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Sample records for space heating domestic

  1. Solar system for domestic hot water and space heating

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, W. [Arbeitsgemeinschaf Erneubare Energie, Gleisdorf (Austria)

    1997-12-31

    The solar thermal markets, different types of solar systems for hot water and space heating, the dimensioning and the components of solar heating systems, the properties of the systems are reviewed in this presentation

  2. Solar system for domestic hot water and space heating

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, W [Arbeitsgemeinschaf Erneubare Energie, Gleisdorf (Austria)

    1998-12-31

    The solar thermal markets, different types of solar systems for hot water and space heating, the dimensioning and the components of solar heating systems, the properties of the systems are reviewed in this presentation

  3. Investigation af a solar heating system for space heating and domestic hot water supply with a high degree of coverage

    DEFF Research Database (Denmark)

    Vejen, Niels Kristian

    1999-01-01

    A solar storage tank for space heating and domestic hot water supply was designed and testet in af laboratory test facility.......A solar storage tank for space heating and domestic hot water supply was designed and testet in af laboratory test facility....

  4. Measure Guideline. Combination Forced-Air Space and Tankless Domestic Hot Water Heating Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rudd, Armin [Building Science Corporation Industry Team (BSC), Somerville, MA (United States)

    2012-08-01

    This document describes design and application guidance for combination space and tankless domestic hot water heating systems (combination systems) used in residential buildings, based on field evaluation, testing, and industry meetings conducted by Building Science Corporation. As residential building enclosure improvements continue to drive heating loads down, using the same water heating equipment for both space heating and domestic water heating becomes attractive from an initial cost and space-saving perspective. This topic is applicable to single- and multi-family residential buildings, both new and retrofitted.

  5. Practical versus theoretical domestic energy consumption for space heating

    International Nuclear Information System (INIS)

    Audenaert, A.; Briffaerts, K.; Engels, L.

    2011-01-01

    Methods to calculate the theoretical energy consumption consider several things: the number of degree days per year that need to be compensated by heating, the characteristics of the dwelling, the number of occupants and the characteristics of the installation for space heating and sanitary hot water. However, these methods do not take into account consumer behaviour, which may affect the actual consumption. The theoretical calculation methods are based on assumptions and use a number of standardized parameters. The difference between the actual and the theoretical energy consumption, and the impact of the residents' behaviour on energy consumption, is analysed by means of a literature study and a practical research. An energy advice procedure (EAP) audit is executed in five dwellings, as well as a survey regarding the energy related behaviour of the households. The theoretically calculated consumption is compared with the billed actual energy consumption of the families. The results show some problems with the current procedure and give some options to improve it. Some research needs are identified to gain more insights in the influence of different behavioural factors on the actual energy use for heating. - Highlights: → The energy advice procedure (EAP) calculates the energy use for heating in dwellings. → Calculations are compared with the real energy use for 5 dwellings. → A survey on the occupants' behaviour is used to interpret the observed differences. → Default values used in the EAP can be very different from the observed behaviour.

  6. Practical versus theoretical domestic energy consumption for space heating

    Energy Technology Data Exchange (ETDEWEB)

    Audenaert, A., E-mail: amaryllis.audenaert@artesis.be [Department of Applied Engineering: Construction, Artesis University College of Antwerp, Paardenmarkt 92, B-2000 Antwerp (Belgium); Department of Environment, Technology and Technology Management, University of Antwerp, Prinsstraat 13, B-2000 Antwerp (Belgium); Briffaerts, K. [Unit Transition Energy and Environment, VITO NV, Boeretang 200, B-2400 Mol (Belgium); Engels, L. [Department of Applied Engineering: Construction, Artesis University College of Antwerp, Paardenmarkt 92, B-2000 Antwerp (Belgium)

    2011-09-15

    Methods to calculate the theoretical energy consumption consider several things: the number of degree days per year that need to be compensated by heating, the characteristics of the dwelling, the number of occupants and the characteristics of the installation for space heating and sanitary hot water. However, these methods do not take into account consumer behaviour, which may affect the actual consumption. The theoretical calculation methods are based on assumptions and use a number of standardized parameters. The difference between the actual and the theoretical energy consumption, and the impact of the residents' behaviour on energy consumption, is analysed by means of a literature study and a practical research. An energy advice procedure (EAP) audit is executed in five dwellings, as well as a survey regarding the energy related behaviour of the households. The theoretically calculated consumption is compared with the billed actual energy consumption of the families. The results show some problems with the current procedure and give some options to improve it. Some research needs are identified to gain more insights in the influence of different behavioural factors on the actual energy use for heating. - Highlights: > The energy advice procedure (EAP) calculates the energy use for heating in dwellings. > Calculations are compared with the real energy use for 5 dwellings. > A survey on the occupants' behaviour is used to interpret the observed differences. > Default values used in the EAP can be very different from the observed behaviour.

  7. Investigation of a heat storage for a solar heating system for combined space heating and domestic hot water supply for homeowner´s association "Bakken"

    DEFF Research Database (Denmark)

    Vejen, Niels Kristian

    1998-01-01

    A heat storage for a solar heating system for combined space heating and domestic hot water supply was tested in a laboratory test facility.The heat storage consist of a mantle tank with water for the heating system and of a hot water tank, which by means of thermosyphoning is heated by the water...

  8. Non-parametric method for separating domestic hot water heating spikes and space heating

    DEFF Research Database (Denmark)

    Bacher, Peder; de Saint-Aubain, Philip Anton; Christiansen, Lasse Engbo

    2016-01-01

    In this paper a method for separating spikes from a noisy data series, where the data change and evolve over time, is presented. The method is applied on measurements of the total heat load for a single family house. It relies on the fact that the domestic hot water heating is a process generating...

  9. Investigation of a solar heating system for space heating and domestic hot water supply for Sol&Træ A.m.b.a

    DEFF Research Database (Denmark)

    Vejen, Niels Kristian

    1999-01-01

    A solar heating system for space heating and domestic hot water supply from "Sol&Træ A.m.b.a." was tested in a laboratory test facility.......A solar heating system for space heating and domestic hot water supply from "Sol&Træ A.m.b.a." was tested in a laboratory test facility....

  10. Investigation of a low flow solar heating system for space heating and domestic hot water supply for Aidt Miljø A/S

    DEFF Research Database (Denmark)

    Vejen, Niels Kristian

    1997-01-01

    A low flow solar heating system for space heating and domestic hot water supply from Aidt Miljø A/Swas tested in a laboratory test facility.......A low flow solar heating system for space heating and domestic hot water supply from Aidt Miljø A/Swas tested in a laboratory test facility....

  11. A Data Analysis Approach for Diagnosing Malfunctioning in Domestic Space Heating

    NARCIS (Netherlands)

    Tabatabaei, S.

    Around one third of worldwide energy usage is for the residential section and 60% of the energy consumption in this domestic area is for space heating. Therefore, monitoring and controlling this part of energy usage can have a major effect on the overall energy consumption and also on the emission

  12. Heating networks and domestic central heating systems

    Energy Technology Data Exchange (ETDEWEB)

    Kamler, W; Wasilewski, W

    1976-08-01

    This is a comprehensive survey of the 26 contributions from 8 European countries submitted to the 3rd International District Heating Conference in Warsaw held on the subject 'Heating Networks and Domestic Central Heating Systems'. The contributions are grouped according to 8 groups of subjects: (1) heat carriers and their parameters; (2) system of heating networks; (3) calculation and optimization of heating networks; (4) construction of heating networks; (5) operation control and automation; (6) operational problems; (7) corrosion problems; and (8) methods of heat accounting.

  13. Development of space heating and domestic hot water systems with compact thermal energy storage. Compact thermal energy storage: Material development for System Integration

    NARCIS (Netherlands)

    Davidson, J.H.; Quinnell, J.; Burch, J.; Zondag, H.A.; Boer, R. de; Finck, C.J.; Cuypers, R.; Cabeza, L.F.; Heinz, A.; Jahnig, D.; Furbo, S.; Bertsch, F.

    2013-01-01

    Long-term, compact thermal energy storage (TES) is essential to the development of cost-effective solar and passive building-integrated space heating systems and may enhance the annual technical and economic performance of solar domestic hot water (DHW) systems. Systems should provide high energy

  14. Review of biomass fired space heating/domestic hot water boilers' application, operation and design parameters

    International Nuclear Information System (INIS)

    1997-01-01

    Monitoring exercises have been carried out for ETSU, by a number of contractors, on a number of wood fired heating schemes; feasibility studies on proposed schemes have also been carried out. Monitoring reports and feasibility studies have been reviewed to try and establish the suitability and economic viability of the various types of plant used (or proposed) and their application. Of the sixteen schemes reviewed just over 30% showed a reasonable return on the incremental capital cost of plant compared to gas oil fired plant. These schemes had one or more of the following attributes: - Low wood fuel cost -Long operating hours -Relatively low incremental capital cost of wood plant over gas oil plant. Small systems with low operating hours (e.g. short weekday occupancy premises, like schools) and relatively high incremental operating and maintenance costs and capital costs exhibited no advantage over equivalent fossil fuel fired plant. The unit fuel cost advantage to wood, in these cases, was insufficient to outweigh the increased O and M and capital costs, because of the comparatively low annual fuel consumption. Most of the plants reviewed had low thermal efficiencies due to the simplicity of the fuel to air control systems and the wide range of heating demand over which they had to operate. The former can be increased by improved combustion control systems and the latter by correct sizing of boilers and/or the installation of hybrid systems. (Author)

  15. Domestic heating - the biomass challenge

    International Nuclear Information System (INIS)

    Rakos, C.

    1999-01-01

    This article highlights currently available efficient, low emission technical concepts for the combustion of wood, log-burning boilers, woodchip boilers, and the use of wood pellets. The economics of domestic heating with wood, the higher costs incurred with modern efficient wood burners as compared with fuelwood costs, and the proposed European Commission's campaign to implement more wood heated dwellings are discussed, and the transition from traditional to modern wood heating, and options for stimulating growth in renewable energy are considered

  16. Space Heating Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Rafferty, Kevin D.

    1998-01-01

    The performance evaluation of space heating equipment for a geothermal application is generally considered from either of two perspectives: (a) selecting equipment for installation in new construction, or (b) evaluating the performance and retrofit requirements of an existing system. With regard to new construction, the procedure is relatively straightforward. Once the heating requirements are determined, the process need only involve the selection of appropriately sized hot water heating equipment based on the available water temperature. It is important to remember that space heating equipment for geothermal applications is the same equipment used in non-geothermal applications. What makes geothermal applications unique is that the equipment is generally applied at temperatures and flow rates that depart significantly from traditional heating system design. This chapter presents general considerations for the performance of heating equipment at non-standard temperature and flow conditions, retrofit of existing systems, and aspects of domestic hot water heating.

  17. Generation of Domestic Hot Water, Space Heating and Driving Pattern Profiles for Integration Analysis of Active Loads in Low Voltage Grids

    DEFF Research Database (Denmark)

    Diaz de Cerio Mendaza, Iker; Pigazo, Alberto; Bak-Jensen, Birgitte

    2013-01-01

    at household level. Despite of the well-known flexible service that this kind of loads can provide, their flexibility is highly dependent of the domestic hot water and space heating demand and the driving habits of each user. This paper presents two methodologies employed to randomly generate thermal power......The changes in the Danish energy sector, consequence of political agreements, are expected to have direct impact in the actual power distribution systems. Large number of electric boiler, heat pumps and electric vehicles are planned and will cope large percentage of the future power consumption...... demand and electric vehicle driving profiles, to be used for power grid calculations. The generated thermal profiles relied on a statistical analysis made from real domestic hot water and space heating data from 25 households of a typical Danish residential area. The driving profiles instead were formed...

  18. Evaluating energy, health and carbon co-benefits from improved domestic space heating: A randomised community trial

    International Nuclear Information System (INIS)

    Preval, Nick; Chapman, Ralph; Pierse, Nevil; Howden-Chapman, Philippa

    2010-01-01

    In order to value the costs and benefits associated with improved space heating we analysed the Housing, Heating and Health Study, a randomised community trial involving installation of energy efficient and healthy heaters (heat pump, wood pellet burner or flued gas heater) in homes with basic insulation and poor heating, occupied by households which included a child with asthma. We compared the initial purchase and installation cost of heaters with changes in the number of visits to health professionals, time off work/school, caregiving, and pharmaceutical use for household members and changes in total household energy use and carbon emissions following the intervention. We used two scenarios to analyse the results over the predicted 12-year life-span of the heaters. The targeted approach (Scenario A - assuming high rates of household asthma throughout the period of analysis) produced enough health-related benefits to offset the cost of the heaters, and when total energy use and carbon emission savings were included in the analysis the ratio of benefits to costs was 1.09:1. The untargeted approach (Scenario B - assuming typical New Zealand asthma rates throughout the period of analysis) had a ratio of total benefits to costs of 0.31:1.

  19. Evaluating energy, health and carbon co-benefits from improved domestic space heating. A randomised community trial

    Energy Technology Data Exchange (ETDEWEB)

    Preval, Nick; Pierse, Nevil; Howden-Chapman, Philippa [He Kainga Oranga/Housing and Health Research Programme, University of Otago, Wellington, PO Box 7343, Wellington South (New Zealand); Chapman, Ralph [School of Geography, Graduate Programme in Environmental Studies, Environment and Earth Sciences, Victoria University, PO Box 600, Wellington 6140 (New Zealand)

    2010-08-15

    In order to value the costs and benefits associated with improved space heating we analysed the Housing, Heating and Health Study, a randomised community trial involving installation of energy efficient and healthy heaters (heat pump, wood pellet burner or flued gas heater) in homes with basic insulation and poor heating, occupied by households which included a child with asthma. We compared the initial purchase and installation cost of heaters with changes in the number of visits to health professionals, time off work/school, caregiving, and pharmaceutical use for household members and changes in total household energy use and carbon emissions following the intervention. We used two scenarios to analyse the results over the predicted 12-year life-span of the heaters. The targeted approach (Scenario A - assuming high rates of household asthma throughout the period of analysis) produced enough health-related benefits to offset the cost of the heaters, and when total energy use and carbon emission savings were included in the analysis the ratio of benefits to costs was 1.09:1. The untargeted approach (Scenario B - assuming typical New Zealand asthma rates throughout the period of analysis) had a ratio of total benefits to costs of 0.31:1. (author)

  20. Evaluating energy, health and carbon co-benefits from improved domestic space heating: A randomised community trial

    Energy Technology Data Exchange (ETDEWEB)

    Preval, Nick [He Kainga Oranga/Housing and Health Research Programme, University of Otago, Wellington, PO Box 7343, Wellington South (New Zealand); Chapman, Ralph, E-mail: Ralph.chapman@vuw.ac.n [School of Geography, Graduate Programme in Environmental Studies, Environment and Earth Sciences, Victoria University, PO Box 600, Wellington 6140 (New Zealand); Pierse, Nevil; Howden-Chapman, Philippa [He Kainga Oranga/Housing and Health Research Programme, University of Otago, Wellington, PO Box 7343, Wellington South (New Zealand)

    2010-08-15

    In order to value the costs and benefits associated with improved space heating we analysed the Housing, Heating and Health Study, a randomised community trial involving installation of energy efficient and healthy heaters (heat pump, wood pellet burner or flued gas heater) in homes with basic insulation and poor heating, occupied by households which included a child with asthma. We compared the initial purchase and installation cost of heaters with changes in the number of visits to health professionals, time off work/school, caregiving, and pharmaceutical use for household members and changes in total household energy use and carbon emissions following the intervention. We used two scenarios to analyse the results over the predicted 12-year life-span of the heaters. The targeted approach (Scenario A - assuming high rates of household asthma throughout the period of analysis) produced enough health-related benefits to offset the cost of the heaters, and when total energy use and carbon emission savings were included in the analysis the ratio of benefits to costs was 1.09:1. The untargeted approach (Scenario B - assuming typical New Zealand asthma rates throughout the period of analysis) had a ratio of total benefits to costs of 0.31:1.

  1. Control challenges in domestic heating systems

    DEFF Research Database (Denmark)

    Thybo, Honglian; Larsen, Lars F. S.; Weitzmann, Peter

    2007-01-01

    The objective of this paper is to analyze domestic heating applications and identify unfavorable building constructions and control challenges to be addressed by high performance heating control systems. Heating of domestic houses use a large amount of the total energy consumption in Scandinavia....... Hence the potential of reducing energy consumption by applying high performance control is vast. Indoor climate issues are becoming more in focus, which also leads to a demand for high performance heating systems. The paper presents an analysis of how the building elements of today's domestic houses...... with water based floor heating affect the control challenge. The analysis is documented with simulation results....

  2. Chapter 12. Space Heating Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Rafferty, Kevin D.

    1998-01-01

    The performance evaluation of space heating equipment for a geothermal application is generally considered from either of two perspectives: (a) selecting equipment for installation in new construction, or (b) evaluating the performance and retrofit requirements of an existing system. With regard to new construction, the procedure is relatively straightforward. Once the heating requirements are determined, the process need only involve the selection of appropriately sized hot water heating equipment based on the available water temperature. It is important to remember that space heating equipment for geothermal applications is the same equipment used in non-geothermal applications. What makes geothermal applications unique is that the equipment is generally applied at temperatures and flow rates that depart significantly from traditional heating system design. This chapter presents general considerations for the performance of heating equipment at non-standard temperature and flow conditions, retrofit of existing systems, and aspects of domestic hot water heating.

  3. Developing a Magnetocaloric Domestic Heat Pump

    DEFF Research Database (Denmark)

    Bahl, Christian R.H.

    2014-01-01

    beverage coolers, A/Cs for cars and electronics cooling. Devices for heating have not been extensively demonstrated. Here we consider a promising application of magnetocaloric heat pumps for domestic heating. The task of designing and building such a device is a multidisciplinary one encompassing materials...

  4. Central model predictive control of a group of domestic heat pumps, case study for a small district

    NARCIS (Netherlands)

    van Leeuwen, Richard Pieter; Fink, J.; Smit, Gerardus Johannes Maria; Helfert, Markus; Krempels, Karl-Heinz; Donnellan, Brian; Klein, Cornel

    2015-01-01

    In this paper we investigate optimal control of a group of heat pumps. Each heat pump provides space heating and domestic hot water to a single household. Besides a heat pump, each house has a buffer for domestic hot water and a floor heating system for space heating. The paper describes models and

  5. House of Commons No 2027. Proposal of law aiming at applying the reduced AVT rate to the selling and delivery of electricity, gas and fuel oil for domestic space heating use

    International Nuclear Information System (INIS)

    Nicolin, Y.

    2005-01-01

    The aim of this proposal is to apply the same 5.5% reduced added value tax to all energy sources when used for domestic space heating. This reduce tax rate is today only applied to wood wastes and products. (J.S.)

  6. Standard monitoring system for domestic heat pumps

    NARCIS (Netherlands)

    Geelen, C.P.J.M.; Oostendorp, P.A.

    1999-01-01

    In the years to come many domestic heat pump systems are to be installed in the Netherlands. The Dutch agency for energy and environment, NOVEM, and the association of energy utility companies, EnergieNed, give high priority to the monitoring of heat pump systems. The results of the projects,

  7. Cognitive Simulation Driven Domestic Heating Energy Management

    NARCIS (Netherlands)

    Thilakarathne, D.J.; Treur, J.

    2016-01-01

    Energy management for domestic heating is a non trivial research challenge, especially given the dynamics associated to indoor and outdoor air temperatures, required comfortable temperature set points over time, parameters of the heating source and system, and energy loss rate and capacity of a

  8. Emissions from wood domestic heating appliances

    International Nuclear Information System (INIS)

    Collet, S.

    2009-01-01

    Much research has been carried out to study emissions from wood domestic heating appliances. This work reviews the available emission factors about pollutants produced in different types of wood domestic heating appliances. The main sources of pollutants are older stoves that in most cases are used as an additional heating appliance. These stoves causes higher emissions than modern appliances. Then, substitution of an old type wood appliance with a modern appliance or boiler or a pellet boilers, would reduce considerably emissions in this sector. The efficiency of this measure is estimated for each pollutant. (author)

  9. Fuzzy multivariable control of domestic heat pumps

    International Nuclear Information System (INIS)

    Underwood, C.P.

    2015-01-01

    Poor control has been identified as one of the reasons why recent field trials of domestic heat pumps in the UK have produced disappointing results. Most of the technology in use today uses a thermostatically-controlled fixed speed compressor with a mechanical expansion device. This article investigates improved control of these heat pumps through the design and evaluation of a new multivariable fuzzy logic control system utilising a variable speed compressor drive with capacity control linked through to evaporator superheat control. A new dynamic thermal model of a domestic heat pump validated using experimental data forms the basis of the work. The proposed control system is evaluated using median and extreme daily heating demand profiles for a typical UK house compared with a basic thermostatically-controlled alternative. Results show good tracking of the heating temperature and superheat control variables, reduced cycling and an improvement in performance averaging 20%. - Highlights: • A new dynamic model of a domestic heat pump is developed and validated. • A new multivariable fuzzy logic heat pump control system is developed/reported. • The fuzzy controller regulates both plant capacity and evaporator superheat degree. • Thermal buffer storage is also considered as well as compressor cycling. • The new controller shows good variable tracking and a reduction in energy of 20%.

  10. Study of non-domestic applications for active solar heating

    Energy Technology Data Exchange (ETDEWEB)

    Stammers, J.R.

    1997-11-01

    The UK Department of Trade and Industry (through ETSU) commissioned this study as part of its active solar programme. It was carried out from October 1996 to June 1997. The objective was to assess the potential for the use of active solar heating in non-domestic applications. The study was carried out by searching the literature, carrying out case studies and interviewing members of the solar industry and experts in other fields. There are currently about 45-50 active solar non-domestic schemes in operation in the UK, mostly for heating tap water in buildings of different types. The biggest potential for future non-domestic sales also lies in solar water heating for buildings. Most of the opportunities seem to be in the following building types: ablutions blocks in caravan and holiday camps, sheltered flats and hostels, nursing homes, office buildings, hotels and guest houses, and schools occupied during the summer. There are some other building types which might present niche markets for solar water heating. The market for active solar systems in space heating and cooling appears to be negligible. There is one other market for active solar heating in the non-domestic building sector. This is for warming water used to maintain stand-by generators at a temperature which allows them to kick in without delay in the event of a mains power failure. The main market is in buildings housing computers which control the provision of vital services, e.g. electricity, water and gas. (author)

  11. Heat from domestic and industrial wastewater

    International Nuclear Information System (INIS)

    Gasharov, S.

    2006-01-01

    More than 40% of the energy produced in the world is utilized by the building sector - mainly for heating of buildings and water. Different methods are used for the reduction of this energy - new thermo-isolating materials in the new building process, treating of the already existing buildings with thermo-isolating coverings, new aluminium and PVC frames for the windows, application of different solar equipment. At the same time the energy necessary for the heating of water for domestic usage increases permanently. Besides, the need for hot water is constant - every day, all the years. Here the possibilities for saving energy are more limited - limitation of the quantities of consumed hot water (but the statistics show just the opposite tendency), or recycling of the residual heat that is contained in the sewerage hot water, domestic and industrial. This solution is possible and technologically feasible through the usage of thermo-exchanging devices and thermo-pumps, and a process in which only the heat / thermal energy / of the sewerage water is accumulated, and then returned to the equipment for heating water. The heating module could be repaid for a period of 3.5 - 4 years as a result of the savings of thermal energy, which is economically very advantageous. And last but not least, the process has favourable ecological effect, following the world's latest tendencies. (author)

  12. Environmental assessment of domestic wood heating

    International Nuclear Information System (INIS)

    Labouze, E.; Le Guerin, Y.

    2009-01-01

    In France, more than 6 million families are concerned with the domestic use of wood energy. The wood energy plan of ADEME aims at encouraging the development of wood energy in three sectors: domestic, collective/tertiary, industrial. In that context, ADEME commissioned BIO Intelligence Service a life cycle assessment of collective and industrial heating in order to give objective environmental information and to analyse the strength and weakness of wood heating. Three scenarios were defined according to the origin of wood: firewood, granules and sawmill chips. The study also proposes a comparison to other heating systems: gas, fuel oil and electricity. The life cycle analysis applied to domestic heating consists in quantifying the environmental impacts of the whole linked steps: extraction of fuel, distribution, final use... Every system under study has been divided according to three main stages: - Extraction of raw materials; - Transport of fuels until the place of storage or distribution; - Use (combustion or upstream production of energy in the case of electricity). The environmental impacts are estimated with the following indicators: - Non renewable primary energy balance sheet; - Global warming potential; - Air acidification potential; - Eutrophication potential; - Emissions of toxic metals in air and in soils. The results show that wood heating have the best energy and global warming balance sheets. For air acidification, the combustion stage is pre-dominant regardless of the energy resource. This is mainly due to nitrogen and sulphur oxides airborne emissions. For wood heating, preparation requires fuel consumption which also contributes significantly to nitrogen oxides emissions. The comparison with conventional energy shows that the wood scenarios are well positioned in relation to fuel and electricity for this indicator. Gas appears to be the best heating option for this indicator. The contribution eutrophication is also due to nitrogen oxides airborne

  13. Multilevel Flow Modeling of Domestic Heating Systems

    DEFF Research Database (Denmark)

    Hu, Junjie; Lind, Morten; You, Shi

    2012-01-01

    the operation on fault analysis and control. A significant improvement of the MFM methodology has been recently proposed, where the “role” concept was introduced to enable the representation of structural entities and the conveyance of important information for building up knowledge bases, with the purpose...... i.e. supplying and transferring thermal energy, it is off interest to use MFM to investigate similarities and differences between different implementations. In this paper, three typical domestic European heating systems, which differ from each other in the number of temperature sensors and auxiliary...

  14. Integration of space heating and hot water supply in low temperature district heating

    DEFF Research Database (Denmark)

    Elmegaard, Brian; Ommen, Torben Schmidt; Markussen, Michael

    2016-01-01

    District heating may supply many consumers efficiently, but the heat loss from the pipes to the ground is a challenge. The heat loss may be lowered by decreasing the network temperatures for which reason low temperature networks are proposed for future district heating. The heating demand...... of the consumers involves both domestic hot water and space heating. Space heating may be provided at low temperature in low energy buildings. Domestic hot water, however, needs sufficient temperatures to avoid growth of legionella. If the network temperature is below the demand temperature, supplementary heating...... is required by the consumer. We study conventional district heating at different temperatures and compare the energy and exergetic efficiency and annual heating cost to solutions that utilize electricity for supplementary heating of domestic hot water in low temperature district heating. This includes direct...

  15. 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

  16. Solar heating, cooling and domestic hot water system installed at Columbia Gas System Service Corporation, Columbus, Ohio

    Science.gov (United States)

    1980-01-01

    The solar energy system installed in the building has 2,978 sq ft of single axis tracking, concentrating collectors and provides solar energy for space heating, space cooling and domestic hot water. A 1,200,000 Btu/hour water tube gas boiler provides hot water for space heating. Space cooling is provided by a 100 ton hot water fired absorption chiller. Domestic hot water heating is provided by a 50 gallon natural gas domestic storage water heater. Extracts from the site files, specification references, drawings, installation, operation and maintenance instructions are included.

  17. A winter survey of domestic heating among elderly patients.

    Science.gov (United States)

    Morgan, R; Blair, A; King, D

    1996-02-01

    Elderly people have a greater need for domestic heating given the time they spend at home and the decline in the body thermoregulation that occurs with ageing. The use of domestic heating by 200 mentally competent newly admitted elderly in patients was evaluated by means of a questionnaire survey. Most patients (69%) were aware of the addition of value added tax (VAT) to their fuel bill and 31% said they had reduced the amount of heating they use because of this. A third of patients (29.5%) said they had difficulty keeping warm prior to this admission. The majority of patients said they could not manage to keep warm in the winter without financial hardship. In addition, 29% said they had reduced the amount spent on food in order to pay for fuel bills. This study suggests that cold may contribute to hospital admissions in elderly patients. This should have implications for government spending and taxation policy on domestic heating.

  18. Solar heating and domestic hot water system installed at Kansas City, Fire Stations, Kansas City, Missouri

    Science.gov (United States)

    1980-01-01

    The solar system was designed to provide 47 percent of the space heating, 8,800 square feet area and 75 percent of the domestic hot water (DHW) load. The solar system consists of 2,808 square feet of Solaron, model 2001, air, flat plate collector subsystem, a concrete box storage subsystem which contains 1,428 cubic feet of 0.5 inch diameter pebbles weighing 71.5 tons, a DHW preheat tank, blowers, pumps, heat exchangers, air ducting, controls and associated plumbing. Two 120 gallon electric DHW heaters supply domestic hot water which is preheated by the solar system. Auxiliary space heating is provided by three electric heat pumps with electric resistance heaters and four 30 kilowatt electric unit heaters. There are six modes of system operation.

  19. Solar heating and domestic hot water system installed at Kansas City, Fire Stations, Kansas City, Missouri

    Science.gov (United States)

    1980-07-01

    The solar system was designed to provide 47 percent of the space heating, 8,800 square feet area and 75 percent of the domestic hot water (DHW) load. The solar system consists of 2,808 square feet of Solaron, model 2001, air, flat plate collector subsystem, a concrete box storage subsystem which contains 1,428 cubic feet of 0.5 inch diameter pebbles weighing 71.5 tons, a DHW preheat tank, blowers, pumps, heat exchangers, air ducting, controls and associated plumbing. Two 120 gallon electric DHW heaters supply domestic hot water which is preheated by the solar system. Auxiliary space heating is provided by three electric heat pumps with electric resistance heaters and four 30 kilowatt electric unit heaters. There are six modes of system operation.

  20. Aggregated Control of Domestic Heat Pumps

    DEFF Research Database (Denmark)

    Nielsen, Kirsten M.; Andersen, Palle; Pedersen, Tom S.

    2013-01-01

    A challenge in Denmark in the near future is to balance the electrical grid due to a large increase in the renewable energy production mainly from wind turbines. In this work an aggregated control system using heat pumps in single family houses to help balancing the grid is investigated....... The control system is able to adjust the consumptions of the heat pump without affecting the comfort in the houses and uses this ability to shift the total consumption to hours with high wind energy production....

  1. Modelling and multi-scenario analysis for electric heat tracing system combined with low temperature district heating for domestic hot water supply

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2016-01-01

    Low temperature district heating (LTDH) is a cost-efficient way of supplying space heating and domestic hot water (DHW) for buildings in urban areas. However, there is concern that the potential hygiene problems (Legionella) might occur if LTDH is implemented, especially for large buildings...... performance on heat loss saving, and it also gave benefits to district heating network by sharing part of the heating load....

  2. Contribution of domestic heating systems to smart grid control

    DEFF Research Database (Denmark)

    Tahersima, Fatemeh; Stoustrup, Jakob; Meybodi, Soroush Afkhami

    2011-01-01

    How and to what extent, domestic heating systems can be helpful in regaining power balance in a smart grid, is the question to be answered in this paper. Our case study is an under-floor heating system supplied with a geothermal heat pump which is driven by electrical power from the grid. The idea...... is to deviate power consumption of the heat pump from its optimal value, in order to compensate power imbalances in the grid. Heating systems could be forced to consume energy, i.e. storing it in heat buffers when there is a power surplus in the grid; and be prevented from using power, in case of power shortage....... We have investigated how much power imbalance could be compensated, provided that a certain, yet user adjustable, level of residents' thermal comfort is satisfied. It is shown that the large heat capacity of the concrete floor alleviates undesired temperature fluctuations. Therefore, incorporating...

  3. Microeconomics and the demand for space heating

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, D.J.

    1977-12-01

    The techniques of economic utility theory are combined with the technical equations for heat loss from a dwelling to give insight into the variation of consumer demand for space heating. A theoretical relationship is established between the performance of the occupied dwelling as the external temperature falls and the short-run income elasticity of energy demand. The analysis is applied to studies of UK heating practice in the 1950s and the implied indifference map for thermal comfort deduced. This indifference map is found to show a considerable economic propensity to absorb some of the potential savings from energy conservation measurements in higher internal temperatures. The effect found is sufficiently large to have consequences for future energy planning if it were still present in the UK domestic sector. The analysis highlights a number of points that should aid the interpretation of field experiments on domestic energy consumption. In particular, it is shown that unless great care is taken to separate out the technical and economic origins of internal temperature variation, the results of field studies on the effectiveness of conservation techniques may only be of shortlived value.

  4. Simulation of hybrid ground-coupled heat pump with domestic hot water heating systems using HVACSIM+

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Ping; Yang, Hongxing [Department of Building Services Engineering, The Hong Kong Polytechnic University, Hong Kong (China); Spitler, Jeffrey D. [School of Mechanical Engineering, Oklahoma State University (United States); Fang, Zhaohong [Ground Source Heat Pump Research Center, Shandong University of Architecture and Engineering, Jinan (China)

    2008-07-01

    A hybrid ground-coupled heat pump (HGCHP) with domestic hot water (DHW) supply system has been proposed in this paper for space cooling/heating and DHW supply for residential buildings in hot-climate areas. A simulation model for this hybrid system is established within the HVACSIM+ environment. A sample system, applied for a small residential apartment located in Hong Kong, is hourly simulated in a typical meteorological year. The conventional GCHP system and an electric heater for DHW supply are also modeled and simulated on an hourly basis within the HVACSIM+ for comparison purpose. The results obtained from this case study show that the HGCHP system can effectively alleviate the imbalanced loads of the ground heat exchanger (GHE) and can offer almost 95% DHW demand. The energy saving for DHW heating is about 70% compared with an electric heater. This proposed scheme, i.e. the HGCHP with DHW supply, is suitable to residential buildings in hot-climate areas, such as in Hong Kong. (author)

  5. Achieving low return temperature for domestic hot water preparation by ultra-low-temperature district heating

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Svendsen, Svend

    2017-01-01

    District heating (DH) is a cost-effective method of heat supply, especially to area with high heat density. Ultra-low-temperature district heating (ULTDH) is defined with supply temperature at 35-45 degrees C. It aims at making utmost use of the available low-temperature energy sources. In order...... to achieve high efficiency of the ULTDH system, the return temperature should be as low as possible. For the energy-efficient buildings in the future, it is feasible to use ULTDH to cover the space heating demand. However, considering the comfort and hygiene requirements of domestic hot water (DHW...... lower return temperature and higher efficiency for DHW supply, an innovative substation was devised, which replaced the bypass with an instantaneous heat exchanger and a micro electric storage tank. The energy performance of the proposed substation and the resulting benefits for the DH system...

  6. Environmental assessment of wood domestic heating. Synthetic report

    International Nuclear Information System (INIS)

    2005-12-01

    This report proposes a synthesis of the results of an environmental assessment of wood domestic heating. This study is based on a life cycle analysis which quantifies the impacts on the environment of all the related activities: fuel extraction, retailing, final use, and so on. Environmental impacts are assessed by means of different indicators: energetic assessment, greenhouse effect assessment, air pollution (acidification), water pollution (eutrophication), toxic material emissions in air and into the soils. Wood is compared to other heating sources (gas, fuel, electricity). Ways to improve this environmental assessment are discussed for the different types of wood (logs, pellets)

  7. Retrofitting Combined Space and Water Heating Systems: Laboratory Tests

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, B.; Bohac, D.; Huelman, P.; Olson, R.; Hewitt, M.

    2012-10-01

    Better insulated and tighter homes can often use a single heating plant for both space and domestic water heating. These systems, called dual integrated appliances (DIA) or combination systems, can operate at high efficiency and eliminate combustion safety issues associated by using a condensing, sealed combustion heating plant. Funds were received to install 400 DIAs in Minnesota low-income homes. The NorthernSTAR DIA laboratory was created to identify proper system components, designs, operating parameters, and installation procedures to assure high efficiency of field installed systems. Tests verified that heating loads up to 57,000 Btu/hr can be achieved with acceptable return water temperatures and supply air temperatures.

  8. Retrofitting Combined Space and Water Heating Systems. Laboratory Tests

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, B. [NorthernStar Building America Partnership, St. Paul, MN (United States); Bohac, D. [NorthernStar Building America Partnership, St. Paul, MN (United States); Huelman, P. [NorthernStar Building America Partnership, St. Paul, MN (United States); Olsen, R. [NorthernStar Building America Partnership, St. Paul, MN (United States); Hewett, M. [NorthernStar Building America Partnership, St. Paul, MN (United States)

    2012-10-01

    Better insulated and tighter homes can often use a single heating plant for both space and domestic water heating. These systems, called dual integrated appliances (DIA) or combination systems, can operate at high efficiency and eliminate combustion safety issues associated by using a condensing, sealed combustion heating plant. Funds were received to install 400 DIAs in Minnesota low-income homes. The NorthernSTAR DIA laboratory was created to identify proper system components, designs, operating parameters, and installation procedures to assure high efficiency of field installed systems. Tests verified that heating loads up to 57,000 Btu/hr can be achieved with acceptable return water temperatures and supply air temperatures.

  9. Domestic Hot Water Production with Ground Source Heat Pump in Apartment Buildings

    Directory of Open Access Journals (Sweden)

    Jukka Yrjölä

    2015-08-01

    Full Text Available Producing domestic hot water (DHW with a ground source heat pump (GSHP is challenging due to the high temperature (HT of DHW. There are many studies proving the better performance of cascade heat pumps compared to single-stage heat pumps when the difference between the condensing and the evaporation temperature is large. In this system approach study, different GSHP arrangements are described and computationally compared. A two-stage heat pump arrangement is introduced in which water tanks of the heating system are utilized for warming up the DHW in two stages. It is shown that the electricity consumption with this two-stage system is approximately 31% less than with the single-stage heat pump and 12% less than with the cascade system. Further, both low temperature (LT and HT heat pumps can run alone, which is not common in cascade or other two-stage heat pumps. This is advantageous because the high loads of the space heating and DHW production are not simultaneous. Proper insulation of the DHW and recirculation pipe network is essential, and drying towel rails or other heating coils should be avoided when aiming for a high efficiency. The refrigerants in the calculations are R407C for the LT heat pump and R134a for the HT heat pump. Investment costs are excluded from calculations.

  10. Spatial Resilience of Outdoor Domestic Space in Mozambique

    Directory of Open Access Journals (Sweden)

    Céline Felicio Veríssimo

    2012-07-01

    Full Text Available Historically, the people of Mozambique have faced oppression and social spatial segregation and responded in a way that has reinforced rather than dismantled their traditional values. Since pre-colonial times, the population’s strategy for escaping from environmental and foreign political disruption has been to reinvent tradition, based on the principles of resilience, resistance and self-reliance. The development of decentralised human settlements, involving the appropriation of land for domestic space and the self-organisation of neighbourhoods, were strategies to protect communities from adversity and secure collective self-reliance. Following Mozambique’s conversion to globalization, the post-colonial ‘cement city’ is now the core of neo-liberalism, as a node of the global economy, where foreign donors and international market economy control national political economy, exacerbating the premise of the negation of self-sufficiency that continues to evolve resiliently at its margins. The adoption of a neo-liberal model of development during the 1990s, completely bypasses the realities of Mozambican society. This paper argues that the strategy of self-production of space regarding the household/Outdoor Domestic Space unit, which existed previously as a resistance strategy, first of all against colonialism and secondly, against the statist definition of socialism, thirdly, has become a successful strategy for survival, as the building block of the decentralised Agrocity, in the face of a global economy which totally neglects both the people and the land. Outdoor Domestic Space is a multifaceted space that refers to the external space surrounding the built house and which, in the case of Mozambique, is where daily life takes place, involving strong social, ecological and productive functions. Under successive periods of political economy oppression and environmental adversity, the Outdoor Domestic Space has been adapted and refined to

  11. Low Temperature District Heating Consumer Unit with Micro Heat Pump for Domestic Hot Water Preparation

    DEFF Research Database (Denmark)

    Zvingilaite, Erika; Ommen, Torben Schmidt; Elmegaard, Brian

    2012-01-01

    In this paper we present and analyse the feasibility of a district heating (DH) consumer unit with micro heat pump for domestic hot water (DHW) preparation in a low temperature (40 °C) DH network. We propose a micro booster heat pump of high efficiency (COP equal to 5,3) in a consumer DH unit...... in order to boost the temperature of the district heating water for heating the DHW. The paper presents the main designs of the suggested system and different alternative micro booster heat pump concepts. Energy efficiency and thermodynamic performance of these concepts are calculated and compared....... The results show that the proposed system has the highest efficiency. Furthermore, we compare thermodynamic and economic performance of the suggested heat pump-based concept with different solutions, using electric water heater. The micro booster heat pump system has the highest annualised investment (390 EUR...

  12. Ambient air pollution associated to domestic wood burning heating systems

    International Nuclear Information System (INIS)

    Friboulet, I.; Durif, M.; Malherbe, L.

    2009-01-01

    Main publications are considering effects of wood burning appliances on indoor air quality, which is a major issue in some countries. But impacts on ambient air, close environment and human exposure are rather poorly characterised so far. Besides, woods burning for domestic purpose may develop in the next years while promoting bio fuels. The aim of the ongoing study is to assess in which conditions associated air pollution and population exposure could be significant, this poster shows preliminary results of the impact of a village of 98 houses equipped with a wood burning heating system. (N.C.)

  13. Domestic heat pumps in the UK. User behaviour, satisfaction and performance

    Energy Technology Data Exchange (ETDEWEB)

    Caird, S.; Roy, R.; Potter, S. [Design Innovation Group, Dept. Design, Development, Environment and Materials, Faculty of Mathematics, Computing and Technology, The Open University, Milton Keynes, MK7 6AA (United Kingdom)

    2012-08-15

    Consumer adoption of microgeneration technologies is part of the UK strategy to reduce carbon emissions from buildings. Domestic heat pumps are viewed as a potentially important carbon saving technology, given the ongoing decarbonisation of the electricity supply system. To address the lack of independent evaluation of heat pump performance, the Energy Saving Trust undertook the UK's first large-scale heat pump field trial, which monitored 83 systems in real installations. As part of the trial, the Open University studied the consumers' experience of using a domestic heat pump. An in-depth user survey investigated the characteristics, behaviour, and satisfactions of private householders and social housing residents using ground source and air source heat pumps for space and/or water heating, and examined the influence of user-related factors on measured heat pump system efficiency. The surveys found that most users were satisfied with the reliability, heating, hot water, warmth and comfort provided by their system. Analysis of user characteristics showed that higher system efficiencies were associated with greater user understanding of their heat pump system, and more continuous heat pump operation, although larger samples are needed for robust statistical confirmation. The analysis also found that the more efficient systems in the sample were more frequently located in the private dwellings than at the social housing sites and this difference was significant. This is explained by the interaction between differences in the systems, dwellings and users at the private and social housing sites. The implications for heat pump research, practice and policy are discussed.

  14. Dynamic Allocation of a Domestic Heating Task to Gas-Based and Heatpump-Based Heating Agents

    NARCIS (Netherlands)

    Treur, J.

    2013-01-01

    In this paper a multi-agent model for a domestic heating task is introduced and analysed. The model includes two alternative heating agents (for gas-based heating and for heatpump-based heating), and a third allocation agent which determines the most economic allocation of the heating task to these

  15. Heat transfer capability analysis of heat pipe for space reactor

    International Nuclear Information System (INIS)

    Li Huaqi; Jiang Xinbiao; Chen Lixin; Yang Ning; Hu Pan; Ma Tengyue; Zhang Liang

    2015-01-01

    To insure the safety of space reactor power system with no single point failures, the reactor heat pipes must work below its heat transfer limits, thus when some pipes fail, the reactor could still be adequately cooled by neighbor heat pipes. Methods to analyze the reactor heat pipe's heat transfer limits were presented, and that for the prevailing capillary limit analysis was improved. The calculation was made on the lithium heat pipe in core of heat pipes segmented thermoelectric module converter (HP-STMC) space reactor power system (SRPS), potassium heat pipe as radiator of HP-STMC SRPS, and sodium heat pipe in core of scalable AMTEC integrated reactor space power system (SAIRS). It is shown that the prevailing capillary limits of the reactor lithium heat pipe and sodium heat pipe is 25.21 kW and 14.69 kW, providing a design margin >19.4% and >23.6%, respectively. The sonic limit of the reactor radiator potassium heat pipe is 7.88 kW, providing a design margin >43.2%. As the result of calculation, it is concluded that the main heat transfer limit of HP-STMC SRPS lithium heat pipe and SARIS sodium heat pipe is prevailing capillary limit, but the sonic limit for HP-STMC SRPS radiator potassium heat pipe. (authors)

  16. Technical, economic and environmental investigation of using district heating to prepare domestic hot water in Chinese multi-storey buildings

    DEFF Research Database (Denmark)

    Zhang, Lipeng; Xia, Jianjun; Thorsen, Jan Eric

    2016-01-01

    The development of DH (District Heating) is an environmentally friendly and energy-efficient strategy in China. Currently, the vast majority of DH systems are SH (Space Heating) only and do not provide DHW (Domestic Hot Water). DHW is mainly produced by individual water heaters due to the cost......-effective issues of the centralized DHW systems. From the perspective of long-term development, DHW produced via DH systems would be more sustainable because DH is an important precondition for an environmental safe use of domestic waste fuels. This paper presents an approach that uses flat stations meanwhile...

  17. Projecting Homes: Domestic Spaces in Three Filipino Films

    Directory of Open Access Journals (Sweden)

    Tito R. Quiling Jr.

    2013-12-01

    Full Text Available The house is a fundamental space for a character’s consciousness, and this structure is a familiar image in Filipino f ilms. This particular space as a setting in which the narrative and the characters are able to move in, is essential. This paper analyzes the influence of domestic spaces and the characteristics of home, which correspond to the characters’ consciousness and the narrative. These are presented in the selected films: Oro, Plata, Mata (1982 by Peque Gallaga, “Hellow, Soldier,” the second episode in Lino Brocka’s Tatlo, Dalawa, Isa (1975, and Kisapmata (1981 by Mike De Leon. The method for assessment consists of three parts: (1 the background in which the films are set, (2 the influence of the house using Gaston Bachelard’s notion of the house in The Poetics of Space (1994 as a framework, (3 and the behavior of the characters as portrayed in the films. The significance of domestic spaces to a character’s experience is illustrated in the selected texts.

  18. Farm effluent plant produces gas for domestic heat and power

    Energy Technology Data Exchange (ETDEWEB)

    1963-01-01

    A plant for treating farm waste waters, developed by Wright Rain Ltd. and based on a prototype plant invented by J. Fry which has been in continuous use for 5 years on a pig farm at Rietvlei, Johannesburg, is described. Manure is pumped into one end of the digestion tank about one-third of the way up the tank, and anaerobic decomposition occurs at a controlled temperature (optimum 35/sup 0/C); the gas rises to the top and is collected in gas holders to be utilized for domestic heat and power, while an outlet near the bottom of the tank allows decomposed matter to be drawn off for spreading. Results with pig manure suggest that a digestion tank should be planned for a 60-day cycle. Cow and pig manure can be digested without difficulty, but it would be necessary to add water to chicken manure for successful digestion.

  19. Heat Conduction of Air in Nano Spacing

    Directory of Open Access Journals (Sweden)

    Zhang Yao-Zhong

    2009-01-01

    Full Text Available Abstract The scale effect of heat conduction of air in nano spacing (NS is very important for nanodevices to improve their life and efficiency. By constructing a special technique, the changes of heat conduction of air were studied by means of measuring the heat conduction with heat conduction instrument in NS between the hot plate and the cooling plate. Carbon nanotubes were used to produce the nano spacing. The results show that when the spacing is small down to nanometer scale, heat conduction plays a prominent role in NS. It was found that the thickness of air is a non-linear parameter for demarcating the heat conduction of air in NS and the rate of heat conduction in unit area could be regard as a typical parameter for the heat conduction characterization at nanometer scale.

  20. Solar heating, cooling, and domestic hot water system installed at Kaw Valley State Bank and Trust Company, Topeka, Kansas

    Science.gov (United States)

    1980-01-01

    The building has approximately 5600 square feet of conditioned space. Solar energy was used for space heating, space cooling, and preheating domestic hot water (DHW). The solar energy system had an array of evacuated tube-type collectors with an area of 1068 square feet. A 50/50 solution of ethylene glycol and water was the transfer medium that delivered solar energy to a tube-in-shell heat exchanger that in turn delivered solar heated water to a 1100 gallon pressurized hot water storage tank. When solar energy was insufficient to satisfy the space heating and/or cooling demand, a natural gas-fired boiler provided auxiliary energy to the fan coil loops and/or the absorption chillers. Extracts from the site files, specification references, drawings, and installation, operation and maintenance instructions are presented.

  1. Solar Energy for Space Heating & Hot Water.

    Science.gov (United States)

    Energy Research and Development Administration, Washington, DC. Div. of Solar Energy.

    This pamphlet reviews the direct transfer of solar energy into heat, particularly for the purpose of providing space and hot water heating needs. Owners of buildings and homes are provided with a basic understanding of solar heating and hot water systems: what they are, how they perform, the energy savings possible, and the cost factors involved.…

  2. A Direct Heat Exchanger Unit used for Domestic Hot Water Supply in a Single-family House Supplied by Low Energy District Heating

    DEFF Research Database (Denmark)

    Brand, Marek; Thorsen, Jan Eric; Svendsen, Svend

    2010-01-01

    The increasing number of new and renovated buildings with reduced heating requirements will soon make traditional District Heating (DH) systems uneconomic. To keep DH competitive in the future, the heat loss in DH networks needs to be reduced. One option is to reduce the supply temperature of DH...... as much as possible. This requires a review of the behaviour of the whole domestic hot water (DHW) supply system with focus on the user comfort and overall costs. This paper describes some practical approaches to the implementation of this Low Energy District Heating (LEDH) concept. It reports...... on the testing of the dynamic behaviour of an Instantaneous Heat Exchanger Unit(IHEU) designed for DHW heating and space heating in detached family houses supplied by LEDH ensuring an entry-to-substation temperature of 51 °C. We measured the time it takes for the IHEU to produce DHW with a temperature of 42 °C...

  3. Heat pump system with selective space cooling

    Science.gov (United States)

    Pendergrass, J.C.

    1997-05-13

    A reversible heat pump provides multiple heating and cooling modes and includes a compressor, an evaporator and heat exchanger all interconnected and charged with refrigerant fluid. The heat exchanger includes tanks connected in series to the water supply and a condenser feed line with heat transfer sections connected in counterflow relationship. The heat pump has an accumulator and suction line for the refrigerant fluid upstream of the compressor. Sub-cool transfer tubes associated with the accumulator/suction line reclaim a portion of the heat from the heat exchanger. A reversing valve switches between heating/cooling modes. A first bypass is operative to direct the refrigerant fluid around the sub-cool transfer tubes in the space cooling only mode and during which an expansion valve is utilized upstream of the evaporator/indoor coil. A second bypass is provided around the expansion valve. A programmable microprocessor activates the first bypass in the cooling only mode and deactivates the second bypass, and vice-versa in the multiple heating modes for said heat exchanger. In the heating modes, the evaporator may include an auxiliary outdoor coil for direct supplemental heat dissipation into ambient air. In the multiple heating modes, the condensed refrigerant fluid is regulated by a flow control valve. 4 figs.

  4. Determinants of residential space heating expenditures in Great Britain

    Energy Technology Data Exchange (ETDEWEB)

    Meier, Helena [Department of Economics, University of Hamburg, Von Melle Park 5, 20146 Hamburg (Germany); Rehdanz, Katrin [Department of Economics, University of Kiel, Olshausenstrasse 40, 24118 Kiel (Germany)

    2010-09-15

    In Great Britain, several policy measures have been implemented in order to increase energy efficiency and reduce carbon emissions. In the domestic sector, this could, for example, be achieved by improving space heating efficiency and thus decreasing heating expenditure. However, in order to efficiently design and implement such policy measures, a better understanding of the determinants affecting heating expenditure is needed. In this paper we examine the following determinants: socio-economic factors, building characteristics, heating technologies and weather conditions. In contrast to most other studies we use panel data to investigate household demand for heating in Great Britain. Our data sample is the result of an annual set of interviews with more than 5000 households, starting in 1991 and ending in 2005. The sample represents a total of 64,000 observations over the fifteen-year period. Our aim is to derive price and income elasticities both for Britain as a whole and for different types of household. Our results suggest that differences exist between owner-occupied and renter households. These households react differently to changes in income and prices. Our results also imply that a number of socio-economic criteria have a significant influence on heating expenditure, independently of the fuel used for heating. Understanding the impacts of different factors on heating expenditure and impact differences between types of household is helpful in designing target-oriented policy measures. (author)

  5. Modelling domestic stock energy use and heat-related health risk : a GIS-based bottom-up modelling approach

    Energy Technology Data Exchange (ETDEWEB)

    Mavrogianni, A.; Davies, M. [Univ. College London, London (United Kingdom). Bartlett School of Graduate Studies; Chalabi, Z.; Wilkinson, P. [London School of Hygiene and Tropical Medecine, London (United Kingdom); Kolokotroni, M. [Brunel Univ., London (United Kingdom). School of Engineering Design

    2009-07-01

    Approximately 8 per cent of the carbon dioxide (CO{sub 2}) emissions produced in the United Kingdom are produced in London, one of the fastest growing cities worldwide. Based on the projected rates of population and economic growth, a 15 per cent increase of emissions is predicted. In addition to the national target to cut emissions by 80 per cent by 2050, the Mayor of London Climate Change Action Plan set a target to reduce London's CO{sub 2} emissions by 60 per cent by 2025. Significant carbon savings can be achieved in the building sector, particularly since 38 per cent of the total delivered energy in London is associated with domestic energy use. This paper demonstrated a systematic approach towards exploring the impact of urban built form and the combined effect of climate change and the urban heat island (UHI) phenomenon on the levels of domestic energy consumption and heat-related health risk in London. It presented work in progress on the development of a GIS-based energy consumption model and heat vulnerability index of the Greater London Area domestic stock. Comparison of the model output for 10 case study areas with topdown energy statistics revealed that the model successfully ranks areas based on their domestic space heating demand. The health module can be used to determine environments prone to higher risk of heat stress by investigating urban texture factors. A newly developed epidemiological model will be feed into the health module to examine the influence on risk of heat-related mortality of local urban built form characteristics. The epidemiological model is based on multi-variable analysis of deaths during heat wave and non-heat wave days. 29 refs., 1 tab., 7 figs.

  6. Combined Active and Passive Solar Space Heating and Solar Hot Water Systems for an Elementary School in Boise, Idaho.

    Science.gov (United States)

    Smull, Neil A.; Armstrong, Gerald L.

    1979-01-01

    Amity Elementary School in Boise, Idaho, features a solar space heating and domestic hot water system along with an earth covering to accommodate the passive aspects of energy conservation. (Author/MLF)

  7. Measure Guideline: Combined Space and Water Heating Installation and Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, B. [Univ. of Minnesota, St. Paul, MN (United States). NorthernSTAR Building America Partnership; Bohac, D. [Univ. of Minnesota, St. Paul, MN (United States). NorthernSTAR Building America Partnership; Huelman, P. [Univ. of Minnesota, St. Paul, MN (United States). NorthernSTAR Building America Partnership

    2017-03-03

    Combined space and water heater (combi or combo) systems are defined by their dual functionality. Combi systems provide both space heating and water heating capabilities with a single heat source. This guideline will focus on the installation and operation of residential systems with forced air heating and domestic hot water (DHW) functionality. Past NorthernSTAR research has used a combi system to replace a natural gas forced air distribution system furnace and tank type water heater (Schoenbauer et al. 2012; Schoenbauer, Bohac, and McAlpine 2014). The combi systems consisted of a water heater or boiler heating plant teamed with a hydronic air handler that included an air handler, water coil, and water pump to circulate water between the heating plant and coil. The combi water heater or boiler had a separate circuit for DHW. Past projects focused on laboratory testing, field characterization, and control optimization of combi systems. Laboratory testing was done to fully characterize and test combi system components; field testing was completed to characterize the installed performance of combi systems; and control methodologies were analyzed to understand the potential of controls to simplify installation and design and to improve system efficiency and occupant comfort. This past work was relied upon on to create this measure guideline.

  8. Measure Guideline: Combined Space and Water Heating Installation and Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, B. [NorthernSTAR Building America Partnership, St. Paul, MN (United States); Bohac, D. [NorthernSTAR Building America Partnership, St. Paul, MN (United States); Huelman, P. [NorthernSTAR Building America Partnership, St. Paul, MN (United States)

    2017-03-01

    Combined space and water heater (combi or combo) systems are defined by their dual functionality. Combi systems provide both space heating and water heating capabilities with a single heat source. This guideline will focus on the installation and operation of residential systems with forced air heating and domestic hot water (DHW) functionality. Past NorthernSTAR research has used a combi system to replace a natural gas forced air distribution system furnace and tank type water heater (Schoenbauer et al. 2012; Schoenbauer, Bohac, and McAlpine 2014). The combi systems consisted of a water heater or boiler heating plant teamed with a hydronic air handler that included an air handler, water coil, and water pump to circulate water between the heating plant and coil. The combi water heater or boiler had a separate circuit for DHW. Past projects focused on laboratory testing, field characterization, and control optimization of combi systems. Laboratory testing was done to fully characterize and test combi system components; field testing was completed to characterize the installed performance of combi systems; and control methodologies were analyzed to understand the potential of controls to simplify installation and design and to improve system efficiency and occupant comfort. This past work was relied upon on to create this measure guideline.

  9. The relationship between domestic space and gender identity: Some signs of emergence of alternative domestic femininity and masculinity

    Directory of Open Access Journals (Sweden)

    Cătălina-Ionela Rezeanu

    2015-12-01

    Full Text Available The premise of this article is that, by introducing domestic space in the analysis of gender identity, one might gain a more nuanced understanding of how gender and power are co-constitutive. The research question is what one could learn from the conclusions of recent studies about the relationship between gender identity and domestic space, by analyzing it as a way of “doing and undoing gender” through spatial practices. We conducted an interpretive synthesis, focusing on 20 articles published in the last ten years on the topics of domestic space, masculinity, and femininity. We show the traditional normative model of gender identity is still strong, but there are some signs, of the emergence of alternative domestic masculinity and femininity, based on the tendency to reconsider the value of domesticity, and to transgress traditional gender oppositions (mind and body, rational and emotional, public and private, work and domesticity. We discuss the implications of the findings for understanding and refining the concepts of doing and doing gender, and gendered space.

  10. Anthropogenic heat flux estimation from space

    NARCIS (Netherlands)

    Chrysoulakis, Nektarios; Marconcini, Mattia; Gastellu-Etchegorry, Jean Philippe; Grimmond, C.S.B.; Feigenwinter, Christian; Lindberg, Fredrik; Frate, Del Fabio; Klostermann, Judith; Mitraka, Zina; Esch, Thomas; Landier, Lucas; Gabey, Andy; Parlow, Eberhard; Olofson, Frans

    2016-01-01

    H2020-Space project URBANFLUXES (URBan ANthrpogenic heat FLUX from Earth observation Satellites) investigates the potential of Copernicus Sentinels to retrieve anthropogenic heat flux, as a key component of the Urban Energy Budget (UEB). URBANFLUXES advances the current knowledge of the impacts

  11. ANthropogenic heat FLUX estimation from Space

    NARCIS (Netherlands)

    Chrysoulakis, Nektarios; Marconcini, Mattia; Gastellu-Etchegorry, Jean Philippe; Grimmong, C.S.B.; Feigenwinter, Christian; Lindberg, Fredrik; Frate, Del Fabio; Klostermann, Judith; Mi, Zina; Esch, Thomas; Landier, Lucas; Gabey, Andy; Parlow, Eberhard; Olofson, Frans

    2017-01-01

    The H2020-Space project URBANFLUXES (URBan ANthrpogenic heat FLUX from Earth observation Satellites) investigates the potential of Copernicus Sentinels to retrieve anthropogenic heat flux, as a key component of the Urban Energy Budget (UEB). URBANFLUXES advances the current knowledge of the

  12. Thulium heat sources for space power applications

    International Nuclear Information System (INIS)

    Alderman, C.J.

    1992-05-01

    Reliable power supplies for use in transportation and remote systems will be an important part of space exploration terrestrial activities. A potential power source is available in the rare earth metal, thulium. Fuel sources can be produced by activating Tm-169 targets in the space station reactor. The resulting Tm-170 heat sources can be used in thermoelectric generators to power instrumentation and telecommunications located at remote sites such as weather stations. As the heat source in a dynamic Sterling or Brayton cycle system, the heat source can provide a lightweight power source for rovers or other terrestrial transportation systems

  13. Crawl space assisted heat pump. [using stored ground heat

    Science.gov (United States)

    Ternes, M. P.

    1980-01-01

    A variety of experiments and simulations, currently being designed or underway, to determine the feasibility of conditioning the source air of an air to air heat pump using stored ground heat or cool to produce higher seasonal COP's and net energy savings are discussed. The ground would condition ambient air as it is drawn through the crawl space of a house. Tests designed to evaluate the feasibility of the concept, to determine the amount of heat or cool available from the ground, to study the effect of the system on the heating and cooling loads of the house, to study possible mechanisms which could enhance heat flow through the ground, and to determine if diurnal temperature swings are necessary to achieve successful system performance are described.

  14. Solar air heating system for combined DHW and space heating

    Energy Technology Data Exchange (ETDEWEB)

    Oestergaard Jensen, S.; Bosanac, M.

    2002-12-01

    The project deals with the development and testing of a simple system for utilization of the summer excess heat from small solar air heating systems for preheating of fresh air. The principle of the system is to lead the heated air down around a domestic hot water tank letting the surface of the tank act as heat exchanger between the air and the water. In order to increase the heat transfer, coefficient fins into the air stream were mounted on the tank. A complete system with 3 m{sup 2} solar air collector, ductworks and a 85 litre storage were set up and extensively monitored. The air stream through the system was created by a fan connected directly to one or two PV-panels leading to a solar radiation dependent flow rate without the use of any other control. Based on monitoring results the system was characterized and a TRNSYS model of the system was developed and calibrated/validated. The monitoring and the simulations with the TRNSYS model revealed several interesting things about the system. The monitoring revealed that the system is capable of bringing the temperature of the water in the storage above 60 deg. C at warm days with clear sky conditions. The storage is very stratified, which is beneficial as usable hot water temperatures rather quickly are obtained. The performance was highly dependent on the airflow rate through the system. It can be concluded that the investigated system will have a performance in the order of 500 kWh during the winter, spring and autumn months and around 250 kWh during the four summer months - or in total a yearly performance of 750 kWh/m{sup 2}. A small traditional solar heating system for preheating of domestic hot water would have a higher performance during the four summer months, but no performance during the rest of the year if the system is installed in a summer house, which only is occupied during the summer. The parametric analysis further indicates that it is possible to further optimise the system when the thermal

  15. Evaluations of different domestic hot water preparing methods with ultra-low-temperature district heating

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2016-01-01

    of Legionella in the DHW (domestic hot water) and assure the comfortable temperature, all substations were installed with supplementary heating devices. Detailed measurements were taken in the substations, including the electricity demand of the supplementary heating devices. To compare the energy and economic...

