WorldWideScience

Sample records for heat source safety

  1. Safety Test Program Summary SNAP 19 Pioneer Heat Source Safety Program

    Energy Technology Data Exchange (ETDEWEB)

    None,

    1971-07-01

    Sixteen heat source assemblies have been tested in support of the SNAP 19 Pioneer Safety Test Program. Seven were subjected to simulated reentry heating in various plasma arc facilities followed by impact on earth or granite. Six assemblies were tested under abort accident conditions of overpressure, shrapnel impact, and solid and liquid propellant fires. Three capsules were hot impacted under Transit capsule impact conditions to verify comparability of test results between the two similar capsule designs, thus utilizing both Pioneer and Transit Safety Test results to support the Safety Analysis Report for Pioneer. The tests have shown the fuel is contained under all nominal accident environments with the exception of minor capsule cracks under severe impact and solid fire environments. No catastrophic capsule failures occurred in this test which would release large quantities of fuel. In no test was fuel visible to the eye following impact or fire. Breached capsules were defined as those which exhibit thoria contamination on its surface following a test, or one which exhibited visible cracks in the post test metallographic analyses.

  2. 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

  3. General-purpose heat source safety verification test series: SVT-11 through SVT-13

    International Nuclear Information System (INIS)

    George, T.G.; Pavone, D.

    1986-05-01

    The General-Purpose Heat Source (GPHS) is a modular component of the radioisotope thermoelectric generator that will provide power for the Galileo and Ulysses (formerly ISPM) space missions. The GPHS provides power by transmitting the heat of 238 Pu α-decay to an array of thermoelectric elements. Because the possibility of an orbital abort always exists, the heat source was designed and constructed to minimize plutonia release in any accident environment. The Safety Verification Test (SVT) series was formulated to evaluate the effectiveness of GPHS plutonia containment after atmospheric reentry and Earth impact. The first two reports (covering SVT-1 through SVT-10) described the results of flat, side-on, and angular module impacts against steel targets at 54 m/s. This report describes flat-on module impacts against concrete and granite targets, at velocities equivalent to or higher than previous SVTs

  4. 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

  5. Environmental assessment of general-purpose heat source safety verification testing

    International Nuclear Information System (INIS)

    1995-02-01

    This Environmental Assessment (EA) was prepared to identify and evaluate potential environmental, safety, and health impacts associated with the Proposed Action to test General-Purpose Heat Source (GPHS) Radioisotope Thermoelectric Generator (RTG) assemblies at the Sandia National Laboratories (SNL) 10,000-Foot Sled Track Facility, Albuquerque, New Mexico. RTGs are used to provide a reliable source of electrical power on board some spacecraft when solar power is inadequate during long duration space missions. These units are designed to convert heat from the natural decay of radioisotope fuel into electrical power. Impact test data are required to support DOE's mission to provide radioisotope power systems to NASA and other user agencies. The proposed tests will expand the available safety database regarding RTG performance under postulated accident conditions. Direct observations and measurements of GPHS/RTG performance upon impact with hard, unyielding surfaces are required to verify model predictions and to ensure the continual evolution of the RTG designs that perform safely under varied accident environments. The Proposed Action is to conduct impact testing of RTG sections containing GPHS modules with simulated fuel. End-On and Side-On impact test series are planned

  6. Explosion overpressure test series: General-Purpose Heat Source development: Safety Verification Test program

    International Nuclear Information System (INIS)

    Cull, T.A.; George, T.G.; Pavone, D.

    1986-09-01

    The General-Purpose Heat Source (GPHS) is a modular, radioisotope heat source that will be used in radioisotope thermoelectric generators (RTGs) to supply electric power for space missions. The first two uses will be the NASA Galileo and the ESA Ulysses missions. The RTG for these missions will contain 18 GPHS modules, each of which contains four 238 PuO 2 -fueled clads and generates 250 W/sub (t)/. A series of Safety Verification Tests (SVTs) was conducted to assess the ability of the GPHS modules to contain the plutonia in accident environments. Because a launch pad or postlaunch explosion of the Space Transportation System vehicle (space shuttle) is a conceivable accident, the SVT plan included a series of tests that simulated the overpressure exposure the RTG and GPHS modules could experience in such an event. Results of these tests, in which we used depleted UO 2 as a fuel simulant, suggest that exposure to overpressures as high as 15.2 MPa (2200 psi), without subsequent impact, does not result in a release of fuel

  7. General-Purpose Heat Source Safety Verification Test program: Edge-on flyer plate tests

    International Nuclear Information System (INIS)

    George, T.G.

    1987-03-01

    The radioisotope thermoelectric generator (RTG) that will supply power for the Galileo and Ulysses space missions contains 18 General-Purpose Heat Source (GPHS) modules. The GPHS modules provide power by transmitting the heat of 238 Pu α-decay to an array of thermoelectric elements. Each module contains four 238 PuO 2 -fueled clads and generates 250 W(t). Because the possibility of a launch vehicle explosion always exists, and because such an explosion could generate a field of high-energy fragments, the fueled clads within each GPHS module must survive fragment impact. The edge-on flyer plate tests were included in the Safety Verification Test series to provide information on the module/clad response to the impact of high-energy plate fragments. The test results indicate that the edge-on impact of a 3.2-mm-thick, aluminum-alloy (2219-T87) plate traveling at 915 m/s causes the complete release of fuel from capsules contained within a bare GPHS module, and that the threshold velocity sufficient to cause the breach of a bare, simulant-fueled clad impacted by a 3.5-mm-thick, aluminum-alloy (5052-T0) plate is approximately 140 m/s

  8. Safety-analysis report for packaging (SARP) general-purpose heat-source module 750-Watt shipping container

    International Nuclear Information System (INIS)

    Whitney, M.A.; Burgan, C.E.; Blauvelt, R.K.; Zocher, R.W.; Bronisz, S.E.

    1981-01-01

    The SARP includes discussions of structural integrity, thermal resistance, radiation shielding and radiological safety, nuclear criticality safety, and quality control. Extensive tests and evaluations were performed to show that the container will function effectively with respect to all required standards and when subjected to normal transportation conditions and the sequence of four hypothetical accident conditions (free drop, puncture, thermal, and water immersion). In addition, a steady state temperature profile and radiation profile were measured using two heat sources that very closely resemble the GPHS. This gave an excellent representation of the GPHS temperature and radiation profile. A nuclear criticality safety analysis determined that all safety requirements are met

  9. General-Purpose Heat Source development: Safety Verification Test Program. Bullet/fragment test series

    Energy Technology Data Exchange (ETDEWEB)

    George, T.G.; Tate, R.E.; Axler, K.M.

    1985-05-01

    The radioisotope thermoelectric generator (RTG) that will provide power for space missions contains 18 General-Purpose Heat Source (GPHS) modules. Each module contains four /sup 238/PuO/sub 2/-fueled clads and generates 250 W/sub (t)/. Because a launch-pad or post-launch explosion is always possible, we need to determine the ability of GPHS fueled clads within a module to survive fragment impact. The bullet/fragment test series, part of the Safety Verification Test Plan, was designed to provide information on clad response to impact by a compact, high-energy, aluminum-alloy fragment and to establish a threshold value of fragment energy required to breach the iridium cladding. Test results show that a velocity of 555 m/s (1820 ft/s) with an 18-g bullet is at or near the threshold value of fragment velocity that will cause a clad breach. Results also show that an exothermic Ir/Al reaction occurs if aluminum and hot iridium are in contact, a contact that is possible and most damaging to the clad within a narrow velocity range. The observed reactions between the iridium and the aluminum were studied in the laboratory and are reported in the Appendix.

  10. 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

  11. Dual source heat pump

    Science.gov (United States)

    Ecker, Amir L.; Pietsch, Joseph A.

    1982-01-01

    What is disclosed is a heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating the fluid in heat exchange relationship with a refrigerant fluid; at least two refrigerant heat exchangers, one for effecting heat exchange with the fluid and a second for effecting heat exchange between refrigerant and a heat exchange fluid and the ambient air; a compressor for efficiently compressing the refrigerant; at least one throttling valve for throttling liquid refrigerant; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circulating device and heat exchange fluid circuit for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and direction of flow of the refrigerant therethrough for selecting a particular mode of operation. The heat exchange fluid provides energy for defrosting the second heat exchanger when operating in the air source mode and also provides a alternate source of heat.

  12. General-Purpose Heat Source Development: Safety Test Program. Postimpact evaluation, Design Iteration Test 3

    International Nuclear Information System (INIS)

    Schonfeld, F.W.; George, T.G.

    1984-07-01

    The General-Purpose Heat Source(GPHS) provides power for space missions by transmitting the heat of 238 PuO 2 decay to thermoelectric elements. Because of the inevitable return of certain aborted missions, the heat source must be designed and constructed to survive both re-entry and Earth impact. The Design Iteration Test (DIT) series is part of an ongoing test program. In the third test (DIT-3), a full GPHS module was impacted at 58 m/s and 930 0 C. The module impacted the target at an angle of 30 0 to the pole of the large faces. The four capsules used in DIT-3 survived impact with minimal deformation; no internal cracks other than in the regions indicated by Savannah River Plant (SRP) preimpact nondestructive testing were observed in any of the capsules. The 30 0 impact orientation used in DIT-3 was considerably less severe than the flat-on impact utilized in DIT-1 and DIT-2. The four capsules used in DIT-1 survived, while two of the capsules used in DIT-2 breached; a small quantity (approx. = 50 μg) of 238 PuO 2 was released from the capsules breached in the DIT-2 impact. All of the capsules used in DIT-1 and DIT-2 were severely deformed and contained large internal cracks. Postimpact analyses of the DIT-3 test components are described, with emphasis on weld structure and the behavior of defects identified by SRP nondestructive testing

  13. 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

  14. Thulium-170 heat source

    Science.gov (United States)

    Walter, Carl E.; Van Konynenburg, Richard; VanSant, James H.

    1992-01-01

    An isotopic heat source is formed using stacks of thin individual layers of a refractory isotopic fuel, preferably thulium oxide, alternating with layers of a low atomic weight diluent, preferably graphite. The graphite serves several functions: to act as a moderator during neutron irradiation, to minimize bremsstrahlung radiation, and to facilitate heat transfer. The fuel stacks are inserted into a heat block, which is encased in a sealed, insulated and shielded structural container. Heat pipes are inserted in the heat block and contain a working fluid. The heat pipe working fluid transfers heat from the heat block to a heat exchanger for power conversion. Single phase gas pressure controls the flow of the working fluid for maximum heat exchange and to provide passive cooling.

