposing to the solar radiation in Medan city of Indonesia. The transient governing equations are developed. The governing equations are discretized and solved using the forward time step marching technique. The results reveal that the experimental and numerical results show good agreement. The absorptivity of the plate absorber and emissivity of the glass cover strongly affect the performance of the solar collector.

  18. Cardio-Muscular Conditioner

    Science.gov (United States)

    1993-01-01

    In the mid-sixties, Gary Graham, a Boeing designer, developed a cardiovascular conditioner for a planned Air Force orbiting laboratory. After the project was cancelled, Graham participated in space station conditioning studies for the Skylab program. Twenty years later, he used this expertise to develop the Shuttle 2000-1, a physical therapy and athletic development conditioner, available through Contemporary Designs. The machine is used by football teams, sports clinics and medical rehabilitation centers. Cardiovascular fitness and muscular strength development are promoted through both kinetic and plyometric exercises.

  19. Assessment of global environmental impacts by utilizing methodology of LCA on solar water heater for dwellings; LCA shuho ni yoru taiyonetsu onsuiki no kankyo fuka hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Kamoshida, J [Shibaura Institute of Technology, Tokyo (Japan); Asai, S [Yazaki Corp., Tokyo (Japan)

    1997-11-25

    CO2 emission was quantified through the life cycle of a solar water heater to assess its environment impact. Although LCA (life cycle assessment) originally sums up I/O of all materials and energy through the whole life cycle of a product to examine environment impact, this assessment was carried out for only CO2. Calculation of CO2 emission assumed a natural circulating solar water heater of 200 l in effective hot water capacity, 2.78m{sup 2} in effective collecting area, and 0.5 in average annual collecting efficiency of total solar radiation, and an auxiliary city gas heat source for compensating insufficient heat quantity. The total CO2 emission in the life cycle of a solar water heater was obtained from an industrial association table assuming the life cycles of 10 and 20 years. CO2 emission was estimated to be 5407.1kg-CO2 and 10665.2kg-CO2 for 10 and 20 years, respectively. CO2 emission due to city gas was largest in the total CO2 emission in the life cycle. As a result, for reduction of CO2 emission due to a solar water heater, improvement of equipment efficiency was most important. 6 refs., 5 figs., 3 tabs.

  20. A hybrid desalination system using humidification-dehumidification and solar stills integrated with evacuated solar water heater

    International Nuclear Information System (INIS)

    Sharshir, S.W.; Peng, Guilong; Yang, Nuo; Eltawil, Mohamed A.; Ali, Mohamed Kamal Ahmed; Kabeel, A.E.

    2016-01-01

    Highlights: • Evacuated solar water heater integrated with humidification-dehumidification system. • Reuse of warm water drained from humidification-dehumidification to feed solar stills. • The thermal performance of hybrid system is increased by 50% and maximum yield is 63.3 kg/day. • The estimated price of the freshwater produced from the hybrid system is $0.034/L. - Abstract: This paper offers a hybrid solar desalination system comprising a humidification-dehumidification and four solar stills. The developed hybrid desalination system reuses the drain warm water from humidification-dehumidification to feed solar stills to stop the massive warm water loss during desalination. Reusing the drain warm water increases the gain output ratio of the system by 50% and also increased the efficiency of single solar still to about 90%. Furthermore, the production of a single solar still as a part of the hybrid system was more than that of the conventional one by approximately 200%. The daily water production of the conventional one, single solar still, four solar still, humidification- dehumidification and hybrid system were 3.2, 10.5, 42, 24.3 and 66.3 kg/day, respectively. Furthermore, the cost per unit liter of distillate from conventional one, humidification- dehumidification and hybrid system were around $0.049, $0.058 and $0.034, respectively.

  1. Forced-circulation solar water heater using a solar battery; Taiyo denchi wo mochiita kyosei junkanshiki taiyonetsu onsuiki

    Energy Technology Data Exchange (ETDEWEB)

    Asai, S; Mizuno, T [Yazaki Resources Co. Ltd., Shizuoka (Japan)

    1996-10-27

    For the purpose of satisfying demands for qualitative improvement on tapwater temperature and pressure, an indirect-type solar water heater using solar cells, in which a closed type hot water storage tank connected directly to the water supply is integrated with a solar collector, was examined for its characteristics and performance. The heat collecting medium is a water solution of polypropylene glycol, which circulates through the solar collector pump, cistern, solar collector, and heat exchanger (hot water storage tank). The results of the test are summarized below. When comparison is made between the two solar collector pump control methods, the solar cells direct connection method and the differential thermo method utilizing temperature difference between the solar collector and the hot water storage tank, they are alike in collecting heat on clear days, but on cloudy days the latter collects 5% more than the former. In winter, when the heat exchanger heat transfer area is 0.4m{sup 2} large, a further increase in the area improves but a little the heat collecting efficiency. An increase in the medium flow rate and temperature, or in the Reynolds number, enhances the heat collecting efficiency. 13 figs., 6 tabs.

  2. An economic and performance design study of solar preheaters for domestic hot water heaters in North Carolina

    Science.gov (United States)

    Jones, C. B.; Smetana, F. O.

    1977-01-01

    The performance and estimated material costs for several solar preheaters for domestic hot water heaters using isolation levels present in North Carolina are presented. The effects of monthly variations in isolation and the direction of incident radiation are included. Demand is assumed at 13 gallons (49.2 liters) per day per person. The study shows that a closed circulation system with 82 gallons (310 liters) of preheated storage and 53.4 cu ft (4.94 cu m) of collector surface with single cover can be expected to cost about $800 and to repay it capital cost and interest (at 8%) in 5.2 years, assuming present electric rates increase at 5% per year.

  3. A novel PV/T-air dual source heat pump water heater system: Dynamic simulation and performance characterization

    International Nuclear Information System (INIS)

    Cai, Jingyong; Ji, Jie; Wang, Yunyun; Zhou, Fan; Yu, Bendong

    2017-01-01

    Highlights: • The PV/T evaporator and air source evaporator connect in parallel and operate simultaneously. • A dynamic model is developed to simulate the behavior of the system. • The thermal and electrical characteristics of the PV/T evaporator are evaluated. • The contribution of the air source evaporator and PV/T evaporator has been discussed. - Abstract: To enable the heat pump water heater maintain efficient operation under diverse circumstances, a novel PV/T-air dual source heat pump water heater (PV/T-AHPWH) has been proposed in this study. In the PV/T-AHPWH system, a PV/T evaporator and an air source evaporator connect in parallel and operate simultaneously to recover energy from both solar energy and environment. A dynamic model is presented to simulate the behavior of the PV/T-AHPWH system. On this basis, the influences of solar irradiation, ambient temperature and packing factor have been discussed, and the contributions of air source evaporator and PV/T evaporator are evaluated. The results reveal that the system can obtain efficient operation with the average COP above 2.0 under the ambient temperature of 10 °C and solar irradiation of 100 W/m 2 . The PV/T evaporator can compensate for the performance degradation of the air source evaporator caused by the increasing condensing temperature. As the evaporating capacity in PV/T evaporator remains at relatively low level under low irradiation, the air source evaporator can play the main role of recovering heat. Comparing the performance of dual source heat pump system employing PV/T collector with that utilizing normal solar thermal collector, the system utilizing PV/T evaporator is more efficient in energy saving and performance improvement.

  4. 14 CFR 29.859 - Combustion heater fire protection.

    Science.gov (United States)

    2010-01-01

    ... relief of any backfire that, if so restricted, could cause heater failure. (d) Heater controls; general. There must be means to prevent the hazardous accumulation of water or ice on or in any heater control... malfunctioning; or (ii) Allow flammable fluids or vapors to reach the heater in case of leakage. (2) Each part of...

  5. Application of CAE-modeling for the study of the influence of the sensor location on the flow-through water heater operation

    Science.gov (United States)

    Yakunin, A. G.

    2018-01-01

    The article deals with issues related to increasing the efficiency of the system of automatic maintenance of the temperature of liquid media entering the pipes to the place of consumption. For this purpose, a flowing water heater model is proposed, made in the SolidWorks environment, the construction parameters of which can be changed using the appropriate macro and screen form. It is shown that the choice of the location of the temperature sensor has a significant effect on such parameters of the device as the accuracy of maintaining a given temperature regime and the duration of the transient process caused by a change in the temperature of the liquid entering the heater. On a concrete example, it is shown that by changing the distance between the sensor and the heating module, it is possible to achieve minimum temperature fluctuations of the heat-transfer-agent at the heater outlet.

  6. 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.

  7. 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.

  8. Extreme learning machine: a new alternative for measuring heat collection rate and heat loss coefficient of water-in-glass evacuated tube solar water heaters.

    Science.gov (United States)

    Liu, Zhijian; Li, Hao; Tang, Xindong; Zhang, Xinyu; Lin, Fan; Cheng, Kewei

    2016-01-01

    Heat collection rate and heat loss coefficient are crucial indicators for the evaluation of in service water-in-glass evacuated tube solar water heaters. However, the direct determination requires complex detection devices and a series of standard experiments, wasting too much time and manpower. To address this problem, we previously used artificial neural networks and support vector machine to develop precise knowledge-based models for predicting the heat collection rates and heat loss coefficients of water-in-glass evacuated tube solar water heaters, setting the properties measured by "portable test instruments" as the independent variables. A robust software for determination was also developed. However, in previous results, the prediction accuracy of heat loss coefficients can still be improved compared to those of heat collection rates. Also, in practical applications, even a small reduction in root mean square errors (RMSEs) can sometimes significantly improve the evaluation and business processes. As a further study, in this short report, we show that using a novel and fast machine learning algorithm-extreme learning machine can generate better predicted results for heat loss coefficient, which reduces the average RMSEs to 0.67 in testing.

  9. Efecto de acondicionadores naturales y sintéticos sobre los cationes solubles y la infiltración del agua en un Aridisol Effect of natural and synthetic conditioners on soluble cations and water infiltration in an Aridisol

    Directory of Open Access Journals (Sweden)

    Manuel Henríquez

    2003-02-01

    Full Text Available El objetivo del trabajo fue evaluar el efecto de diversos acondicionadores sobre los cationes solubles y la infiltración del agua en un suelo Vertic Haplocambid, arcilloso muy fino, de la depresión de Quibor, Venezuela. Fueron aplicadas soluciones de acondicionadores naturales de cardón dato (Lemaireocereus griceus (Haw. Br. & Rose y de cardón lefaria (Cereus deficiens Otto & Dietr, a concentraciones de2.000, 1.000 y 500 mg L-1, solución de un acondicionador sintético, la poliacrilamida, en concentración de 10 mg L-1 y agua del acueducto local. Las soluciones de cada uno de esos tratamientos fueron vertidas sobre mini canales rellenos del suelo, para simular el flujo del agua en surcos. Los acondicionadores naturales incrementaron la infiltración y produjeron una relación Ca-Mg-Na en el suelo, mas adecuada que la producida con la aplicación de la poliacrilamida o el agua sin aditivos.The objective of this work was to evaluate the effect of several conditioners on soluble cations and water infiltration on a fine clay Vertic Haplocambid soil collected on the Quibor depression, Venezuela. Solutions of two natural conditioners from dato cactus (Lemaireocereus griceus (Haw. Br. & Rose and lefaria cactus(Cereus deficiens Otto & Dietr, on concentrations of 2,000, 1,000 and 500 mg L-1, a synthetic polyacrilamide conditioner solution of 10 mg L-1 and local tap water were applied to the soil. All solutions and the tap water were poured in a mini flume to simulate the irrigation process on furrows. The natural conditioners increased the infiltration and produced a better Ca-Mg-Na relationship as compared with that produced by the polyacrilamide and the tap water without additives.

  10. Microbial induced corrosion (MIC) on DHP copper by Desulfovibrio desulfuricans and Bacillus megaterium strains in media simulating heater waters

    International Nuclear Information System (INIS)

    Zumelzu, E.; Cabezas, C.; Schoebitz, R.; Ugarte, R.; Rodriguez, E.D.; Rios, J.

    2003-01-01

    The complexity and diversity of microbial populations in water heating systems of steam generators make it necessary to study the magnitude of the metabolic activity of bacteria and biofilm development that may lead to degradation of metal components through microbial induced corrosion (MIC). Electrolytes simulating the conditions found in heater water networks were used to induce biofilm formation on DHP copper coupons by Desulfovibrio desulfuricans DSMZ and Bacillus megaterium C10, a commercial strain and an isolate from these waters, respectively. In order to enhance their action, industrial waters enriched with the minimum nutrient content such as sodium lactate and sodium sulphite for the DSMZ strain and glucose, proteose peptone and starch for the C10 strain were employed. Biofilm formation was studied under controlled temperature, time, shaking, pH and concentrations of the media used in this study. Then, the samples were electrochemically tested in an artificial solution of sea water as control medium, based on the hypothesis that the action of an aggressive biofilm/electrolyte medium generates damaged and non-damaged areas on the metal surface, and assuming that the sea water trial can detect the latter. Hence, a higher anodic current was associated with a lower degradation of the metal surface by the action of one of the media under study. All these trials were performed along with bacterial count, scanning electron microscopy (SEM) and atomic absorption spectroscopy (AAS). Furthermore, it was possible to identify under which conditions MIC on DHP copper occurred and complex mechanisms from retention of cations to diffusion processes at the biofilm/tested media interface level were proposed. Surface corrosion by MIC took place on DHP copper; therefore, greater control on the treatment of industrial waters is highly desirable. (author)

  11. Desempenho de um aquecedor de água a biogás Performance of a water heater by biogas

    Directory of Open Access Journals (Sweden)

    Fabio M. da Silva

    2005-12-01

    Full Text Available Estudos foram desenvolvidos para dimensionar e adaptar o injetor do queimador principal de um aquecedor de água tipo acumulação de 75 L. O diâmetro do injetor foi redimensionado em função da pressão de serviço de 100 mm H2O e poder calorífico inferior do biogás de 21.600 kJ m-3 n, garantindo a manutenção da potência calorífica do equipamento de 20.900 kJ h-1. Os resultados demonstraram que o queimador adaptado operou com biogás adequadamente, com chama estável. A eficiência média do aquecedor foi de 68%, para ganho térmico de 36,7 ºC, correspondendo à temperatura final da água igual a 62,7 ºC, sendo consumido 0,796 m³n de biogás, aquecendo 75 L de água em 72 minutos.Studies had been developed to project and to adapt the injector of the main burner of water heater accumulated type of 75 L. The diameter of the injector was project in function of the pressure of service of 100 mm H2O and inferior calorific power of biogas of 21,600 kJ m-3 n, having guaranteed the maintenance of the calorific power of the equipment of 20,900 of kJ h-1 .The results had demonstrated that the adapted burner to operate with biogas operated adequately with a steady flame. The average efficiency of the heater was of 68%, for a thermal profit of 36.7 ºC, corresponding the final temperature of the water of 62.7 ºC being consumed 0.796 m³ n of biogas, heating 75 L of water in 72 minutes.

  12. Forced-circulation solar water heater using a solar battery; Taiyo denchi wo mochiita kyosei junkahshiki taiyonetsu onsuiki

    Energy Technology Data Exchange (ETDEWEB)

    Asai, S; Mizuno, T [Yazaki Corp., Tokyo (Japan)

    1997-11-25

    Optimal operation control was discussed on a forced-circulation solar water heater using solar cells not only as the power supply of a heat collecting pump, but also for controlling operation of the heat collecting pump. With this system, when the amount of power generated by solar cells reaches a sufficient level for operating the heat collecting pump, the heat collecting pump starts operation, wherein the heat collecting medium circulates in the system. The discussion was given by using simulation based on experimental expressions such as the relation expression between insolation and heat collecting medium flow rate as derived from the result of the system`s heat collecting performance test. As a result, the following conclusions were obtained: optimal insolation for activating the discussed system is from 50 to 100 W/m {sup 2}, and the heat collected within this range is within -1.5% of the collected heat amount at an optimum value; optimal activating insolation for the case of 1000 to 2000 W/m {sup 2} with low daily cumulative insolation is from 0 to 50 W/m {sup 2}, whereas the optimal activating insolation amount increases as the daily cumulative insolation amount increases; and the optimal activating insolation amount increases as water to be supplied requires higher temperature. 1 ref., 17 figs., 2 tabs.

  13. The design of electrical heater pins to simulate transient dryout and post-dryout of water reactor fuel

    International Nuclear Information System (INIS)

    Burgess, M.H.; Butcher, A.A.; Sidoli, J.E.A.

    1978-11-01

    A theoretical assessment of indirect and direct filled heater simulations of nuclear reactor fuel pins is described. For reasons of fast temperature response, a direct unfilled heater, with thermocouples buried in the walls, is recommended for studies of Loss-of-Coolant Accidents leading to dryout, post-dryout and rewetting. A design of heater pins, for use in SGHWR or PWR experiments, and compatible with existing 9MW power supplies, is described. Experiments to confirm collapse pressure calculations at 1000 0 C and thermocouple response times are also reported. (author)

  14. Test of two heat-pump systems, Fre-Heater Type B and Fre-Heater Type C, made by Mueller. Installations for the cooling of milk and the heating of water on farms. Beproeving van twee warmtepompsystemen, type Fre-Heater, modellen B en C, fabrikaat Mueller. Installaties voor het koelen van melk en het verwarmen van water op de boerderij

    Energy Technology Data Exchange (ETDEWEB)

    Bouman, S; Verheij, C P; de Vries, J

    1980-01-01

    At the request of Meko Holland BV, Assen (the Netherlands), two heat-pump systems, Fre-Heater Type B and Fre-Heater Type C (FH-B and FH-C), were tested for their suitability for the simultaneous cooling of milk and heating of water on farms. The main purpose of the tests was to provide information about the technical properties of the systems, and about the possibilities they offer for the saving of energy. The test was carried out according to the directives laid down in the 'Beproevingsmethoden voor warmtepompsystemen ten behoeve van het verwarmen van water op de boerderij' (Test methods for heat-pump systems for the heating of water on farms), issued by the Netherlands Institute for Dairy Research, 1980. Both systems were compared with a conventional air-cooled refrigerated farm milk tank with a COPR (coefficient of performance of refrigeration) of 2.5. The FH-B was found to have a COPR of 2.25, and the FH-C a COPR of 2.52. The net savings of energy that could be achieved with the FH-B were 16.8 kWh per m3 cooled 'milk', and with the FH-C 17.2 kWh per m3 cooled 'milk'. Based on a pay-back period of five years and a price of electrical energy of Dfl 0.20 per kWh, the FH-B appeared to be economically justified at a farm with 38 cows and the FH-C at a farm with 48 cows (milk production 5.5 m3 per cow per year).

  15. Ventilating Air-Conditioner

    Science.gov (United States)

    Dinh, Khanh

    1994-01-01

    Air-conditioner provides ventilation designed to be used alone or incorporated into cooling or heating system operates efficiently only by recirculating stale air within building. Energy needed to operate overall ventilating cooling or heating system slightly greater than operating nonventilating cooling or heating system. Helps to preserve energy efficiency while satisfying need for increased forced ventilation to prevent accumulation of undesired gases like radon and formaldehyde. Provides fresh treated air to variety of confined spaces: hospital surgeries, laboratories, clean rooms, and printing shops and other places where solvents used. In mobile homes and portable classrooms, eliminates irritant chemicals exuded by carpets, panels, and other materials, ensuring healthy indoor environment for occupants.

  16. Determination of inorganic compounds in drinking water on the basis of house water heater scale, part 1: Determination of heavy metals and uranium

    Directory of Open Access Journals (Sweden)

    Rajković Miloš B.

    2004-01-01

    Full Text Available The analysis of scale originated from drinking water on the house water heater, showed that scale is basically calcium carbonate that crystallizes hexagonally in the form of calcite. Scale taken as a sample from different spots in Belgrade – upper town of Zemun (sample 1 and Pančevo (sample 2 showed different configuration although it came from the same waterworks. That indicates either that the water flowing through waterworks pipes in different parts of the city is not the same or the waterworks net is not the same (age, maintaining, etc. All the elements which are dominant in drinking water (Ca, Mg, K, and Na, and which could be found in water by natural processes, are by their content far below the values regulated by law. The analysis also showed the presence of many metals: Ti, Pb, Zn, Cu Li, Sr, Cd, and Cr in the first sample, which are not found in the scale taken near Pančevo. The results obtained by calculating the mass concentration in drinking water on the basis of scale content, showed that both waters belonged to the category of low mineral waters. Contents of inorganic substances in these waters (117.85 mg/dm3 for sample 1 or 80.83 mg/dm3 for sample 2 are twice lower than the values predicted by the legislation. Gammaspectrometric analysis indicates the presence of radioactive elements – uranium and strontium which can influence human health.

  17. Experimental Study of a Novel Direct-Expansion Variable Frequency Finned Solar/Air-Assisted Heat Pump Water Heater

    Directory of Open Access Journals (Sweden)

    Jing Qin

    2018-01-01

    Full Text Available A novel direct expansion variable frequency finned solar/air-assisted heat pump water heater was fabricated and tested in the enthalpy difference lab with a solar simulator. A solar/air source evaporator-collector with an automatic lifting glass cover plate was installed on the system. The system could be operated in three modes, namely, air, solar, and dual modes. The effects of the ambient temperature, solar irradiation, compressor frequency, and operating mode on the performance of this system were studied in this paper. The experimental results show that the ambient temperature, solar irradiation, and operating mode almost have no effect on the energy consumption of the compressor. When the ambient temperature and the solar irradiation were increased, the COP was found to increase with decreasing heating time. Also, when the compressor frequency was increased, an increase in the energy consumption of the compressor and the heat gain of the evaporator were noted with a decrease in the heating time.

  18. Performance enhancement studies in a thermosyphon flat plate solar water heater with CuO nanofluid

    Directory of Open Access Journals (Sweden)

    Dasaien Anin Vincely

    2017-01-01

    Full Text Available Experiments were conducted on a thermosyphon type flat plate collector, inclined at 45°, for water heating application. Water and water based nanofluids were used as absorber fluid to gain heat from solar rays incident on the flat plate col-lector. Nanofluids were prepared by adding CuO nanoparticles of 40-50 nm size to the base fluid at 0.1, 0.2, 0.3, and 0.5 wt% (ζ. The hot absorber fluid was made to circulate in the shell side of a heat exchanger, placed at the top of the flat plate collector, where utility water was circulated inside a helically coiled Cu tube. Temperatures at strategic locations in the flat plate collector, working fluid, utility water inlet and outlet were measured. The nanofluid increases the collector efficiency with increasing ζ. A highest efficiency enhancement of 5.7% was observed for the nanofluid with ζ = 0.2 having a mass flow rate of 0.0033 kg/s. The 3-D, steady-state, conjugate heat transfer CFD analyses were carried out using the ANSYS FLUENT 15.0 software. Theoretically estimated buoyancy induced fluid flow rates were close with the CFD predictions and thus validates the computational methodology.

  19. State-of-the-art report for solar water heaters in the Netherlands 2008

    International Nuclear Information System (INIS)

    Bosselaar, L.; Blezer, I.

    2009-01-01

    This state-of-the-art report addresses the implementation of solar heat in the Netherlands. The main appliance is the solar boiler for production of warm tap water in households. Other appliances are production of warm tap water in large buildings (e.g. homes for the elderly), heating of dwellings and heating of swimming pools. The aim of this report is to provide an overview of the market and techniques for this technology. Emphasis will be put on solar boilers, but other appliances will also be addressed [nl

  20. Effect of Tank Size on the Temperature Distributions for Hybrid Photovoltaic/Thermal Water Heaters

    OpenAIRE

    Al-Masri, Ahmad

    2016-01-01

    In the present study an investigation was conducted on the temperature distribution effect for several tank capacities (100 L, 120 L, 150 L and 200 L) having two different aspect ratios (H/D) for each capacity. Hot water is supplied to these tanks by a Hybrid PV/T collector of 4 m² illuminating area. The circulation of water within PV cells cools its surface area to solve the problem occurred in PV cells, where each 1°C increase in the surface module 0.45% of the electrical efficiency decreas...

  1. Solar Energy in China: Development Trends for Solar Water Heaters and Photovoltaics in the Urban Environment

    Science.gov (United States)

    Wallace, William; Wang, Zhongying

    2006-01-01

    China is the world's largest market for solar water heating systems, installing 13 million square meters of new systems in 2004, mostly in large cities. Municipal authorities, however, are sensitive to quality and visual impact issues created by this technology deployment. Therefore, there is currently a trend toward developing building integrated…

  2. The sun as hot water source. Answers to questions on the solar water heater; Le soleil source d'eau chaude. Les reponses a vos questions sur le chauffe-eau solaire

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This guide answers to the main questions concerning a water heating system for domestic use. It aims to help the people who want to buy a solar water heater, to better estimate the advantages and the limits, in providing information on the operating and the use. (A.L.B.)

  3. A procedure for analysing energy savings in multiple small solar water heaters installed in low-income housing in Brazil

    International Nuclear Information System (INIS)

    Giglio, Thalita; Lamberts, Roberto; Barbosa, Miriam; Urbano, Mariana

    2014-01-01

    Due to government subsidies, Brazil has witnessed an increase in the installation and use of small solar water heating systems in low-income housing projects. Although the initiative has reduced the load curve during peak times due to the reduced use of electric showerheads, measurement and verification (M and V) are needed to validate the savings. M and V procedures should take into account the social and economic variability of low-income housing developments. To improve M and V in low-income housing projects, this paper presents a methodology for identifying homogeneous subgroups based on their energy-saving potential. This research strategy involved a cluster analysis designed to improve the understanding of what energy savers and other influencing factors exist. A case study in Londrina Brazil was undertaken with 200 low-income families. Five clusters, created based on savings potential, were defined. The results showed that only two clusters demonstrated good electricity savings, representing 47% of families. However, two clusters, or 37%, did not provide satisfactory savings, and the other 16% did not provide any consumption history due to previous use of illegal city electricity connection practices. Therefore, studies confirm the need for a detailed measurement of the representative subgroups to assess the influence of human behaviour on potential SWHS-induced savings. - Highlights: • M and V is necessary to improve solar collector-area-based subsidy programmes. • M and V in large-scale sample should contemplate the social and economic variability. • Samples with homogeneous subgroups contribute to a consistent energy-saving M and V. • Solar Water Heaters in some cases may not offer energy saving in a low-income context. • SWH performance decreases with low educational level and difficulty of operation

  4. Artificial neural networks for the performance prediction of heat pump hot water heaters

    Science.gov (United States)

    Mathioulakis, E.; Panaras, G.; Belessiotis, V.

    2018-02-01

    The rapid progression in the use of heat pumps, due to the decrease in the equipment cost, together with the favourable economics of the consumed electrical energy, has been combined with the wide dissemination of air-to-water heat pumps (AWHPs) in the residential sector. The entrance of the respective systems in the commercial sector has made important the modelling of the processes. In this work, the suitability of artificial neural networks (ANN) in the modelling of AWHPs is investigated. The ambient air temperature in the evaporator inlet and the water temperature in the condenser inlet have been selected as the input variables; energy performance indices and quantities characterising the operation of the system have been selected as output variables. The results verify that the, easy-to-implement, trained ANN can represent an effective tool for the prediction of the AWHP performance in various operation conditions and the parametrical investigation of their behaviour.

  5. A semi-analytical refrigeration cycle modelling approach for a heat pump hot water heater

    Science.gov (United States)

    Panaras, G.; Mathioulakis, E.; Belessiotis, V.

    2018-04-01

    The use of heat pump systems in applications like the production of hot water or space heating makes important the modelling of the processes for the evaluation of the performance of existing systems, as well as for design purposes. The proposed semi-analytical model offers the opportunity to estimate the performance of a heat pump system producing hot water, without using detailed geometrical or any performance data. This is important, as for many commercial systems the type and characteristics of the involved subcomponents can hardly be detected, thus not allowing the implementation of more analytical approaches or the exploitation of the manufacturers' catalogue performance data. The analysis copes with the issues related with the development of the models of the subcomponents involved in the studied system. Issues not discussed thoroughly in the existing literature, as the refrigerant mass inventory in the case an accumulator is present, are examined effectively.

  6. 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.

  7. PERFORMANCE CHARACTERISTICS OF PARABOLIC SOLAR COLLECTOR WATER HEATER SYSTEM FITTED WITH NAIL TWISTED TAPES ABSORBER

    Directory of Open Access Journals (Sweden)

    K. SYED JAFAR

    2017-03-01

    Full Text Available In this paper, the experimental heat transfer, friction loss and thermal performance data for water flowing through the absorber tube fitted with two different twisted tape configurations in parabolic trough collector (PTC are presented. In the present work, a relative experimental study is carried out to investigate the performance of a PTC influenced by heat transfer through fluidabsorber wall mixing mechanism. The major findings of this experiment show that heat transport enhancement in the nail twisted tape collector perform significantly better than plain twisted tapes and also show that the smallest twisted tape ratio enhances the system performance remarkably maximizing the collector efficiency. The results suggest that the twisted tape and nail twisted tape would be a better option for high thermal energy collection in laminar region of the PTC system.

  8. Comparison of two temperature control techniques in a forced water heater solar system

    Science.gov (United States)

    Hernández, E.; E Guzmán, R.; Santos, A.; Cordoba, E.

    2017-12-01

    a study on the performance of a forced solar heating system in which a comparative analysis of two control strategies, including the classic on-off control and PID control is presented. From the experimental results it was found that the two control strategies show a similar behaviour in the solar heating system forced an approximate settling time of 60 min and over-elongation 2°C for the two control strategies. Furthermore, the maximum temperature in the storage tank was 46°C and the maximum efficiency of flat plate collector was 76.7% given that this efficiency is the ratio of the energy of the radiation on the collector and the energy used to heat water. The efficiency obtained is a fact well accepted because the business efficiencies of flat plate collectors are approximately 70%.

  9. ANALISIS TERMAL KOLEKTOR SURYA TIPE PLAT DATAR DENGAN FLUIDA KERJA ETANOL 96% PADA SISTEM SOLAR WATER HEATER

    Directory of Open Access Journals (Sweden)

    Rianda .