  16. Low-Cost Gas Heat Pump for Building Space Heating

    Energy Technology Data Exchange (ETDEWEB)

    Garrabrant, Michael [Stone Mountain Technologies, Inc., Johnson City, TN (United States); Keinath, Christopher [Stone Mountain Technologies, Inc., Johnson City, TN (United States)

    2016-10-11

    Gas-fired residential space heating in the U.S is predominantly supplied by furnaces and boilers. These technologies have been approaching their thermodynamic limit over the past 30 years and improvements for high efficiency units have approached a point of diminishing return. Electric heat pumps are growing in popularity but their heating performance at low ambient temperatures is poor. The development of a low-cost gas absorption heat pump would offer a significant improvement to current furnaces and boilers, and in heating dominated climate zones when compared to electric heat pumps. Gas absorption heat pumps (GAHP) exceed the traditional limit of thermal efficiency encountered by typical furnaces and boilers, and maintain high levels of performance at low ambient temperatures. The project team designed and demonstrated two low-cost packaged prototype GAHP space heating systems during the course of this investigation. Led by Stone Mountain Technologies Inc. (SMTI), with support from A.O. Smith, and the Gas Technology Institute (GTI), the cross-functional team completed research and development tasks including cycle modeling, 8× scaling of a compact solution pump, combustion system development, breadboard evaluation, fabrication of two packaged prototype units, third party testing of the first prototype, and the evaluation of cost and energy savings compared to high and minimum efficiency gas options. Over the course of the project and with the fabrication of two Alpha prototypes it was shown that this technology met or exceeded most of the stated project targets. At ambient temperatures of 47, 35, 17 and -13°F the prototypes achieved gas based coefficients of performance of 1.50, 1.44, 1.37, and 1.17, respectively. Both units operated with parasitic loads well below the 750 watt target with the second Alpha prototype operating 75-100 watts below the first Alpha prototype. Modulation of the units at 4:1 was achieved with the project goal of 2:1 modulation

  17. BIODIESEL BLENDS IN SPACE HEATING EQUIPMENT

    International Nuclear Information System (INIS)

    KRISHNA, C.R.

    2001-01-01

    Biodiesel is a diesel-like fuel that is derived from processing vegetable oils from various sources, such as soy oil, rapeseed or canola oil, and also waste vegetable oils resulting from cooking use. Brookhaven National laboratory initiated an evaluation of the performance of blends of biodiesel and home heating oil in space heating applications under the sponsorship of the Department of Energy (DOE) through the National Renewable Energy Laboratory (NREL). This report is a result of this work performed in the laboratory. A number of blends of varying amounts of a biodiesel in home heating fuel were tested in both a residential heating system and a commercial size boiler. The results demonstrate that blends of biodiesel and heating oil can be used with few or no modifications to the equipment or operating practices in space heating. The results also showed that there were environmental benefits from the biodiesel addition in terms of reductions in smoke and in Nitrogen Oxides (NOx). The latter result was particularly surprising and of course welcome, in view of the previous results in diesel engines where no changes had been seen. Residential size combustion equipment is presently not subject to NOx regulation. If reductions in NOx similar to those observed here hold up in larger size (commercial and industrial) boilers, a significant increase in the use of biodiesel-like fuel blends could become possible

  18. Emissions from three wood-fired domestic central heating boilers - heat load dependence

    International Nuclear Information System (INIS)

    Karlsson, M.L.

    1992-01-01

    The flue gases from three wood-fired domestic central heating boilers have been characterized. Measurements were made at three part loads; 3, 7 and 15 kW. Two of the boilers were modern multi-fuel boilers, with inverse firing and natural draught. The third boiler was a single-fuel wood boiler, with inverse firing and combustion air supply through a fan. All boilers were environmentally approved; the tar emissions were below 30 mg/MJ at nominal heat load. The following parameters were measured: - CO, CO 2 , NO x , total hydrocarbons (THC), - tar and particulates, - twelve volatile organic compounds (VOC). The limit value for tar emission was heavily exceeded for all three boilers at the part loads at which they were tested. For the two multi-fuel boilers the tar emissions decreased with increasing load level, while the opposite was found for the wood boiler with a fan. The NO x emissions varied between 20 and 120 mg/MJ. The multi-fuel boilers showed increasing NO x emissions with increasing heat load. The single-fuel wood boiler showed NO x emissions at about 60 mg/MJ, independent of load level. The CO and THC levels in general were high. The CO levels varied between 1000 and 2000 mg/MJ. While the THC levels varied between 300 and 4000 mg/MJ. Broadly speaking, the CO and THC levels decreased with increasing load levels for the multi-fuel boilers. For the single-fuel wood boiler the CO and THC levels were roughly the same at all load levels. Out of the twelve VOC compounds which were measured, the following could be detected and quantified. With FTIR analysis: Methane, ethylene, propene and acetylene. With GC analysis: Methanol, phenol and acetic acid. (1 ref., 31 figs., 7 tabs.)

  19. Sizing Combined Heat and Power Units and Domestic Building Energy Cost Optimisation

    OpenAIRE

    Dongmin Yu; Yuanzhu Meng; Gangui Yan; Gang Mu; Dezhi Li; Simon Le Blond

    2017-01-01

    Many combined heat and power (CHP) units have been installed in domestic buildings to increase energy efficiency and reduce energy costs. However, inappropriate sizing of a CHP may actually increase energy costs and reduce energy efficiency. Moreover, the high manufacturing cost of batteries makes batteries less affordable. Therefore, this paper will attempt to size the capacity of CHP and optimise daily energy costs for a domestic building with only CHP installed. In this paper, electricity ...

  20. Energy and environmental impact of domestic heating in Italy: Evaluation of national NOx emissions

    International Nuclear Information System (INIS)

    Aste, Niccolò; Adhikari, R.S.; Compostella, Junia; Pero, Claudio Del

    2013-01-01

    The domestic heating sector has a high potential in terms of energy savings and environmental impact. In the present study, an analysis has been carried out on the effect of domestic heating on natural gas (NG) consumption and pollutants emissions. In particular, among various emission pollutants, the nitrogen oxides (NO x ) emissions at national level were analyzed in detail. The work was carried out under a collaborative research project between the Italian Ministry of the Environment and Politecnico di Milano. For the assessment of the national NO x emissions due to residential heating, an inventory of the domestic boilers stock operating in Italy from 1999 to 2010 was made. As from a technological point of view, the precise data about the real composition of national domestic boilers stock were incomplete and not updated, a methodological procedure was developed in order to reconstruct the national domestic boilers stock based on the available technologies and thermal power. According to this scenario, the technological improvement of national boilers stock in the last decade was evaluated in terms of natural gas saving and reduced NO x emissions. Further some discussion has been made on the energy policies for the diffusion of more efficient boilers. - Highlights: ► First-of-its-kind study on the effect of domestic heating on NO x emissions. ► Inventory of national gas boiler population for domestic heating. ► Estimation of the main boilers typologies distribution on a national level. ► Technological improvement of thermal appliances and NO x emissions reduction.

  1. Potential for solar space heating in Scotland

    Energy Technology Data Exchange (ETDEWEB)

    Macgregor, A W.K.

    1980-07-01

    This paper investigates the relative effectiveness of passive-type solar-assisted space heating systems at various latitudes within the British Isles. A comparison is made of the useful solar gain of the same system linked to the same house at four different locations. Month-by-month energy balances indicate that the annual useful solar contribution at the highest latitude (Lerwick, 60 deg N) is about 35% higher than at the lowest latitude (Kew, 53 deg N). The main reason for this difference is the higher heating loads in the north, particularly outside the winter months. The estimated available irradiation on south-facing vertical surfaces was almost the same at all four locations. Previous work in the UK indicates that, contrary to the conclusions in this paper, more southerly latitudes were the most favorable for solar space heating. The reasons for the disparity are discussed. It is recommended that research and development of passive solar-assisted space heating systems should be most vigorously pursued in the more northerly latitudes of the British Isles, where both the potential benefit and the need are greatest.

  2. Solar space and water heating system at Stanford University Central Food Services Building. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1980-05-01

    This active hydronic domestic hot water and space heating system was 840 ft/sup 2/ of single-glazed, liquid, flat plate collectors and 1550 gal heat storage tanks. The following are discussed: energy conservation, design philosophy, operation, acceptance testing, performance data, collector selection, bidding, costs, economics, problems, and recommendations. An operation and maintenance manual and as-built drawings are included in appendices. (MHR)

  3. Residential CO{sub 2} heat pump system for combined space heating and hot water heating

    Energy Technology Data Exchange (ETDEWEB)

    Stene, Joern

    2004-02-01

    Carbon dioxide (CO{sub 2}, R-744) has been identified as a promising alternative to conventional working fluids in a number of applications due to its favourable environmental and thermophysical properties. Previous work on residential CO{sub 2} heat pumps has been dealing with systems for either space heating or hot water heating, and it was therefore considered interesting to carry out a theoretical and experimental study of residential CO{sub 2} heat pump systems for combined space heating and hot water heating - o-called integrated CO{sub 2} heat pump systems. The scope of this thesis is limited to brine-to-water and water-to-water heat pumps connected to low-temperature hydronic space heating systems. The main conclusions are: (1) Under certain conditions residential CO{sub 2} heat pump systems for combined space heating and hot water heating may achieve the same or higher seasonal performance factor (SPF) than the most energy efficient state-of-the-art brine-to-water heat pumps. (2) In contrary to conventional heat pump systems for combined space heating and DHW heating, the integrated CO{sub 2} heat pump system achieves the highest COP in the combined heating mode and the DHW heating mode, and the lowest COP in the space heating mode. Hence, the larger the annual DHW heating demand, the higher the SPF of the integrated CO{sub 2} heat pump system. (3) The lower the return temperature in the space heating system and the lower the DHW storage temperature, the higher the COP of the integrated CO{sub 2} heat pump. A low return temperature in the space heating system also results in a moderate DHW heating capacity ratio, which means that a relatively large part of the annual space heating demand can be covered by operation in the combined heating mode, where the COP is considerably higher than in the space heating mode. (4) During operation in the combined heating mode and the DHW heating mode, the COP of the integrated CO{sub 2} heat pump is heavily influenced by

  4. Modern Architecture, Spatial Precarity and the Female Body in the Domestic Spaces in Iran

    Directory of Open Access Journals (Sweden)

    Ladan Rahbari

    2016-12-01

    Full Text Available Iranian home is used as private, semi-private and public spaces. It has kept its traditional functions despite alterations in its structure and is a space for women to engage in caretaking and housekeeping activities. In this paper, I will discuss how modern architecture and its consequences such as the deletion of women-only spaces called Andarooni, has not acknowledged women's appropriation of the domestic space as it is not conformed to the Iranian lifestyle and patterns of social relations. Using ethnography, participant observation and informal conversations with Iranian women, I investigate the characteristics of the contemporary home which reveal how disappearing privateness of the domestic space has contributed to women's precarious bodily freedom in domestic spaces.

  5. Life cycle assessment of domestic heat pump hot water systems in Australia

    Directory of Open Access Journals (Sweden)

    Moore Andrew D.

    2017-01-01

    Full Text Available Water heating accounts for 23% of residential energy consumption in Australia, and, as over half is provided by electric water heaters, is a significant source of greenhouse gas emissions. Due to inclusion in rebate schemes heat pump water heating systems are becoming increasingly popular, but do they result in lower greenhouse gas emissions? This study follows on from a previous life cycle assessment study of domestic hot water systems to include heat pump systems. The streamlined life cycle assessment approach used focused on the use phase of the life cycle, which was found in the previous study to be where the majority of global warming potential (GWP impacts occurred. Data was collected from an Australian heat pump manufacturer and was modelled assuming installation within Australian climate zone 3 (AS/NZS 4234:2011. Several scenarios were investigated for the heat pumps including different sources of electricity (grid, photovoltaic solar modules, and batteries and the use of solar thermal panels. It was found that due to their higher efficiency heat pump hot water systems can result in significantly lower GWP than electric storage hot water systems. Further, solar thermal heat pump systems can have lower GWP than solar electric hot water systems that use conventional electric boosting. Additionally, the contributions of HFC refrigerants to GWP can be significant so the use of alternative refrigerants is recommended. Heat pumps combined with PV and battery technology can achieve the lowest GWP of all domestic hot water systems.

  6. Feasibility analysis of domestic solar water heating systems in Greece

    International Nuclear Information System (INIS)

    Kaldellis, J.K.; El Samani, K.; Koronakis, P.

    2005-01-01

    The excessive usage of fossil fuels has world-widely caused chain environmental consequences. An interesting solution to this problem is the systematic exploitation of available renewable energy sources, including solar energy. Greece is located in a major geographical region with an abundant and reliable supply of solar energy, even during the winter. In as much, one cannot disregard the significant dependency of the country on imported fuels, since almost 70% of its domestic energy consumption is covered by oil and natural gas imports. Despite the relative local sun abundance, during the last 10 years the local solar collectors market illustrates a sluggish behaviour, in comparison with the impressive numbers of sales during the 1980-1990 decade. At a first glance, such an occurrence characterizes a controversy. In an attempt to find a rational explanation of this peculiar situation, an integrated cost-benefit analysis is carried out taking into consideration the vast majority of the parameters affecting solar thermal energy production cost. The resulting numerical values are then compared with the corresponding ones coming from alternative hot-water production techniques. Accordingly, a quite extensive sensitivity analysis is carried out, in order to demonstrate the impact of the main techno-economic parameters on the fiscal behaviour of contemporary solar hot water production systems. The results obtained not only explain with sufficient accuracy the current local market situation but also demonstrate the specific actions that if realized they may boost solar collector sales in the corresponding local market. (author)

  7. Solar heating, cooling, and domestic hot water system installed at Kaw Valley State Bank and Trust Company, Topeka, Kansas. Final report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-11-01

    The building has approximately 5600 square feet of conditioned space. Solar energy is used for space heating, space cooling, and preheating domestic hot water (DHW). The solar energy system has an array of evacuated tube-type collectors with an area of 1068 square feet. A 50/50 solution of ethylene glycol and water is the transfer medium that delivers solar energy to a tube-in-shell heat exchanger that in turn delivers solar-heated water to a 1100 gallon pressurized hot water storage tank. When solar energy is insufficient to satisfy the space heating and/or cooling demand, a natural gas-fired boiler provides auxiliary energy to the fan coil loops and/or the absorption chillers. Extracts from the site files, specification references, drawings, and installation, operation and maintenance instructions are included.

  8. A predictive model for smart control of a domestic heat pump and thermal storage

    NARCIS (Netherlands)

    van Leeuwen, Richard Pieter; Gebhardt, I.; de Wit, J.B.; Smit, Gerardus Johannes Maria

    The purpose of this paper is to develop and validate a predictive model of a thermal storage which is charged by a heat pump and used for domestic hot water supply. The model is used for smart grid control purposes and requires measurement signals of flow and temperature at the inlet and outlet of

  9. Solar heating and domestic hot water system installed at North Dallas High School

    Science.gov (United States)

    1980-01-01

    The solar energy system located at the North Dallas High School, Dallas, Texas is discussed. The system is designed as a retrofit in a three story with basement, concrete frame high school building. Extracts from the site files, specification references for solar modification to existing building heating and domestic hot water systems, drawings, installation, operation and maintenance instructions are included.

  10. Evaluations of different domestic hot water preparing methods with ultra-low-temperature district heating

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2016-01-01

    of Legionella in the DHW (domestic hot water) and assure the comfortable temperature, all substations were installed with supplementary heating devices. Detailed measurements were taken in the substations, including the electricity demand of the supplementary heating devices. To compare the energy and economic......This study investigated the performances of five different substation configurations in single-family houses supplied with ULTDH (ultra-low-temperature district heating). The temperature at the heat plant is 46 degrees C and around 40 degrees C at the substations. To avoid the proliferation...... performance of the substations, separate models were built based on standard assumptions. The relative heat and electricity delivered for preparing DHW were calculated. The results showed that substations with storage tanks and heat pumps have high relative electricity demand, which leads to higher integrated...

  11. 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.

  12. An application of the gas-fired chilling and heating units to domestic houses

    Energy Technology Data Exchange (ETDEWEB)

    Choi, J.H.; Yang, Y.M.; Chae, J.M.; Bang, H.S.; Kwon, O.B.; Yoo, S.I.; Kim, T.H. [R and D Center, Korea Gas Co. (Korea); Lee, T.W.; Kim, T.H.; Kim, B.H.; Hwang, I.J.; Kim, J.Y.; Kim, C.D.; Park, S.J. [Korea Institute of Construction Technology (Korea)

    1999-10-01

    Following researches and considerations were performed in this study for an efficient application of gas-fired chilling and heating units to the residential buildings. (1) Status of domestic cooling and heating for residential building. (2) Various introduction schemes of outdoor unit. (3) Design exclusive area for the gas appliance and installation of it. (4) Ventilation of exhaust gas and heat. (5) Prepare the installation specifications or standards for gas-fired chilling and heating units. (6) Design technique of plumbing for cooling and heating. (7) Evaluation of unit's capacity considering the thermal load of domestic buildings. (8) Cooling and heating system with the unit. (9) Fundamental test for evaluation of applicability. (10) Actual design and construction of experimental house for an application and a demonstration of the developed gas units. (11) Field test for cooling and heating. (12) Evaluation of economic efficiency. (13) Establish a business potential. (14) Establishment of legal and systematic support, energy rate. (15) Troubleshooting in the course of development and application of the new gas appliance. 41 refs., 214 figs., 52 tabs.

  13. Integration of Space Heating and Hot Water Supply in Low Temperature District Heating

    DEFF Research Database (Denmark)

    Elmegaard, Brian; Ommen, Torben Schmidt; Markussen, Michael

    2014-01-01

    pipes, where the water is at the highest temperature. The heat loss may be lowered by decreasing the temperatures in the network for which reason low temperature networks are proposed as a low loss solution for future district heating. However, the heating demand of the consumers involve both domestic......District heating makes it possible to provide heat for many consumers in an efficient manner. In particular, district heating based on combined heat and power production is highly efficient. One disadvantage of district heating is that there is a significant heat loss from the pipes...... to the surrounding ground. In larger networks involving both transmission and distribution systems, the heat loss is most significant from the distribution network. An estimate is that about 80-90 % of the heat loss occurs in the distribution system. In addition, the heat loss is naturally highest from the forward...

  14. Utilising heat from nuclear waste for space heating

    International Nuclear Information System (INIS)

    Deacon, D.

    1982-01-01

    A heating unit utilising the decay heat from irradiated material comprises a storage envelope for the material associated with a heat exchange system, means for producing a flow of air over the heat exchange system to extract heat from the material, an exhaust duct capable of discharging the heated air to the atmosphere, and means for selectively diverting at least some of the heated air to effect the required heating. With the flow of air over the heat exchange system taking place by a natural thermosyphon process the arrangement is self regulating and inherently reliable. (author)

  15. Exergy performance of different space heating systems: A theoretical study

    DEFF Research Database (Denmark)

    Kazanci, Ongun Berk; Shukuya, Masanori; Olesen, Bjarne W.

    2016-01-01

    , the effects of floor covering resistance on the whole system performance were studied using two heat sources; a natural gas fired condensing boiler and an air-source heat pump. The heating systems were also compared in terms of auxiliary exergy use for pumps and fans. The low temperature floor heating system......Three space heating systems (floor heating with different floor covering resistances, radiator heating with different working temperatures, warm-air heating with and without heat recovery) were compared using a natural gas fired condensing boiler as the heat source. For the floor heating systems...... performed better than other systems in terms of exergy demand. The use of boiler as a heat source for a low-exergy floor heating system creates a mismatch in the exergy supply and demand. Although an air-source heat pump could be a better heat source, this depends on the origin of the electricity supplied...

  16. Simulation of a combined heating, cooling and domestic hot water system based on ground source absorption heat pump

    International Nuclear Information System (INIS)

    Wu, Wei; You, Tian; Wang, Baolong; Shi, Wenxing; Li, Xianting

    2014-01-01

    Highlights: • A combined heating/cooling/DHW system based on GSAHP is proposed in cold regions. • The soil imbalance is effectively reduced and soil temperature can be kept stable. • 20% and 15% of condensation/absorption heat is recovered by GSAHP to produce DHW. • The combined system can improve the primary energy efficiency by 23.6% and 44.4%. - Abstract: The amount of energy used for heating and domestic hot water (DHW) is very high and will keep increasing. The conventional ground source electrical heat pump used in heating-dominated buildings has the problems of thermal imbalance, decrease of soil temperature, and deterioration of heating performance. Ground source absorption heat pump (GSAHP) is advantageous in both imbalance reduction and primary energy efficiency (PEE) improvement; however, the imbalance is still unacceptable in the warmer parts of cold regions. A combined heating/cooling/DHW (HCD) system based on GSAHP is proposed to overcome this problem. The GSAHPs using generator absorber heat exchange (GAX) and single-effect (SE) cycles are simulated to obtain the performance under various working conditions. Different HCD systems in Beijing and Shenyang are simulated comparatively in TRNSYS, based on which the thermal imbalance, soil temperature, heat recovery, and energy efficiency are analyzed. Results show that GSAHP–GAX–HCD is suitable for Beijing and GSAHP–SE–HCD is suitable for Shenyang. The imbalance ratio can be reduced to −14.8% in Beijing and to 6.0% in Shenyang with an annual soil temperature variation of only 0.5 °C and 0.1 °C. Furthermore, about 20% and 15% of the total condensation/absorption heat is recovered to produce DHW, and the PEE can reach 1.516 in Beijing and 1.163 in Shenyang. The combined HCD systems can achieve a PEE improvement of 23.6% and 44.4% compared with the normal heating/cooling systems

  17. Performance of Space Heating in a Modern Energy System

    DEFF Research Database (Denmark)

    Elmegaard, Brian

    2011-01-01

    In the paper we study the performance of a number of heat supply technologies. The background of the study is the changes in the Danish energy systems over the last three decades which have caused integration of large shares of combined heat and power (CHP), renewable fuels and wind power....... These changes mean that there is a significant integration of electricity and heat supply in the system and that several technologies may be beneficial. In particular, heat pumps are under consideration and are often considered to be renewable energy. We study how to distribute fuel and emissions to the heat...... supply. We find that heat supply is low-efficient seen from an exergy viewpoint, between 1% and 26% utilization. As exergy is a quantification of primary energy, we conclude that far better utilization of primary energy is possible. We also find that combined heat and power and domestic heat pumps...

  18. Trading Places: Mary Shelley’s Argument with Domestic Space

    Directory of Open Access Journals (Sweden)

    Eve M. Lynch

    2013-04-01

    Full Text Available When Mary Shelley began writing The Last Man in 1824 in the wake of her husband Percy Bysshe Shelley’s untimely death, she drew from her close circle of family and friends as models for her main characters. Although it is tempting to view this novel as an autobiographical expiation of the profound sorrow that overwhelmed Shelley at her husband’s death, to do so is to underestimate her prescient political insight and to risk overlooking the complex implications of class and rank that suffuse the position of the narrator, Lionel Verney. While Shelley’s emotions give a passionate appeal to this novel, her intellectual ideas infuse the novel’s powerful critique of British governance. The Last Man is narrated in a political framework in which war and the clash of empires, parliamentary and republican conflict, turbulent revolution, and social and political corruption arrange the fates of the characters. In addition, the plague that silently and invisibly takes over Western Europe and England serves as a spectral process of corrosive malignity from outside, ensnaring all efforts to fix a domestic English system that is collapsing around individuals and the collective.

  19. A heat receiver design for solar dynamic space power systems

    Science.gov (United States)

    Baker, Karl W.; Dustin, Miles O.; Crane, Roger

    1990-01-01

    An advanced heat pipe receiver designed for a solar dynamic space power system is described. The power system consists of a solar concentrator, solar heat receiver, Stirling heat engine, linear alternator and waste heat radiator. The solar concentrator focuses the sun's energy into a heat receiver. The engine and alternator convert a portion of this energy to electric power and the remaining heat is rejected by a waste heat radiator. Primary liquid metal heat pipes transport heat energy to the Stirling engine. Thermal energy storage allows this power system to operate during the shade portion of an orbit. Lithium fluoride/calcium fluoride eutectic is the thermal energy storage material. Thermal energy storage canisters are attached to the midsection of each heat pipe. The primary heat pipes pass through a secondary vapor cavity heat pipe near the engine and receiver interface. The secondary vapor cavity heat pipe serves three important functions. First, it smooths out hot spots in the solar cavity and provides even distribution of heat to the engine. Second, the event of a heat pipe failure, the secondary heat pipe cavity can efficiently transfer heat from other operating primary heat pipes to the engine heat exchanger of the defunct heat pipe. Third, the secondary heat pipe vapor cavity reduces temperature drops caused by heat flow into the engine. This unique design provides a high level of reliability and performance.

  20. Micro tube heat exchangers for Space, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Mezzo fabricates micro tube heat exchangers for a variety of applications, including aerospace, automotive racing, Department of Defense ground vehicles, economizers...

  1. Evaluations of different domestic hot water preparing methods with ultra-low-temperature district heating

    International Nuclear Information System (INIS)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2016-01-01

    This study investigated the performances of five different substation configurations in single-family houses supplied with ULTDH (ultra-low-temperature district heating). The temperature at the heat plant is 46 °C and around 40 °C at the substations. To avoid the proliferation of Legionella in the DHW (domestic hot water) and assure the comfortable temperature, all substations were installed with supplementary heating devices. Detailed measurements were taken in the substations, including the electricity demand of the supplementary heating devices. To compare the energy and economic performance of the substations, separate models were built based on standard assumptions. The relative heat and electricity delivered for preparing DHW were calculated. The results showed that substations with storage tanks and heat pumps have high relative electricity demand, which leads to higher integrated costs considering both heat and electricity for DHW preparation. The substations with in-line electric heaters have low relative electricity usage because very little heat is lost due to the instantaneous DHW preparation. Accordingly, the substations with in-line electric heaters would have the lowest energy cost for DHW preparation. To achieve optimal design and operation for the ULTDH substation, the electricity peak loads of the in-line electric heaters were analysed according to different DHW-heating strategies. - Highlights: • Five different substations supplied with ultra-low-temperature district heating were measured. • The relative heat and electricity delivered for DHW preparation were modelled for different substations. • The levelized cost of the five substations in respect of DHW preparation was calculated. • The feasibility of applying instantaneous electric heater with normal power supply was tested.

  2. Heating and Domestic Hot Water Systems in Buildings Supplied by Low-Temperature District Heating

    DEFF Research Database (Denmark)

    Brand, Marek

    solutions simply redirect the bypassed water back to the DH network without additional cooling, but bypassed water can instead be redirected to floor heating in the bathroom to be further cooled and thus reduce heat loss from the DH network while improving comfort for occupants and still ensure fast DHW...... increased risk of Legionella if the DH substation and DHW system are designed for the low-temperature supply conditions. To ensure the fast provision of DHW during non-heating periods, the supply service pipe should be kept warm, preferably with the bypass solution redirecting the bypass flow to bathroom...... temperature. To accord with the literature, the modelling of internal heat gains reflected the improved efficiency of equipment by reduction of value from 5W/m2 to 4.2W/m2, also modelled as intermittent heat gains based on a realistic week schedule. Furthermore, the indoor set-point temperature was increased...

  3. Sizing Combined Heat and Power Units and Domestic Building Energy Cost Optimisation

    Directory of Open Access Journals (Sweden)

    Dongmin Yu

    2017-06-01

    Full Text Available Many combined heat and power (CHP units have been installed in domestic buildings to increase energy efficiency and reduce energy costs. However, inappropriate sizing of a CHP may actually increase energy costs and reduce energy efficiency. Moreover, the high manufacturing cost of batteries makes batteries less affordable. Therefore, this paper will attempt to size the capacity of CHP and optimise daily energy costs for a domestic building with only CHP installed. In this paper, electricity and heat loads are firstly used as sizing criteria in finding the best capacities of different types of CHP with the help of the maximum rectangle (MR method. Subsequently, the genetic algorithm (GA will be used to optimise the daily energy costs of the different cases. Then, heat and electricity loads are jointly considered for sizing different types of CHP and for optimising the daily energy costs through the GA method. The optimisation results show that the GA sizing method gives a higher average daily energy cost saving, which is 13% reduction compared to a building without installing CHP. However, to achieve this, there will be about 3% energy efficiency reduction and 7% input power to rated power ratio reduction compared to using the MR method and heat demand in sizing CHP.

  4. Titanium Loop Heat Pipes for Space Nuclear Radiators, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovation Research Phase I project will develop titanium Loop Heat Pipes (LHPs) that can be used in low-mass space nuclear radiators, such as...

  5. Solar Space and Water Heating for Hospital --Charlottesville, Virginia

    Science.gov (United States)

    1982-01-01

    Solar heating system described in an 86-page report consists of 88 single-glazed selectively-coated baseplate collector modules, hot-water coils in air ducts, domestic-hot-water preheat tank, 3,000 Gallon (11,350-1) concrete urethane-insulated storage tank and other components.

  6. Interactive Spaces: Towards Collaborative structuring and Ubiquitous Presentation in Domestic Environment

    DEFF Research Database (Denmark)

    Petersen, Marianne Graves; Grønbæk, Kaj

    2004-01-01

    collaborative structuring and ubiquitous presentation of materials in private homes. With DoHM we propose establishing new relationship between digital and physical hyperspaces, folding hyperspaces into the physical space of the household. Thus we strive to combine the qualities of physical domestic materials...... and spaces with the flexibility and dynamics of digital hyperspaces. We propose a variety of new ubiquitous home appliances called MediaWall, MediaTable, MediaTray and MediaPort, which address these issues....

  7. Interactive Spaces: Towards Collaborative Structuring and Ubiquitous Presentation in Domestic Environments

    DEFF Research Database (Denmark)

    Petersen, Marianne Graves; Grønbæk, Kaj

    2004-01-01

    collaborative structuring and ubiquitous presentation of materials in private homes. With DoHM we propose establishing new relationship between digital and physical hyperspaces, folding hyperspaces into the physical space of the household. Thus we strive to combine the qualities of physical domestic materials...... and spaces with the flexibility and dynamics of digital hyperspaces. We propose a variety of new ubiquitous home appliances called MediaWall, MediaTable, MediaTray and MediaPort, which address these issues....

  8. Microbial growth in domestic hot water systems with special emphasis on connections to district heating networks

    Energy Technology Data Exchange (ETDEWEB)

    Frederiksen, S [Lund Institute of Technology, Dept. of Heat and Power Engineering, Lund (SE); Krongaard Kristensen, K [Regional Food and Hygiene Authority, Koebenhavns Amt Vest, Glostrup (DK)

    1991-01-01

    It is by now well-estalished that domestic hot water systems often harbour Legionella bacteria. Measurements into a number of Danish systems have revealed many other bacteria, among them the thermophilic species Thermus, which is predominantly found on heating coils, where local temperatures are higher. This bacterium not only hampers heat transfer due to fouling, but may also be pathogenic, due to release of endotoxins. Its presence may explain a wide spectrum of symptoms experienced by people after hot baths, such as rashes and itching. The paper summarizes these findings, and on this basis engineering and microbiological considerations are presented in an effort to find ways of future control strategies that go beyond Legionella prevention. Special attention is given to district heating connections, in which low supply and return temperatures are generally wanted in the primary circuit. (author) 16 refs.

  9. Experimental investigation of a direct driven radial compressor for domestic heat pumps

    Energy Technology Data Exchange (ETDEWEB)

    Schiffmann, J. [Fischer Engineering Solutions AG, Birkenweg 3, CH-3360 Herzogenbuchsee (Switzerland); Favrat, D. [Ecole Polytechnique Federale de Lausanne, EPFL STI IGM LENI, Station 9, CH-1015 Lausanne (Switzerland)

    2009-12-15

    The presence of oil in domestic heat pumps is an obstacle toward higher efficiency, particularly for enhanced surface evaporators and for advanced concepts based on two-stage cycles. Very compact direct driven radial compressors supported on oil-free bearings represent a promising alternative. This paper presents the derivation of the specifications, the choice for an appropriate refrigerant fluid and the design of a proof of concept prototype with the various tradeoffs between the impeller characteristics to follow the seasonal heat demand, the bearing and rotordynamics for a stable operation. Heat pump simulation results, the design of the impeller as well as the layout of the experimental facility and first experimental results are presented. An impeller with a tip diameter of 20 mm has been tested at rotational speeds of up to 210 krpm reaching pressure ratios in excess of 3.3 and efficiencies above 78%. The refrigerant chosen for this first experimental approach is HFC 134a. (author)

  10. Research into properties of dust from domestic central heating boiler fired with coal and solid biofuels

    Directory of Open Access Journals (Sweden)

    Konieczyński Jan

    2017-06-01

    Full Text Available The aim of this research was to assess the content and composition of the pollutants emitted by domestic central heating boilers equipped with an automatic underfeed fuel delivery system for the combustion chamber. The comparative research was conducted. It concerned fuel properties, flue gas parameters, contents of dust (fl y ash and gaseous substances polluting the air in the flue gases emitted from a domestic CH boiler burning bituminous coal, pellets from coniferous wood, cereal straw, miscanthus, and sunflower husks, coniferous tree bark, and oats and barley grain. The emission factors for dust and gaseous air pollutants were established as they are helpful to assess the contribution of such boilers in the atmospheric air pollution. When assessing the researched boiler, it was found out that despite the development in design and construction, flue gases contained fly ash with a significant EC content, which affected the air quality.

  11. The role of domestic biomass in electricity, heat and grid balancing markets in Switzerland

    International Nuclear Information System (INIS)

    Panos, Evangelos; Kannan, Ramachandran

    2016-01-01

    The Swiss Energy Strategy targets to reduce per capita energy consumption, to decrease the share of fossil energy and to replace nuclear electricity generation by gains in efficiency and renewable energy sources. In view of the above objectives, we evaluated the prospects of biomass in stationary applications and grid balancing from an energy system perspective. We quantify a number of “what-if” scenarios using a cost-optimisation bottom-up model, with detailed representation of biomass production and use pathways, electricity and heat sectors, and grid ancillary services markets. The scenario analysis shows that domestic biomass can contribute 5–7% in electricity and 14–21% in heat production by 2050, depending on natural gas prices and climate policy intensity. Pooling of biogenic driven cogeneration plants can provide about 22–44% of the total secondary control power in 2050. Generally, biogenic technologies complement other assets in heat, electricity and ancillary services markets such as heat pumps, new renewable sources and hydropower. - Highlights: • Development and application of the Swiss TIMES electricity and heat system model. • Bioenergy supplies 5–7% of electricity and 14–21% of heat by 2050. • Biogenic gas driven CHP can provide 22–44% of secondary control power in 2050.

  12. Impact of domestic and tertiary buildings heating by natural gas in the Italian context

    International Nuclear Information System (INIS)

    Aste, Niccolò; Del Pero, Claudio

    2012-01-01

    Natural Gas (NG) is commonly used for satisfying population needs for heating, domestic hot water production and cooking, particularly in countries where the price of electricity is high. Typically, NG is extensively distributed on urbanized territory and can be exploited by using different technologies. As a consequence, primary energy is usually consumed directly in buildings, allowing high efficiency conversion but also producing pollutants in urban areas. In this paper a comprehensive analysis on NG use in the Italian domestic and tertiary building sector has been carried out, in order to evaluate energy and environmental impact of this fuel on different climatic and geographical contexts, also considering the temporal fluctuation of consumption. The aim of the work is to trace a reliable and up-to-date scenario of NG employment for building heating in Italy, which is one of the EU countries where this source is more widely used. The study was carried out under the research program “Analysis and evaluation of the current status of the reduction measures of environmental impacts due to heating energy consumption in Italy”, funded by the Italian Ministry of Environment. The data presented are an essential basis for the development of building energy efficiency and consumption rationalization policies. - Highlights: ► Detailed assessment of natural gas consumption and emission for residential and tertiary buildings heating in Italy. ► Estimation of the average specific primary energy consumption for households heating in different climatic contexts. ► Nationwide, it is the first study on the whole country with this level of detail.

  13. Green hypocrisy? Environmental attitudes and residential space heating expenditure

    OpenAIRE

    Traynor, Laura; Lange, Ian A.; Moro, Mirko

    2012-01-01

    In the UK, the largest proportion of household energy use is for space heating. Popular media make claims of a green hypocrisy: groups which have the strongest attitude towards the environment have the highest emissions. This study examines whether environmental attitudes and behaviours are associated with space heating energy use using data from the British Household Panel Survey. Results find that environmentally friendly attitudes generally do not lead to lower heating expenditures though ...

  14. Causes of Potential Urban Heat Island Space Using Heat flux Budget Under Urban Canopy

    Science.gov (United States)

    Kwon, Y. J.; Lee, D. K.

    2017-12-01

    Raised concerns about possible contribution from urban heat island to global warming is about 30 percent. Therefore, mitigating urban heat island became one of major issues to solve among urban planners, urban designers, landscape architects, urban affair decision makers and etc. Urban heat island effect on a micro-scale is influenced by factors such as wind, water vapor and solar radiation. Urban heat island effect on a microscale is influenced by factors like wind, water vapor and solar radiation. These microscopic climates are also altered by factors affecting the heat content in space, like SVF and aspect ratio depending on the structural characteristics of various urban canyon components. Indicators of heat mitigation in urban design stage allows us to create a spatial structure considering the heat balance budget. The spatial characteristics affect thermal change by varying heat storage, emitting or absorbing the heat. The research defines characteristics of the space composed of the factors affecting the heat flux change as the potential urban heat island space. Potential urban heat island spaces are that having higher heat flux than periphery space. The study is to know the spatial characteristics that affects the subsequent temperature rise by the heat flux. As a research method, four types of potential heat island space regions were analyzed. I categorized the spatial types by comparing parameters' value of energy balance in day and night: 1) day severe areas, 2) day comfort areas, 3) night severe areas, 4) night comfort areas. I have looked at these four types of potential urban heat island areas from a microscopic perspective and investigated how various forms of heat influences on higher heat flux areas. This research was designed to investigate the heat indicators to be reflected in the design of urban canyon for heat mitigation. As a result, severe areas in daytime have high SVF rate, sensible heat is generated. Day comfort areas have shadow effect

  15. Heat pipe nuclear reactor for space power

    Science.gov (United States)

    Koening, D. R.

    1976-01-01

    A heat-pipe-cooled nuclear reactor has been designed to provide 3.2 MWth to an out-of-core thermionic conversion system. The reactor is a fast reactor designed to operate at a nominal heat-pipe temperature of 1675 K. Each reactor fuel element consists of a hexagonal molybdenum block which is bonded along its axis to one end of a molybdenum/lithium-vapor heat pipe. The block is perforated with an array of longitudinal holes which are loaded with UO2 pellets. The heat pipe transfers heat directly to a string of six thermionic converters which are bonded along the other end of the heat pipe. An assembly of 90 such fuel elements forms a hexagonal core. The core is surrounded by a thermal radiation shield, a thin thermal neutron absorber, and a BeO reflector containing boron-loaded control drums.

  16. Modelling of air-conditioned and heated spaces

    Energy Technology Data Exchange (ETDEWEB)

    Moehl, U

    1987-01-01

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

  17. Green hypocrisy? Environmental attitudes and residential space heating expenditure

    Energy Technology Data Exchange (ETDEWEB)

    Traynor, Laura; Lange, Ian; Moro, Mirko [Stirling Univ. (United Kingdom). Division of Economics

    2012-06-15

    In the UK, the largest proportion of household energy use is for space heating. Popular media make claims of a green hypocrisy: groups which have the strongest attitude towards the environment have the highest emissions. This study examines whether environmental attitudes and behaviours are associated with space heating energy use using data from the British Household Panel Survey. Results find that environmentally friendly attitudes generally do not lead to lower heating expenditures though environmentally friendly behaviours are associated with lower heating expenditure. Also, the effect of these attitudes and behaviours do not change as income increase.

  18. More Wind Power Integration with Adjusted Energy Carriers for Space Heating in Northern China

    Directory of Open Access Journals (Sweden)

    Jianjun He

    2012-08-01

    Full Text Available In Northern China, due to the high penetration of coal-fired cogeneration facilities, which are generally equipped with extraction-condensing steam turbines, lots of wind power resources may be wasted during the heating season. In contrast, considerable coal is consumed in the power generation sector. In this article, firstly it is revealed that there exists a serious divergence in the ratio of electrical to thermal energy between end users’ demand and the cogenerations’ production during off-peak load at night, which may negate active power-balancing of the electric power grid. Secondly, with respect to this divergence only occurring during off-peak load at night, a temporary proposal is given so as to enable the integration of more wind power. The authors suggest that if the energy carrier for part of the end users’ space heating is switched from heating water to electricity (e.g., electric heat pumps (EHPs can provide space heating in the domestic sector, the ratio of electricity to heating water load should be adjusted to optimize the power dispatch between cogeneration units and wind turbines, resulting in fuel conservation. With this proposal, existing infrastructures are made full use of, and no additional ones are required. Finally a numerical simulation is performed in order to illustrate both the technical and economic feasibility of the aforementioned proposal, under ongoing infrastructures as well as electricity and space heating tariff conditions without changing participants’ benefits. The authors aim to persuade Chinese policy makers to enable EHPs to provide space heating to enable the integration of more wind power.

  19. Experimental studies on a ground coupled heat pump with solar thermal collectors for space heating

    International Nuclear Information System (INIS)

    Xi, Chen; Hongxing, Yang; Lin, Lu; Jinggang, Wang; Wei, Liu

    2011-01-01

    This paper presents experimental studies on a solar-assisted ground coupled heat pump (SAGCHP) system for space heating. The system was installed at the Hebei Academy of Sciences in Shijiazhuang (lat. N38 o 03', long. E114 o 26'), China. Solar collectors are in series connection with the borehole array through plate heat exchangers. Four operation modes of the system were investigated throughout the coldest period in winter (Dec 5th to Dec 27th). The heat pump performance, borehole temperature distributions and solar colleting characteristics of the SAGCHP system are analyzed and compared when the system worked in continuous or intermittent modes with or without solar-assisted heating. The SAGCHP system is proved to perform space heating with high energy efficiency and satisfactory solar fraction, which is a promising substitute for the conventional heating systems. It is also recommended to use the collected solar thermal energy as an alternative source for the heat pump instead of recharging boreholes for heat storage because of the enormous heat capacity of the earth. -- Highlights: → We study four working modes of a solar-assisted ground coupled heat pump. → The heating performance is in direct relation with the borehole temperature. → Solar-assisted heating elevates borehole temperature and system performance. → The system shows higher efficiency over traditional heating systems in cold areas. → Solar heat is not suggested for high temperature seasonal storage.

  20. Applications of Radiative Heating for Space Exploration

    Science.gov (United States)

    Brandis, Aaron

    2017-01-01

    Vehicles entering planetary atmospheres at high speeds (6 - 12 kms) experience intense heating by flows with temperatures of the order 10 000K. The flow around the vehicle experiences significant dissociation and ionization and is characterized by thermal and chemical non-equilibrium near the shock front, relaxing toward equilibrium. Emission from the plasma is intense enough to impart a significant heat flux on the entering spacecraft, making it necessary to predict the magnitude of radiative heating. Shock tubes represent a unique method capable of characterizing these processes in a flight-similar environment. The Electric Arc Shock tube (EAST) facility is one of the only facilities in its class, able to produce hypersonic flows at speeds up to Mach 50. This talk will review the characterization of radiation measured in EAST with simulations by the codes DPLR and NEQAIR, and in particular, focus on the impact these analyses have on recent missions to explore the solar system.

  1. National Deployment of Domestic Geothermal Heat Pump Technology: Observations on the UK Experience 1995–2013

    Directory of Open Access Journals (Sweden)

    Simon Rees

    2014-08-01

    Full Text Available Uptake of geothermal heat pump technology in the UK and corresponding development of a domestic installation industry has progressed significantly in the last decade. This paper summarizes the growth process and reviews the research that has been specifically concerned with conditions in the UK. We discuss the driving forces behind these developments and some of the supporting policy initiatives that have been implemented. Publically funded national trials were completed to assess the performance and acceptance of the technology and validate design and installation standards. We comment on both the technical and non-technical findings of the trials and the related academic research and their relevance to standards development. A number of technical issues can be identified—some of which may be particular to the UK—and we suggest a number of research and development questions that need to be addressed further. Current national support for the technology relies solely on a tariff mechanism and it is uncertain that this will be effective enough to ensure sufficient growth to meet the national renewable heat target in 2020. A broader package of support that includes mandatory measures applied to future housing development and retrofit may be necessary to ensure long-term plans for national deployment and decarbonization of heat are achieved. Industry needs to demonstrate that efficiency standards can be assured, capital costs reduced in the medium-term and that national training schemes are effective.

  2. The adjoint space in heat transport theory

    International Nuclear Information System (INIS)

    Dam, H. van; Hoogenboom, J.E.

    1980-01-01

    The mathematical concept of adjoint operators is applied to the heat transport equation and an adjoint equation is defined with a detector function as source term. The physical meaning of the solutions for the latter equation is outlined together with an application in the field of perturbation analysis. (author)

  3. Building Space Heating with a Solar-Assisted Heat Pump Using Roof-Integrated Solar Collectors

    Directory of Open Access Journals (Sweden)

    Zhiyong Yang

    2011-03-01

    Full Text Available A solar assisted heat pump (SAHP system was designed by using a roof-integrated solar collector as the evaporator, and then it was demonstrated to provide space heating for a villa in Tianjin, China. A building energy simulation tool was used to predict the space heating load and a three dimensional theoretical model was established to analyze the heat collection performance of the solar roof collector. A floor radiant heating unit was used to decrease the energy demand. The measurement results during the winter test period show that the system can provide a comfortable living space in winter, when the room temperature averaged 18.9 °C. The average COP of the heat pump system is 2.97 and with a maximum around 4.16.

  4. Solar thermal space heating combined with swimming pool heating: A promising solution for southern Europe climates

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, M.J.; Neves, Ana [INETI/DER, Lisboa (Portugal)

    2006-07-01

    The system concept evaluation performed focused on systems that can provide hot water, space heating and swimming-pool heating, and are designed for application in southern climates specifically for single-family houses. Due to the climate characteristics of southern Europe, space heating is required only for a few months in the year. In this evaluation it was considered a six month period for space heating and, on the other six months, swimming pool heating was considered. This type of systems are applicable to a niche market of people who are building their houses as single-family houses and want also to take profit of the good climate conditions for the use of solar energy. It is common that the construction of a swimming pool is also planned and constructed. The evaluation is made considering as reference system a factory made with 4m{sup 2} collector area and 300 l storage tank. The system in evaluation offers extra service - space heating and swimming pool heating and is formed by a collector field and a combistore providing solar hot water preparation and space heating in the winter period and providing also swimming pool heating in the summer period. The evaluation made shows that in southern Europe climates this system will give extra service in comparison to the traditional solar systems used and can be economically interesting.

  5. Absorption heat pump for space applications

    Science.gov (United States)

    Nguyen, Tuan; Simon, William E.; Warrier, Gopinath R.; Woramontri, Woranun

    1993-01-01

    In the first part, the performance of the Absorption Heat Pump (AHP) with water-sulfuric acid and water-magnesium chloride as two new refrigerant-absorbent fluid pairs was investigated. A model was proposed for the analysis of the new working pairs in a heat pump system, subject to different temperature lifts. Computer codes were developed to calculate the Coefficient of Performance (COP) of the system with the thermodynamic properties of the working fluids obtained from the literature. The study shows the potential of water-sulfuric acid as a satisfactory replacement for water-lithium bromide in the targeted temperature range. The performance of the AHP using water-magnesium chloride as refrigerant-absorbent pair does not compare well with those obtained using water-lithium bromide. The second part concentrated on the design and testing of a simple ElectroHydrodynamic (EHD) Pump. A theoretical design model based on continuum electromechanics was analyzed to predict the performance characteristics of the EHD pump to circulate the fluid in the absorption heat pump. A numerical method of solving the governing equations was established to predict the velocity profile, pressure - flow rate relationship and efficiency of the pump. The predicted operational characteristics of the EHD pump is comparable to that of turbomachinery hardware; however, the overall efficiency of the electromagnetic pump is much lower. An experimental investigation to verify the numerical results was conducted. The pressure - flow rate performance characteristics and overall efficiency of the pump obtained experimentally agree well with the theoretical model.

  6. Meeting residential space heating demand with wind-generated electricity

    International Nuclear Information System (INIS)

    Hughes, Larry

    2010-01-01

    Worldwide, many electricity suppliers are faced with the challenge of trying to integrate intermittent renewables, notably wind, into their energy mix to meet the needs of those services that require a continuous supply of electricity. Solutions to intermittency include the use of rapid-response backup generation and chemical or mechanical storage of electricity. Meanwhile, in many jurisdictions with lengthy heating seasons, finding secure and preferably environmentally benign supplies of energy for space heating is also becoming a significant challenge because of volatile energy markets. Most, if not all, electricity suppliers treat these twin challenges as separate issues: supply (integrating intermittent renewables) and demand (electric space heating). However, if space heating demand can be met from an intermittent supply of electricity, then both of these issues can be addressed simultaneously. One such approach is to use off-the-shelf electric thermal storage systems. This paper examines the potential of this approach by applying the output from a 5.15 MW wind farm to the residential heating demands of detached households in the Canadian province of Prince Edward Island. The paper shows that for the heating season considered, up to 500 households could have over 95 percent of their space heating demand met from the wind farm in question. The benefits as well as the limitations of the approach are discussed in detail. (author)

  7. Space Shuttle Orbiter AFT heat shield seal

    Science.gov (United States)

    Walkover, L. J.

    1979-01-01

    The evolution of the orbiter aft heat shield seal (AHSS) design, which involved advancing mechanical seal technology in severe thermal environment is discussed. The baseline design, various improvements for engine access, and technical problem solution are presented. It is a structure and mechanism at the three main propulsion system (MPS) engine interfaces to the aft compartment structure. Access to each MPS engine requires disassembly and removal of the AHSS. Each AHSS accommodates the engine movement, is exposed to an extremely high temperature environment, and is part of the venting control of the aft compartment.

  8. Reduction of Energy Consumption and CO2 Emissions in Domestic Water Heating by Means of Direct Expansion Solar Assisted Heat Pump

    International Nuclear Information System (INIS)

    Baleta, J.; Curko, T.; Cutic, T.; Pasanec, J.; Soldo, V.

    2012-01-01

    Domestic water heating in households sector is usually performed by either fossil fuel fired or electric boilers. Both the combustion process of the former and large electricity consumption of the latter strongly influence overall greenhouse gas emissions. Moreover, very high specific heat of water requires large quantity of energy for water heating making a significant impact on the overall energy consumption in the households sector whose total consumption of 80,81 PJ equals to 19,6% of total primary energy supply in Croatia in 2010. Considering the mentioned impact on energy consumption and CO 2 emissions as well as goals set by European Commission (so called 20-20-20), new technologies based on renewable energy sources are more than welcome in the field of domestic water heating. Direct expansion solar assisted heat pump is presented in this paper. Its working principle is based on single-stage vapour-compression cycle. Representing a gradual step to commercial application with a water tank of 300 l, the developed mobile unit is designed as a test rig enabling all necessary measurements to evaluate potential of solar irradiation for domestic water heating on various locations. Besides the unit description, trial testing results are presented and analyzed as well as a basic comparison of CO 2 emissions between solar assisted heat pump and conventionally used water heating systems. Taking into account both the decentralized water heating and favourable climatic conditions (especially along the Croatian Adriatic coast) as well as rising fossil fuel prices, it is expected that solar assisted heat pumps will be commercialized in the near future.(author)

  9. Experimental results of a 3 k Wh thermochemical heat storage module for space heating application

    NARCIS (Netherlands)

    Finck, C.J.; Henquet, E.M.R.; Soest, C.F.L. van; Oversloot, H.P.; Jong, A.J. de; Cuypers, R.; Spijker, J.C. van 't

    2014-01-01

    A 3 kWh thermochemical heat storage (TCS) module was built as part of an all-in house system implementation focusing on space heating application at a temperature level of 40 ºC and a temperature lift of 20 K. It has been tested and measurements showed a maximum water circuit temperature span

  10. Heat pumps in urban space heating systems: Energy and environmental aspects

    International Nuclear Information System (INIS)

    Carlini, M.; Impero Abenavoli, R.; Rome Univ. La Sapienza

    1991-01-01

    A statistical survey is conducted of air pollution in the city of Rome (Italy) due to conventional building space heating systems burning fossil fuels. The survey identifies the annual consumption of the different fuels and the relative amounts of the various pollutants released into the atmosphere by the heating plants, e.g., sulfur and nitrogen oxides, carbon monoxide, etc. Comparisons are then made between the ratios of urban heating plant air pollutants produced per tonne of fuel employed and those for ENEL (Italian National Electricity Board) coal, oil and natural gas fired power plants, in order to demonstrate the better environmental performances of the utility operated energy plants. The building space heating system energy consumption and pollution data are then used in a cost benefit analysis favouring the retrofitting of conventional heating systems with heat pump systems to obtain substantial reductions in energy consumption, heating bills and urban air pollution. The use of readily available, competitively priced and low polluting (in comparison with fuel oil and coal) methane as the energy source for space heating purposes is recommended. The paper also notes the versatility of the heat pump systems in that they could also be used for summer air conditioning

  11. The emissions from a space-heating biomass stove

    International Nuclear Information System (INIS)

    Koyuncu, T.; Pinar, Y.

    2007-01-01

    In this paper, the flue gas emissions of carbon monoxide (CO), nitrogen oxides (NO X ), sulphur dioxide (SO 2 ) and soot from an improved space-heating biomass stove and thermal efficiency of the stove have been investigated. Various biomass fuels such as firewood, wood shavings, hazelnut shell, walnut shell, peanut shell, seed shell of apricot (sweet and hot seed type), kernel removed corncob, wheat stalk litter (for cattle and sheep pen), cornhusk and maize stalk litter (for cattle pen) and charcoal were burned in the same space-heating biomass stove. Flue gas emissions were recorded during the combustion period at intervals of 5min. It was seen from the results that the flue gas emissions have different values depending on the characteristics of biomass fuels. Charcoal is the most appropriate biomass fuel for use in the space-heating biomass stoves because its combustion emits less smoke and the thermal efficiency of the stove is approximately 46%. (author)

  12. Design of annual storage solar space heating systems

    Energy Technology Data Exchange (ETDEWEB)

    Hooper, F C; Cook, J D

    1979-11-01

    Design considerations for annual storage solar space heating systems are discussed. A simulation model for the performance of suh systems is described, and a method of classifying system configurations is proposed. It is shown that annual systems sized for unconstrained performance, with no unused collector or storage capacity, and no rejected heat, minimize solar acquisition costs. The optimal performance corresponds to the condition where the marginal storage-to-collector sizing ratio is equal to the corresponding marginal cost ratio.

  13. Solar water heating systems feasibility for domestic requests in Tunisia: Thermal potential and economic analysis

    International Nuclear Information System (INIS)

    Hazami, Majdi; Naili, Nabiha; Attar, Issam; Farhat, Abdelhamid

    2013-01-01

    Highlights: • The present work studies the potential of using Domestic Solar Water Heating systems. • The payback period is between 8 and 7.5 years. • The annual savings in electrical energy is between 1316 and 1459 kW h/year. • The savings by using the solar systems is about 3969–4400.34 $. • The annual GHG emission per house is reduced by 27,800 tCO 2 . - Abstract: The main goal of the present work is to study the energetic and the economic potential of the deployment of Domestic Solar Water Heating systems (DSWHs) instead of using electric/gas/town gas water heaters. A case study related to Tunisian scenario was performed according to a typical Tunisian households composed of 4–5 persons. In this scenario we evaluated the performance and the life cycle perspective of the two most popular DSWHs over the recent years (i.e. DSWH with flat-plate solar collector, FPC, and DSWHs with evacuated-tube solar collector, ETC). The dynamic behavior of DSWHs according to Tunisian data weather was achieved by means of TRNSYS simulation. The Results showed that the FPC and ETC provide about 8118 and 12032 kW h/year of thermal energy. The economic potential of DSWHs in saving electricity and reducing carbon dioxide emissions was also investigated. Results showed that the annual savings in electrical energy relatively to the FPC and ETC are about 1316 and 1459 kW h/year, with a payback period of around 8 and 10 years, respectively. Based on gas/town gas water heater, the FPC and ETC save about 306 m 3 and 410 m 3 of gas/town gas with a payback period about 6 and 7.5 years, respectively. We found that the life cycle savings by installing the solar system instead of buying electricity to satisfy hot water needs are about $3969 (FPC) and $4400 (ETC). We establish also that the use of the DSWHs instead of installing gas/town gas water heaters save about $1518 (FPC) and $2035 (ETC). From an environmental point of view the annual GHG emission per house is reduced by 27800

  14. Validated TRNSYS Model for Solar Assisted Space Heating System

    International Nuclear Information System (INIS)

    Abdalla, Nedal

    2014-01-01

    The present study involves a validated TRNSYS model for solar assisted space heating system as applied to a residential building in Jordan using new detailed radiation models of the TRNSYS 17.1 and geometric building model Trnsys3d for the Google SketchUp 3D drawing program. The annual heating load for a building (Solar House) which is located at the Royal ScientiFIc Society (RS5) in Jordan is estimated under climatological conditions of Amman. The aim of this Paper is to compare measured thermal performance of the Solar House with that modeled using TRNSYS. The results showed that the annual measured space heating load for the building was 6,188 kWh while the heati.ng load for the modeled building was 6,391 kWh. Moreover, the measured solar fraction for the solar system was 50% while the modeled solar fraction was 55%. A comparison of modeled and measured data resulted in percentage mean absolute errors for solar energy for space heating, auxiliary heating and solar fraction of 13%, 7% and 10%, respectively. The validated model will be useful for long-term performance simulation under different weather and operating conditions.(author)

  15. Space qualification of high capacity grooved heat pipes

    Energy Technology Data Exchange (ETDEWEB)

    Dubois, M; Mullender, B; Druart, J [SABCA, Societe Anomyme Belgel de Construction Aeronautique (Belgium); Supper, W; Beddows, A [ESTEC-The (Netherlands)

    1997-12-31

    Based on the thermal requirements of the future telecommunication satellites, the development of a High Capacity Grooved Heat Pipe (HPG), was contracted by ESA to SABCA leading to an aluminium extruded heat pipe (outer diameter of 25 mm) based on a multi re-entrant grooves design. After an intensive acceptance test campaign whose results showed a good confidence in the design and the fulfillment of the required specifications of heat transport and on tilt capability (experimental maximum heat transport capability of 1500 Watt metres for a vapour temperature of 20 deg C), similar heat pipes have been developed with various outer diameters (11 mm, 15 mm and 20 mm) and with various shapes (circular outer shapes, integrated saddles). Several of these heat pipes were tested during two parabolic flight campaigns, by varying the heat loads during the micro-gravity periods. This HGP heat pipe family is now being submitted to a space qualification program according to ESA standards (ESA PSS-49), both in straight and bent configuration. Within this qualification, the heat pipes are submitted to an extended test campaign including environmental (random/sinus vibration, constant acceleration) and thermal tests (thermal performance, thermal cycle, thermal soak, ageing). (authors) 9 refs.

  16. Space qualification of high capacity grooved heat pipes

    Energy Technology Data Exchange (ETDEWEB)

    Dubois, M.; Mullender, B.; Druart, J. [SABCA, Societe Anomyme Belgel de Construction Aeronautique (Belgium); Supper, W.; Beddows, A. [ESTEC-The (Netherlands)

    1996-12-31

    Based on the thermal requirements of the future telecommunication satellites, the development of a High Capacity Grooved Heat Pipe (HPG), was contracted by ESA to SABCA leading to an aluminium extruded heat pipe (outer diameter of 25 mm) based on a multi re-entrant grooves design. After an intensive acceptance test campaign whose results showed a good confidence in the design and the fulfillment of the required specifications of heat transport and on tilt capability (experimental maximum heat transport capability of 1500 Watt metres for a vapour temperature of 20 deg C), similar heat pipes have been developed with various outer diameters (11 mm, 15 mm and 20 mm) and with various shapes (circular outer shapes, integrated saddles). Several of these heat pipes were tested during two parabolic flight campaigns, by varying the heat loads during the micro-gravity periods. This HGP heat pipe family is now being submitted to a space qualification program according to ESA standards (ESA PSS-49), both in straight and bent configuration. Within this qualification, the heat pipes are submitted to an extended test campaign including environmental (random/sinus vibration, constant acceleration) and thermal tests (thermal performance, thermal cycle, thermal soak, ageing). (authors) 9 refs.

  17. Active charge, passive discharge floor space heating system

    Energy Technology Data Exchange (ETDEWEB)

    Salt, H.; Mahoney, K.J.

    1987-01-01

    This space heating system has a rockbed beneath and in contact with the floor of a dwelling, which is heated by radiation and convection from the floor. The ability of the heating system to maintain comfort conditions with no additional energy input is discussed and it is shown that the system is more suitable for use in mild climates than severe ones. Experimental work on horizontal air flow rockbeds is reported and shows that shallow beds can be designed in the same way as vertical air flow beds. The influence of natural convection on the effective thermal conductivity of the experimental rockbeds is reported.