  15. Radioisotopic heat source

    Science.gov (United States)

    Jones, G.J.; Selle, J.E.; Teaney, P.E.

    1975-09-30

    Disclosed is a radioisotopic heat source and method for a long life electrical generator. The source includes plutonium dioxide shards and yttrium or hafnium in a container of tantalum-tungsten-hafnium alloy, all being in a nickel alloy outer container, and subjected to heat treatment of from about 1570$sup 0$F to about 1720$sup 0$F for about one h. (auth)

  16. Protected isotope heat source

    International Nuclear Information System (INIS)

    Burns, R.K.; Shure, L.I.; Katzen, E.D.

    1975-01-01

    A radioactive isotope capsule is disposed in a container (heat shield) which will have a single stable trim attitude when reentering the earth's atmosphere and while falling to earth. The center of gravity of the heat source is located forward of the midpoint between the front face and the rear face of the container. The capsule is insulated from the front face of the container but not from the rear surface of the container. (auth)

  17. Fuel fired heat sources

    Energy Technology Data Exchange (ETDEWEB)

    Ortlinghaus, U

    1977-09-08

    Fuel fired heat sources with a valve-controlled ignition and main burner, whose flame is monitored and whose control valve is closed or opened by a controller according to the control deviation between actual and reference heat source temperature, previously suffered the disadvantage of high consumption of ignition gas. According to the invention this disadvantage is avoided by closing the ignition valve from the controller via a delay unit and having the delay time of the delay unit controlled either by the temperature measured by the sensor or increasing it with increasing deviation of the actual value of pre-temperature from the reference value of the pre-temperature.

  18. Environmental and radiological safety studies. Interaction of 238PuO2 heat sources with terrestrial and aquatic environments. Progress report, July 1-September 30, 1980

    International Nuclear Information System (INIS)

    Waterbury, G.R.

    1981-01-01

    The containers for 238 PuO 2 heat sources in radioisotope thermoelectric generators are designed with large safety factors to ensure that they will withstand reentry from orbit and impact with the earth and safely contain the nuclear fuel until it is recovered. Existing designs have proved more than adequately safe, but the Space and Terrestrial Division of the Department of Energy Office of Advanced Nuclear Systems and Projects continually seeks more information about the heat sources to improve their safety. The work discussed here includes studies of the effects on the heat source of terrestrial and aquatic environments to obtain data for design of even safer systems. The data obtained in several ongoing experiments are presented; these data tables will be updated quarterly. Discussions of experimental details are minimized and largely repetitive in succeeding reports. Compilations of usable data generated in each experiment are emphasized. These compilations include data from environmental chamber experiments that simulate terrestrial conditions, experiments to measure PuO 2 dissolution rates, soil column experiments to measure sorption of plutonium by soils, and several aquatic experiments

  19. New nuclear heat sources for district heating

    International Nuclear Information System (INIS)

    Lerouge, B.

    1975-01-01

    The means by which urban oil heating may be taken over by new energy sources, especially nuclear, are discussed. Several possibilities exist: pressurized water reactors for high powers, and low-temperature swimming-pool-type process-heat reactors for lower powers. Both these cases are discussed [fr

  20. Regenerative heat sources for heating networks

    International Nuclear Information System (INIS)

    Huenges, Ernst; Sperber, Evelyn; Eggers, Jan-Bleicke; Noll, Florian; Kallert, Anna Maria; Reuss, Manfred

    2015-01-01

    The ambitious goal, the German Federal Government has set itself, to reduce the emissions of greenhouse gases by 80% to 95% by the year 2050. As there are currently more than half of German energy consumption for the production of heat is required, big contributions to climate protection can be expected from this area if more renewable heat sources are used. Renewable heat sources such as bioenergy, solar thermal and geothermal energy in particular can be provided as compared to fossil fuels with significantly lower specific CO 2 emissions. Objectives in the heating market and scenarios for the transformation of the heat sector have been elaborated in the BMU Lead Study 2011. The main pillar of this scenario is the reduction of final energy consumption for heat by the energy-efficient renovation of existing buildings and further increasing demands on the energetic quality of new buildings. To cover the remaining energy demand, a focus is on the expansion of heating networks based on renewable energies. [de

  1. Hot Hydrogen Heat Source Development

    Data.gov (United States)

    National Aeronautics and Space Administration — The purpose of this project is to develop a  hot hydrogen heat source that would produce  a high temperature hydrogen flow which would be comparable to that produced...

  2. General purpose heat source task group. Final report

    International Nuclear Information System (INIS)

    1979-01-01

    The results of thermal analyses and impact tests on a modified design of a 238 Pu-fueled general purpose heat source (GPHS) for spacecraft power supplies are presented. This work was performed to establish the safety of a heat source with pyrolytic graphite insulator shells located either inside or outside the graphite impact shell. This safety is dependent on the degree of aerodynamic heating of the heat source during reentry and on the ability of the heat source capsule to withstand impact after reentry. Analysis of wind tunnel and impact test data result in a recommended GPHS design which should meet all temperature and safety requirements. Further wind tunnel tests, drop tests, and impact tests are recommended to verify the safety of this design

  3. Mechanistic facility safety and source term analysis

    International Nuclear Information System (INIS)

    PLYS, M.G.

    1999-01-01

    A PC-based computer program was created for facility safety and source term analysis at Hanford The program has been successfully applied to mechanistic prediction of source terms from chemical reactions in underground storage tanks, hydrogen combustion in double contained receiver tanks, and proccss evaluation including the potential for runaway reactions in spent nuclear fuel processing. Model features include user-defined facility room, flow path geometry, and heat conductors, user-defined non-ideal vapor and aerosol species, pressure- and density-driven gas flows, aerosol transport and deposition, and structure to accommodate facility-specific source terms. Example applications are presented here

  4. Hybrid district heating system with heat supply from nuclear source

    International Nuclear Information System (INIS)

    Havelka, Z.; Petrovsky, I.

    1987-01-01

    Several designs are described of heat supply from large remote power sources (e.g., WWER-1000 nuclear power plants with a 1000 MW turbine) to localities where mainly steam distribution networks have been built but only some or none networks for hot water distribution. The benefits of the designs stem from the fact that they do not require the conversion of the local steam distribution system to a hot water system. They are based on heat supply from the nuclear power plant to the consumer area in hot water of a temperature of 150 degC to 200 degC. Part of the hot water heat will be used for the production of low-pressure steam which will be compressed using heat pumps (steam compressors) to achieve the desired steam distribution network specifications. Water of lower temperature can be used in the hot water network. The hot water feeder forms an automatic pressure safety barrier in heat supply of heating or technological steam from a nuclear installation. (Z.M.). 5 figs., 9 refs

  5. General Purpose Heat Source Simulator

    Science.gov (United States)

    Emrich, Bill

    2008-01-01

    The General Purpose Heat Source (GPHS) simulator project is designed to replicate through the use of electrical heaters, the form, fit, and function of actual GPHS modules which generate heat through the radioactive decay of Pu238. The use of electrically heated modules rather than modules containing Pu238 facilitates the testing of spacecraft subsystems and systems without sacrificing the quantity and quality of the test data gathered. Previous GPHS activities are centered around developing robust heater designs with sizes and weights that closely matched those of actual Pu238 fueled GPHS blocks. These efforts were successful, although their maximum temperature capabilities were limited to around 850 C. New designs are being pursued which also replicate the sizes and weights of actual Pu238 fueled GPHS blocks but will allow operation up to 1100 C.

  6. Nuclear heat sources for cryogenic refrigerator applications

    International Nuclear Information System (INIS)

    Raab, B.; Schock, A.; King, W.G.; Kline, T.; Russo, F.A.

    1975-01-01

    Spacecraft cryogenic refrigerators require thermal inputs on the order of 1000 W. First, the characteristics of solar-electric and radioisotope heat source systems for supplying this thermal input are compared. Then the design of a 238 Pu heat source for this application is described, and equipment for shipping and handling the heat source is discussed. (LCL)

  7. Radiation Safety and Orphan Sources

    International Nuclear Information System (INIS)

    Janzekovic, H.; Krizman, M.

    2006-01-01

    The wide spread use of radioactive and particularly of nuclear materials which started in the last century very quickly also demonstrated negative sides. The external exposure and radiotoxicity of these materials could be easily used in a malevolent act. Due to the fact that these materials could not be detected without special equipment designed for that purpose, severe control over their use in all phases of a life cycle is required. An orphan source is a radioactive source which is not under regulatory control, either because it has never been under regulatory or because it has been abandoned, lost, misplaced, stolen or transferred without proper authorization. In the last ten years a few international conferences were dedicated to the improvement of the safety and security of radioactive sources. Three main tasks are focused, the maintenance of data bases related to events with orphan sources and the publications of such events, the preparation of recommendations and guidelines to national regulatory bodies in order to prevent and detect the events related to orphan sources as well as to develop the response strategies to radiological or nuclear emergency, appraisals of the national strategies of radioactive sources control. Concerning Slovenia, strengthening control over orphan sources in Slovenia started after the adoption of new legislation in 2002. It was carried out through several tasks with the aim to prevent orphan sources, as well as to identify the sources which could be potentially orphan sources. The comprehensive methodology was developed by the Slovenian nuclear safety administration (S.N.S.A.) based on international guidelines as well as on the study of national lesson learned cases. The methodology was developed and used in close cooperation with all parties involved, namely other regulatory authorities, police, customs, agency for radioactive waste management (A.R.A.O.), technical support organisations (T.S.O.), users of source, authorised

  8. Radiation Safety and Orphan Sources

    Energy Technology Data Exchange (ETDEWEB)

    Janzekovic, H.; Krizman, M. [Slovenian Nuclear Safety Administration, Ljubljana (Slovenia)

    2006-07-01

    The wide spread use of radioactive and particularly of nuclear materials which started in the last century very quickly also demonstrated negative sides. The external exposure and radiotoxicity of these materials could be easily used in a malevolent act. Due to the fact that these materials could not be detected without special equipment designed for that purpose, severe control over their use in all phases of a life cycle is required. An orphan source is a radioactive source which is not under regulatory control, either because it has never been under regulatory or because it has been abandoned, lost, misplaced, stolen or transferred without proper authorization. In the last ten years a few international conferences were dedicated to the improvement of the safety and security of radioactive sources. Three main tasks are focused, the maintenance of data bases related to events with orphan sources and the publications of such events, the preparation of recommendations and guidelines to national regulatory bodies in order to prevent and detect the events related to orphan sources as well as to develop the response strategies to radiological or nuclear emergency, appraisals of the national strategies of radioactive sources control. Concerning Slovenia, strengthening control over orphan sources in Slovenia started after the adoption of new legislation in 2002. It was carried out through several tasks with the aim to prevent orphan sources, as well as to identify the sources which could be potentially orphan sources. The comprehensive methodology was developed by the Slovenian nuclear safety administration (S.N.S.A.) based on international guidelines as well as on the study of national lesson learned cases. The methodology was developed and used in close cooperation with all parties involved, namely other regulatory authorities, police, customs, agency for radioactive waste management (A.R.A.O.), technical support organisations (T.S.O.), users of source, authorised

  9. Member for conducting excess heat away from heat sources

    International Nuclear Information System (INIS)

    Cooke-Yarborough, E.H.