    2017-12-01

    Full Text Available Abstrak – Optimasi penggunaan energi matahari perlu ditingkatkan, salah satunya dengan menggunakan kolektor surya. Panas yang diterima digunakan sebagai sumber kalor untuk memanaskan etanol 96% sebagai fluida kerja pada sistem solar water heater (SWH. Kegiatan penelitian diawali dengan desain, kontruksi, dan pengujian termal kolektor surya tipe plat datar. tujuan penelitian makalah adalah untuk menentukan energi yang diperoleh oleh fluida kerja secara optimal pada kolektor surya tipe plat datar berdasarkan perubahan debit dan pemasangan batu-batu kerikil yang disusun secara teratur dan merata diatas permukaan plat absorber untuk memperluas permukaan dan meningkatkan temperatur dalam kolektor surya serta menentukan pengaruh penggunaan dua cermin datar terhadap energi berguna pada kolektor surya tipe plat datar secara eksperimen. Analisis termal ini dilakukan untuk memanfaatkan potensi radiasi matahari yang bisa mencapai 5,2 kWh/m2 sebagai media pemanas fluida kerja yaitu etanol 96% merupakan langkah awal penelitian. Kolektor surya tipe plat datar yang digunakan memiliki geometri panjang 1m, lebar 0,5 m, tinggi 0,18 m, kolektor surya dilapisi dua bahan yang berbeda yaitu polistirena foam dengan tebal 0,02 m dan armaflex dengan tebal 0,02 m. Pengambilan data dilakukan dengan sesuai variasi. Pengukuran besaran radiasi dan temperatur didalam box kolektor surya, temperatur pada satu kaca penutup, temperatur plat absorber, temperatur lingkungan, temperatur masuk etanol 96%, temperatur keluar etanol 96% dan kecepatan angin. Pengambilan radiasi matahari menggunakan kamera termal dan lux meter, temperatur menggunakan thermocouple tipe K, kecepatan angin menggunakan environment meter, dan debit menggunakan flow monitor. Hasil dari penelitian ini adalah temperatur capaian maksimum terjadi ketika debit maksimal 2.0 lpm, dengan batu kerikil pada plat absorber dan sudut reflektor 0⁰. Kata kunci: optimasi, analisis termal, kolektor surya Abstract

  10. Development of form stable Poly(methyl methacrylate) (PMMA) coated thermal phase change material for solar water heater applications

    Science.gov (United States)

    Munusamy, Y.; Shanmugam, S.; Shi-Ying, Kee

    2018-04-01

    Phase change material (PCM) is one of the most popular and widely used thermal energy storage material in solar water heater because it able to absorb and release a large amount of latent heat during a phase change process over a narrow temperature range. However the practical application of PCM is limited by two major issues; 1) leakage which leads to material loss and corrosion of tank and 2) large volume change during phase change process which cause pressure build up in the tank. In this work, form-stable PCM was prepared by coating myristic acid with Poly(methyl methacrylate) (PMMA) to prevent leakage of PCM. PMMA was mixed with different weight percentage (0.1, 0.2, 0.3, 0.4 and 0.5 wt%) of dicumyl peroxide (DCP). The purpose of adding DCP to PMMA is to crosslink the polymer and to increase the mechanical strength of PMMA to hold the myristic acid content inside the coating during the phase change process. Leakage test results showed that PMMA mixed with 0.1% DCP exhibit 0% leakage. This result is further supported by Field Emission Scanning Electron Microscopy (FESEM) images and Fourier transform infrared spectroscopy (FTIR) analysis results, where a compact and uniform coating without cracks were formed for PCM coated with PMMA with 0.1% DCP. Differential scanning calorimetry (DSC) results shows that the melting point of form-stable PCM is 55°C, freezing point is 50°C, the latent heat of melting and freezing is 67.59 J/g.

  11. The efficiency of the heat pump water heater, during DHW tapping cycle

    Science.gov (United States)

    Gużda, Arkadiusz; Szmolke, Norbert

    2017-10-01

    This paper discusses one of the most effective systems for domestic hot water (DHW) production based on air-source heat pump with an integrated tank. The operating principle of the heat pump is described in detail. Moreover, there is an account of experimental set-up and results of the measurements. In the experimental part, measurements were conducted with the aim of determining the energy parameters and measures of the economic efficiency related to the presented solution. The measurements that were conducted are based on the tapping cycle that is similar to the recommended one in EN-16147 standard. The efficiency of the air source heat pump during the duration of the experiment was 2.43. In the end of paper, authors conducted a simplified ecological analysis in order to determine the influence of operation of air-source heat pump with integrated tank on the environment. Moreover the compression with the different source of energy (gas boiler with closed combustion chamber and boiler fired by the coal) was conducted. The heat pump is the ecological friendly source of the energy.

  12. The efficiency of the heat pump water heater, during DHW tapping cycle

    Directory of Open Access Journals (Sweden)

    Gużda Arkadiusz

    2017-01-01

    Full Text Available This paper discusses one of the most effective systems for domestic hot water (DHW production based on air-source heat pump with an integrated tank. The operating principle of the heat pump is described in detail. Moreover, there is an account of experimental set-up and results of the measurements. In the experimental part, measurements were conducted with the aim of determining the energy parameters and measures of the economic efficiency related to the presented solution. The measurements that were conducted are based on the tapping cycle that is similar to the recommended one in EN-16147 standard. The efficiency of the air source heat pump during the duration of the experiment was 2.43. In the end of paper, authors conducted a simplified ecological analysis in order to determine the influence of operation of air-source heat pump with integrated tank on the environment. Moreover the compression with the different source of energy (gas boiler with closed combustion chamber and boiler fired by the coal was conducted. The heat pump is the ecological friendly source of the energy.

  13. Detailed Theoretical Characterization of a Transcritical CO2 Direct Expansion Ground Source Heat Pump Water Heater

    Directory of Open Access Journals (Sweden)

    Parham Eslami-Nejad

    2018-02-01

    Full Text Available A new avenue in modern heat pump technology is related to the use of natural refrigerants such as carbon dioxide (CO2. The use of CO2 in direct expansion ground source heat pumps (DX-GSHP has also gained significant interest as it offers opportunities for cost reduction of the ground loop, albeit some challenges remain in their development, design and use. To address these challenges and to characterize CO2-DX-GSHP performance for water heating applications, a detailed theoretical model and a fully-instrumented test apparatus was developed and built at CanmetENERGY Research Laboratory. The theoretical model was validated against a set of experimental results and adopted to investigate the performance of the system over a wide operating range. Validation results showed that the model predicts the experimental results within the measurement uncertainty. A detailed system performance analysis was also performed using the theoretical model to understand the system behavior and explore the actions required for performance improvement in future installations. The results of the analysis showed that improper design and control of some components, such as the gas cooler and ground heat exchanger can degrade the system performance by up to 25%, and the heat pump heating capacity by 7.5%.

  14. UPQC (Unified power Quality Conditioner)

    Indian Academy of Sciences (India)

    First page Back Continue Last page Graphics. UPQC (Unified power Quality Conditioner). Hybrid of Shunt and Series compensator. Compensate both Current Quality and Voltage Quality. Costlier Solution as it involves two set of Inverters.

  15. Experimental and numerical study of heat transfer phenomena, inside a flat-plate integrated collector storage solar water heater (ICSSWH), with indirect heat withdrawal

    International Nuclear Information System (INIS)

    Gertzos, K.P.; Pnevmatikakis, S.E.; Caouris, Y.G.

    2008-01-01

    The thermal behavior of a particular flat-plate integrated collector storage solar water heater (ICSSWH) is examined, experimentally and numerically. The particularity consists of the indirect heating of the service hot water, through a heat exchanger incorporated into front and back major surfaces of the ICSSWH. Natural and forced convection mechanisms are both examined. A prototype tank was fabricated and experimental data of temperature profiles are extracted, during various energy withdrawals. A 3D computational fluid dynamics (CFD) model was developed and validated against experimental results. Numerical predictions are found highly accurate, providing thus the use of the 3D CFD model for the optimization of this and similar devices

  16. Replacement of the level control of draining tanks MSRS and powered water heaters with the OVATION system in Asco NPP

    International Nuclear Information System (INIS)

    Serrano Jimenez, J.

    2012-01-01

    The current MSR drains and heaters tanks level control is local control individual, pneumatic and without action from Control room. The system has level switches for the generation of alarms, isolations and shots of bombs. Single control room operators have level alarms, final race of valves of control and indication of temperature and pressure of some tanks.

  17. 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.

  18. Design of a unit to produce hot distilled water for the same power consumption as a water heater

    Science.gov (United States)

    Bambenek, R. A.; Nuccio, P. P.

    1973-01-01

    Unit recovers 97% of water contained in pretreated waste water. Some factors are: cleansing agent prevents fouling of heat transfer surface by highly concentrated waste; absence of dynamic seals reduces required purge gas flow rate; and recycle loop maintains constant flushing process to carry cleansing agent across evaporation surface.

  19. Model based control and optimization of a feed-water heater train; Modellbaserad reglering och optimering av en foervaermarekedja

    Energy Technology Data Exchange (ETDEWEB)

    Velut, Stephane; Raaberg, Martin; Wendel, Hans (Grontmij AB (SE))

    2007-12-15

    Thermal power plants are complex processes in which many variables must be monitored and controlled in real-time for a safe and economic operation. The complex interactions between actuators and controlled variables as well as the load dependent dynamics make the design and tuning of all controllers a challenging task. A mathematical model of the process that describes critical characteristics such as dynamics, interactions, and nonlinearities might greatly facilitate the task of the control engineer. Such controllers can be designed in a rather systematic way to achieve good performance in terms of response time and robustness. This enables the operator to run the process closer to its limits while minimizing damage risks. The goal of the project was threefold. The first objective was to describe the available methods to compute process models directly from experimental data and illustrate how those models can be used for control design. The second objective was to apply some of the fore mentioned methods on a specific process, namely a feed water heater train to control the level in each preheater. The third objective was to analyze how the level in each preheater affects the thermal efficiency of the plant and derive adequate set-points for the model-based controllers. The project started at the end of the production season, which resulted in a tight schedule for the planning and the realization of experiments. Informative data could however be collected and models could be derived for some specific loads. Unfortunately the effect of the changes in the level set point could not be verified because of the limited length of the experiments. The project results can be summarized as follows: The way the condensate level should be chosen in every preheater has been formulated as a simple optimization problem that aims as maximizing the thermal efficiency of the plant. Even though the model used in the optimization was simple, the results were pretty intuitive. The

  20. Numerical investigation on effect of riser diameter and inclination on system parameters in a two-phase closed loop thermosyphon solar water heater

    International Nuclear Information System (INIS)

    Aung, Nay Zar; Li, Songjing

    2013-01-01

    Highlights: • Optimum inclination for maximum heat flux changes with latitude of location. • Optimum inclination for maximum heat flux also changes local solar time. • Maximum flow rate increases with increasing of riser tube size. • Maximum mass flow rate is obtained at different inclinations for different risers. • Length of two-phase region depends on inclination angles but not riser tube size. - Abstract: In this work, the effect of riser diameter and its inclination angle on system parameters in a two-phase closed loop thermosyphon solar water heater has been numerically investigated. Here, receivable heat flux by the collector, circulating mass flow rate, driving pressure, total pressure drop, heat transfer coefficient in risers and collector efficiency are defined as system parameters. For this aim, a model of two-phase thermosyphon solar water heater that is acceptable for various inclinations is presented and variations of riser diameter and inclination are considered. The riser tube size is varied from 1.25 cm to 2.5 cm with inclination range 2–75°. The system absolute pressure is set as 3567 Pa and water is chosen as working fluid. The results show that higher inclination angle is required for higher latitude location to obtain maximum solar heat flux. At local solar noon of 21.996 north latitude, the optimum inclination angle increases in the range of 24–44° with increasing of riser diameter giving maximum circulating mass flow rate from 0.02288 kg/s to 0.03876 kg/s. The longer two-phase heat transfer characteristics can be obtained at smaller inclination angles and mass flow rate for all riser tube sizes. Therefore, it is observed that the optimum inclination angles and diameters for solar heat flux, circulating mass flow rate and heat transfer coefficient in two-phase thermosyphon systemdo not coincide. From this work, better understanding and useful information are provided for constructing two-phase thermosyphon solar heaters

  1. Heater test in the Opalinus Clay of the Mont Terri URL. Gas release and water redistribution - Contribution to heater experiment (HE); Rock and bentonite thermo-hydro-mechanical (THM) processes in the nearfield

    International Nuclear Information System (INIS)

    Jockwer, N.; Wieczorek, K.

    2006-06-01

    Beside salt and granite, clay formations are investigated as potential host rocks for disposing radioactive waste. In Switzerland in the canton Jura close to the city of St. Ursanne, an underground laboratory was built in the vicinity of the reconnaissance gallery of a motorway tunnel. Since 1995, a consortium of 12 international organisations is running this laboratory for investigating the suitability of the Opalinus clay formation with regard to disposal of radioactive waste. In 1999, the Heater Experiment B (HE-B) was started for investigating the coupled thermo-hydro-mechanical (THM) processes of the Opalinus clay in interaction with the bentonite buffer. The principal contractors of this project were the Bundesanstalt fuer Geowissenschaften und Rohstoffe (BGR), the Empresa Nacional de Residuos Radiactivos S. A. (ENRESA), the Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, and the National Cooperative for the Disposal of Radioactive Waste (NAGRA). GRS participated in that experiment for determining the subjects of gas generation, gas release, water content, and water redistribution in the Opalinus clay during heating. This was achieved by analysing gas and water samples from the test field before, during, and after the heating period and by performing geoelectric tomography measurements in the heated region. The in-situ measurements were supported by an additional laboratory programme. This report deals with the work of GRS performed in this project during the years 1999 to 2005. All the results obtained in the frame of the project are presented. Additional laboratory measurements conducted by the Pore Water Laboratory at CIEMAT in Madrid are also presented. The participation of GRS was funded by German Ministry of Economics and Labour (BMWA) under the contract No. 02 E 9602 and by the Commission of the European Communities under the contract No. FIKW.CT-2001-00132. (orig.)

  2. Cost effectiveness analysis for the substitution of the electrical shower to gas water heaters; Estudo de viabilidade para substituicao do chuveiro eletrico por aquecedores a gas

    Energy Technology Data Exchange (ETDEWEB)

    Bermann, Celio [Sao Paulo Univ., SP (Brazil). Escola Politecnica. Inst. de Eletrotecnica e Energia]. E-mail: cbermann@iee.usp.br; Monteiro, Jorge Venancio de Freitas [Companhia de Gas de Sao Paulo (COMGAS), Sao Paulo, SP (Brazil)]. E-mail: venanciocomgas@uol.com.br

    2000-07-01

    The hydropower natural resources for generation of electrical energy at the south part of Brazil has been extinguished at the last years and as a consequence large investments should be made in order to attend the electrical energy demand at this part of country. These paper purposes a comparison between the use gas water heater and the traditional electrical shower largely applied at the Brazilian residences. It will be focused not only the consumer point of view but also the construction enterprise position as well as the advantages for the overall country due to this substitution. (author)

  3. Performance Study of a Cylindrical Parabolic Concentrating Solar Water Heater with Nail Type Twisted Tape Inserts in the Copper Absorber Tube

    Directory of Open Access Journals (Sweden)

    Amit K. Bhakta

    2018-01-01

    Full Text Available This paper reports the overall thermal performance of a cylindrical parabolic concentrating solar water heater (CPCSWH with inserting nail type twisted tape (NTT in the copper absorber tube for the nail twist pitch ratios, 4.787, 6.914 and 9.042, respectively. The experiments are conducted for a constant volumetric water flow rate and during the time period 9:00 a.m. to 15:00 p.m. The useful heat gain, hourly solar energy collected and hourly solar energy stored in this solar water heater were found to be higher for the nail twist pitch ratio 4.787. The above said parameters were found to be at a peak at noon and observed to follow the path of variation of solar intensity. At the start of the experiment, the value of charging efficiency was observed to be maximum, whereas the maximum values of instantaneous efficiency and overall thermal efficiency were observed at noon. The key finding is that the nail twist pitch ratio enhances the overall thermal performance of the CPCSWH.

  4. Air conditioner for radioactive material handling facility

    International Nuclear Information System (INIS)

    Tanaka, Takeaki.

    1991-01-01

    An air conditioner intakes open-air from an open-air intake port to remove sands and sea salt particles by air filters. Then, natural and artificial radioactive particles of less than 1 μm are removed by high performance particulate filters. After controlling the temperature by an air heater or an air cooler, air is sent to each of chambers in a facility under pressure elevation by a blower. In this case, glass fibers are used as the filter material for the high performance particulate filter, which has a performance of more than 99.97% for the particles of 0.3 μm grain size. Since this can sufficiently remove the natural radioactive materials intruded from the outside, a detection limit value in each of the chambers of the facility can be set 10 -13 to 10 -14 μci/cm 3 in respect of radiation control. Accordingly, radiation control can be conducted smoothly and appropriately. (I.N.)

  5. 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 2, Fluorescent lamp ballasts, television sets, room air conditioners, and kitchen ranges and ovens

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-01

    This document is divided into ``volumes`` B through E, dealing with individual classes of consumer products. Chapters in each present engineering analysis, base case forecasts, projected national impacts of standards, life-cycle costs and payback periods, impacts on manufacturers, impacts of standards on electric utilities, and environmental effects. Supporting appendices are included.

  6. Optimal design and placement of serpentine heat exchangers for indirect heat withdrawal, inside flat plate integrated collector storage solar water heaters (ICSSWH)

    Energy Technology Data Exchange (ETDEWEB)

    Gertzos, K.P.; Caouris, Y.G.; Panidis, T. [Dept. of Mechanical Engineering and Aeronautics, University of Patras, 265 00 Patras (Greece)

    2010-08-15

    Parameters that affect the temperature at which service hot water (SHW) is offered by an immersed tube heat exchanger (HX), inside a flat plate Integrated Collector Storage Solar Water Heater (ICSSWH), are examined numerically, by means of Computational Fluid Dynamics (CFD) analysis. The storage water is not refreshed and serves for heat accumulation. Service hot water is drawn off indirectly, through an immersed serpentine heat exchanger. For the intensification of the heat transfer process, the storage water is agitated by recirculation through a pump, which goes on only when service water flows inside the heat exchanger. Three main factors, which influence the performance, are optimized: The position of the HX relative to tank walls, the HX length and the tube diameter. All three factors are explored so that to maximize the service water outlet temperature. The settling time of the optimum configuration is also computed. Various 3-D CFD models were developed using the FLUENT package. The heat transfer rate between the two circuits of the optimum configuration is maintained at high levels, leading to service water outlet temperatures by 1-7 C lower than tank water temperatures, for the examined SHW flow rates. The settling time is retained at sufficient law values, such as 20 s. The optimal position was found to lay the HX in contact with the front and back walls of the tank, with an optimum inner tube diameter of 16 mm, while an acceptable HX length was found to be about 21.5 m. (author)

  7. Radioactivity leakage accidents in the feed water heater and the general drainage of the Tsuruga Nuclear Power Station of Japan Atomic Power Company

    International Nuclear Information System (INIS)

    1981-01-01

    In the Tsuruga Nuclear Power Station, JAPC on the shell on extracted-steam side in B system of No. 4 feed water heater, drain water leakage occurred twice in January, 1981. Then, 61 pCi/g cobalt-60 and 10 pCi/g manganese-54 were detected in soil at the outlet of general drainage on April 17, 1981. The cause was found to be the overflow of radioactive liquid waste in the filter sludge storage tank on March 8, the same year. On-the-spot inspection was subsequently made by the Agency of Natural Resources and Energy on both leakage accidents. The results of inspections are described as follows: the course of leakage accident, and also the measures taken to JAPC in connection with the two leakage accidents. (J.P.N.)

  8. China's transition to green energy systems: The economics of home solar water heaters and their popularization in Dezhou city

    Energy Technology Data Exchange (ETDEWEB)

    Li Wei, E-mail: weiweileede@gmail.com [Department of Economics, Macquarie University, Sydney, NSW 2109 (Australia); Song Guojun [Environmental Policy and Planning Institute (EPPI), Renmin University of China, Beijing (China); Beresford, Melanie [Department of Economics, Macquarie University, Sydney, NSW 2109 (Australia); Ma, Ben [Environmental Policy and Planning Institute (EPPI), Renmin University of China, Beijing (China)

    2011-10-15

    Studying the popularization of solar water heaters (SWHs) is significant for understanding China's transition to green energy systems. Using Dezhou as a case study, this paper presents new angles on analyzing SWH deployment in China by addressing both the economic potential and the institutional dimensions at the local level. Using estimates from the demand-side of hot water for a typical three-person household in Dezhou, the paper evaluates the economic potential of a SWH in saving electricity and reducing carbon dioxide emissions. Then, expanding the analysis beyond economics, we take an institutionalist approach to study the institutional factors that contribute to Dezhou's success in SWH adoptions. By examining the five main actors in Dezhou's energy regime, we find that Dezhou's SWH deployment is driven by an urge to develop businesses and the local economy, and its success results from at least five unique factors, including the development of SWH industrial clusters in Dezhou, big manufacturers' market leadership in SWH innovations, a tight private enterprise-local government relation, geographic location within the SWH industrial belt, and the adaptive attitude of Dezhou's households towards natural resource scarcity. - Highlights: > We study the popularization of solar water heaters in Dezhou, China. > We study the institutional factors that contribute to Dezhou's success. > Five main actors in Dezhou's energy regime are examined. > Dezhou's success results from at least five unique factors. > This leads to important directions for improving China'ss green innovation adoption.

  9. Assessment of radioisotope heaters for remote terrestrial applications

    International Nuclear Information System (INIS)

    Uherka, K.L.

    1987-05-01

    This paper examines the feasibility of using radioisotope byproducts for special heating applications at remote sites in Alaska and other cold regions. The investigation included assessment of candidate radioisotope materials for heater applications, identification of the most promising cold region applications, evaluation of key technical issues and implementation constraints, and development of conceptual heater designs for candidate applications. Strontium-90 (Sr-90) was selected as the most viable fuel for radioisotopic heaters used in terrestrial applications. Opportunities for the application of radioisotopic heaters were determined through site visits to representative Alaska installations. Candidate heater applications included water storage tanks, sludge digesters, sewage lagoons, water piping systems, well-head pumping stations, emergency shelters, and fuel storage tank deicers. Radioisotopic heaters for water storage tank freeze-up protection and for enhancement of biological waste treatment processes at remote sites were selected as the most promising applications

  10. Experimental investigation of heat transfer and friction factor characteristics of thermosyphon solar water heater system fitted with spacer at the trailing edge of Left-Right twisted tapes

    International Nuclear Information System (INIS)

    Jaisankar, S.; Radhakrishnan, T.K.; Sheeba, K.N.; Suresh, S.

    2009-01-01

    Experimental investigation of heat transfer and friction factor characteristics of thermosyphon solar water heater with full length Left-Right twist, twist fitted with rod and spacer at the trailing edge for lengths of 100, 200 and 300 mm for twist ratio 3 and 5 has been studied. The experimental data for plain tube collector has been compared with fundamental equation within a discrepancy of ±7.41% and ±14.97% for Nusselt number and friction factor, respectively. Result shows that the Nusselt number decreases by 11% and 19% for twist fitted with rod and twist with spacer, respectively, when compared with full length twist. Friction factor also decreases by 18% and 29% for twist fitted with rod and spacer, respectively, as compared with full length twist. The heat enhancement in twist fitted with rod at the trailing edge is maximum when compared with twist fitted with spacer because the swirl flow is maintained throughout the length of rod.

  11. Shuttle APS propellant thermal conditioner study

    Science.gov (United States)

    Pearson, W. E.

    1971-01-01

    A study program was performed to allow selection of thermal conditioner assemblies for superheating O2 and H2 at supercritical pressures. The application was the auxiliary propulsion system (APS) for the space shuttle vehicle. The O2/H2 APS propellant feed system included propellant conditioners, of which the thermal conditioner assemblies were a part. Cryogens, pumped to pressures above critical, were directed to the thermal conditioner assembly included: (1) a gas generator assembly with ignition system and bipropellant valves, which burned superheated O2 and H2 at rich conditions; (2) a heat exchanger assembly for thermal conditioning of the cryogenic propellant; and (3) a dump nozzle for heat exchanger exhaust.

  12. A thermodynamic analysis of a transcritical cycle with refrigerant mixture R32/R290 for a small heat pump water heater

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Jianlin; Xu, Zong; Tian, Gaolei [Department of Refrigeration and Cryogenic Engineering, School of Energy and Power Engineering, Xi' an Jiaotong University, West Xianning Road, No. 28, Xianning West Road, Xi' an Shaanxi 710049 (China)

    2010-12-15

    In this study, a thermodynamic analysis on the performance of a transcritical cycle using azeotropic refrigerant mixtures of R32/R290 with mass fraction of 70/30 has been performed. The main purpose of this study is to theoretically verify the possibility of applying the chosen refrigerant mixture in small heat pumps for high temperature water heating applications. Performance evaluation has been carried out for a simple azeotropic mixture R32/R290 transcritical cycle by varying evaporator temperature, outlet temperature of gas cooler and compressor discharge pressure. Furthermore, the effects of an internal heat exchanger on the transcritical R32/R290 cycle have been presented at different operating conditions. The results show that high heating coefficient of performance (COP{sub h}) and volumetric heating capacity can be achieved by using this transcritical cycle. It is desirable to apply the chosen refrigerant mixture R32/R290 in small heat pump water heater for high temperature water heating applications, which may produce hot water with temperature up to 90 C. (author)

  13. Novel Method for Measuring the Heat Collection Rate and Heat Loss Coefficient of Water-in-Glass Evacuated Tube Solar Water Heaters Based on Artificial Neural Networks and Support Vector Machine

    Directory of Open Access Journals (Sweden)

    Zhijian Liu

    2015-08-01

    Full Text Available The determinations of heat collection rate and heat loss coefficient are crucial for the evaluation of in service water-in-glass evacuated tube solar water heaters. However, the direct determination requires complex detection devices and a series of standard experiments, which also wastes too much time and manpower. To address this problem, we propose machine learning models including artificial neural networks (ANNs and support vector machines (SVM to predict the heat collection rate and heat loss coefficient without a direct determination. Parameters that can be easily obtained by “portable test instruments” were set as independent variables, including tube length, number of tubes, tube center distance, heat water mass in tank, collector area, final temperature and angle between tubes and ground, while the heat collection rate and heat loss coefficient determined by the detection device were set as dependent variables respectively. Nine hundred fifteen samples from in-service water-in-glass evacuated tube solar water heaters were used for training and testing the models. Results show that the multilayer feed-forward neural network (MLFN with 3 nodes is the best model for the prediction of heat collection rate and the general regression neural network (GRNN is the best model for the prediction of heat loss coefficient due to their low root mean square (RMS errors, short training times, and high prediction accuracies (under the tolerances of 30%, 20%, and 10%, respectively.

  14. Portable Body Temperature Conditioner

    Science.gov (United States)

    2014-12-01

    temperature is 36.0o C. The patient complains of severe abdominal pain and intra- abdominal injury is suspected. In this scenario the patient is...hypothermia will shiver, experience pain , and on a whole be really uncomfortable. If they are sufficiently obtunded to require this therapy then they...Convective hyper- hypothermia water blankets/wraps Single-Use Blanket Maxi-Therm Adult Box 5 $127.00 Pediatric Box 5 $90.00 Infant Box 5 $72.00

  15. Development of a solar-powered residential air conditioner: System optimization preliminary specification

    Science.gov (United States)

    Rousseau, J.; Hwang, K. C.

    1975-01-01

    Investigations aimed at the optimization of a baseline Rankine cycle solar powered air conditioner and the development of a preliminary system specification were conducted. Efforts encompassed the following: (1) investigations of the use of recuperators/regenerators to enhance the performance of the baseline system, (2) development of an off-design computer program for system performance prediction, (3) optimization of the turbocompressor design to cover a broad range of conditions and permit operation at low heat source water temperatures, (4) generation of parametric data describing system performance (COP and capacity), (5) development and evaluation of candidate system augmentation concepts and selection of the optimum approach, (6) generation of auxiliary power requirement data, (7) development of a complete solar collector-thermal storage-air conditioner computer program, (8) evaluation of the baseline Rankine air conditioner over a five day period simulating the NASA solar house operation, and (9) evaluation of the air conditioner as a heat pump.

  16. Thermal performance analysis of a flat heat pipe working with carbon nanotube-water nanofluid for cooling of a high heat flux heater

    Science.gov (United States)

    Arya, A.; Sarafraz, M. M.; Shahmiri, S.; Madani, S. A. H.; Nikkhah, V.; Nakhjavani, S. M.

    2018-04-01

    Experimental investigation on the thermal performance of a flat heat pipe working with carbon nanotube nanofluid is conducted. It is used for cooling a heater working at high heat flux conditions up to 190 kW/m2. The heat pipe is fabricated from aluminium and is equipped with rectangular fin for efficient cooling of condenser section. Inside the heat pipe, a screen mesh was inserted as a wick structure to facilitate the capillary action of working fluid. Influence of different operating parameters such as heat flux, mass concentration of carbon nanotubes and filling ratio of working fluid on thermal performance of heat pipe and its thermal resistance are investigated. Results showed that with an increase in heat flux, the heat transfer coefficient in evaporator section of the heat pipe increases. For filling ratio, however, there is an optimum value, which was 0.8 for the test heat pipe. In addition, CNT/water enhanced the heat transfer coefficient up to 40% over the deionized water. Carbon nanotubes intensified the thermal performance of wick structure by creating a fouling layer on screen mesh structure, which changes the contact angle of liquid with the surface, intensifying the capillary forces.

  17. Conditioner for a helically transported electron beam

    International Nuclear Information System (INIS)

    Wang, Changbiao.

    1992-05-01

    The kinetic theory is developed to investigate a conditioner for a helically transported electron beam. Linear expressions for axial velocity spread are derived. Numerical simulation is used to check the theoretical results and examine nonlinear aspects of the conditioning process. The results show that in the linear regime the action of the beam conditioner on a pulsed beam mainly depends on the phase at which the beam enters the conditioner and depends only slightly on the operating wavelength. In the nonlinear regime, however, the action of the conditioner strongly depends on the operating wavelength and only slightly upon the entrance phase. For a properly chosen operating wavelength, a little less than the electron's relativistic cyclotron wavelength, the conditioner can decrease the axial velocity spread of a pulsed beam down to less than one-third of its initial value

  18. Conditioner for a helically transported electron beam

    International Nuclear Information System (INIS)

    Wang, C.

    1992-05-01

    The kinetic theory is developed to investigate a conditioner for a helically imported electron beam. Linear expressions for axial velocity spread are derived. Numerical simulation is used to check the theoretical results and examine nonlinear aspects of the conditioning process. The results show that in the linear regime the action of the beam conditioner on a pulsed beam mainly depends on the phase at which the beam enters the conditioner and depends only slightly on the operating wavelength. In the nonlinear regime, however, the action of the conditioner strongly depends on the operating wavelength and only slightly upon the entrance phase. For a properly chosen operating wavelength, a little less than the electron's relativistic cyclotron wavelength, the conditioner can decrease the axial velocity spread of a pulsed beam down to less than one-third of its initial value

  19. Space shuttle aps propellant thermal conditioner study

    Science.gov (United States)

    Fulton, D. L.