  18. Combined heat pump for sanitary hot water and space heating with CO{sub 2} as refrigerant; Kombineret brugsvands- og rumvarmepumpe med CO{sub 2} som koelemiddel

    Energy Technology Data Exchange (ETDEWEB)

    Schoen Poulsen, C. [Teknologisk Institut (Denmark)

    2006-05-19

    This project report describes the implementation of the Danish project called 'Combined heat pump for sanitary hot water and space heating with CO{sub 2} as refrigerant'. In the course of the project, a combined heat pump has been developed for heating sanitary hot water and producing domestic space heating. The project shows that CO2 has excellent properties in systems where a high temperature is desired on the gas cooler side and that it is possible to combine the production of sanitary hot water with the production of domestic space heating. During the project, a number of system solutions have been analysed and at the end of the project a prototype was built. It was tested in the laboratory according to a current Dutch standard for heat pumps for sanitary hot water. The prototype was constructed without the space heat part which solely has been analysed according to calculations. The reason is that there currently are no applicable European standards for the testing of combined systems and as the total efficiency of the system mainly depends on the temperature out of the gas cooler it was decided not to spend resources on the construction of the combined system in the prototype version of the unit. Instead, a number of proposals have been submitted to how the system with a space heat section could be constructed. The main components used in the prototype (compressor, exchangers, valve, control and tank) are all partly commercially available and therefore focus has been on the system construction. During the project, a number of CFD calculations have been carried out on the gas cooler in the hot water tank and the results show how important it is that the gas cooler is designed and placed correctly. The laboratory tests carried out on the unit show that the COP of the heat pump plant in connection with sanitary hot water tapping (according to Dutch standard) is 1.4 1.5 which is not immediately satisfactory. But when it is considered that the unit is a

  19. Outdoor test method to determine the thermal behavior of solar domestic water heating systems

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Valladares, O.; Pilatowsky, I. [Centro de Investigacion en Energia, Universidad Nacional Autonoma de Mexico, Privada Xochicalco, s/n, Colonia Centro, 62580 Temixco, Morelos (Mexico); Ruiz, V. [Escuela Tecnica Superior de Ingenieros, Universidad de Sevilla, Camino de los Descubrimientos, s/n, Isla de la Cartuja, 41092 Sevilla, Espana (Spain)

    2008-07-15

    The dynamics of the market, the generation of new promotion programs, fiscal incentives and many other factors are to be considered for the massive application of solar domestic water heating systems (SDWHS) mainly of the compact thermosiphon type, makes it necessary to choose simple and inexpensive procedure tests that permit to know their characteristic thermal behaviors without an official standard being necessary. Moreover, it allows the comparison among systems and offers enough and reliable information to consumers and manufacturers. In most developing countries, an official national standard for SDWHS is not available, therefore it is necessary to adopt an international test procedure in which the cost and time of implementation is very important. In this work, a simple and inexpensive test method to determine the thermal behavior of SDWHS is proposed. Even though these procedure tests do not have an official standard structure they permit, by comparing different solar systems under identical solar, ambient, and initial conditions, the experimental determination of: (a) the maximum available volume of water for solar heating; (b) water temperature increment and available thermal energy at the end of the day; (c) temperature profiles (stratification) and the average temperature in the storage tank after it is homogenized; (d) the average global thermal efficiency; (e) water temperature decrement and energy lost overnight; and (f) the relationship between hot water volume and solar collector area as function of the average heating temperature. An additional proposed test permits to know the heat losses caused by the reverse flow in the collector loop. These tests will be carried out independently of the configuration between the solar collector and the storage tank, the way the fluid circulates and the type of thermal exchange. The results of this procedure test can be very useful, firstly, for the local solar manufacturers' equipment in order to design

  20. Outdoor test method to determine the thermal behavior of solar domestic water heating systems

    International Nuclear Information System (INIS)

    Garcia-Valladares, O.; Pilatowsky, I.; Ruiz, V.

    2008-01-01

    The dynamics of the market, the generation of new promotion programs, fiscal incentives and many other factors are to be considered for the massive application of solar domestic water heating systems (SDWHS) mainly of the compact thermosiphon type, makes it necessary to choose simple and inexpensive procedure tests that permit to know their characteristic thermal behaviors without an official standard being necessary. Moreover, it allows the comparison among systems and offers enough and reliable information to consumers and manufacturers. In most developing countries, an official national standard for SDWHS is not available, therefore it is necessary to adopt an international test procedure in which the cost and time of implementation is very important. In this work, a simple and inexpensive test method to determine the thermal behavior of SDWHS is proposed. Even though these procedure tests do not have an official standard structure they permit, by comparing different solar systems under identical solar, ambient, and initial conditions, the experimental determination of: (a) the maximum available volume of water for solar heating; (b) water temperature increment and available thermal energy at the end of the day; (c) temperature profiles (stratification) and the average temperature in the storage tank after it is homogenized; (d) the average global thermal efficiency; (e) water temperature decrement and energy lost overnight; and (f) the relationship between hot water volume and solar collector area as function of the average heating temperature. An additional proposed test permits to know the heat losses caused by the reverse flow in the collector loop. These tests will be carried out independently of the configuration between the solar collector and the storage tank, the way the fluid circulates and the type of thermal exchange. The results of this procedure test can be very useful, firstly, for the local solar manufacturers' equipment in order to design and

  1. Hybrid Heat Pipes for Lunar and Martian Surface and High Heat Flux Space Applications

    Science.gov (United States)

    Ababneh, Mohammed T.; Tarau, Calin; Anderson, William G.; Farmer, Jeffery T.; Alvarez-Hernandez, Angel R.

    2016-01-01

    Novel hybrid wick heat pipes are developed to operate against gravity on planetary surfaces, operate in space carrying power over long distances and act as thermosyphons on the planetary surface for Lunar and Martian landers and rovers. These hybrid heat pipes will be capable of operating at the higher heat flux requirements expected in NASA's future spacecraft and on the next generation of polar rovers and equatorial landers. In addition, the sintered evaporator wicks mitigate the start-up problems in vertical gravity aided heat pipes because of large number of nucleation sites in wicks which will allow easy boiling initiation. ACT, NASA Marshall Space Flight Center, and NASA Johnson Space Center, are working together on the Advanced Passive Thermal experiment (APTx) to test and validate the operation of a hybrid wick VCHP with warm reservoir and HiK"TM" plates in microgravity environment on the ISS.

  2. Domestic hot water. Measurements of consumption and heat loss from circulation pipes; Varmt brugsvand. Maaling af forbrug og varmetab fra cirkulationsledninger

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, B.; Schroeder, F.; Bergsoee, N.C.

    2009-07-01

    It is likely that the production and distribution of domestic hot water (DHW) in buildings will constitute a dominant share of both the present and in particular future energy design requirements. The goal of this project has been to propose more energy efficient and environmentally friendly solutions for DHW systems based on analyses of existing conditions. The possibilities include new types of circulation pipes, which have the potential of a 40 per cent reduction of heat losses. In addition to the reduction of heat losses inside the building, a low return temperature from the hot water system will have a large impact on the heat losses from the district heating network when the building is being heated by district heating. The results of this project could influence not only future buildings but also existing buildings in case of renovation of the installations. In this project measurements of water and energy consumptions have been carried out in a number of buildings, and heat losses from the production of domestic hot water and the distribution lines have been measured. In addition to the measurements, analyses and simulations have been carried out. Two models have been developed: One of an apartment room with vertical pipes passing through the room, and one of a room above a basement with horizontal heating pipes. The models make it possible to assess how much of the heat loss from the heating pipes is utilised for space heating. The following recommendations are pointed out: 1) In large buildings e.g. apartment buildings and office buildings the technical installations should be provided with meters so that it is possible to separate the energy consumption for DHW, space heating and ventilation, respectively. 2) In new buildings and in case of retrofitting existing buildings, careful planning of the placement and disposition of hot water taps compared with the location of the hot water tank or heat exchanger is recommended. Also, the necessity of a

  3. Identification of domestic needs of modular HTR for electric and heat process industry in Indonesia

    International Nuclear Information System (INIS)

    Rusli, A.; Arbie, B.

    2000-01-01

    Identification of potential applications of the modular high temperature gas-cooled reactor (HTGR) in Indonesia has been carried out his was done by surveying and analysing the electric and industrial heat process which included captive power for household and industrial complexes in 13 regional operation areas covered by PT PLN National Electric Company. The area includes from the western Aceh to the eastern Irian Jaya, cities which are 6000 miles apart. Surveying was conducted for several parameters that electric and process heat demand in each region including captive power, geological characteristics of the region, distance of each region from conventional energy resources and the existence of petrochemical industries or other industries which use high temperatures (>500 deg C). In order to obtain a scale of priority in each region, credit points (1-3) and sensitivity factors (0-1) were applied to obtain the total significant value. The regions included are: the east cost of Sumatra, the north coast of Java, the west, south and east coat of Kalimantan as well as the south coast of Sulawesi, beyond which there are thousands of small islands that are safe from a geological and a tectonic point of view. In the preliminary survey, the analysation showed that Regions III, IV, XII and XIII have a high potential priority, followed by Regions I, II, VI, VIII and IX. The potential of domestic participation in the first and second unit was also investigated in relation to the possibility of implementing the HTGR project in Indonesia in the future, and it amounted to about 26% and 31% of the total cost for the first and second units, respectively. A summary of results is shown in Table 1. (authors)

  4. Earliest Deadline Control of a Group of Heat Pumps with a Single Energy Source

    NARCIS (Netherlands)

    Fink, J.; van Leeuwen, Richard Pieter

    2016-01-01

    In this paper, we develop and investigate the optimal control of a group of 104 heat pumps and a central Combined Heat and Power unit (CHP). The heat pumps supply space heating and domestic hot water to households. Each house has a buffer for domestic hot water and a floor heating system for space

  5. Energy, economy and exergy evaluations of the solutions for supplying domestic hot water from low-temperature district heating in Denmark

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2016-01-01

    . Evaluation models were built to investigate the energy, economy and exergy performances of the proposed domestic hot water systems in various configurations. The configurations of the devised domestic hot water substations were optimised to fit well with both low and ultra-low-temperature district heating...... °C and 50 °C district heating scenarios, while the individual micro tank solution consumed less energy and cost less in the 35 °C district heating scenario....

  6. Solar Space and Water Heating for School -- Dallas, Texas

    Science.gov (United States)

    1982-01-01

    90 page report gives overview of retrofitted solar space-heating and hot-water system installation for 61-year-old high school. Description, specifications, modifications, plan drawings for roof, three floors, basement, correspondence, and documents are part of report.

  7. Economic feasibility of solar water and space heating.

    Science.gov (United States)

    Bezdek, R H; Hirshberg, A S; Babcock, W H

    1979-03-23

    The economic feasibility in 1977 and 1978 of solar water and combined water and space heating is analyzed for single-family detached residences and multi-family apartment buildings in four representative U.S. cities: Boston, Massachusetts; Washington, D.C.; Grand Junction, Colorado; and Los Angeles, California. Three economic decision criteria are utilized: payback period, years to recovery of down payment, and years to net positive cash flow. The cost competitiveness of the solar systems compared to heating systems based on electricity, fuel oil, and natural gas is then discussed for each city, and the impact of the federal tax credit for solar energy systems is assessed. It is found that even without federal incentives some solar water and space heating systems are competitive. Enactment of the solar tax credit, however, greatly enhances their competitiveness. The implications of these findings for government tax and energy pricing policies are discussed.

  8. Density-Dependent Spacing Behaviour and Activity Budget in Pregnant, Domestic Goats (Capra hircus).

    Science.gov (United States)

    Vas, Judit; Andersen, Inger Lise

    2015-01-01

    Very little is known about the spacing behaviour in social groups of domestic goats (Capra hircus) in the farm environment. In this experiment, we studied interindividual distances, movement patterns and activity budgets in pregnant goats housed at three different densities. Norwegian dairy goats were kept in stable social groups of six animals throughout pregnancy at 1, 2 or 3 m2 per individual and their spacing behaviours (i.e., distance travelled, nearest and furthest neighbour distance) and activity budgets (e.g., resting, feeding, social activities) were monitored. Observations were made in the first, second and last thirds of pregnancy in the mornings, at noon and in the afternoons of each of these phases (4.5 hours per observation period). The findings show that goats held at animal densities of 2 and 3 m2 moved longer distances when they had more space per animal and kept larger nearest and furthest neighbour distances when compared to the 1 m2 per animal density. Less feeding activity was observed at the high animal density compared to the medium and low density treatments. The phase of gestation also had an impact on almost all behavioural variables. Closer to parturition, animals moved further distances and the increase in nearest and furthest neighbour distance was more pronounced at the lower animal densities. During the last period of gestation, goats spent less time feeding and more on resting, social behaviours and engaging in other various activities. Our data suggest that more space per goat is needed for goats closer to parturition than in the early gestation phase. We concluded that in goats spacing behaviour is density-dependent and changes with stages of pregnancy and activities. Finally, the lower density allowed animals to express individual preferences regarding spacing behaviour which is important in ensuring good welfare in a farming situation.

  9. Density-Dependent Spacing Behaviour and Activity Budget in Pregnant, Domestic Goats (Capra hircus.

    Directory of Open Access Journals (Sweden)

    Judit Vas

    Full Text Available Very little is known about the spacing behaviour in social groups of domestic goats (Capra hircus in the farm environment. In this experiment, we studied interindividual distances, movement patterns and activity budgets in pregnant goats housed at three different densities. Norwegian dairy goats were kept in stable social groups of six animals throughout pregnancy at 1, 2 or 3 m2 per individual and their spacing behaviours (i.e., distance travelled, nearest and furthest neighbour distance and activity budgets (e.g., resting, feeding, social activities were monitored. Observations were made in the first, second and last thirds of pregnancy in the mornings, at noon and in the afternoons of each of these phases (4.5 hours per observation period. The findings show that goats held at animal densities of 2 and 3 m2 moved longer distances when they had more space per animal and kept larger nearest and furthest neighbour distances when compared to the 1 m2 per animal density. Less feeding activity was observed at the high animal density compared to the medium and low density treatments. The phase of gestation also had an impact on almost all behavioural variables. Closer to parturition, animals moved further distances and the increase in nearest and furthest neighbour distance was more pronounced at the lower animal densities. During the last period of gestation, goats spent less time feeding and more on resting, social behaviours and engaging in other various activities. Our data suggest that more space per goat is needed for goats closer to parturition than in the early gestation phase. We concluded that in goats spacing behaviour is density-dependent and changes with stages of pregnancy and activities. Finally, the lower density allowed animals to express individual preferences regarding spacing behaviour which is important in ensuring good welfare in a farming situation.

  10. Density-Dependent Spacing Behaviour and Activity Budget in Pregnant, Domestic Goats (Capra hircus)

    Science.gov (United States)

    Vas, Judit; Andersen, Inger Lise

    2015-01-01

    Very little is known about the spacing behaviour in social groups of domestic goats (Capra hircus) in the farm environment. In this experiment, we studied interindividual distances, movement patterns and activity budgets in pregnant goats housed at three different densities. Norwegian dairy goats were kept in stable social groups of six animals throughout pregnancy at 1, 2 or 3 m2 per individual and their spacing behaviours (i.e. distance travelled, nearest and furthest neighbour distance) and activity budgets (e.g. resting, feeding, social activities) were monitored. Observations were made in the first, second and last thirds of pregnancy in the mornings, at noon and in the afternoons of each of these phases (4.5 hours per observation period). The findings show that goats held at animal densities of 2 and 3 m2 moved longer distances when they had more space per animal and kept larger nearest and furthest neighbour distances when compared to the 1 m2 per animal density. Less feeding activity was observed at the high animal density compared to the medium and low density treatments. The phase of gestation also had an impact on almost all behavioural variables. Closer to parturition, animals moved further distances and the increase in nearest and furthest neighbour distance was more pronounced at the lower animal densities. During the last period of gestation, goats spent less time feeding and more on resting, social behaviours and engaging in other various activities. Our data suggest that more space per goat is needed for goats closer to parturition than in the early gestation phase. We concluded that in goats spacing behaviour is density-dependent and changes with stages of pregnancy and activities. Finally, the lower density allowed animals to express individual preferences regarding spacing behaviour which is important in ensuring good welfare in a farming situation. PMID:26657240

  11. Simulation study on single family house with solar floor and domestic hot water heating system by EESLISM; EESLISM ni yoru taiyonetsu danbo kyuto jutaku no simulation

    Energy Technology Data Exchange (ETDEWEB)

    Roh, H; Udagawa, M [Kogakuin University, Tokyo (Japan)

    1997-11-25

    Indoor thermal conditions and energy performance were simulated, by the aid of EESLISM as a common simulation program for indoor thermal conditions and energy systems, for an actual two-storied single family house equipped with solar-heated floors and a domestic hot water (DHW) heating system, in order to investigate applicability of the simulation program. The house, built in Shibuya Ward in Tokyo, has a total floor area of 164m{sup 2}, with a living room, dining room and study heated by the solar system for a total floor area of 35m{sup 2}. A heat-storage tank is provided, dedicated to the DHW system. The solar collector is of flat type, with selectively light-absorbing planes, having a total collector area of 11.46m{sup 2}. The operating conditions of the floor-heating and DHW systems are almost reproduced. It is necessary to take surrounding conditions into consideration; solar radiation in daytime will be overestimated if adjacent buildings are neglected to give higher temperature in the space and on the wall on the south than the observed level. 6 refs., 5 figs., 1 tab.

  12. Transient heat pipe investigations for space power systems

    International Nuclear Information System (INIS)

    Merrigan, M.A.; Keddy, E.S.; Sena, J.T.

    1985-01-01

    A 4-meter long, high temperature, high power, molybdenum-lithium heat pipe has been fabricated and tested in transient and steady state operation at temperatures to 1500 K. Maximum power throughput during the tests was approximately 37 kW/cm 2 for the 1.4 cm diameter vapor space of the annular wick heat pipe. The evaporator flux density for the tests was 150.0 W/cm 2 over a length of 40 cm. Condenser length was approximately 3.0 m with radiant heat rejection from the condenser to a coaxial, water cooled radiation calorimeter. A variable radiation shield, controllable from the outside of the vacuum enclosure, was used to vary the load on the heat pipe during the tests. 1 ref., 9 figs

  13. Fascioliasis risk factors and space-time clusters in domestic ruminants in Bangladesh.

    Science.gov (United States)

    Rahman, A K M Anisur; Islam, S K Shaheenur; Talukder, Md Hasanuzzaman; Hassan, Md Kumrul; Dhand, Navneet K; Ward, Michael P

    2017-05-08

    A retrospective observational study was conducted to identify fascioliasis hotspots, clusters, potential risk factors and to map fascioliasis risk in domestic ruminants in Bangladesh. Cases of fascioliasis in cattle, buffalo, sheep and goats from all districts in Bangladesh between 2011 and 2013 were identified via secondary surveillance data from the Department of Livestock Services' Epidemiology Unit. From each case report, date of report, species affected and district data were extracted. The total number of domestic ruminants in each district was used to calculate fascioliasis cases per ten thousand animals at risk per district, and this was used for cluster and hotspot analysis. Clustering was assessed with Moran's spatial autocorrelation statistic, hotspots with the local indicator of spatial association (LISA) statistic and space-time clusters with the scan statistic (Poisson model). The association between district fascioliasis prevalence and climate (temperature, precipitation), elevation, land cover and water bodies was investigated using a spatial regression model. A total of 1,723,971 cases of fascioliasis were reported in the three-year study period in cattle (1,164,560), goats (424,314), buffalo (88,924) and sheep (46,173). A total of nine hotspots were identified; one of these persisted in each of the three years. Only two local clusters were found. Five space-time clusters located within 22 districts were also identified. Annual risk maps of fascioliasis cases correlated with the hotspots and clusters detected. Cultivated and managed (P fascioliasis in Bangladesh, respectively. Results indicate that due to land use characteristics some areas of Bangladesh are at greater risk of fascioliasis. The potential risk factors, hot spots and clusters identified in this study can be used to guide science-based treatment and control decisions for fascioliasis in Bangladesh and in other similar geo-climatic zones throughout the world.

  14. 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%.

  15. Space Launch System Base Heating Test: Experimental Operations & Results

    Science.gov (United States)

    Dufrene, Aaron; Mehta, Manish; MacLean, Matthew; Seaford, Mark; Holden, Michael

    2016-01-01

    NASA's Space Launch System (SLS) uses four clustered liquid rocket engines along with two solid rocket boosters. The interaction between all six rocket exhaust plumes will produce a complex and severe thermal environment in the base of the vehicle. This work focuses on a recent 2% scale, hot-fire SLS base heating test. These base heating tests are short-duration tests executed with chamber pressures near the full-scale values with gaseous hydrogen/oxygen engines and RSRMV analogous solid propellant motors. The LENS II shock tunnel/Ludwieg tube tunnel was used at or near flight duplicated conditions up to Mach 5. Model development was based on the Space Shuttle base heating tests with several improvements including doubling of the maximum chamber pressures and duplication of freestream conditions. Test methodology and conditions are presented, and base heating results from 76 runs are reported in non-dimensional form. Regions of high heating are identified and comparisons of various configuration and conditions are highlighted. Base pressure and radiometer results are also reported.

  16. Theoretical energy and exergy analyses of solar assisted heat pump space heating system

    Directory of Open Access Journals (Sweden)

    Atmaca Ibrahim

    2014-01-01

    Full Text Available Due to use of alternative energy sources and energy efficient operation, heat pumps come into prominence in recent years. Especially in solar-assisted heat pumps, sizing the required system is difficult and arduous task in order to provide optimum working conditions. Therefore, in this study solar assisted indirect expanded heat pump space heating system is simulated and the results of the simulation are compared with available experimental data in the literature in order to present reliability of the model. Solar radiation values in the selected region are estimated with the simulation. The case study is applied and simulation results are given for Antalya, Turkey. Collector type and storage tank capacity effects on the consumed power of the compressor, COP of the heat pump and the overall system are estimated with the simulation, depending on the radiation data, collector surface area and the heating capacity of the space. Exergy analysis is also performed with the simulation and irreversibility, improvement potentials and exergy efficiencies of the heat pump and system components are estimated.

  17. Endothermic technology for domestic houses

    International Nuclear Information System (INIS)

    Virk, G.S.

    2005-01-01

    The paper introduces the endothermic energy systems being developed for buildings. These use the concept of solar assisted heat pumps where thermal energy is harvested using large integrated solar collectors connected to energy stores. The low grade energy is upgraded using heat pumps to provide thermal energy effectively to a wide variety of applications for space heating and cooling and hot water. The domestic housing sector is focused upon here and a current EC funded project aimed at assessing the potential of the endothermic technology for providing the thermal energy for space heating and cooling and hot water is presented. (author)

  18. Investigation and optimisation of heat storage tanks for low-flow SDHW systems[Solar Domestic Hot Water

    Energy Technology Data Exchange (ETDEWEB)

    Knudsen, Soeren

    2004-07-01

    This thesis, 'Investigation and optimisation of heat storage tanks for low-flow SDHW systems', describes a study of the heat transfer and flow structure in vertical mantle heat exchangers for low-flow Solar Domestic Hot Water (SDHW) systems. The heat storage is a key component in SDHW systems and the vertical mantle heat exchanger is one of the most promising heat storage designs for low-flow SDHW systems. The study was carried out using a combination of experimental and numerical methods. Thermal experiments of mantle heat exchangers with different mantle inlet designs showed that the mantle inlet port with advantage can be located a distance from the top of the mantle. Consequently, the mantle heat exchangers marketed today can be improved by changing the mantle inlet position. The heat transfer and flow structure in mantle heat exchangers are rather complex and the thermal experiments were followed by investigations by means of advanced experimental and numerical techniques such as Particle Image Velocimetry (PIV) and Computational Fluid Dynamics (CFD). Using a transparent glass mantle tank, experimental flow visualisation was carried out with a PIV system. The flow structures inside the mantle and inside the tank were visualised and then compared with the flow structures predicted by CFD-models. The investigations showed that the CFD-models were able to model the flow in the mantle and in the tank correctly. The CFD-models were also validated by means of thermal experiments with a steel mantle tank. With the verified CFD-models, a parameter analysis was carried out for differently designed mantle heat exchangers for different typical conditions to reveal how the mantle tank parameters influence the flow structure and heat transfer in mantle heat exchangers. The heat transfer in the mantle near the mantle inlet port showed to be in the mixed convection regime, and as the distance from the inlet increased, natural convection started to dominate. The

  19. Alternative fuels in domestic heating markets. Experimental testing of n-butanol as component in domestic heating oil; Alternative fluessige Energietraeger im Raumwaermemarkt. Experimentelle Ueberpruefung von n-Butanol als Beimischung zu Heizoel EL

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, H.; Dohn, N.; Rheinberg, O. van [RWTH Aachen (Germany). OWI Oel-Waerme-Inst. GmbH

    2012-02-15

    N-butanol has already been tested successfully as partial substitute for diesel fuel. However, to date there are no corresponding studies available regarding the use of n-butanol as bio-component in domestic heating oil. Thus, physical and chemical norm parameters of n-butanol/heating oil blends and their combustion specific characteristics in steady operation were examined. The combustion of blends of domestic heating oil and butanol (up to 20 % (v/v)) in a common yellow burner did not indicate negative influence and did not yield a significant change in emissions of carbon monoxide, nitrogen oxides or soot. All tests were conducted without any modifications of the burner to the use of n-butanol. The flash point drops below the limit of 55 C with 1 % (v/v) butanol already and is therefore a flammable liquid. Its use as a substitute for heating oil is therefore limited by safety regulations. Practical applications of n-butanol as bio-component could be its utilization in low concentrations or in facilities providing suitable storage capabilities. (orig.)

  20. Energetic and financial evaluation of solar assisted heat pump space heating systems

    International Nuclear Information System (INIS)

    Bellos, Evangelos; Tzivanidis, Christos; Moschos, Konstantinos; Antonopoulos, Kimon A.

    2016-01-01

    Highlights: • Four solar heating systems are presented in this work. • Various combinations between solar collectors and heat pumps are presented. • The systems are compared energetically and financially. • The use of PV and an air source heat pump is the best choice financially. • The use of PVT with a water source heat pump is the best solution energetically. - Abstract: Using solar energy for space heating purposes consists an alternative way for substituting fossil fuel and grid electricity consumption. In this study, four solar assisted heat pump heating systems are designed, simulated and evaluated energetically and financially in order to determine the most attractive solution. The use of PV collectors with air source heat pump is compared to the use of FPC, PVT and FPC with PV coupled with a water source heat pump. A sensitivity analysis for the electricity cost is conducted because of the great variety of this parameter over the last years. The final results proved that for electricity cost up to 0.23 €/kW h the use of PV coupled with an air source heat pump is the most sustainable solution financially, while for higher electricity prices the coupling of PVT with an water source heat pump is the best choice. For the present electricity price of 0.2 €/kW h, 20 m"2 of PV is able to drive the air source heat pump with a yearly solar coverage of 67% leading to the most sustainable solution. Taking into account energetic aspects, the use of PVT leads to extremely low grid electricity consumption, fact that makes this technology the most environmental friendly.

  1. Combined Space and Water Heating: Next Steps to Improved Performance

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, B. [NorthernSTAR Building America Partnership, Minneapolis, MN (United States); Bohac, D. [NorthernSTAR Building America Partnership, Minneapolis, MN (United States); Huelman, P. [NorthernSTAR Building America Partnership, Minneapolis, MN (United States)

    2016-07-13

    A combined space- and water-heating (combi) system uses a high-efficiency direct-vent burner that eliminates safety issues associated with natural draft appliances. Past research with these systems shows that using condensing water heaters or boilers with hydronic air handling units can provide both space and water heating with efficiencies of 90% or higher. Improved controls have the potential to reduce complexity and improve upon the measured performance. This project demonstrates that controls can significantly benefit these first-generation systems. Laboratory tests and daily load/performance models showed that the set point temperature reset control produced a 2.1%-4.3% (20-40 therms/year) savings for storage and hybrid water heater combi systems operated in moderate-load homes.

  2. 47 CFR 25.262 - Licensing and domestic coordination requirements for 17/24 GHz BSS space stations.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Licensing and domestic coordination requirements for 17/24 GHz BSS space stations. 25.262 Section 25.262 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.262...

  3. Ventilation Heat Recovery from Wood-Burning Domestic Flues. A Theoretical Analysis Based on a Triple Concentric Tube Heat Exchanger

    Directory of Open Access Journals (Sweden)

    Lionel Druette

    2013-01-01

    Full Text Available This paper presents a new air-heating system concept for energy-efficient dwellings. It is a system designed to heat a low-energy building by coupling a heat-recovery ventilation system with a three-fluid heat exchanger located on the chimney of a wood-pellet stove. The proposed work focuses on the heat transfer that occurs between flue gases, the ventilation air and the combustion air within a triple concentric tube heat exchanger with no insulation at its outer surface. The main objective is to predict outlet temperature for the specific geometry of the heat exchanger studied here. Thus, the governing differential equations are derived for a counter-co-current flow arrangement of the three fluids. Then analytical solutions for the steady-state temperature distribution are obtained as well as the amount of heat transferred to the outside. An expression for the effectiveness of the heat exchanger is also proposed. Based on these results, calculations are performed on a case study to predict the fluid temperature distribution along the heat exchanger. Finally, a parametric study is carried out on this case study to assess the influence of the relevant parameters on the effectiveness of the heat exchanger. In addition, computation of heat losses to the outside justifies whether insulation is needed.

  4. A quasi-transient model of a transcritical carbon dioxide direct-expansion ground source heat pump for space and water heating

    International Nuclear Information System (INIS)

    Eslami-Nejad, Parham; Ouzzane, Mohamed; Aidoun, Zine

    2015-01-01

    In this study, a theoretical quasi-transient model is developed for detailed simulations of a carbon dioxide (CO_2) direct-expansion ground source heat pump (DX-GSHP). This model combines a transient analytical model for the ground, steady-state numerical models for the borehole and the gas cooler, as well as several thermodynamic models for the remaining components of a conventional heat pump, organized in interacting subroutines to form a powerful simulation tool. Extensive validation combining experimental data and CFD-generated results was performed for the borehole before the tool was used to simulate a practical application case. Performance is investigated for a system satisfying both space heating and domestic hot water requirements of a typical single family detached home in a cold climate region. The variation of different system parameters is also evaluated in this study. It is shown that CO_2 DX-GSHPs can offer relatively efficient and stable performance for integrated water and space heating applications. Furthermore, the importance of an accurate geothermal borehole sizing is highlighted for the DX-CO_2 heat pump systems. It is shown that, due to changes in the system working conditions, the total borehole length is not linearly correlated with the heat pump energy consumption and other parameters such as heat pump coefficient of performance and pressure drop in ground heat exchangers. Results showed that increasing the total borehole length of an optimum design (reference case study) by 25% decreases the total annual energy consumption by only 6%. However, reducing total borehole length of the reference case by 25% increases the total annual energy consumption by 10%. - Highlights: • A quasi-transient model for CO_2 direct-exchange ground-source heat pump is developed. • Validation combining experimental data and CFD-generated results was performed. • The effect of the borehole size on the design parameters is evaluated. • Results show that

  5. Exploring the belief systems of domestic abuse victims using Smallest Space Analysis (SSA)

    OpenAIRE

    Spruin, E.; Alleyne, E.; Baker, R.; Papadaki, I.; Franz, A.

    2017-01-01

    Purpose: Support service provisions for domestic abuse victims has typically focused on the immediate risk and etiological factors associated with abuse. Consequently, there is limited research exploring more persistent and pervasive factors involved in this cycle of abuse, such as subjective experiences and beliefs held by victims of domestic abuse. The current study is a preliminary exploration of the individual experience of domestic abuse including the belief systems of participants. Incr...

  6. Energy, economy and exergy evaluations of the solutions for supplying domestic hot water from low-temperature district heating in Denmark

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2016-01-01

    District heating in Denmark is going through the transition from 3rd generation (80/40 °C) to 4th generation (50-55 °C/25 °C) systems in,preparation for district heating based completely on renewable fuels by 2035. However, concern about Legionella growth and reduced comfort with low......-temperature domestic hot water supply may be discouraging the implementation of low-temperature district heating. Aimed at providing possible solutions, this study modelled various proposals for district heating systems with supply temperatures of 65 °C, 50 °C and 35 °C and for two different building topologies....... Evaluation models were built to investigate the energy, economy and exergy performances of the proposed domestic hot water systems in various configurations. The configurations of the devised domestic hot water substations were optimised to fit well with both low and ultra-low-temperature district heating...

  7. The relative competitive positions of the alternative means for domestic heating

    DEFF Research Database (Denmark)

    Torekov, M.S.; Bahnsen, N.; Qvale, Einar Bjørn

    2007-01-01

    This study strives to clarify to what extent the improved insulation of new buildings affects the economically rational choice of heating supply. In the Danish context, natural gas furnaces show to be economically rational for the society only in few cases. District heating should be advocated only...... for areas with a high concentration of heat demand, primarily areas with apartment buildings. An increased use of heat pumps (HP) should be advocated as the ambient air HP show to be the cheapest of the individual heating systems-and in most cases cheaper than the collective heating systems. The taxation...

  8. Solar-Heated and Cooled Office Building--Columbus, Ohio

    Science.gov (United States)

    1982-01-01

    Final report documents solar-energy system installed in office building to provide space heating, space cooling and domestic hot water. Collectors mounted on roof track Sun and concentrate rays on fluid-circulating tubes. Collected energy is distributed to hot-water-fired absorption chiller and space-heating and domestic-hot-water preheating systems.

  9. Monitoring of Danish marketed solar heating systems

    International Nuclear Information System (INIS)

    Ellehauge, K.

    1993-01-01

    The paper describes the monitoring of manufactured solar heating systems for domestic hot water combined with space heating and systems for domestic hot water only. Results from the monitoring of 5 marketed combined systems for domestic hot water and space heating are presented. The systems situated at one family houses at different sites in Denmark have been monitored from January/February 1992. For the detailed monitoring of manufactured systems only for domestic hot water a test facility for simultaneous monitoring of 5 solar heating systems has been established at the Thermal Insulation Laboratory. (au)

  10. Effect of Fuels and Domestic Heating Appliance Types on Emission Factors of Selected Organic Pollutants

    Czech Academy of Sciences Publication Activity Database

    Šyc, Michal; Horák, J.; Hopan, F.; Krpec, K.; Tomšej, T.; Ocelka, T.; Pekárek, Vladimír

    2011-01-01

    Roč. 45, č. 21 (2011), s. 9427-9434 ISSN 0013-936X R&D Projects: GA MŽP(CZ) SP/1A2/116/07 Institutional research plan: CEZ:AV0Z40720504 Keywords : domestic combustion * PCDD/F * emission factors Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 5.228, year: 2011

  11. Modeling of pancake frying with non-uniform heating source applied to domestic cookers

    DEFF Research Database (Denmark)

    Sanz-Serrano, F.; Sagues, C.; Feyissa, Aberham Hailu

    2016-01-01

    The design of domestic cooking stoves is usually optimized by performing time-consuming cooking experiments, often using frying of pancakes as a standard. Simulation of cooking processes may reduce the number of experiments used in the development of the cooking stoves, saving time and resources....

  12. Simulation of the interaction of a solar domestic hot water tank system with a compact plate heat exchanger

    Energy Technology Data Exchange (ETDEWEB)

    Nizami, D.J.; Lightstone, M.F. [McMaster Univ., Hamilton, ON (Canada). Dept. of Mechanical Engineering; Harrison, S.; Cruickshank, C. [Queen' s Univ., Kingston, ON (Canada). Dept. of Mechanical and Materials Engineering

    2008-08-15

    An external natural convection heat exchanger (NCHE) was used as an alternative to forced convection for transferring energy from solar collector loops to a hot water storage tank. A computational fluid dynamics (CFD) program was used to predict interactions between the natural convection-driven side-arm heat exchanger and a hot water storage tank. A solar domestic hot water tank with a vertical compact plate natural convection heat exchanger was modelled. In addition, the heat exchanger was modelled as a section of pipe with high flow resistance and a volumetric energy source. Transient analyses were conducted and the CFD model was then compared with data obtained from laboratory experiments. Simulations were conducted on the fluid domain in order to investigate the influence of the flow on the thermal stratification in the tank, the heat transfer inside the tank, and the natural convection in the tank loop. Buoyancy for an incompressible fluid with constant fluid properties was modelled using a Boussinesq approximation. Temperature distributions were measured as a function of time. Results of the study indicated that assuming a constant thermal expansion coefficient in evaluation buoyancy forces for a wide range of operating temperatures did not result in accurate predictions. Future studies will model natural convection with a full buoyancy model. 11 refs., 2 tabs., 5 figs.

  13. Domestic demand-side management (DSM): Role of heat pumps and thermal energy storage (TES) systems

    International Nuclear Information System (INIS)

    Arteconi, A.; Hewitt, N.J.; Polonara, F.

    2013-01-01

    Heat pumps are seen as a promising technology for load management in the built environment, in combination with the smart grid concept. They can be coupled with thermal energy storage (TES) systems to shift electrical loads from high-peak to off-peak hours, thus serving as a powerful tool in demand-side management (DSM). This paper analyzes heat pumps with radiators or underfloor heating distribution systems coupled with TES with a view to showing how a heat pump system behaves and how it influences the building occupants' thermal comfort under a DSM strategy designed to flatten the shape of the electricity load curve by switching off the heat pump during peak hours (16:00–19:00). The reference scenario for the analysis was Northern Ireland (UK). The results showed that the heat pump is a good tool for the purposes of DSM, also thanks to the use of TES systems, in particular with heating distribution systems that have a low thermal inertia, e.g. radiators. It proved possible to achieve a good control of the indoor temperature, even if the heat pump was turned off for 3 h, and to reduce the electricity bill if a “time of use” tariff structure was adopted. -- Highlights: ► Heat pump heating systems with thermal energy storage are considered. ► System behavior is investigated during a DSM strategy for reducing peak energy demand. ► Heat pump heating systems demonstrate to be able to have an active role in DSM programs. ► A TES system must be coupled with the heat pump in presence of low thermal inertia heating distribution systems. ► Central role played by incentives schemes to promote this technology

  14. Will domestic consumers take up the renewable heat incentive? An analysis of the barriers to heat pump adoption using agent-based modelling

    International Nuclear Information System (INIS)

    Snape, J.R.; Boait, P.J.; Rylatt, R.M.

    2015-01-01

    The UK Government introduced the tariff-based domestic Renewable Heat Incentive (RHI) in April 2014 to encourage installation of renewable heat technologies as a key component of its carbon reduction policy. Of these, heat pumps are considered to be the most promising for widespread adoption and as such are the subject of this paper. Pilot studies prior to introduction of the policy identified non-financial barriers to uptake, such as the “hassle factor” involved, and initial figures indeed indicate that uptake is lower than expected. We analyse these non-financial barriers using an agent-based model and conclude that there is a tipping point beyond which adoption is likely to fall very sharply. We suggest that the RHI’s complex and stringent compliance requirements for home inspections and heat emitter performance may well have driven adoption past this point and that further intervention may be required if the key aims of the RHI are to be achieved. -- Highlights: •We examine the uptake of the UK Renewable Heat Incentive (RHI). •We use Agent-based modelling to simulate uptake in a heterogeneous population. •Simulation modelling suggests that uptake is sensitive to non-financial barriers. •Non-financial barriers were introduced after RHI policy impact assessment. •New barriers combined with sensitivity could explain observed lower than expected uptake

  15. Energy, economy and exergy evaluations of the solutions for supplying domestic hot water from low-temperature district heating in Denmark

    International Nuclear Information System (INIS)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2016-01-01

    Highlights: • Provided domestic hot water configurations for low-temperature district heating. • Various building typologies and district heating supply temperatures were included. • Different scenarios were evaluated from the energy, economy and exergy aspects. • The benefits of lower return temperature to district heating were investigated. - Abstract: District heating in Denmark is going through the transition from 3rd generation (80/40 °C) to 4th generation (50–55 °C/25 °C) systems in preparation for district heating based completely on renewable fuels by 2035. However, concern about Legionella growth and reduced comfort with low-temperature domestic hot water supply may be discouraging the implementation of low-temperature district heating. Aimed at providing possible solutions, this study modelled various proposals for district heating systems with supply temperatures of 65 °C, 50 °C and 35 °C and for two different building topologies. Evaluation models were built to investigate the energy, economy and exergy performances of the proposed domestic hot water systems in various configurations. The configurations of the devised domestic hot water substations were optimised to fit well with both low and ultra-low-temperature district heating and to reduce the return temperature to district heating. The benefits of lower return temperatures were also analysed compared with the current district heating situation. The evaluation results show that the decentralized substation system with instantaneous heat exchanger unit performed better under the 65 °C and 50 °C district heating scenarios, while the individual micro tank solution consumed less energy and cost less in the 35 °C district heating scenario.

  16. Combined Space and Water Heating: Next Steps to Improved Performance

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, B. [NorthernSTAR Building America Partnership, Minneapolis, MN (United States); Bohac, D. [NorthernSTAR Building America Partnership, Minneapolis, MN (United States); Huelman, P. [NorthernSTAR Building America Partnership, Minneapolis, MN (United States)

    2016-07-13

    A combined space- and water-heating (combi) system uses a high-efficiency direct-vent burner that eliminates safety issues associated with natural draft appliances. Past research with these systems shows that using condensing water heaters or boilers with hydronic air handling units can provide both space and water heating with efficiencies of 90% or higher. Improved controls have the potential to reduce complexity and improve upon the measured performance. This project demonstrates that controls can significantly benefit these first-generation systems. Laboratory tests and daily load/performance models showed that the set point temperature reset control produced a 2.1%–4.3% (20–40 therms/year) savings for storage and hybrid water heater combi systems operated in moderate-load homes. The full modulation control showed additional savings over set point control (in high-load homes almost doubling the savings: 4%–5% over the no-control case). At the time of installation the reset control can be implemented for $200–$400, which would provide paybacks of 6–25 years for low-load houses and 3–15 years for high-load houses. Full modulation implementation costs would be similar to the outdoor reset and would provide paybacks of 5-½–20 years for low-load houses and 2-½–10 years for high-load houses.

  17. Energetical and ecological assessment of solar- and heat pump technologies for hot water preparation and space heating in Austria

    International Nuclear Information System (INIS)

    Faninger, G.

    1991-11-01

    Solar and heat pump systems have been proved in many applications on the market. To achieve an efficient energy output it is necessary to consider the special conditions of these technologies. The energetical and ecological criteria of solar and heat pump systems for hot water preparation and space heating are analysed on the basis of experimental data. (author)

  18. Installation package for a domestic solar heating and hot water system

    Science.gov (United States)

    1978-01-01

    The installation of two prototype solar heating and hot water systems is described. The systems consists of the following subsystems: solar collector, storage, control, transport, and auxiliary energy.

  19. Testing of Solar Heated Domestic Hot Water System for Solahart Scandinavia ApS

    DEFF Research Database (Denmark)

    Andersen, Elsa

    1997-01-01

    The solar heating system marketed by Solahart Scandinavia ApS was tested in the Institutes test facility for SDHWsystems. The test results are described in the report.......The solar heating system marketed by Solahart Scandinavia ApS was tested in the Institutes test facility for SDHWsystems. The test results are described in the report....

  20. Design, Development, and Performance Evaluation of Solar Heating System for Disinfection of Domestic Roof-Harvested Rainwater.

    Science.gov (United States)

    Akintola, O A; Sangodoyin, A Y

    2015-01-01

    A box-type solar heater was designed, constructed, and used to determine the effect of solar heating on quality of domestic roof-harvested rainwater (DRHRW). During testing, naturally contaminated DRHRW was harvested in Ibadan, Nigeria, and released into the system at 93.96 Lh(-1) (2.61 × 10(-5) m(3) s(-1)) in a continuous flow process. Water temperatures at inlet, within the heating chamber, and at outlet from the heating chamber and solar radiation were monitored at 10 min interval. Samples were collected at both inlet to and outlet from the heating chamber at 10 min interval for microbiological analysis. The highest plate stagnation temperature, under no-load condition, was 100°C. The solar water heater attained a maximum operational temperature of 75°C with 89.6 and 94.4% reduction in total viable count and total coliform count, respectively, while Escherichia coli and Staphylococcus aureus were completely eradicated at this temperature. The solar heater developed proved to be effective in enhancing potability of DRHRW in Ibadan, Nigeria. This may be an appropriate household water treatment technology for developing countries, hence, a way of resolving problem of low quality water for potable uses.

  1. Climate Adaptivity and Field Test of the Space Heating Used Air-Source Transcritical CO2 Heat Pump

    Science.gov (United States)

    Song, Yulong; Ye, Zuliang; Cao, Feng

    2017-08-01

    In this study, an innovation of air-sourced transcritical CO2 heat pump which was employed in the space heating application was presented and discussed in order to solve the problem that the heating performances of the transcritical CO2 heat pump water heater deteriorated sharply with the augment in water feed temperature. An R134a cycle was adopted as a subcooling device in the proposed system. The prototype of the presented system was installed and supplied hot water for three places in northern China in winter. The field test results showed that the acceptable return water temperature can be increased up to 55°C, while the supply water temperature was raised rapidly by the presented prototype to up to 70°C directly, which was obviously appropriate to the various conditions of heating radiator in space heating application. Additionally, though the heating capacity and power dissipation decreased with the decline in ambient temperature or the augment in water temperature, the presented heat pump system performed efficiently whatever the climate and water feed temperature were. The real time COP of the presented system was generally more than 1.8 in the whole heating season, while the seasonal performance coefficient (SPC) was also appreciable, which signified that the economic efficiency of the presented system was more excellent than other space heating approaches such as fuel, gas, coal or electric boiler. As a result, the novel system will be a promising project to solve the energy issues in future space heating application.

  2. Diffusion of innovative domestic heating systems and multi-storey wood-framed buildings in Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Mahapatra, Krushna

    2007-10-15

    The diffusion of innovations that promote sustainable use of forest resources and energy efficiency is important for reducing greenhouse gas emission and dependency on oil. In this thesis the 'systems of innovation' (SI) approach is used to analyse the diffusion of multi-storey wood-framed buildings and wood pellet heating systems in Sweden. The diffusion of an innovative heating system (IHS) is influenced by the diffusion of other types of IHSs, making it complex to analyse the diffusion of all these systems simultaneously using the SI approach. Hence, an 'adopter-centric' approach was used, as homeowners make the decision to adopt an IHS, which affects the rate of adoption of that system. The SI analyses showed that several sources of path dependency, resulting from the establishment and growth of the concrete-based construction system over the past 100 years, hinder the expansion of a wood-based multi-storey construction system. However, development of the wood construction system was possible due to government policies and funding, the wood industry's interest in expanding the market for value-added wood products, and the involvement of the wood research community. The growth of the pellet market was supported by national energy policy, the abundance of raw material and broad dissemination of district heating systems. However, a lack of co-ordination between the pellet and equipment suppliers in the early phase of market development, high annual operating cost, lack of information, dissatisfaction among early adopters and technology lock-in contributed to its relatively slow growth. The adopter-centric approach included household questionnaire surveys: one covering the whole of Sweden in 2004 involving 1500 randomly selected homeowners with any type of heating system, and another in the city of Oestersund in 2005 of 700 homeowners who had resistance heaters. The same homeowners in Oestersund were re-surveyed in 2006 to analyse the

  3. System design package for IBM system one: solar heating and domestic hot water

    Science.gov (United States)

    1977-01-01

    This report is a collation of documents and drawings that describe a prototype solar heating and hot water system using air as the collector fluid and a pebble bed for heat storage. The system was designed for installation into a single family dwelling. The description, performance specification, subsystem drawings, verification plan/procedure, and hazard analysis of the system was packaged for evaluation of the system with information sufficient to assemble a similar system.

  4. Ablative overlays for Space Shuttle leading edge ascent heat protection

    Science.gov (United States)

    Strauss, E. L.

    1975-01-01

    Ablative overlays were evaluated via a plasma-arc simulation of the ascent pulse on the leading edge of the Space Shuttle Orbiter. Overlay concepts included corkboard, polyisocyanurate foam, low-density Teflon, epoxy, and subliming salts. Their densities ranged from 4.9 to 81 lb per cu ft, and the thicknesses varied from 0.107 to 0.330 in. Swept-leading-edge models were fabricated from 30-lb per cu ft silicone-based ablators. The overlays were bonded to maintain the surface temperature of the base ablator below 500 F during ascent. Foams provided minimum-weight overlays, and subliming salts provided minimum-thickness overlays. Teflon left the most uniform surface after ascent heating.

  5. Heat and mass transport during microwave heating of mashed potato in domestic oven--model development, validation, and sensitivity analysis.

    Science.gov (United States)

    Chen, Jiajia; Pitchai, Krishnamoorthy; Birla, Sohan; Negahban, Mehrdad; Jones, David; Subbiah, Jeyamkondan

    2014-10-01

    A 3-dimensional finite-element model coupling electromagnetics and heat and mass transfer was developed to understand the interactions between the microwaves and fresh mashed potato in a 500 mL tray. The model was validated by performing heating of mashed potato from 25 °C on a rotating turntable in a microwave oven, rated at 1200 W, for 3 min. The simulated spatial temperature profiles on the top and bottom layer of the mashed potato showed similar hot and cold spots when compared to the thermal images acquired by an infrared camera. Transient temperature profiles at 6 locations collected by fiber-optic sensors showed good agreement with predicted results, with the root mean square error ranging from 1.6 to 11.7 °C. The predicted total moisture loss matched well with the observed result. Several input parameters, such as the evaporation rate constant, the intrinsic permeability of water and gas, and the diffusion coefficient of water and gas, are not readily available for mashed potato, and they cannot be easily measured experimentally. Reported values for raw potato were used as baseline values. A sensitivity analysis of these input parameters on the temperature profiles and the total moisture loss was evaluated by changing the baseline values to their 10% and 1000%. The sensitivity analysis showed that the gas diffusion coefficient, intrinsic water permeability, and the evaporation rate constant greatly influenced the predicted temperature and total moisture loss, while the intrinsic gas permeability and the water diffusion coefficient had little influence. This model can be used by the food product developers to understand microwave heating of food products spatially and temporally. This tool will allow food product developers to design food package systems that would heat more uniformly in various microwave ovens. The sensitivity analysis of this study will help us determine the most significant parameters that need to be measured accurately for reliable

  6. Standard Practice for Installation and Service of Solar Domestic Water Heating Systems for One- and Two-Family Dwellings

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1985-01-01

    1.1 This practice provides descriptions of solar domestic water heating systems and sets forth installation and service practices in new and existing one- and two-family dwellings to help ensure adequate operation and safety., 1.2 This practice applies regardless of the fraction of heating requirement supplied by solar energy, the type of conventional fuel used in conjunction with solar, or the heat transfer fluid (or fluids) used as the energy transport medium. However, where more stringent requirements are recommended by the manufacturer, these manufacturer requirements shall prevail. 1.3 The values stated in inch-pound units are to be regarded as the standard. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific precautionary statements, see Sections 6 and 7.

  7. Intersecting Spaces and Species: Women´s Bodies and the Domestic Sphere in Animal Rights Activism

    Directory of Open Access Journals (Sweden)

    Claudia Alonso Recarte

    2013-01-01

    Full Text Available The object of this article is to explore how current animal rights activism draws on images of women-animal corporeal hybrids to articulate a plight for animals, and how the domestic setting used in such campaigns is strategically conveyed to either instill sympathy or abhorrence at the ‘miscegenation’ of species within a single bodily space. I begin with a few observations on the matter of animal ontology in accordance with the muchdebated notion of commonness with humans (and in particular women. I then make a comparative analysis between video campaigns by two major animal rights organizations, the Royal Society for the Prevention of Cruelty to Animals (RSPCA and People for the Ethical Treatment of Animals (PETA to evaluate how their rhetoric of species hybridism conveys different assumptions regarding womanhood, and how domestic settings serve as instrumental tools through which to strengthen their rhetoric of animal liberation.

  8. The Importance of Heating System Transient Response in Domestic Energy Labelling

    Directory of Open Access Journals (Sweden)

    George Bennett

    2016-08-01

    Full Text Available European National Calculation Methods (NCM, such as the UK Standard Assessment Procedure (SAP, are used to make standardised and simplified assessments of building energy performance. These NCMs contain simplifications to aid ease of use and comparability of resulting Energy Performance Certificates (EPC. By comparing SAP with a modern, dynamic modelling system, this study quantifies internal temperatures and thereby heating energy consumption. Results show that for the considered test house SAP results correspond closely to a dynamic model using an idealistic heating system, with perfect control and instant responsiveness. However, the introduction of a dynamic, physically realistic gas fired boiler and water based heating system to the model results in a consistent increase in internal temperature (0.5 °C and energy demand (by ca. 1000 kWh/a. Variation of further parameters within the dynamic model, controls and heat source size, are presented and compared to SAP results and assumptions. The inclusion of more realistic dynamics in building energy modelling for NCMs may provide a better basis for effective decision making with respect to a wide range of heating systems.

  9. Assets of geothermal energy for buildings: heating, cooling and domestic hot water

    International Nuclear Information System (INIS)

    2016-01-01

    This publication first proposes a brief overview on the status, context and perspectives of geothermal energy in France by evoking the great number of heat pumps installed during the last decades and the choice made by public and private clients for this source of heating and cooling. While indicating how geothermal energy intervenes during a building project, this publication outlines that this energy is discrete and renewable, and that its technology is proven. Some examples are then evoked: use of geothermal energy for a public building in Saint-Malo, for estate projects near Paris, for a shopping centre in Roissy, and for office buildings

  10. System design package for SIMS prototype system 3, solar heating and domestic hot water

    Energy Technology Data Exchange (ETDEWEB)

    1978-11-01

    This report is a collation of documents and drawings that describe a prototype solar heating and hot water system using liquid flat plat collectors and a gas or electric furnace energy subsystem. The system was designed for installation into a single-family dwelling. The description, performance specification, subsystem drawings, verification plan/procedure, and hazard analysis of the system are packaged for evaluation of the system with information sufficient to assemble a similar system. The SIMS Prototype Heating and Hot Water System, Model Number 3 has been installed in a residence at Glendo State Park, Glendo, Wyoming.

  11. Annual analysis of heat pipe PV/T systems for domestic hot water and electricity production

    International Nuclear Information System (INIS)

    Pei Gang; Fu Huide; Ji Jie; Chow Tintai; Zhang Tao

    2012-01-01

    Highlights: ► A novel heat pipe photovoltaic/thermal system with freeze protection was proposed. ► A detailed annual simulation model for the HP-PV/T system was presented. ► Annual performance of HP-PV/T was predicted and analyzed under different condition. - Abstract: Heat-pipe photovoltaic/thermal (HP-PV/T) systems can simultaneously provide electrical and thermal energy. Compared with traditional water-type photovoltaic/thermal systems, HP-PV/T systems can be used in cold regions without being frozen with the aid of a carefully selected heat-pipe working fluid. The current research presents a detailed simulation model of the HP-PV/T system. Using this model, the annual electrical and thermal behavior of the HP-PV/T system used in three typical climate areas of China, namely, Hong Kong, Lhasa, and Beijing, are predicted and analyzed. Two HP-PV/T systems, with and without auxiliary heating equipment, are studied annually under four different kinds of hot-water load per unit collecting area (64.5, 77.4, 90.3, and 103.2 kg/m 2 ).

  12. Ascorbic acid and heat stress in domestic chicken nutrition: A review ...

    African Journals Online (AJOL)

    ... acid at required levels, especially under heat stress, improves growth, egg production, egg shell strength, fertility within(male and females) and hatchability of poultry eggs. The depressant effect of high temperature on performance often compels the technique of supplementing poultry diets to ensure optimum production.

  13. Heat pump evaluation for Space Station ATCS evolution

    Science.gov (United States)

    Ames, Brian E.; Petete, Patricia A.

    1991-01-01

    A preliminary feasibility assessment of the application of a vapor compression heat pump to the Active Thermal Control System (ATCS) of SSF is presented. This paper focuses on the methodology of raising the surface temperature of the radiators for improved heat rejection. Some of the effects of the vapor compression cycle on SSF examined include heat pump integration into ATCS, constraints on the heat pump operating parameters, and heat pump performance enhancements.

  14. Analysis and comparison of methods for the preparation of domestic hot water from district heating system, selected renewable and non-renewable sources in low-energy buildings

    Directory of Open Access Journals (Sweden)

    Knapik Maciej

    2018-01-01

    Full Text Available The article presents an economic analysis and comparison of selected (district heating, natural gas, heat pump with renewable energy sources methods for the preparation of domestic hot water in a building with low energy demand. In buildings of this type increased demand of energy for domestic hot water preparation in relation to the total energy demand can be observed. As a result, the proposed solutions allow to further lower energy demand by using the renewable energy sources. This article presents the results of numerical analysis and calculations performed mainly in MATLAB software, based on typical meteorological years. The results showed that system with heat pump and renewable energy sources Is comparable with district heating system.

  15. Analysis and comparison of methods for the preparation of domestic hot water from district heating system, selected renewable and non-renewable sources in low-energy buildings

    Science.gov (United States)

    Knapik, Maciej

    2018-02-01

    The article presents an economic analysis and comparison of selected (district heating, natural gas, heat pump with renewable energy sources) methods for the preparation of domestic hot water in a building with low energy demand. In buildings of this type increased demand of energy for domestic hot water preparation in relation to the total energy demand can be observed. As a result, the proposed solutions allow to further lower energy demand by using the renewable energy sources. This article presents the results of numerical analysis and calculations performed mainly in MATLAB software, based on typical meteorological years. The results showed that system with heat pump and renewable energy sources Is comparable with district heating system.

  16. System design package for SIMS Prototype System 4, solar heating and domestic hot water

    Energy Technology Data Exchange (ETDEWEB)

    1978-11-01

    This report is a collation of documents and drawings that describe a prototype solar heating and hot water system using air type solar energy collection techniques. The system consists of a modular designed prepackaged solar unit containing solar collctors, a rock storage container, blowers, dampers, ducting, air-to-water heat exchanger, DHW preheat tank, piping and system controls. The system was designed to be installed adjacent to a small single family dwelling. The description, performance specification, subsystem drawings, verification plan/procedure, and hazard analysis of the system are packaged for evaluation of the system with inforation sufficient to assemble a similar system. The prepackage solar unit has been installed at the Mississippi Power and Light Company, Training Facilities, Clinton, Mississippi.

  17. System design package for SIMS prototype system 4, solar heating and domestic hot water

    Science.gov (United States)

    1978-01-01

    The system consisted of a modular designed prepackaged solar unit, containing solar collectors, a rock storage container, blowers, dampers, ducting, air-to-water heat exchanger, DHW preheat tank, piping, and system controls. The system was designed to be installed adjacent to a small single family dwelling. The description, performance specification, subsystem drawings, verification plan/procedure, and hazard analysis of the system were packaged for evaluation.

  18. System Design Package for SIMS Prototype System 3, Solar Heating and Domestic Hot Water

    Science.gov (United States)

    1978-01-01

    A collation of documents and drawings are presented that describe a prototype solar heating and hot water system using liquid flat plate collectors and a gas or electric furnace energy subsystem. The system was designed for installation into a single-family dwelling. The description, performance specification, subsystem drawings, verification plan/procedure, and hazard analysis of the system are packaged for evaluation of the system with information sufficient to assemble a similar system.

  19. VICTORIA PARK: A DEMOCTRATIC PUBLIC OPEN SPACE FOR INDONESIA DOMESTIC HELPERS (TKW

    Directory of Open Access Journals (Sweden)

    Parmonangan Manurung

    2016-01-01

    Full Text Available Victoria Park is the largest city park in Hong Kong. This city park is not only known in Hong Kong, but also very well known in Indonesia as a gathering place for Indonesia domestic helpers (TKW in Hong Kong. This research tried to find out some determinant factors that have been affected the public open spac of Victoria Park to be a gathering place for thousands of TKW in Sunday and holidays as their day off. In order to get the results of research, some methodological research had been conducted such as: observation (survey, mapping, interviews and literature studies. The results showed that Victoria Park has a number of factors capable of meeting the needs of domestic help-ers in Hong Kong, these factors consist of internal factors and external factors. Internally, the character and functions held Victoria Park became a very influential factor, while externally, the accessibility and support functions around Victoria Park also has a considerable influence.

  20. Theoretical model and experimental validation of a direct-expansion solar assisted heat pump for domestic hot water applications

    International Nuclear Information System (INIS)

    Moreno-Rodríguez, A.; González-Gil, A.; Izquierdo, M.; Garcia-Hernando, N.

    2012-01-01

    This paper has shown the development of a theoretical model to determine the operating parameters and consumption of a domestic hot water (DHW) installation, which uses a direct-expansion solar assisted heat pump (DXSAHP) with refrigerant R-134a, a compressor with a rated capacity of 1.1 kW and collectors with a total area of 5.6 m 2 . The model results have been compared and validated the experimental results obtained with the equipment installed at the University Carlos III, South of Madrid. The analysis was conducted over the course of a year, and the results have been represented depending on the meteorological and process variables of several representative days. Taking into account the thermal losses of the installation and the dependency on the operating conditions, the acquired experimental coefficient of performance is between 1.7 and 2.9, while the DHW tank temperature over the course of the study is 51 °C. -- Highlights: ► The study aims to present a new theoretical model and an experimental validation. ► The experimental COP vary between 1.7 and 2.9 (max. condensation temperature 57 °C). ► The operating parameters respond to the solar radiation. The COP may increase up to 50%. ► The useful surface area varies between 50% and 85% of the total surface. ► The system stops if conditions exceed the maximum value of the absorbed heat.

  1. ‘That’s when we started using the living room’ : lessons from a local history of domestic heating in the United Kingdom

    NARCIS (Netherlands)

    Kuijer, L.; Watson, M.

    Indoor climate control forms a major share of residential energy demand. Policy measures to curb this demand tend to focus on energy-efficient technologies. However, while the energy efficiency of domestic heat provision in the United Kingdom (UK) has increased considerably over the past century,

  2. Residential solar-heating system

    Science.gov (United States)

    1978-01-01

    Complete residential solar-heating and hot-water system, when installed in highly-insulated energy-saver home, can supply large percentage of total energy demand for space heating and domestic hot water. System which uses water-heating energy storage can be scaled to meet requirements of building in which it is installed.

  3. Post-evaluation of a ground source heat pump system for residential space heating in Shanghai China

    Science.gov (United States)

    Lei, Y.; Tan, H. W.; Wang, L. Z.

    2017-11-01

    Residents of Southern China are increasingly concerned about the space heating in winter. The chief aim of the present work is to find a cost-effective way for residential space heating in Shanghai, one of the biggest city in south China. Economic and energy efficiency of three residential space heating ways, including ground source heat pump (GSHP), air source heat pump (ASHP) and wall-hung gas boiler (WHGB), are assessed based on Long-term measured data. The results show that the heat consumption of the building is 120 kWh/m2/y during the heating season, and the seasonal energy efficiency ratio (SEER) of the GSHP, ASHP and WHGB systems are 3.27, 2.30, 0.88 respectively. Compared to ASHP and WHGB, energy savings of GSHP during the heating season are 6.2 kgce/(m2.y) and 2.2 kgce/(m2.y), and the payback period of GSHP are 13.3 and 7.6 years respectively. The sensitivity analysis of various factors that affect the payback period is carried out, and the results suggest that SEER is the most critical factor affecting the feasibility of ground source heat pump application, followed by building load factor and energy price factor. These findings of the research have led the author to the conclusion that ground source heat pump for residential space heating in Shanghai is a good alternative, which can achieve significant energy saving benefits, and a good system design and operation management are key factors that can shorten the payback period.