    1975-01-01

    Should a radioisotope-powered engine (e.g., a Stirling cycle engine for generating electricity) stop working for any reason, the radioisotope heat source will continue to generate heat. This will result in a rise in temperature which may cause overheating of and possible damage to the engine as well as to the heat source itself. The invention provides a support/location member for conducting excess heat from the heat source and which, in normal operation of the engine, will impede the conduction of heat away from the heat source and so reduce thermal losses. The member is of elongated form and comprises a stack of heat-conductive slugs disposed in a tube and in interspaced relationship along the axis of the tube. The tube supports the slugs in axial alignment. Means are provided for attaching an end one of the slugs to the heat source and means operable on overheating of said end one of the slugs are also provided whereby the slugs are able to move into heat-conducting contact with each other so as to conduct the excess heat away from said heat source. The slugs may be brazed to the tube whereby progressive overheating of the slugs along the stack results in an overheated slug being freed from attachment to the tube so as to allow the overheated slug to move along the stack and engage the next slug in line in heat-conducting contact. (U.S.)

  10. The radiation safety assessment of the heating loop of district heating reactors

    International Nuclear Information System (INIS)

    Liu Yuanzhong

    1993-01-01

    The district heating reactors are used to supply heating to the houses in cities. The concerned problems are whether the radioactive materials reach the heated houses through heating loop, and whether the safety of the dwellers can be ensured. In order to prevent radioactive materials getting into the heated houses, the district heating reactors have three loops, namely, primary loop, intermediate loop, and heating loop. In the paper, the measures of preventing radioactive materials getting into the heating loop are presented, and the possible sources of the radioactivity in the water of the intermediate loop and the heating loop are given. The regulatory aim limit of radioactive concentration in the water of the intermediate loop is put forward, which is 18.5 Bq/l. Assuming that specific radioactivity of the water of contaminated intermediate loop is up to 18.5 Bq/l, the maximum concentration of radionuclides in water of the heating loop is calculated for the normal operation and the accident of district heating reactor. The results show that the maximum possible concentration is 5.7 x 10 -3 Bq/l. The radiation safety assessment of the heating loop is made out. The conclusions are that the district heating reactors do not bring any harmful impact to the dwellers, and the safety of the dwellers can be safeguarded completely

  11. 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

  12. Optimal usage of low temperature heat sources to supply district heating by heat pumps

    DEFF Research Database (Denmark)

    Pieper, Henrik; Ommen, Torben Schmidt; Markussen, Wiebke Brix

    2017-01-01

    This paper presents a theoretical study on the optimal usage of different low temperature heat sources to supply district heating by heat pumps. The study is based on data for the Copenhagen region. The heat sources were prioritized based on the coefficient of performance calculated for each hour...... and the covered demand of each heat source as well as required peak unit capacity. The results showed that heat pumps using different heat sources yield better performance than a heat pump based on a single one. The performance was influenced by the composition of the different heat sources. It was found that 78......% groundwater, 22% seawater and 0% air resulted in highest COP of 3.33 for the given heat demand. Furthermore, the implementation of rule based short term storage made peak units redundant. The variation in base load capacity showed that heat pumps utilizing the analyzed heat sources could perform very...

  13. Diffusion of heat from a finite, rectangular, plane heat source

    International Nuclear Information System (INIS)

    Ferreri, J.C.; Caballero, C.H.

    1985-01-01

    Non-dimensional results for the temperature field originating in a rectangular, finite, plane heat source with infinitesimal thickness are introduced. The source decays in time, zero decay being a particular case. Results are useful for obtaining an aproximation of the maximum temperature of a system holding an internal heat source. The range selected for the parameters is specially useful in the case of a nuclear waste repository. The application to the case of mass diffussion arises from analogy. (Author) [es

  14. Safety and licensing of nuclear heating plants

    International Nuclear Information System (INIS)

    Snell, V.G.; Hilborn, J.W.; Lynch, G.F.; McAuley, S.J.

    1989-09-01

    World attention continues to focus on nuclear district heating, a low-cost energy from a non-polluting fuel. It offers long-term security for countries currently dependent on fossil fuels, and can reduce the burden of fossil fuel transportation on railways and roads. Current initiatives encompass large, centralized heating plants and small plants supplying individual institutions. The former are variants of their power reactor cousins but with enhanced safety features. The latter face the safety and licensing challenges of urban siting and remotely monitored operation, through use of intrinsic safety features such as passive decay heat removal, low stored energy and limited reactivity speed and depth in the control systems. Small heating reactor designs are compared, and the features of the SLOWPOKE Energy System, in the forefront of these designs, are summarized. The challenge of public perception must be met by clearly presenting the characteristics of small heating reactors in terms of scale and transparent safety in design and operation, and by explaining the local benefits

  15. Mapping of potential heat sources for heat pumps for district heating in Denmark

    International Nuclear Information System (INIS)

    Lund, Rasmus; Persson, Urban

    2016-01-01

    The ambitious policy in Denmark on having a 100% renewable energy supply in 2050 requires radical changes to the energy systems to avoid an extensive and unsustainable use of biomass resources. Currently, wind power is being expanded and the increasing supply of electricity is slowly pushing the CHP (combined heat and power) plants out of operation, reducing the energy efficiency of the DH (district heating) supply. Here, large heat pumps for district heating is a frequently mentioned solution as a flexible demand for electricity and an energy efficient heat producer. The idea is to make heat pump use a low temperature waste or ambient heat source, but it has so far been very unclear which heat sources are actually available for this purpose. In this study eight categories of heat sources are analysed for the case of Denmark and included in a detailed spatial analysis where the identified heat sources are put in relation to the district heating areas and the corresponding demands. The analysis shows that potential heat sources are present near almost all district heating areas and that sea water most likely will have to play a substantial role as a heat source in future energy systems in Denmark. - Highlights: • The availability of heat sources for heat pumps in Denmark are mapped and quantified. • A novel methodology for assessment of low temperature industrial excess heat is presented. • There are heat sources available for 99% of district heating networks in Denmark. • The concentration of heat sources is generally bigger around bigger cities than smaller. • Ambient temperature heat sources will be more needed in district heating of big cities.

  16. Biological effects of intracorporeal radioisotope heat sources

    International Nuclear Information System (INIS)

    Gillis, M.F.; Decker, J.R.; Karagianes, M.T.

    1976-01-01

    A surface heat flux of 0.04 watts/cm 2 from a retroperitoneal implant with healthy surface ingrowth of tissue prior to generation of heat is intolerable, producing gross tissue necrosis. Percutaneous cooling of hot implants during the post-operative healing period is a feasible technique, but our current plutonium heat source implant design has been proven of inadequate size and a new design is described. Rough calculations based on tissue conductivity and conductance values suggest that even with this larger device, added heat to proximate tissues may produce long-term changes even though the heat burden may be tolerable over relatively short periods

  17. Design of serially connected district heating heat pumps utilising a geothermal heat source

    DEFF Research Database (Denmark)

    Jensen, Jonas Kjær; Ommen, Torben Schmidt; Markussen, Wiebke Brix

    2017-01-01

    The design of two heat pumps (HP), connected in series, was investigated for operation in the district heating (DH) network of the Greater Copenhagen area, Denmark. The installation was dimensioned to supply 7.2 MW of heat at a temperature of 85 °C. The heat pumps utilise a geothermal heat source...

  18. Advanced radioisotope heat source for Stirling Engines

    International Nuclear Information System (INIS)

    Dobry, T.J.; Walberg, G.

    2001-01-01

    The heat exchanger on a Stirling Engine requires a thermal energy transfer from a heat source to the engine through a very limited area on the heater head circumference. Designing an effective means to assure maximum transfer efficiency is challenging. A single General Purpose Heat Source (GPHS), which has been qualified for space operations, would satisfy thermal requirements for a single Stirling Engine that would produce 55 electrical watts. However, it is not efficient to transfer its thermal energy to the engine heat exchanger from its rectangular geometry. This paper describes a conceptual design of a heat source to improve energy transfer for Stirling Engines that may be deployed to power instrumentation on space missions

  19. Slowpoke - a new Canadian heat source

    International Nuclear Information System (INIS)

    Bancroft, A.R.; Lynch, G.F.; Ohta, M.M.

    1987-07-01

    Atomic Energy of Canada Limited now has a new product, the SLOWPOKE Energy System, that provides low temperature heat suitable for building and process heating. The SLOWPOKE Energy System is sized to deliver up to 10 megawatts of hot water at up to 90 degrees C, appropriate for large buildings and industrial processes. It is designed for operation without the full-time attendance of dedicated staff and, because of its inherent safety, for siting close to users. At less than 2 cents/kWh, the heat is competitive with oil, gas and electricity in most regions of Canada and the world

  20. Regulatory control of radiation sources. Safety guide

    International Nuclear Information System (INIS)

    2004-01-01

    The basic requirements for the protection of persons against exposure to ionizing radiation and for the safety of radiation sources were established in the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (the Basic Safety Standards), jointly sponsored by the Food and Agriculture Organization of the United Nations (FAO), the International Atomic Energy Agency (IAEA), the International Labour Organization (ILO), the OECD Nuclear Energy Agency (OECD/ NEA), the Pan American Health Organization (PAHO) and the World Health Organization (WHO) (the Sponsoring Organizations). The application of the Basic Safety Standards is based on the presumption that national infrastructures are in place to enable governments to discharge their responsibilities for radiation protection and safety. Requirements relating to the legal and governmental infrastructure for the safety of nuclear facilities and sources of ionizing radiation, radiation protection, the safe management of radioactive waste and the safe transport of radioactive material are established in the Safety Requirements on Legal and Governmental Infrastructure for Nuclear, Radiation, Radioactive Waste and Transport Safety, Safety Standards Series No. GS-R-1. This Safety Guide, which is jointly sponsored by the FAO, the IAEA, the International Labour Office, the PAHO and the WHO, gives detailed guidance on the key elements for the organization and operation of a national regulatory infrastructure for radiation safety, with particular reference to the functions of the national regulatory body that are necessary to ensure the implementation of the Basic Safety Standards. The Safety Guide is based technically on material first published in IAEA-TECDOC-10671, which was jointly sponsored by the FAO, the IAEA, the OECD/NEA, the PAHO and the WHO. The requirements established in GS-R-1 have been taken into account. The Safety Guide is oriented towards national

  1. Hoosac tunnel geothermal heat source. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1982-06-10

    The Hoosac Rail Tunnel has been analyzed as a central element in a district heating system for the City of North Adams. The tunnel has been viewed as a collector of the earth's geothermal heat and a seasonal heat storage facility with heat piped to the tunnel in summer from existing facilities at a distance. Heated fluid would be transported in winter from the tunnel to users who would boost the temperature with individual heat pumps. It was concluded the tunnel is a poor source of geothermal heat. The maximum extractable energy is only 2200 million BTU (20000 gallons of oil) at 58/sup 0/F. The tunnel is a poor heat storage facility. The rock conductivity is so high that 75% of the heat injected would escape into the mountain before it could be recaptured for use. A low temperature system, with individual heat pumps for temperature boost could be economically attractive if a low cost fuel (byproduct, solid waste, cogeneration) or a cost effective seasonal heat storage were available.