    1973-01-01

    An analytical and experimental effort was completed to evaluate a baffle type thermal conditioner for superheating O2 and H2 at supercritical pressures. The thermal conditioner consisted of a heat exchanger and an integral reactor (gas generator) operating on O2/H2 propellants. Primary emphasis was placed on the hydrogen conditioner with some effort on the oxygen conditioner and a study completed of alternate concepts for use in conditioning oxygen. A hydrogen conditioner was hot fire tested under a range of conditions to establish ignition, heat exchange and response parameters. A parallel technology task was completed to further evaluate the integral reactor and heat exchanger with the side mounted electrical spark igniter.

  20. Formulation of humic-based soil conditioners

    Science.gov (United States)

    Amanova, M. A.; Mamytova, G. A.; Mamytova, B. A.; Kydralieva, K. A.; Jorobekova, Sh. J.

    2009-04-01

    The goal of the study is to prepare soil conditioners (SC) able to carry out the following functions: (i) the chemical conditioning of soil mainly comprising the adjustment of pH, (ii) the balancing of inorganic nutrients, (iii) the physical conditioning of soil mainly comprising the improvement of water permeability, air permeability and water retention properties, and (iv) improvement of the ecological system concerning of useful microorganisms activity in the soil. The SC was made of a mixture of inorganic ingredients, a chemical composition and physical and chemical properties of which promoted improvement of physical characteristic of soil and enrichment by its mineral nutritious elements. In addition to aforesaid ingredients, this soil conditioner contains agronomical-valued groups of microorganisms having the function promoting the growth of the crop. As organic component of SC humic acids (HA) was used. HA serve many major functions that result in better soil and plant health. In soil, HA can increase microbial and mycorrhizal activity while enhancing nutrient uptake by plant roots. HA work as a catalyst by stimulating root and plant growth, it may enhance enzymatic activity that in turn accelerates cell division which can lead to increased yields. HA can help to increase crop yields, seed germination, and much more. In short, humic acids helps keep healthy plants health. The first stage goal was to evaluate mineral and organic ingredients for formulation of SC. Soil conditioners assessed included ash and slag. The use of slags has been largelly used in agriculture as a source of lime and phosphoric acid. The silicic acid of slags reduces Al-acitivity thus, promoting a better assimilation of P-fertilizer by plants. Additionally, silicic acid is also known to improve soil moisture capacity, thus enhancing soil water availability to plants. Physico-chemical characteristics of ash and slag were determined, as a total - about 20 samples. Results include

  1. Test of the heatpump system Fre-Heater model D, made by Mueller Europa BV. Installation for the cooling of milk and the heating of water on farms. Beproeving van een warmtepompsysteem, type Fre-Heater model D, fabrikaat Mueller. Installatie voor het koelen van melk en het verwarmen van water op de boerderij

    Energy Technology Data Exchange (ETDEWEB)

    Verheij, C P; de Vries, J; van Haren, J J

    1982-01-01

    At the request of Mueller Europa BV (the Netherlands) the Fre-Heater D heat-pump system was tested for its suitability for the simultaneous cooling of milk and the heating of water on farms. The main purpose of the test was to provide information about the technical properties of the system and about the possibilities it offers for the saving of energy. The test was carried out according to the directives laid down in the 'Beproevingsmethode voor warmtepompsystemen ten behoeve van het verwarmen van water op de boerderij' (Test method for heat-pump systems for the heating of water on farms), issued by the Netherlands Institute for Dairy Research, 1980. The results obtained in the tests were used for the calculation of the savings of energy. The system was compared with a conventional air-cooled refrigerated farm milk tank with a COPR (coefficient of performance of refrigeration) of 2.5. The Fre-Heater D was found to have a COPR of 2.40. The net savings of energy that could be achieved varied from 20.9 to 13.8 kWh per m3 cooled 'milk' at farm sizes from 40 to 78 cows. Based on a price of electrical energy of Dfl 0.20 per kWh, this installation was found to be economically justified at a farm with 40 cows and more (milk production 5.5 m3 per cow per year). For a farm with 40 cows the pay-back period was found to be 4.1 years, and for a farm with 78 cows this period was 3.2 years.

  2. Load Frequency Control by use of a Number of Both Heat Pump Water Heaters and Electric Vehicles in Power System with a Large Integration of Renewable Energy Sources

    Science.gov (United States)

    Masuta, Taisuke; Shimizu, Koichiro; Yokoyama, Akihiko

    In Japan, from the viewpoints of global warming countermeasures and energy security, it is expected to establish a smart grid as a power system into which a large amount of generation from renewable energy sources such as wind power generation and photovoltaic generation can be installed. Measures for the power system stability and reliability are necessary because a large integration of these renewable energy sources causes some problems in power systems, e.g. frequency fluctuation and distribution voltage rise, and Battery Energy Storage System (BESS) is one of effective solutions to these problems. Due to a high cost of the BESS, our research group has studied an application of controllable loads such as Heat Pump Water Heater (HPWH) and Electric Vehicle (EV) to the power system control for reduction of the required capacity of BESS. This paper proposes a new coordinated Load Frequency Control (LFC) method for the conventional power plants, the BESS, the HPWHs, and the EVs. The performance of the proposed LFC method is evaluated by the numerical simulations conducted on a power system model with a large integration of wind power generation and photovoltaic generation.

  3. Coupled solar still, solar heater

    Energy Technology Data Exchange (ETDEWEB)

    Davison, R R; Harris, W B; Moor, D H; Delyannis, A; Delyannis, E [eds.

    1976-01-01

    Computer simulation of combinations of solar stills and solar heaters indicates the probable economic advantage of such an arrangement in many locations if the size of the heater is optimized relative to that of the still. Experience with various low cost solar heaters is discussed.

  4. Application of evaporative cooling on the condenser of window-air-conditioner

    International Nuclear Information System (INIS)

    Hajidavalloo, Ebrahim

    2007-01-01

    Reduction of energy consumption is a major concern in the vapor compression refrigeration cycle especially in the area with very hot weather conditions (about 50 deg. C), where window-air-conditioners are usually used to cool homes. In this weather condition performance of air condenser window-air-conditioners decrease sharply and electrical power consumption increase considerably. These problems have activated the research programs in order to improve the performance of window-air-conditioners by enhancing heat transfer rate in the condenser. In this article, a new design with high commercialization potential for incorporating of evaporative cooling in the condenser of window-air-conditioner is introduced and experimentally investigated. A real air conditioner is used to test the innovation by putting two cooling pads in both sides of the air conditioner and injecting water on them in order to cool down the air before it passing over the condenser. The experimental results show that thermodynamic characteristics of new system are considerably improved and power consumption decreases by about 16% and the coefficient of performance increases by about 55%

  5. Application of evaporative cooling on the condenser of window-air-conditioner

    Energy Technology Data Exchange (ETDEWEB)

    Hajidavalloo, Ebrahim [Shahid Chamran University, Department of Mechanical Engineering, Golestan St., Ahwaz, Khoozestan 61355 (Iran, Islamic Republic of)]. E-mail: hajidae_1999@yahoo.com

    2007-08-15

    Reduction of energy consumption is a major concern in the vapor compression refrigeration cycle especially in the area with very hot weather conditions (about 50 deg. C), where window-air-conditioners are usually used to cool homes. In this weather condition performance of air condenser window-air-conditioners decrease sharply and electrical power consumption increase considerably. These problems have activated the research programs in order to improve the performance of window-air-conditioners by enhancing heat transfer rate in the condenser. In this article, a new design with high commercialization potential for incorporating of evaporative cooling in the condenser of window-air-conditioner is introduced and experimentally investigated. A real air conditioner is used to test the innovation by putting two cooling pads in both sides of the air conditioner and injecting water on them in order to cool down the air before it passing over the condenser. The experimental results show that thermodynamic characteristics of new system are considerably improved and power consumption decreases by about 16% and the coefficient of performance increases by about 55%.

  6. Immersible solar heater for fluids

    Science.gov (United States)

    Kronberg, James W.

    1995-01-01

    An immersible solar heater comprising a light-absorbing panel attached to a frame for absorbing heat energy from the light and transferring the absorbed heat energy directly to the fluid in which the heater is immersed. The heater can be used to heat a swimming pool, for example, and is held in position and at a preselected angle by a system of floats, weights and tethers so that the panel can operate efficiently. A skid can be used in one embodiment to prevent lateral movement of the heater along the bottom of the pool. Alternative embodiments include different arrangements of the weights, floats and tethers and methods for making the heater.

  7. Research on a Household Dual Heat Source Heat Pump Water Heater with Preheater Based on ASPEN PLUS

    Directory of Open Access Journals (Sweden)

    Xiang Gou

    2016-12-01

    Full Text Available This article proposes a dual heat source heat pump bathroom unit with preheater which is feasible for a single family. The system effectively integrates the air source heat pump (ASHP and wastewater source heat pump (WSHP technologies, and incorporates a preheater to recover shower wastewater heat and thus improve the total coefficient of performance (COP of the system, and it has no electric auxiliary heating device, which is favorable to improve the security of the system operation. The process simulation software ASPEN PLUS, widely used in the design and optimization of thermodynamic systems, was used to simulate various cases of system use and to analyze the impact of the preheater on the system. The average COP value of a system with preheater is 6.588 and without preheater it is 4.677. Based on the optimization and analysis, under the standard conditions of air at 25 °C, relative humidity of 70%, wastewater at 35 °C, wastewater flow rate of 0.07 kg/s, tap water at 15 °C, and condenser outlet water temperature at 50 °C, the theoretical COP of the system can reach 9.784 at an evaporating temperature of 14.96 °C, condensing temperature of 48.74 °C, and preheated water temperature of 27.19 °C.

  8. Thermal analysis and performance optimization of a solar water heater flat plate collector: Application to Tetouan (Morocco)

    International Nuclear Information System (INIS)

    Dagdougui, Hanane; Ouammi, Ahmed; Robba, Michela; Sacile, Roberto

    2011-01-01

    The development of sustainable energy services like the supply of heating water may face a trade-off with a comfortable quality of life, especially in the winter season where suitable strategies to deliver an effective service are required. This paper investigates the heat transfer process as well as the thermal behavior of a flat plate collector evaluating different cover configurations. This investigation is performed according to a two-folded approach. Firstly, a complete model is formulated and implemented taking into account various modes of heat transfer in the collector. The goal is to investigate the impact of the number and types of covers on the top heat loss and the related thermal performance in order to support decision makers about the most cost-effective design. The proposed model can also be used to investigate the effect of the different parameters which may affect the performance of the collector. Secondly, a two objective constrained optimization model has been formulated and implemented to evaluate the optimality of different design approaches. The goal is to support decision makers in the definition of the optimal water flow and of the optimal collector flat area in order to give a good compromise between the collector efficiency and the output water temperature. The overall methodology has been tested on environmental data (temperature and irradiation) which are characteristic of Tetouan (Morocco). (author)

  9. ENERGY STAR Certified Room Air Conditioners

    Data.gov (United States)

    U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 4.0 ENERGY STAR Program Requirements for Room Air Conditioners that are effective as of...

  10. Ventilation-air conditioner system in nuclear power plant

    International Nuclear Information System (INIS)

    Kubota, Ryuji; Sugisaki, Toshihiko.

    1989-01-01

    This invention concerns a ventilation-air conditioner system which enables, upon occurrence of accidents in a nuclear power plant, continuous operation for other adjacent nuclear power plants with no effect of accidents. Air supply system and exhaust system are operated during usual operaiton. If loss of coolants accidents should occur in an adjacent nuclear power plants, operation is switched from ventilation operaiton to the operation of re-cycling system based on an AND logic of three signals, that is, a pressure HIGH signal for the reactor container, a water level LOW signal for the reactor and a radioactivity signal of the ventilation-air conditioner sytem on the side of air supply in the nuclear power plant. Thus, nuclear reactor buildings of the nuclear power plant are from the external atmosphere. Therefore, the radioactivity HIGH signal for switching to the emergency air conditioner system of the nuclear power plant is not actuated due to the loss of coolant accidents in the adjacent nuclear power plant. In addition, since the atmospheric temperature in the nuclear reactor building can be maintained by a cooling device disposed to the recycling system, reactor shutdown can be prevented. (I.S.)

  11. What makes renewable energy successful in China? The case of the Shandong province solar water heater innovation system

    International Nuclear Information System (INIS)

    Goess, Simon; Jong, Martin de; Ravesteijn, Wim

    2015-01-01

    The Chinese province of Shandong, and more particularly its cities Dezhou, Jinan and Rizhao, have established an international reputation of being hotbeds for solar water heating (SWH) technology development and dissemination. The article aims to unveil the evolution of this innovative environment by applying the Functions of Innovation Systems (FIS) approach to the Chinese province of Shandong. It examines the actors, institutions and policy instruments that shape Shandong's innovation system for SWH, the dominant drivers and barriers during the evolution of the TIS and also assesses the applicability of the IS approach to China. It appears that the presence of influential interest organizations and proactive support from local governments have acted as strong drivers for the emergence of Shandong's innovation system for SWHs. On the other hand, the lack of adequate personnel and an overreliance on government policies act as main barriers. With regard to the Chinese specificities potentially detracting from the relevance of applying IS theory to China, we did not find that the central government acted as an initiator of innovation nor that state-owned enterprises had dominant positions in the market. In this innovative industry the impetus for development came from the bottom up and from private corporations. - Highlights: • Application of the functions of innovation systems framework to Chinese province. • Analysis of the evolution of Shandong's solar water heating industry and market. • Local governments and interest organizations make innovation environment successful. • Bottom-up development and dissemination of renewable energy in China.

  12. Solar Ray Tracing Analysis to Determine Energy Availability in a CPC Designed for Use as a Residential Water Heater

    Directory of Open Access Journals (Sweden)

    Miguel Terrón-Hernández

    2018-01-01

    Full Text Available Compound parabolic concentrators are relevant systems used in solar thermal technology. With adequate tailoring, they can be used as an efficient and low-cost alternative in residential water heating applications. This work presents a simulation study using a ray tracing analysis. With this technique, we simulate the interaction between solar rays and solar concentrator to quantify the amount of energy that impinges on the receiver at a particular time. Energy availability is evaluated in a comparison of two configurations throughout the year: static setup at 21° and multi-position setup; tilted with respect to the horizontal, depending on three seasonal positions: 0° for summer, 16° for spring/autumn, and 32° for winter, with the aim to evaluate the amount of available energy in each season. The fact that a tracking system can be dispensed with also represents an economical option for the proposed application. The results showed that at 21°, the proposed solar Compound Parabolic Concentrator (CPC works satisfactorily; however, by carrying out the selected angular adjustments, the overall energy availability increased by 22%, resulting in a more efficient option. The most effective design was also built and analyzed outdoors. The obtained thermal efficiency was of ~43%. The optical design and its evaluation developed herein proved to be a valuable tool for prototype design and performance evaluation.

  13. Life cycle environmental impacts of domestic solar water heaters in Turkey: The effect of different climatic regions.

    Science.gov (United States)

    Uctug, Fehmi Gorkem; Azapagic, Adisa

    2018-05-01

    Solar water heating (SWH) systems could help reduce environmental impacts from energy use but their performance and impacts depend on the climate. This paper considers how these vary for residential SWH across four different climatic regions in Turkey, ranging from hot to cold climates. Life cycle assessment was used for these purposes. The results suggest that in the hotter regions, the impacts of SWH are 1.5-2 times lower than those of natural gas boilers. A similar trend was observed in the two colder regions except for acidification, which was four times higher than that of the boiler. The raw materials and electricity required for the manufacturing of the systems were found to be the most important contributors to the impacts. Recycling the major components instead of landfilling reduced human toxicity potential by 50% but had only a small effect (5%) on the other impacts. The impacts were highly sensitive to the type of material used for the construction of the hot storage tank, but were not affected by transport and end-of life recycling. The only exception to the latter is human toxicity potential which decreased significantly with greater recycling. Extrapolating the results at the national level showed that SWH systems could reduce the annual greenhouse gas emissions in Turkey by 790kt CO 2 -eq. and would save the economy $162.5millionperyear through the avoided imports of natural gas. All other impacts would also be reduced significantly (3-32 times), except for acidification which would double. Therefore, SWH systems should be deployed more extensively in Turkey but government incentives may be needed to stimulate the uptake. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. 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.

  15. 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.

  16. Experimental and theoretical investigation of Stirling engine heater: Parametrical optimization

    International Nuclear Information System (INIS)

    Gheith, R.; Hachem, H.; Aloui, F.; Ben Nasrallah, S.

    2015-01-01

    Highlights: • A Stirling engine was investigated to optimize its operation and its performance. • The porous medium present the highest amount of heat exchanged in a Stirling engine. • The heater characteristics are determinant points to enhance the thermal exchange in Stirling engine. • All operation parameters influence the heater performances. • Thermal and exergy heater efficiencies are sensible to temperature and pressure. - Abstract: The aim of this work is to optimize γ Stirling engine performances with a special care given to the heater. This latter consists of 20 tubes in order to increase the exchange area between the working gas and the hot source. Different parameters were chosen to evaluate numerically and experimentally the heater. The selected four independent parameters are: heating temperature (300–500 °C), initial filling pressure (3–8 bar), cooling water flow rate (0.2–3 l/min) and frequency (2–7 Hz). The amount of energy exchanged in the heater is significantly influenced by the frequency and heating temperature but it is slightly enhanced with the increase in the cooling water flow rate. The thermal and the exergy efficiencies of the heater are very sensible to the temperature and pressure variations.

  17. Performance investigation of a novel frost-free air-source heat pump water heater combined with energy storage and dehumidification

    International Nuclear Information System (INIS)

    Wang, Fenghao; Wang, Zhihua; Zheng, Yuxin; Lin, Zhang; Hao, Pengfei; Huan, Chao; Wang, Tian

    2015-01-01

    Highlights: • Experiments are carried out to investigate a novel frost-free ASHPWH system. • Dynamic characteristics of the system are studied at different ambient conditions. • Test results confirm the expected potential to control the frost-free process. • The COP increased 17.9% and 3.4% respectively in comparison with RCD at −3 °C and 3 °C. - Abstract: Air-source heat pump (ASHP) often operates with substantial frost formation on the outdoor heat exchanger at low ambient temperature in winter, it insulates the finned surface and also reduces heat transfer rate, leading to performance degradation or even shutdown of ASHP systems. Although several defrosting methods have been reported, the frosting and defrosting processes reduced energy efficiency and resulted in, in some cases, heat pump breakdown. To solve this problem, a novel frost-free air-source heat pump water heater (ASHPWH) system has been developed, which coupled with an extra heat exchanger coated by a solid desiccant (EHECSD) with an energy storage device (ESD). Based on the previous studies, a further analysis and comprehensive research on the novel frost-free ASHPWH system is presented in this paper. The dynamic characteristics of the novel system are investigated experimentally in different ambient conditions. An experimental setup and experimental procedures are described in detail. Thereafter, the dehumidification efficiency and regeneration efficiency of EHECSD, suction and discharge pressures of the compressor, the temperature of PCM are evaluated during the heating and regeneration modes respectively. Results indicate that the system can keep the evaporator frost-free for 32, 34, 36 min during heating mode at the ambient temperatures of −3 °C, 0 °C and 3 °C and 85% RH. Compared with the reverse-cycle defrosting (RCD), COP of the frost-free ASHPWH are 17.9% and 3.4% higher at the ambient temperature of −3 °C and 3 °C respectively. With this innovative technology, it has

  18. High Efficiency Room Air Conditioner

    Energy Technology Data Exchange (ETDEWEB)

    Bansal, Pradeep [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-01-01

    This project was undertaken as a CRADA project between UT-Battelle and Geberal Electric Company and was funded by Department of Energy to design and develop of a high efficiency room air conditioner. A number of novel elements were investigated to improve the energy efficiency of a state-of-the-art WAC with base capacity of 10,000 BTU/h. One of the major modifications was made by downgrading its capacity from 10,000 BTU/hr to 8,000 BTU/hr by replacing the original compressor with a lower capacity (8,000 BTU/hr) but high efficiency compressor having an EER of 9.7 as compared with 9.3 of the original compressor. However, all heat exchangers from the original unit were retained to provide higher EER. The other subsequent major modifications included- (i) the AC fan motor was replaced by a brushless high efficiency ECM motor along with its fan housing, (ii) the capillary tube was replaced with a needle valve to better control the refrigerant flow and refrigerant set points, and (iii) the unit was tested with a drop-in environmentally friendly binary mixture of R32 (90% molar concentration)/R125 (10% molar concentration). The WAC was tested in the environmental chambers at ORNL as per the design rating conditions of AHAM/ASHRAE (Outdoor- 95F and 40%RH, Indoor- 80F, 51.5%RH). All these modifications resulted in enhancing the EER of the WAC by up to 25%.

  19. 热泵与家用太阳热水器联合供热性能试验%Performance jointly test of heat pump water heater with household solar heating

    Institute of Scientific and Technical Information of China (English)

    谌学先; 高文峰; 兰青; 唐润生; 夏朝凤

    2011-01-01

    为解决家用太阳能热水器供热的间歇性和不稳定性,应用热泵辅助可达到全天候供热,该文通过对这种联合供热系统的供热性能和运行性能进行了测试,并对热水器的升温、保温和热泵的加热进行了试验和分析,结果表明:空气源热泵辅助型真空管家用太阳热水系统仅在累积太阳辐照量小于14 MJ/m2时,需要空气源热泵辅助加热,总制热性能系数可达6.18.%To solve the problems of heating intermittent and instability for household solar water heater, application of heat pump for evacuated tube solar water heater system can achieved auxiliary heat supply round-the-clock. Heating performance test and operation of the system were conducted and the temperature rise performance, heat preservation of the solar water heater system and the heating performance of heat pump were tested and analyzed in this paper. The result showed that when the solar radiation was less than 14 MJ/m2 , the system needed heating by air source heat pump,on this occasion, the system total coefficient of performance could reach 6.18.

  20. Photovoltaic array: Power conditioner interface characteristics

    Science.gov (United States)

    Gonzalez, C. C.; Hill, G. M.; Ross, R. G., Jr.

    1982-01-01

    The electrical output (power, current, and voltage) of flat plate solar arrays changes constantly, due primarily to changes in cell temperature and irradiance level. As a result, array loads such as dc-to-ac power conditioners must be capable of accommodating widely varying input levels while maintaining operation at or near the maximum power point of the array. The array operating characteristics and extreme output limits necessary for the systematic design of array load interfaces under a wide variety of climatic conditions are studied. A number of interface parameters are examined, including optimum operating voltage, voltage energy, maximum power and current limits, and maximum open circuit voltage. The effect of array degradation and I-V curve fill factor or the array power conditioner interface is also discussed. Results are presented as normalized ratios of power conditioner parameters to array parameters, making the results universally applicable to a wide variety of system sizes, sites, and operating modes.

  1. Low cost solar air heater

    International Nuclear Information System (INIS)

    Gill, R.S.; Singh, Sukhmeet; Singh, Parm Pal

    2012-01-01

    Highlights: ► Single glazed low cost solar air heater is more efficient during summer while double glazed is better in winter. ► For the same initial investment, low cost solar air heaters collect more energy than packed bed solar air heater. ► During off season low cost solar air heater can be stored inside as it is light in weight. - Abstract: Two low cost solar air heaters viz. single glazed and double glazed were designed, fabricated and tested. Thermocole, ultraviolet stabilised plastic sheet, etc. were used for fabrication to reduce the fabrication cost. These were tested simultaneously at no load and with load both in summer and winter seasons along with packed bed solar air heater using iron chips for absorption of radiation. The initial costs of single glazed and double glazed are 22.8% and 26.8% of the initial cost of packed bed solar air heater of the same aperture area. It was found that on a given day at no load, the maximum stagnation temperatures of single glazed and double glazed solar air heater were 43.5 °C and 62.5 °C respectively. The efficiencies of single glazed, double glazed and packed bed solar air heaters corresponding to flow rate of 0.02 m 3 /s-m 2 were 30.29%, 45.05% and 71.68% respectively in winter season. The collector efficiency factor, heat removal factor based on air outlet temperature and air inlet temperature for three solar air heaters were also determined.

  2. Mold contamination of automobile air conditioner systems.

    Science.gov (United States)

    Kumar, P; Lopez, M; Fan, W; Cambre, K; Elston, R C

    1990-02-01

    Eight cars belonging to patients who were found to have exacerbation of allergic rhinitis and bronchial asthma after turning on the air conditioner in their cars were examined. Mold concentrations inside the passenger compartment with the a/c turned off and at different climate control settings were lower than concentrations in the outside air. After turning on the air conditioner to "Max", cultures obtained at various intervals revealed that mold concentrations decreased significantly with time. Furthermore, placement of a filter at the portal of entry of outside air significantly reduced the mold concentration in the passenger compartment.

  3. Computational Fluid Dynamics Model for Solar Thermal Storage Tanks with Helical Jacket Heater and Upper Spiral Coil Heater

    Energy Technology Data Exchange (ETDEWEB)

    Baek, Seung Man [Seoul Nat' l Univ., Seoul (Korea, Republic of); Zhong, Yiming; Nam, Jin Hyun [Daegu Univ., Daegu (Korea, Republic of); Chung, Jae Dong [Sejong Univ., Seoul (Korea, Republic of); Hong, Hiki [Kyung Hee Univ., Seoul (Korea, Republic of)

    2013-04-15

    In a solar domestic hot water (Shadow) system, solar energy is collected using collector panels, transferred to a circulating heat transfer fluid (brine), and eventually stored in a thermal storage tank (Test) as hot water. In this study, a computational fluid dynamics (CAD) model was developed to predict the solar thermal energy storage in a hybrid type Test equipped with a helical jacket heater (mantle heat exchanger) and an immersed spiral coil heater. The helical jacket heater, which is the brine flow path attached to the side wall of a Test, has advantages including simple system design, low brine flow rate, and enhanced thermal stratification. In addition, the spiral coil heater further enhances the thermal performance and thermal stratification of the Test. The developed model was validated by the good agreement between the CAD results and the experimental results performed with the hybrid-type Test in Shadow settings.

  4. Computational Fluid Dynamics Model for Solar Thermal Storage Tanks with Helical Jacket Heater and Upper Spiral Coil Heater

    International Nuclear Information System (INIS)

    Baek, Seung Man; Zhong, Yiming; Nam, Jin Hyun; Chung, Jae Dong; Hong, Hiki

    2013-01-01

    In a solar domestic hot water (Shadow) system, solar energy is collected using collector panels, transferred to a circulating heat transfer fluid (brine), and eventually stored in a thermal storage tank (Test) as hot water. In this study, a computational fluid dynamics (CAD) model was developed to predict the solar thermal energy storage in a hybrid type Test equipped with a helical jacket heater (mantle heat exchanger) and an immersed spiral coil heater. The helical jacket heater, which is the brine flow path attached to the side wall of a Test, has advantages including simple system design, low brine flow rate, and enhanced thermal stratification. In addition, the spiral coil heater further enhances the thermal performance and thermal stratification of the Test. The developed model was validated by the good agreement between the CAD results and the experimental results performed with the hybrid-type Test in Shadow settings

  5. An experimental study of the mass flow rates effect on flat-plate solar water heater performance using Al2O3/water nanofluid

    Directory of Open Access Journals (Sweden)

    Prakasam Michael Joseph Stalin

    2017-01-01

    Full Text Available In the present work, flat plate solar water heating system has been designed and fabricated accommodating 2 m2 area of solar collector and 0.12 m2 surface area of the heat exchanger using Al2O3/water nanofluid as the working fluid in order to evaluate the performance efficiency in the forced circulation mode. The instantaneous efficiency of solar collector is calculated by taking lower volume fraction of 0.01% with average particle size of 25 nm with and without Triton X-100 surfactant and varying the flow rate from 1 L per minute to 3 L per minute, as per ASHRAE standard. The experimental results show that utilizing Al2O3/water nanofluid with mass flow rate at 2 L per minute increases the collector efficiency by 14.3% when compared to distilled water as the working medium.

  6. Comparative investigation of thermoelectric air-conditioners versus vapour compression and absorption air-conditioners

    International Nuclear Information System (INIS)

    Riffat, S.B.; Qiu Guoquan

    2004-01-01

    This paper compares the performance of three types of domestic air-conditioners, namely the vapour compression air-conditioner (VCAC), the absorption air-conditioner (AAC) and the thermoelectric air-conditioner (TEAC). The basic cycles of the three types of air-conditioning systems are described and methods to calculate their coefficients of performance are presented. General specification data for each type of air-conditioner are given, and performance characteristics are presented. The comparison shows that although VCACs have the advantages of high COP and low purchase price, use of these systems will be phased out due to their contribution to the greenhouse effect and depletion of the ozone layer. AACs are generally bulky, complex and expensive but operate on thermal energy, so their operational consumption is low. TEACs are environmental friendly, simple and reliable but still very expensive at present. Their low COP is an additional factor limiting their application for domestic cooling. TEACs however, have a large potential market as air-conditioners for small enclosures, such as cars and submarine cabins, where the power consumption would be low, or safety and reliability would be important

  7. Energy performance and consumption for biogas heat pump air conditioner

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Zhenjun [Architectural Engineering College, Qingdao Agricultural University, 266109 (China); Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101 (China); Tianjin University, Tianjin, 300072 (China); Wu, Huaizhi; Wu, Meiling [Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101 (China); Tianjin University, Tianjin, 300072 (China)

    2010-12-15

    Biogas engine-driven heat pump air conditioner is a new-style system which includes biogas engine-driven heat pump, primary heat exchanger, second heat exchanger, sprayed room and fans, pumps, etc. In summertime, the air can be reheated by the waste heat water from the biogas engine in the system, while the air can be reheated and humidified by the waste heat water in winter. Reducing or displacing electrical heating requirements can achieve the great opportunity for significant energy savings. This paper, therefore, aims to improve the energy performance of the AC system by using the waste heat from the biogas engine. The mathematic model was used to research the BHPAC. Explicitly, we investigated the influence of various factors including the outdoor air temperature and humidity in summer and winter. Results show that the biogas engine-driven heat pump air conditioner can save more energy than the electrical power heat pump. In summer, the minimum for percentage of primary energy saving for BHPAC is over 25%. With the outdoor air dry-bulb temperature and the relative humidity rises, the saving energy percentage rises. In winter, the minimum for percentage of primary energy saving for BHPAC is 37%. The more the outdoor air relative humidity of the outdoor air decreases, the more the BHPAC saves energy. It is proved that the system which is a highly actively fully utilizing energy technology has good partial load characteristic and good effects of energy saving. (author)

  8. 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.