  4. Reducing domestic heating demand: Managing the impact of behavior-changing feedback devices via marketing.

    Science.gov (United States)

    Jensen, Thorben; Chappin, Émile J L

    2017-07-15

    Feedback devices can be used to inform households about their energy-consumption behavior. This may persuade them to practice energy conservation. The use of feedback devices can also-via word of mouth-spread among households and thereby support the spread of the incentivized behavior, e.g. energy-efficient heating behavior. This study investigates how to manage the impact of these environmental innovations via marketing. Marketing activities can support the diffusion of devices. This study aims to identify the most effective strategies of marketing feedback devices. We did this by adapting an agent-based model to simulate the roll-out of a novel feedback technology and heating behavior within households in a virtual city. The most promising marketing strategies were simulated and their impacts were analyzed. We found it particularly effective to lend out feedback devices to consumers, followed by leveraging the social influence of well-connected individuals, and giving away the first few feedback devices for free. Making households aware of the possibility of purchasing feedback devices was found to be least effective. However, making households aware proved to be most cost-efficient. This study shows that actively managing the roll-out of feedback devices can increase their impacts on energy-conservation both effectively and cost-efficiently. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Validation and use of a simplified model of heat flows in domestic dwellings

    Energy Technology Data Exchange (ETDEWEB)

    Boland, J. [Flinders Univ. of South Australia, Bedford Park, SA (Australia)

    1995-12-31

    In order to persuade architects, planners or owner-builders to include energy efficiency as one of the criteria to use when designing a new house or retrofitting an old one, it is necessary to be able to quantify the benefit to them. In order to evaluate the thermal performance of a dwelling, one must solve heat transfer equations in what is a network of feedback loops representing the thermal pathways contained in it. An extensive investigation of the climatic drivers of the system, solar irradiation and ambient temperature, has led to the construction of a simplified model describing the heat flows in dwellings without resorting to numerical simulation. This paper gives a brief description of the model, called Magpie and a comparison of the results obtained using the Commonwealth Scientific and Industrial Research Organisation (CSIRO) developed model, Cheetah. It describes the uses of the model, which include calculating the probability of overheating in the summer and sensitivity analysis for design alteration. (author). 2 tabs., 1 fig., 14 refs.

  6. Heat pipes with variable thermal conductance property for space applications

    Energy Technology Data Exchange (ETDEWEB)

    Kravets, V.; Alekseik, Ye.; Alekseik, O.; Khairnasov, S. [National Technical University of Ukraine, Kyiv (Ukraine); Baturkin, V.; Ho, T. [Explorationssysteme RY-ES, Bremen (Germany); Celotti, L. [Active Space Technologies GmbH, Berlin (Germany)

    2017-06-15

    The activities presented in this paper demonstrate a new approach to provide passive thermal control using heat pipes, as demonstrated on the electronic unit of DLR’s MASCOT lander, which embarked on the NEA sample return mission Hayabusa 2 (JAXA). The focus is on the development and testing of heat pipes with variable thermal conductance in a predetermined temperature range. These heat pipes act as thermal switches. Unlike standard gasloaded heat pipes and thermal-diode heat pipes construction of presented heat pipes does not include any additional elements. Copper heat pipes with metal fibrous wicks were chosen as baseline design. We obtained positive results by choosing the heat carrier and structural parameters of the wick (i.e., pore diameter, porosity, and permeability). The increase in the thermal conductivity of the heat pipes from 0.04 W/K to 2.1 W/K was observed in the temperature range between −20 °C and +55 °C. Moreover, the heat pipes transferred the predetermined power of not less than 10 W within the same temperature range. The heat pipes have been in flight since December 2014, and the supporting telemetry data were obtained in September 2015. The data showed the nominal operation of the thermal control system.

  7. Changes in domestic heating fuel use in Greece: effects on atmospheric chemistry and radiation

    Science.gov (United States)

    Athanasopoulou, Eleni; Speyer, Orestis; Brunner, Dominik; Vogel, Heike; Vogel, Bernhard; Mihalopoulos, Nikolaos; Gerasopoulos, Evangelos

    2017-09-01

    For the past 8 years, Greece has been experiencing a major financial crisis which, among other side effects, has led to a shift in the fuel used for residential heating from fossil fuel towards biofuels, primarily wood. This study simulates the fate of the residential wood burning aerosol plume (RWB smog) and the implications on atmospheric chemistry and radiation, with the support of detailed aerosol characterization from measurements during the winter of 2013-2014 in Athens. The applied model system (TNO-MACC_II emissions and COSMO-ART model) and configuration used reproduces the measured frequent nighttime aerosol spikes (hourly PM10 > 75 µg m-3) and their chemical profile (carbonaceous components and ratios). Updated temporal and chemical RWB emission profiles, derived from measurements, were used, while the level of the model performance was tested for different heating demand (HD) conditions, resulting in better agreement with measurements for Tmin < 9 °C. Half of the aerosol mass over the Athens basin is organic in the submicron range, of which 80 % corresponds to RWB (average values during the smog period). Although organic particles are important light scatterers, the direct radiative cooling of the aerosol plume during wintertime is found low (monthly average forcing of -0.4 W m-2 at the surface), followed by a minor feedback to the concentration levels of aerosol species. The low radiative cooling of a period with such intense air pollution conditions is attributed to the timing of the smog plume appearance, both directly (longwave radiation increases during nighttime) and indirectly (the mild effect of the residual plume on solar radiation during the next day, due to removal and dispersion processes).

  8. Model of a thermal energy storage device integrated into a solar assisted heat pump system for space heating

    International Nuclear Information System (INIS)

    Badescu, Viorel

    2003-01-01

    Details about modelling a sensible heat thermal energy storage (TES) device integrated into a space heating system are given. The two main operating modes are described. Solar air heaters provide thermal energy for driving a vapor compression heat pump. The TES unit ensures a more efficient usage of the collected solar energy. The TES operation is modeled by using two non-linear coupled partial differential equations for the temperature of the storage medium and heat transfer fluid, respectively. Preliminary results show that smaller TES units provide a higher heat flux to the heat pump vaporiser. This makes the small TES unit discharge more rapidly during time periods with higher thermal loads. The larger TES units provide heat during longer time periods, even if the heat flux they supply is generally smaller. The maximum heat flux is extracted from the TES unit during the morning. Both the heat pump COP and exergy efficiency decrease when the TES unit length increases. Also, the monthly thermal energy stored by the TES unit and the monthly energy necessary to drive the heat pump compressor are increased by increasing the TES unit length

  9. Fuel savings with conventional hot water space heating systems by incorporating a natural gas powered heat pump. Preliminary project: Development of heat pump technology

    Science.gov (United States)

    Vanheyden, L.; Evertz, E.

    1980-12-01

    Compression type air/water heat pumps were developed for domestic heating systems rated at 20 to 150 kW. The heat pump is driven either by a reciprocating piston or rotary piston engine modified to operate on natural gas. Particular features of natural gas engines as prime movers, such as waste heat recovery and variable speed, are stressed. Two systems suitable for heat pump operation were selected from among five different mass produced car engines and were modified to incorporate reciprocating piston compressor pairs. The refrigerants used are R 12 and R 22. Test rig data transferred to field conditions show that the fuel consumption of conventional boilers can be reduced by 50% and more by the installation of engine driven heat pumps. Pilot heat pumps based on a 1,600 cc reciprocating piston engine were built for heating four two-family houses. Pilot pump operation confirms test rig findings. The service life of rotary piston and reciprocating piston engines was investigated. The tests reveal characteristic curves for reciprocating piston engines and include exhaust composition measurements.

  10. Fiscal space for domestic funding of health and other social services.

    Science.gov (United States)

    Meheus, Filip; McIntyre, Di

    2017-04-01

    To progress toward universal health coverage and promote inclusive social and economic development, it will be necessary to strengthen domestic resource mobilization for health. In this paper, we examine options for increasing domestic government revenue in low- and middle-income countries. We analyze the relationship between level of economic development and levels of government revenue and expenditure, and show that a country's level of economic development does not predetermine its spending levels. Government revenue can be increased through improved tax compliance and efficiency in revenue collection, maximizing revenue from mineral and other natural resources, and increasing tax rates where appropriate. The emphasis should be on increasing revenue through the most progressive means possible; the purpose of raising government spending on health would be defeated if that spending were funded by increasing the relative tax burden of those who are meant to benefit. Increasing government revenue through taxation or other sources is first and foremost a fiscal policy choice or political decision and should be supported through concerted global action.

  11. Supply of domestic hot Water at comfortable temperatures by low-temperature district heating without risk of Legionella

    DEFF Research Database (Denmark)

    Yang, Xiaochen

    disinfection efficacy for Legionella if supplied by LTDH, and inject no additives into the water. Thus, they can be considered as feasible sterilization solutions. In terms of the DHW system design methods, in addition to ensure the safe and hygiene DHW supply, the potential DHW systems should also...... temperature for space heating but lower than LTDH. Therefore, to meet the comfort and hygiene requirements for DHW supply, supplementary heating methods should be combined. However, one obstacle to realize the LTDH/ULTDH is the concern of the violation of the comfort and hygiene requirements of DHW supply....... According to the Danish standard, the supply for DHW should be able to reach 45 °C for the kitchen use and 40 °C for other uses for comfort. Regarding to the hygiene requirements, large DHW system with DHW storage tank and circulation has to use high temperature regime to get rid of Legionella. The storage...

  12. Heat-pipe transient model for space applications

    International Nuclear Information System (INIS)

    Tournier, J.; El-Genk, M.S.; Juhasz, A.J.

    1991-01-01

    A two-dimensional model is developed for simulating heat pipes transient performance following changes in the input/rejection power or in the evaporator/condenser temperatures. The model employs the complete form of governing equations and momentum and energy jump conditions at the liquid-vapor interface. Although the model is capable of handling both cylindrical and rectangular geometries, the results reported are for a circular heat pipe with liquid lithium as the working fluid. The model incorporates a variety of other working fluids, such as water, ammonia, potassium, sodium, and mercury, and offers combinations of isothermal, isoflux, convective and radiative heating/cooling conditions in the evaporator and condenser regions of the heat pipe. Results presented are for lithium heat pipes with exponential heating of the evaporator and isothermal cooling of the condenser

  13. Heat receivers for solar dynamic space power systems

    Science.gov (United States)

    Perez-Davis, Marla Esther

    A review of state-of-the-art technology is presented and discussed for phase change materials. Some of the advanced solar dynamic designs developed as part of the Advanced Heat Receiver Conceptual Design Study performed for LeRC are discussed. The heat receivers are analyzed and several recommendations are proposed, including two new concepts. The first concept evaluated the effect of tube geometries inside the heat receiver. It was found that a triangular configuration would provide better heat transfer to the working fluid, although not necessarily with a reduction in receiver size. A sensible heat receiver considered in this study uses vapor grown graphite fiber-carbon (VGCF/C) composite as the thermal storage media and was designed for a 7 kW Brayton engine. The proposed heat receiver stores the required energy to power the system during eclipse in the VGCF/C composite. The heat receiver analysis was conducted through the Systems Improved Numerical Differencing Analyzer and Fluid Integrator (SINDA) software package. The proposed heat receiver compares well with other latent and advanced sensible heat receivers while avoiding the problems associated with latent heat storage salts and liquid metal heat pipes. The weight and size of the system can be optimized by changes in geometry and technology advances for this new material. In addition to the new concepts, the effect of atomic oxygen on several materials is reviewed. A test was conducted for atomic oxygen attack on boron nitride, which experienced a negligible mass loss when exposed to an atomic oxygen fluence of 5 x 10 exp 21 atoms/sq cm. This material could be used to substitute the graphite aperture plate of the heat receiver.

  14. On variations of space-heating energy use in office buildings

    International Nuclear Information System (INIS)

    Lin, Hung-Wen; Hong, Tianzhen

    2013-01-01

    Highlights: • Space heating is the largest energy end use in the U.S. building sector. • A key design and operational parameters have the most influence on space heating. • Simulated results were benchmarked against actual results to analyze discrepancies. • Yearly weather changes have significant impact on space heating energy use. • Findings enable stakeholders to make better decisions on energy efficiency. - Abstract: Space heating is the largest energy end use, consuming more than seven quintillion joules of site energy annually in the U.S. building sector. A few recent studies showed discrepancies in simulated space-heating energy use among different building energy modeling programs, and the simulated results are suspected to be underpredicting reality. While various uncertainties are associated with building simulations, especially when simulations are performed by different modelers using different simulation programs for buildings with different configurations, it is crucial to identify and evaluate key driving factors to space-heating energy use in order to support the design and operation of low-energy buildings. In this study, 10 design and operation parameters for space-heating systems of two prototypical office buildings in each of three U.S. heating climates are identified and evaluated, using building simulations with EnergyPlus, to determine the most influential parameters and their impacts on variations of space-heating energy use. The influence of annual weather change on space-heating energy is also investigated using 30-year actual weather data. The simulated space-heating energy use is further benchmarked against those from similar actual office buildings in two U.S. commercial-building databases to better understand the discrepancies between simulated and actual energy use. In summary, variations of both the simulated and actual space-heating energy use of office buildings in all three heating climates can be very large. However

  15. Solar space and water heating system installed at Charlottesville, Virginia

    Science.gov (United States)

    1980-01-01

    The solar energy system located at David C. Wilson Neuropsychiatric Hospital, Charlottesville, Virginia, is described. The solar energy system consists of 88 single glazed, Sunworks 'Solector' copper base plate collector modules, hot water coils in the hot air ducts, a Domestic Hot Water (DHW) preheat tank, a 3,000 gallon concrete urethane insulated storage tank and other miscellaneous components. Extracts from the site files, specifications, drawings, installation, operation and maintenance instructions are included.

  16. Competition in the market for space heating. District heating as the infrastructure for competition among fuels and technologies

    International Nuclear Information System (INIS)

    Grohnheit, Poul Erik; Gram Mortensen, Bent Ole

    2003-01-01

    None of the EU directives on liberalisation of the electricity and gas markets are considering the district heating systems, although the district heating networks offer the possibility of competition between natural gas and a range of other fuels on the market for space heating. Cogeneration of electricity and heat for industrial processes or district heating is a technology option for increased energy efficiency and thus reduction of CO 2 emissions. In the mid-1990s less than 10% of the electricity generation in the European Union was combined production with significant variations among Member States. These variations are explained by different national legislation and relative power of institutions, rather than difference in industrial structure, climate or urban physical structure. The 'single energy carrier' directives have provisions that support the development of combined heat and power (CHP), but they do not support the development and expansion of the district heating infrastructure. The article is partly based on a contribution to the Shared Analysis Project for the European Commission DG Energy, concerning the penetration of CHP, energy saving, and renewables as instruments to meet the targets of the Kyoto Protocol within the liberalised European energy market. The quantitative and legal differences of the heat markets in selected Member States are described, and the consequences of the directives are discussed. Finally, we summarise the tasks for a European policy concerning the future regulation of district heating networks for CHP, emphasising the need for rules for a fair competition between natural gas and district heating networks

  17. Heat-pipe development for the SPAR space-power system

    International Nuclear Information System (INIS)

    Ranken, W.A.

    1981-01-01

    The SPAR space power system design is based on a high temperature fast spectrum nuclear reactor that furnishes heat to a thermoelectric conversion system to generate an electrical power output of 100 kW/sub (e)/. An important feature of this design is the use of alkali metal heat pipes to provide redundant, reliable, and low-loss heat transfer at high temperature. Three sets of heat pipes are used in the system. These include sodium/molybdenum heat pipes to transfer heat from the reactor core to the conversion system, potassium/niobium heat pipes to couple the conversion system to the radiator in a redundant manner, and potassium/titanium heat pipes to distribute rejected heat throughout the radiator surface. The designs of these units are discussed and fabrication methods and testing results are described. 12 figures

  18. Utes for space heating and cooling in North Africa

    International Nuclear Information System (INIS)

    Nordell, B.; Grein, M. a.

    2006-01-01

    The North Africa climate is dry and warm with annual mean temperature from 15 degree centigrade to 25 degree centigrade, with a temperature difference of 20 degree centigrade between the coldest and warmest month. Heating is needed during the short winter and there is a large cooling demand during the long summer. Since the undisturbed ground temperature is equal to the annual mean air temperature, the ground is warmer than the air during the winter and colder than air during summer. This is what is required for the direct use of the ground for heating and cooling. In such systems, ground coupled heating and cooling systems, and also in storage systems, Underground Thermal Energy Storage (UTES), some kind of underground duct (PIPE) system is used to inject or extract heat from the ground. Thermal energy is then stored and recovered by heating and cooling of the ground, while the ducts are the heat exchangers with the system. The duct system could be placed horizontally or vertically (e.g. in boreholes) in the ground. In many cases heat pumps or cooling machines are included in the systems but in favourable cases, such as in the North African climate, the ground can be used directly for heating and cooling. then, only a circulation pump is used to pump water through the underground duct system with high efficiencies. Such systems can also be used for thermal energy storage, during shorter periods (diurnal) or even between the seasons. In September 2005 Sebha University and Luleu University of Technology started a Libyan Swedish collaboration to develop and implement these systems for the North African climate. Sweden has considerable experience in ground coupled systems, theoretically and practically, and there are presently more than 300.000 systems in operation in Sweden, mainly for heating. Most of these are small-scale heating systems for singe-family houses but during the last decade several hundred large-scale systems have been built for heating and cooling of

  19. Launching Latin America: International and Domestic Factors in National Space Programs

    Science.gov (United States)

    2014-12-01

    through the Ministério da Defesa (Ministry of Defense [MD]) and the Ministério da Ciência, Tecnologia e Inovação (Ministry of Science, Technology, and...Space Activities: 2005–2014] (Brasília, Brazil: Ministério da Ciência e Tecnologia , 2005), 109. 55 Agência Espacial Brasileira, “Política Espacial...Space Policy],” accessed September 24, 2014, http://www.aeb.gov.br/programa-espacial/politica-espacial/. 56 Ministério da Ciência, Tecnologia e Inovação

  20. Demonstration test on the heat pump system, thermally utilizing the domestic waste water. Result of the collecting test on an air conditioning system, Hokkaido Electric Power Gymnasium, Tomari; Seikatsu haisui netsuriyo heat pump system jissho shiken. Tomari Hokuden taiikukan reidanbo system no sainetsu shiken kekka ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Honma, T; Yamada, K; Watanabe, K [Hokkaido Electric Power Co. Inc., Sapporo (Japan)

    1995-06-14

    A heat pump system utilizing the domestic waste water was introduced into a gymnasium owned by Hokkaido Electric Power to elucidate the applicability of domestic waste water as a thermal source of heat pump in the cold region. The gymnasium is a two-storied concrete building with the floor space of 2292m{sup 2}. Ground water at temperatures from 10 to 20{degree}C is utilized for the water supply. Made to flow together as waste water, the dirty water and daily exhaust water are discharged at the rate of 100t/day into a river after passing through the septic tank. Higher by 5 to 15{degree}C than the atmospheric temperature, the discharging temperature is kept higher than 10{degree}C even during the very cold period. The domestic waste water is almost neutral in pH, and normal in both SS and BOD. The heat pump was utilized for two stages, i.e., thermal collection and temperature heightening. The capacity of a sewage storage tank tank was made to be 170m{sup 3} to meet the thermal load of 139000kcal/h in the gymnasium. The temperature of 15{degree}C could be kept during the air heating trial. The system is about 2 in coefficient of performance. The K-value of heat exchanger decreased by about 30% after seven months of operation. Upon its overhauling, its K-value recovered to 2.37, so that it must be overhauled once a year. 5 refs., 15 figs. 4 tabs.

  1. Decreasing of energy consumption for space heating in existing residential buildings; Combined geothermal and gas district heating systems

    International Nuclear Information System (INIS)

    Rosca, Marcel

    2000-01-01

    The City of Oradea, Romania, has a population of about 230 000 inhabitants. Almost 70% of the total heat demand, including industrial, is supplied by a classical East European type district heating system. The heat is supplied by two low grade coal fired co-generation power plants. The oldest distribution networks and substitutions, as well as one power plant, are 35 years old and require renovation or even reconstruction. The geothermal reservoir located under the city supplies at present 2,2% of the total heat demand. By generalizing the reinjection, the production can be increased to supply about 8% of the total heat demand, without any significant reservoir pressure or temperature decline over 25 years. Another potential energy source is natural gas, a main transport pipeline running close to the city. Two possible scenarios are envisaged to replace the low grade coal by natural gas and geothermal energy as heat sources for Oradea. In one scenario, the geothermal energy supplies the heat for tap water heating and the base load for space heating in a limited number of substations, with peak load being produced by natural gas fired boilers. In the other scenario, the geothermal energy is only used for tap water heating. In both scenarios, all substations are converted into heat plants, natural gas being the main energy source. The technical, economic, and environmental assessment of the two proposed scenarios are compared with each other, as well as with the existing district heating system. Two other possible options, namely to renovate and convert the existing co-generation power plants to natural gas fired boilers or to gas turbines, are only briefly discussed, being considered unrealistic, at least for the short and medium term future. (Author)

  2. Residential and commercial space heating and cooling with possible greenhouse operation; Baca Grande development, San Luis Valley, Colorado. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Goering, S.W.; Garing, K.L.; Coury, G.E.; Fritzler, E.A.

    1980-05-01

    A feasibility study was performed to evaluate the potential of multipurpose applications of moderate-temperature geothermal waters in the vicinity of the Baca Grande community development in the San Luis Valley, Colorado. The project resource assessment, based on a thorough review of existing data, indicates that a substantial resource likely exists in the Baca Grande region capable of supporting residential and light industrial activity. Engineering designs were developed for geothermal district heating systems for space heating and domestic hot water heating for residences, including a mobile home park, an existing motel, a greenhouse complex, and other small commercial uses such as aquaculture. In addition, a thorough institutional analysis of the study area was performed to highlight factors which might pose barriers to the ultimate commercial development of the resource. Finally, an environmental evaluation of the possible impacts of the proposed action was also performed. The feasibility evaluation indicates the economics of the residential areas are dependent on the continued rate of housing construction. If essentially complete development could occur over a 30-year period, the economics are favorable as compared to existing alternatives. For the commercial area, the economics are good as compared to existing conventional energy sources. This is especially true as related to proposed greenhouse operations. The institutional and environmental analyses indicates that no significant barriers to development are apparent.

  3. Solar Energy Gain and Space-Heating Energy Supply Analyses for Solid-Wall Dwelling Retrofitted with the Experimentally Achievable U-value of Novel Triple Vacuum Glazing

    Directory of Open Access Journals (Sweden)

    Saim Memon

    2017-06-01

    Full Text Available A considerable effort is devoted to devising retrofit solutions for reducing space-heating energy in the domestic sector. Existing UK solid-wall dwellings, which have both heritage values and historic fabric, are being improved but they tend to have meagre thermal performance, partly, due to the heat-loss through glazings. This paper takes comparative analyses approach to envisage space-heating supply required in order to maintain thermal comfort temperatures and attainable solar energy gains to households with the retrofit of an experimentally achievable thermal performance of the fabricated sample of triple vacuum glazing to a UK solid-wall dwelling. 3D dynamic thermal models (timely regimes of heating, occupancy, ventilation and internal heat gains of an externally-insulated solid-wall detached dwelling with a range of existing glazing types along with triple vacuum glazings are modelled. A dramatic decrease of space-heating load and moderate increase of solar gains are resulted with the dwelling of newly achievable triple vacuum glazings (having centre-of-pane U-value of 0.33 Wm-2K-1 compared to conventional glazing types. The space-heating annual cost of single glazed dwellings was minimised to 15.31% (≈USD 90.7 with the retrofit of triple-vacuum glazings. An influence of total heat-loss through the fabric of solid-wall dwelling was analysed with steady-state calculations which indicates a fall of 10.23 % with triple vacuum glazings compared to single glazings.

  4. Hybrid PV and solar-thermal systems for domestic heat and power provision in the UK: Techno-economic considerations

    International Nuclear Information System (INIS)

    Herrando, María; Markides, Christos N.

    2016-01-01

    considering the economic aspects of PVT technology, based on which invaluable policy-related conclusions can be drawn concerning the incentives that would need to be in place to accelerate the widespread uptake of such systems. It is found that, with an electricity-only Feed-In Tariff (FIT) support rate at 43.3 p/kW h over 20 years, the system cost estimates of optimised PVT/w systems have an 11.2-year discounted payback period (PV-only: 6.8 years). The role and impact of heat-based incentives is also studied. The implementation of a domestic Renewable Heat Incentive (RHI) at a rate of 8.5 p/kW h in quarterly payments leads to a payback reduction of about 1 year. If this incentive is given as a one-off voucher at the beginning of the system’s lifetime, the payback is reduced by about 2 years. With a RHI rate of 20 p/kW h (about half of the FIT rate) PVT technology would have approximately the same payback as PV. It is concluded that, if primary energy (currently dominated by fossil fuels) and CO_2 emission minimisation are important goals of national energy policy, PVT systems offer a significantly improved proposition over equivalent PV-only systems, but at an elevated cost. This is in need of careful reflection when developing relevant policy and considering technology incentivation. Currently, although heat outweighs electricity consumption by a factor of about 4 (by energy unit) in the UK domestic sector, the support landscape has strongly favoured electrical microgeneration, being inclined in favour of PV technology, which has been experiencing a well-documented exponential growth over recent decades.

  5. Should the Red Dragon arise? Assessing China's options vis-à-vis the enactment of a domestic space resources utilization law

    Science.gov (United States)

    Hao, L.; Tronchetti, F.

    2017-05-01

    The past couple of years have witnesses one of the most exciting, yet controversial, developments in the field of space law, namely the adoption of domestic laws authorizing the (private) appropriation and utilization of outer space resources. Even though the technology to effectively mine resources in outer space is still under development countries like the United States and Luxembourg have taken this legislative step as a mean to promote the growth of a domestic private space mining sector. The enactment of national space resources utilization laws has generated extensive interest both within academic circles and official fora, such as the United Nations Committee on the Peaceful Uses of Outer Space (UNCOPUOS). In this context, several countries have expressed their opinion about these initiatives, by often criticizing their legality vis-a-vis international space law. Despite this remarkable level of interest there is a country that throughout this process has maintained a low profile, namely China. Indeed, China has neither reacted to the US and Luxembourgish moves nor has officially commented on the lawfulness of domestic space mining laws. This conduct is particularly relevant not only in the light of the growing importance of the Chinese space program but also if one considers that China is the country most involved in the exploration and study of celestial bodies and their resources, particularly the Moon. For this reasons it would have been legitimate to expect China to have a more engaged behavior. However, China has acted otherwise. It seems thus worth evaluating whether China should maintain this 'wait and see' approach or should instead switch towards a more assertive position, both internationally and domestically, especially one which includes the adoption of a space resources utilization act.

  6. ZrH reactor lattice spacing (heat transfer considerations)

    International Nuclear Information System (INIS)

    Felten, L.D.

    1970-01-01

    Temperature calculations for a 295 element ZrH reactor at fuel element spacings from 0.010'' to 0.065'' showed a very small dependence of reactor temperature on element spacing. It was found that one variation in coolant channel area (2 zones) was sufficient to satisfactorily shape the radial flow profile for the core. (U.S.)

  7. Linear programming control of a group of heat pumps

    NARCIS (Netherlands)

    Fink, J.; van Leeuwen, Richard Pieter; Hurink, Johann L.; Smit, Gerardus Johannes Maria

    2015-01-01

    For a new district in the Dutch city Meppel, a hybrid energy concept is developed based on bio-gas co-generation. The generated electricity is used to power domestic heat pumps which supply thermal energy for domestic hot water and space heating demand of households. In this paper, we investigate

  8. Design package for a complete residential solar space heating and hot water system

    Science.gov (United States)

    1978-01-01

    Information necessary to evaluate the design of a solar space heating and hot water system is reported. System performance specifications, the design data brochure, the system description, and other information pertaining to the design are included.

  9. Lunar Heat Flux Measurements Enabled by a Microwave Radiometer Aboard the Deep Space Gateway

    Science.gov (United States)

    Siegler, M.; Ruf, C.; Putzig, N.; Morgan, G.; Hayne, P.; Paige, D.; Nagihara, S.; Weber, R.

    2018-02-01

    We would like to present a concept to use the Deep Space Gateway as a platform for constraining the geothermal heat production, surface, and near-surface rocks, and dielectric properties of the Moon from orbit with passive microwave radiometery.

  10. Performance predictions and measurements for space-power-system heat pipes

    International Nuclear Information System (INIS)

    Prenger, F.C. Jr.

    1981-01-01

    High temperature liquid metal heat pipes designed for space power systems have been analyzed and tested. Three wick designs are discussed and a design rationale for the heat pipe is provided. Test results on a molybdenum, annular wick heat pipe are presented. Performance limitations due to boiling and capillary limits are presented. There is evidence that the vapor flow in the adiabatic section is turbulent and that the transition Reynolds number is 4000

  11. Exergy analysis of a two-stage ground source heat pump with a vertical bore for residential space conditioning under simulated occupancy

    International Nuclear Information System (INIS)

    Ally, Moonis R.; Munk, Jeffrey D.; Baxter, Van D.; Gehl, Anthony C.

    2015-01-01

    Highlights: • Exergy and energy analysis of a vertical-bore ground source heat pump over a 12-month period is presented. • The ground provided more than 75% of the heating energy. • Performance metrics are presented. • Sources of systemic inefficiency are identified and prioritized using Exergy analysis. • Understanding performance metrics is vital for judicial use of renewable energy. - Abstract: This twelve-month field study analyzes the performance of a 7.56 W (2.16-ton) water-to-air-ground source heat pump (WA-GSHP) to satisfy domestic space conditioning loads in a 253 m 2 house in a mixed-humid climate in the United States. The practical feasibility of using the ground as a source of renewable energy is clearly demonstrated. Better than 75% of the energy needed for space heating was extracted from the ground. The average monthly electricity consumption for space conditioning was only 40 kW h at summer and winter thermostat set points of 24.4 °C and 21.7 °C, respectively. The WA-GSHP shared the same 94.5 m vertical bore ground loop with a separate water-to-water ground-source heat pump (WW-GSHP) for meeting domestic hot water needs in the same house. Sources of systemic irreversibility, the main cause of lost work, are identified using Exergy and energy analysis. Quantifying the sources of Exergy and energy losses is essential for further systemic improvements. The research findings suggest that the WA-GSHPs are a practical and viable technology to reduce primary energy consumption and greenhouse gas emissions under the IECC 2012 Standard, as well as the European Union (EU) 2020 targets of using renewable energy resources

  12. Solar thermal heating and cooling. A bibliography with abstracts

    Science.gov (United States)

    Arenson, M.

    1979-01-01

    This bibliographic series cites and abstracts the literature and technical papers on the heating and cooling of buildings with solar thermal energy. Over 650 citations are arranged in the following categories: space heating and cooling systems; space heating and cooling models; building energy conservation; architectural considerations, thermal load computations; thermal load measurements, domestic hot water, solar and atmospheric radiation, swimming pools; and economics.

  13. Optimal selection among different domestic energy consumption patterns based on energy and exergy analysis

    International Nuclear Information System (INIS)

    Lu, S.; Wu, J.Y.

    2010-01-01

    In China market, people have many choices for air conditioning of their apartments, including heat-pump systems or gas-fired boilers for heating and air conditioners for cooling. Domestic hot water is usually provided by domestic water heaters making use of electricity or natural gas, which are known for their great energy costs. These systems consume much energy and increase the total cost of required domestic energy. A novel system combining heat pump with water heater is proposed in this paper, and it is named domestic energy system. The system can realize the provision of space heating, cooling and domestic hot water throughout a year. Based on different types of air conditioners, space heating equipments and water heaters, domestic energy consumption patterns are concluded to be eight categories. This study describes and compares the eight domestic energy consumption patterns by economic analysis and prime energy analysis method. Results show that the domestic energy system can provide good economy and save energy significantly. Furthermore, exergy analysis method is employed to compare the exergy efficiencies of different energy consumption systems. The results show that the domestic energy system has the highest energy conversion efficiency and can make remarkable contribution to social energy saving.

  14. Sustainability in the UK domestic sector : A review and analysis of the sustainable energy innovations available to homeowners

    OpenAIRE

    Hultgren, Elin

    2015-01-01

    The UK Government has set an ambitious legislative goal of reducing greenhouse gas emissions by 80 % by 2050. Of the total energy used in the UK, 31 % is used in the domestic sector. In the domestic sector energy is used for space and hot water heating, lighting, appliances and cooking. Space and hot water heating make up 82 % of the total energy used in the UK domestic sector. Almost all of the energy used in the UK domestic sector originates from depletable resources. In order for the UK to...

  15. Evaluation of Advanced Models for PAFS Condensation Heat Transfer in SPACE Code

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Byoung-Uhn; Kim, Seok; Park, Yu-Sun; Kang, Kyung Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Ahn, Tae-Hwan; Yun, Byong-Jo [Pusan National University, Busan (Korea, Republic of)

    2015-10-15

    The PAFS (Passive Auxiliary Feedwater System) is operated by the natural circulation to remove the core decay heat through the PCHX (Passive Condensation Heat Exchanger) which is composed of the nearly horizontal tubes. For validation of the cooling and operational performance of the PAFS, PASCAL (PAFS Condensing Heat Removal Assessment Loop) facility was constructed and the condensation heat transfer and natural convection phenomena in the PAFS was experimentally investigated at KAERI (Korea Atomic Energy Research Institute). From the PASCAL experimental result, it was found that conventional system analysis code underestimated the condensation heat transfer. In this study, advanced condensation heat transfer models which can treat the heat transfer mechanisms with the different flow regimes in the nearly horizontal heat exchanger tube were analyzed. The models were implemented in a thermal hydraulic safety analysis code, SPACE (Safety and Performance Analysis Code for Nuclear Power Plant), and it was evaluated with the PASCAL experimental data. With an aim of enhancing the prediction capability for the condensation phenomenon inside the PCHX tube of the PAFS, advanced models for the condensation heat transfer were implemented into the wall condensation model of the SPACE code, so that the PASCAL experimental result was utilized to validate the condensation models. Calculation results showed that the improved model for the condensation heat transfer coefficient enhanced the prediction capability of the SPACE code. This result confirms that the mechanistic modeling for the film condensation in the steam phase and the convection in the condensate liquid contributed to enhance the prediction capability of the wall condensation model of the SPACE code and reduce conservatism in prediction of condensation heat transfer.

  16. Investigation and assessment of wall heat transfer correlations in SPACE code

    International Nuclear Information System (INIS)

    Kim, Jung Woo; Kim, Kyung Doo; Moon, Sang Ki; Choi, Ki Yong; Park, Hyun Sik

    2010-06-01

    SPACE, which is a safety analysis code for nuclear power plants, has been developed to analyze the multidimensional, two-component and three-field flow. This code can be applied to safety analysis for approval which is thermal-hydraulic analysis to support the nuclear power station design, establishment of accident ease strategy, development of operating guide line, experiment plan and analysis. To do so, SPACE code has 12 wall heat transfer mode and the corresponding models and correlations to deal with the physical heat transfer phenomenon in wall surface. In this report, the physical correlation models regarding the wall heat transfer are explained and their performance is assessed against several SET

  17. Industrial food processing and space heating with geothermal heat. Final report, February 16, 1979-August 31, 1982

    Energy Technology Data Exchange (ETDEWEB)

    Kunze, J.F.; Marlor, J.K.

    1982-08-01

    A competitive aware for a cost sharing program was made to Madison County, Idaho to share in a program to develop moderate-to-low temperature geothermal energy for the heating of a large junior college, business building, public shcools and other large buildings in Rexburg, Idaho. A 3943 ft deep well was drilled at the edge of Rexburg in a region that had been probed by some shallower test holes. Temperatures measured near the 4000 ft depth were far below what was expected or needed, and drilling was abandoned at that depth. In 1981 attempts were made to restrict downward circulation into the well, but the results of this effort yielded no higher temperatures. The well is a prolific producer of 70/sup 0/F water, and could be used as a domestic water well.

  18. Solar power from the supermarket. Water heating, space heating and air conditioning with solar collectors

    Energy Technology Data Exchange (ETDEWEB)

    1976-08-01

    The different ways of utilizing solar energy are discussed. So far, top water heating is still the most practicable and most economical solution. Model houses with solar collectors, built by BBC and Philips, are dealt with in particular.

  19. Solar-assisted heat pump system for cost-effective space heating and cooling

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, J W; Kush, E A; Metz, P D

    1978-03-01

    The use of heat pumps for the utilization of solar energy is studied. Two requirements for a cost-effective system are identified: (1) a special heat pump whose coefficient of performance continues to rise with source temperature over the entire range appropriate for solar assist, and (2) a low-cost collection and storage subsystem able to supply solar energy to the heat pump efficiently at low temperatures. Programs leading to the development of these components are discussed. A solar assisted heat pump system using these components is simulated via a computer, and the results of the simulation are used as the basis for a cost comparison of the proposed system with other solar and conventional systems.

  20. Thin film heat flux sensor for Space Shuttle Main Engine turbine environment

    Science.gov (United States)

    Will, Herbert

    1991-01-01

    The Space Shuttle Main Engine (SSME) turbine environment stresses engine components to their design limits and beyond. The extremely high temperatures and rapid temperature cycling can easily cause parts to fail if they are not properly designed. Thin film heat flux sensors can provide heat loading information with almost no disturbance of gas flows or of the blade. These sensors can provide steady state and transient heat flux information. A thin film heat flux sensor is described which makes it easier to measure small temperature differences across very thin insulating layers.

  1. Optimizing a Small Ammonia Heat Pump with Accumulator Tank for Space and Hot Tap Water Heating

    OpenAIRE

    Lalovs, Arturs

    2015-01-01

    The heat pump market offers a wide variety of different residential heat pumps where most of them utilize refrigerant R-410A which has high global warming potential. Considering the fact that global policy starts to focus on issues related to energy efficiency and harmful impact to the environment, it is necessary to investigate over new refrigerants. As an alternative solution is to utilize natural refrigerants, such as ammonia, which has almost zero glob...

  2. Accident analysis of heat pipe cooled and AMTEC conversion space reactor system

    International Nuclear Information System (INIS)

    Yuan, Yuan; Shan, Jianqiang; Zhang, Bin; Gou, Junli; Bo, Zhang; Lu, Tianyu; Ge, Li; Yang, Zijiang

    2016-01-01

    Highlights: • A transient analysis code TAPIRS for HPS has been developed. • Three typical accidents are analyzed using TAPIRS. • The reactor system has the self-stabilization ability under accident conditions. - Abstract: A space power with high power density, light weight, low cost and high reliability is of crucial importance to future exploration of deep space. Space reactor is an excellent candidate because of its unique characteristics of high specific power, low cost, strong environment adaptability and so on. Among all types of space reactors, heat pipe cooled space reactor, which adopts the passive heat pipe (HP) as core cooling component, is considered as one of the most promising choices and is widely studied all over the world. This paper develops a transient analysis code (TAPIRS) for heat pipe cooled space reactor power system (HPS) based on point reactor kinetics model, lumped parameter core heat transfer model, combined HP model (self-diffusion model, flat-front startup model and network model), energy conversion model of Alkali Metal Thermal-to-Electric Conversion units (AMTEC), and HP radiator model. Three typical accidents, i.e., control drum failure, AMTEC failure and partial loss of the heat transfer area of radiator are then analyzed using TAPIRS. By comparing the simulation results of the models and steady state with those in the references, the rationality of the models and the solution method is validated. The results show the following. (1) After the failure of one set of control drums, the reactor power finally reaches a stable value after two local peaks under the temperature feedback. The fuel temperature rises rapidly, however it is still under safe limit. (2) The fuel temperature is below a safe limit under the AMTEC failure and partial loss of the heat transfer area of radiator. This demonstrates the rationality of the system design and the potential applicability of the TAPIRS code for the future engineering application of

  3. Optimal wall spacing for heat transport in thermal convection

    Energy Technology Data Exchange (ETDEWEB)

    Shishkina, Olga [Max Planck Institute for Dynamics and Self-Organization, Goettingen (Germany)

    2016-11-01

    The simulation of RB flow for Ra up to 1 x 10{sup 10} is computationally expensive in terms of computing power and hard disk storage. Thus, we gratefully acknowledge the computational resources supported by Leibniz-Rechenzentrum Munich. Compared to Γ=1 situation, a new physical picture of heat transport is identified here at Γ{sub opt} for any explored Ra. Therefore, a detailed comparison between Γ=1 and Γ=Γ{sub opt} is valuable for our further research, for example, their vertical temperature and velocity profiles. Additionally, we plan to compare the fluid with different Pr under geometrical confinement, which are computationally expensive for the situations of Pr<<1 and Pr>>1.

  4. Welding iridium heat-source capsules for space missions

    International Nuclear Information System (INIS)

    Kanne, W.R. Jr.

    1982-03-01

    A remote computer-controlled welding station was developed to encapsulate radioactive PuO 2 in iridium. Weld quench cracking caused an interruption in production of capsules for upcoming space missions. Hot crack sensitivity of the DOP-26 iridium alloy was associated with low melting constituents in the grain boundaries. The extent of cracking was reduced but could not be eliminated by changes to the welding operation. An ultrasonic test was developed to detect underbead cracks exceeding a threshold size. Production was continued using the ultrasonic test to reject capsules with detectable cracks

  5. Quantification of emissions from domestic heating in residential areas of İzmir, Turkey and assessment of the impact on local/regional air-quality

    Energy Technology Data Exchange (ETDEWEB)

    Sari, Deniz, E-mail: deniz.sari@tubitak.gov.tr [TUBITAK Marmara Research Center, Environment and Cleaner Production Institute, 41470 Kocaeli (Turkey); Bayram, Abdurrahman [Department of Environmental Engineering, Faculty of Engineering, Dokuz Eylul University, Kaynaklar Campus, 35160 Buca, Izmir (Turkey)

    2014-08-01

    Air pollution in cities is a major environmental problem principally in the developing countries. The quantification of emissions is a basic requirement to assess the human influence to the atmosphere. The air quality generally shows decreases with the major contribution residential emissions and meteorology in the winter season in the big cities. Poor meteorological conditions especially inversion events for the efficient mixing of air pollutants occurred during the winter months in İzmir. With this work we quantify the amount of domestic heating emissions for particulate matter (PM10), sulfur dioxides (SO{sub 2}), nitrogen dioxides (NO{sub 2}), volatile organic compounds (VOC) and carbon monoxide (CO) together with greenhouse gases which are carbon dioxide (CO{sub 2}), nitrous oxide (N{sub 2}O) and methane (CH{sub 4}) in İzmir for 2008–2009 winter season. The results showed that the most affected residential areas were central districts in the city center from domestic heating emissions due to meteorological condition and demographic reasons. Air quality modeling is a great tool for assisting policy makers how to decrease emissions and improve air quality. At the second part of the study, calculated emissions were modeled by using CALMET/CALPUFF dispersion modeling system and plotted in the form of air pollution maps by using geographical information system to determine the locations and estimate the effects of the new residential areas that will be established in the future in İzmir. - Highlights: • The air pollution in cities especially shows raises with the opening of winter season. • Air pollution has become a problem due to rapid urbanization in İzmir, Turkey. • The air quality shows decreases with the residential emissions in İzmir's winter. • With this work we quantify the amount of domestic heating emissions for pollutants. • The impact of emissions on local air-quality is determined by using dispersion model.

  6. Quantification of emissions from domestic heating in residential areas of İzmir, Turkey and assessment of the impact on local/regional air-quality

    International Nuclear Information System (INIS)

    Sari, Deniz; Bayram, Abdurrahman

    2014-01-01

    Air pollution in cities is a major environmental problem principally in the developing countries. The quantification of emissions is a basic requirement to assess the human influence to the atmosphere. The air quality generally shows decreases with the major contribution residential emissions and meteorology in the winter season in the big cities. Poor meteorological conditions especially inversion events for the efficient mixing of air pollutants occurred during the winter months in İzmir. With this work we quantify the amount of domestic heating emissions for particulate matter (PM10), sulfur dioxides (SO 2 ), nitrogen dioxides (NO 2 ), volatile organic compounds (VOC) and carbon monoxide (CO) together with greenhouse gases which are carbon dioxide (CO 2 ), nitrous oxide (N 2 O) and methane (CH 4 ) in İzmir for 2008–2009 winter season. The results showed that the most affected residential areas were central districts in the city center from domestic heating emissions due to meteorological condition and demographic reasons. Air quality modeling is a great tool for assisting policy makers how to decrease emissions and improve air quality. At the second part of the study, calculated emissions were modeled by using CALMET/CALPUFF dispersion modeling system and plotted in the form of air pollution maps by using geographical information system to determine the locations and estimate the effects of the new residential areas that will be established in the future in İzmir. - Highlights: • The air pollution in cities especially shows raises with the opening of winter season. • Air pollution has become a problem due to rapid urbanization in İzmir, Turkey. • The air quality shows decreases with the residential emissions in İzmir's winter. • With this work we quantify the amount of domestic heating emissions for pollutants. • The impact of emissions on local air-quality is determined by using dispersion model

  7. Space heating with ultra-low-temperature district heating - a case study of four single-family houses from the 1980s

    DEFF Research Database (Denmark)

    Østergaard, Dorte Skaarup; Svendsen, Svend

    2017-01-01

    . These benefits can be maximized if district heating temperatures are lowered as much as possible. In this paper we report on a project where 18 Danish single-family houses from the 1980s were supplied by ultra-low temperature district heating with a supply temperature as low as 45 degrees C for the main part...... of the year. The houses were heated by the existing hydraulic radiator systems, while domestic hot water was prepared by use of district heating and electric boosting. This paper evaluated the heating system temperatures that were necessary in order to maintain thermal comfort in four of the houses. First...... the four houses were modelled in the building simulation tool IDA ICE. The simulation models included the actual radiator sizes and the models were used to simulate the expected thermal comfort in the houses and resulting district heating return temperatures. Secondly measurements of the actual district...

  8. Boundary conditions for heat transfer and evaporative cooling in the trachea and air sac system of the domestic fowl: a two-dimensional CFD analysis.

    Directory of Open Access Journals (Sweden)

    Nina S Sverdlova

    Full Text Available Various parts of the respiratory system play an important role in temperature control in birds. We create a simplified computational fluid dynamics (CFD model of heat exchange in the trachea and air sacs of the domestic fowl (Gallus domesticus in order to investigate the boundary conditions for the convective and evaporative cooling in these parts of the respiratory system. The model is based upon published values for respiratory times, pressures and volumes and upon anatomical data for this species, and the calculated heat exchange is compared with experimentally determined values for the domestic fowl and a closely related, wild species. In addition, we studied the trachea histologically to estimate the thickness of the heat transfer barrier and determine the structure and function of moisture-producing glands. In the transient CFD simulation, the airflow in the trachea of a 2-dimensional model is evoked by changing the volume of the simplified air sac. The heat exchange between the respiratory system and the environment is simulated for different ambient temperatures and humidities, and using two different models of evaporation: constant water vapour concentration model and the droplet injection model. According to the histological results, small mucous glands are numerous but discrete serous glands are lacking on the tracheal surface. The amount of water and heat loss in the simulation is comparable with measured respiratory values previously reported. Tracheal temperature control in the avian respiratory system may be used as a model for extinct or rare animals and could have high relevance for explaining how gigantic, long-necked dinosaurs such as sauropoda might have maintained a high metabolic rate.

  9. Critical evaluation of molybdenum and its alloys for use in space reactor core heat pipes

    International Nuclear Information System (INIS)

    Lundberg, L.B.

    1981-01-01

    The choice of pure molybdenum as the prime candidate material for space reactor core heat pipes is examined, and the advantages and disadvantages of this material are brought into focus. Even though pure molybdenum heat pipes have been built and tested, this metal's high ductile-brittle transition temperature and modest creep strength place significant design restrictions on a core heat pipe made from it. Molybdenum alloys are examined with regard to their promise as potential replacements for pure molybdenum. The properties of TZM and molybdenum-rhenium alloys are examined, and it appears that Mo-Re alloys with 10 to 15 wt % rhenium offer the most advantage as an alternative to pure molybdenum in space reactor core heat pipes

  10. Benefits and well-being perceived by green spaces users during heat waves

    Directory of Open Access Journals (Sweden)

    Dentamaro I

    2010-07-01

    Full Text Available In urban environments, green spaces have proven to act as ameliorating factors of some climatic features related to heat stress, reducing their effects and providing comfortable outdoor settings for people. In addition, green spaces have demonstrated greater capacity, compared with built-up areas, for promoting human health and well-being. In this paper, we present results of a study conducted in Italy with the general goal to contribute to the theoretical and empirical rationale for linking green spaces with well-being in urban environments. Specifically, the study focused on the physical and psychological benefits and the general well-being associated with the use of green spaces on people when heat stress episodes are more likely to occur. A questionnaire was set up and administered to users of selected green spaces in Italy (metropolitan area of Milan and Bari - n=400. Results indicate that longer and frequent visits of green spaces generate significant improvements of the perceived benefits and well-being among users. These results are consistent with the idea that the use of green spaces could alleviate the perception of thermal discomfort during periods of heat stress.

  11. Self-rewetting carbon nanofluid as working fluid for space and terrestrial heat pipes

    International Nuclear Information System (INIS)

    Di Paola, R.; Savino, R.; Mirabile Gattia, D.; Marazzi, R.; Vittori Antisari, M.

    2011-01-01

    Thermal management is very important in modern electronic systems. Recent researches have been dedicated to the study of the heat transfer performances of binary heat transfer fluids with peculiar surface tension properties and in particular to that of “self-rewetting fluids”, i.e., liquids with a surface tension increasing with temperature and concentration. Since in the course of liquid/vapor-phase change, self-rewetting fluids behavior induces a rather strong liquid inflow (caused by both temperature and concentration gradients) from the cold region (where liquid condensates) to the hot evaporator region, this fluids have been proposed and investigated as new heat transfer fluids for advanced heat transfer devices, e.g., heat pipes or heat spreaders for terrestrial and space applications (Savino et al. in Space Technol 25(1):59–61, 2009). The present work is dedicated to the study of the thermophysical properties of a new class of heat transfer fluids based on water/alcohol solutions with suspended carbon nanostructures, in particular single-wall carbon nanohorns (SWNH), synthesized by a homemade apparatus with an AC arc discharge in open air (Mirabile Gattia et al. in Nanotechnology 18:255604, 2007). SWNHs are cone-shaped nanoparticles with diameters between 1 and 5 nm and lengths in the range of 20–100 nm. SWNHs could be found in the form of quite-spherical aggregates with diameters ranging from 20 to 100 nm. The paper also discusses the results of these investigations and laboratory characterization tests of different heat pipes, including reference ordinary heat pipes and innovative pipes filled with self-rewetting fluids and self-rewetting nanofluids. The potential interest of the proposed studies stems from the large number of possible industrial applications, including space technologies and terrestrial applications, such as cooling of electronic components.

  12. Self-rewetting carbon nanofluid as working fluid for space and terrestrial heat pipes

    Science.gov (United States)

    Di Paola, R.; Savino, R.; Mirabile Gattia, D.; Marazzi, R.; Vittori Antisari, M.

    2011-11-01

    Thermal management is very important in modern electronic systems. Recent researches have been dedicated to the study of the heat transfer performances of binary heat transfer fluids with peculiar surface tension properties and in particular to that of "self-rewetting fluids", i.e., liquids with a surface tension increasing with temperature and concentration. Since in the course of liquid/vapor-phase change, self-rewetting fluids behavior induces a rather strong liquid inflow (caused by both temperature and concentration gradients) from the cold region (where liquid condensates) to the hot evaporator region, this fluids have been proposed and investigated as new heat transfer fluids for advanced heat transfer devices, e.g., heat pipes or heat spreaders for terrestrial and space applications (Savino et al. in Space Technol 25(1):59-61, 2009). The present work is dedicated to the study of the thermophysical properties of a new class of heat transfer fluids based on water/alcohol solutions with suspended carbon nanostructures, in particular single-wall carbon nanohorns (SWNH), synthesized by a homemade apparatus with an AC arc discharge in open air (Mirabile Gattia et al. in Nanotechnology 18:255604, 2007). SWNHs are cone-shaped nanoparticles with diameters between 1 and 5 nm and lengths in the range of 20-100 nm. SWNHs could be found in the form of quite-spherical aggregates with diameters ranging from 20 to 100 nm. The paper also discusses the results of these investigations and laboratory characterization tests of different heat pipes, including reference ordinary heat pipes and innovative pipes filled with self-rewetting fluids and self-rewetting nanofluids. The potential interest of the proposed studies stems from the large number of possible industrial applications, including space technologies and terrestrial applications, such as cooling of electronic components.

  13. Heat-electricity convertion systems for a Brazilian space micro nuclear reactor

    Energy Technology Data Exchange (ETDEWEB)

    Guimaraes, Lamartine N.F.; Marcelino, Natalia B.; Placco, Guilherme M.; Nascimento, Jamil A.; Borges, Eduardo M., E-mail: guimarae@ieav.cta.br, E-mail: lamartine.guimaraes@pq.cnpq.br, E-mail: jamil@ieav.cta.br, E-mail: jalnsgf@outlook.com, E-mail: borges.em@hotmail.com, E-mail: ecorborges@hotmail.com, E-mail: ivayolini@gmail.com, E-mail: guilherme_placco@ig.com.br [Instituto de Estudos Avancados (IEAv/DCTA), Sao Jose dos Campos, SP (Brazil); Barrios Junior, Ary Garcia, E-mail: arygarcia89@yahoo.com [Faculdade de Tecnologia Sao Francisco (FATESF), Jacarei, SP (Brazil)

    2013-07-01

    This contribution will discuss the evolution work in the development of thermal cycles to allow the development of heat-electricity conversion for the Brazilian space micro nuclear Reactor. Namely, innovative core and nuclear fuel elements, Brayton cycle, Stirling engine, heat pipes, passive multi-fluid turbine, among others. This work is basically to set up the experimental labs that will allow the specification and design of the space equipment. Also, some discussion of the cost so far, and possible other applications will be presented. (author)

  14. Heat-electricity convertion systems for a Brazilian space micro nuclear reactor

    International Nuclear Information System (INIS)

    Guimaraes, Lamartine N.F.; Marcelino, Natalia B.; Placco, Guilherme M.; Nascimento, Jamil A.; Borges, Eduardo M.; Barrios Junior, Ary Garcia

    2013-01-01

    This contribution will discuss the evolution work in the development of thermal cycles to allow the development of heat-electricity conversion for the Brazilian space micro nuclear Reactor. Namely, innovative core and nuclear fuel elements, Brayton cycle, Stirling engine, heat pipes, passive multi-fluid turbine, among others. This work is basically to set up the experimental labs that will allow the specification and design of the space equipment. Also, some discussion of the cost so far, and possible other applications will be presented. (author)

  15. Experimental Studies on Grooved Double Pipe Heat Exchanger with Different Groove Space

    Science.gov (United States)

    Sunu, P. W.; Arsawan, I. M.; Anakottapary, D. S.; Santosa, I. D. M. C.; Yasa, I. K. A.

    2018-01-01

    Experimental studies were performed on grooved double pipe heat exchanger (DPHE) with different groove space. The objective of this work is to determine optimal heat transfer parameter especially logarithmic mean temperature difference (LMTD). The document in this paper also provides the total heat observed by the cold fluid. The rectangular grooves were incised on outer surface of tube side with circumferential pattern and two different grooves space, namely 1 mm and 2 mm. The distance between grooves and the grooves high were kept constant, 8 mm and 0.3 mm respectively. The tube diameter is 20 mm and its made of aluminium. The shell is made of acrylic which has 28 mm in diameter. Water is used as the working fluid. Using counter flow scheme, the cold fluid flows in the annulus room of DPHE. The volume flowrate of hot fluid remains constant at 15 lpm. The volume flowrate of cold fluid were varied from 11 lpm to 15 lpm. Based on logarithmic mean temperature difference analysis, the LMTD of 1 mm grooves space was higher compared to that of 2 mm grooves space. The smaller grooves space has more advantage since the recirculating region are increased which essentially cause larger heat transfer enhancement.

  16. Dynamic simulation of space heating systems with radiators controlled by TRVs in buildings

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Baoping; Fu, Lin; Di, Hongfa [Department of Building Science, School of Architecture, Tsinghua University, Beijing 100084 (China)

    2008-07-01

    The objective of this paper is to develop a model for simulating the thermal and hydraulic behavior of space heating systems with radiators controlled by thermostat valves (TRVs) in multi-family buildings. This is done by treating the building and the heating system as a complete entity. Sub-models for rooms, radiators, TRVs, and the hydraulic network are derived. Then the suggested sub-models are combined to form an integrated model by considering interactions between them. The proposed model takes into account the heat transfer between neighboring rooms, the transport delay in the radiator, the self-adjusting function of the TRV, and the consumer's regulation behavior, as well as the hydraulic interactions between consumers. To test the model, two space heating systems in Beijing and Tianjin were investigated, and the model was validated under three operation modes. There was good agreement between the measured and simulated values for room temperature, return water temperature, and flow rate. A modeling analysis case was given based on an existing building and heating system. It was found that when the set value of the TRVs were kept on 2-3, about 12.4% reduction of heat consumption could be gained, compared with the situation in which the TRVs were kept fully open. The water flow rate was an important index that truly reflected the heat load change. It was also noted that if the flow rate or supply water temperature changed much during the transport delay time in the radiator, ignoring the transport delay would introduce an obvious deviation of the simulation results. Additionally, when an apartment stopped using the heating system during a heating season, the heat consumption of its neighboring apartments would be increased about 6-14%. (author)

  17. Ultra-Low Heat-Leak, High-Temperature Superconducting Current Leads for Space Applications

    Science.gov (United States)

    Rey, Christopher M.

    2013-01-01

    NASA Goddard Space Flight Center has a need for current leads used in an adiabatic demagnetization refrigerator (ADR) for space applications. These leads must comply with stringent requirements such as a heat leak of approximately 100 W or less while conducting up to 10 A of electric current, from more than 90 K down to 10 K. Additionally, a length constraint of leak leads currently to NASA's specs.

  18. Potential application of glazed transpired collectors to space heating in cold climates

    International Nuclear Information System (INIS)

    Gao, Lixin; Bai, Hua; Mao, Shufeng

    2014-01-01

    Highlights: • A mathematical model for glazed transpired collectors (GTC) is developed. • Glazing results in optical loss, but it decreases convective heat loss effectively. • Thermal performance of GTC shows considerable improvement on flat-plate collectors. • GTC using recirculated air is applicable to space heating in cold climates. - Abstract: Although unglazed transpired collectors (UTC) succeed in industrial ventilation applications, solar fraction is very low when they are used in space heating in cold climates due to the lower exit air temperature. Considering the potential for glazed transpired collectors (GTC) using recirculated air for space heating applications in cold climates, a mathematical model is developed for predicting the thermal performance of GTC. Simulation results show that although glazing results in optical loss, it could decrease convective heat loss resulted from high crosswind velocities effectively. For a solar radiation of 400 W/m 2 , an ambient temperature of −10 °C, and a suction velocity of 0.01 m/s, the exit air temperature of GTC is higher than that of UTC for crosswind velocities exceeding 3.0 m/s. By comparison with a conventional flat-plate solar air collector operating under the same conditions, the thermal performance of GTC shows a significant improvement. For a five-storey hotel building located in the severe cold climate zone of China, case study shows that the annual solar fraction of the GTC-based solar air heating system is about 20%, which is two times higher than that of the flat-plate collector-based system and nearly nine times higher than that of the UTC-based system respectively. Hence, an enormous amount of energy will be saved with the application of GTC to space heating in cold climates

  19. Emission and economic performance assessment of a solid oxide fuel cell micro-combined heat and power system in a domestic building

    International Nuclear Information System (INIS)

    Elmer, Theo; Worall, Mark; Wu, Shenyi; Riffat, Saffa B.

    2015-01-01

    Combined heat and power (CHP) is a promising technological configuration for reducing energy consumption and increasing energy security in the domestic built environment. Fuel cells, on account of their: high electrical efficiency, low emissions and useful heat output have been identified as a key technological option for improving both building energy efficiency and reducing emissions in domestic CHP applications. The work presented in this paper builds upon results currently reported in the literature of fuel cells operating in domestic building applications, with an emission and economic performance assessment of a real, commercially available SOFC mCHP system operating in a real building; under a UK context. This paper aims to assess the emission and economic performance of a commercially available solid oxide fuel cell (SOFC) mCHP system, operating at The University of Nottingham's Creative Energy Homes. The performance assessment evaluates, over a one year period, the associated carbon (emission assessment) and operational costs (economic assessment) of the SOFC mCHP case compared to a ‘base case’ of grid electricity and a highly efficient gas boiler. Results from the annual assessment show that the SOFC mCHP system can generate annual emission reductions of up to 56% and cost reductions of 177% compared to the base case scenario. However support mechanisms such as; electrical export, feed in tariff and export tariff, are required in order to achieve this, the results are significantly less without. A net present value (NPV) analysis shows that the base case is still more profitable over a 15 year period, even though the SOFC mCHP system generates annual revenue; this is on account of the SOFC's high capital cost. In summary, grid interaction and incubator support is essential for significant annual emission and cost reductions compared to a grid electricity and gas boiler scenario. Currently capital cost is the greatest barrier to the economic

  20. Domestic violence

    Science.gov (United States)

    ... violence; Spousal abuse; Elder abuse; Child abuse; Sexual abuse - domestic violence ... 2016. National Domestic Violence Hotline website. What is domestic violence? www.thehotline.org/is-this-abuse/abuse-defined . Accessed July 10, 2016.

  1. Green Space and Deaths Attributable to the Urban Heat Island Effect in Ho Chi Minh City.

    Science.gov (United States)

    Dang, Tran Ngoc; Van, Doan Quang; Kusaka, Hiroyuki; Seposo, Xerxes T; Honda, Yasushi

    2018-04-01

    To quantify heat-related deaths in Ho Chi Minh City, Vietnam, caused by the urban heat island (UHI) and explore factors that may alleviate the impact of UHIs. We estimated district-specific meteorological conditions from 2010 to 2013 using the dynamic downscaling model and calculated the attributable fraction and number of mortalities resulting from the total, extreme, and mild heat in each district. The difference in attributable fraction of total heat between the central and outer districts was classified as the attributable fraction resulting from the UHI. The association among attributable fraction, attributable number with a green space, population density, and budget revenue of each district was then explored. The temperature-mortality relationship between the central and outer areas was almost identical. The attributable fraction resulting from the UHI was 0.42%, which was contributed by the difference in temperature distribution between the 2 areas. Every 1-square-kilometer increase in green space per 1000 people can prevent 7.4 deaths caused by heat. Green space can alleviate the impacts of UHIs, although future studies conducting a heath economic evaluation of tree planting are warranted.