  2. Characterization and modeling of the heat source

    Energy Technology Data Exchange (ETDEWEB)

    Glickstein, S.S.; Friedman, E.

    1993-10-01

    A description of the input energy source is basic to any numerical modeling formulation designed to predict the outcome of the welding process. The source is fundamental and unique to each joining process. The resultant output of any numerical model will be affected by the initial description of both the magnitude and distribution of the input energy of the heat source. Thus, calculated weld shape, residual stresses, weld distortion, cooling rates, metallurgical structure, material changes due to excessive temperatures and potential weld defects are all influenced by the initial characterization of the heat source. Understandings of both the physics and the mathematical formulation of these sources are essential for describing the input energy distribution. This section provides a brief review of the physical phenomena that influence the input energy distributions and discusses several different models of heat sources that have been used in simulating arc welding, high energy density welding and resistance welding processes. Both simplified and detailed models of the heat source are discussed.

  3. Safety characteristics of small heat producing reactors

    International Nuclear Information System (INIS)

    Seifritz, W.

    1987-10-01

    The primary objectives of protection in nuclear power plants are the possibility to shut the reactor down in case of emergency and keep it subcritical in the long run, the existence of a heat sink for post-decay heat removal in order to avoid overheating, let alone core meltdown, and the containment of radioactivity within the barriers designed for this purpose, thus preventing significant activity release. In principle, these objectives can be met in various ways, namely by active, passive or inherent technical safeguards systems. In practice, a mixture of these approaches is employed in almost all cases. What matters in the end is the assessment of the overall concept, not of some outstanding feature. Inherent characteristics are easier to achieve in small reactors. However, also in this case, inherent safety does not mean absolute safety. If inherent safety characteristics were all encompassing, they would have to include self-healing effects. However, inanimate matter is incapable of such self-organization. Consequently, inherent characteristics in nuclear technology by definition should include the increased use of dissipative processes in the thermal part of the plant. (author)

  4. Fabrication of three 2500-watt (thermal) strontium-90 heat sources

    International Nuclear Information System (INIS)

    DeVore, J.R.; Haff, K.W.; Tompkins, J.A.

    1986-08-01

    Three 2500-watt (thermal) heat sources were fabricated by the Oak Ridge National Laboratory (ORNL) for the purpose of fueling a 500-watt (electric) thermoelectric generator as part of the US Department of Energy's Byproducts Utilization Program (BUP). Each of the sources, which are the largest ever assembled, consist of hot-pressed pellets of 90 Sr fluoride, doubly encapsulated in three Haynes-25 inner capsules and in a Hastelloy-S outer capsule. The total 90 Sr inventory of all three sources is 1.12 million curies. The sources were fabricated at the ORNL Fission Product Development Laboratory (FPDL), which is a facility that is capable of processing multi-megacurie quantities of radioactive materials, chiefly 137 Cs and 90 Sr. The source was tested to determine compliance with all of the IAEA Safety Series No. 33 requirements. The source fabrication, assembly, and testing are described in the presentation

  5. Air-source heat pump carbon footprints: HFC impacts and comparison to other heat sources

    International Nuclear Information System (INIS)

    Johnson, Eric P.

    2011-01-01

    European governments see that heat pumps could reduce carbon emissions in space- and hot-water heating. EU's Renewable Energy Directive designates heat pumps as renewable - eligible for various subsidies - if their carbon footprints are below an implied, average threshold. This threshold omits carbon generated by manufacture and emission of a heat-pump's fluorocarbon refrigerant. It also omits the footprint of the heat pump's hardware. To see if these omissions are significant, this study calculated carbon footprints of representative, residential heat pumps in the UK. Three findings emerged. First, in relation to power generation, which accounts for most of a heat-pump's greenhouse-gas emissions, fluorocarbons add another 20% to the footprint. Second, at UK efficiencies a heat-pump footprint (in kg CO 2 e emitted per kWh delivered) is comparable or higher than footprints of gaseous fuels used in heating. It is lower than the footprint of heating oil and far lower than the footprints of solid fuels. Third, production and disposal of a heat pump's hardware is relatively insignificant, accounting for only 2-3% of the overall heat-pump footprint. Sensitivities to the results were assessed: key factors are footprint of electricity generation, F-gas composition and leak rates and type of wall construction. - Research highlights: → Refrigerant emissions add 20% to a UK air-source heat pump's carbon footprint. → This contribution is so far ignored by regulations. → UK heat pump footprints are comparable to those of gaseous fuels.

  6. Categorization of Radioactive Sources. Safety Guide

    International Nuclear Information System (INIS)

    2009-01-01

    . The IAEA takes seriously the enduring challenge for users and regulators everywhere: that of ensuring a high level of safety in the use of nuclear materials and radiation sources around the world. Their continuing utilization for the benefit of humankind must be managed in a safe manner, and the IAEA safety standards are designed to facilitate the achievement of that goal.

  7. Heat transfer from the moving heat source of arbitrary shape

    International Nuclear Information System (INIS)

    Fomin, Sergei A.

    2000-01-01

    The present research is related to contact melting by a moving heat source of arbitrary shape. Heat conduction in the melting material is governed by 3D differential equation, where the thermal conductivity of the surrounding material is assumed to be strongly temperature dependent. By using the Green's formula, the boundary-value problem is converted to the boundary integral equation. This non-linear equation is solved numerically by interactions utilizing the boundary element method. Different shapes of heat sources are investigated. Since the obtained integral equation is the Fredholm type equation of the first kind and belongs to the family of so-called ill-posed problems, therefore, supplementary computations, that verify the stability of numerical algorithm, are provided. For the special cases associated with thermodrilling technology, some analytical estimations and solutions are obtained. Particularly, if the melting velocity is high (Pe>10), asymptotic solutions are found. In this case the integral equation is significantly reduced, that simplifies the computations. Numerical results are in good agreement with the closed-form solutions available for the elliptical shape of a solid-liquid interface. (author)

  8. Power generation from low-temperature heat source

    Energy Technology Data Exchange (ETDEWEB)

    Lakew, Amlaku Abie

    2012-07-01

    The potential of low-temperature heat sources for power production has been discussed for decades. The diversity and availability of low-temperature heat sources makes it interesting for power production. The thermodynamic power cycle is one of the promising technologies to produce electricity from low-temperature heat sources. There are different working fluids to be used in a thermodynamic power cycle. Working fluid selection is essential for the performance of the power cycle. Over the last years, different working fluid screening criteria have been used. In broad speaking the screening criteria can be grouped as thermodynamic performance, component size requirement, economic performance, safety and environmental impact. Screening of working fluids at different heat source temperatures (80-200 Celsius degrees) using thermodynamic performance (power output and exergy efficiency) and component size (heat exchanger and turbine) is investigated. It is found that the 'best' working fluid depends on the criteria used and heat source temperature level. Transcritical power cycles using carbon dioxide as a working fluid is studied to produce power at 100 Celsius degrees. Carbon dioxide is an environmentally friendly refrigerant. The global warming potential of carbon dioxide is 1. Furthermore, because of its low critical temperature (31 Celsius degrees), carbon dioxide can operate in a transcritical power cycle for lower heat source temperatures. A transcritical configuration avoids the problem of pinching which otherwise would happened in subcritical power cycle. In the process, better temperature matching is achieved and more heat is extracted. Thermodynamic analysis of transcritical cycle is performed; it is found that there is an optimal operating pressure for highest net power output. The pump work is a sizable fraction of the work produced by the turbine. The effect of efficiency deterioration of the pump and the turbine is compared. When the

  9. Improvements in or relating to devices for conducting excess heat away from heat sources

    International Nuclear Information System (INIS)

    Cooke-Yarborough, E.H.

    1976-01-01

    Reference is made to radioisotope powered heat engines. Should such an engine stop working for any reason the radioisotope heat source will continue to generate heat, and this may cause overheating and possible damage to the engine as well as the heat source. A device is described for conducting excess heat from the heat source to a heat sink but which in normal operation of the engine will impede heat conduction and so reduce thermal losses. The device may be used to support and/or locate the heat source. Constructional and operational details are given. (U.K.)

  10. Design and safety aspects of nuclear district heating reactors

    International Nuclear Information System (INIS)

    Brogli, R.; Mathews, D.; Pelloni, S.

    1989-01-01

    Extensive studies on the rationale, the potential and the technology of nuclear district heating have been performed in Switzerland. Beside economics the safety aspects were of primary importance. Due to the high costs to transport heat the heating reactor tend to be small and therefore, minimally staffed and located close to population centers. Stringed safety rules are therefore applying. Gas cooled reactors are well suited as district heating reactors since they have due to their characteristics several inherent features, significant safety margins and a remarkable radioactivity retention potential. Some ways to mitigate the effects of water ingress and graphite corrosion are under investigation. (author). 5 refs, 3 figs

  11. Utilization of low-temperature heat sources for heat and power production

    DEFF Research Database (Denmark)

    Haglind, Fredrik; Elmegaard, Brian

    2014-01-01

    Low-temperature heat sources are available in many applications, ranging from waste heat from marine diesel engines, industries and refrigeration plants to biomass, geothermal and solar heat sources. There is a great potential for enhancing the utilization of these heat sources by novel...