  9. Development of a solar powered residential air conditioner (General optimization)

    Science.gov (United States)

    Lowen, D. J.

    1976-01-01

    A commercially available 3-ton residential Lithium Bromide (LiBr) absorption air conditioner was modified for use with lower temperature solar heated water. The modification included removal of components such as the generator, concentration control chamber, liquid trap, and separator; and the addition of a Chrysler designed generator, an off-the-shelf LiBr-solution pump. The design goal of the modified unit was to operate with water as the heat-transfer fluid at a target temperature of 85 C (185 F), 29.4 C (85 F) cooling water inlet, producing 10.5 kW (3 tons) of cooling. Tests were performed on the system before and after modification to provide comparative data. At elevated temperatures (96 C, 205 F), the test results show that Lithium Bromide was carried into the condenser due to the extremely violent boiling and degraded the evaporator performance.

  10. CHARACTERISTICS OF COMPOSTED BIO-TOILET RESIDUE AND ITS POTENTIAL USE AS A SOIL CONDITIONER

    Directory of Open Access Journals (Sweden)

    Jovita Triastuti

    2016-10-01

    Full Text Available Bio-toilet is a dry toilet where human excreta is trapped in a lignocelluloses soil matrix such as wood sawdust, then it is decomposed by aerobic  bacteria to organic compost rich in minerals such as N, P, and K. The study aimed to characterize the bio-toilet residue and its potential use as a soil conditioner for Jatropha curcas. The study was conducted in a private school of Daarut Tauhid in Bandung West Java. A bio-toilet S-50 type of Japan was constructed consisting of a composting chamber, mixer, heater, exhaust fan, and closet. The composting chamber was filled with 63 kg of Albizzia sawdust. Feces and urine was loaded daily by 54 students for 122-day observation. At the end of observation, the decomposed bio-toilet residue was evaluated for its physical properties such as bulk density (rb, porosity (%, and water retention (WR. Chemical properties such as pH, C/N ratio, N, P, and K, as well as microbiological properties such as numbers of bacteria, fungi, and worm eggs were evaluated at 14 and 122 days of decomposition process. Effect of the composted bio-toilet residue as plant growth media was evaluated using J. curcass as a plant indicator. Before it was used as a growth media, the composted bio-toilet residue was dried in a room temperature for 30 days. The experiment was designed in a completely randomized design 2 x 4 factorial with three replications. The first factor was the rate of composted biotoilet residue, i.e., 0, 20, 40, and 60% based on weight of the growth media mixture (1500 g pot-1, and the second was NPK fertilizer addition at 0 and 2 g pot-1. Each pot was planted with 2-month old of J. curcas seedlings. Parameters evaluated were leaf number, leaf area, stem height, and stem diameter measured at 12 weeks after planting. The results showed that the biotoilet residue was suitable as soil conditioner because it had high porosity (76%, low bulk density (0.19 g cm-3, high water retention (2.6 ml g-1 DM, neutral pH (6.9, C

  11. Energy discharge heater power supply

    International Nuclear Information System (INIS)

    Jaskierny, W.

    1992-11-01

    The heater power supply is intended to supply capacitively stored,energy to embedded heater strips in cryo magnets. The amount of energy can be controlled by setting different charge different capacitor values. Two chassis' can be operated in series or interlocks are provided. The charge voltage, number of capacitors pulse can be monitored. There and dual channel has two discharge supplies in one chassis. This report reviews the characteristics of this power supply further

  12. Factor 4 working group: preparing future is urgent. Energy saving certificates. The tax credit boosts the solar water heater and heat pump sales. Climatic change and energy: the Californian example

    International Nuclear Information System (INIS)

    Laverne, R.; Rabany, B.; Leclercq, M.; Lorec, Ph.; Schweitzer, J.Ph.

    2007-01-01

    This issue of 'Energies et Matieres Premieres' newsletter comprises 4 articles dealing with: the concluding report of the 'Factor 4' working group which expresses 28 recommendations in the form of energy policy proposals necessary to be implemented as soon as possible in order for France to start a society and economy transition and to reach the 2050 goal of dividing the present day greenhouse gas emissions by a factor 4; the energy saving certificates implemented with the July 13, 2005 law of energy policy choices, which targets the diffuse energy saving sources in the residential and tertiary sectors; the success of the tax credit for the use of solar thermal water heaters, wood-fuel space heating appliances and air/water and geothermal heat pumps, in particular in the residential sector; the problem of the links between climatic change and energy and the lessons learnt from the example of the 'new sustainable economy' of California (USA). (J.S.)

  13. Research on a compact adsorption room air conditioner

    International Nuclear Information System (INIS)

    Yang, G.Z.; Xia, Z.Z.; Wang, R.Z.; Keletigui, Daou; Wang, D.C.; Dong, Z.H.; Yang, X.

    2006-01-01

    A novel compact adsorption room air conditioner with a cooling capacity of 1 kW has been designed, and two prototypes have been built. A two bed, continuous adsorption refrigeration cycle with heat recovery and mass recovery is adopted. Micropore spherical silica gel and water are selected as the working pair. A gravity heat pipe with methanol as working medium is designed to output the cooling. Experimental investigations have indicated that under typical air conditioning conditions, for the first prototype, a cooling capacity of 687 W and a COP (coefficient of performance) of 0.307 can be obtained. However, for the improved one, a cooling capacity of 790 W and a COP of 0.446 can be reached. It is also proved that the operating temperatures have strong influences on the performance. The designed room air conditioner can be driven by a low grade heat source ( o C) and has small dimensions of 300 mm (depth), 500 mm (width) and 950 mm (height)

  14. Retrofitting Conventional Electric Domestic Hot Water Heaters to Solar Water Heating Systems in Single-Family Houses—Model Validation and Optimization

    Directory of Open Access Journals (Sweden)

    Luis R. Bernardo

    2013-02-01

    Full Text Available System cost reductions and development of standardised plug-and-function systems are some of the most important goals for solar heating technology development. Retrofitting hot water boilers in single-family houses when installing solar collectors has the potential to significantly reduce both material and installation costs. In this study, the TRNSYS simulation models of the retrofitting solar thermal system were validated against measurements. Results show that the validated models are in good agreement with measurements. On an annual basis a deviation of 2.5% out of 1099 kWh was obtained between the auxiliary energy from results and from the simulation model for a complete system. Using the validated model a system optimization was carried out with respect to control strategies for auxiliary heating, heat losses and volume of auxiliary storage. A sensitivity analysis was carried out regarding different volumes of retrofitted hot water boiler, DHW profiles and climates. It was estimated that, with adequate improvements, extended annual solar fractions of 60%, 78% and 81% can be achieved for Lund (Sweden, Lisbon (Portugal and Lusaka (Zambia, respectively. The correspondent collector area was 6, 4 and 3 m2, respectively. The studied retrofitted system achieves a comparable performance with conventional solar thermal systems with the potential to reduce the investment cost.

  15. 蓄能型太阳能热泵热水器性能系数的分析%Coefficient of performance of solar heat pump water heater with energy storage

    Institute of Scientific and Technical Information of China (English)

    吴薇; 卫梁彦; 程清; 王玲珑

    2011-01-01

    To solve the problem that solar heat pump water heater was prone to be affected by weather, a novel water heater integrated with collection, storage and evaporation was proposed. The principle, characteristics, operating modes and structure of the collector-storage-evaporator system were investigated. Using phase change material of decanoic acid to store solar radiation in sunny days as low-temperature source, hot water was produced at night or in continuous rainy days. Thermal efficiency of heat pump system was increased significantly, and the operating unstableness of the heat pump system caused by interval solar energy was also solved. Experiments under different conditions and operating modes in spring were conducted, and the coefficient of performance ( COP) of the system was analyzed. The results indicate that COP of this novel solar heat pump water heater with energy storage is higher than that of ordinary solar heat pump water heater at the same weather condition. The average COP of this system is 7. 56 with maximum of 8. 9 for average solar radiation of 592 W·m-2. COP can also reach 6.4 even at night, which means that weather has slight influence on COP.%针对太阳能热泵热水器受天气变化影响的问题,提出了一种新型的集热-蓄能-蒸发一体化太阳能热泵热水器,给出了系统的原理、特点、运行模式和集热-蓄能-蒸发器的结构形式,以癸酸为相变材料储存晴天的太阳辐射能,作为热泵在夜间和连续阴雨天时的低温热源制得热水,提高了热泵的制热效率,解决了太阳能间歇性所造成的系统运行不稳定的问题.进行了春季不同工况、不同工作模式的试验,分析了系统的性能系数COP,得出该系统的平均COP为7.56.太阳辐射强度均值为592 W·m-2的天气条件下,COP可达8.9;即使在夜间,COP仍能达到6.4,均高于相同天气条件下普通太阳能热泵热水器的COP,该系统的COP受天气变化影响较小.

  16. Simulation Models of Leaf Area Index and Yield for Cotton Grown with Different Soil Conditioners.

    Directory of Open Access Journals (Sweden)

    Lijun Su

    Full Text Available Simulation models of leaf area index (LAI and yield for cotton can provide a theoretical foundation for predicting future variations in yield. This paper analyses the increase in LAI and the relationships between LAI, dry matter, and yield for cotton under three soil conditioners near Korla, Xinjiang, China. Dynamic changes in cotton LAI were evaluated using modified logistic, Gaussian, modified Gaussian, log normal, and cubic polynomial models. Universal models for simulating the relative leaf area index (RLAI were established in which the application rate of soil conditioner was used to estimate the maximum LAI (LAIm. In addition, the relationships between LAIm and dry matter mass, yield, and the harvest index were investigated, and a simulation model for yield is proposed. A feasibility analysis of the models indicated that the cubic polynomial and Gaussian models were less accurate than the other three models for simulating increases in RLAI. Despite significant differences in LAIs under the type and amount of soil conditioner applied, LAIm could be described by aboveground dry matter using Michaelis-Menten kinetics. Moreover, the simulation model for cotton yield based on LAIm and the harvest index presented in this work provided important theoretical insights for improving water use efficiency in cotton cultivation and for identifying optimal application rates of soil conditioners.

  17. 77 FR 28519 - Test Procedure Guidance for Room Air Conditioners, Residential Dishwashers, and Residential...

    Science.gov (United States)

    2012-05-15

    ... Guidance for Room Air Conditioners, Residential Dishwashers, and Residential Clothes Washers: Public... procedures for room air conditioners, residential dishwashers, and residential clothes washers. DATES: DOE...'s existing test procedures for residential room air conditioners, residential dishwashers, and...

  18. Analysis of proposed eco-design requirements for boilers and water heaters. Paper within the framwork of the ''Material Efficiency and Resource Conservation'' (MaRess) Project - Task 14

    Energy Technology Data Exchange (ETDEWEB)

    Barthel, Klaus; Franke, Moritz [Wuppertal Institute for Climate, Environment and Energy, Wuppertal (Germany)

    2009-12-15

    In 2005, the European Union released the EuP Directive focusing on ecodesign requirements for energy-using products (2005/32/EC: EU Parliament and Council of the EU 2005). This directive, also called Ecodesign Directive, is a framework directive establishing a structure in which so-called implementing measures define specific requirements for placing products on the market and/or putting them into service within the internal European market. These requirements can be environmental performance standards (e.g. minimum energy efficiency or emission standards) and labelling or information requirements. Some existing European directives are already declared as being implementing measures of the Ecodesign Directive. Additionally, new implementing measures have been and will further be developed. Product-specific preparatory studies on behalf of the European Commission provide the basis for this. The preparatory studies for boilers (Lot 1) and water heaters (Lot 2) have been conducted from February 2006 to October 2007 by Van Holsteijn en Kemna (VHK). Based on the preparatory studies, the EU Commission has released several working documents (WD) on possible ecodesign requirements for boilers and water heaters at the beginning of 2008. Following these documents, boilers and water heaters comprise gas-fired, oil-fired and electric central heating (CH) (combi-) boilers / dedicated water heaters in combination with capturing solar thermal energy or ambient heat1. The requirements contain basically energy labelling measures, minimum efficiency performance standards and limits on NOx emissions. An ''Ecoboiler Model'' resp. an ''Eco Hot Water Model'' has been elaborated within the preparatory studies. These models are a crucial part of the requirements and allow for calculation of the efficiencies of boilers and water heaters. Since the models have a high degree of complexity, the Federal Environment Agency (UBA) has asked Wuppertal

  19. MHD oxidant intermediate temperature ceramic heater study

    Science.gov (United States)

    Carlson, A. W.; Chait, I. L.; Saari, D. P.; Marksberry, C. L.

    1981-09-01

    The use of three types of directly fired ceramic heaters for preheating oxygen enriched air to an intermediate temperature of 1144K was investigated. The three types of ceramic heaters are: (1) a fixed bed, periodic flow ceramic brick regenerative heater; (2) a ceramic pebble regenerative heater. The heater design, performance and operating characteristics under conditions in which the particulate matter is not solidified are evaluated. A comparison and overall evaluation of the three types of ceramic heaters and temperature range determination at which the particulate matter in the MHD exhaust gas is estimated to be a dry powder are presented.

  20. Arkansas Solar Retrofit Guide. Greenhouses, Air Heaters and Water Heaters.

    Science.gov (United States)

    Skiles, Albert; Rose, Mary Jo

    Solar retrofits are devices of structures designed to be attached to existing buildings to augment their existing heating sources with solar energy. An investigation of how solar retrofits should be designed to suit the climate and resources of Arkansas is the subject of this report. Following an introduction (section 1), section 2 focuses on…

  1. Architecture for Absorption Based Heaters

    Science.gov (United States)

    Moghaddam, Saeed; Chugh, Devesh

    2018-04-24

    An absorption based heater is constructed on a fluid barrier heat exchanging plate such that it requires little space in a structure. The absorption based heater has a desorber, heat exchanger, and absorber sequentially placed on the fluid barrier heat exchanging plate. The vapor exchange faces of the desorber and the absorber are covered by a vapor permeable membrane that is permeable to a refrigerant vapor but impermeable to an absorbent. A process fluid flows on the side of the fluid barrier heat exchanging plate opposite the vapor exchange face through the absorber and subsequently through the heat exchanger. The absorption based heater can include a second plate with a condenser situated parallel to the fluid barrier heat exchanging plate and opposing the desorber for condensation of the refrigerant for additional heating of the process fluid.

  2. Householders' use of storage heaters

    Energy Technology Data Exchange (ETDEWEB)

    Crawshaw, C M; Williams, D I; Steele, L M

    1986-11-01

    An investigation into the understanding and use of storage heater controls was carried out. The general level of satisfaction with storage heating was high (90%) and most people had a reasonable idea of how the system works, what the controls do and of the tariff costs. However, the study did find substantial areas of ignorance; 37% could not say what controls their heater had and 15% did not know what tariff they were on. This lack of knowledge may prevent users getting the best performance from their heating system, resulting in discomfort and large bills.

  3. Air conditioner with three stages of indirect regeneration

    International Nuclear Information System (INIS)

    Worthington, M.N.

    1987-01-01

    An air conditioner is described comprising: a cabinet defining an internal evaporation chamber and having an air inlet and an air outlet; a heat exchanger mounted in the cabinet and defining an air movement path between the air inlet and the air outlet; means for supplying air to be cooled to the air inlet of the cabinet of movement through the air movement path of the heat exchanger in a heat exchanger relationship; air diversion means for continuously diverting some of the air emerging from the air outlet of the cabinet; and means in the evaporation chamber of the cabinet for recirculating spraying water into the chiller tube of the heat exchanger for interacting with the diverted air moving therethrough to evaporatively cool the heat exchanger

  4. Construction of a solar water heater sustainable in the amazon: using the methodology PBL for interaction between engineering courses and high schools

    Directory of Open Access Journals (Sweden)

    Patricia Mota Milhomem

    2015-12-01

    Full Text Available Across the country is being widely spread the use of energy  renewable, one of the clearest examples of this is to obtain energy by the sun's rays, as well as the latest advances in wind turbine deployment in the South and Northeast. Thus, in order to encourage high school students to engage in the study of science and research development intertwined with energy efficiency. The Laboratório de Engenhocas (hereafter, translated: Gadget Lab extension program of the Federal University of Pará (UFPA/CAMTUC, approved projects CNPq (National Council for Scientific and Technological Development in order to insert into in state high schools of the municipality the methodology PBL (Project Based Learning in order teach the students to learn, be proactive and spark interest in the field of applied sciences. Thus, students sought to develop activities that contribute to minimize the problems of society, thus, was the built and implemented a Low Cost Solar Heater in a single family residence Tucuruí where it was possible to analyze its feasibility and efficiency.

  5. Build Your Own Solar Air Heater.

    Science.gov (United States)

    Conservation and Renewable Energy Inquiry and Referral Service (DOE), Silver Spring, MD.

    The solar air heater is a simple device for catching some of the sun's energy to heat a home. Procedures for making and installing such a heater are presented. Included is a materials list, including tools needed for constructing the heater, sources for obtaining further details, and a list of material specifications. (JN)

  6. 16 CFR Appendix E to Part 305 - Room Air Conditioners

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Room Air Conditioners E Appendix E to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULE... Appendix E to Part 305—Room Air Conditioners Range Information Manufacturer's rated cooling capacity in Btu...

  7. 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.

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

    Science.gov (United States)

    Toffoli, Valeria; Carrato, Sergio; Lee, Dongkyu; Jeon, Sangmin; Lazzarino, Marco

    2013-01-01

    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.

  9. Safety grade pressurizer heater power supply connector assembly

    International Nuclear Information System (INIS)

    Burnett, J.M.; Daftari, R.M.; Reyns, R.M.

    1987-01-01

    This patent describes a pressurizer heater power supply connector assembly for attaching a power cable to an electric heater within a pressurizer of a pressurized water nuclear reactor system, the electric heater having pin contacts. The assembly comprises: a pin-socket type connector including a tubular body having a first open end carrying a pin-socket contact member and an insert intermediate a shell and the pin-socket contact member, the contact member having socket means for electrically receiving and contacting the pin contacts, and a second open end; a flexible sealed conduit including a flexible corrugated tube having one end connected to the second open end of the pin-socket type connector, and another end; and a shop splice assembly including a header adapter and a hose clamp interconnected between the header adapter and another end of the flexible corrugated tube

  10. DEVELOPMENT OF TECHNICAL DECISIONS FOR HEAT SUPPLY WITH TUBULAR GAS HEATERS

    Directory of Open Access Journals (Sweden)

    IRODOV V. F.

    2017-05-01

    Full Text Available Annotation. Problems formulation. The problem that is solved is the development of autonomous heat supply systems that reduce the capital costs of construction and increase the efficiency of the use of energy resources. One of the ways to solve this problem is the use of tubular gas heaters. For this, it is necessary to develop new technical solutions for heat supply with tubular gas heaters, as well as scientific and methodological support for the development, construction and operation of heat supply systems with tubular gas heaters. Analysis of recent research. Preliminary studies of infrared tubular gas heaters are considered, which were used to heat industrial enterprises with sufficiently high premises. The task was to extend the principles of heat supply by means of tubular heaters for heating air, water and heating medium in relatively low rooms. Goal and tasks. To lay out the development of technical solutions for heat supply with tubular gas heaters, which increase the efficiency and reliability of heat supply systems and extend the use of tubular gas heaters in heat supply. Results. Technical solutions for heat supply with tubular gas heaters have made it possible to extend their applications for heating air, water and heating medium in relatively low rooms. Scientific novelty. New technical solutions for heat supply with tubular gas heaters increase the efficiency of using fuel and energy resources at low capital costs. Practical significance. Technical solutions for heat supply using tubular heaters have the potential for wide application in the heat supply of industrial, public and residential facilities. Conclusions. For two decades, new technical solutions for heat supply with tubular gas heaters have been developed, which increase the efficiency and reliability of heat supply systems and can be widely used for autonomous heating.

  11. Effect of Agri-SC as a soil conditioner on runoff, soil loss and crust ...

    African Journals Online (AJOL)

    This study was carried out to determine the effect of Agri-SC as a soil conditioner at different doses (0, 18.50, 37.00, 55.50 and 74.00 l ha-1) on water erosion and crust strengths under laboratory conditions with three replicates. The Agri-SC solutions were sprayed and two consecutive simulated rainfalls (60 mm h-1) were ...

  12. Physical Properties of Sandy Soil Affected by Soil Conditioner Under Wetting and Drying cycles

    Directory of Open Access Journals (Sweden)

    M.I. Choudhary

    1998-06-01

    Full Text Available Information on the effectiveness of soil conditioners over a prolonged period is scarce. A laboratory experiment was undertaken to evaluate the effectiveness of a polyacrylamide (Broadleaf P4 soil conditioner on the physical properties of sandy soil subjected to wetting and drying cycles. Four concentrations of Broadleaf P4 0, 0.2, 0.4, and 0.6% on dry weight basis were uniformly mixed with a calcareous sandy soil. Addition of Broadleaf P4 to sandy soil increased the water holding capacity, decreased the bulk density, and increased the porosity and void ratio at 0 and 16 wetting and drying cycles. The coefficient of linear extensibility increased considerably with increasing concentrations of the polymer. The addition of polymer at 0 and 16 cycles increased considerably the retention and availability of water in sandy soil. Saturated hydraulic conductivity decreased with increasing concentrations of Broadleaf P4 whereas unsaturated hydraulic conductivity at 0 and 16 cycles showed an increase with increasing soil moisture contents. After I6 wetting and drying cycles, the capacity of the soil to hold water was lost on average by 15.8% when compared to the 0 wetting and drying cycle. The effectiveness of the soil conditioner on bulk density, coefficient of linear extensibility, available water and saturated hydraulic conductivity was reduced on average by 14.1, 24.5, 21.l and 53.7% respectively. The significant changes in soil properties between 0 and 16 cycles suggested that the effectiveness of the conditioner decreased with the application of wetting and drying cycles. However, its effect was still considerable when compared to untreated soil under laboratory conditions.

  13. 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.

  14. Effects of a non-rinse conditioner on the enamel of primary teeth

    Directory of Open Access Journals (Sweden)

    Fava Marcelo

    2003-01-01

    Full Text Available The aim of this in vitro study was to evaluate by scanning electron microscopy the morphological aspects of the enamel of primary teeth after etching with 36% phosphoric acid or a non-rinse conditioner. Ten naturally exfoliated anterior primary teeth were selected. The samples were subjected to prophylaxis with pumice paste and water using a low-speed hand piece. Etching was done on the buccal surface. Specimens were divided into 2 groups: G1 (n=10: etching with 36% phosphoric acid gel - Conditioner 36 (Dentsply for 20 s, followed by water rinse for 15 s; G2 (n=10: etching with NRC - Non Rinse Conditioner (Dentsply for 20 s, followed by air drying for 15 s. The samples were dehydrated, mounted on metal stubs, coated with gold and observed with Jeol JSM-6100 scanning electron microscope. Electron-micrographic analysis showed that both etching agents were effective for etching the enamel of primary teeth causing the formation of microporosities on the enamel surface, although the etching pattern was more effective with the use of 36% phosphoric acid gel.

  15. [Gohieria fusca found in dust of air-conditioner filters].

    Science.gov (United States)

    Qiang, Chai; Xiao-Dong, Zhan; Wei, Guo; Chao-Pin, Li

    2017-09-25

    To investigate the pollution status of Gohieria fusca in the air conditioner-filters of different places in Wuhu City. The dust samples were collected from the filters of air-conditioners in dining rooms, shopping malls, hotels and households between June and September, 2013, and G. fusca was detected in the dust samples. There were 430 dust samples collected and 98 were G. fusca positive with the breeding rate of 22.79%. The difference of breeding rates of G. fusca were statistically significant among the different places ( χ 2 =18.294, P air-conditioner filters in Wuhu City gravely.

  16. Feedwater heater performance evaluation using the heat exchanger workstation

    International Nuclear Information System (INIS)

    Ranganathan, K.M.; Singh, G.P.; Tsou, J.L.

    1995-01-01

    A Heat Exchanger Workstation (HEW) has been developed to monitor the condition of heat exchanging equipment power plants. HEW enables engineers to analyze thermal performance and failure events for power plant feedwater heaters. The software provides tools for heat balance calculation and performance analysis. It also contains an expert system that enables performance enhancement. The Operation and Maintenance (O ampersand M) reference module on CD-ROM for HEW will be available by the end of 1995. Future developments of HEW would result in Condenser Expert System (CONES) and Balance of Plant Expert System (BOPES). HEW consists of five tightly integrated applications: A Database system for heat exchanger data storage, a Diagrammer system for creating plant heat exchanger schematics and data display, a Performance Analyst system for analyzing and predicting heat exchanger performance, a Performance Advisor expert system for expertise on improving heat exchanger performance and a Water Calculator system for computing properties of steam and water. In this paper an analysis of a feedwater heater which has been off-line is used to demonstrate how HEW can analyze the performance of the feedwater heater train and provide an economic justification for either replacing or repairing the feedwater heater

  17. Power conditioner without isolation transformer; Toransuresu power conditioner no shohin kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Okado, C; Itami, T; Kimoto, K [Toshiba Corp., Tokyo (Japan)

    1996-10-27

    A light-weight downsized and high efficiency transformer-less type 4 kW power conditioner (inverter) has been developed. This power conditioner insures the system interconnection protection by monitoring the voltage of two single-phase three-line circuits. The power conditioner has weight of 17.5 kg and efficiency of 94%. Potential fluctuation of photovoltaic cells due to the switching of power devices at the inverter was reduced. Output capacity was reduced in the low input voltage range. Outflow of DC component was prevented in high accuracy by usually correcting the zero point drift of detector, and by using the current detector with excellent linearity. To detect the DC ground fault, and to trip the output side breaker locating at the ground fault current pass, a zero phase converter detection circuit has been developed, by which the DC component can be detected at the DC input side. As a result of performance verification, the efficiency, power factor, EMI level, protection of outflow of DC component, protection of ground fault, protection of single operation detection, and noise level were satisfied. This system is prospective for the diffusion of photovoltaic power generation in the future. 3 refs., 8 figs., 1 tab.

  18. Ventilation air conditioner for a reactor container

    International Nuclear Information System (INIS)

    Ikegame, Noboru; Nakagawa, Takeshi.

    1980-01-01

    Purpose: To suppress the variations in the internal pressure of a reactor container and smoothly ventilate the reactor container. Constitution: The air conditioner provides an air-flow-rate-control damper, a purge-air supply fan, and a filter device in the air-supply pipe of a reactor container. Furthermore, it provides a pressure difference detector at a part of the container. The air-flow-rate-control damper is connected electrically through a position-modulator-comparison amplifier to the pressure difference detector. When the filtration becomes insufficient by clogging of the filter device and the internal pressure increased abruptly in the container, the pressure-difference detector can detect it, and the damper is operated by a pressure regulator and the comparator so as to control the air flow to the container. Thus, the internal pressure variation is controlled so as to easily ventilate the container. (J.P.N.)

  19. Requirements of office air conditioners. Pt. 1

    Energy Technology Data Exchange (ETDEWEB)

    Radtke, W

    1988-01-01

    New building designs and experiences gained in the past are reponsible for the considerable changes the requirements of air conditioners have gone through in recent years. Details are given on an exemplary air conditioning system designed for the Colonia Insurances building complex located in the city of Cologne. The ventilation requirements and hygienic conditions set out for air conditioned rooms call for outside air supplies, the careful selection of air intakes, and the filtering of intake air. Details are given on the efficiency and limits of combined natural window ventilation/artificial ventilation systems, the influence of window types, and the influence of building structures. The pressure conditions to be expected for larger building complexes in the case of natural ventilation should be assessed with the help of models put to wind tunnel tests.

  20. Biogas Digester with Simple Solar Heater

    Directory of Open Access Journals (Sweden)

    Kh S Karimov

    2012-10-01

    Full Text Available 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 tank were also included in the calculations. The biogas digester consisted of a methane tank with built-in solar reverse absorber heater to harness the radiant solar energy for heating the slurry comprising of different organic wastes (dung, sewage, food wastes etc.. The methane tank was initially filled to 70% of its volume with organic wastes from the GIK institute’s sewage. The remaining volume was filled with sewage and cow dung from other sources. During a three month period (October-December, 2009 and another two month period (February-March, 2010, the digester was investigated. The effects of solar radiation on the absorber, the slurry’s temperature, and the ambient temperature were all measured during these investigations. It was found that using sewage only and sewage with cow dung in the slurry resulted in retention times of four and two weeks, respectively. The corresponding biogas produced was 0.4 m3 and 8.0 m3, respectively. Finally, this paper also elaborates on the upgradation of biogas through the removal of carbon dioxide, hydrogen sulphide and water vapour, and also the process of conversion of biogas energy into electric powerABSTRAK: Kajian ini membentangkan rekabentuk, fabrikasi dan penyelidikan tentang pencerna biogas dengan pemanas solar ringkas. Sebagai pemanas solar, ia dilengkapkan dengan penyerap pemanas beralik. Suhu maksimum(50oC di dalam tangki metana telah diambil sebagai parameter utama rekabentuk pencerna. Dengan menggunakan

  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)

    V. Kochkin, M. Sweet

    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. Experimental investigation of the performance of an elbow-bend type heat exchanger with a water tube bank used as a heater or cooler in alpha-type Stirling machines

    Energy Technology Data Exchange (ETDEWEB)

    El-Ehwany, A.A.; Hennes, G.M. [Mech. Power Dept., Faculty of Eng., Ain Shams University, Cairo (Egypt); Eid, E.I. [Mech. Dept., Faculty of Ind. Education, Suez Canal University, Suez 43515 (Egypt); El-Kenany, E. [The Specialized Studies Academy, Workers University, Tech. Dept., Mansura (Egypt)

    2011-02-15

    In this work the effect of the elbow-bend geometry and the effect of the tube arrangement on the performance of air-to-water heat exchanger is studied experimentally. In elbow-bend heat exchanger, the direction of the working fluid is bended at 90 degrees to its inlet direction. The heating or cooling fluid flows inside straight tubes while the working fluid flows past the tubes along an elbow pass. Three different types of the geometry of the elbow with three different tube bank arrangements were studied. The results were plotted and analyzed to clarify the effects of the elbow-bend geometry, the tube bank arrangements and the dead volume in the heat exchanger on the heat transfer and pressure drop. Two empirical correlations were deduced for each design, one to predict the relation between Nusselt and Reynolds numbers, while the other relation is between the friction factor and Reynolds number. This work was done to select the more suitable design to be used as a heater or a cooler in Stirling machines. (author)

  3. Statistical analysis of the count and profitability of air conditioners.

    Science.gov (United States)

    Rady, El Houssainy A; Mohamed, Salah M; Abd Elmegaly, Alaa A

    2018-08-01

    This article presents the statistical analysis of the number and profitability of air conditioners in an Egyptian company. Checking the same distribution for each categorical variable has been made using Kruskal-Wallis test.