  2. The potential reduction of household space heating CO2 emissions in the Netherlands

    NARCIS (Netherlands)

    Engelmoer, Wiebe

    2011-01-01

    SUMMARY Space heating is responsible for more than half of the total Dutch household energy demand, a large share is based on natural gas. With increasing concern about global warming and depleting gas reserves, energy saving has become an important topi

  3. Capillary-Driven Heat Transfer Experiment: Keeping It Cool in Space

    Science.gov (United States)

    Lekan, Jack F.; Allen, Jeffrey S.

    1998-01-01

    Capillary-pumped loops (CPL's) are devices that are used to transport heat from one location to another--specifically to transfer heat away from something. In low-gravity applications, such as satellites (and possibly the International Space Station), CPL's are used to transfer heat from electrical devices to space radiators. This is accomplished by evaporating one liquid surface on the hot side of the CPL and condensing the vapor produced onto another liquid surface on the cold side. Capillary action, the phenomenon that causes paper towels to absorb spilled liquids, is used to "pump" the liquid back to the evaporating liquid surface (hot side) to complete the "loop." CPL's require no power to operate and can transfer heat over distances as large as 30 ft or more. Their reliance upon evaporation and condensation to transfer heat makes them much more economical in terms of weight than conventional heat transfer systems. Unfortunately, they have proven to be unreliable in space operations, and the explanation for this unreliability has been elusive. The Capillary-Driven Heat Transfer (CHT) experiment is investigating the fundamental fluid physics phenomena thought to be responsible for the failure of CPL's in low-gravity operations. If the failure mechanism can be identified, then appropriate design modifications can be developed to make capillary phase-change heat-transport devices a more viable option in space applications. CHT was conducted onboard the Space Shuttle Columbia during the first Microgravity Science Laboratory (MSL-1) mission, STS-94, which flew from July 1 to 17, 1997. The CHT glovebox investigation, which was conceived by Dr. Kevin Hallinan and Jeffrey Allen of the University of Dayton, focused on studying the dynamics associated with the heating and cooling at the evaporating meniscus within a capillary phase-change device in a low-gravity environment. The CHT experimental hardware was designed by a small team of engineers from Aerospace Design

  4. 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.

  5. The Liquid Droplet Radiator - an Ultralightweight Heat Rejection System for Efficient Energy Conversion in Space

    Science.gov (United States)

    Mattick, A. T.; Hertzberg, A.

    1984-01-01

    A heat rejection system for space is described which uses a recirculating free stream of liquid droplets in place of a solid surface to radiate waste heat. By using sufficiently small droplets ( 100 micron diameter) of low vapor pressure liquids the radiating droplet sheet can be made many times lighter than the lightest solid surface radiators (heat pipes). The liquid droplet radiator (LDR) is less vulnerable to damage by micrometeoroids than solid surface radiators, and may be transported into space far more efficiently. Analyses are presented of LDR applications in thermal and photovoltaic energy conversion which indicate that fluid handling components (droplet generator, droplet collector, heat exchanger, and pump) may comprise most of the radiator system mass. Even the unoptimized models employed yield LDR system masses less than heat pipe radiator system masses, and significant improvement is expected using design approaches that incorporate fluid handling components more efficiently. Technical problems (e.g., spacecraft contamination and electrostatic deflection of droplets) unique to this method of heat rejectioon are discussed and solutions are suggested.

  6. Thermal performance analysis of a phase change thermal storage unit for space heating

    Energy Technology Data Exchange (ETDEWEB)

    Halawa, E.; Saman, W. [Institute for Sustainable Systems and Technologies School of Advanced Manufacturing and Mechanical Engineering, University of South Australia, Mawson Lakes SA 5095 (Australia)

    2011-01-15

    This paper presents the results of a comprehensive numerical study on the thermal performance of an air based phase change thermal storage unit (TSU) for space heating. The unit is designed for integration into space heating and cooling systems. The unit consists of a number of one dimensional phase change material (PCM) slabs contained in a rectangular duct where air passes between the slabs. The numerical analysis was based on an experimentally validated model. A parametric study has been carried out including the study on the effects of charge and discharge temperature differences, air mass flow rate, slab thicknesses, air gaps and slab dimensions on the air outlet temperatures and heat transfer rates of the thermal storage unit. The paper introduces and discusses quantities called charge and discharge temperature differences which play an important role in the melting and freezing processes. (author)

  7. A study of upwind schemes on the laminar hypersonic heating predictions for the reusable space vehicle

    Science.gov (United States)

    Qu, Feng; Sun, Di; Zuo, Guang

    2018-06-01

    With the rapid development of the Computational Fluid Dynamics (CFD), Accurate computing hypersonic heating is in a high demand for the design of the new generation reusable space vehicle to conduct deep space exploration. In the past years, most researchers try to solve this problem by concentrating on the choice of the upwind schemes or the definition of the cell Reynolds number. However, the cell Reynolds number dependencies and limiter dependencies of the upwind schemes, which are of great importance to their performances in hypersonic heating computations, are concerned by few people. In this paper, we conduct a systematic study on these properties respectively. Results in our test cases show that SLAU (Simple Low-dissipation AUSM-family) is with a much higher level of accuracy and robustness in hypersonic heating predictions. Also, it performs much better in terms of the limiter dependency and the cell Reynolds number dependency.

  8. Improvement of Thrust Bearing Calculation Considering the Convectional Heating within the Space between the Pads

    OpenAIRE

    Monika Chmielowiec-Jablczyk; Andreas Schubert; Christian Kraft; Hubert Schwarze; Michal Wodtke; Michal Wasilczuk

    2018-01-01

    A modern thrust bearing tool is used to estimate the behavior of tilting pad thrust bearings not only in the oil film between pad and rotating collar, but also in the space between the pads. The oil flow in the space significantly influences the oil film inlet temperature and the heating of pad and collar. For that reason, it is necessary to define an oil mixing model for the space between the pads. In the bearing tool, the solutions of the Reynolds equation including a cavitation model, the ...

  9. Heading towards the nZEB through CHP+HP systems. A comparison between retrofit solutions able to increase the energy performance for the heating and domestic hot water production in residential buildings

    International Nuclear Information System (INIS)

    Salata, Ferdinando; Golasi, Iacopo; Domestico, Umberto; Banditelli, Matteo; Lo Basso, Gianluigi; Nastasi, Benedetto; Lieto Vollaro, Andrea de

    2017-01-01

    Highlights: • Energy optimization measures to increase the energy class of buildings. • Analysis of the demands related to the space-heating season and the production of annual DHW. • Case study related to a residential building of medium size located in Rome (Italy). • Improvements on building envelope and on systems (traditional technologies or CHP+HP). • Energy and economic analysis to achieve the performance of a nZEB. - Abstract: Optimizing consumptions in the field of civil construction led to define energy labels for residential buildings. To calculate the building energy demand the EPgl was determined, i.e. the annual consumption per m"2 of primary energy. This paper examines the technical solutions useful to optimize the energy demands for heating during space-heating season and domestic hot water production (thanks to energy analysis softwares as MC11300 and TRNSYS) and, at the same time, to take into account the financial issues those interventions implied. The total inside heated surface of the building case study is 1204.00 m"2, hence the inside heated volume is about 3250.80 m"3. Besides the more traditional interventions concerning the building envelope and its systems, the paper examined the performance of a system obtained through the combination of a cogenerator (CHP) and a heat pump (HP), thus, substituting the conventional boilers of the buildings. CHP+HP solution increases the most the energy label of the building (from a D class with EPgl = 59.62 kW h m"−"2 year"−"1, to an A class, with EPgl = 25.64 kW h m"−"2 year"−"1), determining an annual energy cost saving of 3,114 € year"−"1, allowing to amortize installation costs (54,560 €) in a reasonable payback period, i.e. 15.4 years. This innovative solution in the residential sector can be realized through retrofit interventions on existing buildings, hence it leads the current dwelling towards nZEB with a remarkable benefits for the environment.

  10. Alternative solutions for inhibiting Legionella in domestic hot water systems based on low-temperature district heating

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2015-01-01

    Abstract District heating is a cost-effective way of providing heat to high heat density areas. Low-temperature district heating (LTDH) is a promising way to make district heating more energy-efficient and adaptable to well-insulated buildings with low heating demand in the future. However, one c...... systems. They have the additional benefit of reducing the heat loss of the hot water system. The alternative design solutions both enrich our options for water sanitation and improve the energy efficiency of our energy systems....... concern is the multiplication of Legionella due to insufficient temperature elevation with low-temperature supply. The aim of this study was to find optimal solutions to this dilemma for specific situations. The solutions were of two types: alternative system designs and various methods of sterilization...... methods, thermal treatment, ionization, chlorine, chlorine dioxide, ultraviolet light, photocatalysis and filtration are discussed as the most frequently used methods in hot water systems. The characteristics, efficacy and operation methods of LTDH using the solutions investigated are documented...

  11. Solar Heating and Cooling of Buildings (Phase O). Volume 1: Executive Summary.

    Science.gov (United States)

    TRW Systems Group, Redondo Beach, CA.

    The purpose of this study was to establish the technical and economic feasibility of using solar energy for the heating and cooling of buildings. Five selected building types in 14 selected cities were used to determine loads for space heating, space cooling and dehumidification, and domestic service hot water heating. Relying on existing and…

  12. Field evaluation and assessment of thermal energy storage for residential space heating

    Science.gov (United States)

    Hersh, H. N.

    1982-02-01

    A data base was developed based on two heating seasons and 45 test and 30 control homes in Maine and Vermont. Based on first analysis of monitored temperatures and electrical energy used for space heating, fuel bills and reports of users and utilities, the technical performance of TES ceramic and hydronic systems is deemed to be technically satisfactory and there is a high degree of customer acceptance and positive attitudes towards TES. Analysis of house data shows a high degree of variability in electric heat energy demand for a given degree-day. An analysis is underway to investigate relative differences in the efficiency of electricity utilization of storage and direct heating devices. The much higher price of storge systems relative to direct systems is an impediment to market penetration. A changing picture of rate structures may encourage direct systems at the expense of storage systems.

  13. Main physical environmental drivers of occupant behaviour with regard to space heating energy demand

    DEFF Research Database (Denmark)

    Fabi, Valentina; Andersen, Rune Korsholm; Corgnati, Stefano Paolo

    2012-01-01

    Several studies have highlighted the significant gap between the predicted energy performance of buildings and their measured actual performance. Uncertainties regarding behaviour of building occupants are one of the key factors limiting the ability of energy simulation tools to accurately predict...... real building energy requirements . The paper focuses on the particular topics of space heating energy demand related to the occupants habits of adjusting heating set-points. The parameters influencing the user interaction with the heating control system are analyzed in literature for residential......) environmental conditions and the occupants’ heating set-point preferences. The paper aims at providing a reliable basis for a more accurate description of control action models in performance simulation applications....

  14. User's manual for the Heat Pipe Space Radiator design and analysis Code (HEPSPARC)

    Science.gov (United States)

    Hainley, Donald C.

    1991-01-01

    A heat pipe space radiatior code (HEPSPARC), was written for the NASA Lewis Research Center and is used for the design and analysis of a radiator that is constructed from a pumped fluid loop that transfers heat to the evaporative section of heat pipes. This manual is designed to familiarize the user with this new code and to serve as a reference for its use. This manual documents the completed work and is intended to be the first step towards verification of the HEPSPARC code. Details are furnished to provide a description of all the requirements and variables used in the design and analysis of a combined pumped loop/heat pipe radiator system. A description of the subroutines used in the program is furnished for those interested in understanding its detailed workings.

  15. Anthropogenic Heat Flux Estimation from Space: Results of the second phase of the URBANFLUXES Project

    Science.gov (United States)

    Chrysoulakis, Nektarios; Marconcini, Mattia; Gastellu-Etchegorry, Jean-Philippe; Grimmond, Sue; Feigenwinter, Christian; Lindberg, Fredrik; Del Frate, Fabio; Klostermann, Judith; Mitraka, Zina; Esch, Thomas; Landier, Lucas; Gabey, Andy; Parlow, Eberhard; Olofson, Frans

    2017-04-01

    The H2020-Space project URBANFLUXES (URBan ANthrpogenic heat FLUX from Earth observation Satellites) investigates the potential of Copernicus Sentinels to retrieve anthropogenic heat flux, as a key component of the Urban Energy Budget (UEB). URBANFLUXES advances the current knowledge of the impacts of UEB fluxes on urban heat island and consequently on energy consumption in cities. In URBANFLUXES, the anthropogenic heat flux is estimated as a residual of UEB. Therefore, the rest UEB components, namely, the net all-wave radiation, the net change in heat storage and the turbulent sensible and latent heat fluxes are independently estimated from Earth Observation (EO), whereas the advection term is included in the error of the anthropogenic heat flux estimation from the UEB closure. The Discrete Anisotropic Radiative Transfer (DART) model is employed to improve the estimation of the net all-wave radiation balance, whereas the Element Surface Temperature Method (ESTM), adjusted to satellite observations is used to improve the estimation the estimation of the net change in heat storage. Furthermore the estimation of the turbulent sensible and latent heat fluxes is based on the Aerodynamic Resistance Method (ARM). Based on these outcomes, QF is estimated by regressing the sum of the turbulent heat fluxes versus the available energy. In-situ flux measurements are used to evaluate URBANFLUXES outcomes, whereas uncertainties are specified and analyzed. URBANFLUXES is expected to prepare the ground for further innovative exploitation of EO in scientific activities (climate variability studies at local and regional scales) and future and emerging applications (sustainable urban planning, mitigation technologies) to benefit climate change mitigation/adaptation. This study presents the results of the second phase of the project and detailed information on URBANFLUXES is available at: http://urbanfluxes.eu

  16. Investigation of heat exchangers for energy conversion systems of megawatt-class space power plants

    Science.gov (United States)

    Ilmov, D. N.; Mamontov, Yu. N.; Skorohodov, A. S.; Smolyarov, V. A.; Filatov, N. I.

    2016-01-01

    The specifics of operation (high temperatures in excess of 1000 K and large pressure drops of several megapascals between "hot" and "cold" coolant paths) of heat exchangers in the closed circuit of a gasturbine power converter operating in accordance with the Brayton cycle with internal heat recovery are analyzed in the context of construction of space propulsion systems. The design of a heat-exchange matrix made from doubly convex stamped plates with a specific surface relief is proposed. This design offers the opportunity to construct heat exchangers with the required parameters (strength, rigidity, weight, and dimensions) for the given operating conditions. The diagram of the working area of a test bench is presented, and the experimental techniques are outlined. The results of experimental studies of heat exchange and flow regimes in the models of heat exchangers with matrices containing 50 and 300 plates for two pairs of coolants (gas-gas and gas-liquid) are detailed. A criterion equation for the Nusselt number in the range of Reynolds numbers from 200 to 20 000 is proposed. The coefficients of hydraulic resistance for each coolant path are determined as functions of the Reynolds number. It is noted that the pressure in the water path in the "gas-liquid" series of experiments remained almost constant. This suggests that no well-developed processes of vaporization occurred within this heat-exchange matrix design even when the temperature drop between gas and water was as large as tens or hundreds of degrees. The obtained results allow one to design flight heat exchangers for various space power plants.

  17. Optimization of China's centralized domestic hot water system by applying Danish elements

    DEFF Research Database (Denmark)

    Zhang, Lipeng; Gudmundsson, Oddgeir; Thorsen, Jan Eric

    2014-01-01

    Regardless of where they are in the world, people depend on a reliable and sufficient supply of domestic hot water (DHW) for daily use. Some countries that have district heating (DH) infrastructure, such as Denmark and China, combine spacing heating (SH) and DHW together, with the aim of having...

  18. Heat pipes in modern heat exchangers

    International Nuclear Information System (INIS)

    Vasiliev, Leonard L.

    2005-01-01

    Heat pipes are very flexible systems with regard to effective thermal control. They can easily be implemented as heat exchangers inside sorption and vapour-compression heat pumps, refrigerators and other types of heat transfer devices. Their heat transfer coefficient in the evaporator and condenser zones is 10 3 -10 5 W/m 2 K, heat pipe thermal resistance is 0.01-0.03 K/W, therefore leading to smaller area and mass of heat exchangers. Miniature and micro heat pipes are welcomed for electronic components cooling and space two-phase thermal control systems. Loop heat pipes, pulsating heat pipes and sorption heat pipes are the novelty for modern heat exchangers. Heat pipe air preheaters are used in thermal power plants to preheat the secondary-primary air required for combustion of fuel in the boiler using the energy available in exhaust gases. Heat pipe solar collectors are promising for domestic use. This paper reviews mainly heat pipe developments in the Former Soviet Union Countries. Some new results obtained in USA and Europe are also included

  19. Cycle performance of alternative refrigerants for domestic air-conditioning system based on a small finned tube heat exchanger

    International Nuclear Information System (INIS)

    Cheng, Song; Wang, Shuangfeng; Liu, Zhongmin

    2014-01-01

    In order to find alternative refrigerants which exhibit both favorable cycle performance and environmental friendliness, R32 and R290 were utilized to contrast to R22 and R410A as substitutes in the present study. The experiments were conducted with a 5 mm finned tube heat exchanger based on the enthalpy method in a small split household air conditioner. The results showed that in nominal cooling conditions, the COP R of R32 and R290 were 26.8% and 20.4% higher than R22, 7.3% and 2.1% higher than R410A. And in nominal heating conditions, the COP HR of R32 and R290 were both 11.0% higher than R22, 5.3% higher than R410A. The systems with R290 and R32 have similar capacities to that with R22 and R410A in heating mode, but a relatively huge difference of capacities in cooling mode. In consideration of charge amount, R290 could be considered as the most superior alternative refrigerant in air conditioners with the small finned tube heat exchanger. - Highlights: •Comparisons are made in the air conditioner system based on 5 mm tube fin heat exchanger. •The R22 system has a similar performance to others in heating mode while a huge difference in cooling mode. •The optimal charge of R290 is reduced with nearly no decline in the capacity and COP. •SLHX is attached to the system of R290 and successfully promote safety and capacity. •Heat loads are taken into account to evaluate the advantages and disadvantages of R290 and R32

  20. Improvement of Thrust Bearing Calculation Considering the Convectional Heating within the Space between the Pads

    Directory of Open Access Journals (Sweden)

    Monika Chmielowiec-Jablczyk

    2018-02-01

    Full Text Available A modern thrust bearing tool is used to estimate the behavior of tilting pad thrust bearings not only in the oil film between pad and rotating collar, but also in the space between the pads. The oil flow in the space significantly influences the oil film inlet temperature and the heating of pad and collar. For that reason, it is necessary to define an oil mixing model for the space between the pads. In the bearing tool, the solutions of the Reynolds equation including a cavitation model, the energy equation and the heat transfer equation are done iteratively with the finite volume method by considering a constant flow rate. Both effects—laminar/turbulent flow and centrifugal force—are considered. The calculation results are compared with measurements done for a flooded thrust bearing with nominal eight tilting pads with an outer diameter of 180 mm. The heat convection coefficients for the pad surfaces mainly influence the pad temperature field and are adjusted to the measurement results. In the following paper, the calculation results for variable space distances, influence of different parameters on the bearing behavior and operating condition at high load are presented.

  1. Thermal energy storage for electricity-driven space heating in a day-ahead electricity market

    DEFF Research Database (Denmark)

    Pensini, Alessandro

    2012-01-01

    Thermal Energy Storage (TES) in a space heating (SH) application was investigated. The study aimed to determine the economic benefits of introducing TES into an electricity-driven SH system under a day-ahead electricity market. The performance of the TES was assessed by comparing the cost...... of electricity in a system with a TES unit to the case where no storage is in use and the entire heat requirement is fulfilled by purchasing electricity according to the actual load. The study had two goals: 1. Determining how the size – in terms of electricity input (Pmax) and energy capacity (Emax...

  2. Development of a method for the characterization of the oxidation stability of domestic heating oil and domestic heating oil with alternative components using chemiluminescence; Entwicklung einer Analysemethode zur Charakterisierung der Oxidationsstabilitaet von Heizoel EL und Heizoel EL A mittels Chemilumineszenz

    Energy Technology Data Exchange (ETDEWEB)

    Koch, Winfried; Lukito, Jayadi; Schloss, Heide vom [Oel-Waerme-Institut gGmbH (OWI), Aachen-Herzogenrath (Germany)

    2013-04-15

    The project's aim was to develop a process that serves to determine the oxidation stability of heating oil - FAME-/ heating oil - vegetable oil-blends clearly. Due to a directed energy input by means of the process of chemiluminescence, statements about the storage stability and the thermal stability of blends can be made. During the process the ageing of blend components and of the heating oil are taken into consideration. As a result, ageing processes and products of pure heating oil as well as biogenic components can be determined. It was shown that the process is applicable to blends up to an admixture of at least 20 % (V/V) of biogenic components, whereby blends with higher admixture shares can be analyzed as well. According to DIN SPEC 51603 - 6 'Heating Oil Alternative' the admixture of FAME is limited to 20 %(V/V) and the admixture of vegetable oil to 5 % (V/V) because of the distillation range. On the basis of these investigations it could be shown how oxidation products influence the signal process of the chemiluminescence radiation and how they can be correlated by a measurable physical value. Moreover, a new evaluation criterion has been developed. By means of this criterion a good reproducibility - regarding the determination of the oxidation stability according to the chemiluminescence methodology for non-aged fuels - can be achieved. The fuel characteristic decrease in the stability of the tested fuels can be represented only partially by the chemiluminescence process, as the measured values are subject to fluctuations. (orig.)

  3. The market penetration of solar and heat pump systems in Austria 1991

    International Nuclear Information System (INIS)

    Faninger, G.

    1992-02-01

    The market penetration of solar and heat pump systems in Austria in 1991 shows a high interest for solar systems as well as for swimming-pool heating as for domestic hot-water preparation and also an increase in the field of heat pumps especially for space heating. (author)

  4. Development and preliminary assessment of the wall condensation heat transfer models for the SPACE code

    International Nuclear Information System (INIS)

    Park, Hyun Sik; Choi, Ki Yong; Moon, Sang Ki; Kim, Jung Woo; Kim, Kyung Doo

    2009-01-01

    The wall condensation heat transfer models are developed for the SPACE code and are assessed for various condensation conditions. Both default and alternative models were selected through an extensive literature survey. For a pure steam condensation, a maximum value among the Nusselt, Chato, and Shah's correlations is used in order to consider the geometric and turbulent effects. In the presence of non-condensable gases, the Colburn-Hougen's diffusion model was used as a default model and a non-iterative condensation model proposed by No and Park was selected as an alternative model. The wall condensation heat transfer models were assessed preliminarily by using arbitrary test conditions. Both wall condensation models could simulate the heat transfer coefficients and heat fluxes in the vertical, horizontal and turbulent conditions quite reasonably for a pure steam condensation. Both the default and alternative wall condensation models were also verified for the condensation heat transfer coefficient and heat flux in the presence of noncondensable gas. However, some improvements and further detailed verification are necessary for the condensation phenomena in the presence of noncondensable gas

  5. Assessment of CFD Hypersonic Turbulent Heating Rates for Space Shuttle Orbiter

    Science.gov (United States)

    Wood, William A.; Oliver, A. Brandon

    2011-01-01

    Turbulent CFD codes are assessed for the prediction of convective heat transfer rates at turbulent, hypersonic conditions. Algebraic turbulence models are used within the DPLR and LAURA CFD codes. The benchmark heat transfer rates are derived from thermocouple measurements of the Space Shuttle orbiter Discovery windward tiles during the STS-119 and STS-128 entries. The thermocouples were located underneath the reaction-cured glass coating on the thermal protection tiles. Boundary layer transition flight experiments conducted during both of those entries promoted turbulent flow at unusually high Mach numbers, with the present analysis considering Mach 10{15. Similar prior comparisons of CFD predictions directly to the flight temperature measurements were unsatisfactory, showing diverging trends between prediction and measurement for Mach numbers greater than 11. In the prior work, surface temperatures and convective heat transfer rates had been assumed to be in radiative equilibrium. The present work employs a one-dimensional time-accurate conduction analysis to relate measured temperatures to surface heat transfer rates, removing heat soak lag from the flight data, in order to better assess the predictive accuracy of the numerical models. The turbulent CFD shows good agreement for turbulent fuselage flow up to Mach 13. But on the wing in the wake of the boundary layer trip, the inclusion of tile conduction effects does not explain the prior observed discrepancy in trends between simulation and experiment; the flight heat transfer measurements are roughly constant over Mach 11-15, versus an increasing trend with Mach number from the CFD.

  6. Estimating end-use emissions factors for policy analysis: the case of space cooling and heating.

    Science.gov (United States)

    Jacobsen, Grant D

    2014-06-17

    This paper provides the first estimates of end-use specific emissions factors, which are estimates of the amount of a pollutant that is emitted when a unit of electricity is generated to meet demand from a specific end-use. In particular, this paper provides estimates of emissions factors for space cooling and heating, which are two of the most significant end-uses. The analysis is based on a novel two-stage regression framework that estimates emissions factors that are specific to cooling or heating by exploiting variation in cooling and heating demand induced by weather variation. Heating is associated with similar or greater CO2 emissions factor than cooling in all regions. The difference is greatest in the Midwest and Northeast, where the estimated CO2 emissions factor for heating is more than 20% larger than the emissions factor for cooling. The minor differences in emissions factors in other regions, combined with the substantial difference in the demand pattern for cooling and heating, suggests that the use of overall regional emissions factors is reasonable for policy evaluations in certain locations. Accurately quantifying the emissions factors associated with different end-uses across regions will aid in designing improved energy and environmental policies.

  7. Effect of the inter-block spacing on the thermal performance of a PCM based heat sink

    Energy Technology Data Exchange (ETDEWEB)

    Faraji, M.; El Qarnia, H. [Cadi Ayyad Univ., Marrakech (Morocco). Faculte des sciences Semlalia, Dept. de physique, Laboratoire de mecanique des fluides et d' energetique; El Khadir, L. [Cadi Ayyad Univ., Marrakech (Morocco). Faculte des sciences Semlalia, Dept. de physique, Laboratoire d' tomatique de l' Environnement et Procedes de Transferts

    2010-07-01

    Advanced electronic devices require efficient thermal control systems. Heat transfer analysis of such systems is challenging because of constraints regarding space limitations, power consumption and noise level. This study considered the problem of melting and natural convection in a rectangular enclosure heated with 3 heat sources with a constant and uniform volumetric heat generation. The heat sources were protruding and mounted on a vertical conducting plate. Conjugate conduction in a plate and heat sources coupled with natural convection and melting process were examined in an effort to determine the effects of the inter-blocks spacing ratio on the thermal performance of the cooling PCM-heat sink. The percentage contribution of substrate heat conduction on the total removed heat from heat sources was also investigated. Correlations were derived for the non- dimensional secured working time and the corresponding melt fraction. In order to investigate the thermal behaviour of the proposed heat sink, a mathematical model was developed based on the mass, momentum and energy conservation equations. The results revealed that for lower inter-blocks spacing, the dimensionless secured working time needed by the chips to reach the critical temperature was maximized. The highest inter-blocks spacing ratio provoked a sudden rise in chip temperatures and thus reduced the dimensionless secured working time. It was concluded that this approach can be used in the design of PCM-based cooling systems. 9 refs., 2 tabs., 4 figs.

  8. Measurement and analysis of SPS kicker magnet heating and outgassing with Different Bunch Spacing

    CERN Document Server

    Barnes, M J; Cornelis, K; Ducimetière, L; Mahner, E; Papotti, G; Rumolo, G; Senaj, V; Shaposhnikova, E

    2010-01-01

    Fast kicker magnets are used to inject beam into and eject beam out of the CERN SPS accelerator ring. These kickers are generally ferrite loaded transmission line type magnets with a rectangular shaped aperture through which the beam passes. Unless special precautions are taken the impedance of the ferrite yoke can provoke significant beam induced heating, over several hours, even above the Curie temperature of the ferrite. At present the nominal bunch spacing in the SPS is 25 ns, however for an early stage of LHC operation it is preferable to have 50 ns bunch spacing. Machine Development (MD) studies have been carried out with an inter-bunch spacing of 25 ns, 50 ns or 75 ns. For some of the SPS kicker magnets the 75 ns bunch spacing resulted in considerable beam induced heating. In addition the MDs showed that 50 ns bunch spacing could result in a very rapid pressure rise in the kicker magnet and thus cause an interlock. This paper discusses the MD observations of the SPS kickers and analyses the available d...

  9. Heating of a fully saturated darcian half-space: Pressure generation, fluid expulsion, and phase change

    Science.gov (United States)

    Delaney, P.

    1984-01-01

    Analytical solutions are developed for the pressurization, expansion, and flow of one- and two-phase liquids during heating of fully saturated and hydraulically open Darcian half-spaces subjected to a step rise in temperature at its surface. For silicate materials, advective transfer is commonly unimportant in the liquid region; this is not always the case in the vapor region. Volume change is commonly more important than heat of vaporization in determining the position of the liquid-vapor interface, assuring that the temperatures cannot be determined independently of pressures. Pressure increases reach a maximum near the leading edge of the thermal front and penetrate well into the isothermal region of the body. Mass flux is insensitive to the hydraulic properties of the half-space. ?? 1984.

  10. How low can the low heating load density district heating be? Environmental aspects on low heating load density district heating of the present generation compared to a domestic oil burner; Hur vaermegles kan den vaermeglesa fjaerrvaermen vara? Miljoeaspekter paa vaermegles fjaerrvaerme med dagens teknik jaemfoerd med villaoljepanna

    Energy Technology Data Exchange (ETDEWEB)

    Froeling, Morgan [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Chemical Environmental Science

    2005-07-01

    In Sweden we can see an increase of district heating networks in residential areas with low heat density. For the customer the economy is normally the most important argument when deciding to choose district heating. For many customers, however, arguments regarding environmental friendliness are important complimentary arguments. When district heating systems are built with decreased heat density, the environmental impacts from use of district heating will increase, depending on such as increased need of pipes and increased heat losses from the distribution system. The purpose of this study is to investigate if there is a limit, a lowest heat density when it is not any longer beneficial to build district heating when district heating replaces local oil furnace heating. Life cycle inventory data for district heating distribution systems in areas with low heat density has been compared with the use of oil furnaces. The environmental impacts are categorized into Global Warming Potential, Acidification Potential, Eutrofication Potential and Use of Finite Resources. To enhance the assessment three single point indicators have also been used: EcoIndicator99, EPS and ExternE. The economics of using district heating in areas with low heat density has not been regarded in this study. A model comparing the space heating of a single family home with an oil furnace or with district heating has been created. The home has an annual heat need of 20 MWh. The district heating distribution network is characterized by its linear heat density. The linear heat density is a rough description of a district heating network, and thus also the results from the model will be general. Still it can give us a general idea of the environmental limit for district heating in areas with low heat density. An assessment of all results indicate that with the type of technology used at present it is not environmentally beneficial to use district heating with lower linear heat density than 0,2 MWh/m. At

  11. Frosting characteristics and heating performance of a direct-expansion solar-assisted heat pump for space heating under frosting conditions

    International Nuclear Information System (INIS)

    Huang, Wenzhu; Ji, Jie; Xu, Ning; Li, Guiqiang

    2016-01-01

    Highlights: • Frosting and heating performance of DX-SAHP under frosting conditions is investigated. • The conditions when DX-SAHP frosts are studied. • The frosting process is observed during 360 min of operating. • The effect of ambient temperature, relative humidity and solar irradiation is analyzed. - Abstract: Direct expansion solar-assisted heat pump system (DX-SAHP) is promising in energy saving applications, but the performance of DX-SAHP under frosting conditions is rarely reported in the published literatures. In this paper, a DX-SAHP system with bare solar collectors for space heating is designed and experimentally investigated in the enthalpy difference lab with a solar simulator. The system is tested under a range of frosting conditions, with the ambient temperatures from 7 °C to −3 °C, the relative humidities of 50%, 70% and 90% and the solar irradiances of 0 W/m"2, 100 W/m"2, 200 W/m"2 and 300 W/m"2. The conditions when the DX-SAHP system frosts are studied. Results show that solar irradiance as low as 100 W/m"2 can totally prevent frosting when the ambient temperature is above −3 °C and the relative humidity is 70%. Besides, the frosting process is observed to be slower than that of fin-and-tube heat exchangers. The evaporator is not seriously frosted and the system performance is not significantly influenced after 360 min of continuous operating. Moreover the effects of ambient parameters, including the ambient temperature and the relative humidity, especially solar irradiation, on the system performance are studied and analyzed. Solar irradiation can effectively prevent or retard frosting, and also improve the heating performance of the DX-SAHP system. The DX-SAHP system is proved to be applicable under frosting conditions.

  12. General-purpose heat source project and space nuclear safety and fuels program. Progress report

    International Nuclear Information System (INIS)

    Maraman, W.J.

    1979-12-01

    This formal monthly report covers the studies related to the use of 238 PuO 2 in radioisotopic power systems carried out for the Advanced Nuclear Systems and Projects Division of the Los Alamos Scientific Laboratory. The two programs involved are general-purpose heat source development and space nuclear safety and fuels. Most of the studies discussed hear are of a continuing nature. Results and conclusions described may change as the work continues

  13. Heat Transfer and Fluid Dynamics Measurements in the Expansion Space of a Stirling Cycle Engine

    Science.gov (United States)

    Jiang, Nan; Simon, Terrence W.

    2006-01-01

    The heater (or acceptor) of a Stirling engine, where most of the thermal energy is accepted into the engine by heat transfer, is the hottest part of the engine. Almost as hot is the adjacent expansion space of the engine. In the expansion space, the flow is oscillatory, impinging on a two-dimensional concavely-curved surface. Knowing the heat transfer on the inside surface of the engine head is critical to the engine design for efficiency and reliability. However, the flow in this region is not well understood and support is required to develop the CFD codes needed to design modern Stirling engines of high efficiency and power output. The present project is to experimentally investigate the flow and heat transfer in the heater head region. Flow fields and heat transfer coefficients are measured to characterize the oscillatory flow as well as to supply experimental validation for the CFD Stirling engine design codes. Presented also is a discussion of how these results might be used for heater head and acceptor region design calculations.

  14. Convection heat transfer of closely-spaced spheres with surface blowing

    Energy Technology Data Exchange (ETDEWEB)

    Kleinstreuer, C. (North Carolina State Univ., Raleigh, NC (United States). Dept. of Mechanical and Aerospace Engineering); Chiang, H. (Thermofluid Technology Div., Industrial Technology Research Inst., Chutung (Taiwan, Province of China))

    1993-05-01

    A validated computer simulation model has been developed for the analysis of colinear spheres in a heated gas stream. Using the Galerkin finite element method, the steady-state Navier-Stokes and heat transfer equations have been solved describing laminar axisymmetric thermal flow past closely-spaced monodisperse spheres with fluid injection. Of interest are the coupled nonlinear interaction effects on the temperature fields and ultimately on the Nusselt number of each sphere for different free stream Reynolds numbers (20 [<=] Re [<=] 200) and intersphere distances (1.5 [<=] d[sub ij] [<=] 6.0) in the presence of surface blowing (0 [<=] v[sub b] [<=] 0.1). Fluid injection (i.e. blowing) and associated wake effects generate lower average heat transfer coefficients for each interacting sphere when the Reynolds number increases (Re > 100). Heat transfer is also reduced at small spacings especially for the second and third sphere. A Nusselt number correlation for each interacting (porous) sphere has been developed based on computer experiments. (orig.)

  15. Utah State Prison Space Heating with Geothermal Heat Second Semi-Annual Report for the Period June 1980 - December 1980

    Energy Technology Data Exchange (ETDEWEB)

    None

    1981-04-01

    Reported herein is a summary of work conducted during the six monty period June, 1980 through December, 1980 of the project under contract to develop the Crystal Hot Springs geothermal resource to provide space and hot water heating for the minimum security building at the Utah State Prison. Efforts during this reporting period have been directed towards the resource assessment phase of the program. Specifically, progress includes: (1) completion of the gravity modeling efforts to define the subsurface structural configuration in the vicinity of the Crystal Hot Springs area, (2) selection of the most promising production targets for a test drilling program, (3) completion of the test drilling program, and (4) testing and monitoring of test well USP/TH-1.

  16. Conceptual Design of a Condensing Heat Exchanger for Space Systems Using Porous Media

    Science.gov (United States)

    Hasan, Mohammad M.; Khan, Lutful I.; Nayagam, Vedha; Balasubramaniam, Ramaswamy

    2006-01-01

    Condensing heat exchangers are used in many space applications in the thermal and humidity control systems. In the International Space Station (ISS), humidity control is achieved by using a water cooled fin surface over which the moist air condenses, followed by "slurper bars" that take in both the condensate and air into a rotary separator and separates the water from air. The use of a cooled porous substrate as the condensing surface provides and attractive alternative that combines both heat removal as well as liquid/gas separation into a single unit. By selecting the pore sizes of the porous substrate a gravity independent operation may also be possible with this concept. Condensation of vapor into and on the porous surface from the flowing air and the removal of condensate from the porous substrate are the critical processes involved in the proposed concept. This paper describes some preliminary results of the proposed condensate withdrawal process and discusses the on-going design and development work of a porous media based condensing heat exchanger at the NASA Glenn Research Center in collaboration with NASA Johnson Space Center.

  17. Experimental analysis of a direct expansion solar assisted heat pump with integral storage tank for domestic water heating under zero solar radiation conditions

    International Nuclear Information System (INIS)

    Fernández-Seara, José; Piñeiro, Carolina; Alberto Dopazo, J.; Fernandes, F.; Sousa, Paulo X.B.

    2012-01-01

    Highlights: ► We analyze a direct expansion solar assisted heat pump under zero solar radiation. ► We determine the COP and equivalent seasonal performance factors (SPFe). ► We determine the main components’ performance under transient operating conditions. ► The Huang and Lee performance evaluation method provides a characteristic COP of 3.23. - Abstract: This paper deals with the experimental evaluation of the performance of a direct expansion solar assisted heat pump water heating (DX-SAHPWH) system working under zero solar radiation conditions at static heating operation mode of the storage tank. The DX-SAHPWH system includes two bare solar collectors as evaporator, a R134a rotary-type hermetic compressor, a thermostatic expansion valve and a helical coil condenser immersed in a 300 L water storage tank. The zero solar radiation and stable ambient air temperature working conditions were established by placing the solar collectors into a climate chamber. The analysis is based on experimental data taken from the DX-SAHPWH provided by the manufacturer and equipped with an appropriate data acquisition system. In the paper, the experimental facility, the data acquisition system and the experimental methodology are described. Performance parameters to evaluate the energy efficiency, such as COP and equivalent seasonal performance factors (SPFe) for the heating period, and the water thermal stratification in the storage tank are defined and obtained from the experimental data. Results from the experimental analysis under transient operating working conditions of the DX-SAHPWH system and its main components are shown and discussed. Lastly, the Huang and Lee DX-SAHPWH performance evaluation method was applied resulting in a characteristic COP of 3.23 for the DX-SAHPWH system evaluated under zero solar radiation condition.

  18. Utah State Prison Space Heating with Geothermal Heat Third Semi-Annual Report for the Period January 1981 - July 1981

    Energy Technology Data Exchange (ETDEWEB)

    None

    1981-11-01

    Facing certain cost overruns and lacking information about the long term productivity of the Crystal Hot Springs geothermal resource, costs of construction for the geothermal retrofit, and the method of disposal of geothermal waste water, the Energy Office embarked on a strategy that would enable the project participants to develop accurate cost information on the State Prison Space Heating Program through the completion of Task 5-Construction. The strategy called for: (1) Completion of the resource assessment to determine whether test well USP/TH-1 could be used as a production well. If well USP/TH-1 was found to have sufficient production capacity, money would not have to be expended on drilling another production well. (2) Evaluation of disposal alternatives and estimation of the cost of each alternative. There was no contingency in the original budget to provide for a reinjection disposal system. Cooperative agreement DE EC07-ET27027 indicated that if a disposal system requiring reinjection was selected for funding that task would be negotiated with DOE and the budget amended accordingly. (3) Completion of the preliminary engineering and design work. Included in this task was a thorough net present value cash flow analysis and an assessment of the technical feasibility of a system retrofit given the production characteristics of well USP/TH-1 . In addition, completion of the preliminary design would provide cost estimates for the construction and commissioning of the minimum security geothermal space heating system. With this information accurate costs for each task would be available, allowing the Energy Office to develop strategies to optimize the use of money in the existing budget to ensure completion of the program. Reported herein is a summary of the work towards the completion of these three objectives conducted during the period of January 1981 through June 1981.

  19. Greenhouse gas and energy analysis of substitute natural gas from biomass for space heat

    Energy Technology Data Exchange (ETDEWEB)

    Pucker, J.; Jungmeier, G. [JOANNEUM RESEARCH Forschungsgesellschaft mbH, RESOURCES - Institute for Water, Energy and Sustainability, Steyrergasse 17, 8010 Graz (Austria); Zwart, R. [Energy Research Centre of The Netherlands (ECN), Westerduinweg 3, 1755 LE Petten (Netherlands)

    2012-03-15

    In this paper, the greenhouse gas and energy balances of the production and use for space heating of substitute natural gas from biomass (bio-SNG) for space heat are analysed. These balances are compared to the use of natural gas and solid biomass as wood chips to provide the same service. The reduction of the greenhouse gas emissions (CO{sub 2}-eq.) - carbon dioxide, methane and nitrous oxide - and of the fossil primary energy use is investigated in a life cycle assessment (LCA). This assessment was performed for nine systems for bio-SNG; three types of gasification technologies (O{sub 2}-blown entrained flow, O{sub 2}-blown circulating fluidised bed and air-steam indirect gasification) with three different types of feedstock (forest residues, miscanthus and short rotation forestry). The greenhouse gas analysis shows that forest residues using the air-steam indirect gasification technology result in the lowest greenhouse gas emissions (in CO{sub 2}-eq. 32 kg MWh{sup -1} of heat output). This combination results in 80% reduction of greenhouse gas emissions when compared to natural gas and a 29% reduction of greenhouse gases if the forest residues were converted to wood chips and combusted. The gasification technologies O{sub 2}-blown entrained flow and O{sub 2}-blown circulating fluidised bed gasification have higher greenhouse gas emissions that range between in CO{sub 2}-eq. 41 to 75 kg MWh{sup -1} of heat output depending on the feedstock. When comparing feedstocks in the bio-SNG systems, miscanthus had the highest greenhouse gas emissions bio-SNG systems producing in CO2-eq. 57-75 kg MWh{sup -1} of heat output. Energy analysis shows that the total primary energy use is higher for bio-SNG systems (1.59-2.13 MWh MWh{sup -1} of heat output) than for the reference systems (in 1.37-1.51 MWh MWh{sup -1} of heat output). However, with bio-SNG the fossil primary energy consumption is reduced compared to natural gas. For example, fossil primary energy use is reduced by

  20. Performance of a Solar Heating System with Photovoltaic Thermal Hybrid Collectors and Heat Pump

    DEFF Research Database (Denmark)

    Dannemand, Mark; Furbo, Simon; Perers, Bengt

    2017-01-01

    . When the solar collectors are unable to supply the heat demand an auxiliary heat source is used. Heat pumps can generate this heat. Liquid/water heat pumps have better performance than air/water heat pumps in cold climates but requires installation of a tubing system for the cold side of the heat pump....... The tubes are typically placed in the ground, requires a significant land area and increase the installation cost. A new system design of a solar heating system with two storage tanks and a liquid/water heat pump is presented. The system consists of PVT collectors that generate both heat and electricity......The energy consumption in buildings accounts for a large part of the World’s CO2 emissions. Much energy is used for appliances, domestic hot water preparation and space heating. In solar heating systems, heat is captured by solar collectors when the sun is shining and used for heating purposes...

  1. Space shuttle/food system study. Volume 2, Appendix A: Active heating system-screening analysis. Appendix B: Reconstituted food heating techniques analysis

    Science.gov (United States)

    1974-01-01

    Technical data are presented which were used to evaluate active heating methods to be incorporated into the space shuttle food system design, and also to evaluate the relative merits and penalties associated with various approaches to the heating of rehydrated food during space flight. Equipment heating candidates were subject to a preliminary screening performed by a selection rationale process which considered the following parameters; (1) gravitational effect; (2) safety; (3) operability; (4) system compatibility; (5) serviceability; (6) crew acceptability; (7) crew time; (8) development risk; and (9) operating cost. A hot air oven, electrically heated food tray, and microwave oven were selected for further consideration and analysis. Passive, semi-active, and active food preparation approaches were also studied in an effort to determine the optimum method for heating rehydrated food. Potential complexity, cost, vehicle impact penalties, and palatability were considered in the analysis. A summary of the study results is provided along with cost estimates for each of the potential sytems

  2. TRIGENERATION - A highly energy efficient source for heating, domestic hot water preparation, electricity and air cooling systems for tertiary sector

    International Nuclear Information System (INIS)

    Barbuta, Mariana; Ghitulescu, Mircea; Nicolau, Irina; Athanasovici, Cristian; Constantin, Cristinel; Ivan, Robert

    2004-01-01

    The general concerns relating to sustainable energy development have led to the implementation of certain solutions at the international level that have increased both energy generation and energy consuming processes efficiency. In our country the first steps in this direction have been carried out by the private companies that, after having analyzed the income increase and costs diminishing, have come to the conclusion that a reliable way to save money would be the rational use of the energy resources for utilities. A favorable consequence was the synergetic effect of the measures meant to increase energy efficiency for the energy generation and consumption processes that are also accompanied by benefit effects on the environmental impact by reduction CO 2 emissions. One of the solutions making the utmost of primary energy is the combined heat and power production (co-generation) that has significantly developed in our country within the energy sector as a whole. Co-generation may be considered environmentally friendly because it saves fuel on the one hand and, technologically, generates less emissions as compared to the separate generation of heat and power, on the other hand. The most favorable applications of co-generation at a medium and small scale are in the tertiary sector (hotels, hospitals, and office buildings) where heat consumption is usually high enough and is accompanied by relatively constant electricity consumption. By corroborating the above mentioned facts relating to local cogeneration installation utilization with those relating to the increased need for cooling in the tertiary buildings, a concept named 'TRI-GENERATION' in specialized literature has occurred, representing, in fact, utilization of cogeneration installations for supplying energy to the electricity, heat and cold consumer. Thus, the cogeneration installation utilization time will be practically prolonged over the entire duration of a year a fact that has extremely favorable

  3. Domestic Violence

    Science.gov (United States)

    Domestic violence is a type of abuse. It usually involves a spouse or partner, but it can also ... a child, elderly relative, or other family member. Domestic violence may include Physical violence that can lead to ...

  4. Domestic violence

    OpenAIRE

    Tačík, Michal

    2015-01-01

    Domestic violence The present thesis deals with the phenomenon of domestic violence, from the substantive, procedural and criminological aspects. The first part defines the specifics of domestic violence, its signs and forms. It shows a typology of victims and perpetrators. It analyzes in detail the basic facts of the crimes that are the most commonly perpetrated forms of domestic violence. It also describes the sanctions and some of the treatment programs that are available for perpetrators ...

  5. The Spanish tourist sector facing extreme climate events: a case study of domestic tourism in the heat wave of 2003

    Science.gov (United States)

    Gómez-Martín, M. Belén; Armesto-López, Xosé A.; Martínez-Ibarra, Emilio

    2014-07-01

    This research explores, by means of a questionnaire-based survey, public knowledge and perception as well as the behaviour of young Spanish tourists before, during and after the summer holiday period affected by an episode of extreme heat in 2003. The survey was administered between November and December 2004. The extraordinary heat wave of the summer of 2003 can be seen as an example of a normal episode in terms of the predicted intensity and duration of European summers towards the end of the twenty-first century. It can therefore be used as the laboratory setting for this study. In this context, the use of the climate analogue approach allows us to obtain novel perspectives regarding the future impact that this type of event could have on tourist demand, based on a real experience. Likewise, such an approach allows the strategies of adaptation implemented by the different elements in the tourist system in order to cope with the atmospheric episode to be evaluated. Such strategies could prove useful in reducing vulnerability when faced with similar episodes in the future. The main results indicate that Spanish tourists (young segment market) are flexible in adapting to episodes of extremely high temperatures. Their personal perception of the phenomenon, their behaviour and the adaptation measures implemented to a greater or lesser extent before that time, reduce the vulnerability of the sector when faced with this type of event, at least from the point of view of this young segment of the internal national market. In Spain, the episode of extreme heat of 2003 has led to the implementation or improvement of some adaptive measures after the event, especially in the fields of management, policy and education.

  6. Greenhouse gas and energy analysis of substitute natural gas from biomass for space heat

    International Nuclear Information System (INIS)

    Pucker, Johanna; Zwart, Robin; Jungmeier, Gerfried

    2012-01-01

    In this paper, the greenhouse gas and energy balances of the production and use for space heating of substitute natural gas from biomass (bio-SNG) for space heat are analysed. These balances are compared to the use of natural gas and solid biomass as wood chips to provide the same service. The reduction of the greenhouse gas emissions (CO 2 -eq.) – carbon dioxide, methane and nitrous oxide – and of the fossil primary energy use is investigated in a life cycle assessment (LCA). This assessment was performed for nine systems for bio-SNG; three types of gasification technologies (O 2 -blown entrained flow, O 2 -blown circulating fluidised bed and air–steam indirect gasification) with three different types of feedstock (forest residues, miscanthus and short rotation forestry). The greenhouse gas analysis shows that forest residues using the air–steam indirect gasification technology result in the lowest greenhouse gas emissions (in CO 2 -eq. 32 kg MWh −1 of heat output). This combination results in 80% reduction of greenhouse gas emissions when compared to natural gas and a 29% reduction of greenhouse gases if the forest residues were converted to wood chips and combusted. The gasification technologies O 2 -blown entrained flow and O 2 -blown circulating fluidised bed gasification have higher greenhouse gas emissions that range between in CO 2 -eq. 41 to 75 kg MWh −1 of heat output depending on the feedstock. When comparing feedstocks in the bio-SNG systems, miscanthus had the highest greenhouse gas emissions bio-SNG systems producing in CO 2 -eq. 57–75 kg MWh −1 of heat output. Energy analysis shows that the total primary energy use is higher for bio-SNG systems (1.59–2.13 MWh MWh −1 of heat output) than for the reference systems (in 1.37–1.51 MWh MWh −1 of heat output). However, with bio-SNG the fossil primary energy consumption is reduced compared to natural gas. For example, fossil primary energy use is reduced by 92% when air

  7. Feasibility of geothermal space/water heating for Mammoth Lakes Village, California. Final report, September 1976--September 1977

    Energy Technology Data Exchange (ETDEWEB)

    Sims, A.V.; Racine, W.C.

    1977-12-01

    Results of a study to determine the technical, economic, and environmental feasibility of geothermal district heating for Mammoth Lakes Village, California are reported. The geothermal district heating system selected is technically feasible and will use existing technology in its design and operation. District heating can provide space and water heating energy for typical customers at lower cost than alternative sources of energy. If the district heating system is investor owned, lower costs are realized after five to six years of operation, and if owned by a nonprofit organization, after zero to three years. District heating offers lower costs than alternatives much sooner in time if co-generation and/or DOE participation in system construction are included in the analysis. During a preliminary environmental assessment, no potential adverse environmental impacts could be identified of sufficient consequence to preclude the construction and operation of the proposed district heating system. A follow-on program aimed at implementing district heating in Mammoth is outlined.

  8. Marangoni convection radiative flow of dusty nanoliquid with exponential space dependent heat source

    Directory of Open Access Journals (Sweden)

    Basavarajappa Mahanthesh

    2017-12-01

    Full Text Available The flow of liquids submerged with nanoparticles is of significance to industrial applications, specifically in nuclear reactors and the cooling of nuclear systems to improve energy efficiency. The application of nanofluids in water-cooled nuclear systems can result in a significant improvement of their economic performance and/or safety margins. Therefore, in this paper, Marangoni thermal convective boundary layer dusty nanoliquid flow across a flat surface in the presence of solar radiation is studied. A two phase dusty liquid model is considered. Unlike classical temperature-dependent heat source effects, an exponential space-dependent heat source aspect is considered. Stretching variables are utilized to transform the prevailing partial differential system into a nonlinear ordinary differential system, which is then solved numerically via the Runge-Kutta-Fehlberg approach coupled with a shooting technique. The roles of physical parameters are focused in momentum and heat transport distributions. Graphical illustrations are also used to consider local and average Nusselt numbers. We examined the results under both linear and quadratic variation of the surface temperature. Our simulations established that the impact of Marangoni flow is useful for an enhancement of the heat transfer rate.

  9. Space chamber experiments of ohmic heating by high power microwave from the solar power satellite

    Energy Technology Data Exchange (ETDEWEB)

    Kaya, N.; Matsumoto, H.

    1981-12-01

    It is quantitatively predicted that a high power microwave from the Solar Power Satellite (SPS) nonlinearly interacts with the ionospheric plasma. The possible nonlinear interactions are ohmic heating, self-focusing and parametric instabilities. A rocket experiment called MINIX (Microwave-Ionosphere Nonlinear Interaction Experiment) has been attempted to examine these effects, but is note reported here. In parallel to the rocket experiment, a laboratory experiment in a space plasma simulation chamber has been carried out in order to examine ohmic heating in detail and to develop a system of the rocket experiment. Interesting results were observed and these results were utilized to revise the system of the rocket experiments. A significant microwave heating of plasma up to 150% temperature increase was observed with little electron density decrease. It was shown that the temperature increase is not due to the RF breakdown but to the ohmic heating in the simulated ionospheric plasma. These microwave effects have to be taken into account in the SPS Project in the future.

  10. Numerical simulations and analyses of temperature control loop heat pipe for space CCD camera

    Science.gov (United States)

    Meng, Qingliang; Yang, Tao; Li, Chunlin

    2016-10-01

    As one of the key units of space CCD camera, the temperature range and stability of CCD components affect the image's indexes. Reasonable thermal design and robust thermal control devices are needed. One kind of temperature control loop heat pipe (TCLHP) is designed, which highly meets the thermal control requirements of CCD components. In order to study the dynamic behaviors of heat and mass transfer of TCLHP, particularly in the orbital flight case, a transient numerical model is developed by using the well-established empirical correlations for flow models within three dimensional thermal modeling. The temperature control principle and details of mathematical model are presented. The model is used to study operating state, flow and heat characteristics based upon the analyses of variations of temperature, pressure and quality under different operating modes and external heat flux variations. The results indicate that TCLHP can satisfy the thermal control requirements of CCD components well, and always ensure good temperature stability and uniformity. By comparison between flight data and simulated results, it is found that the model is to be accurate to within 1°C. The model can be better used for predicting and understanding the transient performance of TCLHP.

  11. Development and test of a space-reactor-core heat pipe

    International Nuclear Information System (INIS)

    Merrigan, M.A.; Runyan, J.E.; Martinez, H.E.; Keddy, E.S.

    1983-01-01

    A heat pipe designed to meet the heat transfer requirements of a 100-kW/sub e/ space nuclear power system has been developed and tested. General design requirements for the device included an operating temperature of 1500 0 K with an evaporator radial flux density of 100 w/cm 2 . The total heat-pipe length of 2 m comprised an evaporator length of 0.3 m, a 1.2-m adiabatic section, and a condenser length of 0.5 m. A four-artery design employing screen arteries and distribution wicks was used with lithium serving as the working fluid. Molybdenum alloys were used for the screen materials and tube shell. Hafnium and zirconium gettering materials were used in connection with a pre-purified distilled lithium charge to ensure internal chemical compatibility. After initial performance verification, the 14.1-mm i.d. heat pipe was operated at 15 kW throughput at 1500 0 K for 100 hours. No performance degradation was observed during the test

  12. Regulation and Measurement of the Heat Generated by Automatic Tooth Preparation in a Confined Space.

    Science.gov (United States)

    Yuan, Fusong; Zheng, Jianqiao; Sun, Yuchun; Wang, Yong; Lyu, Peijun

    2017-06-01

    The aim of this study was to assess and regulate heat generation in the dental pulp cavity and circumambient temperature around a tooth during laser ablation with a femtosecond laser in a confined space. The automatic tooth preparing technique is one of the traditional oral clinical technology innovations. In this technique, a robot controlled an ultrashort pulse laser to automatically complete the three-dimensional teeth preparing in a confined space. The temperature control is the main measure for protecting the tooth nerve. Ten tooth specimens were irradiated with a femtosecond laser controlled by a robot in a confined space to generate 10 teeth preparation. During the process, four thermocouple sensors were used to record the pulp cavity and circumambient environment temperatures with or without air cooling. A statistical analysis of the temperatures was performed between the conditions with and without air cooling (p heat generated in the pulp cavity was lower than the threshold for dental pulp damage. These results indicate that femtosecond laser ablation with air cooling might be an appropriate method for automatic tooth preparing.

  13. Heating of large format filters in sub-mm and fir space optics

    Science.gov (United States)

    Baccichet, N.; Savini, G.

    2017-11-01

    Most FIR and sub-mm space borne observatories use polymer-based quasi-optical elements like filters and lenses, due to their high transparency and low absorption in such wavelength ranges. Nevertheless, data from those missions have proven that thermal imbalances in the instrument (not caused by filters) can complicate the data analysis. Consequently, for future, higher precision instrumentation, further investigation is required on any thermal imbalances embedded in such polymer-based filters. Particularly, in this paper the heating of polymers when operating at cryogenic temperature in space will be studied. Such phenomenon is an important aspect of their functioning since the transient emission of unwanted thermal radiation may affect the scientific measurements. To assess this effect, a computer model was developed for polypropylene based filters and PTFE-based coatings. Specifically, a theoretical model of their thermal properties was created and used into a multi-physics simulation that accounts for conductive and radiative heating effects of large optical elements, the geometry of which was suggested by the large format array instruments designed for future space missions. It was found that in the simulated conditions, the filters temperature was characterized by a time-dependent behaviour, modulated by a small scale fluctuation. Moreover, it was noticed that thermalization was reached only when a low power input was present.

  14. Heat exchanger optimization of a closed Brayton cycle for nuclear space propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Guilherme B.; Guimaraes, Lamartine N.F.; Braz Filho, Francisco A., E-mail: gbribeiro@ieav.cta.br, E-mail: guimarae@ieav.cta.br, E-mail: braz@ieav.cta.br [Instituto de Estudos Avancados (IEAV), Sao Jose dos Campos, SP (Brazil). Divisao de Energia Nuclear

    2015-07-01

    Nuclear power systems turned to space electric propulsion differs strongly from usual ground-based power systems regarding the importance of overall size and weight. For propulsion power systems, weight and efficiency are essential drivers that should be managed during conception phase. Considering that, this paper aims the development of a thermal model of a closed Brayton cycle that applies the thermal conductance of heat exchangers in order to predict the energy conversion performance. The centrifugal-flow turbine and compressor characterization were achieved using algebraic equations from literature data. The binary mixture of He-Xe with molecular weight of 40 g/mole is applied and the impact of heat exchanger optimization in thermodynamic irreversibilities is evaluated in this paper. (author)

  15. Heat exchanger optimization of a closed Brayton cycle for nuclear space propulsion

    International Nuclear Information System (INIS)

    Ribeiro, Guilherme B.; Guimaraes, Lamartine N.F.; Braz Filho, Francisco A.

    2015-01-01

    Nuclear power systems turned to space electric propulsion differs strongly from usual ground-based power systems regarding the importance of overall size and weight. For propulsion power systems, weight and efficiency are essential drivers that should be managed during conception phase. Considering that, this paper aims the development of a thermal model of a closed Brayton cycle that applies the thermal conductance of heat exchangers in order to predict the energy conversion performance. The centrifugal-flow turbine and compressor characterization were achieved using algebraic equations from literature data. The binary mixture of He-Xe with molecular weight of 40 g/mole is applied and the impact of heat exchanger optimization in thermodynamic irreversibilities is evaluated in this paper. (author)

  16. Effect of Ducted HPWH on Space-Conditioning and Water Heating Energy Use -- Central Florida Lab Home

    Energy Technology Data Exchange (ETDEWEB)

    Colon, Carlos [Building America Partnership for Improved Residential Construction, Cocoa, FL (United States); Martin, Eric [Building America Partnership for Improved Residential Construction, Cocoa, FL (United States); Parker, Danny [Building America Partnership for Improved Residential Construction, Cocoa, FL (United States)

    2016-11-01

    The purpose of this research is to investigate the impact of ducted heat pump water heaters (HPWHs) on space conditioning and water heating energy use in residential applications. Two identical HPWHs, each of 60 gallon capacity were tested side by side at the Flexible Residential Test facility (FRTF) laboratories of the Florida Solar Energy Center (FSEC) campus in Cocoa, Florida. The water heating experiments were run in each test house from July 2014 until February 2015.

  17. Effect of Ducted HPWH on Space-Conditioning and Water Heating Energy Use -- Central Florida Lab Home

    Energy Technology Data Exchange (ETDEWEB)

    Colon, Carlos [Florida Solar Energy Center, Cocoa, FL (United States); Martin, Eric [Florida Solar Energy Center, Cocoa, FL (United States); Parker, Danny [Florida Solar Energy Center, Cocoa, FL (United States)

    2016-11-01

    The purpose of this research is to investigate the impact of ducted heat pump water heaters (HPWH's) on space conditioning and water heating energy use in residential applications. Two identical HPWH's, each of 60 gallon capacity were tested side by side at the Flexible Residential Test facility (FRTF) laboratories of the Florida Solar Energy Center (FSEC) campus in Cocoa, Florida. The water heating experiments were run in each test house from July 2014 until February 2015.