  12. Cost of heat from a seasonal source

    Science.gov (United States)

    Reilly, R. W.; Brown, D. R.; Huber, H. D.

    Results are reported of an investigation to estimate the cost of aquifer thermal energy storage (ATES) from a seasonal heat source. The cost of supplying energy (hot water) from an ATES system is estimated. Three types of loads are investigated: point demands, residential developments, and a multidistrict city. Several technical and economic factors are found to control the economic performance of an ATES system. Costs are found to be prohibitive for systems of small size, long transmission distances, and employing expensive purchased thermal energy. ATES is found to be cost-competitive with oil-fired and electric hot water delivery systems under a broad range of potential situations.

  13. Regulatory Control of Radiation Sources. Safety Guide

    International Nuclear Information System (INIS)

    2009-01-01

    This Safety Guide is intended to assist States in implementing the requirements established in Safety Standards Series No. GS-R-1, Legal and Governmental Infrastructure for Nuclear, Radiation, Radioactive Waste and Transport Safety, for a national regulatory infrastructure to regulate any practice involving radiation sources in medicine, industry, research, agriculture and education. The Safety Guide provides advice on the legislative basis for establishing regulatory bodies, including the effective independence of the regulatory body. It also provides guidance on implementing the functions and activities of regulatory bodies: the development of regulations and guides on radiation safety; implementation of a system for notification and authorization; carrying out regulatory inspections; taking necessary enforcement actions; and investigating accidents and circumstances potentially giving rise to accidents. The various aspects relating to the regulatory control of consumer products are explained, including justification, optimization of exposure, safety assessment and authorization. Guidance is also provided on the organization and staffing of regulatory bodies. Contents: 1. Introduction; 2. Legal framework for a regulatory infrastructure; 3. Principal functions and activities of the regulatory body; 4. Regulatory control of the supply of consumer products; 5. Functions of the regulatory body shared with other governmental agencies; 6. Organization and staffing of the regulatory body; 7. Documentation of the functions and activities of the regulatory body; 8. Support services; 9. Quality management for the regulatory system.

  14. Trends in safety objectives for nuclear district heating plants

    Energy Technology Data Exchange (ETDEWEB)

    Brogli, R [Paul Scherrer Inst., Villigen (Switzerland)

    1997-09-01

    Safety objectives for dedicated nuclear heating plants are strongly influenced on the one hand by what is accepted for electricity nuclear stations, and on the other hand by the requirement that for economical reasons heating reactors have to be located close to population centers. The paper discusses the related trends and comes to the conclusion that on account of the specific technical characteristics of nuclear heating plants adequate safety can be provided even for highly populated sites. (author). 8 refs.

  15. 21 CFR 872.6475 - Heat source for bleaching teeth.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Heat source for bleaching teeth. 872.6475 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6475 Heat source for bleaching teeth. (a) Identification. A heat source for bleaching teeth is an AC-powered device that consists of a...

  16. Optimal Ground Source Heat Pump System Design

    Energy Technology Data Exchange (ETDEWEB)

    Ozbek, Metin [Environ Holdings Inc., Princeton, NJ (United States); Yavuzturk, Cy [Univ. of Hartford, West Hartford, CT (United States); Pinder, George [Univ. of Vermont, Burlington, VT (United States)

    2015-04-01

    Despite the facts that GSHPs first gained popularity as early as the 1940’s and they can achieve 30 to 60 percent in energy savings and carbon emission reductions relative to conventional HVAC systems, the use of geothermal energy in the U.S. has been less than 1 percent of the total energy consumption. The key barriers preventing this technically-mature technology from reaching its full commercial potential have been its high installation cost and limited consumer knowledge and trust in GSHP systems to deliver the technology in a cost-effective manner in the market place. Led by ENVIRON, with support from University Hartford and University of Vermont, the team developed and tested a software-based a decision making tool (‘OptGSHP’) for the least-cost design of ground-source heat pump (‘GSHP’) systems. OptGSHP combines state of the art optimization algorithms with GSHP-specific HVAC and groundwater flow and heat transport simulation. The particular strength of OptGSHP is in integrating heat transport due to groundwater flow into the design, which most of the GSHP designs do not get credit for and therefore are overdesigned.

  17. Safety of radioactive sources in Portugal

    International Nuclear Information System (INIS)

    Ferro de Carvalho, A.

    2001-01-01

    The safety of radioactive sealed sources is assured in Portugal through a control system with a main goal of prevention of lost of control and inappropriate waste. The legal tools of the regulatory system are: authorization to use, keep, transfer or transport; a deposit of money as a guarantee; civil liability insurance; periodical information. The competent authority shall keep a national inventory of sealed sources. About 50% of the new sources authorized in 1999 were to be used in medical brachytherapy and industrial radiography. The radionuclide Ir-192 contributed with 99.6 % to the total amount of activity. The control system implemented in the country appears to be effective for activities over some GBq but quite ineffective for lower activities. It is supposed that the law will be revised in the near future to increase the effectiveness of the sealed source control system. (author)

  18. Ground Source Heat Pump in Heating System with Electronics Monitoring

    Directory of Open Access Journals (Sweden)

    NEAMŢU Ovidiu

    2013-10-01

    Full Text Available The monitoring system is implemented for a ground coupled heat pump in heating/ system. The borehole heat exchangers – which are 150 m long - are filled with a mixture of water and ethilene glycol calledbrine. Metering and monitoring energy consumption is achieved for: heat pump, circulation pumps, additional electrical heating, hot air ventilation systems, control systems with sensors: analog and smart sensors. Instantaneous values are stored in a local computer.

  19. Radioisotopes for heat-source applications

    International Nuclear Information System (INIS)

    Hoisington, J.E.

    1982-01-01

    Potential DOD requirements for noninterruptable power sources could total 1 MW thermal by FY 1990. Of the three isotopes considered, ( 90 Sr, 147 Pm, 238 Pu) 90 Sr is the only one available in sufficient amounts to meet this requirement. To meet the DOD FY 1990 requirements, it would be necessary to undertake 90 Sr recovery operations from spent fuel reprocessing at SRP, Hanford, and the Barnwell Nuclear Fuels Plant (BNFP). 90 Sr recovery from the existing alkaline high level waste (HLW) at Hanford and SRP is not attractive because the isotopic purity of the 90 Sr is below that required for DOD applications. Without reprocessing LWR spent fuel, SRP and Hanford could not supply the demand of 1 MW thermal until FY 1996. Between FY 1983 and FY 1996, SRP and Hanford could supply approximately 0.70 MW of 90 Sr and 0.15 MW of 147 Pm. SRP could supply an additional 0.15 MW from the production and recovery of 238 Pu. Strontium-90 is the most economical of the three heat source radionuclides considered. The 90 Sr unit recovery cost from SRP fresh acid waste would be $180/watt. The BNFP 90 Sr recovery cost would be $130/watt to $235/watt depending on the age and burnup of the LWR spent fuel. Hanford 90 Sr recovery costs form Purex fresh acid waste are unavailable, but they are expected to be comparable to the SRP costs. 147 Pm and 238 Pu are considerably more expensive heat source materials. 147 Pm recovery costs at SRP are estimated to be $450/watt. As with 90 Sr, the Hanford 147 Pm recovery costs are expected to be comparabl to the SRP costs. Production of high assay (93.5%) 238 Pu at SRP from excess 231 Np would cost about $1160/watt, while recovery of low assay (27%) 238 Pu from the waste stream is estimated at $1850/watt

  20. High-heat tank safety issue resolution program plan

    International Nuclear Information System (INIS)

    Wang, O.S.

    1993-12-01

    The purpose of this program plan is to provide a guide for selecting corrective actions that will mitigate and/or remediate the high-heat waste tank safety issue for single-shell tank (SST) 241-C-106. This program plan also outlines the logic for selecting approaches and tasks to mitigate and resolve the high-heat safety issue. The identified safety issue for high-heat tank 241-C-106 involves the potential release of nuclear waste to the environment as the result of heat-induced structural damage to the tank's concrete, if forced cooling is interrupted for extended periods. Currently, forced ventilation with added water to promote thermal conductivity and evaporation cooling is used to cool the waste. At this time, the only viable solution identified to resolve this safety issue is the removal of heat generating waste in the tank. This solution is being aggressively pursued as the permanent solution to this safety issue and also to support the present waste retrieval plan. Tank 241-C-106 has been selected as the first SST for retrieval. The program plan has three parts. The first part establishes program objectives and defines safety issues, drivers, and resolution criteria and strategy. The second part evaluates the high-heat safety issue and its mitigation and remediation methods and alternatives according to resolution logic. The third part identifies major tasks and alternatives for mitigation and resolution of the safety issue. Selected tasks and best-estimate schedules are also summarized in the program plan

  1. Ground-source heat pump barometer

    International Nuclear Information System (INIS)

    Anon.

    2011-01-01

    In Europe the ground-source heat pump market contracted for the second year running by 2.9% between 2009 and 2010. Around 103.000 units were sold in 2010, taking the number of installed units over one million. The 3 European countries with the most sales are Sweden (31953 units, +16%), Germany (25516 units, -13%) and France (12250 units, -21%). The drop in sales is generally due to market contraction on the current recession but some specificities exist: for instance the insufficient training of the installers has led to under-performance and to a bad image of this energy in France. The Swedish and German manufacturers are in a very strong position and are increasing their market share in the main European markets. (A.C.)

  2. Desalination using low grade heat sources

    Science.gov (United States)

    Gude, Veera Gnaneswar

    A new, low temperature, energy-efficient and sustainable desalination system has been developed in this research. This system operates under near-vacuum conditions created by exploiting natural means of gravity and barometric pressure head. The system can be driven by low grade heat sources such as solar energy or waste heat streams. Both theoretical and experimental studies were conducted under this research to evaluate and demonstrate the feasibility of the proposed process. Theoretical studies included thermodynamic analysis and process modeling to evaluate the performance of the process using the following alternate energy sources for driving the process: solar thermal energy, solar photovoltaic/thermal energy, geothermal energy, and process waste heat emissions. Experimental studies included prototype scale demonstration of the process using grid power as well as solar photovoltaic/thermal sources. Finally, the feasibility of the process in reclaiming potable-quality water from the effluent of the city wastewater treatment plant was studied. The following results have been obtained from theoretical analysis and modeling: (1) The proposed process can produce up to 8 L/d of freshwater for 1 m2 area of solar collector and evaporation chamber respectively with a specific energy requirement of 3122 kJ for 1 kg of freshwater production. (2) Photovoltaic/thermal (PV/T) energy can produce up to 200 L/d of freshwater with a 25 m2 PV/T module which meets the electricity needs of 21 kWh/d of a typical household as well. This configuration requires a specific energy of 3122 kJ for 1 kg of freshwater production. (3) 100 kg/hr of geothermal water at 60°C as heat source can produce up to 60 L/d of freshwater with a specific energy requirement of 3078 kJ for 1 kg of freshwater production. (4) Waste heat released from an air conditioning system rated at 3.25 kW cooling, can produce up to 125 L/d of freshwater. This configuration requires an additional energy of 208 kJ/kg of

  3. Heat source model for welding process

    International Nuclear Information System (INIS)

    Doan, D.D.