  4. Parallel heater system for subsurface formations

    Science.gov (United States)

    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.

  5. Lemongrass-Incorporated Tissue Conditioner Against Candida albicans Culture

    Science.gov (United States)

    Amornvit, Pokpong; Srithavaj, Theerathavaj

    2014-01-01

    Background: Tissue conditioner is applied popularly with dental prosthesis during wound healing process but it becomes a reservoir of oral microbiota, especially Candida species after long-term usage. Several antifungal drugs have been mixed with this material to control fungal level. In this study, lemongrass essential oil was added into COE-COMFORT tissue conditioner before being determined for anti-Candida efficacy. Materials and Methods: Lemongrass (Cymbopogon citratus) essential oil was primarily determined for antifungal activity against C. albicans American type culture collection (ATCC) 10231 and MIC (minimum inhibitory concentration) value by agar disk diffusion and broth microdilution methods, respectively. COE-COMFORT tissue conditioner was prepared as recommended by the manufacturer after a fixed volume of the oil at its MIC or higher concentrations were mixed thoroughly in its liquid part. Antifungal efficacy of the tissue conditioner with/without herb was finally analyzed. Results: Lemongrass essential oil displayed potent antifungal activity against C. albicans ATCC 10231and its MIC value was 0.06% (v/v). Dissimilarly, the tissue conditioner containing the oil at MIC level did not cease the growth of the tested fungus. Both reference and clinical isolates of C. albicans were completely inhibited after exposed to the tissue conditioner containing at least 0.25% (v/v) of the oil (approximately 4-time MIC). The tissue conditioner without herb or with nystatin was employed as negative or positive control, respectively. Conclusion: COE-COMFORT tissue conditioner supplemented with lemongrass essential oil obviously demonstrated another desirable property as in vitro anti-Candida efficacy to minimize the risk of getting Candidal infection. PMID:25177638

  6. 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

  7. SINGLE HEATER TEST FINAL REPORT

    International Nuclear Information System (INIS)

    J.B. Cho

    1999-01-01

    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 and 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 not just to the hardware, but also to the teamwork and cooperation between

  8. Small scale heater tests in argillite of the Eleana Formation at the Nevada Test Site

    International Nuclear Information System (INIS)

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

    1979-11-01

    Near-surface heater tests were run in the Eleana Formation at the Nevada Test Site, in an effort to evaluate argillaceous rock for nuclear waste storage. The main test, which employed a full-scale heater with a thermal output approximating commercial borosilicate waste, was designed to operate for several months. Two smaller, scaled tests were run prior to the full-scale test. This report develops the thermal scaling laws, describes the pretest thermal and thermomechanical analysis conducted for these two tests, and discusses the material properties data used in the analyses. In the first test, scaled to a large heater of 3.5 kW power, computed heater temperatures were within 7% of measured values for the entire 96-hour test run. The second test, scaled to a large heater having 5.0 kW power, experienced periodic water in-flow onto the heater, which tended to damp the temperature. For the second test, the computed temperatures were within 7% of measured for the first 20 hours. After this time, the water effect became significant and the measured temperatures were 15 to 20% below those predicted. On the second test, rock surface spallation was noted in the bore hole above the heater, as predicted. The scaled tests indicated that in-situ argillite would not undergo major thermostructural failure during the follow-on, 3.5 kW, full-scale test. 24 figures, 6 tables

  9. Distributed Nonstationary Heat Model of Two-Channel Solar Air Heater

    International Nuclear Information System (INIS)

    Klychev, Sh. I.; Bakhramov, S. A.; Ismanzhanov, A. I.; Tashiev, N.N.

    2011-01-01

    An algorithm for a distributed nonstationary heat model of a solar air heater (SAH) with two operating channels is presented. The model makes it possible to determine how the coolant temperature changes with time along the solar air heater channel by considering its main thermal and ambient parameters, as well as variations in efficiency. Examples of calculations are presented. It is shown that the time within which the mean-day efficiency of the solar air heater becomes stable is significantly higher than the time within which the coolant temperature reaches stable values. The model can be used for investigation of the performances of solar water-heating collectors. (authors)

  10. Discussion on Boiler Efficiency Correction Method with Low Temperature Economizer-Air Heater System

    Science.gov (United States)

    Ke, Liu; Xing-sen, Yang; Fan-jun, Hou; Zhi-hong, Hu

    2017-05-01

    This paper pointed out that it is wrong to take the outlet flue gas temperature of low temperature economizer as exhaust gas temperature in boiler efficiency calculation based on GB10184-1988. What’s more, this paper proposed a new correction method, which decomposed low temperature economizer-air heater system into two hypothetical parts of air preheater and pre condensed water heater and take the outlet equivalent gas temperature of air preheater as exhaust gas temperature in boiler efficiency calculation. This method makes the boiler efficiency calculation more concise, with no air heater correction. It has a positive reference value to deal with this kind of problem correctly.

  11. Experimental Analysis of the Thermo-Hydraulic Performance on a Cylindrical Parabolic Concentrating Solar Water Heater with Twisted Tape Inserts in an Absorber Tube

    Science.gov (United States)

    Kumar, Birendra; Nayak, Rajen Kumar; Singh, S. N.

    2018-05-01

    A twisted tape inserted in an absorber tube may be an excellent option to enhance the performance of a cylindrical parabolic concentrating solar collector (CPC). The present work is an experimental study of the flow and heat transfer with and without twisted tape inserts in the absorber tube of a CPC. Results are presented for mass flow rates of water, ṁ=0.0198-0.0525 kg/s, twist ratio, y=5-10 and Reynolds number, Re=2577.46-6785.55. In the present study, we found that the outlet water temperature, collector efficiency and Nusselt number (Nu) are higher in the twisted tapes as compared to those without the twisted tape inserts in the absorber tube of the CPC. For fixed mass flow rate of water ṁ, the To and η increased with the decrease in twist ratio, y, and is higher in lower twist ratio, y=5, of the twisted tapes. The whole experiment was performed at the Indian Institute of Technology (ISM) in Dhanbad, India during the months of March-April 2017. Based on the experimental data, the correlations for the Nu and friction factor were also developed.

  12. Heater for Combustible-Gas Tanks

    Science.gov (United States)

    Ingle, Walter B.

    1987-01-01

    Proposed heater for pressurizing hydrogen, oxygen, or another combustible liquid or gas sealed in immersion cup in pressurized tank. Firmly supported in finned cup, coiled rod transfers heat through liquid metal to gas tank. Heater assembly welded or bolted to tank flange.

  13. Buffer mass test - Heater design and operation

    International Nuclear Information System (INIS)

    Nilsson, J.; Ramqvist, G.; Pusch, R.

    1984-06-01

    The nuclear waste is assumed to be contained in cylindrical metal canisters which will be inserted in deposition holes. Heat is generated as a result of the continuing decay of the radioactive waste and in the Buffer Mass Test (BMT) the heat flux expected from such canisters was simulated by the use of six electric heaters. the heaters were constructed partly of aluminium and partly of stainless steel. They are 1520 mm in length and 380 mm in diameter, and give a maximum power output of 3000 W. The heater power can be monitored by panel meters coupled to a computer-based data acquisition system. Both the heater and the control system were manufactured with a high degree of redundancy in case of component failure. This report describes the design, construction, testing, installation and necessary tools for heater installation and dismantling operation. (author)

  14. Orbiting compressor for residential air-conditioners

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Jin; Kim, Woo Young; Ahn, Jong Min [Department of Mechanical Engineering, University of Incheon, 12-1 Songdo-dong, Yeonsu-gu, Incheon 406-840 (Korea)

    2010-01-15

    A new type of compressor, called an orbiting compressor, is introduced in this paper. The orbiting compressor is characterized by an orbiting piston, and the piston or orbiter consists of a circular base plate and a ring type vane protruding vertically from the base plate. The orbiter is made to orbit in an annular space formed between two concentric circular walls via an Oldham-ring mechanism, producing two sealed gas pockets on both sides of the vane wrap with a 180 phase difference. This operating mechanism leads to alternating compression and discharge processes, which results in low torque variation. The orbiting compressor has been designed for an R410A residential air conditioner with a cooling capacity of 10.0 kW. The performance of the orbiting compressor model has been analytically investigated, where the volumetric, adiabatic and mechanical efficiencies were calculated to be 94.8%, 90.4% and 93.4%, respectively for the ARI condition. The EER was estimated to be about 10.86 with a motor efficiency of 89%. (author)

  15. High efficiency novel window air conditioner

    International Nuclear Information System (INIS)

    Bansal, Pradeep

    2015-01-01

    Highlights: • Use of novel refrigerant mixture of R32/R125 (85/15% molar conc.) to reduce global warming and improve energy efficiency. • Use of novel features such as electronically commuted motor (ECM) fan motor, slinger and sub-merged sub-cooler. • Energy savings of up to 0.1 Quads per year in USA and much more in Asia/Middle East where WACs are used in large numbers. • Payback period of only 1.4 years of the novel efficient WAC. - Abstract: This paper presents the results of an experimental and analytical evaluation of measures to raise the efficiency of window air conditioners (WAC). In order to achieve a higher energy efficiency ratio (EER), the original capacity of a baseline R410A unit was reduced by replacing the original compressor with a lower capacity but higher EER compressor, while all heat exchangers and the chassis from the original unit were retained. Subsequent major modifications included – replacing the alternating current fan motor with a brushless high efficiency electronically commutated motor (ECM) motor, replacing the capillary tube with a needle valve to better control the refrigerant flow and refrigerant set points, and replacing R410A with a ‘drop-in’ lower global warming potential (GWP) binary mixture of R32/R125 (85/15% molar concentration). All these modifications resulted in significant enhancement in the EER of the baseline WAC. Further, an economic analysis of the new WAC revealed an encouraging payback period

  16. Pulmonary functions in air conditioner users.

    Science.gov (United States)

    Khaliq, Farah; Sharma, Sameer; Tandon, O P

    2006-01-01

    Air conditioning may affect human health since it has profound effect on our environment, than just lowering temperature. The present study was planned to assess the effect of air conditioners (AC) on pulmonary functions in young healthy non-smoker males. The study group comprised of ten subjects who were using AC's in their cars for at least 1 hr daily since last 6 months. While ten subjects who did not use AC at all served as controls. The pulmonary functions were assessed using PK Morgan 232 spirometer in a closed room. The peak expiratory flow rate (PEFR) and Forced expiratory flow between 25-75% of vital capacity (FEF25-75) were significantly reduced in subjects using car AC's. Inspiratory flow rates also showed a trend towards decline in AC users but could not reach the level of significance. The lung volumes and capacities were not significantly different in the two groups except for forced expiratory volume in 0.5 sec (FEV 0.5 sec), which also decreased in AC users. The airway resistance and lung compliance did not show significant change. In the presence of normal FEV1, reduced FEF25-75% which is the flow rate over the middle half of vital capacity, is an evidence of mild airflow limitation. The result is suggestive of predisposition of AC users towards respiratory disorders in form of mild airflow restriction.

  17. Embedding quantum into classical: contextualization vs conditionalization.

    Directory of Open Access Journals (Sweden)

    Ehtibar N Dzhafarov

    Full Text Available We compare two approaches to embedding joint distributions of random variables recorded under different conditions (such as spins of entangled particles for different settings into the framework of classical, Kolmogorovian probability theory. In the contextualization approach each random variable is "automatically" labeled by all conditions under which it is recorded, and the random variables across a set of mutually exclusive conditions are probabilistically coupled (imposed a joint distribution upon. Analysis of all possible probabilistic couplings for a given set of random variables allows one to characterize various relations between their separate distributions (such as Bell-type inequalities or quantum-mechanical constraints. In the conditionalization approach one considers the conditions under which the random variables are recorded as if they were values of another random variable, so that the observed distributions are interpreted as conditional ones. This approach is uninformative with respect to relations between the distributions observed under different conditions because any set of such distributions is compatible with any distribution assigned to the conditions.

  18. Feasibility study on novel room air conditioner with natural cooling capability

    International Nuclear Information System (INIS)

    Han, Zongwei; Liu, Qiankun; Zhang, Yanqing; Zhang, Shuwei; Liu, Jiangzhen; Li, Weiliang

    2016-01-01

    Highlights: • A novel heat pipe combined evaporative cooling room air conditioner is constructed. • The mathematical model of the air conditioner is established. • The reliability of the model is verified by experiments. • The performance of the novel and conventional air conditioner is compared. • The applicability of the novel air conditioner in different areas is investigated. - Abstract: In order to improve the energy efficiency of room air conditioners, this paper proposed a new air conditioner that combined evaporative cooling technology, separate type heat pipe technology, and vapour compression refrigeration technology (called “combined air conditioner”). The mathematical model of the air conditioner was established and its reliability was verified by experiments. Based on the model, the simulation of the operating performance of the combined air conditioner and a conventional air conditioner was studied in typical climate regions during the cooling period, with the following results: In cold and dry areas like Shenyang, compared with the conventional air conditioner, the average cooling coefficient of performance (COP) of the combined air conditioner was increased by 27.40%. As the climate gradually became warmer and humidity gradually increased, the running time of the heat pipe cooling mode was gradually reduced, and then the energy-saving effect of the combined air conditioner became worse. For example, in the hot and humid Guangzhou, the energy saving rate was only 11.81%. Therefore, it was found that the combined air conditioner had good energy-saving potential in cold and dry areas.

  19. Spectra of conditionalization and typicality in the multiverse

    Science.gov (United States)

    Azhar, Feraz

    2016-02-01

    An approach to testing theories describing a multiverse, that has gained interest of late, involves comparing theory-generated probability distributions over observables with their experimentally measured values. It is likely that such distributions, were we indeed able to calculate them unambiguously, will assign low probabilities to any such experimental measurements. An alternative to thereby rejecting these theories, is to conditionalize the distributions involved by restricting attention to domains of the multiverse in which we might arise. In order to elicit a crisp prediction, however, one needs to make a further assumption about how typical we are of the chosen domains. In this paper, we investigate interactions between the spectra of available assumptions regarding both conditionalization and typicality, and draw out the effects of these interactions in a concrete setting; namely, on predictions of the total number of species that contribute significantly to dark matter. In particular, for each conditionalization scheme studied, we analyze how correlations between densities of different dark matter species affect the prediction, and explicate the effects of assumptions regarding typicality. We find that the effects of correlations can depend on the conditionalization scheme, and that in each case atypicality can significantly change the prediction. In doing so, we demonstrate the existence of overlaps in the predictions of different "frameworks" consisting of conjunctions of theory, conditionalization scheme and typicality assumption. This conclusion highlights the acute challenges involved in using such tests to identify a preferred framework that aims to describe our observational situation in a multiverse.

  20. Analisis Termal High Pressure Feedwater Heater di PLTU PT. XYZ

    Directory of Open Access Journals (Sweden)

    Maria Ulfa Damayanti

    2017-01-01

    Full Text Available Abstrak- PT. XYZ mengoperasikan tiga unit Pembangkit Listrik Tenaga Uap (PLTU unit 3, 7 dan 8 berkapasitas 2.030 MegaWatt. Pada PLTU Paiton unit 7 dan 8 terdapat delapan buah feedwater heater yaitu empat buah Low Pressure Water Heater (LPWH, tiga buah High Pressure Water Heater (HPWH, dan sebuah dearator. Pada PLTU Paiton unit 7 dan 8 terdapat kerusakan pada HPWH 6 yang menyebabkan penurunan efisiensi dari siklus secara keseluruhan. Penurunan efisiensi dapat terjadi karena temperatur feedwater sebelum masuk ke boiler terlalu rendah, sehingga kalor yang dibutuhkan oleh boiler untuk memanaskan feedwater meningkat. Oleh karena itu konsumsi batubara akan meningkat dan menyebabkan terjadi kenaikan biaya operasional harian dalam sistem pembangkit. Dari data Divisi Produksi PT. XYZ Unit 7 dan 8 diperoleh spesifikasi HPWH 6, 7, dan 8 dan propertis fluida dalam HPWH 6, 7, dan 8. Data tersebut digunakan sebagai dasar analisis termal yang meliputi performa masing-masing HPH. Tahap selanjutnya dalam analisis termal adalah memvariasikan beban 25%, 50%, 75%, 100%, dan 105%. Tahap terakhir analisis adalah menghitung performa dengan variasi sumbatan (plug 5%, 10%, 15%, dan 20% sesuai dengan variasi beban. Hasil yang didapatkan dari penelitian tugas akhir ini adalah nilai effectiveness tertinggi tercapai pada pembebanan 100% serta menghasilkan pressure drop tertinggi pada pembebanan 105%, nilai effectiveness terbesar serta nilai pressure drop terkecil terjadi pada zona Condensing, serta sumbatan (plugging pada HPH akan menyebabkan penurunan nilai effectiveness dan kenaikan pressure drop sisi tube.

  1. Particulate matter sensor with a heater

    Science.gov (United States)

    Hall, Matthew [Austin, TX

    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.

  2. 77 FR 8178 - Test Procedures for Central Air Conditioners and Heat Pumps: Public Meeting

    Science.gov (United States)

    2012-02-14

    .... EERE-2010-BT-TP-0038] Test Procedures for Central Air Conditioners and Heat Pumps: Public Meeting... methodologies and gather comments on testing residential central air conditioners and heat pumps designed to use... residential central air conditioners and heat pumps that are single phase with rated cooling capacities less...

  3. 48 CFR 52.223-12 - Refrigeration Equipment and Air Conditioners.

    Science.gov (United States)

    2010-10-01

    ... and Air Conditioners. 52.223-12 Section 52.223-12 Federal Acquisition Regulations System FEDERAL... Provisions and Clauses 52.223-12 Refrigeration Equipment and Air Conditioners. As prescribed in 23.804(b), insert the following clause: Refrigeration Equipment and Air Conditioners (MAY 1995) The Contractor shall...

  4. 16 CFR 305.12 - Labeling for central air conditioners, heat pumps, and furnaces.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Labeling for central air conditioners, heat... (âAPPLIANCE LABELING RULEâ) Required Disclosures § 305.12 Labeling for central air conditioners, heat pumps, and furnaces. (a) Layout. All energy labels for central air conditioners, heat pumps, and...

  5. 75 FR 7987 - Energy Conservation Standards for Residential Clothes Dryers and Room Air Conditioners: Public...

    Science.gov (United States)

    2010-02-23

    ... Conservation Standards for Residential Clothes Dryers and Room Air Conditioners: Public Meeting and... conservation standards for residential clothes dryers and room air conditioners; the analytical framework..., Mailstop EE-2J, Public Meeting for Residential Clothes Dryers and Room Air Conditioners, EERE-2007-BT-STD...

  6. 10 CFR 431.92 - Definitions concerning commercial air conditioners and heat pumps.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Definitions concerning commercial air conditioners and... PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Commercial Air Conditioners and Heat Pumps § 431.92 Definitions concerning commercial air conditioners and heat pumps. The following definitions apply...

  7. 75 FR 72739 - Compliance Testing Procedures: Correction Factor for Room Air Conditioners

    Science.gov (United States)

    2010-11-26

    ...: Correction Factor for Room Air Conditioners AGENCY: Office of the General Counsel, Department of Energy (DOE... air conditioners. The petition seeks temporary enforcement forbearance, or in the alternative, a... procedures for room air conditioners. Public comment is requested on whether DOE should grant the petition...

  8. 75 FR 14368 - Energy Conservation Standards for Residential Central Air Conditioners and Heat Pumps: Public...

    Science.gov (United States)

    2010-03-25

    ... Conservation Standards for Residential Central Air Conditioners and Heat Pumps: Public Meeting and Availability... conservation standards for residential central air conditioners and heat pumps; the analytical framework..., Mailstop EE-2J, Public Meeting for Residential Central Air Conditioners and Heat Pumps, EERE-2008-BT- STD...

  9. 21 CFR 872.3750 - Bracket adhesive resin and tooth conditioner.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Bracket adhesive resin and tooth conditioner. 872... SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3750 Bracket adhesive resin and tooth conditioner. (a) Identification. A bracket adhesive resin and tooth conditioner is a device...

  10. Temperature measurements from a horizontal heater test in G-Tunnel

    International Nuclear Information System (INIS)

    Lin, Wunan; Ramirez, A.L.; Watwood, D.

    1991-10-01

    A horizontal heater test was conducted in G-Tunnel, Nevada Test Site, to study the hydrothermal response of the rock mass due to a thermal loading. The results of the temperature measurements are reported here. The measured temperatures agree well with a scoping calculation that was performed using a model which investigates the transport of water, vapor, air, and heat in fractured porous media. Our results indicate that the temperature field might be affected by the initial moisture content of the rock, the fractures in the rock, the distance from the free surface of the alcove wall, and the temperature distribution on the heater surface. Higher initial moisture content, higher fracture density, and cooling from the alcove wall tend to decrease the measured temperature. The temperature on top of the horizontal heater can was about 30 degrees C greater than at the bottom throughout most of the heating phase, causing the rock temperatures above the heater to be greater than those below. Along a radius from the center of the heater, the heating created a dry zone, followed by a boiling zone and condensation zone. Gravity drainage of the condensed water in the condensation zone had a strong effect on the boiling process in the test region. The temperatures below and to the side of the heater indicated a region receiving liquid drainage from an overlying region of condensation. We verified that a thermocouple in a thin-wall tubing measures the same temperature as one grouted in a borehole

  11. Microcontroller based instrumentation for heater control circuit of tin oxide based hydrogen sensor

    International Nuclear Information System (INIS)

    Premalatha, S.; Krithika, P.; Gunasekaran, G.; Ramakrishnan, R.; Ramanarayanan, R.R.; Prabhu, E.; Jayaraman, V.; Parthasarathy, R.

    2015-01-01

    A thin film sensor based on tin oxide developed in IGCAR is used to monitor very low levels of hydrogen (concentration ranging from 2 ppm to 80 ppm). The heater and the sensor patterns are integrated on a miniature alumina substrate and necessary electrical leads are taken out. For proper functioning of the sensor, the heater has to be maintained at a constant temperature of 350°C. The sensor output (voltage signal) varies with H 2 concentration. In fast breeder reactors, liquid sodium is used as coolant. The sensor is used to detect water/steam leak in secondary sodium circuit. During the start up of the reactor, steam leak into sodium circuit generates hydrogen gas as a product that doesn't dissolve in sodium, but escapes to the surge tank containing argon i.e. in cover gas plenum of sodium circuit. On-line monitoring of hydrogen in cover gas is done to detect an event of water/steam leakage. The focus of this project is on the instrumentation pertaining to the temperature control for the sensor heater. The tin oxide based hydrogen sensor is embedded in a substrate which consists of a platinum heater, essentially a resistor. There is no provision of embedding a temperature sensor on the heater surface due to the physical constraints, without which maintaining a constant heater temperature is a complex task

  12. Utilização de água salina e condicionador de solo na produção de beterraba no semi-árido brasileiro Effect of saline water and soil conditioner on sugar beet yield in the Brazilian semi-arid region

    Directory of Open Access Journals (Sweden)

    Gilberto G. Cordeiro

    1999-03-01

    Full Text Available O experimento foi conduzido no Campo Experimental da Embrapa Semi-Árido em Petrolina - PE, no primeiro semestre de 1997 com o objetivo de avaliar o efeito de diferentes níveis de salinidade da água de irrigação e do condicionador de solo Sper Sal (ácido polimaléico na produção de beterraba (Beta vulgaris L., cultivar Early Wonder. O delineamento experimental foi de blocos ao acaso com quatro repetições. Os tratamentos foram: água com condutividade elétrica de 0,1 (água do Rio São Francisco - testemunha 4 e 8 dS/m e água com condutividade elétrica 0,1, 4 e 8 dS/m mais Sper Sal, com parcelas de 2 m². Os resultados obtidos mostraram que as produtividades variaram de 20,2 a 65,4 t/ha para os tratamentos irrigados com água salina mais Sper Sal e água do Rio São Francisco, respectivamente. Não se verificou diferença significativa na produtividade quando do uso de água com níveis de salinidade de 4 e 8 dS/m, cujas produtividades foram 29,4 e 26,3 t/ha respectivamente. Nos tratamentos com Sper Sal, observou-se que na concentração salina de 4 dS/m, o condicionador de solo demonstrou ser mais eficiente, em relação à concentração de 8 dS/m.An experiment was carried out at an experimental field in Embrapa Semi-arid, Petrolina - PE, during the first semester of 1997, with the objective of evaluating the effect of different irrigation water salinity levels, with and without the soil conditioner Sper Sal (polymaleic acid, on the yield of sugar beet (Beta vulgaris L., cv. Early Wonder. The experiment was set up in complete randomized block design, with four replications. Six treatments were tested: water with electrical conductivity of 0.1 (control, 4 and 8 dS/m, and the levels of electrical conductivity cited above plus Sper salt. The size of the plots was 2m². The results obtained showed that the yield varied from 20.2 to 65.4 t/ha, respectively, for irrigation treatments of saline with Sper Sal and water from the S

  13. Air-conditioner filters enriching dust mites allergen.

    Science.gov (United States)

    Zhan, Xiaodong; Li, Chaopin; Xu, Haifeng; Xu, Pengfei; Zhu, Haibin; Diao, Jidong; Li, Na; Zhao, Beibei

    2015-01-01

    We detected the concentration of dust mites allergen (Der f1 & Der p1) in the air of different places before and after the starting of air-conditioners in Wuhu City, Anhui, China, and to discuss the relation between the dust mites allergen in air-conditioner filters and the asthma attack. The dust samples were collected from the air-conditioner filters in dining rooms, shopping malls, hotels and households respectively. Concentrations of dust mites major group allergen 1 (Der f 1, Der p1) were detected with enzyme linked immunosorbent assay (ELISA), and the dust mite immune activities were determined by dot-ELISA. The concentration of Der f1 in dining rooms, shopping malls, hotels and households was 1.52 μg/g, 1.24 μg/g, 1.31 μg/g and 1.46 μg/g respectively, and the concentration of Der p1 in above-mentioned places was 1.23 μg/g, 1.12 μg/g, 1.16 μg/g and 1.18 μg/g respectively. The concentration of Der f1 & Der p1 in air was higher after the air-conditioners starting one hours later, and the difference was significant (Pair-conditioner filters can enrich dust mites major group allergen, and the allergens can induce asthma. The air-conditioner filters shall be cleaned or replaced regularly to prevent or reduce accumulation of the dust mites and its allergens.

  14. Control Technologies for Room Air-conditioner and Packaged Air-conditioner

    Science.gov (United States)

    Ito, Nobuhisa

    Trends of control technologies about air-conditioning machineries, especially room or packaged air conditioners, are presented in this paper. Multiple air conditioning systems for office buildings are mainly described as one application of the refrigeration cycle control technologies including sensors for thermal comfort and heating/ cooling loads are also described as one of the system control technologies. Inverter systems and related technologies for driving variable speed compressors are described in both case of including induction motors and brushless DC motors. Technologies for more accurate control to meet various kind of regulations such as ozone layer destruction, energy saving and global warming, and for eliminating harmonic distortion of power source current, as a typical EMC problem, will be urgently desired.

  15. Is your electric process heater safe?

    Energy Technology Data Exchange (ETDEWEB)

    Tiras, C.S.

    2000-04-01

    Over the past 35 years, electric process heaters (EPHs) have been used to heat flowing fluids in different sectors of the energy industry: oil and gas exploration and production, refineries, petrochemical plants, pipeline compression facilities and power-generation plants. EPHs offer several advantages over fired heaters and shell-and-tube exchangers, which have been around for many years, including: smaller size, lighter weight, cleaner operation, lower capital costs, lower maintenance costs, no emissions or leakage, better control and improved safety. However, while many industrial standards have addressed safety concerns of fired heaters and shell-and-tube exchangers (API, TEMA, NFPA, OSHA and NEC), no standards address EPHs. The paper presents a list of questions that plant operators need to ask about the safety of their electric process heaters. The answers are also given.

  16. Design data brochure: Solar hot air heater

    Science.gov (United States)

    1978-01-01

    The design, installation, performance, and application of a solar hot air heater for residential, commercial and industrial use is reported. The system has been installed at the Concho Indian School in El Reno, Oklahoma.

  17. A prototype construction of bearing heater system

    International Nuclear Information System (INIS)

    Firman Silitonga

    2007-01-01

    A bearing heater system has been successfully constructed using transformer-like method of 1000 VA power, 220 V primary voltage, and 50 Hz electrical frequency. The bearing heater consists of primary coil 230 turns, U type and bar-type iron core with 36 cm 2 , 9 cm 2 ,and 3 cm 2 cross-section, and electrical isolation. The bearing heater is used to enlarge the diameter of the bearing so that it can be easily fixed on an electric motor shaft during replacement because the heating is conducted by treated the bearing as a secondary coil of a transformer. This bearing heater can be used for bearing with 3 and 6 cm of inner diameter and 12 cm of maximum outside diameter. (author)

  18. Thermal-mechanical-hydrological-chemical responses in the single heater test at the ESF

    International Nuclear Information System (INIS)

    Lin, W.; Blair, S.; Buettner, M

    1997-01-01

    The Single Heater Test (SHT) is conducted in the Exploratory Studies Facility (ESF) to study the thermal-mechanical responses of the rock mass. A set of boreholes were drilled in the test region for conducting a scoping test of the coupled thermal-mechanical- hydrological-chemical (TMHC) processes. The holes for the TMHC tests include electrical resistivity tomography (ERT), neutron logging/temperature, hydrological, and optical multiple point borehole extensometers. A 4-kW heater was installed in the heater hole, and was energized on August 26, 1996. Some observed movements of the water around the heater are associated with a possible dry-out region near the heater. The water that has been moved is more dilute than the in situ ground water, except for the concentration of Ca. This indicates that fractures are the major water pathways, and the displaced water may have reached an equilibrium with carbonate minerals on the fracture surfaces. No mechanical-hydrological coupling has been observed. The tests are on-going, and more data will be collected and analyzed

  19. Unregulated heat output of a storage heater

    OpenAIRE

    Lysak, Oleg Віталійович

    2017-01-01

    In the article the factors determining the heat transfer between the outer surfaces of a storage heater and the ambient air. This heat exchange is unregulated, and its definition is a precondition for assessing heat output range of this type of units. It was made the analysis of the literature on choosing insulating materials for each of the external surfaces of storage heaters: in foreign literature, there are recommendations on the use of various types of insulation depending on the type of...