  18. Experimental validation of the buildings energy performance (PEC assessment methods with reference to occupied spaces heating

    Directory of Open Access Journals (Sweden)

    Cristian PETCU

    2010-01-01

    Full Text Available This paper is part of the series of pre-standardization research aimed to analyze the existing methods of calculating the Buildings Energy Performance (PEC in view of their correction of completing. The entire research activity aims to experimentally validate the PEC Calculation Algorithm as well as the comparative application, on the support of several case studies focused on representative buildings of the stock of buildings in Romania, of the PEC calculation methodology for buildings equipped with occupied spaces heating systems. The targets of the report are the experimental testing of the calculation models so far known (NP 048-2000, Mc 001-2006, SR EN 13790:2009, on the support provided by the CE INCERC Bucharest experimental building, together with the complex calculation algorithms specific to the dynamic modeling, for the evaluation of the occupied spaces heat demand in the cold season, specific to the traditional buildings and to modern buildings equipped with solar radiation passive systems, of the ventilated solar space type. The schedule of the measurements performed in the 2008-2009 cold season is presented as well as the primary processing of the measured data and the experimental validation of the heat demand monthly calculation methods, on the support of CE INCERC Bucharest. The calculation error per heating season (153 days of measurements between the measured heat demand and the calculated one was of 0.61%, an exceptional value confirming the phenomenological nature of the INCERC method, NP 048-2006. The mathematical model specific to the hourly thermal balance is recurrent – decisional with alternating paces. The experimental validation of the theoretical model is based on the measurements performed on the CE INCERC Bucharest building, within a time lag of 57 days (06.01-04.03.2009. The measurements performed on the CE INCERC Bucharest building confirm the accuracy of the hourly calculation model by comparison to the values

  19. Energy efficiency policies for space heating in EU countries: A panel data analysis for the period 1990–2010

    International Nuclear Information System (INIS)

    Ó Broin, Eoin; Nässén, Jonas; Johnsson, Filip

    2015-01-01

    Highlights: • Space heating demand between 1990 and 2010 modelled using a panel of 14 EU countries. • The impacts of 260 efficiency polices affecting space heating demand are examined. • Regulatory policies found to have had a greater success than financial or informative. • High priority should be given to regulatory policies for space heating energy goals. - Abstract: We present an empirical analysis of the more than 250 space heating-focused energy efficiency policies that have been in force at the EU and national levels in the period 1990–2010. This analysis looks at the EU-14 residential sector (Pre-2004 EU-15, excluding Luxembourg) using a panel data regression analysis on unit consumption of energy for space heating (kWh/m 2 /year). The policies are represented as a regression variable using a semi-quantitative impact estimation obtained from the MURE Policy Database. The impacts of the policies as a whole, and subdivided into financial, regulatory, and informative policies, are examined. The correlation between the actual reductions in demand and the estimated impact of regulatory policies is found to be stronger than the corresponding correlations with the respective impacts of financial policies and informative polices. Together with the well-known market barriers to energy efficiency that exist in the residential sector, these findings suggest that regulatory policy measures be given a high priority in the design of an effective pathway towards the EU-wide goals for space heating energy

  20. Infrared astronomy seeing the heat : from William Herschel to the Herschel space observatory

    CERN Document Server

    Clements, David L

    2014-01-01

    Uncover the Secrets of the Universe Hidden at Wavelengths beyond Our Optical GazeWilliam Herschel's discovery of infrared light in 1800 led to the development of astronomy at wavelengths other than the optical. Infrared Astronomy - Seeing the Heat: from William Herschel to the Herschel Space Observatory explores the work in astronomy that relies on observations in the infrared. Author David L. Clements, a distinguished academic and science fiction writer, delves into how the universe works, from the planets in our own Solar System to the universe as a whole. The book first presents the major t

  1. General-purpose heat source project and space nuclear safety fuels program. Progress report, February 1980

    International Nuclear Information System (INIS)

    Maraman, W.J.

    1980-05-01

    This formal monthly report covers the studies related to the use of 238 PuO 2 in radioisotopic power systems carried out for the Advanced Nuclear Systems and Projects Division of the Los Alamos Scientific Laboratory. The two programs involved are: General-Purpose Heat Source Development and Space Nuclear Safety and Fuels. Most of the studies discussed here are of a continuing nature. Results and conclusions described may change as the work continues. Published reference to the results cited in this report should not be made without the explicit permission of the person in charge of the work

  2. Gas-operated heat pump for monovalent space heating and tap water heating. A seizable contribution to carbon dioxide emission control; Gasbetriebene Waermepumpe zur monovalenten Raumbeheizung und Trinkwassererwaermung. Ein greifbarer Beitrag zur Reduktion der CO{sub 2}-Emissionen

    Energy Technology Data Exchange (ETDEWEB)

    Heikrodt, K.; Heckt, R. [Viessmann Werke GmbH und Co., Allendorf (Germany)

    1999-07-01

    The project had the objectives to develop a Vuilleumier heat pump for space heating and make an experimental study testing it as a heat generator for a heating system for one- and multi-family houses. Apart from monovalent operation, the following boundary conditions were defined: provision for connection to existing heating systems, even radiator heatings with 75 C/60 C, tap water heating, and air-source heat. Performance constant, manufacturing cost, freedom from maintenance, and service life were taken into consideration in the design, rating and construction of the unit. (orig.) [German] Ziel des Vorhabens war die Entwicklung einer Vuilleumier-Waermepumpe zur Raumbeheizung und deren experimentelle Untersuchung als Waermeerzeuger fuer ein Heizungssystem in Ein- und Mehrfamilienhaeusern. Als Rahmebedingungen wurden neben einer monovalenten Betriebsweise auch die moegliche Anbindung an bestehende Heizungssysteme, sogar Radiatorheizungen mit 75 C/60 C, Trinkwassererwaermung und Luft als Waermequelle festgelegt. Leistungszahl, Herstellkosten, Wartungsfreiheit und Lebensdauer wurden in Konzeption, Auslegung und Konstruktion beruecksichtigt. (orig.)

  3. The effect of aging treatment on the high temperature fatigue strength and fatigue fracture behaviour of friction welded domestic heat resisting steels (SUH3-SUS303)

    International Nuclear Information System (INIS)

    Lee, K.Y.; Oh, S.K.; Kim, H.J.

    1981-01-01

    In this study the experiment was carried out as the high temperature rotary bending fatigue testing under the condition of 700 0 C high temperature to the friction welded domestic heat resisting steels, SUH3-SUS303, which were 10 hr., 100 hr. aging heat treated at 700 0 C after solution treatment 1 hr. at 1060 0 C for the purpose of observing the effects of the high temperature fatigue strength and fatigue fracture behaviours as well as with various mechanical properties of welded joints. The results obtained are summarized as follows: 1) Through mechanical tests and microstructural examinations, the determined optimum welding conditions, rotating speed 2420 rpm, heating pressure 8 kg/mm 2 , upsetting pressure 22 kg/mm 2 , the amount of total upset 7 mm (heating time 3 sec and upsetting time 2 sec) were satisfied. 2) The solution treated material SUH3, SUS303 and SUH3-SUS303, have the highest inclination gradiant on S-N curve due to the high temperature fatigue testing for long time at 700 0 C. 3) The optimum aging time of friction welded SUH3-SUS303, has been recognized near the 10 hr. at 700 0 C after the solution treatment of 1 hr. at 1060 0 C. 4) The high temperature fatigue limits of aging treated materials were compared with those of raw material according to the extender of aging time, on 10 hr. aging, fatigue limits were increased by SUH3 75.4%, SUS303 28.5%, friction welded joints SUH3-SUS303 44.2% and 100 hr. aging the rate were 64.9%, 30.4% and 36.6% respectively. 5) The fatigue fractures occurred at the side of the base metal SUS303 of the friction welded joints SUH3-SUS303 and it is difficult to find out fractures at the friction welding interfaces. 6) The cracking mode of SUS303, SUH3-SUS303 is intergranular in any case, but SUH3 is fractured by transgranular cracking. (author)

  4. Heat pumps

    CERN Document Server

    Macmichael, DBA

    1988-01-01

    A fully revised and extended account of the design, manufacture and use of heat pumps in both industrial and domestic applications. Topics covered include a detailed description of the various heat pump cycles, the components of a heat pump system - drive, compressor, heat exchangers etc., and the more practical considerations to be taken into account in their selection.

  5. Space and Terrestrial Power System Integration Optimization Code BRMAPS for Gas Turbine Space Power Plants With Nuclear Reactor Heat Sources

    Science.gov (United States)

    Juhasz, Albert J.

    2007-01-01

    In view of the difficult times the US and global economies are experiencing today, funds for the development of advanced fission reactors nuclear power systems for space propulsion and planetary surface applications are currently not available. However, according to the Energy Policy Act of 2005 the U.S. needs to invest in developing fission reactor technology for ground based terrestrial power plants. Such plants would make a significant contribution toward drastic reduction of worldwide greenhouse gas emissions and associated global warming. To accomplish this goal the Next Generation Nuclear Plant Project (NGNP) has been established by DOE under the Generation IV Nuclear Systems Initiative. Idaho National Laboratory (INL) was designated as the lead in the development of VHTR (Very High Temperature Reactor) and HTGR (High Temperature Gas Reactor) technology to be integrated with MMW (multi-megawatt) helium gas turbine driven electric power AC generators. However, the advantages of transmitting power in high voltage DC form over large distances are also explored in the seminar lecture series. As an attractive alternate heat source the Liquid Fluoride Reactor (LFR), pioneered at ORNL (Oak Ridge National Laboratory) in the mid 1960's, would offer much higher energy yields than current nuclear plants by using an inherently safe energy conversion scheme based on the Thorium --> U233 fuel cycle and a fission process with a negative temperature coefficient of reactivity. The power plants are to be sized to meet electric power demand during peak periods and also for providing thermal energy for hydrogen (H2) production during "off peak" periods. This approach will both supply electric power by using environmentally clean nuclear heat which does not generate green house gases, and also provide a clean fuel H2 for the future, when, due to increased global demand and the decline in discovering new deposits, our supply of liquid fossil fuels will have been used up. This is

  6. Development of a coal fired pulse combustor for residential space heating. Phase I, Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1988-04-01

    This report presents the results of the first phase of a program for the development of a coal-fired residential combustion system. This phase consisted of the design, fabrication, testing, and evaluation of an advanced pulse combustor sized for residential space heating requirements. The objective was to develop an advanced pulse coal combustor at the {approximately} 100,000 Btu/hr scale that can be integrated into a packaged space heating system for small residential applications. The strategy for the development effort included the scale down of the feasibility unit from 1-2 MMBtu/hr to 100,000 Btu/hr to establish a baseline for isolating the effect of scale-down and new chamber configurations separately. Initial focus at the residential scale was concentrated on methods of fuel injection and atomization in a bare metal unit. This was followed by incorporating changes to the advanced chamber designs and testing of refractory-lined units. Multi-fuel capability for firing oil or gas as a secondary fuel was also established. Upon completion of the configuration and component testing, an optimum configuration would be selected for integrated testing of the pulse combustor unit. The strategy also defined the use of Dry Ultrafine Coal (DUC) for Phases 1 and 2 of the development program with CWM firing to be a product improvement activity for a later phase of the program.

  7. Profiling Space Heating Behavior in Chilean Social Housing: Towards Personalization of Energy Efficiency Measures

    Directory of Open Access Journals (Sweden)

    Victor Bunster

    2015-06-01

    Full Text Available Global increases in the demand for energy are imposing strong pressures over the environment while compromising the capacity of emerging economies to achieve sustainable development. In this context, implementation of effective strategies to reduce consumption in residential buildings has become a priority concern for policy makers as minor changes at the household scale can result in major energy savings. This study aims to contribute to ongoing research on energy consumer profiling by exploring the forecasting capabilities of discrete socio-economic factors that are accessible through social housing allocation systems. Accordingly, survey data gathered by the Chilean Ministry of Social Development was used identify key characteristics that may predict firewood usage for space heating purposes among potential beneficiaries of the Chilean social housing program. The analyzed data evidences strong correlations between general household characteristics and space heating behavior in certain climatic zones, suggesting that personalized delivery of energy efficiency measures can potentially increase the effectiveness of initiatives aimed towards the reduction of current patterns of consumption.

  8. Flow and heat transfer in parallel channel attached with equally-spaced ribs, 2

    International Nuclear Information System (INIS)

    Kunugi, Tomoaki; Takizuka, Takakazu

    1980-09-01

    Using a computer code for the analysis of the flow and heat transfer in a parallel channel attached with equally-spaced ribs, calculations are performed when a pitch to rib-width ratio is 7 : 1, a rib-width to rib-height ratio is 2 : 1 and a channel-height to rib-height is 3 : 1. Assuming that the fluid properties and the heat-flux at the wall of this channel are constant, characteristics of the flow and heat transfer are analyzed in the range of Reynolds number from 10 to 250. The following results are obtained: (1) The separation region behind a rib grows downstream with the increase of Reynolds number. (2) The pressure drop of ribbed channel is greater than that of the smooth channel, and increases as Reynolds number increases. (3) The mean Nusselt number of ribbed channel is about 10 - 11 at the upper wall and about 7.5 at the lower wall in the range of Reynolds number from 10 to 250. (author)

  9. Direct utilization of geothermal energy for space and water heating at Marlin, Texas. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Conover, M.F.; Green, T.F.; Keeney, R.C.; Ellis, P.F. II; Davis, R.J.; Wallace, R.C.; Blood, F.B.

    1983-05-01

    The Torbett-Hutchings-Smith Memorial Hospital geothermal heating project, which is one of nineteen direct-use geothermal projects funded principally by DOE, is documented. The five-year project encompassed a broad range of technical, institutional, and economic activities including: resource and environmental assessments; well drilling and completion; system design, construction, and monitoring; economic analyses; public awareness programs; materials testing; and environmental monitoring. Some of the project conclusions are that: (1) the 155/sup 0/F Central Texas geothermal resource can support additional geothermal development; (2) private-sector economic incentives currently exist, especially for profit-making organizations, to develop and use this geothermal resource; (3) potential uses for this geothermal resource include water and space heating, poultry dressing, natural cheese making, fruit and vegetable dehydrating, soft-drink bottling, synthetic-rubber manufacturing, and furniture manufacturing; (4) high maintenance costs arising from the geofluid's scaling and corrosion tendencies can be avoided through proper analysis and design; (5) a production system which uses a variable-frequency drive system to control production rate is an attractive means of conserving parasitic pumping power, controlling production rate to match heating demand, conserving the geothermal resource, and minimizing environmental impacts.

  10. Large-size deployable construction heated by solar irradiation in free space

    Science.gov (United States)

    Pestrenina, Irena; Kondyurin, Alexey; Pestrenin, Valery; Kashin, Nickolay; Naymushin, Alexey

    Large-size deployable construction in free space with subsequent direct curing was invented more than fifteen years ago (Briskman et al., 1997 and Kondyurin, 1998). It caused a lot of scientific problems, one of which is a possibility to use the solar energy for initiation of the curing reaction. This paper is devoted to investigate the curing process under sun irradiation during a space flight in Earth orbits. A rotation of the construction is considered. This motion can provide an optimal temperature distribution in the construction that is required for the polymerization reaction. The cylindrical construction of 80 m length with two hemispherical ends of 10 m radius is considered. The wall of the construction of 10 mm carbon fibers/epoxy matrix composite is irradiated by heat flux from the sun and radiates heat from the external surface by the Stefan- Boltzmann law. A stage of polymerization reaction is calculated as a function of temperature/time based on the laboratory experiments with certified composite materials for space exploitation. The curing kinetics of the composite is calculated for different inclination Low Earth Orbits (300 km altitude) and Geostationary Earth Orbit (40000 km altitude). The results show that • the curing process depends strongly on the Earth orbit and the rotation of the construction; • the optimal flight orbit and rotation can be found to provide the thermal regime that is sufficient for the complete curing of the considered construction. The study is supported by RFBR grant No.12-08-00970-a. 1. Briskman V., A.Kondyurin, K.Kostarev, V.Leontyev, M.Levkovich, A.Mashinsky, G.Nechitailo, T.Yudina, Polymerization in microgravity as a new process in space technology, Paper No IAA-97-IAA.12.1.07, 48th International Astronautical Congress, October 6-10, 1997, Turin Italy. 2. Kondyurin A.V., Building the shells of large space stations by the polymerisation of epoxy composites in open space, Int. Polymer Sci. and Technol., v.25, N4

  11. District space heating potential of low temperature hydrothermal geothermal resources in the southwestern United States. Technical report

    Energy Technology Data Exchange (ETDEWEB)

    McDevitt, P.K.; Rao, C.R.

    1978-10-01

    A computer simulation model (GIRORA-Nonelectric) is developed to study the economics of district space heating using geothermal energy. GIRORA-Nonelectric is a discounted cashflow investment model which evaluates the financial return on investment for space heating. This model consists of two major submodels: the exploration for and development of a geothermal anomaly by a geothermal producer, and the purchase of geothermal fluid by a district heating unit. The primary output of the model is a calculated rate of return on investment earned by the geothermal producer. The results of the sensitivity analysis of the model subject to changes in physical and economic parameters are given in this report. Using the results of the economic analysis and technological screening criteria, all the low temperature geothermal sites in Southwestern United States are examined for economic viability for space heating application. The methodology adopted and the results are given.

  12. Solar Heating and Cooling of Residential Buildings: Sizing, Installation and Operation of Systems.

    Science.gov (United States)

    Colorado State Univ., Ft. Collins. Solar Energy Applications Lab.

    This training course and a companion course titled "Design of Systems for Solar Heating and Cooling of Residential Buildings," are designed to train home designers and builders in the fundamentals of solar hydronic and air systems for space heating and cooling and domestic hot water heating for residential buildings. Each course, organized in 22…

  13. Instantaneous Metabolic Cost of Walking: Joint-Space Dynamic Model with Subject-Specific Heat Rate.

    Directory of Open Access Journals (Sweden)

    Dustyn Roberts

    Full Text Available A subject-specific model of instantaneous cost of transport (ICOT is introduced from the joint-space formulation of metabolic energy expenditure using the laws of thermodynamics and the principles of multibody system dynamics. Work and heat are formulated in generalized coordinates as functions of joint kinematic and dynamic variables. Generalized heat rates mapped from muscle energetics are estimated from experimental walking metabolic data for the whole body, including upper-body and bilateral data synchronization. Identified subject-specific energetic parameters-mass, height, (estimated maximum oxygen uptake, and (estimated maximum joint torques-are incorporated into the heat rate, as opposed to the traditional in vitro and subject-invariant muscle parameters. The total model metabolic energy expenditure values are within 5.7 ± 4.6% error of the measured values with strong (R2 > 0.90 inter- and intra-subject correlations. The model reliably predicts the characteristic convexity and magnitudes (0.326-0.348 of the experimental total COT (0.311-0.358 across different subjects and speeds. The ICOT as a function of time provides insights into gait energetic causes and effects (e.g., normalized comparison and sensitivity with respect to walking speed and phase-specific COT, which are unavailable from conventional metabolic measurements or muscle models. Using the joint-space variables from commonly measured or simulated data, the models enable real-time and phase-specific evaluations of transient or non-periodic general tasks that use a range of (aerobic energy pathway similar to that of steady-state walking.

  14. Space monitoring of the earth on the presence of solid domestic wastes using a discrete orthogonal transforms

    Directory of Open Access Journals (Sweden)

    Kazaryan Maretta

    2017-01-01

    Full Text Available The paper investigates multivariate Wavelet Haar’s series. To study on the correctness is made by means of Tikhonov’s method. A theorem on stability and uniform convergence of a regularized summable function of the wavelet-Haar’s series functions in Lipschitz class with approximate coefficients is proved. An experiment confirms the validity of Tikhonov’s method using space monitoring of waste disposal facilities is conducted as an example. Namely, the decoding of space images-images using N-dimensional Haar’s wavelet transform is used.

  15. Optimization of operating parameters of ground source heat pump system for space heating and cooling by Taguchi method and utility concept

    International Nuclear Information System (INIS)

    Sivasakthivel, T.; Murugesan, K.; Thomas, H.R.

    2014-01-01

    Highlights: • Ground Source Heat Pump (GSHP) technology is suitable for both heating and cooling. • Important parameters that affect the GSHP performance has been listed. • Parameters of GSHP system has been optimized for heating and cooling mode. • Taguchi technique and utility concept are developed for GSHP optimization. - Abstract: Use of ground source energy for space heating applications through Ground Source Heat pump (GSHP) has been established as an efficient thermodynamic process. The electricity input to the GSHP can be reduced by increasing the COP of the system. However, the COP of a GSHP system will be different for heating and cooling mode operations. Hence in order to reduce the electricity input to the GSHP, an optimum value of COP has to be determined when GSHP is operated in both heating and cooling modes. In the present research, a methodology is proposed to optimize the operating parameters of a GSHP system which will operate on both heating and cooling modes. Condenser inlet temperature, condenser outlet temperature, dryness fraction at evaporator inlet and evaporator outlet temperature are considered as the influencing parameters of the heat pump. Optimization of these parameters for only heating or only cooling mode operation is achieved by employing Taguchi method for three level variations of the above parameters using an L 9 (3 4 ) orthogonal array. Higher the better concept has been used to get a higher COP. A computer program in FORTAN has been developed to carry out the computations and the results have been analyzed for the optimum conditions using Signal-to-Noise (SN) ratio and Analysis Of Variance (ANOVA) method. Based on this analysis, the maximum COP for only heating and only cooling operation are obtained as 4.25 and 3.32 respectively. By making use of the utility concept both the higher values of COP obtained for heating and cooling modes are optimized to get a single optimum COP for heating and cooling modes. A single

  16. Experimental Space Shuttle Orbiter Studies to Acquire Data for Code and Flight Heating Model Validation

    Science.gov (United States)

    Wadhams, T. P.; Holden, M. S.; MacLean, M. G.; Campbell, Charles

    2010-01-01

    In an experimental study to obtain detailed heating data over the Space Shuttle Orbiter, CUBRC has completed an extensive matrix of experiments using three distinct models and two unique hypervelocity wind tunnel facilities. This detailed data will be employed to assess heating augmentation due to boundary layer transition on the Orbiter wing leading edge and wind side acreage with comparisons to computational methods and flight data obtained during the Orbiter Entry Boundary Layer Flight Experiment and HYTHIRM during STS-119 reentry. These comparisons will facilitate critical updates to be made to the engineering tools employed to make assessments about natural and tripped boundary layer transition during Orbiter reentry. To achieve the goals of this study data was obtained over a range of Mach numbers from 10 to 18, with flight scaled Reynolds numbers and model attitudes representing key points on the Orbiter reentry trajectory. The first of these studies were performed as an integral part of Return to Flight activities following the accident that occurred during the reentry of the Space Shuttle Columbia (STS-107) in February of 2003. This accident was caused by debris, which originated from the foam covering the external tank bipod fitting ramps, striking and damaging critical wing leading edge heating tiles that reside in the Orbiter bow shock/wing interaction region. During investigation of the accident aeroheating team members discovered that only a limited amount of experimental wing leading edge data existed in this critical peak heating area and a need arose to acquire a detailed dataset of heating in this region. This new dataset was acquired in three phases consisting of a risk mitigation phase employing a 1.8% scale Orbiter model with special temperature sensitive paint covering the wing leading edge, a 0.9% scale Orbiter model with high resolution thin-film instrumentation in the span direction, and the primary 1.8% scale Orbiter model with detailed

  17. 14 CFR 121.342 - Pitot heat indication systems.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Pitot heat indication systems. 121.342... REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Instrument and Equipment Requirements § 121.342 Pitot... a flight instrument pitot heating system unless the airplane is also equipped with an operable pitot...

  18. 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.

  19. Electric space heating scheduling for real-time explicit power control in active distribution networks

    DEFF Research Database (Denmark)

    Costanzo, Giuseppe Tommaso; Bernstein, Andrey; Chamorro, Lorenzo Reyes

    2015-01-01

    This paper presents a systematic approach for abstracting the flexibility of a building space heating system and using it within a composable framework for real-time explicit power control of microgrids and, more in general, active distribution networks. In particular, the proposed approach...... is developed within the context of a previously defined microgrid control framework, called COMMELEC, conceived for the explicit and real-time control of these specific networks. The designed control algorithm is totally independent from the need of a building model and allows exploiting the intrinsic thermal...... inertia for real-time control. The paper first discusses the general approach, then it proves its validity via dedicated simulations performed on specific case study composed by the CIGRE LV microgrid benchmark proposed by the Cigré TF C6.04.02....

  20. Compact seasonal PCM heat storage for solar heating systems

    DEFF Research Database (Denmark)

    Dannemand, Mark

    Space heating of buildings and preparation of domestic hot water accounts for a large part of the society’s energy consumption. Solar radiation is an abundant and renewable energy source which can be harvested by solar collectors and used to cover heating demands in the built environment....... The seasonal availability of solar energy does however not match with the heating demands in buildings which typically are large in winter periods when limited solar energy is available. Heat can be stored over a few days in water stores but continuous heat losses limits the storage periods. The possibility...... of storing heat from summer where solar energy is widely available to winter periods where the heating demands are large, allows for implementing more renewable energy in our energy system. The phase change material (PCM) sodium acetate trihydrate (SAT) melts at 58 °C. The melting process requires...

  1. “Let’s Take a Look Together”: Walking Interviews in Domestic Spaces as a Means to Examine ICT Experiences of Women 60+

    Directory of Open Access Journals (Sweden)

    Barbara Ratzenböck

    2016-06-01

    Full Text Available Although mobile methods are becoming more common within the social sciences (e.g. Ricketts Hein et al., 2008 and Wiederhold, 2015, p. 607, they mostly take place outdoors. This paper examines the potential of walking interviews conducted in small domestic spaces to explore the ICT experiences of women aged 60+ and to discuss the challenges and advantages of this method. This case study of indoor walking interview material is a part of a larger research project on the ICT experiences of women 60+ in the Austrian province of Styria. The advantages and challenges of conducting walking interviews in the homes of interviewees are identified and explored. As this case study demonstrates, walking interviews in homes give the researcher a glimpse into the private areas of everyday life, let the interviewees lead the researcher through the space, allow the participants to conduct the conversation, and thus invite a reflection on the power dynamics inherent in the interview situation. This method also compares the statements provided by participants in semi-structured interviews with the information gathered through an encounter with media and ICTs in the home. These comparisons yield a variety of insights on prior statements through the addition of emphases, “contradictions,” or minimizing the importance of previous interview statements. Moreover, interactions with the objects in the home that are encountered during the walking interview also provide important “prompts” to stimulate a detailed and multifaceted discussion of everyday life experiences with ICTs and other media.

  2. The exploitation of biomass for building space heating in Greece: Energy, environmental and economic considerations

    International Nuclear Information System (INIS)

    Michopoulos, A.; Skoulou, V.; Voulgari, V.; Tsikaloudaki, A.; Kyriakis, N.A.

    2014-01-01

    Highlights: • The oil substitution with biomass residues for heating buildings is examined. • Primary energy consumption from biomass results increased by 3–4% as compared to diesel oil. • CO 2 and SO 2 emissions are significantly higher with biomass than with diesel oil. • The examined substitution is economically attractive for the final consumers. - Abstract: The exploitation of forest and agricultural biomass residues for energy production may offer significant advantages to the energy policy of the relevant country, but it strongly depends on a number of financial, technological and political factors. The work in hand focuses on the investigation of the energy, environmental and financial benefits, resulting from the exploitation of forest and agricultural biomass residues, fully substituting the conventional fuel (diesel oil) for building space heating in Greece. For this investigation, the energy needs of a representative building are determined using the EnergyPlus software, assuming that the building is located across the various climate zones of Greece. Based on the resulting thermal energy needs, the primary energy consumption and the corresponding emissions are determined, while an elementary fiscal analysis is also performed. The results show that significant financial benefits for the end-user are associated with the substitution examined, even though increased emissions and primary energy consumption have been derived

  3. The impact of consumer behavior on residential energy demand for space heating

    Energy Technology Data Exchange (ETDEWEB)

    Haas, R.; Auer, H.; Biermayr, P. [Vienna Univ. of Technology (Austria). Inst. of Energy Economics

    1998-04-01

    Besides technical parameters, consumer behavior is the most important issue with respect to energy consumption in households. In this paper, the results of a cross-section analysis of Austrian households are presented. The impact of the following parameters on residential energy demand for space heating have been investigated: (i) thermal quality of buildings; (ii) consumer behavior; (iii) heating degree days; (iv) building type (single- or multi-family dwellings). The result of this investigation provides evidence of a rebound-effect of about 15 to 30% due to building retrofit. This leads to the conclusion that energy savings achieved in practice (and straightforward the reduction in CO{sub 2} emissions) due to energy conservation measures will be lower than those calculated in engineering conservation studies. Straightforward, the most important conclusions for energy policy makers are: (i) Standards, building codes, respectively, are important tools to increase the thermal quality of new buildings; and (ii) Due to prevailing low energy prices, a triggering tool has to be implemented which may be rebates or loans. (orig.)

  4. Experimental determination of convective heat transfer coefficients in the separated flow region of the Space Shuttle Solid Rocket Motor

    Science.gov (United States)

    Whitesides, R. Harold; Majumdar, Alok K.; Jenkins, Susan L.; Bacchus, David L.

    1990-01-01

    A series of cold flow heat transfer tests was conducted with a 7.5-percent scale model of the Space Shuttle Rocket Motor (SRM) to measure the heat transfer coefficients in the separated flow region around the nose of the submerged nozzle. Modifications were made to an existing 7.5 percent scale model of the internal geometry of the aft end of the SRM, including the gimballed nozzle in order to accomplish the measurements. The model nozzle nose was fitted with a stainless steel shell with numerous thermocouples welded to the backside of the thin wall. A transient 'thin skin' experimental technique was used to measure the local heat transfer coefficients. The effects of Reynolds number, nozzle gimbal angle, and model location were correlated with a Stanton number versus Reynolds number correlation which may be used to determine the convective heating rates for the full scale Space Shuttle Solid Rocket Motor nozzle.

  5. Forced heat convection in annular spaces; Convection forcee de la chaleur dans les espaces annulaires

    Energy Technology Data Exchange (ETDEWEB)

    Pelce, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1960-02-15

    This report deals with the experimental study of forced heat convection in annular spaces through which flow of air is passing when a uniform heat flux is dissipated across the inner wall. These observations took place chiefly in the region where thermal equilibrium are not yet established. Amongst other things it became apparent that, both in the region where thermal equilibrium conditions are on the way to establishment and where they are already established, the following relationship held good: the longitudinal temperature gradient, either on the wall or in the fluid stream, is proportional to the heat flux dissipated q, and inversely proportional to the average flow rate V: dT/dx = B (q/V). From this result the next step is to express the variations of the local convection coefficient {alpha} (or of the Margoulis number M) in a relationship of the form: 1/M = {psi}(V) + F(x). If this relationship is compared with the classical empirical relationship {alpha} = KV{sup n} (where n is close to 0.8), the relationship: 1/M = {xi}V{sup 1-n} + F(x) is obtained ({xi} is a constant for a given annular space); from this it was possible to coordinate the whole set of experimental results. (author) [French] Il s'agit precisement de l'etude experimentale de la convection forcee de la chaleur dans des espaces annulaires parcourus par de l'air en ecoulement turbulent, lorsqu'on dissipe a travers la paroi interieure un flux de chaleur uniforme. Ces observations ont eu lieu principalement dans la region ou le regime thermique n'est pas encore etabli. Il est apparu, entre autre, qu'il existait, tant dans la region ou le regime thermique est en voie d'etablissement qu'en regime etabli, la relation suivante: le gradient longitudinal des temperatures, que ce soit sur la paroi ou dans l'ecoulement fluide, est proportionnel au flux de la chaleur dissipee q, et inversement proportionnel a la vitesse moyenne V de l'ecoulement: dT/dx = B (q/V). Ce resultat a pour consequence de traduire

  6. Evaluation and demonstration of decentralized space and water heating versus centralized services for new and rehabilitated multifamily buildings. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Belkus, P. [Foster-Miller, Inc., Waltham, MA (US); Tuluca, A. [Steven Winter Associates, Inc., Norwalk, CT (US)

    1993-06-01

    The general objective of this research was aimed at developing sufficient technical and economic know-how to convince the building and design communities of the appropriateness and energy advantages of decentralized space and water heating for multifamily buildings. Two main goals were established to guide this research. First, the research sought to determine the cost-benefit advantages of decentralized space and water heating versus centralized systems for multifamily applications based on innovative gas piping and appliance technologies. The second goal was to ensure that this information is made available to the design community.

  7. Domestic violence

    OpenAIRE

    Kiurski Jasmina

    2003-01-01

    Since the 1960s, there has been growing awareness regarding the issue of domestic violence as a form of violence against women, which has been largely influenced by the work of feminist activist and scholars in North America and Europe (Dobash and Dobash 1992). Other terms have been used to describe the same phenomenon, including domestic abuse, spousal abuse, wife battering, marital violence, intimate partner violence. Though there is no doubt that this problem has existed for much more than...

  8. High temperature thermoacoustic heat pump

    Energy Technology Data Exchange (ETDEWEB)

    Tijani, H.; Spoelstra, S. [Energy research Centre of the Netherlands, 1755 ZG Petten (Netherlands)

    2012-06-15

    Thermoacoustic technology can provide new types of heat pumps that can be deployed in different applications. A thermoacoustic heat pumps can for example be applied in dwellings to generate cooling or heating. Typically, space and water heating makes up about 60% of domestics and offices energy consumption. The application of heat pumps can contribute to achieve energy savings and environmental benefits by reducing CO2 and NOx emissions. This paper presents the study of a laboratory scale thermoacoustic-Stirling heat pump operating between 10C and 80C which can be applied in domestics and offices. The heat pump is driven by a thermoacoustic-Stirling engine. The experimental results show that the heat pump pumps 250 W of heat at 60C at a drive ratio of 3.6% and 200 W at 80C at a drive ratio of 3.5 %. The performance for both cases is about 40% of the Carnot performance. The design, construction, and performance measurements of the heat pump will be presented and discussed.

  9. High Temperature Thermoacoustic Heat Pump

    Energy Technology Data Exchange (ETDEWEB)

    Tijani, H.; Spoelstra, S. [ECN Biomass and Energy Efficiency, Petten (Netherlands)

    2012-07-15

    Thermoacoustic technology can provide new types of heat pumps that can be deployed in different applications. Thermoacoustic heat pumps can for example be applied in dwellings to generate cooling or heating. Typically, space and water heating makes up about 60% of domestic and office energy consumption. The application of heat pumps can contribute to achieve energy savings and environmental benefits by reducing CO2 and NOx emissions. This paper presents the study of a laboratory scale thermoacoustic-Stirling heat pump operating between 10C and 80C which can be applied in domestics and offices. The heat pump is driven by a thermoacoustic-Stirling engine. The experimental results show that the heat pump pumps 250 W of heat at 60C at a drive ratio of 3.6 % and 200 W at 80C at a drive ratio of 3.5 %. The performance for both cases is about 40% of the Carnot performance. The design, construction, and performance measurements of the heat pump will be presented and discussed.

  10. Heat and mass transfer across gas-filled enclosed spaces between a hot liquid surface and a cooled roof

    Energy Technology Data Exchange (ETDEWEB)

    Ralph, J C; Bennett, A W [Atomic Energy Research Establishment, Harwell, Oxfordshire (United Kingdom)

    1977-01-01

    A detailed knowledge is required of the amounts of sodium vapour which may be transported from the hot surface of a fast reactor coolant pool through the cover gas to cooler regions of the structure. Evaporation from the unbounded liquid surfaces of lakes and seas has been studied extensively but the heat and mass transfer mechanisms in gas-vapour mixtures which occur in enclosed spaces have received less attention. Recent work at Harwell has provided a theoretical model from which the heat and mass transfer in idealised plane cavities can be calculated. An experimental study is reported in this paper which seeks to verify the theoretical prediction. Heat and mass transfer measurements have been made on a system in which a heated water pool transfers heat and mass across a gas-filled space to a cooled horizontal cover plate. Several cover gases were used in the experiments and the results show that, provided the partial density of the vapour is low compared with that of the gas, the heat transfer mechanism is that of combined convection and radiation. The enhancement in heat transfer due to the presence of the vapour is broadly consistent with assumption of a direct analogy between heat and mass transfer neglecting condensation in the interspace. The mass transfer measurements, in which water condensing on the cooled roof was measured directly, showed for low roof temperatures an imbalance between the mass and heat transfer. This observation is consistent with the theoretical predictions that heat transfer in the convecting system should be independent of the amount of condensation and 'rain-back' within the cavity. The results of tests with helium showed that convection was entirely suppressed by the presence of the water vapour. This confirms the behaviour predicted for gas-vapour mixtures in which the vapour density is of the same order as the gas density. (author)

  11. Modeling of Rocket Fuel Heating and Cooling Processes in the Interior Receptacle Space of Ground-Based Systems

    Directory of Open Access Journals (Sweden)

    K. I. Denisova

    2016-01-01

    Full Text Available The propellant to fill the fuel tanks of the spacecraft, upper stages, and space rockets on technical and ground-based launch sites before fueling should be prepared to ensure many of its parameters, including temperature, in appropriate condition. Preparation of fuel temperature is arranged through heating and cooling the rocket propellants (RP in the tanks of fueling equipment. Processes of RP temperature preparation are the most energy-intensive and timeconsuming ones, which require that a choice of sustainable technologies and modes of cooling (heating RP provided by the ground-based equipment has been made through modeling of the RP [1] temperature preparation processes at the stage of design and operation of the groundbased fueling equipment.The RP temperature preparation in the tanks of the ground-based systems can be provided through the heat-exchangers built-in the internal space and being external with respect to the tank in which antifreeze, air or liquid nitrogen may be used as the heat transfer media. The papers [1-12], which note a promising use of the liquid nitrogen to cool PR, present schematic diagrams and modeling systems for the RP temperature preparation in the fueling equipment of the ground-based systems.We consider the RP temperature preparation using heat exchangers to be placed directly in RP tanks. Feeding the liquid nitrogen into heat exchanger with the antifreeze provides the cooling mode of PR while a heated air fed there does that of heating. The paper gives the systems of equations and results of modeling the processes of RP temperature preparation, and its estimated efficiency.The systems of equations of cooling and heating RP are derived on the assumption that the heat exchange between the fuel and the antifreeze, as well as between the storage tank and the environment is quasi-stationary.The paper presents calculation results of the fuel temperature in the tank, and coolant temperature in the heat exchanger, as

  12. Analysis of a radiative heat exchanger for systems for thermal control of space vehicles

    International Nuclear Information System (INIS)

    Vasil'ev, L.L.; Kanonchik, L.E.; Babenko, V.A.

    1995-01-01

    Starting from the solution of a two-dimensional heat conduction problem, a mathematical model of a heat pipe-based radiative heat exchanger is developed. Good agreement between the predicted and experimental results is obtained. The effect of operational and structural parameters on the characteristics of the radiative heat exchanger is analyzed

  13. Simulation Study of the Energy Performance of Different Space Heating Methods in Plus-energy Housing

    DEFF Research Database (Denmark)

    Schøtt, Jacob; Andersen, Mads E.; Kazanci, Ongun Berk

    2016-01-01

    Due to a shortage of energy resources, the focus on indoor environment and energy use in buildings is increasing which sets higher standards for the performance of HVAC systems in buildings. The variety of available heating systems for both residential buildings and office buildings is therefore...... cases the heat source was a natural gas fired condensing boiler, and for the floor heating cases also an air-to-water heat pump was used to compare two heat sources. The systems were also compared in terms of auxiliary energy use for pumps and fans. The results show that the investigated floor heating...... from the low temperature heating potential since an increased floor covering requires higher average water temperatures in the floor loops and decreases the COP of the heat pump. The water-based heating systems required significantly less auxiliary energy input compared to the air-based heating system...

  14. Energy-efficient and cost-effective in-house substations bypass for improving thermal and DHW (domestic hot water) comfort in bathrooms in low-energy buildings supplied by low-temperature district heating

    DEFF Research Database (Denmark)

    Brand, Marek; Dalla Rosa, Alessandro; Svendsen, Svend

    2014-01-01

    temperature and additional cooling of bypass water by 3.9 °C, reducing the heat loss from the DH network by 13% and covering 40% of the heat used in the bathroom FH. The use of the bypass flow in bathroom FH is a cost-effective solution exploiting the heat that would otherwise be lost in the DH network......Using a bypass to redirect a small flow through the in-house DH (district heating) substation directly to the return pipe is a commonly used but energy-inefficient solution to keep the DH network “warm” during non-heating seasons. Instead, this water can be redirected to the bathroom FH (floor...... heating) to cool down further and thus reduce the heat lost from bypass operation while tempering the bathroom floor and guaranteeing fast provision of DHW (domestic hot water). We used the commercial software IDA-ICE to model a reference building where we implemented various solutions for controlling...

  15. Geothermal heat pumps - Trends and comparisons

    Energy Technology Data Exchange (ETDEWEB)

    Lund, John W

    1989-01-01

    Heat pumps are used where geothermal water or ground temperatures are only slightly above normal, generally 50 to 90 deg. F. Conventional geothermal heating (and cooling) systems are not economically efficient at these temperatures. Heat pumps, at these temperatures, can provide space heating and cooling, and with a desuperheater, domestic hot water. Two basic heat pump systems are available, air-source and water- or ground-source. Water- and ground-coupled heat pumps, referred to as geothermal heat pumps (GHP), have several advantages over air-source heat pumps. These are: (1) they consume about 33% less annual energy, (2) they tap the earth or groundwater, a more stable energy source than air, (3) they do not require supplemental heat during extreme high or low outside temperatures, (4) they use less refrigerant (freon), and (5) they have a simpler design and consequently less maintenance.

  16. Megawatt Class Nuclear Space Power Systems (MCNSPS) conceptual design and evaluation report. Volume 2, technologies 1: Reactors, heat transport, integration issues

    Science.gov (United States)

    Wetch, J. R.

    1988-01-01

    The objectives of the Megawatt Class Nuclear Space Power System (MCNSPS) study are summarized and candidate systems and subsystems are described. Particular emphasis is given to the heat rejection system and the space reactor subsystem.

  17. Renewable Heating And Cooling

    Science.gov (United States)

    Renewable heating and cooling is a set of alternative resources and technologies that can be used in place of conventional heating and cooling technologies for common applications such as water heating, space heating, space cooling and process heat.

  18. A Computational Fluid Dynamic and Heat Transfer Model for Gaseous Core and Gas Cooled Space Power and Propulsion Reactors

    Science.gov (United States)

    Anghaie, S.; Chen, G.

    1996-01-01

    A computational model based on the axisymmetric, thin-layer Navier-Stokes equations is developed to predict the convective, radiation and conductive heat transfer in high temperature space nuclear reactors. An implicit-explicit, finite volume, MacCormack method in conjunction with the Gauss-Seidel line iteration procedure is utilized to solve the thermal and fluid governing equations. Simulation of coolant and propellant flows in these reactors involves the subsonic and supersonic flows of hydrogen, helium and uranium tetrafluoride under variable boundary conditions. An enthalpy-rebalancing scheme is developed and implemented to enhance and accelerate the rate of convergence when a wall heat flux boundary condition is used. The model also incorporated the Baldwin and Lomax two-layer algebraic turbulence scheme for the calculation of the turbulent kinetic energy and eddy diffusivity of energy. The Rosseland diffusion approximation is used to simulate the radiative energy transfer in the optically thick environment of gas core reactors. The computational model is benchmarked with experimental data on flow separation angle and drag force acting on a suspended sphere in a cylindrical tube. The heat transfer is validated by comparing the computed results with the standard heat transfer correlations predictions. The model is used to simulate flow and heat transfer under a variety of design conditions. The effect of internal heat generation on the heat transfer in the gas core reactors is examined for a variety of power densities, 100 W/cc, 500 W/cc and 1000 W/cc. The maximum temperature, corresponding with the heat generation rates, are 2150 K, 2750 K and 3550 K, respectively. This analysis shows that the maximum temperature is strongly dependent on the value of heat generation rate. It also indicates that a heat generation rate higher than 1000 W/cc is necessary to maintain the gas temperature at about 3500 K, which is typical design temperature required to achieve high

  19. Energy Efficiency and Sustainability Evaluation of Space and Water Heating in Urban Residential Buildings of the Hot Summer and Cold Winter Zone in China

    Directory of Open Access Journals (Sweden)

    Xiao Chen

    2016-09-01

    Full Text Available With the urbanization process of the hot summer and cold winter (HSCW zone in China, the energy consumption of space and water heating in urban residential buildings of the HSCW zone has increased rapidly. This study presents the energy efficiency and sustainability evaluation of various ways of space and water heating taking 10 typical cities in the HSCW zone as research cases. Two indicators, primary energy efficiency (PEE and sustainability index based on exergy efficiency, are adopted to perform the evaluation. Models for the energy and total exergy efficiencies of various space and water heating equipment/systems are developed. The evaluation results indicate that common uses of electricity for space and water heating are the most unsustainable ways of space and water heating. In terms of PEE and sustainability index, air-source heat pumps for space and water heating are suitable for the HSCW zone. The PEE and sustainability index of solar water heaters with auxiliary electric heaters are greatly influenced by local solar resources. Air-source heat pump assisted solar hot water systems are the most sustainable among all water heating equipment/systems investigated in this study. Our works suggest the key potential for improving the energy efficiency and the sustainability of space and water heating in urban residential buildings of the HSCW zone.

  20. General-purpose heat source project and space nuclear safety and fuels program. Progress report

    International Nuclear Information System (INIS)

    Maraman, W.J.

    1980-02-01

    Studies related to the use of 238 PuO 2 in radioisotopic power systems carried out for the Advanced Nuclear Systems and Projects Division of LASL are presented. The three programs involved are: general-purpose heat source development; space nuclear safety; and fuels program. Three impact tests were conducted to evaluate the effects of a high temperature reentry pulse and the use of CBCF on impact performance. Additionally, two 238 PuO 2 pellets were encapsulated in Ir-0.3% W for impact testing. Results of the clad development test and vent testing are noted. Results of the environmental tests are summarized. Progress on the Stirling isotope power systems test and the status of the improved MHW tests are indicated. The examination of the impact failure of the iridium shell of MHFT-65 at a fuel pass-through continued. A test plan was written for vibration testing of the assembled light-weight radioisotopic heater unit. Progress on fuel processing is reported

  1. Space Launch System Base Heating Test: Environments and Base Flow Physics

    Science.gov (United States)

    Mehta, Manish; Knox, Kyle S.; Seaford, C. Mark; Dufrene, Aaron T.

    2016-01-01

    The NASA Space Launch System (SLS) vehicle is composed of four RS-25 liquid oxygen- hydrogen rocket engines in the core-stage and two 5-segment solid rocket boosters and as a result six hot supersonic plumes interact within the aft section of the vehicle during ight. Due to the complex nature of rocket plume-induced ows within the launch vehicle base during ascent and a new vehicle con guration, sub-scale wind tunnel testing is required to reduce SLS base convective environment uncertainty and design risk levels. This hot- re test program was conducted at the CUBRC Large Energy National Shock (LENS) II short-duration test facility to simulate ight from altitudes of 50 kft to 210 kft. The test program is a challenging and innovative e ort that has not been attempted in 40+ years for a NASA vehicle. This presentation discusses the various trends of base convective heat ux and pressure as a function of altitude at various locations within the core-stage and booster base regions of the two-percent SLS wind tunnel model. In-depth understanding of the base ow physics is presented using the test data, infrared high-speed imaging and theory. The normalized test design environments are compared to various NASA semi- empirical numerical models to determine exceedance and conservatism of the ight scaled test-derived base design environments. Brief discussion of thermal impact to the launch vehicle base components is also presented.

  2. Environmental benefits of domestic solar energy systems

    International Nuclear Information System (INIS)

    Kalogirou, Soteris A.

    2004-01-01

    All nations of the world depend on fossil fuels for their energy needs. However the obligation to reduce CO 2 and other gaseous emissions in order to be in conformity with the Kyoto agreement is the reason behind which countries turn to non-polluting renewable energy sources. In this paper the pollution caused by the burning of fossil fuels is initially presented followed by a study on the environmental protection offered by the two most widely used renewable energy systems, i.e. solar water heating and solar space heating. The results presented in this paper show that by using solar energy, considerable amounts of greenhouse polluting gasses are avoided. For the case of a domestic water heating system, the saving, compared to a conventional system, is about 80% with electricity or Diesel backup and is about 75% with both electricity and Diesel backup. In the case of space heating and hot water system the saving is about 40%. It should be noted, however, that in the latter, much greater quantities of pollutant gasses are avoided. Additionally, all systems investigated give positive and very promising financial characteristics. With respect to life cycle assessment of the systems, the energy spent for manufacture and installation of the solar systems is recouped in about 1.2 years, whereas the payback time with respect to emissions produced from the embodied energy required for the manufacture and installation of the systems varies from a few months to 9.5 years according to the fuel and the particular pollutant considered. Moreover, due to the higher solar contribution, solar water heating systems have much shorter payback times than solar space heating systems. It can, therefore, be concluded that solar energy systems offer significant protection to the environment and should be employed whenever possible in order to achieve a sustainable future

  3. Validation of a simulation method for forced circulation type of solar domestic hot water heating systems; Kyosei junkangata taiyonetsu kyuto system simulation hoho no kensho

    Energy Technology Data Exchange (ETDEWEB)

    Sato, M; Udagawa, M [Kogakuin University, Tokyo (Japan); Matsumoto, T [Yazaki Corp., Tokyo (Japan)

    1996-10-27

    Simulation of solar hot water systems using element model was conducted, in which computation of the convergence of apparatus characteristic values was performed every hour. For each apparatus, the outlet temperature was made a function of the inlet temperature on the basis of the heat balance, from which a simultaneous equation was derived and then solved for the determination of the outlet temperature for the computation of the quantity of heat collected by each apparatus. The actually measured system comprises a planar solar collector, heat storage tank, and heat collector piping. The measurement involved a direct heat collecting system with the medium running from the heat storage tank bottom layer, through the solar collector, and then back to the heat storage tank third layer, and an indirect heat collector system with a heat exchanger provided at the heat storage tank bottom layer. There was no substantial difference between the direct type and the indirect type with respect to the solar collector inlet and outlet temperatures, quantity of heat collected, and the fluctuation in heat storage tank inside temperature distribution relative to time. Difference occurred between the two in tank water temperature distribution, however, when water was extracted in great volume at a time. The quantity of the heat collected by each of the two and the daily integration of the same differed but a little from computed values. 4 refs., 6 figs., 4 tabs.

  4. New operational spaces for the electron cyclotron resonance heating at ASDEX upgrade

    International Nuclear Information System (INIS)

    Hoehnle, Hendrik Sebastian

    2012-01-01

    In this thesis, new electron cyclotron resonance heating (ECRH) scenarios were developed for an extension of the operational space at the tokamak ASDEX Upgrade in view of ITER compatibility. In the last years, the first wall material at ASDEX Upgrade was changed from graphite to tungsten, and the ECRH is needed to control the tungsten concentration in the plasma core. But, in ITER-like plasma discharges at ASDEX Upgrade, the usage of the ECRH in the typically used second harmonic extraordinary polarised mode (X2 mode) is limited. In these ITER-scenarios a small safety factor should be achieved, which implements an increase of the plasma current at ASDEX Upgrade. A higher plasma current and a high confinement lead to a raised density and for the ITER scenario to an electron density above the cutoff of the X2 mode at ASDEX Upgrade. Therefore, the X2 mode is reflected at the cutoff layer and cannot be used for central heating and the control of the tungsten concentration. One possibility to overcome this problem is to apply the third harmonic mode at reduced magnetic field. Here the cutoff is increased by 33% due to the dependence on the magnetic field. However, at the reachable plasma parameters at the reduced field the absorption of the X3 mode is incomplete (60-70 %) and the shine-trough power can destroy microwave sensitive components in ASDEX Upgrade. To solve this problem the magnetic field has to be optimized. A slightly increased magnetic field from 1.7 T to 1.8 T moves the second harmonic resonance in the region of confined plasma with high temperatures and density, so that this resonance can act as beam dump. The deposition in the plasma core is still central enough for the tungsten control ability of the ECRH. The benefit of the beam dump was verified in experiments with two different magnetic fields (1.7 T and 1.8 T). In case of the higher magnetic field, the stray radiation was reduced; simultaneously the electron temperature was increased. In addition

  5. Decreasing of energy consumption for space heating in existing residential buildings

    International Nuclear Information System (INIS)

    Stamov, S.; Zlateva, M.; Gechkov, N.

    2000-01-01

    An analysis is for the technical possibilities for reducing the energy consumption in existing buildings by means of the heat control and measurement. The basic performances of the heat capacity control methods, of the hierarchy structure of the control and of the heat measurement technologies are presented. This paper also presents the results from the long-term investigation of energy consumption for heating. The results area consist of three typical and uniform buildings in the city of Kazanlak (Bulgaria). The outcome of the investigation provides a valuable basis for future decisions to be made concerning reconstruction of heating installations and enables the results to be transferred. (Authors)

  6. Dry heat tolerance of the dry colony in Nostoc sp. HK-01 for useful usage in space agriculture

    Science.gov (United States)

    Kimura, Shunta; Tomita-Yokotani, Kaori; Yamashita, Masamichi; Sato, Seigo; Katoh, Hiroshi

    Space agriculture producing foods is important as one of approach for space habitation. Nostoc sp. HK-01 is one of terrestrial cyanobacterium having a high dry tolerance and it has several ability, photosynthesis, nitrogen fixation and usefulness as a food, it is thought that it can be used for space agriculture. Besides, a study on each tolerance predicted at the time of introduction to space agriculture is necessary. Therefore, as one of the tolerance that are intended to space environment, dry heat ( 100(°) C, 10 h ) tolerance of dry colony in Nostoc sp. HK-01 has been investigated, but the detail function of them has not yet been elucidated. We focused on the extracellular polysaccharides ( EPS ) having the various tolerance, desiccation, low temperature, NaCl, and heavy particle beam. We will consider the function and useful usage of this cyanobacterum in space agriculture after the consideration of the results of contribution of the possibility that EPS improves dry heat tolerance under a dry condition.

  7. Sun as an inexhaustible source of energy. Applications for space heating - cooling and air conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Zink, H [Solarheiztechnik G.m.b.H. und Co. K.G., Unterensingen (Germany, F.R.)

    1977-09-01

    Possible focal points for the utilization of solar energy in the field of domestic buildings and in the communal sector with hot water preparation for sport centres, swimming baths, hospitals, industry, and service are discussed. A diagram of a hot water preparation plant with solar collectors and stores is included, and preconditions for cooling with solar energy are discussed.

  8. Domestic connectivity: media, gender and the domestic sphere in Kenya

    DEFF Research Database (Denmark)

    Gustafsson, Jessica

    2017-01-01

    This article explores how increased media access influences Kenyan women’s everyday life and alters the domestic space. The study, which is set in Uasin Gishu County, Kenya, is based on 30 in-depth interviews with women. The article demonstrates that women have incorporated newly attained media i...... their traditional gender roles.......This article explores how increased media access influences Kenyan women’s everyday life and alters the domestic space. The study, which is set in Uasin Gishu County, Kenya, is based on 30 in-depth interviews with women. The article demonstrates that women have incorporated newly attained media...... into their daily lives and routines and that increased media access has opened up the home, turned the domestic space from a secluded place to a connected space, where women can get input from, connect and interact with the world beyond their immediate surrounding, while remaining at home concurrently fulfilling...

  9. Feasibility of using the water from the abandoned and flooded coal mines as an energy resource for space heating

    OpenAIRE

    Athresh, AP

    2017-01-01

    This research project aims to study the feasibility of using the water from the abandoned and flooded coal mines for space heating applications using a Ground Source Heat Pump (GSHP) in open loop configuration and take a conceptual idea to a commercial deployment level. The flooded coal mines are the legacy that has been left behind after the three centuries of continuous operations by the coal mining industry. The closure of all coal mines in the UK has led to the flooding of all those aband...

  10. Subcooled flow boiling heat transfer of ethanol aqueous solutions in vertical annulus space

    Directory of Open Access Journals (Sweden)

    Sarafraz M.M.

    2012-01-01

    Full Text Available The subcooled flow boiling heat-transfer characteristics of water and ethanol solutions in a vertical annulus have been investigated up to heat flux 132kW/m2. The variations in the effects of heat flux and fluid velocity, and concentration of ethanol on the observed heat-transfer coefficients over a range of ethanol concentrations implied an enhanced contribution of nucleate boiling heat transfer in flow boiling, where both forced convection and nucleate boiling heat transfer occurred. Increasing the ethanol concentration led to a significant deterioration in the observed heat-transfer coefficient because of a mixture effect, that resulted in a local rise in the saturation temperature of ethanol/water solution at the vapor-liquid interface. The reduction in the heat-transfer coefficient with increasing ethanol concentration is also attributed to changes in the fluid properties (for example, viscosity and heat capacity of tested solutions with different ethanol content. The experimental data were compared with some well-established existing correlations. Results of comparisons indicate existing correlations are unable to obtain the acceptable values. Therefore a modified correlation based on Gnielinski correlation has been proposed that predicts the heat transfer coefficient for ethanol/water solution with uncertainty about 8% that is the least in comparison to other well-known existing correlations.

  11. Calculation codes for radiant heat transfers; Les codes de calcul de rayonnement thermique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    This document reports on 12 papers about computerized simulation and modeling of radiant heat transfers and fluid flows in various industrial and domestic situations: space heating, metal industry (furnaces, boilers..), aerospace industry (turbojet engines, combustion chambers) etc.. This workshop was organized by the ``radiation`` section of the French society of thermal engineers. (J.S.)

  12. Calculation codes for radiant heat transfers; Les codes de calcul de rayonnement thermique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    This document reports on 12 papers about computerized simulation and modeling of radiant heat transfers and fluid flows in various industrial and domestic situations: space heating, metal industry (furnaces, boilers..), aerospace industry (turbojet engines, combustion chambers) etc.. This workshop was organized by the ``radiation`` section of the French society of thermal engineers. (J.S.)

  13. An evaluation of solar energy for heating a highway maintenance headquarters building.

    Science.gov (United States)

    1985-01-01

    A highway maintenance area headquarters building having overall dimensions of 64 ft - 8 in by 42 ft - 0 in was equipped with an active solar heating system to assist in heating space and domestic hot water. The solar system was instrumented and its o...

  14. The mechanical design of a vapor compressor for a heat pump to be used in space

    Science.gov (United States)

    Berner, F.; Oesch, H.; Goetz, K.; Savage, C. J.

    1982-01-01

    A heat pump developed for use in Spacelab as a stand-alone refrigeration unit as well as within a fluid loop system is discussed. It will provide an active thermal control for payloads. Specifications for the heat pump were established: (1) heat removal rates at the source; (2) heat source temperatures from room temperature; (3) heat-sink fluid temperatures at condenser inlet; and (4) minimum power consumption. A reversed Carnot cycle heat pump using Freon 12 as working fluid incorporating a one-cylinder reciprocating compressor was selected. The maximum crankshaft speed was fixed relatively high at 100 rpm. The specified cooling rates then made it necessary to select a cylinder volume of 10 cu cm, which was obtained with a bore of 40 mm and a stroke of 8 mm.

  15. Characterization of dynamic thermal control schemes and heat transfer pathways for incorporating variable emissivity electrochromic materials into a space suit heat rejection system

    Science.gov (United States)

    Massina, Christopher James

    The feasibility of conducting long duration human spaceflight missions is largely dependent on the provision of consumables such as oxygen, water, and food. In addition to meeting crew metabolic needs, water sublimation has long served as the primary heat rejection mechanism in space suits during extravehicular activity (EVA). During a single eight hour EVA, approximately 3.6 kg (8 lbm) of water is lost from the current suit. Reducing the amount of expended water during EVA is a long standing goal of space suit life support systems designers; but to date, no alternate thermal control mechanism has demonstrated the ability to completely eliminate the loss. One proposed concept is to convert the majority of a space suit's surface area into a radiator such that the local environment can be used as a radiative thermal sink for rejecting heat without mass loss. Due to natural variations in both internal (metabolic) loads and external (environmental) sink temperatures, radiative transport must be actively modulated in order to maintain an acceptable thermal balance. Here, variable emissivity electrochromic devices are examined as the primary mechanism for enabling variable heat rejection. This dissertation focuses on theoretical and empirical evaluations performed to determine the feasibility of using a full suit, variable emissivity radiator architecture for space suit thermal control. Operational envelopes are described that show where a given environment and/or metabolic load combination may or may not be supported by the evaluated thermal architecture. Key integration considerations and guidelines include determining allowable thermal environments, defining skin-to-radiator heat transfer properties, and evaluating required electrochromic performance properties. Analysis also considered the impacts of dynamic environmental changes and the architecture's extensibility to EVA on the Martian surface. At the conclusion of this work, the full suit, variable emissivity

  16. Performance investigations of liquid-metal heat pipes for space and terrestrial applications

    International Nuclear Information System (INIS)

    Kemme, J.E.; Keddy, E.S.; Phillips, J.R.

    1978-01-01

    The high heat transfer capacity of liquid-metal heat pipes is demonstrated in performance tests with mercury, potassium, sodium, and lithium working fluids and wick structures which serve to minimize liquid pressure losses and vapor/liquid interactions. Appropriate wicks for horizontal and vertical operation are described. It is shown that heat-transfer with these wicks is limited by vapor flow effects. Examples are given of particular effects associated with a long adiabatic section between evaporator and condenser and with a heat source of uniform temperature as opposed to a source of uniform power

  17. Special compressor technology for a new generation of heat pumps for domestic applications. Free piston technology with zero-oil torsion drive; Speciale compressortechnologie voor een nieuwe generatie warmtepompen voor huishoudelijke toepassingen. Vrijezuigertechnologie met olieloze torsie-aandrijving

    Energy Technology Data Exchange (ETDEWEB)

    Wissink, E.B. [TNO, Apeldoorn (Netherlands)

    2013-02-15

    To meet the increasing demand for small high efficient domestic heat pumps with a good total cost of ownership performance, a next generation of heat pumps is required. This article is dealing with the development of a new compressor technology for domestic heat pumps. After identification of the main losses in mechanical driven low capacity heat pump cycles, it became clear that a concept with a (semi-)free piston compressor has the potency to improve the efficiency significantly. An evaluation showed that none of the existing free-piston designs meets essential requirements like low internal friction, small size integrated electromotor and hermetic design suitable for all refrigerants, including ammonia. Therefore TNO designed a complete new free piston compressor making use of the following two design philosophies: balancing mechanical forces by using symmetry and reducing motor size by use of transmission ratio based on elastic deformation and the peak shaving effect of the energy contents (kinetic and elastic) of the compressor running in a natural frequency mode. This paper describes the background, the design steps and the final design of the new torsion compressor technology [Dutch] Om aan de toenemende vraag naar kleine hoog-efficiente warmtepompen voor woningverwarming met een lage exploitatiekostprijs te voldoen, is een nieuwe generatie warmtepompen vereist. Dit artikel beschrijft de ontwikkeling van een nieuwe compressortechnologie voor huishoudelijke warmtepompen. Na het onderzoeken van de belangrijkste verliezen in mechanisch aangedreven warmtepompsystemen met een klein verwarmingsvermogen werd duidelijk dat een concept met een (semi-)vrijezuigercompressor de potentie heeft om de efficientie aanzienlijk te verbeteren.