    2006-10-01

    One of the major industrial stakes of the welding simulation relates to the control of mechanical effects of the process (residual stress, distortions, fatigue strength... ). These effects are directly dependent on the temperature evolutions imposed during the welding process. To model this thermal loading, an original method is proposed instead of the usual methods like equivalent heat source approach or multi-physical approach. This method is based on the estimation of the weld pool shape together with the heat flux crossing the liquid/solid interface, from experimental data measured in the solid part. Its originality consists in solving an inverse Stefan problem specific to the welding process, and it is shown how to estimate the parameters of the weld pool shape. To solve the heat transfer problem, the interface liquid/solid is modeled by a Bezier curve ( 2-D) or a Bezier surface (3-D). This approach is well adapted to a wide diversity of weld pool shapes met for the majority of the current welding processes (TIG, MlG-MAG, Laser, FE, Hybrid). The number of parameters to be estimated is weak enough, according to the cases considered from 2 to 5 in 20 and 7 to 16 in 3D. A sensitivity study leads to specify the location of the sensors, their number and the set of measurements required to a good estimate. The application of the method on test results of welding TIG on thin stainless steel sheets in emerging and not emerging configurations, shows that only one measurement point is enough to estimate the various weld pool shapes in 20, and two points in 3D, whatever the penetration is full or not. In the last part of the work, a methodology is developed for the transient analysis. It is based on the Duvaut's transformation which overpasses the discontinuity of the liquid metal interface and therefore gives a continuous variable for the all spatial domain. Moreover, it allows to work on a fixed mesh grid and the new inverse problem is equivalent to identify a source

  4. Safety of radiation sources in Slovenia

    International Nuclear Information System (INIS)

    Belicic-Kolsek, A.; Sutej, T.

    2001-01-01

    The Republic of Slovenia, a central European country which has been independent since 1991, has about 2 million inhabitants and an area of 20,256 km 2 . The Constitutional Law on Enforcement of the Basic Constitutional Charter on the Autonomy and Independence of the Republic of Slovenia, adopted on 23 June 1991 (Off. Gaz. of the R of Slovenia No. 1/91), provided that all the laws adopted by the Socialist Federal Republic (SFR) of Yugoslavia should remain in force in the Republic of Slovenia pending the adoption of appropriate legislation by the Slovene Parliament. Under the Slovene Constitution, all international treaties ratified by Slovenia constitute an integral part of Slovenia's legislation and can be applied directly. In Slovenia, all regular types of ionizing radiation source are being used for peaceful purposes and are covered by a system for their safe use and control. All radiation sources and radioactive materials are registered and under regulatory control. Inspections are carried out periodically by the Health Inspectorate of the Republic of Slovenia (HIRS) and, in the case of nuclear installations, the Slovene Nuclear Safety Administration (SNSA). Technical checks on radiation sources are carried out periodically by technical support organizations: the Jozef Stefan Institute and the Institute for Occupational Safety (IOS). (author)

  5. HEAT PUMP USING SUBSOIL WATERS AS LOW TEMPERATURE HEAT SOURCE

    Directory of Open Access Journals (Sweden)

    Denysova Alla

    2015-08-01

    Full Text Available One of the basic directions of perfection of heat supply systems is the tendency of transition to the low-temperature heating systems based on application of heat pump installations. We consider heat supply system with heat pump installations using subsoil waters. Numerical simulation of thermal processes in the elements of a single-stage and double-stage heat pump systems has been worked out. Values of depths of wells and their quantity, necessary for effective operation of the offered installations, and values of capacity of electric water pumps for subsoil waters unit are calculated. Capacity of compressor electric drive and coefficient of performance of heat pump for the conditions of the city of Odessa are presented.

  6. Heat transfer analysis of underground U-type heat exchanger of ground source heat pump system.

    Science.gov (United States)

    Pei, Guihong; Zhang, Liyin

    2016-01-01

    Ground source heat pumps is a building energy conservation technique. The underground buried pipe heat exchanging system of a ground source heat pump (GSHP) is the basis for the normal operation of an entire heat pump system. Computational-fluid-dynamics (CFD) numerical simulation software, ANSYS-FLUENT17.0 have been performed the calculations under the working conditions of a continuous and intermittent operation over 7 days on a GSHP with a single-well, single-U and double-U heat exchanger and the impact of single-U and double-U buried heat pipes on the surrounding rock-soil temperature field and the impact of intermittent operation and continuous operation on the outlet water temperature. The influence on the rock-soil temperature is approximately 13 % higher for the double-U heat exchanger than that of the single-U heat exchanger. The extracted energy of the intermittent operation is 36.44 kw·h higher than that of the continuous mode, although the running time is lower than that of continuous mode, over the course of 7 days. The thermal interference loss and quantity of heat exchanged for unit well depths at steady-state condition of 2.5 De, 3 De, 4 De, 4.5 De, 5 De, 5.5 De and 6 De of sidetube spacing are detailed in this work. The simulation results of seven working conditions are compared. It is recommended that the side-tube spacing of double-U underground pipes shall be greater than or equal to five times of outer diameter (borehole diameter: 180 mm).

  7. Supply of Prague with heat from a nuclear heat source

    International Nuclear Information System (INIS)

    Poul, F.

    1976-01-01

    The proposals are discussed of supplying Prague, the Czechoslovak Capital, with nuclear reactor-generated heat energy. The proposals meet the requirements of the general urban plan of development. The first nuclear heating plant is to be sited in the Kojetice locality, in the northern Prague suburb. It will be commissioned by 1984 and 1985. It is estimated that the maximum heat output in form of hot water will be 821 MW. By 1995 the construction of the second nuclear heating plant should be started southeast or east of Prague. The connection of these two nuclear plants to the hot water mains together with other conventional heating plants will secure the heat supply for Prague and its new housing estates and industrial works. (Oy)

  8. High-heat tank safety issue resolution program plan. Revision 2

    International Nuclear Information System (INIS)

    Wang, O.S.

    1994-12-01

    The purpose of this program plan is to provide a guide for selecting corrective actions that will mitigate and/or remediate the high-heat waste tank safety issue for single-shell tank 241-C-106. The heat source of approximately 110,000 Btu/hr is the radioactive decay of the stored waste material (primarily 90 Sr) inadvertently transferred into the tank in the later 1960s. Currently, forced ventilation, with added water to promote thermal conductivity and evaporation cooling, is used for heat removal. The method is very effective and economical. At this time, the only viable solution identified to permanently resolve this safety issue is the removal of heat-generating waste in the tank. This solution is being aggressively pursued as the only remediation method to this safety issue, and tank 241-C-106 has been selected as the first single-shell tank for retrieval. The current cooling method and other alternatives are addressed in this program as means to mitigate this safety issue before retrieval. This program plan has three parts. The first part establishes program objectives and defines safety issue, drivers, and resolution criteria and strategy. The second part evaluates the high-heat safety issue and its mitigation and remediation methods and other alternatives according to resolution logic. The third part identifies major tasks and alternatives for mitigation and resolution of the safety issue. A table of best-estimate schedules for the key tasks is also included in this program plan

  9. 30 CFR 57.4500 - Heat sources.

    Science.gov (United States)

    2010-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Fire Prevention and Control... shall be separated from combustible materials if a fire hazard could be created. ...

  10. 30 CFR 56.4500 - Heat sources.

    Science.gov (United States)

    2010-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Fire Prevention and Control... shall be separated from combustible materials if a fire hazard could be created. ...

  11. Mapping of low temperature heat sources in Denmark

    DEFF Research Database (Denmark)

    Bühler, Fabian; Holm, Fridolin Müller; Huang, Baijia

    2015-01-01

    heat. The total accessible waste heat potential is found to be approximately 266 PJ per year with 58 % of it below 100 °C. In the natural heat category, temperatures below 20 °C originate from ambient air, sea water and shallow geothermal energy, and temperatures up to 100 °C are found for solar...... and deep geothermal energy. The theoretical solar thermal potential alone would be above 500 PJ per year. For the development of advanced thermodynamic cycles for the integration of heat sources in the Danish energy system, several areas of interest are determined. In the maritime transport sector a high......Low temperature heat sources are available in many applications, ranging from waste heat from industrial processes and buildings to geothermal and solar heat sources. Technical advancements, such as heat pumps with novel cycle design and multi-component working fluids, make the utilisation of many...

  12. Experimental study of adsorption chiller driven by variable heat source

    Energy Technology Data Exchange (ETDEWEB)

    Wang, D.C.; Wang, Y.J.; Zhang, J.P.; Tian, X.L. [College of Electromechanical Engineering, Qingdao University, Qingdao 266071 (China); Wu, J.Y. [Institute of Refrigeration and Cryogenics, Shanghai Jiao Tong University, Shanghai 200030 (China)

    2008-05-15

    A silica gel-water adsorption chiller has been developed in recent years and has been applied in an air conditioning system driven by solar energy. The heat source used to drive the adsorption chiller is variable at any moment because the solar radiation intensity or the waste heat from engines varies frequently. An adsorption cooling system may be badly impacted by a variable heat source with temperature variations in a large range. In this work, a silica gel-water adsorption chiller driven by a variable heat source is experimentally studied. The influences of the variable heat source on the performance of the chiller are analyzed, especially for a continuous temperature increase process and a continuous temperature decrease process of the heat source. As an example, the dynamic characteristics of the heat source are also analyzed when solar energy is taken as the heat source of the adsorption chiller. According to the experimental results for the adsorption chiller and the characteristics of the heat source from solar energy, control strategies of the adsorption chiller driven by solar energy are proposed. (author)

  13. Experimental study of adsorption chiller driven by variable heat source

    International Nuclear Information System (INIS)

    Wang, D.C.; Wang, Y.J.; Zhang, J.P.; Tian, X.L.; Wu, J.Y.