  20. Conasauga near-surface heater experiment. Final report

    International Nuclear Information System (INIS)

    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 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

  1. 10 CFR Appendix F to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Room Air Conditioners

    Science.gov (United States)

    2010-01-01

    ... of Room Air Conditioners F Appendix F to Subpart B of Part 430 Energy DEPARTMENT OF ENERGY ENERGY... Conditioners 1. Test method. The test method for testing room air conditioners shall consist of application of the methods and conditions in American National Standard (ANS) Z234.1-1972, “Room Air Conditioners...

  2. Pulmonary function tests in air conditioner users | Vidya ...

    African Journals Online (AJOL)

    Background: Modernization has been implicated in the pathogenesis of allergic airway diseases. House dust, mites, and indoor air pollutants have been reported to cause elevation of serum IgE levels and/or enhancement of eosinophil activity. A component of modern lifestyle is the intense use of air-conditioners (AC) that ...

  3. Design of direct solar PV driven air conditioner

    KAUST Repository

    Huang, Bin-Juine; Hou, Tung-Fu; Hsu, Po-Chien; Lin, Tse-Han; Chen, Yan-Tze; Chen, Chi-Wen; Li, Kang; Lee, K.Y.

    2015-01-01

    ). The measured OPB is found to be greater than 0.98 at instantaneous solar irradiation IT > 600 W m-2 if rpL > 1.71 RF approaches 1.0 (the air conditioner is run in 100% with solar power) at daily-total solar radiation higher than 13 MJ m-2 day-1, if rpL > 3.

  4. Thermionic reactor power conditioner design for nuclear electric propulsion.

    Science.gov (United States)

    Jacobsen, A. S.; Tasca, D. M.

    1971-01-01

    Consideration of the effects of various thermionic reactor parameters and requirements upon spacecraft power conditioning design. A basic spacecraft is defined using nuclear electric propulsion, requiring approximately 120 kWe. The interrelationships of reactor operating characteristics and power conditioning requirements are discussed and evaluated, and the effects on power conditioner design and performance are presented.

  5. Domestic Refrigeration, Freezer, and Window Air Conditioner Service. Teacher Edition.

    Science.gov (United States)

    Clemons, Mark

    This curriculum guide contains six units of instruction for a course in domestic refrigerator, freezer, and window air conditioner service. The units cover the following topics: (1) service fundamentals; (2) mechanical components and functions; (3) electrical components and control devices; (4) refrigerator and freezer service; (5) domestic ice…

  6. Evaluation of ERINA Plus as a coat conditioner in canines

    Directory of Open Access Journals (Sweden)

    Srivastava

    Full Text Available Coat conditioning, deodorant and cleansing properties of ERINA Plus were evaluated in fifty-one dogs of different breeds. More than 80% of dogs showed good to excellent conditioning, deodorant and cleansing effects supported ERINA Plus as safe conditioner shampoo. [Vet. World 2008; 1(12.000: 361-362

  7. Transforming PC Power Supplies into Smart Car Battery Conditioners

    Science.gov (United States)

    Rodriguez-Ascariz, J. M.; Boquete-Vazquez, L.

    2011-01-01

    This paper describes a laboratory project consisting of a PC power supply modification into an intelligent car-battery conditioner with both wireless and wired networking capabilities. Adding a microcontroller to an average PC power supply transforms it into a flexible, intelligent device that can be configured and that is suitable to keep car…

  8. Design of direct solar PV driven air conditioner

    KAUST Repository

    Huang, Bin-Juine

    2015-12-05

    © 2015 Elsevier Ltd. Solar air conditioning system directly driven by stand-alone solar PV is studied. The air conditioning system will suffer from loss of power if the solar PV power generation is not high enough. It requires a proper system design to match the power consumption of air conditioning system with a proper PV size. Six solar air conditioners with different sizes of PV panel and air conditioners were built and tested outdoors to experimentally investigate the running probabilities of air conditioning at various solar irradiations. It is shown that the instantaneous operation probability (OPB) and the runtime fraction (RF) of the air conditioner are mainly affected by the design parameter rpL (ratio of maximum PV power to load power). The measured OPB is found to be greater than 0.98 at instantaneous solar irradiation IT > 600 W m-2 if rpL > 1.71 RF approaches 1.0 (the air conditioner is run in 100% with solar power) at daily-total solar radiation higher than 13 MJ m-2 day-1, if rpL > 3.

  9. Antifungal Effect of a Dental Tissue Conditioner Containing Nystatin-Loaded Alginate Microparticles.

    Science.gov (United States)

    Kim, Hyun-Jin; Son, Jun Sik; Kwon, Tae-Yub

    2018-02-01

    In this in vitro study, nystatin-alginate microparticles were successfully fabricated to control the release of nystatin from a commercial dental tissue conditioner. These nystatin-alginate microparticles were spherical and had a slightly rough surface. The microparticles incorporated into the tissue conditioner were distributed homogeneously throughout the tissue conditioner matrix. The incorporation of the microparticles did not deteriorate the mechanical properties of the original material. The agar diffusion test results showed that the tissue conditioner containing the microparticles had a good antifungal effect against Candida albicans. The nystatin-alginate microparticles efficiently controlled the release of nystatin from the tissue conditioner matrix over the experimental period of 14 days. Moreover, the nystatin-alginate microparticles incorporated in the tissue conditioner showed effective antifungal function even at lower concentrations of nystatin. The current study suggests that the tissue conditioner containing the nystatin-alginate microparticle carrier system has potential as an effective antifungal material.

  10. Residential air-conditioner usage in China and efficiency standardization

    International Nuclear Information System (INIS)

    Wu, Jianghong; Liu, Chaopeng; Li, Hongqi; Ouyang, Dong; Cheng, Jianhong; Wang, Yuanxia; You, Shaofang

    2017-01-01

    Determining the real energy consumption and usage pattern of a room air-conditioner (RAC) are important issues from the point of view of both RAC design and evaluation of its energy efficiency. An air-conditioner's running time is fundamental data for the calculation of SEER and APF values. Therefore, in 2010, a nationwide investigation of RAC usage was conducted and 400 selected air-conditioning-units were monitored for a full year to obtain data on their cooling and heating usage. Two running time curves (cooling and heating) were obtained for the air-conditioners as a function of outdoor air temperatures using statistical analysis. The results show that the 27–30 °C temperature range accounts for more than 52% of the cooling time. Conversely, the 0–8 °C temperature range is associated with more than 75% of the heating time. The research presented in this paper has significantly contributed to China's new variable-speed RAC efficiency standard (GB21455-2013). It also has far-reaching implications for both the air-conditioner industry and energy policy in China due to its different method of calculating energy efficiency. - Highlights: • A nationwide survey to realize China's residential air-conditions usage behaviors. • Air-conditioner running time-environment temperature curves are obtained. • The peak heating demand and peak cooling demand happen at 28 °C and 4 °C, respectively. • The temperature of 27 °C–30 °C accounts for over 52% refrigeration time. • The temperature of 0 °C–8 °C occupies more than 75% heating time.

  11. First phase of small diameter heater experiments in tuff

    International Nuclear Information System (INIS)

    Zimmerman, R.M.

    1983-01-01

    As part of the Nevada Nuclear Waste Storage Investigations (NNWSI) project, we have undertaken small diameter heater experiments in the G-Tunnel Underground Facility on the Nevada Test Site (NTS). These experiments are to evaluate the thermal and hydrothermal behavior which might be encountered if heat producing nuclear waste were disposed of in welded and nonwelded tuffs. The two Phase I experiments discussed have focused on vertical borehole emplacements. In each experiment, temperatures were measured along the surface of the 10.2-cm-dia heater and the 12.7-cm-dia boreholes. For each experiment, measurements were compared with computer model representations. Maximum temperatures reached were: 196 0 C for the welded tuff after 21 days of operations at 800W and 173 0 C for the nonwelded tuff after 35 days of operations at 500W. Computed results indicate that the same heat transfer model (includes conduction and radiation only) can describe the behavior of both tuffs using empirical techniques to describe pore water vaporization. Hydrothermal measurements revealed heat-indiced water migration. Results indicated that small amounts of liquid water migrated into the welded tuff borehole early in the heating period. Once the rock-wall temperatures exceeded 94 0 C, in both tuffs, there was mass transport of water vapor as evidence indicated condensation cooler regions. Borehole pressures remained essentially ambient during the thermal periods

  12. A silicon nanowire heater and thermometer

    Science.gov (United States)

    Zhao, Xingyan; Dan, Yaping

    2017-07-01

    In the thermal conductivity measurements of thermoelectric materials, heaters and thermometers made of the same semiconducting materials under test, forming a homogeneous system, will significantly simplify fabrication and integration. In this work, we demonstrate a high-performance heater and thermometer made of single silicon nanowires (SiNWs). The SiNWs are patterned out of a silicon-on-insulator wafer by CMOS-compatible fabrication processes. The electronic properties of the nanowires are characterized by four-probe and low temperature Hall effect measurements. The I-V curves of the nanowires are linear at small voltage bias. The temperature dependence of the nanowire resistance allows the nanowire to be used as a highly sensitive thermometer. At high voltage bias, the I-V curves of the nanowire become nonlinear due to the effect of Joule heating. The temperature of the nanowire heater can be accurately monitored by the nanowire itself as a thermometer.

  13. Hydrodynamic aspects of the design of feed heaters and de-aerator storage tanks

    International Nuclear Information System (INIS)

    Kubie, J.; Rowe, M.; Jones, E.W.

    1979-01-01

    Regenerative feed heaters of the direct-contact type and feed water deaerators transmit large quantities of saturated, i.e. boiling, water. Drainage of saturated flows has long been a problem because of the possibility of the flow flashing to steam. Adequate drainage of direct-contact heaters is particularly important because of the danger of condensate returning to the turbine and causing serious damage. Likewise, a deaerator must drain easily or the boiler feed pump to which it drains will lose suction head and cavitate. This paper examines a number of hydrodynamic aspects of heater design and operating experience with particular emphasis on the problem of drainage. Formulae are derived and presented with recommendations for their use by designers in the power plant industry. (author)

  14. 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.

  15. High-temperature MEMS Heater Platforms: Long-term Performance of Metal and Semiconductor Heater Materials

    Directory of Open Access Journals (Sweden)

    Theodor Doll

    2006-04-01

    Full Text Available Micromachined thermal heater platforms offer low electrical power consumptionand high modulation speed, i.e. properties which are advantageous for realizing non-dispersive infrared (NDIR gas- and liquid monitoring systems. In this paper, we report oninvestigations on silicon-on-insulator (SOI based infrared (IR emitter devices heated byemploying different kinds of metallic and semiconductor heater materials. Our resultsclearly reveal the superior high-temperature performance of semiconductor over metallicheater materials. Long-term stable emitter operation in the vicinity of 1300 K could beattained using heavily antimony-doped tin dioxide (SnO2:Sb heater elements.

  16. [Verification of bacteriological safety of PCM 40 air conditioner].

    Science.gov (United States)

    Dumas, J L; Ducel, G; Rouge, J C

    1991-01-01

    This study assessed the bacteriological safety of the bedside air conditioner PCM 40 (Howorth Airtech), used for prevention of intraoperative hypothermia, by blowing filtered warm air through a special mattress. The 3 microns bacterial filter of the device released 2,968 +/- 5,618 particles of diameter less than 3 microns per m3 of room air, containing 78,798 +/- 37,243 of such particles per m3. The amount of bacteries in the air pulsed from the mattress was 30 +/- 41 cfu/m3 vs 120 cfu/m3 in the ambient air and in the hot air supply tubing it reached 6 +/- 5 cfu/m3 vs 175 +/- 77 cfu/m3. It is concluded that bacteriological data do not contra-indicate the use of this air conditioner in the operating theater. The only limitations for use are the position (prone or lateral position) and type of surgery (neurosurgery).

  17. Effect of conditioner load on the polishing pad surface during chemical mechanical planarization process

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Cheol Min; Qin, Hong Yi; Hong, Seok Jun; Jeon, Sang Hyuk; Kulkarni, Atul; Kim, Tae Sun [Sungkyunkwan University, Suwon (Korea, Republic of)

    2016-12-15

    During the Chemical mechanical planarization (CMP), the pad conditioning process can affect the pad surface characteristics. Among many CMP process parameters, the improper applied load on the conditioner arm may have adverse effects on the polyurethane pad. In this work, we evaluated the pad surface properties under the various conditioner arm applied during pad conditioning process. The conditioning pads were evaluated for surface topography, surface roughness parameters such as Rt and Rvk and Material removal rate (MRR) and within-wafer non-uniformity after wafer polishing. We observed that, the pad asperities were collapsed in the direction of conditioner rotation and blocks the pad pores applied conditioner load. The Rvk value and MRR were founded to be in relation with 4 > 1 > 7 kgF conditioner load. Hence, this study shows that, 4 kgF applied load by conditioner is most suitable for the pad conditioning during CMP.

  18. Viewpoint Mitigation of emissions through energy efficiency standards for room air conditioners in Malaysia

    International Nuclear Information System (INIS)

    Mahlia, T.M.I.; Masjuki, H.H.; Saidur, R.; Amalina, M.A.

    2004-01-01

    Malaysian economy has grown rapidly in the last two decades. This growth has increased the ownership of household electrical appliances including room air conditioners. The number of users of air conditioners is predicted to grow dramatically in Malaysian households in the future. To reduce energy consumption in the residential sector, the Malaysia Energy Commission is considering implementing minimum energy efficiency standards for room air conditioners in early 2004. This paper attempts to predict the potential mitigation of emissions through energy efficiency standards for room air conditioners in Malaysia. The calculations were based on the growth of room air conditioners ownership data in Malaysian households. The study found that the energy efficiency standards for room air conditioners would mitigate a significant amount of emissions in this country

  19. Active Participation of Air Conditioners in Power System Frequency Control Considering Users’ Thermal Comfort

    Directory of Open Access Journals (Sweden)

    Rongxiang Zhang

    2015-09-01

    Full Text Available Air conditioners have great potential to participate in power system frequency control. This paper proposes a control strategy to facilitate the active participation of air conditioners. For each air conditioner, a decentralized control law is designed to adjust its temperature set point in response to the system frequency deviation. The decentralized control law accounts for the user’s thermal comfort that is evaluated by a fuzzy algorithm. The aggregation of air conditioners’ response is conducted by using the Monte Carlo simulation method. A structure preserving model is applied to the multi-bus power system, in which air conditioners are aggregated at certain load buses. An inner-outer iteration scheme is adopted to solve power system dynamics. An experiment is conducted on a test air conditioner to examine the performance of the proposed decentralized control law. Simulation results on a test power system verify the effectiveness of the proposed strategy for air conditioners participating in frequency control.

  20. Research on a Micro-Grid Frequency Modulation Strategy Based on Optimal Utilization of Air Conditioners

    Directory of Open Access Journals (Sweden)

    Qingzhu Wan

    2016-12-01

    Full Text Available With the proportion of air conditioners increasing gradually, they can provide a certain amount of frequency-controlled reserves for a micro-grid. Optimizing utilization of air conditioners and considering load response characteristics and customer comfort, the frequency adjustment model is a quadratic function model between the trigger temperature of the air conditioner compressor, and frequency variation is provided, which can be used to regulate the trigger temperature of the air conditioner when the micro-grid frequency rises and falls. This frequency adjustment model combines a primary frequency modulation method and a secondary frequency modulation method of the energy storage system, in order to optimize the frequency of a micro-grid. The simulation results show that the frequency modulation strategy for air conditioners can effectively improve the frequency modulation ability of air conditioners and frequency modulation effects of a micro-grid in coordination with an energy storage system.

  1. Development of a solar-powered residential air conditioner

    Science.gov (United States)

    1975-01-01

    The initial objective of the program was the optimization (in terms of cost and performance) of a Rankine cycle mechanical refrigeration system which utilizes thermal energy from a flat solar collector for air conditioning residential buildings. However, feasibility investigations of the adsorption process revealed that a dessicant-type air conditioner offers many significant advantages. As a result, limited efforts were expended toward the optimization of such a system.

  2. Room air conditioner load control under summer comfort constraint

    OpenAIRE

    Da Silva , David; Brancaccio , M; Duplessis , Bruno; Adnot , J

    2010-01-01

    International audience; Load control options interest is growing because it can represent a response to future network investments and to congestion problems. In this frame, the present paper gives a methodology to quantify the value of load control for heat pumps (room air conditioners), in small tertiary and residential buildings, considering the occupant's comfort and the electrical grid needs for load shift. This methodology was applied to a small office building where simulations were ma...

  3. Development and Analysis of Desiccant Enhanced Evaporative Air Conditioner Prototype

    Energy Technology Data Exchange (ETDEWEB)

    Kozubal, E.; Woods, J.; Judkoff, R.

    2012-04-01

    This report documents the design of a desiccant enhanced evaporative air conditioner (DEVAP AC) prototype and the testing to prove its performance. Previous numerical modeling and building energy simulations indicate a DEVAP AC can save significant energy compared to a conventional vapor compression AC (Kozubal et al. 2011). The purposes of this research were to build DEVAP prototypes, test them to validate the numerical model, and identify potential commercialization barriers.

  4. Process and device for replacing heater in PWR pressurizer

    International Nuclear Information System (INIS)

    Gente, D.; Giron, M.

    1990-01-01

    To assure the tight fixation of replacing heater on a pressurizer penetration sleeve, a gas metal-arc welding single pass is executed. A tubular shaft is fixed over end of heater projecting from penetration sleeve. Over shaft is fixed tubular support for the torch which can rotate about axis of support axis heater. Welding torch and welding wire feeder roll are rotated in synchronisation by appropriate motors. Weld is made in single pass round periphery of heater and penetration sleeve [fr

  5. Inverted Unified Power Quality Conditioner to compensate overvoltage

    Directory of Open Access Journals (Sweden)

    Yeison Alberto Garcés Gómez

    2017-07-01

    Full Text Available Introduction: The use of unified power quality conditioners UPQC in the electric systems can correct waveform distortions in a steady state, like harmonics, flicker, and the power factor. Objective: This paper presents a novel approach for active compensation of overvoltage with a UPQC in dual topology or iUPQC. Methodology: The study it is presented in five stages, the section I shows an introduction and the state of the art, section II presents the unified power quality conditioner UPQC, section III describes the generalized reactive power theory applied to the iUPQC (dual topology, section IV shows the numerical simulations and the results and section V presents the conclusions of the study. Results: The results for the application of the iUPQC to the compensation of overvoltage are proved and compared with the more representative theory related to compensation of harmonics and low power factor. Conclusions: The control algorithm presented for the unified power quality conditioner in dual topology allows to compensate the overvoltage in three-phase systems as well as voltage and current harmonics and the low power factor.

  6. 49 CFR 393.77 - Heaters.

    Science.gov (United States)

    2010-10-01

    ... or of any exposed portions of the heaters, inclusive of exhaust stacks, pipes, or conduits shall be... disassembly of any of its parts, including exhaust stacks, pipes, or conduits, upon overturn of the vehicle in... will never exceed 0.2 percent in the cargo space. The exhaust pipe, stack, or conduit if required shall...

  7. Development of multiplexing network for air conditioner systems; Eakon yo LAN system no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, T; Nakazawa, Y; Nakase, M; Sato, Y [Nissan Motor Co. Ltd., Tokyo (Japan); Nomura, M; Okasato, Y; Sunaga, H [Calsonic Corp., Tokyo (Japan)

    1997-10-01

    Plural air flap actuators of the air conditioner system in a vehicle have been integrated into a single-type actuator using two newly developed technologies: super-low-cost multiplexing network technology and digital motor control technology with a 1-bit A/D converter. The number of harnesses and connectors and the handling load of the air conditioner control microcomputer are reduced, so that we succeeded in sharply reducing the cost of the air conditioner system. 9 figs., 2 tabs.

  8. 49 CFR 179.12 - Interior heater systems.

    Science.gov (United States)

    2010-10-01

    ... Design Requirements § 179.12 Interior heater systems. (a) Interior heater systems shall be of approved design and materials. If a tank is divided into compartments, a separate system shall be provided for... 49 Transportation 2 2010-10-01 2010-10-01 false Interior heater systems. 179.12 Section 179.12...

  9. The use of heteroduplex analysis of polymerase chain reaction products to support the possible transmission of Legionella pneumophila from a malfunctioning automobile air conditioner.

    Science.gov (United States)

    Pinar, Ahmet; Ramirez, Julio A; Schindler, Laura L; Miller, Richard D; Summersgill, James T

    2002-03-01

    Air conditioner condensates have not been previously associated with cases of Legionnaires' disease. We report the possible transmission of Legionella pneumophila serogroup 1 from a malfunctioning automobile air conditioning system's leaking water onto the floorboard of a car driven for a long distance by the patient. Heteroduplex analysis of polymerase chain reaction products was used to help establish an epidemiologic link between the water specimen and the patient.

  10. Hydrothermal field test with french candidate clay embedding steel heater in the Stripa mine

    International Nuclear Information System (INIS)

    Pusch, R.; Karnland, O.; Lajudie, A.; Lechelle, J.; Bouchet, A.

    1992-12-01

    Field experiments with French kaolinite/smectite clay heated up to 170 degrees C in boreholes in granite were conducted for 8 months and 4 years. The clay heated for 8 months has a considerably higher water content and it had undergone much less changes in mineralogy and physical properties than the clay exposed to heating for 4 years. The drying of the latter clay was probably caused by hydrogen gas from corrosion of the heater. The clay next to the heater turned into clay-stone despite conversion of the kaolinite component to smectite. (42 refs)

  11. Fire-tube immersion heater optimization program and field heater audit program

    Energy Technology Data Exchange (ETDEWEB)

    Croteau, P. [Petro-Canada, Calgary, AB (Canada)

    2007-07-01

    This presentation provided an overview of the top 5 priorities for emission reduction and eco-efficiency by the Petroleum Technology Alliance of Canada (PTAC). These included venting of methane emissions; fuel consumption in reciprocating engines; fuel consumption in fired heaters; flaring and incineration; and fugitive emissions. It described the common concern for many upstream operating companies as being energy consumption associated with immersion heaters. PTAC fire-tube heater and line heater studies were presented. Combustion efficiency was discussed in terms of excess air, fire-tube selection, heat flux rate, and reliability guidelines. Other topics included heat transfer and fire-tube design; burner selection; burner duty cycle; heater tune up inspection procedure; and insulation. Two other programs were also discussed, notably a Petro-Canada fire-tube immersion heater optimization program and the field audit program run by Natural Resources Canada. It was concluded that improved efficiency involves training; managing excess air in combustion; managing the burner duty cycle; striving for 82 per cent combustion efficiency; and providing adequate insulation to reduce energy demand. tabs., figs.

  12. Fuzzy Logic Approach to Diagnosis of Feedwater Heater Performance Degradation

    International Nuclear Information System (INIS)

    Kang, Yeon Kwan; Kim, Hyeon Min; Heo, Gyun Young; Sang, Seok Yoon

    2014-01-01

    failure mode of feedwater heater such as high drain level, low shell-side pressure, tube-side plugging and water box plate defect based on fuzzy logic approach and simulation model

  13. Fuzzy Logic Approach to Diagnosis of Feedwater Heater Performance Degradation

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Yeon Kwan; Kim, Hyeon Min; Heo, Gyun Young [Kyung Hee University, Yongin (Korea, Republic of); Sang, Seok Yoon [Engineering and Technical Center, Korea Hydro, Daejeon (Korea, Republic of)

    2014-08-15

    failure mode of feedwater heater such as high drain level, low shell-side pressure, tube-side plugging and water box plate defect based on fuzzy logic approach and simulation model.

  14. Cell module and fuel conditioner development

    Science.gov (United States)

    Hoover, D. Q., Jr.

    1980-01-01

    Components for the first 5 cell stack (no cooling plates) of the MK-2 design were fabricated. Preliminary specfications and designs for the components of a 23 cell MK-1 stack with four DIGAS cooling plates were developed. The MK-2 was selected as a bench mark design and a preliminary design of the facilities required for high rate manufacture of fuel cell modules was developed. Two stands for testing 5 cell stacks were built and design work for modifying existing stands and building new stands for 23 and 80 cell stacks was initiated. Design and procurement of components and materials for the catalyst test stand were completed and construction initiated. Work on the specifications of pipeline gas, tap water and recovered water and definition of equipment required for treatment was initiated. An innovative geometry for the reformer was conceived and modifications of the computer program to be used in its design were stated.

  15. Low-Temperature Baseboard Heaters in Built Environments

    Energy Technology Data Exchange (ETDEWEB)

    Ploskic, Adnan

    2010-10-15

    The European Union has adopted a plan to decrease 20 % of total energy consumption through improved energy efficiency by 2020. One way of achieving this challenging goal may be to use efficient water-based heating systems supplied by heat pumps or other sustainable systems. The goal of this research was to analyze and improve the thermal performance of water-based baseboard heaters at low-temperature water supply. Both numerical (CFD) and analytical simulations were used to investigate the heat efficiency of the system. An additional objective of this work was to ensure that the indoor thermal comfort was satisfied in spaces served by such a low-temperature heating system. Analyses showed that it was fully possible to cover both transmission and ventilation heat losses using baseboard heaters supplied by 45 deg C water flow. The conventional baseboards, however, showed problems in suppressing the cold air down-flow created by 2.0 m high glazing and an outdoor temperature of -12 deg C. The draught discomfort at ankle level was slightly above the upper limit recommended by international and national standards. On the other hand, thermal baseboards with integrated ventilation air supply showed better ability to neutralize cold downdraught at the same height and conditions. Calculations also showed that the heat output from the integrated system with one ventilation inlet was approximately twice as high as that of the conventional one. The general conclusion from this work was that low temperature baseboards, especially with integrated ventilation air supply, are an efficient heating system and able to be combined with devices that utilize the low-quality sustainable energy sources such as heat pumps

  16. Evaluation of environmental and physiological factors of a whole ceiling-type air conditioner using a salivary biomarker

    Energy Technology Data Exchange (ETDEWEB)

    Tahara, Yusuke; Yamaguchi, Masaki [Graduate School of Engineering, Iwate University, 4-3-5 Ueda, Morioka 020-8551 (Japan); Morito, Naomi; Nishimiya, Hajime; Yamagishi, Hideyuki [Asahi Kasei Homes Corporation, R and D Laboratories, 2-1 Samejima, Fuji, Shizuoka 416-8501 (Japan)

    2009-06-15

    In order to improve environmental condition such as humidity and airflow in living spaces, a whole ceiling-type air conditioner is proposed. This novel air conditioner exhaust dispersed airflow from the whole ceiling by using a 3-dimensional knit fabric. The purpose of this paper is to reveal the effects when controlling humidity and airflow using the whole ceiling-type air conditioner compared to a commercialized concentrated exhaust air conditioner (normal-type air conditioner) under the same temperature. Salivary {alpha}-amylase activity (SAA) was used as an index of sympathetic nervous activity. An acute experiment for a 15 min period was conducted using 12 healthy young female adults. No significant differences in room and skin temperatures were observed between the whole ceiling-type air conditioner and the normal-type air conditioner. The whole ceiling-type air conditioner showed 11.1% lower humidity than the normal-type air conditioner. The whole ceiling-type air conditioner showed one-thirteenth the airflow of the normal-type air conditioner. As a result, the PMV of the whole ceiling-type air conditioner was more comfortable level than the normal one. Moreover, subjective evaluation questionnaire revealed a significant difference was observed in wind perception (windy). The SAA of subjects under the whole ceiling-type air conditioner showed significantly low values compared with the normal-type air conditioner. It was found that the subject's sympathetic nervous activity has been inactivated under the conditions of the whole ceiling-type air conditioner. Thus, it was revealed that the whole ceiling-type air conditioner provides a more comfortable air environment by reducing physical stimulations to humans. (author)

  17. Lid heater for glass melter

    International Nuclear Information System (INIS)

    Phillips, T.D.

    1993-01-01

    A glass melter having a lid electrode for heating the glass melt radiantly. The electrode comprises a series of INCONEL 690 tubes running above the melt across the melter interior and through the melter walls and having nickel cores inside the tubes beginning where the tubes leave the melter interior and nickel connectors to connect the tubes electrically in series. An applied voltage causes the tubes to generate heat of electrical resistance for melting frit injected onto the melt. The cores limit heat generated as the current passes through the walls of the melter. Nickel bus connection to the electrical power supply minimizes heat transfer away from the melter that would occur if standard copper or water-cooled copper connections were used between the supply and the INCONEL 690 heating tubes. 3 figures

  18. 16 CFR Appendix I to Part 305 - Heating Performance and Cost for Central Air Conditioners

    Science.gov (United States)

    2010-01-01

    ... RULEâ) Pt. 305, App. I Appendix I to Part 305—Heating Performance and Cost for Central Air Conditioners... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Heating Performance and Cost for Central Air Conditioners I Appendix I to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC...

  19. Bacterial community structures in air conditioners installed in Japanese residential buildings.

    Science.gov (United States)

    Hatayama, Kouta; Oikawa, Yurika; Ito, Hiroyuki

    2018-01-01

    The bacterial community structures in four Japanese split-type air conditioners were analyzed using a next-generation sequencer. A variety of bacteria were detected in the air filter of an air conditioner installed on the first floor. In the evaporator of this air conditioner, bacteria belonging to the genus Methylobacterium, or the family of Sphingomonadaceae, were predominantly detected. On the other hand, the majority of bacteria detected in the air filters and evaporators of air conditioners installed on the fifth and twelfth floors belonged to the family Enterobacteriaceae. The source of bacteria belonging to the family Enterobacteriaceae may have been aerosols generated by toilet flushing in the buildings. Our results suggested the possibility that the bacterial contamination in the air conditioners was affected by the floor level on which they were installed. The air conditioner installed on the lower floor, near the ground, may have been contaminated by a variety of outdoor bacteria, whereas the air conditioners installed on floors more distant from the ground may have been less contaminated by outdoor bacteria. However, these suppositions may apply only to the specific split-type air conditioners that we analyzed, because our sample size was small.

  20. 16 CFR Appendix H to Part 305 - Cooling Performance and Cost for Central Air Conditioners

    Science.gov (United States)

    2010-01-01

    ... RULEâ) Pt. 305, App. H Appendix H to Part 305—Cooling Performance and Cost for Central Air Conditioners... Split System Units Central Air Conditioners (Cooling Only): All capacities 10.9 23.0 Heat Pumps (Cooling... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Cooling Performance and Cost for Central Air...