  18. Heat Exchanger/Humidifier Trade Study and Conceptual Design for the Constellation Space Suit Portable Life Support System Ventilation Subsystem

    Science.gov (United States)

    Paul, Heather L.; Sompayrac, Robert; Conger, Bruce; Chamberlain, Mateo

    2009-01-01

    As development of the Constellation Space Suit Element progresses, designing the most effective and efficient life support systems is critical. The baseline schematic analysis for the Portable Life Support System (PLSS) indicates that the ventilation loop will need some method of heat exchange and humidification prior to entering the helmet. A trade study was initiated to identify the challenges associated with conditioning the spacesuit breathing gas stream for temperature and water vapor control, to survey technological literature and resources on heat exchanger and humidifiers to provide solutions to the problems of conditioning the spacesuit breathing gas stream, and to propose potential candidate technologies to perform the heat exchanger and humidifier functions. This paper summarizes the results of this trade study and also describes the conceptual designs that NASA developed to address these issues.

  19. Simulation of the impact of financial incentives on solar energy utilization for space conditioning and water heating: 1985

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, H C

    1979-01-01

    Financial incentives designed to accelerate the use of solar energy for heating, cooling, and water heating of buildings have been proposed by both state and federal legislative bodies in the U.S.A. Among the most frequently mentioned incentives are sales and property tax exemptions, tax deductions and credits, rapid amortization provisions, and interest rate subsidies. At the present time there is little available information regarding the ability of such incentives to advance the rate of solar energy utilization. This paper describes the derivation and use of a computer simulation model designed to estimate solar energy use for space conditioning and water heating for given economic, climatic, and technological conditions. When applied to data from the Denver, Colorado metropolitan area, the simulation model predicts that sales tax exemptions would have little impact over the next decade, interest rate subsidies could more than double solar energy use, and the other proposed incentives would have an intermediate impact.

  20. Evaluation of Technical and Utility Programmatic Challenges With Residential Forced-Air Integrated Space/Water Heat Systems

    Energy Technology Data Exchange (ETDEWEB)

    Kingston, Tim [Partnership for Advanced Residential Retrofit, Des Plaines, IL (United States); Vadnal, Hillary [Partnership for Advanced Residential Retrofit, Des Plaines, IL (United States); Scott, Shawn [Partnership for Advanced Residential Retrofit, Des Plaines, IL (United States); Kalensky, Dave [Partnership for Advanced Residential Retrofit, Des Plaines, IL (United States)

    2016-12-01

    This multi-unit field demonstration of combined space and water heating (combi) systems was conducted to help document combi system installation and performance issues that needed to be addressed through research. The objective of the project was to put commercialized forced-air tankless combi units into the field through local contractors that were trained by manufacturers and GTI staff under the auspices of utility-implemented ETPs.

  1. Phase-space resolved measurement of 2nd harmonic ion cyclotron heating using FIDA tomography at the ASDEX Upgrade tokamak

    DEFF Research Database (Denmark)

    Weiland, M.; Bilato, R.; Geiger, B.

    2017-01-01

    Recent upgrades to the FIDA (fast-ion D-alpha) diagnostic at ASDEX Upgrade allow to reconstruct the fast-ion phase space at several radial positions with decent energy and pitch resolution. These new diagnostic capabilities are applied to study the physics of 2nd harmonic ion cyclotron heating, w....... Furthermore, comparisons to other fast-ion diagnostics (neutron yield and neutral particle analyzers) are discussed....

  2. Rational energy use and the gas utility. An economic analysis of energy efficiency strategies on the space heating market

    International Nuclear Information System (INIS)

    Helle, C.

    1994-01-01

    Apart from the political authorities, also the supply utilities may contribute to a more widespread rational energy use. This investigtion focuses on the gas utilities, which have a wide range of options for higher energy efficiency, especially on the space heating market. These options are analyzed in the framework of the process of company straategy planning. Particular interest is taken in the product-political strategy of forward integration. (orig.) [de

  3. Adaptive neuro-fuzzy based inferential sensor model for estimating the average air temperature in space heating systems

    Energy Technology Data Exchange (ETDEWEB)

    Jassar, S.; Zhao, L. [Department of Electrical and Computer Engineering, Ryerson University, 350 Victoria Street, Toronto, ON (Canada); Liao, Z. [Department of Architectural Science, Ryerson University (Canada)

    2009-08-15

    The heating systems are conventionally controlled by open-loop control systems because of the absence of practical methods for estimating average air temperature in the built environment. An inferential sensor model, based on adaptive neuro-fuzzy inference system modeling, for estimating the average air temperature in multi-zone space heating systems is developed. This modeling technique has the advantage of expert knowledge of fuzzy inference systems (FISs) and learning capability of artificial neural networks (ANNs). A hybrid learning algorithm, which combines the least-square method and the back-propagation algorithm, is used to identify the parameters of the network. This paper describes an adaptive network based inferential sensor that can be used to design closed-loop control for space heating systems. The research aims to improve the overall performance of heating systems, in terms of energy efficiency and thermal comfort. The average air temperature results estimated by using the developed model are strongly in agreement with the experimental results. (author)

  4. Natural convective flows in a horizontal channel provided with heating isothermal blocks: Effect of the inter blocks spacing

    International Nuclear Information System (INIS)

    Bakkas, M.; Hasnaoui, M.; Amahmid, A.

    2010-01-01

    A numerical study of laminar steady natural convection induced in a two dimensional horizontal channel provided with rectangular heating blocks, periodically mounted on its lower wall, is carried out. The blocks' surface temperature, T H ' , is maintained constant and the former are connected with adiabatic surfaces. The upper wall of the channel is maintained cold at a temperature T C ' H ' . Fluid flow, temperature fields and heat transfer rates are presented for different combinations of the governing parameters which are the Rayleigh number (10 2 ≤Ra≤2x10 6 ), the blocks' spacing (1/4≤C=l ' /H ' ≤1), the blocks' height (1/8≤B=h ' /H ' ≤1/2) and the relative width of the blocks (A=(L ' -l ' )/H ' =1/2). The results obtained in the case of air (Pr = 0.72) show that the flow structure and the heat transfer are significantly influenced by the control parameters. It is found that there are situations where the increase of the blocks' spacing leads to a reduction of heat transfer.

  5. Effects of Heating on Teflon(Registered Trademark) FEP Thermal Control Material from the Hubble Space Telescope

    Science.gov (United States)

    deGroh, Kim; Gaier, James R.; Hall, Rachelle L.; Norris, Mary Jo; Espe, Matthew P.; Cato, Daveen R.

    1999-01-01

    Metallized Teflon(Registered Trademark) FEP (fluorinated ethylene propylene) thermal control material on the Hubble Space Telescope (HST) is degrading in the space environment. Teflon(Registered Trademark) FEP thermal control blankets (space-facing FEP) retrieved during the first servicing mission (SM1) were found to be embrittled on solar facing surfaces and contained microscopic cracks. During the second servicing mission (SM2) astronauts noticed that the FEP outer layer of the multi-layer insulation (MLI) covering the telescope was cracked in many locations around the telescope. Large cracks were observed on the light shield, forward shell and equipment bays. A tightly curled piece of cracked FEP from the light shield was retrieved during SM2 and was severely embrittled, as witnessed by ground testing. A Failure Review Board (FRB) was organized to determine the mechanism causing the MLI degradation. Density, x-ray crystallinity and solid state nuclear magnetic resonance (NMR) analyses of FEP retrieved during SM1 were inconsistent with results of FEP retrieved during SM2. Because the retrieved SM2 material curled while in space, it experienced a higher temperature extreme during thermal cycling, estimated at 200 C, than the SM1 material, estimated at 50 C. An investigation on the effects of heating pristine and FEP exposed on HST was therefore conducted. Samples of pristine. SM1, and SM2 FEP were heated to 200 C and evaluated for changes in density and morphology. Elevated temperature exposure was found to have a major impact on the density of the retrieved materials. Characterization of polymer morphology of as-received and heated FEP samples by NMR provided results that were consistent with the density results. These findings have provided insight to the damage mechanisms of FEP in the space environment.

  6. Heat planning for fossil-fuel-free district heating areas with extensive end-use heat savings

    DEFF Research Database (Denmark)

    Harrestrup, Maria; Svendsen, S.

    2014-01-01

    is a theoretical investigation of the district heating system in the Copenhagen area, in which heat conservation is related to the heat supply in buildings from an economic perspective. Supplying the existing building stock from low-temperature energy resources, e.g. geothermal heat, might lead to oversized......The Danish government plans to make the Danish energy system to be completely free of fossil fuels by 2050 and that by 2035 the energy supply for buildings and electricity should be entirely based on renewable energy sources. To become independent from fossil fuels, it is necessary to reduce...... the energy consumption of the existing building stock, increase energy efficiency, and convert the present heat supply from fossil fuels to renewable energy sources. District heating is a sustainable way of providing space heating and domestic hot water to buildings in densely populated areas. This paper...

  7. Domestic energy fact file

    Energy Technology Data Exchange (ETDEWEB)

    Shorrock, L D; Henderson, G [Building Research Establishment, Watford (United Kingdom); Bown, J H.F. [NBA Tectonics, London (United Kingdom)

    1992-01-01

    The purpose of this publication to gather together in one volume some of the more important United Kingdom data on domestic energy and the measures that have been taken to improve the efficiency with which it is used. The introductory section discusses the main underlying trends affecting domestic energy use. It is followed by six main sections: Section 1 deals with fuel prices and household expenditure on energy. Section 2 is concerned with basic statistics on population, households and the housing stock (age, tenure, dwelling type and regional distribution). Section 3 presents information on the uptake of insulation measures in the housing stock. Section 4 presents information on changes to the housing stock heat loss, heating systems, temperatures and energy use. This section looks at what would have happened to the energy use of the housing stock if energy efficiency improvements had not been introduced. Section 4 contains the main conclusions on the effectiveness of insulation, improvements in efficiency and the rising standards of service achieved within the housing stock. Section 5 draws together the topics discussed in section 4 to illustrate the individual effects of rising levels of service, external temperature variations, improved insulation and improved heating efficiency, and how these combine to determine domestic section energy consumption. Section 6 considers the fuels used to meet the energy demand of the housing stock and the carbon dioxide emissions which result from this fuel use. The primary energy consumption associated with the energy delivered to the housing stock is also addressed in this section. A final energy balance diagram draws together the various topics discussed in the report by showing the main energy flows related to the housing stock. (author)

  8. In-Space technology experiments program. A high efficiency thermal interface (using condensation heat transfer) between a 2-phase fluid loop and heatpipe radiator: Experiment definition phase

    Science.gov (United States)

    Pohner, John A.; Dempsey, Brian P.; Herold, Leroy M.

    1990-01-01

    Space Station elements and advanced military spacecraft will require rejection of tens of kilowatts of waste heat. Large space radiators and two-phase heat transport loops will be required. To minimize radiator size and weight, it is critical to minimize the temperature drop between the heat source and sink. Under an Air Force contract, a unique, high-performance heat exchanger is developed for coupling the radiator to the transport loop. Since fluid flow through the heat exchanger is driven by capillary forces which are easily dominated by gravity forces in ground testing, it is necessary to perform microgravity thermal testing to verify the design. This contract consists of an experiment definition phase leading to a preliminary design and cost estimate for a shuttle-based flight experiment of this heat exchanger design. This program will utilize modified hardware from a ground test program for the heat exchanger.

  9. Industrial space heating and cooling from stored spent nuclear power plant fuel

    International Nuclear Information System (INIS)

    Shaver, B.O.; Doman, J.W.

    1980-01-01

    Projections by the Department of Energy indicate that some 5800 metric tons of spent fuel from nuclear power reactors are now in storage and that some 33000 metric tons are expected to be in storage in 1990. The bulk of the spent fuel is currently stored in water-filled basins at the reactor sites from which the material was discharged. The thermal energy in the fuel is dissipated to atmospheres via a pumped water-to-air heat exchanger system. This paper describes a feasibility study of potential methods for the use of the heat. Also, potential applications of heat recovery systems at larger AFR storage facilities were investigated

  10. Domestic Violence

    Science.gov (United States)

    ... tell if my partner is abusive? Disagreements and arguments, even heated ones, are part of a normal ... patient, resources, and limitations unique to institution or type of practice, may be appropriate. Copyright August 2017 ...

  11. Domestic cat

    Science.gov (United States)

    Diffendorfer, James E.

    2017-01-01

    The familiar domestic cat is not native to southern California and is considered an invasive spe-cies by biologists and conservation organizations. When owners abandon their cats, wild or feral populations may arise, as they have in San Diego County. Cats’ pelage color, tail length, and hair thickness vary widely, given human fascination with breeding diverse phenotypes, but all have a typical felid body with upright ears, forward-looking eyes adapted for nocturnal foraging, protractible claws, and a sinuous, flexible body. Cats allowed outdoors and feral cats kill and eat a wide variety of vertebrates such as small mammals, birds, and reptiles

  12. Solar space heating for the Visitors Center, Stephens College, Columbia, Missouri

    Science.gov (United States)

    1980-01-01

    The solar energy system located at the Visitors' Center on the Stephens College Campus, Columbia, Missouri is discussed. The system is installed in a four-story, 15,000 square foot building. The solar energy system is an integral design of the building and utilizes 176 hydronic flat plate collectors which use a 50 percent water ethylene blycol solution and water-to-water heat exchanger. Solar heated water is stored in a 5,000 gallon water storage tank located in the basement equipment room. A natural gas fired hot water boiler supplies hot water when the solar energy heat supply fails to meet the demand. The designed solar contribution is 71 percent of the heating load.

  13. Synergies of wind power and electrified space heating: case study for Beijing.

    Science.gov (United States)

    Chen, Xinyu; Lu, Xi; McElroy, Michael B; Nielsen, Chris P; Kang, Chongqing

    2014-01-01

    Demands for electricity and energy to supply heat are expected to expand by 71% and 47%, respectively, for Beijing in 2020 relative to 2009. If the additional electricity and heat are supplied solely by coal as is the current situation, annual emissions of CO2 may be expected to increase by 59.6% or 99 million tons over this interval. Assessed against this business as usual (BAU) background, the present study indicates that significant reductions in emissions could be realized using wind-generated electricity to provide a source of heat, employed either with heat pumps or with electric thermal storage (ETS) devices. Relative to BAU, reductions in CO2 with heat pumps assuming 20% wind penetration could be as large as 48.5% and could be obtained at a cost for abatement of as little as $15.6 per ton of avoided CO2. Even greater reductions, 64.5%, could be realized at a wind penetration level of 40% but at a higher cost, $29.4 per ton. Costs for reduction of CO2 using ETS systems are significantly higher, reflecting the relatively low efficiency for conversion of coal to power to heat.

  14. The space heating market and the big customers; Vaermemarknaden och storkunderna

    Energy Technology Data Exchange (ETDEWEB)

    Maardsjoe, Olle

    2007-07-01

    This report focuses on the cost of heating in multiple-occupancy buildings, commercial premises and industrial premises. A summary has been created of the development of heating, primarily in the 2000s, for as long as statistics are available (essentially 2004). Total heating has seen a reduction over the period as regards both total usage and specifically in kWh/sq. m. District heating, on the other hand, has seen an increase in total turnover, now accounting for around two-thirds of demand - or about 42 TWh - as well. The increase in district heating has come about partly as a result of property renovation and people exchanging their sources of heating. A reduction in oil consumption has been the primary cause of this transition. There has also been a slight increase in the number of heat pumps in use. In total, heat pumps account for a small proportion of the heating of the properties in question. Heating costs account for a large proportion of operating expenses for property owners, in fact up to 40-50 percent of ongoing operating expenses. Reducing the cost of heating is very important, as this directly affects the property owners' bottom lines. Contractors are offering services to help property owners to optimise their energy-saving measures. The price of district heating, where this is available, is being used as a basis. This is why the structure of the price of district heating affects what measures are implemented. In price constructions with too high a flexible element, there is plenty of incentive to make savings on energy. District heating suppliers' coverage of set costs is reduced once the measures to ensure savings have been implemented, and so they have to increase their prices retrospectively. In price constructions with a high set element, there is little incentive to make savings, with a subsequent increase in demand for heating in extreme cases. District heating suppliers can be forced to make investments in both generation and

  15. Data gathering in support of phase O program for waste heat utilization from nuclear enrichment facilities, Ohio

    International Nuclear Information System (INIS)

    1978-01-01

    The gathering of demographic, community development, and economic data for the region impacted by the Pikeville (Ohio) Nuclear Enrichment Facility is described. These data are to be used for establishing possible community uses, e.g., space heating, domestic water heating, and industrial uses, of waste heat from the facility. It was concluded that although the economic feasibility of such waste heat utilization remains to be proven, the community would cooperate in a feasibility demonstration program

  16. Heat transfer on HLM cooled wire-spaced fuel pin bundle simulator in the NACIE-UP facility

    Energy Technology Data Exchange (ETDEWEB)

    Di Piazza, Ivan, E-mail: ivan.dipiazza@enea.it [Italian National Agency for New Technologies, Energy and Sustainable Economic Development, C.R. ENEA Brasimone, Camugnano (Italy); Angelucci, Morena; Marinari, Ranieri [University of Pisa, Dipartimento di Ingegneria Civile e Industriale, Pisa (Italy); Tarantino, Mariano [Italian National Agency for New Technologies, Energy and Sustainable Economic Development, C.R. ENEA Brasimone, Camugnano (Italy); Forgione, Nicola [University of Pisa, Dipartimento di Ingegneria Civile e Industriale, Pisa (Italy)

    2016-04-15

    Highlights: • Experiments with a wire-wrapped 19-pin fuel bundle cooled by LBE. • Wall and bulk temperature measurements at three axial positions. • Heat transfer and error analysis in the range of low mass flow rates and Péclet number. • Comparison of local and section-averaged Nusselt number with correlations. - Abstract: The NACIE-UP experimental facility at the ENEA Brasimone Research Centre (Italy) allowed to evaluate the heat transfer coefficient of a wire-spaced fuel bundle cooled by lead-bismuth eutectic (LBE). Lead or lead-bismuth eutectic are very attractive as coolants for the GEN-IV fast reactors due to the good thermo-physical properties and the capability to fulfil the GEN-IV goals. Nevertheless, few experimental data on heat transfer with heavy liquid metals (HLM) are available in literature. Furthermore, just a few data can be identified on the specific topic of wire-spaced fuel bundle cooled by HLM. Additional analysis on thermo-fluid dynamic behaviour of the HLM inside the subchannels of a rod bundle is necessary to support the design and safety assessment of GEN. IV/ADS reactors. In this context, a wire-spaced 19-pin fuel bundle was installed inside the NACIE-UP facility. The pin bundle is equipped with 67 thermocouples to monitor temperatures and analyse the heat transfer behaviour in different sub-channels and axial positions. The experimental campaign was part of the SEARCH FP7 EU project to support the development of the MYRRHA irradiation facility (SCK-CEN). Natural and mixed circulation flow regimes were investigated, with subchannel Reynolds number in the range Re = 1000–10,000 and heat flux in the range q″ = 50–500 kW/m{sup 2}. Local Nusselt numbers were calculated for five sub-channels in different ranks at three axial positions. Section-averaged Nusselt number was also defined and calculated. Local Nusselt data showed good consistency with some of the correlation existing in literature for heat transfer in liquid metals

  17. Heat transfer on HLM cooled wire-spaced fuel pin bundle simulator in the NACIE-UP facility

    International Nuclear Information System (INIS)

    Di Piazza, Ivan; Angelucci, Morena; Marinari, Ranieri; Tarantino, Mariano; Forgione, Nicola

    2016-01-01

    Highlights: • Experiments with a wire-wrapped 19-pin fuel bundle cooled by LBE. • Wall and bulk temperature measurements at three axial positions. • Heat transfer and error analysis in the range of low mass flow rates and Péclet number. • Comparison of local and section-averaged Nusselt number with correlations. - Abstract: The NACIE-UP experimental facility at the ENEA Brasimone Research Centre (Italy) allowed to evaluate the heat transfer coefficient of a wire-spaced fuel bundle cooled by lead-bismuth eutectic (LBE). Lead or lead-bismuth eutectic are very attractive as coolants for the GEN-IV fast reactors due to the good thermo-physical properties and the capability to fulfil the GEN-IV goals. Nevertheless, few experimental data on heat transfer with heavy liquid metals (HLM) are available in literature. Furthermore, just a few data can be identified on the specific topic of wire-spaced fuel bundle cooled by HLM. Additional analysis on thermo-fluid dynamic behaviour of the HLM inside the subchannels of a rod bundle is necessary to support the design and safety assessment of GEN. IV/ADS reactors. In this context, a wire-spaced 19-pin fuel bundle was installed inside the NACIE-UP facility. The pin bundle is equipped with 67 thermocouples to monitor temperatures and analyse the heat transfer behaviour in different sub-channels and axial positions. The experimental campaign was part of the SEARCH FP7 EU project to support the development of the MYRRHA irradiation facility (SCK-CEN). Natural and mixed circulation flow regimes were investigated, with subchannel Reynolds number in the range Re = 1000–10,000 and heat flux in the range q″ = 50–500 kW/m"2. Local Nusselt numbers were calculated for five sub-channels in different ranks at three axial positions. Section-averaged Nusselt number was also defined and calculated. Local Nusselt data showed good consistency with some of the correlation existing in literature for heat transfer in liquid metals for

  18. Investigation of the thermal resistance of timber attic spaces with reflective foil and bulk insulation, heat flow up

    Energy Technology Data Exchange (ETDEWEB)

    Belusko, M.; Bruno, F.; Saman, W. [Institute for Sustainable Systems and Technologies, University of South Australia, Mawson Lakes Boulevard, SA 5095 (Australia)

    2011-01-15

    An experimental investigation was undertaken in which the thermal resistance for the heat flow through a typical timber framed pitched roofing system was measured under outdoor conditions for heat flow up. The measured thermal resistance of low resistance systems such as an uninsulated attic space and a reflective attic space compared well with published data. However, with higher thermal resistance systems containing bulk insulation within the timber frame, the measured result for a typical installation was as low as 50% of the thermal resistance determined considering two dimensional thermal bridging using the parallel path method. This result was attributed to three dimensional heat flow and insulation installation defects, resulting from the design and construction method used. Translating these results to a typical house with a 200 m{sup 2} floor area, the overall thermal resistance of the roof was at least 23% lower than the overall calculated thermal resistance including two dimensional thermal bridging. When a continuous layer of bulk insulation was applied to the roofing system, the measured values were in agreement with calculated resistances representing a more reliable solution. (author)

  19. A techno-economic comparison of ground-coupled and air-coupled heat pump system for space cooling

    Energy Technology Data Exchange (ETDEWEB)

    Esen, Hikmet; Esen, Mehmet [Department of Mechanical Education, Faculty of Technical Education, University of Firat, 23119 Elazig (Turkey); Inalli, Mustafa [Department of Mechanical Engineering, Faculty of Engineering, University of Firat, 23119 Elazig (Turkey)

    2007-05-15

    This paper reports a techno-economic comparison between a ground-coupled heat pump (GCHP) system and an air-coupled heat pump (ACHP) system. The systems connected to a test room in Firat University, Elazig (38.41{sup o}N, 39.14{sup o}E), Turkey, were designed and constructed for space cooling. The performances of the GCHP and the ACHP system were experimentally determined. The experimental results were obtained from June to September in cooling season of 2004. The average cooling performance coefficients (COP{sub sys}) of the GCHP system for horizontal ground heat exchanger (HGHE) in the different trenches, at 1 and 2m depths, were obtained to be 3.85 and 4.26, respectively and the COP{sub sys} of the ACHP system was determined to be 3.17. The test results indicate that system parameters can have an important effect on performance, and that GCHP systems are economically preferable to ACHP systems for the purpose of space cooling. (author)

  20. Reducing residential solid fuel combustion through electrified space heating leads to substantial air quality, health and climate benefits in China's Beijing-Tianjin-Hebei region

    Science.gov (United States)

    Yang, J.; Mauzerall, D. L.

    2017-12-01

    During periods of high pollution in winter, household space heating can contribute more than half of PM2.5 concentrations in China's Beijing-Tianjin-Hebei (BTH) region. The majority of rural households and some urban households in the region still heat with small stoves and solid fuels such as raw coal, coal briquettes and biomass. Thus, reducing emissions from residential space heating has become a top priority of the Chinese government's air pollution mitigation plan. Electrified space heating is a promising alternative to solid fuel. However, there is little analysis of the air quality and climate implications of choosing various electrified heating devices and utilizing different electricity sources. Here we conduct an integrated assessment of the air quality, human health and climate implications of various electrified heating scenarios in the BTH region using the Weather Research and Forecasting model with Chemistry. We use the Multi-resolution Emission Inventory for China for the year 2012 as our base case and design two electrification scenarios in which either direct resistance heaters or air source heat pumps are installed to replace all household heating stoves. We initially assume all electrified heating devices use electricity from supercritical coal-fired power plants. We find that installing air source heat pumps reduces CO2 emissions and premature deaths due to PM2.5 pollution more than resistance heaters, relative to the base case. The increased health and climate benefits of heat pumps occur because they have a higher heat conversion efficiency and thus require less electricity for space heating than resistance heaters. We also find that with the same heat pump installation, a hybrid electricity source (40% of the electricity generated from renewable sources and the rest from coal) further reduces both CO2 emissions and premature deaths than using electricity only from coal. Our study demonstrates the air pollution and CO2 mitigation potential and

  1. Thermal-Flow Code for Modeling Gas Dynamics and Heat Transfer in Space Shuttle Solid Rocket Motor Joints

    Science.gov (United States)

    Wang, Qunzhen; Mathias, Edward C.; Heman, Joe R.; Smith, Cory W.

    2000-01-01

    A new, thermal-flow simulation code, called SFLOW. has been developed to model the gas dynamics, heat transfer, as well as O-ring and flow path erosion inside the space shuttle solid rocket motor joints by combining SINDA/Glo, a commercial thermal analyzer. and SHARPO, a general-purpose CFD code developed at Thiokol Propulsion. SHARP was modified so that friction, heat transfer, mass addition, as well as minor losses in one-dimensional flow can be taken into account. The pressure, temperature and velocity of the combustion gas in the leak paths are calculated in SHARP by solving the time-dependent Navier-Stokes equations while the heat conduction in the solid is modeled by SINDA/G. The two codes are coupled by the heat flux at the solid-gas interface. A few test cases are presented and the results from SFLOW agree very well with the exact solutions or experimental data. These cases include Fanno flow where friction is important, Rayleigh flow where heat transfer between gas and solid is important, flow with mass addition due to the erosion of the solid wall, a transient volume venting process, as well as some transient one-dimensional flows with analytical solutions. In addition, SFLOW is applied to model the RSRM nozzle joint 4 subscale hot-flow tests and the predicted pressures, temperatures (both gas and solid), and O-ring erosions agree well with the experimental data. It was also found that the heat transfer between gas and solid has a major effect on the pressures and temperatures of the fill bottles in the RSRM nozzle joint 4 configuration No. 8 test.

  2. Residential space heating with wood burning stoves. Energy efficiency and indoor climate; Boligopvarmning ved braendefyring. Energieffektivitet og indeklima

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Ole Michael; Afshari, A.; Bergsoee, N.C.; Carvalho, R. [Miljoestyrelsen, Copenhagen (Denmark); Aalborg Univ.. Statens Byggeforskningsinstitut, Aalborg (Denmark))

    2012-11-01

    Two issues turn up concerning how to use wood-burning stoves in modern homes. The first is whether wood-burning stoves in future may still act as a genuine heat source, given that new and refurbished single-family houses retain the heat much better than older ones and therefore need less and less energy for space heating. The second issue is whether it will still be possible to use wood-burning stoves in modern houses where the air exchange is controlled by mechanical ventilation or possibly heat recovery. It is a question whether firing techniques can be developed that will work in airtight houses with mechanical ventilation and negative pressure, so that harmful particle emissions can be avoided. To illustrate the first issue, a field study was designed to look carefully at seven modern wood-burning stoves that were set up in six new houses and one older house and investigated, both in terms of firing and heat release. As a background for this part of the study, a heat balance calculation was made for each house. The question is, whether wood-burning stoves will also in the future have a role to play as a heating source. Modern houses grow ever tighter and only need to be supplied with a small quantity of heat. The new Danish Buildings Requirement, 2010 has resulted in a further reduction of 25 % of the energy demand, including the energy supply for heating. However, the new requirements imply that the heating season eventually become so short that a traditional central heating installation becomes superfluous. This means that by using the small amounts of wood cut in gardens and hedgerows of the neighbourhood, a wood-burning stove will, in principle, cover the heating demand. Therefore, the question is rather whether a wood-burning stove is manufactured that can successfully be adapted to new houses. As a consequence of this development, future stoves must be further scaled down in order to meet the heating demand of a modern low-energy house and the stoves must

  3. Thermal energy storage with geothermal triplet for space heating and cooling

    Science.gov (United States)

    Bloemendal, Martin; Hartog, Niels

    2017-04-01

    Many governmental organizations and private companies have set high targets in avoiding CO2 emissions and reducing energy (Kamp, 2015; Ministry-of-Economic-affairs, 2016). ATES systems use groundwater wells to overcome the discrepancy in time between the availability of heat (during summer) and the demand for heat (during winter). Aquifer Thermal Energy Storage is an increasingly popular technique; currently over 2000 ATES systems are operational in the Netherlands (Graaf et al., 2016). High temperature ATES may help to improve performance of these conventional ATES systems. ATES systems use heat pumps to get the stored heat to the required temperature for heating of around 40-50°C and to produce the cold water for cooling in summer. These heat pumps need quite a lot of power to run; on average an ATES system produces 3-4 times less CO2 emission compared to conventional. Over 60% of those emission are accounted for by the heat pump (Dekker, 2016). This heat pump power consumption can be reduced by utilizing other sources of sustainable heat and cooling capacity for storage in the subsurface. At such operating temperatures the required storage temperatures do no longer match the return temperatures in the building systems. Therefore additional components and an additional well are required to increase the groundwater temperature in summer (e.g. solar collectors) and decrease it in winter (e.g. dry coolers). To prevent "pollution" of the warm and cold well return water from the building can be stored in a third well until weather conditions are suitable for producing the required storage temperature. Simulations and an economical evaluation show great potential for this type of aquifer thermal energy storage; economic performance is better than normal ATES while the emissions are reduce by a factor ten. At larger temperature differences, also the volume of groundwater required to pump around is much less, which causes an additional energy saving. Research now

  4. Theoretical Study of Heat Transfer through a Sun Space Filled with a Porous Medium

    Directory of Open Access Journals (Sweden)

    Ahmed Tawfeeq Ahmed Al-Sammarraie

    2016-10-01

    Full Text Available A theoretical study had been conducted to detect the effect of using a porous medium in sunspace to reduce  heating  load  and  overcoming  coldness  of  winter  in  the  cold  regions.  In  this  work,  the  heat transferred and stored in the storage wall was investigated. The mathematical model was unsteady, heat conduction equation with nonlinear boundary conditions was solved by using finite difference method and the solution technique  of heat conduction had based  on the  Crank Nicholson method. The results had adopted  on  the  aspect  ratio  (H/L=30,  Darcy  number  (Da=10-3,  porosity  (φ=0.35  and  particle  to  fluid thermal conductivity ratio (kp/kf=38.5. The results showed that using the porous medium had enhanced the heat transferred and stored in the storage wall. For   the outside storage wall temperature, an increase of 19.7%  was achieved by using the porous medium instead of the air, while it was 20.3%  for the inside storage wall temperature.

  5. Spatial Characteristics of Small Green Spaces' Mitigating Effects on Microscopic Urban Heat Islands

    Science.gov (United States)

    Park, J.; Lee, D. K.; Jeong, W.; Kim, J. H.; Huh, K. Y.

    2015-12-01

    The purpose of the study is to find small greens' disposition, types and sizes to reduce air temperature effectively in urban blocks. The research sites were six high developed blocks in Seoul, Korea. Air temperature was measured with mobile loggers in clear daytime during summer, from August to September, at screen level. Also the measurement repeated over three times a day during three days by walking and circulating around the experimental blocks and the control blocks at the same time. By analyzing spatial characteristics, the averaged air temperatures were classified with three spaces, sunny spaces, building-shaded spaces and small green spaces by using Kruskal-Wallis Test; and small green spaces in 6 blocks were classified into their outward forms, polygonal or linear and single or mixed. The polygonal and mixed types of small green spaces mitigated averaged air temperature of each block which they belonged with a simple linear regression model with adjusted R2 = 0.90**. As the area and volume of these types increased, the effect of air temperature reduction (ΔT; Air temperature difference between sunny space and green space in a block) also increased in a linear relationship. The experimental range of this research is 100m2 ~ 2,000m2 of area, and 1,000m3 ~ 10,000m3 of volume of small green space. As a result, more than 300m2 and 2,300m3 of polygonal green spaces with mixed vegetation is required to lower 1°C; 650m2 and 5,000m3 of them to lower 2°C; about 2,000m2 and about 10,000m3 of them to lower 4°C air temperature reduction in an urban block.

  6. Assessing the air quality impact of nitrogen oxides and benzene from road traffic and domestic heating and the associated cancer risk in an urban area of Verona (Italy)

    Science.gov (United States)

    Schiavon, Marco; Redivo, Martina; Antonacci, Gianluca; Rada, Elena Cristina; Ragazzi, Marco; Zardi, Dino; Giovannini, Lorenzo

    2015-11-01

    Simulations of emission and dispersion of nitrogen oxides (NOx) are performed in an urban area of Verona (Italy), characterized by street canyons and typical sources of urban pollutants. Two dominant source categories are considered: road traffic and, as an element of novelty, domestic heaters. Also, to assess the impact of urban air pollution on human health and, in particular, the cancer risk, simulations of emission and dispersion of benzene are carried out. Emissions from road traffic are estimated by the COPERT 4 algorithm, whilst NOx emission factors from domestic heaters are retrieved by means of criteria provided in the technical literature. Then maps of the annual mean concentrations of NOx and benzene are calculated using the AUSTAL2000 dispersion model, considering both scenarios representing the current situation, and scenarios simulating the introduction of environmental strategies for air pollution mitigation. The simulations highlight potentially critical situations of human exposure that may not be detected by the conventional network of air quality monitoring stations. The proposed methodology provides a support for air quality policies, such as planning targeted measurement campaigns, re-locating monitoring stations and adopting measures in favour of better air quality in urban planning. In particular, the estimation of the induced cancer risk is an important starting point to conduct zoning analyses and to detect the areas where population is more directly exposed to potential risks for health.

  7. Field measurement and estimate of gaseous and particle pollutant emissions from cooking and space heating processes in rural households, northern China

    Science.gov (United States)

    Chen, Yuanchen; Shen, Guofeng; Liu, Weijian; Du, Wei; Su, Shu; Duan, Yonghong; Lin, Nan; Zhuo, Shaojie; Wang, Xilong; Xing, Baoshan; Tao, Shu

    2016-01-01

    Pollutant emissions into outdoor air from cooking and space heating processes with various solid fuels were measured, and daily household emissions were estimated from the kitchen performance tests. The burning of honeycomb briquette had the lowest emission factors, while the use of wood produced the highest pollutants. Daily emissions from space heating were significantly higher than those from cooking, and the use of honeycomb briquette for cooking and raw coal chunk for space heating reduces 28%, 24% and 25% for CO, PM10 and PM2.5, compared to wood for cooking and peat for space heating. Much higher emissions were observed during the initial phase than the stable phase due to insufficient air supply and lower combustion temperature at the beginning of burning processes. However, more mass percent of fine particles formed in the later high temperature stable burning phase may increase potential inhalation exposure risks.

  8. Domestic violence

    Directory of Open Access Journals (Sweden)

    Kiurski Jasmina

    2003-01-01

    Full Text Available In this article author examines a definition of a family, the role of a family as a social and legal institution as well as state reaction in a situation of mal function of a family. Special attention is given to a definition of a family, its protective function and criminal law in modern legal systems. Author also analyzes recent reform of our legislation firstly new criminal offence (Article 118a of the Criminal Code of Republic of Serbia - Domestic Violence - and its relation to other similar criminal offences. Finally, author gives an overview of up-to-now practice from District and Municipal Prosecutors Offices in Belgrade and suggestions for solving observed problems in implementation of this criminal offence.

  9. Energy Efficiency and Sustainability Evaluation of Space and Water Heating in Urban Residential Buildings of the Hot Summer and Cold Winter Zone in China

    OpenAIRE

    Xiao Chen; Yongquan Wen; Nanyang Li

    2016-01-01

    With the urbanization process of the hot summer and cold winter (HSCW) zone in China, the energy consumption of space and water heating in urban residential buildings of the HSCW zone has increased rapidly. This study presents the energy efficiency and sustainability evaluation of various ways of space and water heating taking 10 typical cities in the HSCW zone as research cases. Two indicators, primary energy efficiency (PEE) and sustainability index based on exergy efficiency, are adopted t...

  10. Building America Case Study: Effect of Ducted HPWH on Space Conditioning and Water Heating Energy Use - Central Florida Lab Home, Cocoa, Florida

    Energy Technology Data Exchange (ETDEWEB)

    C. Colon, E. Martin, and D. Parker

    2017-04-01

    The purpose of this research is to investigate the impact of ducted heat pump water heaters (HPWH's) on space conditioning and water heating energy use in residential applications. Two identical HPWH's, each of 60 gallon capacity were tested side by side at the Flexible Residential Test facility (FRTF) laboratories of the Florida Solar Energy Center (FSEC) campus in Cocoa, Florida. The water heating experiments were run in each test house from July 2014 until February 2015.

  11. Pulse-echo ultrasonic inspection system for in-situ nondestructive inspection of Space Shuttle RCC heat shields.

    Energy Technology Data Exchange (ETDEWEB)

    Roach, Dennis Patrick; Walkington, Phillip D.; Rackow, Kirk A.

    2005-06-01

    The reinforced carbon-carbon (RCC) heat shield components on the Space Shuttle's wings must withstand harsh atmospheric reentry environments where the wing leading edge can reach temperatures of 3,000 F. Potential damage includes impact damage, micro cracks, oxidation in the silicon carbide-to-carbon-carbon layers, and interlaminar disbonds. Since accumulated damage in the thick, carbon-carbon and silicon-carbide layers of the heat shields can lead to catastrophic failure of the Shuttle's heat protection system, it was essential for NASA to institute an accurate health monitoring program. NASA's goal was to obtain turnkey inspection systems that could certify the integrity of the Shuttle heat shields prior to each mission. Because of the possibility of damaging the heat shields during removal, the NDI devices must be deployed without removing the leading edge panels from the wing. Recently, NASA selected a multi-method approach for inspecting the wing leading edge which includes eddy current, thermography, and ultrasonics. The complementary superposition of these three inspection techniques produces a rigorous Orbiter certification process that can reliably detect the array of flaws expected in the Shuttle's heat shields. Sandia Labs produced an in-situ ultrasonic inspection method while NASA Langley developed the eddy current and thermographic techniques. An extensive validation process, including blind inspections monitored by NASA officials, demonstrated the ability of these inspection systems to meet the accuracy, sensitivity, and reliability requirements. This report presents the ultrasonic NDI development process and the final hardware configuration. The work included the use of flight hardware and scrap heat shield panels to discover and overcome the obstacles associated with damage detection in the RCC material. Optimum combinations of custom ultrasonic probes and data analyses were merged with the inspection procedures needed to

  12. Laboratory stand for examination of the operational thermal parameters of polyvalent system for heating, cooling and domestic hot water supply using renewable energy sources

    International Nuclear Information System (INIS)

    Zlateva, Merima

    2014-01-01

    The report presents the structure of an universal laboratory stand for determine the operating parameters of a polyvalent system for utilization of renewable energy sources. The system is a combination of three modules using different technologies for renewable sources – solar energy, atmospheric air and biomass, incorporated in a common heat accumulator. The structural scheme permits the possibility to use the stand in different operating modes, to demonstrate the feasibility of using any one of the renewable energy sources both individually and in various combinations. The author express gratitude to the partners of the companies Robert Bosch Bulgaria Ltd, Ahi Carrier Bulgaria and Eratermtotal, with whose generous support is build the stand. Key words: Renewable energy sources (RES), Heating with RES, Biomass, Air to Water Heat pumps

  13. Pulsating Heat pipe Only for Space (PHOS): results of the REXUS 18 sounding rocket campaign

    International Nuclear Information System (INIS)

    Creatini, F; Guidi, G M; Belfi, F; Cicero, G; Fioriti, D; Di Prizio, D; Piacquadio, S; Becatti, G; Orlandini, G; Frigerio, A; Fontanesi, S; Nannipieri, P; Rognini, M; Morganti, N; Filippeschi, S; Di Marco, P; Fanucci, L; Baronti, F; Mameli, M; Manzoni, M

    2015-01-01

    Two Closed Loop Pulsating Heat Pipes (CLPHPs) are tested on board REXUS 18 sounding rocket in order to obtain data over a relatively long microgravity period (approximately 90 s). The CLPHPs are partially filled with FC-72 and have, respectively, an inner tube diameter larger (3 mm) and slightly smaller (1.6 mm) than the critical diameter evaluated in static Earth gravity conditions. On ground, the small diameter CLPHP effectively works as a Pulsating Heat Pipe (PHP): the characteristic slug and plug flow pattern forms inside the tube and the heat exchange is triggered by thermally driven self-sustained oscillations of the working fluid. On the other hand, the large diameter CLPHP works as a two- phase thermosyphon in vertical position and doesn't work in horizontal position: in this particular condition, the working fluid stratifies within the device as the surface tension force is no longer able to balance buoyancy. Then, the idea to test the CLPHPs in reduced gravity conditions: as the gravity reduces the buoyancy forces becomes less intense and it is possible to recreate the typical PHP flow pattern also for larger inner tube diameters. This allows to increase the heat transfer rate and, consequently, to decrease the overall thermal resistance. Even though it was not possible to experience low gravity conditions due to a failure in the yoyo de-spin system, the thermal response to the peculiar acceleration field (hyper-gravity) experienced on board are thoroughly described. (paper)

  14. Geothermal concept for energy efficient improvement of space heating and cooling in highly urbanized area

    Directory of Open Access Journals (Sweden)

    Vranjes Ana

    2015-01-01

    Full Text Available New Belgrade is a highly urbanized commercial and residential district of Belgrade lying on the alluvial plane of the Sava and the Danube rivers. The groundwater of the area is a geothermal resource that is usable through geothermal heat pumps (GHP. The research has shown that the “heat island effect” affects part of the alluvial groundwater with the average groundwater temperature of about 15.5°C, i.e. 2°C higher than the one in less urbanized surroundings. Based on the measured groundwater temperatures as well as the appraisal of the sustainable aquifer yield, the available thermal power of the resource is estimated to about 29MWt. The increasing urbanization trend of the New Belgrade district implies the growing energy demands that may partly be met by the available groundwater thermal power. Taking into consideration the average apartment consumption of 80 Wm-2, it is possible to heat about 360,000 m2 and with the consumption efficiency of 50 Wm-2, it would be possible to heat over 570,000 m2. Environmental and financial aspects were considered through the substitution of conventional fuels and the reduction of greenhouse gas emission as well as through the optimization of the resource use.

  15. Solar space heating for the visitors' center, Stephens College, Columbia, Missouri. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Henley, Marion

    1980-06-01

    This document is the final report of the solar energy system located at the Visitors' Center on the Stephens College Campus, Columbia, Missouri. The system is installed in a four-story, 15,000 square foot building designed to include the college's Admission Office, nine guest rooms for overnight lodging for official guests of the college, a two-story art gallery, and a Faculty Lounge. The solar energy system is an integral design of the building and utilizes 176 Honeywell/Lennox hydronic flat-plate collectors which use a 50% water-ethylene glycol solution and water-to-water heat exchanger. Solar heated water is stored in a 5000 gallon water storage tank located in the basement equipment room. A natural gas fired hot water boiler supplies hot water when the solar energy heat supply fails to meet the demand. The designed solar contribution is 71% of the heating load. The demonstration period for this project ends June 30, 1984.

  16. Phase-space interference in extensive and nonextensive quantum heat engines

    DEFF Research Database (Denmark)

    Hardal, Ali Ümit Cemal; Paternostro, Mauro; Mustecaplioglu, Ozgur E.

    2018-01-01

    Quantum interference is at the heart of what sets the quantum and classical worlds apart. We demonstrate that quantum interference effects involving a many-body working medium is responsible for genuinely nonclassical features in the performance of a quantum heat engine. The features with which...

  17. Economic Evaluation of a Solar Charged Thermal Energy Store for Space Heating

    OpenAIRE

    Melo, Manuel

    2013-01-01

    A thermal energy store corrects the misalignment of heating demand in the winter relative to solar thermal energy gathered in the summer. This thesis reviews the viability of a solar charged hot water tank thermal energy store for a school at latitude 56.25N, longitude -120.85W

  18. Performance demonstration of a high-power space-reactor heat-pipe design

    International Nuclear Information System (INIS)

    Merrigan, M.A.; Martinez, E.H.; Keddy, E.S.; Runyan, J.; Kemme, J.E.

    1983-01-01

    Performance of a 15.9-mm diam, 2-m long, artery heat pipe has been demonstrated at power levels to 22.6 kW and temperatures to 1500 0 K. The heat pipe employed lithium as a working fluid with distribution wicks and arteries fabricated from 400 mesh Mo-41 wt % Re screen. Molybdenum alloy (TZM) was used for the container. Peak axial power density attained in the testing was 19 kW/cm 2 at 1465 0 K. The corresponding radial flux density in the evaporator region of the heat pipe was 150 W/cm 2 . The extrapolated limit for the heat pipe at its 1500 0 K design point is 30 kW, corresponding to an axial flux density of 25 kW/cm 2 . Sonic and capillary limits for the design were investigated in the 1100 to 1500 0 K temperature range. Excellent agreement of measured and predicted temperature and power levels was observed

  19. General-purpose heat source project and space nuclear safety and fuels program. Progress reportt, January 1980

    International Nuclear Information System (INIS)

    Maraman, W.J.

    1980-04-01

    This formal monthly report covers the studies related to the use of 238 PuO 2 in radioisotopic power systems carried out for the Advanced Nuclear Systems and Projects Division of the Los Alamos Scientific Laboratory. The two programs involved are the general-purpose heat source development and space nuclear safety and fuels. Most of the studies discussed here are of a continuing nature. Results and conclusions described may change as the work continues. Published reference to the results cited in this report should not be made without the explicit permission of the person in charge of the work

  20. Laboratory Testing of Solar Combi System with Compact Long Term PCM Heat Storage

    DEFF Research Database (Denmark)

    Johansen, Jakob Berg; Englmair, Gerald; Dannemand, Mark

    2016-01-01

    To enable the transition from fossil fuels as a primary heat source for domestic hot water preparation and space heating solar thermal energy has great potential. The heat from the sun has the disadvantage that it is not always available when there is a demand. To solve this mismatch a thermal...... seasonal storage can be used to store excess heat from the summer to the winter when the demand is higher than the supply. Installing a long term thermal storage in a one family house it needs to be compact and sensible heat storages are not suitable. A latent heat storage with a phase change material (PCM...

  1. The impact of air-tightness in the retrofitting practice of low temperature heating

    OpenAIRE

    Wang, Qian; Holmberg, Sture

    2014-01-01

    In Sweden, the energy usage in existing residential buildings amounted to 147 TWh in 2012, equivalent to almost 40 % of the final overall national energy usage. Among all the end users in building service sectors, 60 % of the final energy in Sweden is used for space heating and domestic hot water (DHW) production in 2013. In order to reduce the supply temperature for space heating in existing buildings, combined approaches are favorably adopted: to reduce the net energy demand by air-tightnes...

  2. Solar assisted conditioning of residences with floor heating and ceiling cooling: review and simulation results

    OpenAIRE

    Egrican, Nilufer; Korkmaz, Adnan

    2015-01-01

    Solar or solar assisted heating and cooling systems are becoming widespread to reduce CO2 emissions. Efficient radiant space heating and cooling systems can be used to decrease the energy bills and improve occupant thermal comfort in buildings. This study uses the TRNSYS program, for the modeling and simulation of solar assisted radiant heating and cooling of a building with the domestic hot water supply, to examine the effects of various parameters on energy consumption. Calculations are per...

  3. Thermal analysis of heat storage canisters for a solar dynamic, space power system

    Science.gov (United States)

    Wichner, R. P.; Solomon, A. D.; Drake, J. B.; Williams, P. T.

    1988-01-01

    A thermal analysis was performed of a thermal energy storage canister of a type suggested for use in a solar receiver for an orbiting Brayton cycle power system. Energy storage for the eclipse portion of the cycle is provided by the latent heat of a eutectic mixture of LiF and CaF2 contained in the canister. The chief motivation for the study is the prediction of vapor void effects on temperature profiles and the identification of possible differences between ground test data and projected behavior in microgravity. The first phase of this study is based on a two-dimensional, cylindrical coordinates model using an interim procedure for describing void behavor in 1-g and microgravity. The thermal analysis includes the effects of solidification front behavior, conduction in liquid/solid salt and canister materials, void growth and shrinkage, radiant heat transfer across the void, and convection in the melt due to Marangoni-induced flow and, in 1-g, flow due to density gradients. A number of significant differences between 1-g and o-g behavior were found. This resulted from differences in void location relative to the maximum heat flux and a significantly smaller effective conductance in 0-g due to the absence of gravity-induced convection.

  4. Analysis on exergy consumption patterns for space heating in Slovenian buildings

    International Nuclear Information System (INIS)

    Dovjak, Mateja; Shukuya, Masanori; Olesen, Bjarne W.; Krainer, Ales

    2010-01-01

    Problem of high energy use for heating in Slovenian buildings is analyzed with exergy and energy analysis. Results of both are compared and discussed. Three cases of exterior building walls are located in three climatic zones in winter conditions. Results of energy analyses show that the highest heating energy demand appears in the case with less thermal insulation, especially in colder climate. If the comparison is made only on the energy supply and exergy supply, the results of exergy analysis are the same as those of energy analysis. The main difference appears, if the whole chain of supply and demand is taken into consideration. Exergy calculations enable us to analyze how much exergy is consumed in which part, from boiler to building envelope. They also reveal how much energy is supplied for the purpose of heating. Results show that insulation has much bigger effect than effect of boiler efficiency. However, the most effective solution is to improve building envelope together with boiler efficiency. Better thermal insulation also makes an important contribution to the improvement of thermal comfort conditions. It causes higher surface temperatures resulting in a larger warm radiant exergy emission rate and consequently better thermal comfort.

  5. Identification of potential for heat pumps for space heating of houses as replacement for oil-fired boilers; Afdaekning af potentiale for varmepumper til opvarmning af helaarshuse til erstatning for oliefyr

    Energy Technology Data Exchange (ETDEWEB)

    2011-11-15

    The analysis was intended to document and describe the realistic potential for conversion of oil-fired single-family houses to individual heat pumps of the type liquid / water and air / water. The assessment is based on a ''here and now'' condition and evaluates the potential from domestic economic factors. It is an overall analysis, and it has not been possible to analyze in detail the individual heat pump installation. The result of the analysis shows that for 75% of the houses it is not economically viable for the households to convert to a heat pump under the assumed conditions. In 25% of the houses with oil burner (and without access to public supply) it is considered economically viable to convert to a heat pump. About 1/3 of these houses can immediately install a heat pump, while 2/3 of the houses require substantial preparatory steps either in the form of investments in the building envelope and / or in the heat distribution the system. (LN)

  6. 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.

  7. The Importance of Green Spaces in Minimizing Urban Heat in The Istanbul Metropolitan Area

    Directory of Open Access Journals (Sweden)

    Çağdaş KUŞÇU ŞİMŞEK

    2012-04-01

    Full Text Available Increasing environmental and atmospheric pollution due to urbanization, industrialization and global warming is increasing with every passing day. Life in water, air and on land is threatened by environmental problems and disasters caused by this pollution. In addition to global climate change, changes also occur in urban microclimate and regional heat islands are occurring in urban areas. This dual effect and resulting vicious circle increasingly affect human health and natural life negatively. In this context, urban climate studies have come into question in recent years. Results have showed that increasing numbers of built-up areas are linked toincreases in urban temperature and conversely larger areas of vegetation improve the city’s ventilation and climatic comfort. The Istanbul Metropolitan Area is in a period of regeneration as it attempts to prepare for the expected earthquake and as a result of global dynamics. The resulting massive building campaigns and rapid destruction of green areas have a potential to trigger climatic threats. The effects of vegetation on the urban surface temperature in the Istanbul Metropolitan Area have contributed to the improved health construction strategies. Surface Heat Islands (SHI and Normalized Difference Vegetation Index (NDVI values were determined from remote sensing techniques. The dependent variable is temperature and independent variable is NDVI values and the regression analysis was carried out. Then the heat model for NDVI was established with decision tree. The results of regression analysis were R=0.452; R2= 20%; sig.=0.00 and so the analysis was significant in 95%. As a result of the analysis of the residential area of İstanbul, the difference between the expected temperature of the minimum and maximum vegetation clusters was calculated as 4.24.

  8. Ecosystem services and urban heat riskscape moderation: water, green spaces, and social inequality in Phoenix, USA.

    Science.gov (United States)

    Jenerette, G Darrel; Harlan, Sharon L; Stefanov, William L; Martin, Chris A

    2011-10-01

    Urban ecosystems are subjected to high temperatures--extreme heat events, chronically hot weather, or both-through interactions between local and global climate processes. Urban vegetation may provide a cooling ecosystem service, although many knowledge gaps exist in the biophysical and social dynamics of using this service to reduce climate extremes. To better understand patterns of urban vegetated cooling, the potential water requirements to supply these services, and differential access to these services between residential neighborhoods, we evaluated three decades (1970-2000) of land surface characteristics and residential segregation by income in the Phoenix, Arizona, USA metropolitan region. We developed an ecosystem service trade-offs approach to assess the urban heat riskscape, defined as the spatial variation in risk exposure and potential human vulnerability to extreme heat. In this region, vegetation provided nearly a 25 degrees C surface cooling compared to bare soil on low-humidity summer days; the magnitude of this service was strongly coupled to air temperature and vapor pressure deficits. To estimate the water loss associated with land-surface cooling, we applied a surface energy balance model. Our initial estimates suggest 2.7 mm/d of water may be used in supplying cooling ecosystem services in the Phoenix region on a summer day. The availability and corresponding resource use requirements of these ecosystem services had a strongly positive relationship with neighborhood income in the year 2000. However, economic stratification in access to services is a recent development: no vegetation-income relationship was observed in 1970, and a clear trend of increasing correlation was evident through 2000. To alleviate neighborhood inequality in risks from extreme heat through increased vegetation and evaporative cooling, large increases in regional water use would be required. Together, these results suggest the need for a systems evaluation of the

  9. Analysis on exergy consumption patterns for space heating in Slovenian buildings

    DEFF Research Database (Denmark)

    Dovjak, Mateja; Shukuya, Masanori; Olesen, Bjarne W.

    2010-01-01

    and demand is taken into consideration. Exergy calculations enable us to analyze how much exergy is consumed in which part, from boiler to building envelope. They also reveal how much energy is supplied for the purpose of heating. Results show that insulation has much bigger effect than effect of boiler...... efficiency. However, the most effective solution is to improve building envelope together with boiler efficiency. Better thermal insulation also makes an important contribution to the improvement of thermal comfort conditions. It causes higher surface temperatures resulting in a larger warm radiant exergy...... emission rate and consequently better thermal comfort....

  10. Half-Space Temperature Field with a Movable Thermally Thin-Coated Boundary Under External Heat Flux

    Directory of Open Access Journals (Sweden)

    P. A. Vlasov

    2014-01-01

    Full Text Available In engineering practice analytical methods of the mathematical theory of heat conduction hold a special place. This is due to many reasons, in particular, because of the fact that the solutions of the relevant problems represented in analytically closed form, can be used not only for a parametric analysis of the studied temperature field and to explore the specific features of its formation, but also to test the developed computational algorithms, which are aimed at solving real-world application heat and mass transfer problems. Difficulties arising when using the analytical mathematical theory methods of heat conduction in practice are well known. Also they are significantly exacerbated if the boundaries of the system under study are movable, even in the simplest case, when the law of motion is known.The main goal of the conducted research is to have an analytically closed-form problem solution for finding the orthotropic half-space temperature field, a boundary of which has thermally thin coating exposed to extremely concentrated stationary external heat flux and uniformly moves parallel to itself.The assumption that the covering of the boundary is thermally thin, allowed to realize the idea of \\concentrated capacity", that is to accept the hypothesis that the mean-thickness coating temperature is equal to the temperature of its boundaries. This assumption allowed us to reduce the problem under consideration to a mixed problem for a parabolic equation with a specific boundary condition.The Hankel integral transform of zero order with respect to the radial variable and the Laplace transform with respect to the temporal variable were used to solve the reduced problem. These techniques have allowed us to submit the required solution as an iterated integral.

  11. Domestic Ice Breaking Simulation Model User Guide

    Science.gov (United States)

    2012-04-01

    Waterways Management Branch GPS Global Positioning System HHO home heating oil LCA Lake Carriers’ Association MAR USCG Domestic Icebreaking...These four types of cargo are further grouped into two broader categories, namely, Home Heating Oil ( HHO ) shipments or Non- HHO shipments. The data

  12. Electrónica de potencia para el calentamiento por inducción doméstico: revisión del estado del arte Power Electronics for Domestic Induction Heating: a Review

    Directory of Open Access Journals (Sweden)

    John N Hincapié

    2013-11-01

    Full Text Available Este trabajo presenta la revisión de la literatura que relaciona los desarrollos de los sistemas de calentamiento por inducción. Inicialmente, se presenta una contextualización de la forma general de funcionamiento y se concentra en las características particulares para uso doméstico y de manera más específica en la electrónica de potencia. Se presentan los principios de operación, las topologías de inversores resonantes más usadas (serie, paralelo, híbrida, cuasi-resonante y de un solo interruptor, las estrategias de modulación, estrategias de control usando modulación de frecuencia, por ancho de pulso y por densidad de pulso y las metodologías de conmutación (suave y forzada. Finalmente, se hace un pequeño análisis sobre las áreas donde aún es necesaria la investigación tales como sistemas de calefacción por inducción con múltiples salidas, topologías de inversores de un solo interruptor y los inversores cuasi-resonantes.This work presents a technical review about the development of the domestic induction heating systems. Initially, this paper presents basic concepts and general principles of induction heating and it focuses in the particular characteristics for domestic appliances and specifically in the power electronics. It shows the operation principles, the topologies of resonant inverter most used (serial, parallel, hybrid, quasi-resonant, and single-switch, the switching strategies, the control strategies using frequency modulation, width modulation, and pulse density, and the switching methodologies (soft and hard. Finally, it is done a brief analysis on the areas where further research is still needed such as multiple-outputs induction heating systems, single switch inverter topologies, and quasiresonant inverters.

  13. Energy wood. Part 2b: Wood pellets and pellet space-heating systems

    International Nuclear Information System (INIS)

    Nussbaumer, T.

    2002-01-01

    The paper gives an overview on pellet utilization including all relevant process steps: Potential and properties of saw dust as raw material, pellet production with drying and pelletizing, standardization of wood pellets, storage and handling of pellets, combustion of wood pellets in stoves and boilers and applications for residential heating. In comparison to other wood fuels, wood pellets show several advantages: Low water content and high heating value, high energy density, and homogeneous properties thus enabling stationary combustion conditions. However, quality control is needed to ensure constant properties of the pellets and to avoid the utilization of contaminated raw materials for the pellet production. Typical data of efficiencies and emissions of pellet stoves and boilers are given and a life cycle analysis (LCA) of wood pellets in comparison to log wood and wood chips is described. The LCA shows that wood pellets are advantageous thanks to relatively low emissions. Hence, the utilization of wood pellet is proposed as a complementary technology to the combustion of wood chips and log wood. Finally, typical fuel cost of wood pellets in Switzerland are given and compared with light fuel oil. (author)

  14. A new test procedure to evaluate the performance of substations for collective heating systems

    Science.gov (United States)

    Baetens, Robin; Verhaert, Ivan

    2017-11-01

    The overall heat demand of a single dwelling, existing out of space heating and domestic hot water production, decreases due to higher insulation rates. Because of this, investing in efficient and renewable heat generation becomes less interesting. Therefore, to incorporate renewables or residual heat on a larger scale, district heating or collective heating systems grow in importance. Within this set-up, the substation is responsible for the interaction between local demand for comfort and overall energy performance of the collective heating system. Many different configurations of substations exist, which influence both local comfort and central system performance. Next to that, also hybrids exist with additional local energy input. To evaluate performance of such substations, a new experimental-based test procedure is developed in order to evaluate these different aspects, characterized by the two roles a substation has, namely as heat generator and as heat consumer. The advantage of this approach is that an objective comparison between individual and central systems regarding performance on delivering local comfort can be executed experimentally. The lab set-up consists out of three different subsystems, namely the central system, the domestic hot water consumption and the local space heating. The central system can work with different temperature regimes and control strategies, as these aspects have proven to have the largest influence on actual performance. The domestic hot water system is able to generate similar tap profiles according to eco-design regulation for domestic hot water generation. The space heating system is able to demand a modular heat load.

  15. A new test procedure to evaluate the performance of substations for collective heating systems

    Directory of Open Access Journals (Sweden)

    Baetens Robin

    2017-01-01

    Full Text Available The overall heat demand of a single dwelling, existing out of space heating and domestic hot water production, decreases due to higher insulation rates. Because of this, investing in efficient and renewable heat generation becomes less interesting. Therefore, to incorporate renewables or residual heat on a larger scale, district heating or collective heating systems grow in importance. Within this set-up, the substation is responsible for the interaction between local demand for comfort and overall energy performance of the collective heating system. Many different configurations of substations exist, which influence both local comfort and central system performance. Next to that, also hybrids exist with additional local energy input. To evaluate performance of such substations, a new experimental-based test procedure is developed in order to evaluate these different aspects, characterized by the two roles a substation has, namely as heat generator and as heat consumer. The advantage of this approach is that an objective comparison between individual and central systems regarding performance on delivering local comfort can be executed experimentally. The lab set-up consists out of three different subsystems, namely the central system, the domestic hot water consumption and the local space heating. The central system can work with different temperature regimes and control strategies, as these aspects have proven to have the largest influence on actual performance. The domestic hot water system is able to generate similar tap profiles according to eco-design regulation for domestic hot water generation. The space heating system is able to demand a modular heat load.

  16. Frictional Heating During Sliding of two Semi-Spaces with Arbitrary Thermal Nonlinearity

    Directory of Open Access Journals (Sweden)

    Och Ewa

    2014-12-01

    Full Text Available Analytical and numerical solution for transient thermal problems of friction were presented for semi limited bodies made from thermosensitive materials in which coefficient of thermal conductivity and specific heat arbitrarily depend on the temperature (materials with arbitrary non-linearity. With the constant power of friction assumption and imperfect thermal contact linearization of nonlinear problems formulated initial-boundary thermal conductivity, using Kirchhoff transformation is partial. In order to complete linearization, method of successive approximations was used. On the basis of obtained solutions a numerical analysis of two friction systems in which one element is constant (cermet FMC-845 and another is variable (grey iron ChNMKh or aluminum-based composite alloy AL MMC was conducted

  17. Numerical Simulation for Magneto Nanofluid Flow Through a Porous Space with Melting Heat Transfer

    Science.gov (United States)

    Hayat, T.; Shah, Faisal; Alsaedi, A.; Waqas, M.