    2008-01-01

    A silica gel-water adsorption chiller has been developed in recent years and has been applied in an air conditioning system driven by solar energy. The heat source used to drive the adsorption chiller is variable at any moment because the solar radiation intensity or the waste heat from engines varies frequently. An adsorption cooling system may be badly impacted by a variable heat source with temperature variations in a large range. In this work, a silica gel-water adsorption chiller driven by a variable heat source is experimentally studied. The influences of the variable heat source on the performance of the chiller are analyzed, especially for a continuous temperature increase process and a continuous temperature decrease process of the heat source. As an example, the dynamic characteristics of the heat source are also analyzed when solar energy is taken as the heat source of the adsorption chiller. According to the experimental results for the adsorption chiller and the characteristics of the heat source from solar energy, control strategies of the adsorption chiller driven by solar energy are proposed

  14. The ion source development for neutral injection heating at JAERI

    International Nuclear Information System (INIS)

    Shirakata, H.; Itoh, T.; Kondoh, U.; Matsuda, S.; Ohara, Y.; Ohga, T.; Shibata, T.; Sugawara, T.; Tanaka, S.

    1976-01-01

    The neutral beam research and development effort at JAERI has been mainly concentrated on design, construction and testing of ion sources needed for present and planned heating experiments. Fundamental characteristics of the ion sources developed are described

  15. Nuclear fuel safety studies by laser pulse heating

    International Nuclear Information System (INIS)

    Viswanadham, C.S.; Kumar, Santosh; Dey, G.K.; Kutty, T.R.G.; Khan, K.B.; Kumar, Arun; Jathar, V.P.; Sahoo, K.C.

    2009-01-01

    The behaviour of nuclear fuels under transient heating conditions is vital to nuclear safety. A laser pulse based heating system to simulate the transient heating conditions experienced by the fuel during reactor accidents like LOCA and RIA is under development at BARC, Mumbai. Some of the concepts used in this system are under testing in pilot studies. This paper describes the results of some pilot studies carried out on unirradiated UO 2 specimens by laser pulse heating, followed by metallography and X-ray diffraction measurements. (author)

  16. Effects of Symmetrically Arranged Heat Sources on the Heat Release Performance of Extruded-Type Heat Sinks

    Energy Technology Data Exchange (ETDEWEB)

    Ku, Min Ye [Chonbuk National Univ., Chonju (Korea, Republic of)

    2016-02-15

    In this study we investigated the effects of symmetrically arranged heat sources on the heat release performances of extruded-type heat sinks through experiments and thermal fluid simulations. Also, based on the results we suggested a high-efficiency and cost-effective heat sink for a solar inverter cooling system. In this parametric study, the temperatures between heaters on the base plate and the heat release rates were investigated with respect to the arrangements of heat sources and amounts of heat input. Based on the results we believe that the use of both sides of the heat sink is the preferred method for releasing the heat from the heat source to the ambient environment rather than the use of a single side of the heat sink. Also from the results, it is believed that the symmetric arrangement of the heat sources is recommended to achieve a higher rate of heat transfer. From the results of the thermal fluid simulation, it was possible to confirm the qualitative agreement with the experimental results. Finally, quantitative comparison with respect to mass flow rates, heat inputs, and arrangements of the heat source was also performed.

  17. Heat sources for heat pumps in the energetic and economic comparison

    International Nuclear Information System (INIS)

    Bockelmann, Franziska; Fisch, M. Norbert; Schlosser, Mathias; Peter, Markus

    2016-01-01

    Because of the growing application of heat pumps also the number of potentially usable low-temperature heat sources and corresponding heat exchangers for heat-pump systems present in the market increases. Thereby products like energy fences, high-power piles, ore ice reservoir come into applications without any knowledge ab out their power or the cost-profit ratio. The optimized lay-out of the coupling to the building are however essential conditions in order to reach an energy-efficient and durable operation of the facilities. The research project ''future heat pump'' sponsored by the BMWi is dedicated to the energetic and economic evaluation of heat sources for heat pumps. In this connection a pre-check-tool for the preliminary selection of low-temperature heat sources and connected, suitable heat-exchange systems is developed and their actual status of development presented. The holistic, comparing consideration of the different heat sources and heat-exchanger systems is related among others to the power numbers of the heat pumps, the entry and withdrawal services of the heat-exchangers, and the general performance of the systems. Additionally an estimation of economic and ecologic aspects (investment and operation costs, CO_2 emissions) is made. Aim is the determination of the plausibility of applications and essential boundary conditions of single source systems. For the qualitative comparison in a project-accompanying monitoring different facilities and source systems are measurement-technically comprehended.

  18. Solar-Radiation Heating as a Possible Heat Source for Dehydration of Hydrous Carbonaceous Chondrites

    Science.gov (United States)

    Nakamura, T.; Golabek, G.; Ohtsuka, K.; Matsuoka, M.

    2017-07-01

    We have calculated time-dependent temperature profiles of near surface layers of primitive Near Sun Asteroid (3200) Phaethon and found that solar radiation heating is a possible heat source for dehydration of carbonaceous chondrites.

  19. Heat-source specification 500 watt(e) RTG

    International Nuclear Information System (INIS)

    1983-02-01

    This specification establishes the requirements for a 90 SrF 2 heat source and its fuel capsule for application in a 500 W(e) thermoelectric generator. The specification covers: fuel composition and quantity; the Hastelloy S fuel capsule material and fabrication; and the quality assurance requirements for the assembled heat source

  20. Safety provision during heating of coal downcast shafts with gas heat generators using degassed methane

    Directory of Open Access Journals (Sweden)

    В. Р. Алабьев

    2017-06-01

    Together with heat generators of mixed type the article also describes a working principle of heat generator of indirect action type, which to the fullest extent possible meets requirements of Russian Federation legislation and regulation for application of this heat generators in coal mines conditions. The article has a principal working scheme of heat unit layout using this type of generator. It is shown that after development of corresponding normative documents regulating processes of design, construction and operation of heating units using heaters of indirect action, their application in Russian coal mines will be possible without breaking Safety standards and rules.

  1. Sources for high frequency heating. Performance and limitations

    International Nuclear Information System (INIS)

    Le Gardeur, R.

    1976-01-01

    The various problems encountered in high frequency heating of plasmas can be decomposed into three spheres of action: theoretical development, antenna designing, and utilization of power sources. By classifying heating into three spectral domains, present and future needs are enumerated. Several specific antenna designs are treated. High frequency power sources are reviewed. The actual development of the gyratron is discussed in view of future needs in very high frequency heating of plasmas [fr

  2. A novel design method for ground source heat pump

    Directory of Open Access Journals (Sweden)

    Dong Xing-Jie

    2014-01-01

    Full Text Available This paper proposes a novel design method for ground source heat pump. The ground source heat pump operation is controllable by using several parameters, such as the total meters of buried pipe, the space between wells, the thermal properties of soil, thermal resistance of the well, the initial temperature of soil, and annual dynamic load. By studying the effect of well number and well space, we conclude that with the increase of the well number, the inlet and outlet water temperatures decrease in summer and increase in winter, which enhance the efficiency of ground source heat pump. The well space slightly affects the water temperatures, but it affects the soil temperature to some extent. Also the ground source heat pump operations matching with cooling tower are investigated to achieve the thermal balance. This method greatly facilitates ground source heat pump design.

  3. Efficiency of the heat pump cooperating with various heat sources in monovalent and bivalent systems

    Energy Technology Data Exchange (ETDEWEB)

    Kurpaska, S.; Latala, H. [Krakow Univ. of Agriculture, Krakow (Poland). Inst. of Agricultural Engineering and Computer Science

    2010-07-01

    This paper reported on a study that tested the efficiency of compressor heat pumps cooperating with various types of lower heat sources such as horizontal ground heat exchangers, vertical exchangers and sources operating in the bivalent system. The system for receiving energy consisted of a traditional heating system and liquid-air exchangers. The study identified a strong relationship between the heating efficiency of the analysed systems and temperature inside the structure. The study showed that the bivalent system was fully capable of meeting a heat requirement of about 1 MJ -2.

  4. Safety technology for air-cooled heat exchangers

    International Nuclear Information System (INIS)

    Kawai, Masafumi; Miyamoto, Hitoshi

    2011-01-01

    The air-cooled heat exchanger is a device that enables a large amount of heat exchange (cooling) by utilizing the atmosphere as a stable and infinite heat sink. It is widely used in general industrial plants, and nowadays it is also utilized in nuclear facilities. This type of exchanger is advantageous in that it can be constructed in any location without having to be near the sea or rivers. It can be operated safely if a natural disaster, such as a tsunami or flood, occurs, thus contributing to the safety of the mother facility. IHI's air-cooled heat exchangers are designed to ensure safe operation and withstand a large earthquake or severe atmospheric conditions. This report describes the technologies used to establish these safety features and their performance. (author)

  5. Heat Transfer treatment in computer codes for safety analysis

    International Nuclear Information System (INIS)

    Jerele, A.; Gregoric, M.

    1984-01-01

    Increased number of operating nuclear power plants has stressed importance of nuclear safety evaluation. For this reason, accordingly to regulatory commission request, safety analyses with computer codes are preformed. In this paper part of this thermohydraulic models dealing with wall-to-fluid heat transfer correlations in computer codes TRAC=PF1, RELAP4/MOD5, RELAP5/MOD1 and COBRA-IV is discussed. (author)

  6. Application of Abaqus to analysis of the temperature field in elements heated by moving heat sources

    Directory of Open Access Journals (Sweden)

    W. Piekarska

    2010-10-01

    Full Text Available Numerical analysis of thermal phenomena occurring during laser beam heating is presented in this paper. Numerical models of surface andvolumetric heat sources were presented and the influence of different laser beam heat source power distribution on temperature field wasanalyzed. Temperature field was obtained by a numerical solution the transient heat transfer equation with activity of inner heat sources using finite element method. Temperature distribution analysis in welded joint was performed in the ABAQUS/Standard solver. The DFLUXsubroutine was used for implementation of the movable welding heat source model. Temperature-depended thermophysical properties for steelwere assumed in computer simulations. Temperature distribution in laser beam surface heated and butt welded plates was numericallyestimated.