  1. Ansys Benchmark of the Single Heater Test

    International Nuclear Information System (INIS)

    H.M. Wade; H. Marr; M.J. Anderson

    2006-01-01

    The Single Heater Test (SHT) is the first of three in-situ thermal tests included in the site characterization program for the potential nuclear waste monitored geologic repository at Yucca Mountain. The heating phase of the SHT started in August 1996 and was concluded in May 1997 after 9 months of heating. Cooling continued until January 1998, at which time post-test characterization of the test block commenced. Numerous thermal, hydrological, mechanical, and chemical sensors monitored the coupled processes in the unsaturated fractured rock mass around the heater (CRWMS M and O 1999). The objective of this calculation is to benchmark a numerical simulation of the rock mass thermal behavior against the extensive data set that is available from the thermal test. The scope is limited to three-dimensional (3-D) numerical simulations of the computational domain of the Single Heater Test and surrounding rock mass. This calculation supports the waste package thermal design methodology, and is developed by Waste Package Department (WPD) under Office of Civilian Radioactive Waste Management (OCRWM) procedure AP-3.12Q, Revision 0, ICN 3, BSCN 1, Calculations

  2. Locally produced natural conditioners for dewatering of faecal sludge.

    Science.gov (United States)

    Gold, Moritz; Dayer, Pauline; Faye, Marie Christine Amie Sene; Clair, Guillaume; Seck, Alsane; Niang, Seydou; Morgenroth, Eberhard; Strande, Linda

    2016-11-01

    In urban areas of low-income countries, treatment of faecal sludge (FS) is insufficient or non-existent. This results in large amounts of FS being dumped into the environment. Existing treatment technologies for FS, such as settling-thickening tanks and drying beds, are land intensive which is limiting in urban areas. Enhanced settling and dewatering by conditioning was evaluated in order to reduce the treatment footprint (or increase treatment capacity). Conventional wastewater conditioners, such as commercially available lime and polymers, are expensive, and commonly rely on complex supply chains for use in low-income countries. Therefore, the treatment performance of five conditioners which could be produced locally was evaluated: Moringa oleifera seeds and press cake, Jatropha curcas seeds, Jatropha Calotropis leaves and chitosan. M. oleifera seeds and press cake, and chitosan improved settling and dewatering and had a similar performance compared to lime and polymers. Optimal dosages were 400-500 kg M. oleifera/t TS, 300-800 kg lime/t TS and 25-50 kg polymer solution/t TS. In comparison, chitosan required 1.5-3.75 kg/t TS. These dosages are comparable to those recommended for wastewater (sludge). The results indicate that conditioning of FS can reduce total suspended solids (TSS) in the effluent of settling-thickening tanks by 22-81% and reduce dewatering time with drying beds by 59-97%. This means that the area of drying beds could be reduced by 59-97% with end-use as soil conditioner, or 9-26% as solid fuel. Least expensive options and availability will depend on the local context. In Dakar, Senegal, chitosan produced from shrimp waste appears to be most promising.

  3. Refrigerant lines in split-type air conditioners

    Energy Technology Data Exchange (ETDEWEB)

    Rettenberger, P

    1979-01-01

    Condensator and evaporating units of split-type air conditioners are evaluated and filled with the refrigerant by the producer. The line systems are hermetically closed and prevent the loss of refrigerant and the penetration of moisture or dirt. The best installation method is the 'bendable lines'. They combine flexibility and easy installation with the advantages of the copper pipe. Several ducting systems and their connecting elements like couplings and valves are described, their installation is explained. These flexible systems are especially suitable for small air-condition plants of the split-type the evaporating unit of which is portable and can put where it is desired.

  4. Capacity modulation of an inverter-driven multi-air conditioner using electronic expansion valves

    International Nuclear Information System (INIS)

    Choi, J.M.; Kim, Y.C.

    2003-01-01

    An inverter-driven multi-air conditioner provides the benefits of comfort, energy conservation and easy maintenance. Recently, the multi-air conditioner has been employed in small and medium-sized buildings. However, the performance data and control algorithm for multi-air conditioners are limited in literature due to complicated system parameters and operating conditions. In the present study, the performance of an inverter-driven multi-air conditioner having two indoor units with electronic expansion valves (EEV) was measured by varying indoor loads, EEV opening, and compressor speed. Based on the experimental results, the operating characteristics and capacity modulation of the inverter-driven multi-air conditioner are discussed. As a result, it is suggested that the superheats for both indoor units have to be maintained around 4 o C by utilizing the EEVs in this system, and consequently, the compressor speed needs to be adjusted to provide optimum cooling capacity for each indoor unit

  5. Heater Validation for the NEXT-C Hollow Cathodes

    Science.gov (United States)

    Verhey, Timothy R.; Soulas, George C.; Mackey, Jonathan A.

    2018-01-01

    Swaged cathode heaters whose design was successfully demonstrated under a prior flight project are to be provided by the NASA Glenn Research Center for the NEXT-C ion thruster being fabricated by Aerojet Rocketdyne. Extensive requalification activities were performed to validate process controls that had to be re-established or revised because systemic changes prevented reuse of the past approaches. A development batch of heaters was successfully fabricated based on the new process controls. Acceptance and cyclic life testing of multiple discharge and neutralizer sized heaters extracted from the development batch was initiated in August, 2016, with the last heater completing testing in April, 2017. Cyclic life testing results substantially exceeded the NEXT-C thruster requirement as well as all past experience for GRC-fabricated units. The heaters demonstrated ultimate cyclic life capability of 19050 to 33500 cycles. A qualification batch of heaters is now being fabricated using the finalized process controls. A set of six heaters will be acceptance and cyclic tested to verify conformance to the behavior observed with the development heaters. The heaters for flight use will be then be provided to the contractor from the remainder of the qualification batch. This paper summarizes the fabrication process control activities and the acceptance and life testing of the development heater units.

  6. Tube Plugging Criteria for the High-pressure Heaters of Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyungnam; Cho, Nam-Cheoul; Lee, Kuk-hee [KHNP Central Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    In this paper, a method to establish the tube plugging criteria of BOP heat exchangers is introduced and the tube plugging criteria for the high pressure heaters of a nuclear power plant. This method relies on the similar plugging criteria used in the steam generator tubes. Power generation field urges nuclear power plants to reduce operating and maintaining costs to remain competitive. To reduce the cost by means of preventing the lowering thermal efficiency, the inspection of balance-of-plant heat exchanger, which was treated as not important work, becomes important. The tubing materials and tube thickness of heat exchangers in nuclear power plants are selected to withstand system temperature, pressure, and corrosion. But tubes have experienced leaks and failures and plugged based upon eddy current testing (ET) results. There are some problems for plugging the heat exchanger tubes since the criterion and its basis are not clearly described. For this reason, the criteria for the tube wall thickness are addressed in order to operate the heat exchangers in nuclear power plant without trouble during the cycle. The feed water heater is a kind of heat exchanger which raises the temperature of water supplied from the condenser. The heat source of high-pressure heaters is the extraction steam from the high-pressure turbine and moisture separator re-heater. If the tube wall of the heater is broken, the feed water flowing inside the tube intrudes to shell side. This forces the turbine to be stop in order to protect it. There are many codes and standards to be referred for calculating the minimum thickness of the heat exchanger tube in the designing stage. However, the codes and standards related to show the tube plugging criteria may not exist currently. A method to establish the tube plugging criteria of BOP heat exchangers is introduced and the tube plugging criteria for the high pressure heaters of Ulchin NPP No. 3 and 4. This method relies on the similar plugging

  7. Large-scale in situ heater tests for hydrothermal characterization at Yucca Mountain

    International Nuclear Information System (INIS)

    Buscheck, T.A.; Wilder, D.G.; Nitao, J.J.

    1993-01-01

    To safely and permanently store high-level nuclear waste, the potential Yucca Mountain repository site must mitigate the release and transport of radionuclides for tens of thousands of years. In the failure scenario of greatest concern, water would contact a waste package, accelerate its failure rate, and eventually transport radionuclides to the water table. Our analyses indicate that the ambient hydrological system will be dominated by repository-heat-driven hydrothermal flow for tens of thousands of years. In situ heater tests are required to provide an understanding of coupled geomechanical-hydrothermal-geochemical behavior in the engineered and natural barriers under repository thermal loading conditions. In situ heater tests have been included in the Site Characterization Plan in response to regulatory requirements for site characterization and to support the validation of process models required to assess the total systems performance at the site. Because of limited time, some of the in situ tests will have to be accelerated relative to actual thermal loading conditions. We examine the trade-offs between the limited test duration and generating hydrothermal conditions applicable to repository performance during the entire thermal loading cycle, including heating (boiling and dry-out) and cooldown (re-wetting). For in situ heater tests to be applicable to actual repository conditions, a minimum heater test duration of 6-7 yr (including 4 yr of full-power heating) is required

  8. Design and stability limits of the HPLWR re-heater

    International Nuclear Information System (INIS)

    Herbell, H.; Class, A.; Starflinger, J.; Schulenberg, T.

    2010-01-01

    The High Performance Light Water Reactor (HPLWR) is a particular design study of a supercritical water cooled reactor. A heat exchanger design has been proposed for the re-heater as a shell-and-tube heat exchanger. Inside the tubes fluid undergoes pseudo-condensing, e.g. it changes its density from steam-like to liquid-like properties (from 80 kg/m 3 to 582 kg/m 3 ) at supercritical pressure, whereas the shell side superheats intermediate pressure steam. For sub-critical pressures an instability has been reported by Goodykoontz and Dorsch (19679. The experiment exhibits unstable steam condensation in case of downward flow inside a tube of 7.4 mm diameter and 2.42 m length in some specific cases. The counter-current condenser was cooled with water flowing in an annulus surrounding the condenser tube. This experiment motivates the current investigation of instabilities for supercritical pseudo-condensation. The study includes static instabilities, i.e. Ledingegg instability and flow maldistribution of the parallel tubes, as well as pressure drop oscillations. At the present stage, no instabilities are predicted for the specific operation conditions of the HPLWR. The commercial system code APROS is used to perform one dimensional transient simulations of the described experiment to understand the physical mechanism. These simulations show that choking flow initiates the pressure oscillations. These periodically change steam temperatures, and consequently the condensation rate. In turn, this modifies the sound speed which is responsible for choking. Condensate reverse flow at choked conditions triggers the pressure waves. APROS simulations and experimental results agree well both in pressure amplitude and frequency. APROS simulations at supercritical pressure conditions did not exhibit any instability as the fluid velocity is clearly sub-sonic in the entire HPLWR re-heater. (authors)

  9. Characterization of ryanodine receptor and Ca2+-ATPase isoforms in the thermogenic heater organ of blue marlin (Makaira nigricans).

    Science.gov (United States)

    Morrissette, Jeffery M; Franck, Jens P G; Block, Barbara A

    2003-03-01

    A thermogenic organ is found beneath the brain of billfishes (Istiophoridae), swordfish (Xiphiidae) and the butterfly mackerel (Scombridae). The heater organ has been shown to warm the brain and eyes up to 14 degrees C above ambient water temperature. Heater cells are derived from extraocular muscle fibers and express a modified muscle phenotype with an extensive transverse-tubule (T-tubule) network and sarcoplasmic reticulum (SR) enriched in Ca(2+)-ATPase (SERCA) pumps and ryanodine receptors (RyRs). Heater cells have a high mitochondria content but have lost most of the contractile myofilaments. Thermogenesis has been hypothesized to be associated with release and reuptake of Ca(2+). In this study, Ca(2+) fluxes in heater SR vesicles derived from blue marlin (Makaira nigricans) were measured using fura-2 fluorescence. Upon the addition of MgATP, heater SR vesicles rapidly sequestered Ca(2+). Uptake of Ca(2+) was thapsigargin sensitive, and maximum loading ranged between 0.8 micro mol Ca(2+) mg(-1) protein and 1.0 micro mol Ca(2+) mg(-1) protein. Upon the addition of 10 mmol l(-1) caffeine or 350 micro mol l(-1) ryanodine, heater SR vesicles released only a small fraction of the loaded Ca(2+). However, ryanodine could elicit a much larger Ca(2+) release event when the activity of the SERCA pumps was reduced. RNase protection assays revealed that heater tissue expresses an RyR isoform that is also expressed in fish slow-twitch skeletal muscle but is distinct from the RyR expressed in fish fast-twitch skeletal muscle. The heater and slow-twitch muscle RyR isoform has unique physiological properties. In the presence of adenine nucleotides, this RyR remains open even though cytoplasmic Ca(2+) is elevated, a condition that normally closes RyRs. The fast Ca(2+) sequestration by the heater SR, coupled with a physiologically unique RyR, is hypothesized to promote Ca(2+) cycling, ATP turnover and heat generation. A branch of the oculomotor nerve innervates heater organs

  10. Huffing air conditioner fluid: a cool way to die?

    Science.gov (United States)

    Phatak, Darshan R; Walterscheid, Jeffrey

    2012-03-01

    "Huffing," the form of substance abuse involving inhalants, is growing in popularity because of the ease and availability of chemical inhalants in many household products. The purpose in huffing is to achieve euphoria when the chemicals in question interact with the central nervous system in combination with oxygen displacement. The abuser is lulled into a false sense of safety despite the well-documented potential for lethal cardiac arrhythmia and the effects of chronic inhalant abuse, including multisystem organ failure, and brain damage. Huffing air conditioner fluid is a growing problem given the accessibility to outdoor units and their fluid components, such as difluorochloromethane(chlorodifluoromethane, Freon), and we have classified multiple cases of accidental death due to the toxicity of difluorochloromethane. Given the ubiquity of these devices and the vast lack of gating or security devices, they make an inviting target for inhalant abusers. Acute huffing fatalities have distinct findings that are present at the scene, given the position of the decedent and proximity to the air conditioner unit. The purpose of the autopsy in these cases is to exclude other potential causes of death and to procure specimens for toxicological analysis.

  11. Shampoo and Conditioners: What a Dermatologist Should Know?

    Science.gov (United States)

    D'Souza, Paschal; Rathi, Sanjay K

    2015-01-01

    Dermatologists many a times encounter questions from patients and even colleagues asking about how to keep their hair looking clean, healthy and beautiful. Therefore, familiarity and a basic knowledge of the available hair care products will help them to guide their patients properly. A shampoo not only provides the cleaning of the scalp skin and hair as its primary function, but in addition also serves to condition and beautify hair and acts as an adjunct in the management of various scalp disorders. To achieve this, various ingredients in the correct proportion are mixed to provide a shampoo which is suitable for individuals having different hair types and hair need. Among the ingredients that go into the making of a shampoo are detergents, conditioners, thickeners, sequestering agents, pH adjusters, preservatives and specialty additives. Hair conditioners are designed to improve hair manageability, decrease hair static electricity and add luster. They are used in several ways depending upon the state of hair and requirement of the individual. This article attempts to put forward the basic and practical aspects regarding use of these products.

  12. Shampoo and conditioners: What a dermatologist should know?

    Directory of Open Access Journals (Sweden)

    Paschal D′Souza

    2015-01-01

    Full Text Available Dermatologists many a times encounter questions from patients and even colleagues asking about how to keep their hair looking clean, healthy and beautiful. Therefore, familiarity and a basic knowledge of the available hair care products will help them to guide their patients properly. A shampoo not only provides the cleaning of the scalp skin and hair as its primary function, but in addition also serves to condition and beautify hair and acts as an adjunct in the management of various scalp disorders. To achieve this, various ingredients in the correct proportion are mixed to provide a shampoo which is suitable for individuals having different hair types and hair need. Among the ingredients that go into the making of a shampoo are detergents, conditioners, thickeners, sequestering agents, pH adjusters, preservatives and specialty additives. Hair conditioners are designed to improve hair manageability, decrease hair static electricity and add luster. They are used in several ways depending upon the state of hair and requirement of the individual. This article attempts to put forward the basic and practical aspects regarding use of these products.

  13. Towards a Residential Air-Conditioner Usage Model for Australia

    Directory of Open Access Journals (Sweden)

    Mark Goldsworthy

    2017-08-01

    Full Text Available Realistic models of occupant behaviour in relation to air-conditioner (a/c use are fundamentally important for developing accurate building energy simulation tools. In Australia and elsewhere, such simulation tools are inextricably bound both in legislation and in the design of new technology, electricity infrastructure and regulatory schemes. An increasing number of studies in the literature confirm just how important occupants are in determining overall energy consumption, but obtaining the data on which to build behaviour models is a non-trivial task. Here data is presented on air-conditioner usage derived from three different types of case study analyses. These are: (i use of aggregate energy consumption data coupled with weather, demographic and building statistics across Australia to estimate key predictors of energy use at the aggregate level; (ii use of survey data to determine characteristic a/c switch on/off behaviours and usage frequencies; and (iii use of detailed household level sub-circuit monitoring from 140 households to determine a/c switch on/off probabilities and their dependence on different building and occupant parameters. These case studies are used to assess the difficulties associated with translation of different forms of individual, aggregate and survey based information into a/c behaviour simulation models. Finally a method of linking the data gathering methodologies with the model development is suggested. This method would combine whole-of-house “smart”-meter data measurements with linked targeted occupant surveying.

  14. Leak Detection of High Pressure Feedwater Heater Using Empirical Models

    International Nuclear Information System (INIS)

    Lee, Song Kyu; Kim, Eun Kee; Heo, Gyun Young; An, Sang Ha

    2009-01-01

    Even small leak from tube side or pass partition within the high pressure feedwater heater (HPFWH) causes a significant deficiency in its performance. Plant operation under the HPFWH leak condition for long time will result in cost increase. Tube side leak within HPFWH can produce the high velocity jet of water and it can cause neighboring tube failures. However, most of plants are being operated without any information for internal leaks of HPFWH, even though it is prone to be damaged under high temperature and high pressure operating conditions. Leaks from tubes and/or pass partition of HPFWH occurred in many nuclear power plants, for example, Mihama PS-2, Takahama PS-2 and Point Beach Nuclear Plant Unit 1. If the internal leaks of HPFWH are monitored, the cost can be reduced by inexpensive repairs relative to loss in performance and moreover plant shutdown as well as further tube damages can be prevented

  15. Adhesive bonding of resin composite to various titanium surfaces using different metal conditioners and a surface modification system

    Directory of Open Access Journals (Sweden)

    Hercules Jorge ALMILHATTI

    2013-12-01

    Full Text Available Objective: This study evaluated the effect of three metal conditioners on the shear bond strength (SBS of a prosthetic composite material to cpTi grade I having three surface treatments. Material and Methods: One hundred sixty eight rivet-shaped specimens (8.0x2.0 mm were cast and subjected to polishing (P or sandblasting with either 50 mm (50SB or 250 mm (250SB Al2O3. The metal conditioners Metal Photo Primer (MPP, Cesead II Opaque Primer (OP, Targis Link (TL, and one surface modification system Siloc (S, were applied to the specimen surfaces, which were covered with four 1-mm thick layers of resin composite. The resin layers were exposed to curing light for 90 s separately. Seven specimens from each experimental group were stored in water at 37ºC for 24 h while the other 7 specimens were subjected to 5,000 thermal cycles consisting of water baths at 4ºC and 60ºC (n=7. All specimens were subjected to SBS test (0.5 mm/min until failure occurred, and further 28 specimens were analyzed using scanning electron microscope (SEM and X-ray energy-dispersive spectroscopy (EDS. Data were analyzed by 3-way ANOVA followed by post-hoc Tukey's test (α=0.05. Results: On 50SB surfaces, OP groups showed higher SBS means than MPP (P<0.05, while no significant difference was found among OP, S, and TL groups. On 250SB surfaces, OP and TL groups exhibited higher SBS than MPP and S (P<0.05. No significant difference in SBS was found between OP and TL groups nor between MPP and S groups. The use of conditioners on 250SB surfaces resulted in higher SBS means than the use of the same products on 50SB surfaces (P<0.05. Conclusion: Sandblasting associated with the use of metal conditioners improves SBS of resin composites to cpTi.

  16. Multi-step heater deployment in a subsurface formation

    Science.gov (United States)

    Mason, Stanley Leroy [Allen, TX

    2012-04-03

    A method for installing a horizontal or inclined subsurface heater includes placing a heating section of a heater in a horizontal or inclined section of a wellbore with an installation tool. The tool is uncoupled from the heating section. A lead in section is mechanically and electrically coupled to the heating section of the heater. The lead-in section is located in an angled or vertical section of the wellbore.

  17. Feedwater heater tube-to-tubesheet connections

    International Nuclear Information System (INIS)

    Yokell, S.

    1993-01-01

    This paper discusses some practical aspects of expanded, welded, and welded-and-expanded feedwater heater tube-to-tubesheet joints. It outlines elastic-plastic tube expanding theory. It examines uniform-pressure-expanded tube joint strength and correlating roller-expanded joint strength with wall reduction and rolling torque. For materials subject to stress-corrosion cracking (SCC), it recommends heat treating tube ends before expanding. For materials subject to fatigue and tube-end cracking, it advocates two-stage expanding: (1) expanding enough to create firm tube-hole contact over the full tubesheet thickness; and (2) re-expanding at full pressure or torque. The paper emphasizes the desirability of segregating heats of tubing, mapping the tube-heat locations and making the heat map a permanent part of the heater maintenance file. It recommends when to provide TEMA/HEI Power Plant Standard annular grooves for roller-expanding and provides an equation for determining optimum groove width for uniform-pressure expanding. The paper also reviews welding requirements for welds of tubes to tubesheets. The review covers front-face welding before and after expanding and the reasons for welding first. It outlines current thinking about definitions of strength- and seal-welds of front-face welded joint in terms of their functions and load-carrying abilities. It presents a proposal for determining the required size of strength welds for use in Section VIII of the ASME Boiler and Pressure Vessel Code (the Code). It shows why welded-and-expanded feedwater heater tube-to-tubesheet joints should be full-strength and full-depth expanded. It makes recommendations for pressure- and leak-testing. This work also proposes the industry consider butt welding the tubes to the steam-side face of the tubesheet as a regular method of tube joining. The results of a survey of manufacturers practices are appended. 30 refs., 14 figs

  18. Experimental study of a high-efficiency low-emission surface combustor-heater

    International Nuclear Information System (INIS)

    Xiong, Tian-yu; Khinkis, M.J.; Fish, F.F.

    1991-01-01

    The surface combustor-heater is a combined combustion/heat-transfer device in which the heat-exchange surfaces are embedded in a stationary bed of refractory material where gaseous fuel is burned. Because of intensive heat radiation from the hot solid particles and enhanced heat convection from the gas flow to the heat-exchange tubes, heat transfer is significantly intensified. Removing heat simultaneously with the combustion process has the benefit of reducing the combustion temperature, which suppresses NO x formation. A basic experimental study was conducted on a 60-kW bench-scale surface combustor-heater with two rows of water-cooled tube coils to evaluate its performance and explore the mechanism of combined convective-radiative heat transfer and its interaction with combustion in the porous matrix. Combustion stability in the porous matrix, heat-transfer rates, emissions, and pressure drop through the unit have been investigated for the variable parameters of operation and unit configurations. Experimental results have demonstrated that high combustion intensity (up to 2.5 MW/m 2 ), high heat-transfer rates (up to 310 kW/m 2 ), high density of energy conversion (up to 8 MW/m 3 ), as well as ultra-low emissions (NO x and CO as low as 15 vppm*) have been achieved. The excellent performance of the test unit and the extensive data obtained from the present experimental study provide the basis for further development of high-efficiency and ultra low-emission water heaters, boilers, and process heaters based on the surface combustor-heater concept. 4 refs., 16 figs

  19. Need Analysis for Air Conditioners in Public Sector of Surabaya City Government

    Directory of Open Access Journals (Sweden)

    Dwiarti Larasputri

    2017-01-01

    Full Text Available In typical buildings, air conditioners have the biggest percentage in energy consumption among all sectors. It makes a good management for air conditioners is needed and important in order to use the energy efficiently. Having a very hot and humid weather, it gives impact that most of buildings in Surabaya installed air conditioners, including Surabaya City Government office buildings. However, there is no regulation nor guidance how to manage air conditioners in Surabaya City Government, while Surabaya itself has a goal to become a green-eco city. Then, the existing condition of air conditioners usage in Surabaya Government units (SKPDs is evaluated. The evaluation resulted that most of air conditioners were over capacity and not all of them were efficient in energy consumption. Therefore, a need analysis is required to help Surabaya City Government managing its air conditioners better. By applying two different concepts, one is based on the architectural view and another one is based on green building criteria, the existing condition is analyzed and two procedures of need analysis are produced. The procedures can be implemented for two different conditions of office building rooms in Surabaya City Government.

  20. Electrical resistivity monitoring of the single heater test in Yucca Mountain

    International Nuclear Information System (INIS)

    Ramirez, A.

    1997-10-01

    Of the several thermal, mechanical and hydrological measurements being used to monitor the rockmass response in the Single Heater Test, electrical resistance tomography (ERT) is being used to monitor the movement of liquid water with a special interest in the movement of condensate out of the system. Images of resistivity change were calculated using data collected before, during and after the heating episode. This report will concentrate on the results obtained after heating ceased; previous reports discuss the results obtained during the heating phase. The changes recovered show a region of increasing resistivity approximately centered around the heater as the rock mass cooled. The size of this region grows with time and the resistivity increases become stronger. The increases in resistivity are caused by both temperature and saturation changes. The Waxman Smits model has been used to calculate rock saturation after accounting for temperature effects. The saturation estimates suggest that during the heating phase, a region of drying forms around the heater. During the cooling phase, the dry region has remained relatively stable. Wetter rock regions which developed below the heater during the heating phase, are slowly becoming smaller in size during the cooling phase. The last set of images indicate that some rewetting of the dry zone may be occurring. The accuracy of the saturation estimates depends on several factors that are only partly understood

  1. Electrical resistivity monitoring of the thermomechanical heater test in Yucca Mountain

    International Nuclear Information System (INIS)

    Ramirez, A.; Daily, W.; Buettner, M.

    1997-01-01

    A test is being conducted in the densely welded Topopah Springs tuff within Yucca Mountain, Nevada to study the thermomechanical and hydrological behavior of this horizon when it is headed. A single 4 kW heater, placed in a horizontal borehole, was turned on August, 1996 and will continue to heat the rockmass until April 1997. Of the several thermal, mechanical and hydrological measurements being used to monitor the rockmass response, electrical resistance tomography (ERT) is being used to monitor the movement of liquid water with a special interest in the movement of condensate out of the system. Four boreholes, containing a total of 30 ERT electrodes, were drilled to form the sides of a 30 foot square with the heater at the center and perpendicular to the plane. Images of resistivity change were calculated using data collected before and during the heating episode. The changes recovered show a region of decreasing resistivity approximately centered around the heater. The size this region grows with time and the resistivity decreases become stronger. The changes in resistivity are caused by both temperature and saturation changes. The observed resistivity changes suggest that the rock adjacent to the heater dries as heating progresses. This dry region is surrounded by a region of increased saturation where steam recondenses and imbibes into the rock

  2. Electrical resistivity monitoring of the thermomechanical heater test in Yucca Mountain

    International Nuclear Information System (INIS)

    Ramirez, A.; Daily, W.; Buettner, M.; LaBrecque, L

    1996-01-01

    A test is being conducted in the densely welded Topopah Springs tuff within Yucca Mountain, Nevada to study the thermomechanical and hydrological behavior of this horizon when it is heated. A single 4 kW heater, placed in a horizontal borehole, was turned on August, 1996 and will continue to heat the rockmass until April 1997. Of the several thermal, mechanical and hydrological measurements being used to monitor the rockmass response, electrical resistance tomography (ERT) is being used to monitor the movement of liquid water with a special interest in the movement of condensate out of the system. Four boreholes, containing a total of 30 ERT electrodes, were drilled to form the sides of a 30 foot square with the heater at the center and perpendicular to the plane. Images of resistivity change were calculated using data collected before and during the heating episode. The changes recovered show a region of decreasing resistivity approximately centered around the heater. The size this region grows with time and -the resistivity decreases become stronger. The changes in resistivity are caused by both temperature and saturation changes. The observed resistivity changes suggest that the rock adjacent to the heater dries as heating progresses. This dry region is surrounded by a region of increased saturation where steam recondenses and imbibes into the rock

  3. Influence of local air velocity from air conditioner evaluated by salivary and skin biomarkers

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, Masaki; Takahashi, Takayuki; Yoshino, Yuichiro; Sasaki, Makoto [Graduate School of Engineering, Iwate University, 4-3-5 Ueda, Morioka 020-8551 (Japan); Nishimiya, Hajime [Asahi Kasei Homes Corporation, R and D Laboratories, 2-1 Samejima, Fuji, Shizuoka 416-8501 (Japan)

    2010-11-15

    The purpose of this paper is to reveal both the psychosomatic and the physical effects of local air velocity from an air conditioner using biomarkers which can be collected noninvasively. Salivary {alpha}-amylase activity (SAA) and salivary cortisol were used as the indexes of psychosomatic effects. The total protein (TP) collected from stratum corneum was used as an index of the physical condition of dry skin. A continuous experiment over a 5 days period in summer was conducted using 8 healthy young male adults for 2-types of airflow conditioners, a whole ceiling-type air conditioner (without local air velocity) and a normal-type air conditioner (with local air velocity). The subjects felt cool, windy, dry and uncomfortable when under the normal-type air conditioner as determined in a subjective evaluation. The SAA under the normal-type air conditioner fluctuated more widely than with the whole ceiling-type air conditioner. The level of salivary cortisol decreased more in a day under the normal-type air conditioner than with the whole ceiling-type air conditioner. These results showed that reducing local air velocity may provide more healthy psychosomatic conditions over the long-term. Moreover, the TP of a drying-exposed skin area showed a significant change during this experiment whereas the TP of drying-protected area was relatively unchanged. It was indicated that one week's exposure to local air velocity conditions possibly influences the drying of facial skin. Thus, air movement at low velocity can be provides more comfortable conditions not only psychosomatically but also physically. (author)

  4. Current Evaluation Procedures for Fertilizers and Soil Conditioners Used in Organic Agriculture. Proceedings of a workshop held April 29–30, 2004 at Emerson College, Great Britain

    OpenAIRE

    Canali, Stefano; Stopes, Christopher; Schmid, Otto; Speiser, Bernhard

    2005-01-01

    Table of Contents Fertilizers and soil conditioners in organic farming in Austria Alexandra Hozzank and Wilfried Hartl Fertilizers and soil conditioners in organic farming in the Czech Republic Anamarija Slabe Fertilizers and soil conditioners in organic farming in Denmark Rasmus Ørnberg Eriksen and Erik Steen Kristensen Fertilizers and soil conditioners in organic farming in France Marie-Christine Monnier Fertilizers and soil conditioners in organic fa...