    2018-05-01

    Melting heat transfer and non-Darcy porous medium effects in MHD stagnation point flow toward a stretching surface of variable thickness are addressed. Brownian motion and thermophoresis in nanofluid modeling are retained. Zero mass flux condition for concentration at surface is imposed. The problem of ordinary differential system are analyzed numerically through shooting technique. Graphically results of various physical variables on the velocity, temperature and concentration are studied. Skin friction coefficient local Nusselt number and Sherwood number are also addressed through tabulated values. The results described here illustrate that the velocity field is higher via larger melting parameter. However reverse situation is examined for Hartman number. Moreover the influence of thermophoresis parameter on temperature and concentration is noted similar.

  18. Numerical Simulation for Magneto Nanofluid Flow Through a Porous Space with Melting Heat Transfer

    Science.gov (United States)

    Hayat, T.; Shah, Faisal; Alsaedi, A.; Waqas, M.

    2018-02-01

    Melting heat transfer and non-Darcy porous medium effects in MHD stagnation point flow toward a stretching surface of variable thickness are addressed. Brownian motion and thermophoresis in nanofluid modeling are retained. Zero mass flux condition for concentration at surface is imposed. The problem of ordinary differential system are analyzed numerically through shooting technique. Graphically results of various physical variables on the velocity, temperature and concentration are studied. Skin friction coefficient local Nusselt number and Sherwood number are also addressed through tabulated values. The results described here illustrate that the velocity field is higher via larger melting parameter. However reverse situation is examined for Hartman number. Moreover the influence of thermophoresis parameter on temperature and concentration is noted similar.

  19. A potential candidate for the sustainable and reliable domestic energy generation–Thermoelectric cogeneration system

    International Nuclear Information System (INIS)

    Zheng, X.F.; Yan, Y.Y.; Simpson, K.

    2013-01-01

    Due to being solid-state, noiseless and maintenance free, thermoelectric devices have found wide applications in different areas since they were discovered over 180 years ago. The applications are concerned with environment-friendly refrigeration and power generation in transportation tools, industrial utilities, military devices, medical services and space applications. It is utilisation of waste heat in varying applications that make the modules particularly attractive. Nevertheless, despite a few academic papers, there has not been extensive use in the domestic sector. A concept of thermoelectric cogeneration system (‘TCS’) is proposed to highlight the direction for enhancing the sustainability by improving the energy efficiency in domestic sector. Compared to the thermoelectric systems used in other areas which only uses the part of converted energy but wastes the unconverted part by dissipating it into the environment, the system presented here maximally recover the available heat by generating electrical power and producing hot water simultaneously. The viability of this system concept is evaluated on a bench-scale experimental prototype. The outputs of electrical power and hot water have been investigated at different temperature difference. The cost saving potential and cost recovery period have been estimated using the available heat sources in domestic sector. The results intend to provide reference for developing the real-scale domestic thermoelectric cogeneration system and show the potential benefits

  20. Electron velocity-space diffusion in a micro-unstable ECRH [electron cyclotron resonance heated] mirror plasma

    International Nuclear Information System (INIS)

    Hokin, S.A.

    1987-09-01

    An experimental study of the velocity-space diffusion of electrons in an electron cyclotron resonance heated (ECRH) mirror plasma, in the presence of micro-unstable whistler rf emission, is presented. It is found that the dominant loss mechanism for hot electrons is endloss produced by rf diffusion into the mirror loss cone. In a standard case with 4.5 kW of ECRH power, this loss limits the stored energy to 120 J with an energy confinement time of 40 ms. The energy confinement time associated with collisional scattering is 350 ms in this case. Whistler microinstability rf produces up to 25% of the rf-induced loss. The hot electron temperature is not limited by loss of adiabaticity, but by rf-induced loss of high energy electrons, and decreases with increasing rf power in strong diffusion regimes. Collisional loss is in agreement with standard scattering theory. No super-adiabatic effects are clearly seen. Experiments in which the vacuum chamber walls are lined with microwave absorber reveal that single pass absorption is limited to less than 60%, whereas experiments with reflecting walls exhibit up to 90% absorption. Stronger diffusion is seen in the latter, with a hot electron heating rate which is twice that of the absorber experiments. This increase in diffusion can be produced by two distinct aspects of wall-reflected rf: the broader spatial rf profile, which enlarges the resonant region in velocity space, or a reduction in super-adiabatic effects due to randomization of the electron gyrophase. Since no other aspects of super-adiabaticity are observed, the first mechanism appears more likely. 39 refs., 54 figs

  1. The Effect of Tree Spacing and Size in Urban Areas: Strategies for Mitigating High Temperature in Urban Heat Islands

    Science.gov (United States)

    Berry, R.; Shandas, V.; Makido, Y.

    2017-12-01

    Many cities are unintentionally designed to be heat sinks, which absorb the sun's short-wave radiation and reemit as long-wave radiation. Long time reorganization of this `urban heat island' (UHI) phenomena has led researchers and city planners into developing strategies for reducing ambient temperatures through urban design. Specifically, greening areas have proven to reduce the temperature in UHI's, including strategies such as green streets, green facades, and green roofs have been implemented. Among the scientific community there is promoted study of how myriad greening strategies can reduce temperature, relatively limited work has focused on the distribution, density, and quantity of tree campaigns. This paper examines how the spacing and size of trees reduce temperatures differently. A major focus of the paper is to understand how to lower the temperature through tree planting, and provide recommendations to cities that are attempting to solve their own urban heat island issues. Because different cities have different room for planting greenery, we examined which strategies are more efficient given an area constraint. Areas that have less available room might not be able to plant a high density of trees. We compared the different experimental groups varying in density and size of trees against the control to see the effect the trees had. Through calibration with local weather stations, we used a micrometeorology program (ENVI-Met) to model and simulate the different experimental models and how they affect the temperature. The results suggest that some urban designs can reduce ambient temperatures by over 7 0C, and the inclusion of large form trees have the greatest contribution, by reducing temperatures over 15 0C. The results suggest that using specific strategies that combine placement of specific tree configurations with alternative distribution of urban development patterns can help to solve the current challenges of UHI's, and thereby support management

  2. Space and time variability of heating requirements for greenhouse tomato production in the Euro-Mediterranean area.

    Science.gov (United States)

    Mariani, Luigi; Cola, Gabriele; Bulgari, Roberta; Ferrante, Antonio; Martinetti, Livia

    2016-08-15

    The Euro-Mediterranean area is the seat of a relevant greenhouse activity, meeting the needs of important markets. A quantitative assessment of greenhouse energy consumption and of its variability in space and time is an important decision support tool for both greenhouse-sector policies and farmers. A mathematical model of greenhouse energy balance was developed and parameterized for a state-of-the-art greenhouse to evaluate the heating requirements for vegetables growing. Tomato was adopted as reference crop, due to its high energy requirement for fruit setting and ripening and its economic relevance. In order to gain a proper description of the Euro-Mediterranean area, 56 greenhouse areas located within the ranges 28°N-72°N and 11°W-55°E were analyzed over the period 1973-2014. Moreover, the two 1973-1987 and 1988-2014 sub-periods were separately studied to describe climate change effects on energy consumption. Results account for the spatial variability of energy needs for tomato growing, highlighting the strong influence of latitude on the magnitude of heat requirements. The comparison between the two selected sub-periods shows a decrease of energy demand in the current warm phase, more relevant for high latitudes. Finally, suggestions to reduce energy consumptions are provided. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Making it not too obvious. The effect of ambient light feedback on space heating energy consumption

    Energy Technology Data Exchange (ETDEWEB)

    Maan, S.; Merkus, B.; Ham, J.; Midden, C. [Human-Technology Interaction, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven (Netherlands)

    2011-03-15

    Earlier research investigating persuasive technology - technology designed to influence human behavior or attitude - indicates that persuasive technology can stimulate energy efficient behavior. However, most applications of persuasive technology need people's focal attention to be successful, and people may often not have these cognitive resources available. The current research investigates a form of persuasive technology that is less obvious and easier to process: ambient lighting as persuasive technology. In an experimental study, participants could conserve energy while setting temperatures on a central heating panel and receive feedback about their energy consumption in each task. We tested the effect of feedback through a lamp that gradually changed color dependent on energy consumption and compared these effects to more widely used factual feedback. Half of the participants received lighting feedback, and half of the participants received numerical feedback. To investigate whether ambient feedback is easier to process than numerical feedback, half of the participants performed a cognitive load task in addition to the focal task. Results indicated that feedback through lighting has stronger persuasive effects than numerical feedback. Furthermore, ambient lighting feedback seemed easier to process than numerical feedback because cognitive load interfered with processing numerical feedback, but not with processing lighting feedback. Implications for theory and design of energy consumption feedback systems, persuasive lighting, and (ambient) persuasive technology are discussed.

  4. Graphite fiber/copper matrix composites for space power heat pipe fin applications

    International Nuclear Information System (INIS)

    Mcdanels, D.L.; Baker, K.W.; Ellis, D.L.

    1991-01-01

    High specific thermal conductivity (thermal conductivity divided by density) is a major design criterion for minimizing system mass for space power systems. For nuclear source power systems, graphite fiber reinforced copper matrix (Gr/Cu) composites offer good potential as a radiator fin material operating at service temperatures above 500 K. Specific thermal conductivity in the longitudinal direction is better than beryllium and almost twice that of copper. The high specific thermal conductivity of Gr/Cu offers the potential of reducing radiator mass by as much as 30 percent. Gr/Cu composites also offer the designer a range of available properties for various missions and applications. The properties of Gr/Cu are highly anisotropic. Longitudinal elastic modulus is comparable to beryllium and about three times that of copper. Thermal expansion in the longitudinal direction is near zero, while it exceeds that of copper in the transverse direction. 5 refs

  5. Heat resistant materials and their feasibility issues for a space nuclear transportation system

    International Nuclear Information System (INIS)

    Olsen, C.S.

    1991-01-01

    A number of nuclear propulsion concepts based on solid-core nuclear propulsion are being evaluated for a nuclear propulsion transportation system to support the Space Exploration Initiative (SEI) involving the reestablishment of a manned lunar base and the subsequent exploration of Mars. These systems will require high-temperature materials to meet the operating conditions with appropriate reliability and safety built into these systems through the selection and testing of appropriate materials. The application of materials for nuclear thermal propulsion (NTP) and nuclear electric propulsion (NEP) systems and the feasibility issues identified for their use will be discussed. Some mechanical property measurements have been obtained, and compatibility tests were conducted to help identify feasibility issues. 3 refs., 1 fig., 4 tabs

  6. Structural assessment of a space station solar dynamic heat receiver thermal energy storage canister

    Science.gov (United States)

    Thompson, R. L.; Kerslake, T. W.; Tong, M. T.

    1988-01-01

    The structural performance of a space station thermal energy storage (TES) canister subject to orbital solar flux variation and engine cold start up operating conditions was assessed. The impact of working fluid temperature and salt-void distribution on the canister structure are assessed. Both analytical and experimental studies were conducted to determine the temperature distribution of the canister. Subsequent finite element structural analyses of the canister were performed using both analytically and experimentally obtained temperatures. The Arrhenius creep law was incorporated into the procedure, using secondary creep data for the canister material, Haynes 188 alloy. The predicted cyclic creep strain accumulations at the hot spot were used to assess the structural performance of the canister. In addition, the structural performance of the canister based on the analytically determined temperature was compared with that based on the experimentally measured temperature data.

  7. Experimental study on pool boiling critical heat flux in inclined confined spaces

    International Nuclear Information System (INIS)

    Wen Qinglong; Chen Jun; Zhao Hua

    2011-01-01

    CHF experiments in confined spaces are performed for near-saturated demineralized water at atmospheric pressure with gap sizes of 3 mm, 5 mm and 8 mm, and inclination angles of 0°, 5°, 10°, 15°, 20°, and 30°. Analysis of CHF data shows that CHF decreases as the inclination angle changes from 300 to full downward facing position (0°) and increases as the gap size varies from 3 mm to 8 mm. In the present study, certain transition angles are also identified for different gap sizes. For the gap sizes of 3 mm, 5 mm and 8 mm, the transition angles are found to be 10°, 15° and 20°, respectively. (authors)

  8. Space Launch System Base Heating Test: Tunable Diode Laser Absorption Spectroscopy

    Science.gov (United States)

    Parker, Ron; Carr, Zak; MacLean, Mathew; Dufrene, Aaron; Mehta, Manish

    2016-01-01

    This paper describes the Tunable Diode Laser Absorption Spectroscopy (TDLAS) measurement of several water transitions that were interrogated during a hot-fire testing of the Space Launch Systems (SLS) sub-scale vehicle installed in LENS II. The temperature of the recirculating gas flow over the base plate was found to increase with altitude and is consistent with CFD results. It was also observed that the gas above the base plate has significant velocity along the optical path of the sensor at the higher altitudes. The line-by-line analysis of the H2O absorption features must include the effects of the Doppler shift phenomena particularly at high altitude. The TDLAS experimental measurements and the analysis procedure which incorporates the velocity dependent flow will be described.

  9. Reducing cell-to-cell spacing for large-format lithium ion battery modules with aluminum or PCM heat sinks under failure conditions

    International Nuclear Information System (INIS)

    Coleman, Brittany; Ostanek, Jason; Heinzel, John

    2016-01-01

    Highlights: • Finite element analysis to evaluate heat sinks for large format li-ion batteries. • Solid metal heat sink and composite heat sink (metal filler and wax). • Transient simulations show response from rest to steady-state with normal load. • Transient simulations of two different failure modes were considered. • Significance of spacing, material properties, interface quality, and phase change. - Abstract: Thermal management is critical for large-scale, shipboard energy storage systems utilizing lithium-ion batteries. In recent years, there has been growing research in thermal management of lithium-ion battery modules. However, there is little information available on the minimum cell-to-cell spacing limits for indirect, liquid cooled modules when considering heat release during a single cell failure. For this purpose, a generic four-cell module was modeled using finite element analysis to determine the sensitivity of module temperatures to cell spacing. Additionally, the effects of different heat sink materials and interface qualities were investigated. Two materials were considered, a solid aluminum block and a metal/wax composite block. Simulations were run for three different transient load profiles. The first profile simulates sustained high rate operation where the system begins at rest and generates heat continuously until it reaches steady state. And, two failure mode simulations were conducted to investigate block performance during a slow and a fast exothermic reaction, respectively. Results indicate that composite materials can perform well under normal operation and provide some protection against single cell failure; although, for very compact designs, the amount of wax available to absorb heat is reduced and the effectiveness of the phase change material is diminished. The aluminum block design performed well under all conditions, and showed that heat generated during a failure is quickly dissipated to the coolant, even under the

  10. Flexible demand in the GB domestic electricity sector in 2030

    International Nuclear Information System (INIS)

    Drysdale, Brian; Wu, Jianzhong; Jenkins, Nick

    2015-01-01

    Highlights: • Annual domestic demand by category and daily flexible load profiles are shown to 2030. • Valuable flexible demand requires loads to be identifiable, accessible, and useful. • The extent of flexible demand varies significantly on a diurnal and seasonal basis. • Barriers to accessing domestic demand include multiple low value loads and apathy. • Existing market structure a barrier to fully rewarding individual load flexibility. - Abstract: In order to meet greenhouse gas emissions targets the Great Britain (GB) future electricity supply will include a higher fraction of non-dispatchable generation, increasing opportunities for demand side management to maintain a supply/demand balance. This paper examines the extent of flexible domestic demand (FDD) in GB, its usefulness in system balancing and appropriate incentives to encourage consumers to participate. FDD, classified as electric space and water heating (ESWH), and cold and wet appliances, amounts to 59 TW h in 2012 (113 TW h total domestic demand) and is calculated to increase to 67 TW h in 2030. Summer and winter daily load profiles for flexible loads show significant seasonal and diurnal variations in the total flexible load and between load categories. Low levels of reflective consumer engagement with electricity consumption and a resistance to automation present barriers to effective access to FDD. A value of £1.97/household/year has been calculated for cold appliance loads used for frequency response in 2030, using 2013 market rates. The introduction of smart meters in GB by 2020 will allow access to FDD for system balancing. The low commercial value of individual domestic loads increases the attractiveness of non-financial incentives to fully exploit FDD. It was shown that appliance loads have different characteristics which can contribute to an efficient power system in different ways

  11. Space heating in buildings: thermal diagnosis of an industrial building; Chauffage des batiments: bilan thermique d`un batiment industriel

    Energy Technology Data Exchange (ETDEWEB)

    Brunet, R.

    1996-12-31

    The various heat transfer equations used for calculations in thermal diagnosis of an industrial building are reviewed: calculation of the heat losses through walls as a function of building materials, calculation of the energy consumption for heating fresh air (as a function of the air pollution rate in the building), calculation of the total heat losses, the heating energy demand and the annual energy consumption. Data concerning building materials characteristics, insulation and heating loads in the various regions of France, are also presented

  12. Effects of atmospheric variability on energy utilization and conservation. [Space heating energy demand modeling; Program HEATLOAD

    Energy Technology Data Exchange (ETDEWEB)

    Reiter, E.R.; Johnson, G.R.; Somervell, W.L. Jr.; Sparling, E.W.; Dreiseitly, E.; Macdonald, B.C.; McGuirk, J.P.; Starr, A.M.

    1976-11-01

    Research conducted between 1 July 1975 and 31 October 1976 is reported. A ''physical-adaptive'' model of the space-conditioning demand for energy and its response to changes in weather regimes was developed. This model includes parameters pertaining to engineering factors of building construction, to weather-related factors, and to socio-economic factors. Preliminary testing of several components of the model on the city of Greeley, Colorado, yielded most encouraging results. Other components, especially those pertaining to socio-economic factors, are still under development. Expansion of model applications to different types of structures and larger regions is presently underway. A CRT-display model for energy demand within the conterminous United States also has passed preliminary tests. A major effort was expended to obtain disaggregated data on energy use from utility companies throughout the United States. The study of atmospheric variability revealed that the 22- to 26-day vacillation in the potential and kinetic energy modes of the Northern Hemisphere is related to the behavior of the planetary long-waves, and that the midwinter dip in zonal available potential energy is reflected in the development of blocking highs. Attempts to classify weather patterns over the eastern and central United States have proceeded satisfactorily to the point where testing of our method for longer time periods appears desirable.

  13. Critical heat flux tests for self-spaced square finned 7 fuel rod bundle

    International Nuclear Information System (INIS)

    Moon, Sang Ki; Chun, Se Young; Choi, Ki Young; Park, Jong Kuk; Hwang, Dae Hyun; Zee, Sung Quun; Kim, Keung Koo

    2001-09-01

    Now, KAERI is developing a new advanced reactor aimed at achieving highly enhanced safety and reliability, and improved economics. SSF (Self-Spaced Square Finned) fuel rod bundle is considered as a suitable one for the new advanced reactor. The SSF fuel rods have rectangular shapes and four fins at the corners, and are arranged in triangular geometry. While the SSF fuel rod bundle is considered to have enhanced cooling efficiency, the correlations used for commercial PWR might be able to be applied. The application results of some conventional correlations show that the SSF fuel rod bundle show an enhanced CHF performance about 10 to 40 %. When some conventional CHF correlations are applied to CHF data with a similar geometry to the SSF fuel rod bundle, conventional CHF correlations including a correlation developed in Russia are judged not to be suitable for the development of SSF fuel rod bundle and for the use in a safety analysis code. From CHF experiments for SSF 7 fuel rod bundle performed in KAERI, the following results are obtained: the CHF increases with increasing mass flux, and the CHF increasing rate decreases at high mass flux conditions. The exit quality decreases with increasing mass flux. The overall effect of the mass flux on the CHF and exit quality coincides with previous understanding. Compared to the CHF data of IPPE with the same system pressure and inlet temperature, the CHF data of KAERI show the similar values. Thus, the reliability of IPPE CHF data can be confirmed indirectly

  14. Energy Performance and Economic Evaluation of Heat Pump/Organic Rankine Cycle System with Sensible Thermal Storage

    DEFF Research Database (Denmark)

    Carmo, C.; Dumont, O.; Nielsen, M. P.

    2016-01-01

    that consists of a ground-source heat pump with possibility of reversing operation as an ORC power cycle combined with solar heating in a single-family building is introduced. The ORC mode enables the use of solar energy in periods of no heat energy demand and reverses the heat pump cycle to supply electrical...... power.This paper combines a dynamic model based on empirical data of the HP/ORC system with lessons learned from 140 heat pump installations operating in real-life conditions in a cold climate. These installations were monitored for a period up to 5 years.Based on the aforementioned model and real......-life conditions knowledge, the paper considers two different sensible energy storage (TES) configurations for the reversible heat pump/organic Rankine cycle (HP/ORC) system: a buffer tank for both space heating and domestic hot water and a hot water storage tank used exclusively for domestic hot water...

  15. Earliest Deadline Control of a Group of Heat Pumps with a Single Energy Source

    Directory of Open Access Journals (Sweden)

    Jiří Fink

    2016-07-01

    Full Text Available In this paper, we develop and investigate the optimal control of a group of 104 heat pumps and a central Combined Heat and Power unit (CHP. The heat pumps supply space heating and domestic hot water to households. Each house has a buffer for domestic hot water and a floor heating system for space heating. Electricity for the heat pumps is generated by a central CHP unit, which also provides thermal energy to a district heating system. The paper reviews recent smart grid control approaches for central and distributed levels. An online algorithm is described based on the earliest deadline first theory that can be used on the aggregator level to control the CHP and to give signals to the heat pump controllers if they should start or should wait. The central controller requires only a limited amount of privacy-insensitive information from the heat pump controllers about their deadlines, which the heat pump controllers calculate for themselves by model predictions. In this way, a robust heat pump and CHP control is obtained, which is able to minimize energy demand and results in the desired thermal comfort for the households. The simulations demonstrate fast computation times due to minor computational and communication overheads.

  16. Performance analysis of diesel engine heat pump incorporated with heat recovery

    International Nuclear Information System (INIS)

    Shah, N.N.; Huang, M.J.; Hewitt, N.J.

    2016-01-01

    Highlights: • Diesel engine heat pump with heat recovery. • Water-to-water source heat pump based on R134a. • Possibility for different flow temperature for heat distribution system. • Possible retrofit application in off-gas or weak electricity network area. • Potential to diversify use of fossil fuel, primary energy and CO_2 emission savings. - Abstract: This paper presents experimental study of diesel engine heat pump (DEHP) system to find potential as retrofit technology in off-gas or weak electricity network area to replace existing gas/oil/electric heating system in domestic sector. Test set-up of diesel engine driven water-to-water heat pump system was built which included heat recovery arrangement from the engine coolant & exhaust gas. The system was designed to meet typical house heating demand in Northern Ireland. Performance of DEHP was evaluated to meet house-heating demand at different flow temperature (35, 45, 55 & 65 °C), a typical requirement of underfloor space heating, medium/high temperature radiators and domestic hot water. The performance was evaluated against four-evaporator water inlet temperature (0, 5, 10 & 15 °C) and at three different engine speed 1600, 2000 & 2400 rpm. Experiment results were analysed in terms of heating/cooling capacity, heat recovery, total heat output, primary energy ratio (PER), isentropic efficiency, etc. Test results showed that DEHP is able to meet house-heating demand with help of heat recovery with reduced system size. Heat recovery contributed in a range of 22–39% in total heat output. It is possible to achieve high flow temperature in a range of 74 °C with help of heat recovery. Overall system PER varied in a range of 0.93–1.33. Speed increment and flow temperature has significant impact on heat recovery, total heat output and PER. A case scenario with different flow temperature to match house-heating demand has been presented to show working potential with different heat distribution system

  17. Heat exchanger

    Science.gov (United States)

    Daman, Ernest L.; McCallister, Robert A.

    1979-01-01

    A heat exchanger is provided having first and second fluid chambers for passing primary and secondary fluids. The chambers are spaced apart and have heat pipes extending from inside one chamber to inside the other chamber. A third chamber is provided for passing a purge fluid, and the heat pipe portion between the first and second chambers lies within the third chamber.

  18. Space Transportation Analysis and Design (Reissue A)

    Science.gov (United States)

    1993-02-17

    RECOVERABLE LAUNCH VEHICLES ..................... 3-12 1. Domestic (STS Space Shuttle) ....................................... 3-12 2. Foreign (CIS Energia ...affects solar heating of the spacecraft and the availability of solar energy for generating spacecraft power. 2-1 Table 2-1. Typical Orbits and...Foreign (CIS Energia Buran) The CIS Energia , which became operational in 1987, was developed to launch a variety of heavy payloads including the Buran

  19. Well posedness and regularity for heat equation with the initial condition in weighted Orlitz-Slobodetskii space subordinated to Orlicz space like lambda (log lambda0alpha and the logarithmic weight

    Czech Academy of Sciences Publication Activity Database

    Kałamajska, A.; Krbec, Miroslav

    2015-01-01

    Roč. 28, č. 3 (2015), s. 677-713 ISSN 1139-1138 R&D Projects: GA ČR GAP201/10/1920 Institutional research plan: CEZ:AV0Z1019905 Keywords : evolution problems * heat equation * Orlitz-Slobodetskii spaces * Orlitz-Sobolev spaces Subject RIV: BA - General Mathematics Impact factor: 0.631, year: 2015 http://link.springer.com/article/10.1007%2Fs13163-014-0164-4

  20. Communal heating statistics for seven selected sites. Heating energy consumption, heating cost, and carbon dioxide emissions of domestic buildings with central heating systems. Final report; Kommunale Heizspiegel fuer sieben ausgewaehlte Standorte. Heizenergieverbrauch, Heizkosten und CO{sub 2}-Emissionen von zentralbeheizten Wohngebaeuden. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Bade, M. [comp.

    1999-10-01

    Heating staticstics help to define potential energy savings, informing building owners, landlords and tenants on specific energy consumption and specific heating cost of centrally heated multiple dwellings and enabling them a comparison with other buildings of a community. Data are evaluated separately for natural gas, heating oil and district heat. Statistics are presented for the cities of Kiel, Hamburg, Dortmund, Naumburg, Dresden, Wiesbaden and Esslingen. The heating statistics were established in cooperation with heat metering and billing services and building societies in order to obtain a wide data base. [German] Heizpiegel koennen ein wirksames Instrument zur Ausschoepfung des vorhandenen Energiesparpotentials im Gebaeudebestand sein. Sie informieren Gebaeudeeigentuemer, Vermieter und Mieter ueber den spezifischen Heizenergieverbrauch und die spezifischen Heizkosten von zentralbeheizten Mehrfamiliengebaeuden und ermoeglichen gleichzeitig einen Vergleich mit dem uebrigen Gebaeudebestand einer Kommune bzw. Stadt. Die zur Erstellung von Heizspiegeln erforderliche Datenauswertung erfolgt getrennt nach den Energietraegern Erdgas, Heizoel und Fernwaerme. Im Rahmen des Projektes wurden fuer die Staedte Kiel, Hamburg, Dortmund, Naumburg, Dresden, Wiesbaden und Esslingen Heizspiegel erstellt. Bei der Erstellung der Heizspiegel konnte durch die Mitarbeit mehrerer Heizkosten-Verteilerfirmen und Wohnungsgesellschaften auf eine relativ breite Datenbasis zurueckgegriffen werden. (orig.)

  1. Microwave processing heats up

    Science.gov (United States)

    Microwaves are a common appliance in many households. In the United States microwave heating is the third most popular domestic heating method food foods. Microwave heating is also a commercial food processing technology that has been applied for cooking, drying, and tempering foods. It's use in ...

  2. Domestic Violence - Multiple Languages

    Science.gov (United States)

    ... Are Here: Home → Multiple Languages → All Health Topics → Domestic Violence URL of this page: https://medlineplus.gov/languages/ ... V W XYZ List of All Topics All Domestic Violence - Multiple Languages To use the sharing features on ...

  3. International Space Station Common Cabin Air Assembly Condensing Heat Exchanger Hydrophilic Coating Operation, Recovery, and Lessons Learned

    Science.gov (United States)

    Balistreri, Steven F.; Steele, John W.; Caron, Mark E.; Laliberte, Yvon J.; Shaw, Laura A.

    2013-01-01

    The ability to control the temperature and humidity of an environment or habitat is critical for human survival. These factors are important to maintaining human health and comfort, as well as maintaining mechanical and electrical equipment in good working order to support the human and to accomplish mission objectives. The temperature and humidity of the International Space Station (ISS) United States On-orbit Segment (USOS) cabin air is controlled by the Common Cabin Air Assembly (CCAA). The CCAA consists of a fan, a condensing heat exchanger (CHX), an air/water separator, temperature and liquid sensors, and electrical controlling hardware and software. The CHX is the primary component responsible for control of temperature and humidity. The CCAA CHX contains a chemical coating that was developed to be hydrophilic and thus attract water from the humid influent air. This attraction forms the basis for water removal and therefore cabin humidity control. However, there have been several instances of CHX coatings becoming hydrophobic and repelling water. When this behavior is observed in an operational CHX in the ISS segments, the unit s ability to remove moisture from the air is compromised and the result is liquid water carryover into downstream ducting and systems. This water carryover can have detrimental effects on the ISS cabin atmosphere quality and on the health of downstream hardware. If the water carryover is severe and widespread, this behavior can result in an inability to maintain humidity levels in the USOS. This paper will describe the operation of the five CCAAs within the USOS, the potential causes of the hydrophobic condition, and the impacts of the resulting water carryover to downstream systems. It will describe the history of this behavior and the actual observed impacts to the ISS USOS. Information on mitigation steps to protect the health of future CHX hydrophilic coatings as well as remediation and recovery of the full heat exchanger will be

  4. A new geothermal source for spa and space heating in Lavey-les-Bains; Operation geothermique de Lavey-les Bains (VD). CESLA - Chaleur des Eaux Souterraines de Lavey S.A. Realisation du forage geothermique profond P600 et exploitation de la ressource energetique par pompage dans les puits P600 et P201 (juin 1997 - decembre 2002)

    Energy Technology Data Exchange (ETDEWEB)

    Bianchetti, G.

    2002-07-01

    This report presents the construction and the operating performance of a newly drilled borehole in Lavey-les-Bains in Switzerland, which is used to extract high-temperature geothermal water. Associated with an older geothermal source, this well delivering water at the temperature of 68 {sup o}C meets 95% of the heat demand of the Lavey medical and thermal centre, without any heat pump. The heat is used for space heating, ventilation and domestic hot water preparation as well as for the pools. The flow rate from this 517 meter deep well is typically 1,100 liters per minute. The report also describes in details the drilling process as well as the various measurements performed during this period of time. Plenty of figures and schematics are given concerning the technical characteristics of the well and its exploitation procedure. The author suggests the introduction of heat recovery, as water is rejected at a temperature of at least 30 {sup o}C.

  5. Use of buried collector heat pumps in space heating and cooling; Utilisation en chauffage et en refraichissement des thermopompes a capteurs enterres

    Energy Technology Data Exchange (ETDEWEB)

    Bernier, J [Societe SYREC, 22 - Dinan (France)

    1998-12-31

    This paper presents a comparative evaluation of the seasonal thermal performances of the different types of heat pumps with buried collectors: ground/ground type, water-glycol water type, and ground/water type. The different systems are also compared with respect to their adaptation to reversibility. A heat pump system for sanitary hot water production is also presented. (J.S.)

  6. Energy density and storage capacity cost comparison of conceptual solid and liquid sorption seasonal heat storage systems for low-temperature space heating

    NARCIS (Netherlands)

    Scapino, L.; Zondag, H.A.; Van Bael, J.; Diriken, J.; Rindt, C.C.M.

    Sorption heat storage can potentially store thermal energy for long time periods with a higher energy density compared to conventional storage technologies. A performance comparison in terms of energy density and storage capacity costs of different sorption system concepts used for seasonal heat

  7. Use of buried collector heat pumps in space heating and cooling; Utilisation en chauffage et en refraichissement des thermopompes a capteurs enterres

    Energy Technology Data Exchange (ETDEWEB)

    Bernier, J. [Societe SYREC, 22 - Dinan (France)

    1997-12-31

    This paper presents a comparative evaluation of the seasonal thermal performances of the different types of heat pumps with buried collectors: ground/ground type, water-glycol water type, and ground/water type. The different systems are also compared with respect to their adaptation to reversibility. A heat pump system for sanitary hot water production is also presented. (J.S.)

  8. Space heating with ultra-low-temperature district heating - A case study of four single-family houses from the 1980s

    DEFF Research Database (Denmark)

    Østergaard, Dorte Skaarup; Svendsen, Svend

    . These benefits can be maximized if district heating temperatures are lowered as much as possible. In this paper we report on a project where 18 Danish single-family houses from the 1980s were supplied by ultra-low-temperature district heating with a supply temperature as low as 45 °C for the main part...... the four houses were modelled in the building simulation tool IDA ICE. The simulation models included the actual radiator sizes and the models were used to simulate the expected thermal comfort in the houses and resulting district heating return temperatures. Secondly measurements of the actual district...... heating return temperatures in the houses were analysed for different times of the year. The study found that existing Danish single-family houses from the 1980s can be heated with supply temperatures as low as 45 °C for the main part of the year. Both simulation models and test measurements showed...

  9. Solar heating and hot water system installed at Southeast of Saline, Unified School District 306, Mentor, Kansas

    Science.gov (United States)

    1979-01-01

    The solar system, installed in a new building, was designed to provide 52 percent of the estimated annual space heating load and 84 percent of the estimated annual potable hot water requirement. The liquid flat plate collectors are ground-mounted and cover a total area of 5125 square feet. The system will provide supplemental heat for the school's closed-loop water-to-air heat pump system and domestic hot water. The storage medium is water inside steel tanks with a capacity of 11,828 gallons for space heating and 1,600 gallons for domestic hot water. The solar heating facility is described and drawings are presented of the completed system which was declared operational in September 1978, and has functioned successfully since.

  10. 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.

  11. Simulation and optimization study on a solar space heating system combined with a low temperature ASHP for single family rural residential houses in Beijing

    DEFF Research Database (Denmark)

    Deng, Jie; Tian, Zhiyong; Fan, Jianhua

    2016-01-01

    A pilot project of the solar water heating system combined with a low temperature air source heat pump (ASHP) unit was established in 2014 in a detached residential house in the rural region of Beijing, in order to investigate the system application prospect for single family houses via system...... optimization design and economic analysis. The established system was comprised of the glass heat-pipe based evacuated tube solar collectors with a gross area of 18.8 m2 and an ASHP with a stated heating power of 8 kW for the space heating of a single family rural house of 81.4 m2. The dynamic thermal...... with good building insulation were undertaken to figure out the system economical efficiency in the rural regions of Beijing. The results show that the payback periods of the solar space heating system combined with the ASHP with the collector areas 15.04-22.56 m2 are 17.3-22.4 years for the established...

  12. Experimental Study and Modeling of Ground-Source Heat Pumps with Combi-Storage in Buildings

    Directory of Open Access Journals (Sweden)

    Wessam El-Baz

    2018-05-01

    Full Text Available There is a continuous growth of heat pump installations in residential buildings in Germany. The heat pumps are not only used for space heating and domestic hot water consumption but also to offer flexibility to the grid. The high coefficient of performance and the low cost of heat storages made the heat pumps one of the optimal candidates for the power to heat applications. Thus, several questions are raised about the optimal integration and control of heat pump system with buffer storages to maximize its operation efficiency and minimize the operation costs. In this paper, an experimental investigation is performed to study the performance of a ground source heat pump (GSHP with a combi-storage under several configurations and control factors. The experiments were performed on an innovative modular testbed that is capable of emulating a ground source to provide the heat pump with different temperature levels at different times of the day. Moreover, it can emulate the different building loads such as the space heating load and the domestic hot water consumption in real-time. The data gathered from the testbed and different experimental studies were used to develop a simulation model based on Modelica that can accurately simulate the dynamics of a GSHP in a building. The model was validated based on different metrics. Energetically, the difference between the developed model and the measured values was only 3% and 4% for the heat generation and electricity consumption, respectively.

  13. Solar-energy heats a transportation test center--Pueblo, Colorado

    Science.gov (United States)

    1981-01-01

    Petroleum-base, thermal energy transport fluid circulating through 583 square feet of flat-plate solar collectors accumulates majority of energy for space heating and domestic hot-water of large Test Center. Report describes operation, maintenance, and performance of system which is suitable for warehouses and similar buildings. For test period from February 1979 to January 1980, solar-heating fraction was 31 percent, solar hot-water fraction 79 percent.

  14. Space Launch System Base Heating Test: Sub-Scale Rocket Engine/Motor Design, Development and Performance Analysis

    Science.gov (United States)

    Mehta, Manish; Seaford, Mark; Kovarik, Brian; Dufrene, Aaron; Solly, Nathan; Kirchner, Robert; Engel, Carl D.

    2014-01-01

    The Space Launch System (SLS) base heating test is broken down into two test programs: (1) Pathfinder and (2) Main Test. The Pathfinder Test Program focuses on the design, development, hot-fire test and performance analyses of the 2% sub-scale SLS core-stage and booster element propulsion systems. The core-stage propulsion system is composed of four gaseous oxygen/hydrogen RS-25D model engines and the booster element is composed of two aluminum-based model solid rocket motors (SRMs). The first section of the paper discusses the motivation and test facility specifications for the test program. The second section briefly investigates the internal flow path of the design. The third section briefly shows the performance of the model RS-25D engines and SRMs for the conducted short duration hot-fire tests. Good agreement is observed based on design prediction analysis and test data. This program is a challenging research and development effort that has not been attempted in 40+ years for a NASA vehicle.

  15. Marangoni convection in Casson liquid flow due to an infinite disk with exponential space dependent heat source and cross-diffusion effects

    Science.gov (United States)

    Mahanthesh, B.; Gireesha, B. J.; Shashikumar, N. S.; Hayat, T.; Alsaedi, A.

    2018-06-01

    Present work aims to investigate the features of the exponential space dependent heat source (ESHS) and cross-diffusion effects in Marangoni convective heat mass transfer flow due to an infinite disk. Flow analysis is comprised with magnetohydrodynamics (MHD). The effects of Joule heating, viscous dissipation and solar radiation are also utilized. The thermal and solute field on the disk surface varies in a quadratic manner. The ordinary differential equations have been obtained by utilizing Von Kármán transformations. The resulting problem under consideration is solved numerically via Runge-Kutta-Fehlberg based shooting scheme. The effects of involved pertinent flow parameters are explored by graphical illustrations. Results point out that the ESHS effect dominates thermal dependent heat source effect on thermal boundary layer growth. The concentration and temperature distributions and their associated layer thicknesses are enhanced by Marangoni effect.

  16. EL SISTEMA COMO LUGAR. TRES ESTRATEGIAS DE COLECTIVIZACIÓN DEL ESPACIO DOMÉSTICO CONTEMPORÁNEO / The systems a place. Three collectivization strategies of the contemporary domestic space

    Directory of Open Access Journals (Sweden)

    Fernando Nieto Fernández

    2013-11-01

    Full Text Available RESUMEN El artículo pretende definir un conjunto de estrategias de generación del espacio doméstico colectivo actual, a través del análisis de algunos mecanismos basados en la sistematización de los procesos de proyecto. Para ello se establece una confrontación entre tres investigaciones contemporáneas de hábitat colectivo –Gifu, Plus, Elemental– y sendos ejemplos extraídos de algunos manuales de vivienda colectiva del siglo XX –Klein, Alexander, Habraken–. Las teorías de estos tres autores se basan en una taxonomía espacial doméstica desde tres conceptos de partida –forma, límites, tiempo– que permiten establecer un sistema de parámetros ajeno a un contexto específico –sistema de vacíos, sistema de umbrales, sistema de soportes–. Los ejemplos de vivienda colectiva estudiados redefinen en términos actuales algunas de las ideas planteadas por las teorías de referencia, apuntando una suerte de categorización genérica de especies de espacios de habitación.SUMMARY The article attempts to define a set of strategies of generation for the current collective domestic space, through the analysis of certain mechanisms based on the systematization of the project processes. To this end a confrontation is established between three contemporary research works on the collective habitat: Gifu, Plus and Elemental, and individual examples extracted from some collective housing manuals of the XX century: Klein, Alexander and Habraken. The theories of these three authors are based on a domestic spatial taxonomy from three baseline concepts: form, boundaries and time, which allow the establishment of a system of parameters external to a specific context: system of spaces, system of thresholds and system of supports. The studied examples of collective housing redefine, in current terms, some of the ideas proposed by the benchmark theories, pointing to a kind of generic categorization of types of living space.

  17. Remote control systems for space heating. Product overview 2010 and recommendations - Final report; Fernsteuerungen fuer Raumheizungen. Produktuebersicht 2010 und Empfehlungen - Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Geilinger, E.; Bush, E. [Bush Energie GmbH, Felsberg (Switzerland); Venzin, T. [Hochschule fuer Technik und Wirtschaft (HTW) Chur, Chur (Switzerland); Nipkow, J. [Arena, Zuerich (Switzerland)

    2010-09-15

    Saving space heating energy by remote control: A remote-controlled space heating system allows a person to lower the room temperature in homes that go unoccupied for periods of time to the lowest temperature that's safe to keep the pipes from freezing while they're away. Comfort is guaranteed because the desired room temperature or mode can be activated in time before the guests arrive, via text message, phone or the internet. As most people simply leave unoccupied homes heated, the remote-controlled system saves up to 70% of heating energy when used actively. Market overview and product features: This report presents remote control devices that are currently available on the market. Their advantages and disadvantages are discussed as well as their technical features and function. Most of them are universal remote controls that have various uses, including temperature control. The report also discusses requirements that not all the examined products meet. Some lack an emergency power supply, the possibility for manual control or the ability to check the current temperature of the home from a remote location. Better planning for remote control: The critical issue proved not to be the remote control device itself, but the heating systems. Unfortunately, they often don't provide an option to be extended by remote control. We therefore call on the manufacturers to equip all new heating systems with options for remote control. It would also be helpful and desirable to provide information on the internet or in the technical documentation on how to connect a remote control device and which products are suitable - both for existing and new heating systems. If the system cannot be retrofitted, it should be described whether and how a central remote control with room thermostat can be installed. Improving communication: In this study, remote control and heating suppliers were interviewed as well as planners, installers and users of remote-controlled heating. Their responses

  18. Remote control systems for space heating. Product overview 2010 and recommendations - Final report; Fernsteuerungen fuer Raumheizungen. Produktuebersicht 2010 und Empfehlungen - Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Geilinger, E.; Bush, E. [Bush Energie GmbH, Felsberg (Switzerland); Venzin, T. [Hochschule fuer Technik und Wirtschaft (HTW) Chur, Chur (Switzerland); Nipkow, J. [Arena, Zuerich (Switzerland)

    2010-09-15

    Saving space heating energy by remote control: A remote-controlled space heating system allows a person to lower the room temperature in homes that go unoccupied for periods of time to the lowest temperature that's safe to keep the pipes from freezing while they're away. Comfort is guaranteed because the desired room temperature or mode can be activated in time before the guests arrive, via text message, phone or the internet. As most people simply leave unoccupied homes heated, the remote-controlled system saves up to 70% of heating energy when used actively. Market overview and product features: This report presents remote control devices that are currently available on the market. Their advantages and disadvantages are discussed as well as their technical features and function. Most of them are universal remote controls that have various uses, including temperature control. The report also discusses requirements that not all the examined products meet. Some lack an emergency power supply, the possibility for manual control or the ability to check the current temperature of the home from a remote location. Better planning for remote control: The critical issue proved not to be the remote control device itself, but the heating systems. Unfortunately, they often don't provide an option to be extended by remote control. We therefore call on the manufacturers to equip all new heating systems with options for remote control. It would also be helpful and desirable to provide information on the internet or in the technical documentation on how to connect a remote control device and which products are suitable - both for existing and new heating systems. If the system cannot be retrofitted, it should be described whether and how a central remote control with room thermostat can be installed. Improving communication: In this study, remote control and heating suppliers were interviewed as well as planners, installers and users of remote-controlled heating

  19. Exergy and Energy Analysis of Low Temperature District Heating Network

    DEFF Research Database (Denmark)

    Li, Hongwei; Svendsen, Svend

    is in line with a pilot project that is carrying out in Denmark with network supply/return temperature at 55oC/25 oC. The consumer domestic hot water (DHW) demand is supplied with a special designed district heating (DH) storage tank. The space heating (SH) demand is supplied with a low temperature radiator......Low temperature district heating (LTDH) with reduced network supply and return temperature provides better match of the low quality building thermal demand and the low quality waste heat supply. In this paper, an exemplary LTDH network was designed for 30 low energy demand residential houses, which....... The network thermal and hydraulic conditions were simulated under steady state with an in-house district heating network design and simulation code. Through simulation, the overall system energetic and exergetic efficiencies were calculated and the exergy losses for the major district heating system...

  20. Heat Transfer Enhancement and Thermal Management for Space Applications Employing Femtosecond Laser Processed Metallic Surfaces with Micro/Nanostructures

    Data.gov (United States)

    National Aeronautics and Space Administration — Thermal management is one of the most important challenges in space applications. The success of space exploration and travel is directly tied to how we efficiently...

  1. Quantitative Analysis of the Principal-Agent Problem in Commercial Buildings in the U.S.: Focus on Central Space Heating and Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Blum, Helcio; Sathaye, Jayant

    2010-05-14

    We investigate the existence of the principal-agent (PA) problem in non-government, non-mall commercial buildings in the U.S. in 2003. The analysis concentrates on space heating and cooling energy consumed by centrally installed equipment in order to verify whether a market failure caused by the PA problem might have prevented the installation of energy-efficient devices in non-owner-occupied buildings (efficiency problem) and/or the efficient operation of space-conditioning equipment in these buildings (usage problem). Commercial Buildings Energy Consumption Survey (CBECS) 2003 data for single-owner, single-tenant and multi-tenant occupied buildings were used for conducting this evaluation. These are the building subsets with the appropriate conditions for assessing both the efficiency and the usage problems. Together, these three building types represent 51.9percent of the total floor space of all buildings with space heating and 59.4percent of the total end-use energy consumption of such buildings; similarly, for space cooling, they represent 52.7percent of floor space and 51.6percent of energy consumption. Our statistical analysis shows that there is a usage PA problem. In space heating it applies only to buildings with a small floor area (<_50,000 sq. ft.). We estimate that in 2003 it accounts for additional site energy consumption of 12.3 (+ 10.5 ) TBtu (primary energy consumption of 14.6 [+- 12.4] TBtu), corresponding to 24.0percent (+- 20.5percent) of space heating and 10.2percent (+- 8.7percent) of total site energy consumed in those buildings. In space cooling, however, the analysis shows that the PA market failure affects the complete set of studied buildings. We estimate that it accounts for a higher site energy consumption of 8.3 (+-4.0) TBtu (primary energy consumption of 25.5 [+- 12.2]TBtu), which corresponds to 26.5percent (+- 12.7percent) of space cooling and 2.7percent (+- 1.3percent) of total site energy consumed in those buildings.

  2. Heat of Fusion Storage with High Solar Fraction for Solar Low Energy Buildings

    DEFF Research Database (Denmark)

    Schultz, Jørgen Munthe; Furbo, Simon

    2006-01-01

    to achieve 100% coverage of space heating and domestic hot water in a low energy house in a Danish climate with a solar heating system with 36 m² flat plate solar collector and approximately 10 m³ storage with sodium acetate. A traditional water storage solution aiming at 100% coverage will require a storage...... of the storage to cool down below the melting point without solidification preserving the heat of fusion energy. If the supercooled storage reaches the surrounding temperature no heat loss will take place until the supercooled salt is activated. The investigation shows that this concept makes it possible...

  3. Energy, water and space use by free-living red kangaroos Macropus rufus and domestic sheep Ovis aries in an Australian rangeland.

    Science.gov (United States)

    Munn, A J; Dawson, T J; McLeod, S R; Dennis, T; Maloney, S K

    2013-08-01

    We used doubly labelled water to measure field metabolic rates (FMR) and water turnover rates (WTR) in one of Australia's largest native herbivores, the red kangaroo (Macropus rufus) and one of Australia's dominant livestock species, the wool-breed Merino sheep, under free-living conditions in a typical Australian rangeland. Also, we used GPS technology to examine animal space use, along with the comparisons of urine concentration, diet, diet digestibility, and subsequent grazing pressures. We found smaller space-use patterns than previously reported for kangaroos, which were between 14 and 25 % those of sheep. The FMR of a 25-kg kangaroo was 30 % that of a 45-kg sheep, while WTR was 15 % and both were associated with smaller travel distances, lower salt intakes, and higher urine concentration in kangaroos than sheep. After accounting for differences in dry matter digestibility of food eaten by kangaroos (51 %) and sheep (58 %), the relative grazing pressure of a standard (mature, non-reproductive) 25-kg kangaroo was 35 % that of a 45-kg sheep. Even for animals of the same body mass (35 kg), the relative grazing pressure of the kangaroo was estimated to be only 44 % that of the sheep. After accounting for the energetic costs of wool growth by sheep, the FMRs of our sheep and kangaroos were 2-3 times their expected BMRs, which is typical for mammalian FMR:BMRs generally. Notably, data collected from our free-living animals were practically identical to those from animals confined to a semi-natural enclosure (collected in an earlier study under comparable environmental conditions), supporting the idea that FMRs are relatively constrained within species.

  4. Design feasibility of an intermittent domestic energy store

    Energy Technology Data Exchange (ETDEWEB)

    Tahat, M.A. [Jordan Univ. of Sceince and Technology, Irbid (Jordan). Dept. of Mechanical Engineering; Babus`Haq, R.F.; O`Callaghan, P.W.; Probert, S.D. [Cranfield Univ., Bedford (United Kingdom). Dept. of Applied Energy

    1995-09-01

    In recent years, energy storage has been recognised as a potentially significant means by which primary energy consumption can be reduced in domestic, commercial and industrial processes. An intermittent domestic thermochemical heat pump, with a 5 kW{sub e} electric power output when employed as an energy store, is proposed. Different design options have been considered and their economic feasibilities evaluated. (author)

  5. Geothermal space/water heating for Mammoth Lakes Village, California. Quarterly technical progress report, 13 December 1976-12 March 1977

    Energy Technology Data Exchange (ETDEWEB)

    Sims, A.V.; Racine, W.C.

    1977-01-01

    During the second three months of this feasibility study to determine the technical, economic and environmental feasibility of heating Mammoth Lakes Village, California using geothermal energy, the following work was accomplished. A saturation survey of the number and types of space and water heaters currently in use in the Village was completed. Electric energy and ambient temperature metering equipment was installed. Peak heating demand for Mammoth Lakes was estimated for the years 1985, 1990 and 2000. Buildings were selected which are considered typical of Mammoth Lakes in terms of their heating systems to be used in estimating the cost of installing hydronic heating systems in Mammoth. Block diagrams and an order of magnitude cost comparison were prepared for high-temperature and low-temperature geothermal district heating systems. Models depicting a geothermal district heating system and a geothermal-electric power plant were designed, built and delivered to ERDA in Washington. Local input to the feasibility study was obtained from representatives of the State of California Departments of Transportation and Fish and Game, US Forest Service, and Mono County Planning Department.

  6. Criminal aspects domestic violence

    OpenAIRE

    Smetanová, Kristina

    2013-01-01

    Smetanová, Kristina. Criminal aspects of domestic violence The topic of this thesis is the criminal aspects of domestic violence. The aim of the thesis is to describe this dangerous and complicated social problem and focus on outlining the possibilities of protection under Czech criminal law. The thesis consists of eight chapters. The first chapter explains what the domestic violence is and which sources, types and characters does it have.The second chapter shows who can be the violent person...

  7. Domestic violence : evidence review.

    OpenAIRE

    Westmarland, Nicole; Thorlby, Katie; Wistow, Jane; Gadd, David

    2014-01-01

    While domestic violence is high on the public policy agenda in the UK, successive reviews have highlighted policing problems. A recent HMIC report found domestic violence is not policed at the same level as other offences and identified a catalogue of policing failures that have a long history of recurrence. With domestic violence accounting for around a large proportion of violent crime incidents reported to the police, and the majority of all female homicides (Office for National Statistics...

  8. Physicians and domestic violence

    OpenAIRE

    Joslin, Jonathan

    1994-01-01

    Domestic violence, spouse abuse, and battering all refer to the victimization of a person with whom the abuser has or has had an intimate relationship. Domestic violence may take the form of physical, sexual and psychological abuse, is generally repeated, and often escalates within relationships. Most evidence indicates that domestic violence is predominantly perpetrated by men against women. Some evidence suggests that women are just as likely to use violence against male partners as men are...

  9. Domestic violence against children

    OpenAIRE

    Mihić Biljana D.

    2002-01-01

    In this paper the author is analysing definitions and basic notions related to domestic violence against children, as one of the most serious forms of violence. The special chapter deals with effects of violence against children and causes of domestic violence against them. Also, the author is analysing different forms of social reaction and considering the problem of legal regulation of mandatory reporting domestic violence against children.

  10. De-domestication

    DEFF Research Database (Denmark)

    Gamborg, Christian; Gemmen, Bart; Christiansen, Stine Billeschou

    2010-01-01

    as wild or non-wild and the effect this has on questions about how they should be treated. It also concerns the value of nature, and the kind and degree of nature management considered appropriate. The paper first describes actual de-domestication practices and considers the character of human duties...... to animals in process of de-domestication. Secondly, the paper explores the implications of de-domestication for nature management, focusing on notions of naturalness and wildness. Finally, because the current division of ethical topics, with its dependence upon whether animals and nature are domesticated...

  11. New Approach to Simulation of Heat State of Compartments from Lattice Composite Shells for Space Engineering Products

    Directory of Open Access Journals (Sweden)

    Razin Alexander F.

    2017-01-01

    Full Text Available A new approach to the simulation of the heat state of the compartment of lattice polymer composite materials (PCM, not providing for the use of known commercial software packages, has been proposed. The simulation has been performed using the PCM interstage of the Proton rocket as an example with due account of aerodynamic heating, solar radiation and acting of jets of auxiliary propulsion units. At the first stage of numerical analysis, a problem of unsteady heat conduction in the system “skin-air gap-heat insulation” has been solved. An effect of changing a pressure inside a compartment on thermal conductivity of heat insulation was taken into account. The effective thermal conductivity in gaps was used. An effect of a temperature of equipment on a value of radiant heat flux was also taken into account. At the second stage, the heat state of the system “skin-rib” was analyzed. A mathematical model in the form of a system of nonlinear equations for heat balance of control elements on which a rib and a skin section were partitioned, including an information about a temperature of heat insulation received at the first stage of the simulation, was used.

  12. Application of cooling with solid dissecants in solar heating and heating water systems; Aplicacion de la refrigeracion con desecantes solidos en sistemas solares de calefaccion y agua caliente sanitaria

    Energy Technology Data Exchange (ETDEWEB)

    Carrillo Andres, A.; Cejudo Lopez, J. M.; Dominguez Munoz, F.; Serrano Casares, F.

    2004-07-01

    Solar thermal systems designed for domestic hot water and space heating, must be dimensioned on a larger scale than for purely domestic hot water. In summer, when there are many days when no heating is required, the oversized collector area leads to frequent stagnancy situations. In order to use the excess of collector area in summer, a solar desiccant cooling system can be integrated in the solar thermal system. This paper study such combination, using computer simulations with the program TRNSYS, Klein(2000). (Author)

  13. Thermal Performance of Solar Air Heater Having Absorber Plate with V-Down Discrete Rib Roughness for Space-Heating Applications

    Directory of Open Access Journals (Sweden)

    Rajendra Karwa

    2013-01-01

    Full Text Available The paper presents results of thermal performance analysis of a solar air heater with v-down discrete rib roughness on the air flow side of the absorber plate, which supplies heated air for space heating applications. The air heater operates in a closed loop mode with inlet air at a fixed temperature of 295 K from the conditional space. The ambient temperature varied from 278 K to 288 K corresponding to the winter season of Western Rajasthan, India. The results of the analysis are presented in the form of performance plots, which can be utilized by a designer for calculating desired air flow rate at different ambient temperature and solar insolation values.

  14. Pulsating Heat Pipes, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — An advanced heat transport technology is presented that can enable space nuclear power systems to transfer reactor heat, convert heat into electricity, reject waste...

  15. A model predictive control strategy for the space heating of a smart building including cogeneration of a fuel cell-electrolyzer system

    DEFF Research Database (Denmark)

    Sossan, Fabrizio; Bindner, Henrik W.; Madsen, Henrik

    2014-01-01

    The objective of this paper is to analyze the value of energy replacement in the context of demand response. Energy replacement is dened as the possibility of the consumer to choose the most convenient source for providing space heating to a smart building according to a dynamic electricity price....... In the proposed setup, heat is provided by conventional electric radiators and a combined heat and power generation system, composed by a fuel cell and an electrolyzer. The energy replacement strategy is formulated using model predictive control and mathematical models of the components involved. Simulations show...... that the predictive energy replacement strategy reduces the operating costs of the system and is able to provide a larger amount of regulating power to the grid. In the paper, we also develop a novel dynamic model of a PEM fuel cell suitable for micro-grid applications. The model is realized applying a grey...

  16. A solar combi-system based on a heat exchanger between the collector loop and space-heating loop (IEA task 26 generic system 2). A report of IEA SHC - task 26 solar combisystems

    International Nuclear Information System (INIS)

    Ellehauge, K.

    2002-12-01

    The most common Danish solar combi-system is theoretically investigated in the report. The principle in the system is that in a normal solar hot water system a heat exchanger is added to deliver solar energy from the collector loop directly to the space heating loop. In this way solar energy for space heating is not stored which is expected to decrease the performance. On the other hand the system is relatively inexpensive, which can compensate for a reduced performance. A TRNSYS model of the system is developed and sensitivity analyses of parameters are performed by simulation. The analyses show no major improvements of the system. Special emphasis has been put on investigating the control strategy and to investigate if the thermal mass of radiators of floor could act as buffer for the solar energy delivered to space heating and in this way improve the performance. The analyses show that this is possible and has advantages at larger collector areas. However the improvements are not as large as expected. An economic optimisation gives and optimum solar collector area of approximately 10 m 2 . However the optimum curve is quite flat for areas above 7 m 2 , and collector areas up to 15 m 2 are also feasible. The calculated performacnes have been the basis for comparisons with the other systems modelled in the task 26. The comparison shows that the performance is not among the best, but however probably not as bad as expected. Furthermore the inexpensive design compensates to some extent for the lower performance. Furthermore the material use of the system and the energy used to produce the materials has been estimated. The energy demand is in a range that gives energy pay back times of 1.9-2.5 years. (au)

  17. Heat planning for fossil-fuel-free district heating areas with extensive end-use heat savings: A case study of the Copenhagen district heating area in Denmark

    International Nuclear Information System (INIS)

    Harrestrup, M.; Svendsen, S.

    2014-01-01

    The Danish government plans to make the Danish energy system to be completely free of fossil fuels by 2050 and that by 2035 the energy supply for buildings and electricity should be entirely based on renewable energy sources. To become independent from fossil fuels, it is necessary to reduce the energy consumption of the existing building stock, increase energy efficiency, and convert the present heat supply from fossil fuels to renewable energy sources. District heating is a sustainable way of providing space heating and domestic hot water to buildings in densely populated areas. This paper is a theoretical investigation of the district heating system in the Copenhagen area, in which heat conservation is related to the heat supply in buildings from an economic perspective. Supplying the existing building stock from low-temperature energy resources, e.g. geothermal heat, might lead to oversized heating plants that are too expensive to build in comparison with the potential energy savings in buildings. Long-term strategies for the existing building stock must ensure that costs are minimized and that investments in energy savings and new heating capacity are optimized and carried out at the right time. - Highlights: • We investigate how much heating consumption needs to be reduced in a district heating area. • We examine fossil-fuel-free supply vs. energy conservations in the building stock. • It is slightly cost-beneficial to invest in energy renovation from today for a societal point of view. • It is economically beneficial for district heating companies to invest in energy renovations from today. • The cost per delivered heat unit is lower when energy renovations are carried out from today

  18. VAT on domestic energy

    International Nuclear Information System (INIS)

    Crawford, Ian; Smith, Stephen; Webb, Steven.

    1993-01-01

    This publication traces the background to the imposition of VAT on domestic energy, and considers the current patterns of spending. Results of a simulation of the effects of imposition of 17.5% VAT on domestic fuels are presented, and policy measures to offset the impact on poorer households are considered. (UK)

  19. Energy shift estimation of demand response activation on domestic refrigerators – A field test study

    DEFF Research Database (Denmark)

    Lakshmanan, Venkatachalam; Gudmand-Høyer, Kristian; Marinelli, Mattia

    2014-01-01

    This paper presents a method to estimate the amount of energy that can be shifted during demand response (DR) activation on domestic refrigerator. Though there are many methods for DR activation like load reduction, load shifting and onsite generation, the method under study is load shifting....... Electric heating and cooling equipment like refrigerators, water heaters and space heaters and coolers are preferred for such DR activation because of their energy storing capacity. Accurate estimation of available regulating power and energy shift is important to understand the value of DR activation...... at any time. In this paper a novel method to estimate the available energy shift from domestic refrigerators with only two measurements, namely fridge cool chamber temperature and compressor power consumption is proposed, discussed and evaluated....

  20. Heat and fluid flow properties of circular impinging jet with a low nozzle to plate spacing. Improvement by nothched nozzle; Nozzle heibankan kyori ga chiisai baai no enkei shototsu funryu no ryudo dennetsu tokusei. Kirikaki nozzle ni yoru kaizen kojo

    Energy Technology Data Exchange (ETDEWEB)

    Shakouchih, T. [Mie University, Mie (Japan). Faculty of Engineering; Matsumoto, A.; Watanabe, A.

    2000-10-25

    It is well known that as decreasing the nozzle to plate spacing considerably the heat transfer coefficient of circular impinging jet, which impinges to the plate normally, increases remarkably. At that time, the flow resistance of nozzle-plate system also increases rapidly. In this study, in order to reduce the flow resistance and to enhance the heat transfer coefficient of the circular impinging jet with a considerably low nozzle to plate spacing, a special nozzle with notches is proposed, and considerable improvement of the flow and heat transfer properties are shown. The mechanism of enhancement of the heat transfer properties is also discussed. (author)