  5. Evaluation of radiofrequency dielectric heaters workers exposure

    International Nuclear Information System (INIS)

    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. (authors)

  6. Radioisotopic heater units warm an interplanetary spacecraft

    International Nuclear Information System (INIS)

    Franco-Ferreira, E.A.

    1998-01-01

    The Cassini orbiter and Huygens probe, which were successfully launched on October 15, 1997, constitute NASA's last grand-scale interplanetary mission of this century. The mission, which consists of a four-year, close-up study of Saturn and its moons, begins in July 2004 with Cassini's 60 orbits of Saturn and about 33 fly-bys of the large moon Titan. The Huygens probe will descend and land on Titan. Investigations will include Saturn's atmosphere, its rings and its magnetosphere. The atmosphere and surface of Titan and other icy moons also will be characterized. Because of the great distance of Saturn from the sun, some of the instruments and equipment on both the orbiter and the probe require external heaters to maintain their temperature within normal operating ranges. These requirements are met by Light Weight Radioisotope Heater Units (LWRHUs) designed, fabricated and safety tested at Los Alamos National Laboratory, New Mexico. An improved gas tungsten arc welding procedure lowered costs and decreased processing time for heat units for the Cassini spacecraft

  7. Improvement of reliability of heater and condenser

    International Nuclear Information System (INIS)

    Yamagishi, Hiroki

    1988-01-01

    Recently, the diversification of the operation modes of power plants has advanced as well as daily start and stop and weekly start and stop operations, as the result, the needs for the reliability improvement of various heat exchangers around steam turbines heighten. In newly constructed plants, the design to meet this demand is carried out, but also in existing platns, the application of the latest technology is investigated. As for the reliability of condensers, aluminum brass cooling tubes have been used by doing the optimal maintenance and taking the measures against deposit attack. In the case of requiring high reliability, the examples of adopting titanium cooling tubes increased. The technology of titanium tube condensers, completely assembled condensers, the replacement of existing brass tubes with titanium tubes and so on are discussed. In the case of feed heaters, the deterioration phenomena due to the lapse of long years, such as the attack of steel tube inlet, the drain attack on the external surfaces of steel tubes, the ammonia attack of aluminum brass tubes and the adhesion of scale to heaters, are explained, and the countermeasures are shown. (Kako, I.)

  8. Substantial energy conservation in air conditioners; Substantiele energiebesparing bij luchtbehandelingsinstallaties

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-03-01

    An air conditioner has been retrofitted by application of an optimized fan in combination with an EC motor (brushless dc-motor). Attention is paid to the difference between an AC- and and EC motor, between free-running and spiral housing fans, between direct or indirect-driven, and between forward-bended and backward-bended blades. By means of equations and diagrams the realized energy conservation is visualized. [Dutch] De renovatie van een luchtbehandelingskast wordt besproken. Door de toepassing van ventilatoren met een geoptimaliseerde waaier in combinatie met een EC-motor (borstelloze gelijkstroommotor) wordt een substantiele energiebesparing gerealiseerd. Er wordt op verschillende aspecten ingegaan. Onder meer het verschil tussen een AC- en EC-motor, tussen vrijlopende en slakkenhuisventilatoren, tussen direct- of indirect-gedreven schoepen en tussen voorwaarts- of achterwaartsgebogen schoepen. Aan de hand van vergelijkingen en diagrammen wordt de energiewinst zichtbaar gemaakt.

  9. Computational analysis of the flow field downstream of flow conditioners

    Energy Technology Data Exchange (ETDEWEB)

    Erdal, Asbjoern

    1997-12-31

    Technological innovations are essential for maintaining the competitiveness for the gas companies and here metering technology is one important area. This thesis shows that computational fluid dynamic techniques can be a valuable tool for examination of several parameters that may affect the performance of a flow conditioner (FC). Previous design methods, such as screen theory, could not provide fundamental understanding of how a FC works. The thesis shows, among other things, that the flow pattern through a complex geometry, like a 19-hole plate FC, can be simulated with good accuracy by a k-{epsilon} turbulence model. The calculations illuminate how variations in pressure drop, overall porosity, grading of porosity across the cross-section and the number of holes affects the performance of FCs. These questions have been studied experimentally by researchers for a long time. Now an understanding of the important mechanisms behind efficient FCs emerges from the predictions. 179 ref., 110 figs., 8 tabs.

  10. Radio decontamination of hair conditioner for capillary ammniotherapy

    International Nuclear Information System (INIS)

    Romay, Z.; Otero, I.; Chavez, A.; Torriente, I.

    1996-01-01

    The Hair conditioner, which belongs to the group of cosmetic products Dr Miyares Cao, was artificially contaminated, kept at different values of temperature (-20 oC , 0 oC and +20 oC ) and irradiated to different doses (6, 10, 12, 15, 20, 25 and 30 kGy) and 25 oC for studying the effect of gamma radiation on it and the possibility of use of this technology for its decontamination. The radiobiological parameters of the contaminator and the quality of irradiated products were determined. Was conclude that the product maintain its organolepthics characteristics and others quality parameters after irradiated to 20 kGy and +20 oC of temperature before irradiation. Finally, the decontamination of studied product was obtained by means its irradiation to 16.2 kGy

  11. 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.

  12. Survey costs associated with the replacement of electric showers for solar heaters

    International Nuclear Information System (INIS)

    Belchior, Fernando Nunes; Araujo, Jose Euripedes de

    2010-01-01

    This paper aims to explain the benefits of replacing electric shower for solar water heaters, and a consequent drop in peak demand for electric power generation and residential consumption in the economy. For this, will be shown the lifting of solar radiation per square meter in Brazil, studied in 250 locations, the most representative in terms of solar energy in this country. The costs presented are associated with replacement of 5 million, 10 million and 20 million electric showers. (author)

  13. Effectiveness of finish materials and room air-conditioner on the reduction of indoor radon concentration in Hong Kong

    International Nuclear Information System (INIS)

    Ma, A.K.; Man, C.K.; Ho, E.; Pang, S.W.

    1995-01-01

    Four different kinds of finish material were investigated: wallpaper, paint, plaster and tile. When applied to the bare concrete walls of uninhabited rooms in flats of a building under construction, all of them were found to reduce indoor radon concentration. The magnitude of reduction by these finish materials ranged from 20% to 80%. Wallpaper was found to provide the best protection against radon emission from bare concrete walls in a bedroom with a size of 19.3 m 3 . Wallpaper can reduce the indoor radon concentration about twice as much as paint (water-based) or plaster in this investigation. Tile was also found to be a good material against radon emission from concrete walls in a bathroom with a size of 6.3 m 3 . Indoor radon concentration was found to decrease with elevation from the ground level, and was affected strongly by mechanical ventilation. Another 30% to 50% reduction in indoor radon concentration in addition to finish material can be achieved by a room air-conditioner. It was also found that indoor radon concentrations were not affected by turning the fresh air shutter to the 'on' or 'off' position in the room air-conditioner. (author)

  14. ENERGY STAR Certified Non-AHRI Central Air Conditioner Equipment and Air Source Heat Pump

    Data.gov (United States)

    U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 5.0 ENERGY STAR Program Requirements for Air Source Heat Pump and Central Air Conditioner...

  15. 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.

  16. DEMONSTRATION AND TESTING OF AN EER OPTIMIZER SYSTEM FOR DX AIR-CONDITIONERS

    Science.gov (United States)

    2017-10-07

    Conditioner and Any Web Connected Device Such as a Tablet, Phone, Laptop, or Desktop Computer. ............. 28  Figure 15. A Summary Screen Showing...efficiency specifications published by the Consortium for Energy Efficiency (CEEE) for new unitary air conditioning and heat pump systems5 establish Energy...Figure 14. Connection Diagram Showing Data Path between the Air Conditioner and Any Web Connected Device Such as a Tablet, Phone, Laptop, or Desktop

  17. Energy and economic analysis of a building air-conditioner with a phase change material (PCM)

    International Nuclear Information System (INIS)

    Chaiyat, Nattaporn

    2015-01-01

    Highlights: • Phase change material of Rubitherm20 was applied with the air-conditioner under the climate of Thailand. • PCM was used to reduce cooling load and electrical power of the air-conditioner. • Mathematical model of the packed ball bed of PCM was presented to predict the thermal performance. - Abstract: In this study, a concept of using phase change material (PCM) for improving cooling efficiency of an air-conditioner had been presented under Thailand climate. Rubitherm20 (RT-20) was selected to evaluate the thermal performance by reducing the air temperature entering the evaporating coil. The model of PCM celluloid balls had been performed with the air-conditioner. For the experiment, 2 TR of R-134a air-conditioner was chosen to test a pack bed of PCM balls with thickness 40 cm. The pressure drops of the air flowing through the bed were considered with and without a set of by-pass tubes along the height of the storage bed. The mathematical model of the air-conditioner with the PCM storage was developed and verified with the testing results. From the study results, it could be seen that pressure drops of the bed with and without bypass tubes were nearly the same results. Thus, PCM ball pack bed using RT-20 without bypass tubes was used to improve the cooling efficiency of the air-conditioner. The experimental result of the modified unit was compared and verified with the mathematical model, which agreed quite well with the simulation result. Finally, the model was used to analyze the economic result, which found that the electrical consumption of the modified air-conditioner could be decreased around 3.09 kW h/d. The saving cost from the PCM bed could be 9.10% of 170.03 USD/y and the payback period was around 4.15 y

  18. Use of expanded vermiculite as a soil conditioner in the tropics

    International Nuclear Information System (INIS)

    Libardi, P.L.; Salati, E.; Reichardt, K.

    1983-01-01

    Expanded vermiculite is used as a soil conditioner to improve soil-water retention and cation exchange properties of poor tropical soils (alfisols and oxisols). Results show that fresh laboratory mixtures of soil and expanded vermiculite increase the amount of water retained, the process being affected by the rate of application, origin and granule size of the vermiculite. Pot experiments show that the incorporation of vermiculite into the soil increases soil-water storage capacity without affecting evapotranspiration rates. This indicates that crops grown in soils conditioned with vermiculite lose the same quantities of water through evapotranspiration, but support plants for longer periods without water addition. Diminishing irrigation frequency raises the possibility of irrigating larger areas and/or using irrigation equipment more rationally. Field experiments have been developed to examine the potential use of vermiculite, at low application rates, in extensive agriculture. Encouraging results have been obtained regarding crop resistance to drought spells, and yield in vermiculite conditioned soils. This new management practice seems to be one solution for semi-arid agriculture and for areas of soil with poor water retention properties subjected to irregular rainfall patterns. Experiments show also that vermiculite addition improves root growth and affects soil nutrient ratios. This depends again on soil type, vermiculite origin and granule size, application rates, form of incorporation into the soil and type of crop. It affects Ca/K, Ca/Mg and Mg/K ratios in soil extracts and the availability of micronutrients. Tracers were used to study some aspects of the dynamics of N and P. (author)

  19. Integrity Assessment of GOH Heater Tube

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Bong Sang; Hong, J. H.; Oh, Y. J.; Yoon, J. H.; Oh, J. M. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1997-08-01

    An assessment of structural integrity of ASTM A312-TP347 GOH heater tube was performed. The surface notches which had been produced during tube manufacturing process were analyzed microscopically. Chemical analysis, hardness tests, tensile tests, and J-Integral fracture resistance tests were carried out to compare the mechanical properties with those of the material specification and also with the other material of the same type. The test results showed the mechanical properties of the GOH tube material are within the specification range. An elastic-plastic fracture mechanics analysis based on the DPFAD method reveals the tube an appropriate safety margin for the normal operation. 13 refs., 5 tabs., 24 figs. (author)

  20. 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.

  1. Improvement of Cooling Performance of a Compact Thermoelectric Air Conditioner Using a Direct Evaporative Cooling System

    Science.gov (United States)

    Tipsaenporm, W.; Lertsatitthanakorn, C.; Bubphachot, B.; Rungsiyopas, M.; Soponronnarit, S.

    2012-06-01

    This paper presents the results of tests carried out to investigate the potential application of a direct evaporative cooling (DEC) system for improving the performance of a compact thermoelectric (TE) air conditioner. The compact TE air conditioner is composed of three TE modules. The cold and hot sides of the TE modules were fixed to rectangular fin heat sinks. The DEC system produced cooling air that was used to assist the release of heat from the heat sinks at the hot side of the TE modules. The results showed that the cooling air dry bulb temperature from the DEC system achieved drops of about 5.9°C in parallel with about a 33.4% rise in relative humidity. The cooling efficiency of the DEC system varies between 72.1% and 81.5%. It increases the cooling capacity of the compact TE air conditioner from 53.0 W to 74.5 W. The 21.5 W (40.6%) increase represents the difference between the compact air conditioner operating with ambient air flowing through the TE module's heat sinks, and the compact air conditioner operating with the cooler air from the DEC system flowing through the TE module's heat sinks. In both scenarios, electric current of 4.5 A was supplied to the TE modules. It also has been experimentally proven that the coefficient of performance (COP) of the compact TE air conditioner can be improved by up to 20.9% by incorporating the DEC system.

  2. Electrical heaters for thermo-mechanical tests at the Stripa mine

    International Nuclear Information System (INIS)

    Burleigh, R.H.; Binnall, E.P.; DuBois, A.O.; Norgren, D.U.; Ortiz, A.R.

    1979-01-01

    Electrical heaters were installed at the Stripa mine in Sweden to simulate the heat flux expected from canisters containing nuclear waste. Three heater types were designed and fabricated: two full scale heaters, 2.6 m in length and 324 mm in diameter, supplying a maximum power output of 5 kW; eight peripheral heaters of 25 mm diameter, supplying 1.1 kW; and eight time scale heaters, one-third the size and power of the full scale heaters. The heater power can be monitored by panel meters as well as by a computer-based data acquisition system. Both the controller and the heater were designed with a high degree of redundancy in case of component failure. Auxiliary items were provided with the heaters to monitor borehole decrepitation and heater temperature, and to dewater the heater holes. This report describes the above systems and relates experience gained during testing, installation, and operation

  3. Analysis of polymer foil heaters as infrared radiation sources

    International Nuclear Information System (INIS)

    Witek, Krzysztof; Piotrowski, Tadeusz; Skwarek, Agata

    2012-01-01

    Infrared radiation as a heat source is used in many fields. In particular, the positive effect of far-infrared radiation on living organisms has been observed. This paper presents two technological solutions for infrared heater production using polymer-silver and polymer-carbon pastes screenprinted on foil substrates. The purpose of this work was the identification of polymer layers as a specific frequency range IR radiation sources. The characterization of the heaters was determined mainly by measurement of the surface temperature distribution using a thermovision camera and the spectral characteristics were determined using a special measuring system. Basic parameters obtained for both, polymer silver and polymer carbon heaters were similar and were as follows: power rating of 10–12 W/dm 2 , continuous working surface temperature of 80–90 °C, temperature coefficient of resistance (TCR) about +900 ppm/K for polymer-carbon heater and about +2000 ppm/K for polymer-silver, maximum radiation intensity in the wavelength range of 6–14 μm with top intensity at 8.5 μm and heating time about 20 min. For comparison purposes, commercial panel heater was tested. The results show that the characteristics of infrared polymer heaters are similar to the characteristics of the commercial heater, so they can be taken into consideration as the alternative infrared radiation sources.

  4. Heater experiments in the Climax Stock, Nevada Test Site

    International Nuclear Information System (INIS)

    Ramspott, L.; Ballou, L.

    1977-01-01

    The Climax Stock is a composite granitic intrusive at the Nevada Test Site, with an existing shaft and an open drift about 1400 ft. below the surface. In September 1977, the Lawrence Livermore Laboratory plans to operate three in-situ heater experiments in this area. The first experiment consists of a single heater surrounded by thermocouples at distances of from 1/10 to 5 meters. The close spacing will scale down the time required for useful thermal measurements. The heater, which is 3 meters long and capable of about 3 kW, will be energized for a month, turned off for a month, and the cycle repeated. The rock surface temperature in the heater hole is not expected to exceed 500 to 600 0 C, and the temperature beyond 0.1 m into the rock is not expected to exceed 400 0 C. Measurements will be taken during all four months. These measurements will be compared with numerical simulations to determine the thermal properties of the medium. The second experiment, also involving only a single heater, will be more completely instrumented to include the measurement of permeability, rock displacement, stress/strain, and possibly acoustic emission measurements. The scale of the experiment will be larger, and the heater will be energized continuously for about 4 months. The third test in the series is envisioned to be a scale-up of the second, except that multiple heaters will be used. These heaters will be energized for about a year. They will be arranged around a pillar structure left in the room to obtain information on mine stability in the presence of multiple heaters

  5. Test results and supporting analysis of a near-surface heater experiment in the Eleana argillite

    International Nuclear Information System (INIS)

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

    1979-01-01

    A preliminary evaluation of the in-situ thermomechanical response of argillite to heating was obtained from a near-surface heater test in the Eleana Formation, at the United States Department of Energy, Nevada Test Site. The experiment consisted of a 3.8 kW, 3-m long x 0.3-m diameter electrical heater in a central hole surrounded by peripheral holes containing instrumentation to measure temperature, gas pressures, and vertical displacement. A thermal model of the experiment agreed well with experimental results; a comparison of measured and predicted temperatures indicates that some nonmodeled vertical transport of water and water vapor occurred near the heater, especially at early times. A mechanical model indicated that contraction of expandable clays in the argillite produced a region 1.5 - 2.0 m in radius, in which opening of preexisting joints occurred as a result of volumetric contraction. Results of thermal and mechanical modeling, laboratory property measurements, experimental temperature measurements, and post-test observations are all self-consistent and provide preliminary information on the in-situ response of argillaceous rocks to the emplacement of heat-producing nuclear waste

  6. A visual study of forced convection boiling. Part I: Results for a flat vertical heater

    International Nuclear Information System (INIS)

    Kirby, G.J.; Staniforth, R.; Kinneir, J.H.

    1965-03-01

    This report presents the first results of a visual study of the hydrodynamics of boiling in channels and of burnout. It was found that the bubbles formed did not diffuse into the main stream at high heat fluxes, but remained close to the heater. Consequently severe coalescence took place, resulting in the formation of large regularly shaped bubbles. An analysis of the forces acting on these bubbles is given; this accounts qualitatively for the observed behaviour. The above bubble formations result from the addition of heat at a wall so that clearly isothermal models, such as those using air-water mixtures, cannot give a true representation of the flow pattern. Attempts to view the heater surface at burnout were frustrated by poor visibility through the boiling mixture. (author)

  7. Thermal behaviour of solar air heater with compound parabolic concentrator

    International Nuclear Information System (INIS)

    Tchinda, Rene

    2008-01-01

    A mathematical model for computing the thermal performance of an air heater with a truncated compound parabolic concentrator having a flat one-sided absorber is presented. A computer code that employs an iterative solution procedure is constructed to solve the governing energy equations and to estimate the performance parameters of the collector. The effects of the air mass flow rate, the wind speed and the collector length on the thermal performance of the present air heater are investigated. Predictions for the performance of the solar heater also exhibit reasonable agreement, with experimental data with an average error of 7%

  8. Implementation of heaters on thermally actuated spacecraft mechanisms

    Science.gov (United States)

    Busch, John D.; Bokaie, Michael D.

    1994-01-01

    This paper presents general insight into the design and implementation of heaters as used in actuating mechanisms for spacecraft. Problems and considerations that were encountered during development of the Deep Space Probe and Science Experiment (DSPSE) solar array release mechanism are discussed. Obstacles included large expected fluctuations in ambient temperature, variations in voltage supply levels outgassing concerns, heater circuit design, materials selection, and power control options. Successful resolution of these issues helped to establish a methodology which can be applied to many of the heater design challenges found in thermally actuated mechanisms.

  9. Thermally driven self-healing using copper nanofiber heater

    Science.gov (United States)

    Lee, Min Wook; Jo, Hong Seok; Yoon, Sam S.; Yarin, Alexander L.

    2017-07-01

    Nano-textured transparent heaters made of copper nanofibers (CuNFs) are used to facilitate accelerated self-healing of bromobutyl rubber (BIIR). The heater and BIIR layer are separately deposited on each side of a transparent flexible polyethylene terephthalate (PET) substrate. A pre-notched crack on the BIIR layer was bridged due to heating facilitated by CuNFs. In the corrosion test, a cracked BIIR layer covered a steel substrate. An accelerated self-healing of the crack due to the transparent copper nanofiber heater facilitated an anti-corrosion protective effect of the BIIR layer.

  10. Low cost solar array project silicon materials task. Development of a process for high capacity arc heater production of silicon for solar arrays

    Science.gov (United States)

    Fey, M. G.

    1981-01-01

    The experimental verification system for the production of silicon via the arc heater-sodium reduction of SiCl4 was designed, fabricated, installed, and operated. Each of the attendant subsystems was checked out and operated to insure performance requirements. These subsystems included: the arc heaters/reactor, cooling water system, gas system, power system, Control & Instrumentation system, Na injection system, SiCl4 injection system, effluent disposal system and gas burnoff system. Prior to introducing the reactants (Na and SiCl4) to the arc heater/reactor, a series of gas only-power tests was conducted to establish the operating parameters of the three arc heaters of the system. Following the successful completion of the gas only-power tests and the readiness tests of the sodium and SiCl4 injection systems, a shakedown test of the complete experimental verification system was conducted.

  11. Comparative Studies of the Operation Method of Solar Energy Water Heating System with Auxiliary Heat Pump Heater%热泵辅助供热太阳能热水系统运行模式对比分析

    Institute of Scientific and Technical Information of China (English)

    林辩启; 罗会龙; 王浩; 田盼雨

    2015-01-01

    太阳能热水系统与热泵辅助供热合理结合可取长补短,有效降低建筑能耗。简要概述了空气源热泵、水源热泵、地源热泵辅助供热太阳能热水系统的结构形式及其运行模式。在此基础上,对比分析了热泵辅助供热太阳能热水系统各种典型运行模式的特点及其适用的应用环境。%The appropriate combination of solar water heating system and heat pump auxiliary heating is an effective way to reduce the building energy consumption. The structure and operation method of solar water heating system with different auxiliary heating, such as air-source heat pump, water-source heat pump, and soil-source heat pump, were introduced briefly. The characteristics of all kinds of solar water heating system with auxiliary heating were compared and analyzed. The suitable application environment of solar water heating system with auxiliary heating was also presented.

  12. Large-scale in situ heater tests for hydrothermal characterization at Yucca Mountain

    International Nuclear Information System (INIS)

    Buscheck, T.A.; Wilder, D.G.; Nitao, J.J.

    1993-01-01

    To safely and permanently store high-level nuclear-waste, the potential Yucca Mountain repository site must mitigate the release and transport of radionuclides for tens of thousands of years. In the failure scenario of greatest concern, water would contact a waste package, accelerate its failure rate, and eventually transport radionuclides to the water table. Our analysis indicate that the ambient hydrological system will be dominated by repository-heat-driven hydrothermal flow for tens of thousands of years. In situ heater tests are required to provide an understanding of coupled geomechanical-hydrothermal-geochemical behavior in the engineered and natural barriers under repository thermal loading conditions. In situ heater tests have been included in the Site Characterization Plan in response to regulatory requirements for site characterization and to support the validation of process models required to assess the total systems performance at the site. The success of the License Application (LA) hinges largely on how effectively we validate the process models that provide the basis for performance assessment. Because of limited time, some of the in situ tests will have to be accelerated relative to actual thermal loading conditions. We examine the trade-offs between the limited test duration and generating hydrothermal conditions applicable to repository performance during the entire thermal loading cycle, including heating (boiling and dry-out) and cooldown (re-wetting). For in situ heater tests duration of 6-7 yr (including 4 yr of full-power heating) is required. The parallel use of highly accelerated, shorter-duration tests may provide timely information for the LA, provided that the applicability of the test results can be validated against ongoing nominal-rate heater tests

  13. Development of a solar-powered residential air conditioner: Screening analysis

    Science.gov (United States)

    1975-01-01

    Screening analysis aimed at the definition of an optimum configuration of a Rankine cycle solar-powered air conditioner designed for residential application were conducted. Initial studies revealed that system performance and cost were extremely sensitive to condensing temperature and to the type of condenser used in the system. Consequently, the screening analyses were concerned with the generation of parametric design data for different condenser approaches; i. e., (1) an ambient air condenser, (2) a humidified ambient air condenser (3) an evaporative condenser, and (4) a water condenser (with a cooling tower). All systems feature a high performance turbocompressor and a single refrigerant (R-11) for the power and refrigeration loops. Data were obtained by computerized methods developed to permit system characterization over a broad range of operating and design conditions. The criteria used for comparison of the candidate system approaches were (1) overall system COP (refrigeration effect/solar heat input), (2) auxiliary electric power for fans and pumps, and (3) system installed cost or cost to the user.

  14. Meloidogyne javanica control by Pochonia chlamydosporia, Gracilibacillus dipsosauri and soil conditioner in tomato

    Directory of Open Access Journals (Sweden)

    Guilherme Silva de Podestá

    2013-06-01

    Full Text Available Organic matter plays a fundamental role in the antagonistic activity of microorganisms against phytonematode populations on the soil. In this study, the compatibility between the fungus Pochonia chlamydosporia (Pc-12 and the rhizobacterium Gracilibacillus dipsosauri (MIC 14 was evaluated in vitro, as well as the effect of the fungus at the concentration of 5,000 chlamydospores per gram of soil, rhizobacterium at 4.65 x 10(9 cells/g of soil, and the soil conditioner Ribumin® at 10 g/pot, either alone or in combination, against Meloidogyne javanica population in tomato plants (3,000 eggs/pot. A suspension of water or Ribumin® alone was applied on the soil as negative control, while a suspension of nematode eggs was applied as positive control. The reduction in the number of galls in roots per plant was 48 and 41% for the treatments Ribumin + MIC 14 + Pc-12 and MIC 14 + Pc-12, respectively. Regarding to the number of eggs per plant, MIC 14 and Pc-12 + Ribumin led to a reduction by 26 and 21%, respectively, compared to the control treatment. Interaction between the nematophagous fungus and the rhizobacterium was positive for the nematode control, even though G. dipsosauri inhibited P. chlamydosporia growth by up to 30% in in vitro tests.

  15. The life cycle rebound effect of air-conditioner consumption in China

    International Nuclear Information System (INIS)

    Liu, Jingru; Sun, Xin; Lu, Bin; Zhang, Yunkun; Sun, Rui

    2016-01-01

    Highlights: • Develop a life cycle rebound effect model. • Assess the life cycle rebound effect of Chinese room air conditioners. • Conduct a questionnaire to assess the consumption behavior of Chinese room air conditioners. • Rebound effect should be considered by energy policy makers. - Abstract: Governments worldwide are attempting to reduce energy consumption and environmental pollution by confronting environmental problems and adopting more energy-efficient products. However, because of the rebound effect, energy-saving targets cannot always be fully achieved, and sometimes greater energy consumption is generated. Research on the rebound effect from the perspective of industrial ecology considers not only direct energy consumption but also its life cycle negative impacts on the environment with China’s rapid economic development and simultaneously improving quality of life, the ownership of room air conditioners (RACs) has increased more than three hundred times, and air conditioners’ energy consumption has increased one thousand times over the last twenty years. The Air Conditioner Energy Efficiency Standard is one of the most important measures in China for reducing the amount of energy consumed by RACs. This paper introduces a life cycle based method to estimate the rebound effect of Chinese RACs consumption. This model provides a product’s life-cycle view to assess the rebound effect, considering the contribution of both producer and consumer. Based on the established life cycle rebound effect model, we compared urban household RAC consumption behaviour before and after the launch of the Air Conditioner Energy Efficiency Standard. A rebound effect in RAC consumption was found that there was a longer daily usage period in the household as air conditioner efficiency levels improved. The life cycle rebound effect of household air-conditioner consumption was calculated to be 67%. The main conclusion obtained from this study is that policies and

  16. PWR pressurizer with heaters well which can be obturate and sealing process

    International Nuclear Information System (INIS)

    Godin, B.; Guicherd, L.

    1991-01-01

    Each heater well is prolongated at the end located outer the pressurizer containment by a sleeve internally tapped which is prolongated at the other end by a guiding and fixation sleeve for welding the heater. The heater well can be obturated by a threaded plug introduce in the tapped part of the sleeve after cutting the welding sleeve and extraction of the heater [fr

  17. 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..., and Institutional Boilers and Process Heaters General Compliance Requirements § 63.7506 Do any boilers or process heaters have limited requirements? (a) New or reconstructed boilers and process heaters in...

  18. 40 CFR 63.7491 - Are any boilers or process heaters not subject to this subpart?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 13 2010-07-01 2010-07-01 false Are any boilers or process heaters not..., and Institutional Boilers and Process Heaters What This Subpart Covers § 63.7491 Are any boilers or process heaters not subject to this subpart? The types of boilers and process heaters listed in paragraphs...

  19. Thermoeconomic optimization of small size central air conditioner

    International Nuclear Information System (INIS)

    Zhang, G.Q.; Wang, L.; Liu, L.; Wang, Z.

    2004-01-01

    The application of thermoeconomic optimization design in an air-conditioning system is important in achieving economical life cycle cost. Previous work on thermoeconomic optimization mainly focused on directly calculating exergy input into the system. However, it is usually difficult to do so because of the uncertainty of input power of fan on the air side of the heat-exchanger and that of pump in the system. This paper introduces a new concept that exergy input into the system can be substituted for the sum of exergy destruction and exergy output from the system according to conservation of exergy. Although it is also difficult for a large-scale system to calculate exergy destruction, it is feasible to do so for a small-scale system, for instance, villa air conditioner (VAC). In order to perform thermoeconomic optimization, a program is firstly developed to evaluate the thermodynamic property of HFC134a on the basis of Martin-Hou state equation. Authors develop thermodynamic and thermoeconomic objective functions based on second law and thermoeconomic analysis of VAC system. Two optimization results are obtained. The design of VAC only aimed at decreasing the energy consumption is not comprehensive. Life cycle cost at thermoeconomic optimization is lower than that at thermodynamic optimization

  20. solar dryer with biomass backup heater for drying fruits

    African Journals Online (AJOL)

    SOLAR DRYER WITH BIOMASS BACKUP HEATER FOR DRYING FRUITS: DEVELOPMENT AND PERFORMANCE ANALYSIS. ... Journal of Science and Technology (Ghana) ... Most solar dryers rely on only solar energy as the heat source.