  7. Performance variations of river water source heat pump system according to heat exchanger capacity variations

    International Nuclear Information System (INIS)

    Park, Seong Ryong; Baik, Young Jin; Lee, Young Soo; Kim, Hee Hwan

    2003-01-01

    The utilization of unused energy is important because it can afford to offer a chance to increase energy efficiency of a heat pump system. One of the promising unused energy sources is river water. It can be used as a heat source in both heating and cooling effectively with its superior features as a secondary working fluids. In this study, the performance of a 5HP heat pump system using river water as a heat source is investigated by both experiment and simulation. According to system simulation results, performance improvement of condenser seems more effective than that of evaporator for better COPH. The serial connection is also preferred among several methods to improve plate type heat exchanger performance. The experimental results show that the hot water of 50∼60 .deg. C can be acquired from water heat source of 5∼9 .deg. C with COPH of 2.7∼3.5

  8. Geothermal energy. Ground source heat pumps

    International Nuclear Information System (INIS)

    2009-01-01

    Geothermal energy can be harnessed in 2 different ways: electricity or heat generation. The combined net electrical geothermal power of the European Union countries reached 719.3 MWe in 2008 (4.8 MW up on 2007) for 868.1 MWe of installed capacity. Gross electrical production contracted slightly in 2008 (down 1% on the 2007 level) and stood at 5809.5 GWh in 2008. Italy has a overwhelming position with a production of 5520.3 GWh. Geothermal heat production concerning aquifers whose temperature is 30-150 C. degrees generally at a depth of 1-3 km is called low- and medium-enthalpy energy. 18 of the 27 EU members use low- and medium-enthalpy energy totaling 2560.0 MWth of installed capacity that yielded 689.2 ktoe in 2008 and 3 countries Hungary, Italy and France totaling 480.3 ktoe. Very low-enthalpy energy concerns the exploitation of shallow geothermal resources using geothermal heat pumps. In 2008, 114452 ground heat pumps were sold in Europe. At the end of 2008, the installed capacity was 8955.4 MWth (16.5% up on 2007 level, it represented 785206 pumps. Over one million ground heat pumps are expected to be operating in 2010 in Europe. (A.C.)

  9. Second Sound for Heat Source Localization

    CERN Document Server

    Vennekate, Hannes; Uhrmacher, Michael; Quadt, Arnulf; Grosse-Knetter, Joern

    2011-01-01

    Defects on the surface of superconducting cavities can limit their accelerating gradient by localized heating. This results in a phase transition to the normal conduction state | a quench. A new application, involving Oscillating Superleak Transducers (OST) to locate such quench inducing heat spots on the surface of the cavities, has been developed by D. Hartill et al. at Cornell University in 2008. The OSTs enable the detection of heat transfer via second sound in super uid helium. This thesis presents new results on the analysis of their signal. Its behavior has been studied for dierent circumstances at setups at the University of Gottingen and at CERN. New approaches for an automated signal processing have been developed. Furthermore, a rst test setup for a single-cell Superconducting Proton Linac (SPL) cavity has been prepared. Recommendations of a better signal retrieving for its operation are presented.

  10. The Closing Wells as Heat Source

    Directory of Open Access Journals (Sweden)

    Gonet Andrzej

    2004-09-01

    Full Text Available The Turaszówka crude oil field is situated within the borders of Krosno town. The oil resources are nearly depleted. Many of the boreholes have already been liquidated. Currently, only 22 boreholes are being exploited. Eight of them are watered and exploiting oil along with the reservoir water.The boreholes were submitted for producing the geothermal energy, because of their location. They are situated within the urban area. The suggested solution allows for gaining the pure energy and also does not require additional expenditure for mining researches connected with closing of the abandoned boreholes of the field.The paper points to the suggestion and preliminary analysis for wells of Turaszówka oil field adaptation for borehole heat exchangers. There is also presentation of using the heat for Complex of Upper Grammar School heating system and the swimming pool which are both placed close to the oil field.

  11. Source effects on impurity and heat transport in a tokamak

    International Nuclear Information System (INIS)

    Bennett, R.B.

    1980-12-01

    A recently developed generalization of neoclassical theory is extended here to study heat flux contributions to impurity transport, as well as the heat fluxes themselves. The theory accounts for the first four source moments, with external drags, which has been studied previously with either fewer moments or restricted to a collisional plasma. Conditions are established for which a momentum source may be used to modify the particle and heat transport. In the course of this work, the particle and heat transport is evaluated for a two species plasma with arbitrary plasma geometry, beta, and collisionality

  12. Performance analysis on solar-water compound source heat pump for radiant floor heating system

    Institute of Scientific and Technical Information of China (English)

    曲世林; 马飞; 仇安兵

    2009-01-01

    A solar-water compound source heat pump for radiant floor heating (SWHP-RFH) experimental system was introduced and analyzed. The SWHP-RFH system mainly consists of 11.44 m2 vacuum tube solar collector,1 000 L water tank assisted 3 kW electrical heater,a water source heat pump,the radiant floor heating system with cross-linked polyethylene (PE-X) of diameter 20 mm,temperature controller and solar testing system. The SWHP-RFH system was tested from December to February during the heating season in Beijing,China under different operation situations. The test parameters include the outdoor air temperature,solar radiation intensity,indoor air temperature,radiation floor average surface temperature,average surface temperature of the building envelope,the inlet and outlet temperatures of solar collector,the temperature of water tank,the heat medium temperatures of heat pump condenser side and evaporator side,and the power consumption includes the water source heat pump system,the solar source heat pump system,the auxiliary heater and the radiant floor heating systems etc. The experimental results were used to calculate the collector efficiency,heat pump dynamic coefficient of performance (COP),total energy consumption and seasonal heating performance during the heating season. The results indicate that the performance of the compound source heat pump system is better than that of the air source heat pump system. Furthermore,some methods are suggested to improve the thermal performance of each component and the whole SWHP-RFH system.

  13. The economics of supplying the supplementary heat in a closed loop water source heat pump system

    International Nuclear Information System (INIS)

    Johnson, R.P.; Bartkus, V.E.; Singh, J.B.

    1993-01-01

    The paper describes the details of a research and demonstration project that will be completed in August 1992 at a healthcare facility in northeastern Pennsylvania. The purpose of the project is to compare the economics of several methods of supplying the supplementary heating in a facility served by a closed loop water source heat pump system. The systems being tested include a storage hot water tank with electric resistance heaters and three air source heat pumps that have the ability to supply the same heat during on-peak hours as well as off-peak hours. The paper compares the projected operating costs of the following: (1) Gas boiler supplying the supplementary heat. (2) Stored hot water supplying the supplementary heat which is generated and stored during off-peak hours using resistance heat on PP ampersand L's offpeak rate. (3) Stored hot water supplying the supplementary heat generated during off-peak hours using the air source heat pumps on PP ampersand L's off-peak rate. (4) Hot water generated by the air source heat pumps supplying the supplementary loop heating on PP ampersand L's general service and time-of-day electric rates. It is generally known in the HVAC industry that a closed loop water source heat pump system can provide one of the most efficient means of space conditioning to a building with high internal gains by transferring the excess heat available in one part of the building to another part of the building where it may be needed for heating. The following flow diagram depicts the relationship of the air source heat pumps with the storage tanks and the building closed water loop

  14. SELECTION OF HEAT SUPPLY SOURCE FOR MOBILE BUILDING STRUCTURE

    OpenAIRE

    T. I. Dolgikh; S. V. Morozov; Yu. P. Orlov; A. B. Reis; A. Yu Yakovlev

    2014-01-01

    The paper proposes a vortex heat generator with energy transformation of the highest  state  of matter motion  into  the  lowest  one  as  a  heat  supply  source  for a mobile object. Energy transformation coefficient indices close or equal to 1 have been obtained as a result of experiments on efficiency of the vortex heat generator. Such results can be explained with the help of the 2nd Bohr quantum postulate. Standard series of certified VTG heat generators has been proposed for heat suppl...

  15. Nuclear heat source design for an advanced HTGR process heat plant

    International Nuclear Information System (INIS)

    McDonald, C.F.; O'Hanlon, T.W.

    1983-01-01

    A high-temperature gas-cooled reactor (HTGR) coupled with a chemical process facility could produce synthetic fuels (i.e., oil, gasoline, aviation fuel, methanol, hydrogen, etc.) in the long term using low-grade carbon sources (e.g., coal, oil shale, etc.). The ultimate high-temperature capability of an advanced HTGR variant is being studied for nuclear process heat. This paper discusses a process heat plant with a 2240-MW(t) nuclear heat source, a reactor outlet temperature of 950 0 C, and a direct reforming process. The nuclear heat source outputs principally hydrogen-rich synthesis gas that can be used as a feedstock for synthetic fuel production. This paper emphasizes the design of the nuclear heat source and discusses the major components and a deployment strategy to realize an advanced HTGR process heat plant concept

  16. Technical specifications for the provision of heat and steam sources for INPP and Visaginas. Final report

    International Nuclear Information System (INIS)

    2003-01-01

    In October 1999, the National Energy Strategy was approved by the Lithuanian Parliament. The National Energy Strategy included the decision to close Unit-1 of INPP before 2005. Later is has been decided to close Unit 2 before the end of 2009 as well. The closure and decommissioning will have heavy impact on the heat supply for the city of Visaginas. Unit 1 and Unit 2 of INPP supplies hot water and steam to INPP for process purposes and for space heating of residential and commercial buildings. When Unit 1 is permanently shut down, reliable heat and steam sources independent of the power plants own heat and steam generation facilities are required for safety reasons in the event of shutdown of the remaining unit for maintenance or in an emergency. These steam and heat sources must be operational before single unit operation is envisaged. Provision of a reliable independent heat and steam source is therefore urgent. After both reactors are shut down permanently, a steam source will be needed at the plant for radioactive waste storage and disposal. INPP and DEA has performed a feasibility study for the provision of a reliable heat source for Ignalina Nuclear Power Plant and Visaginas, and the modernisation of Visaginas district heating system. The objective of this project is to prepare technical specifications for the provision of new heat and steam sources for INPP and Visaginas, and for rehabilitation of the heat transmission pipeline between INPP, the back-up boiler station and Visaginas City. The results of the study are presented in detail in the reports and technical specifications: 1. Transient analysis for Visaginas DH system, 2. Non-destructive testing of boiler stations, pump stations and transmission lines, 3. Conceptual design, 4. Technical specifications, Package 1 to 6. The study has suggested: 1. Construction of new steam boiler station, 2. Construction of new heat only boiler station, 3. Renovation of existing back-up heat only boiler station, 4

  17. Geothermal source heat pump performance for a greenhouse heating system: an experimental study

    Directory of Open Access Journals (Sweden)

    Alexandros Sotirios Anifantis

    2016-09-01

    Full Text Available Greenhouses play a significant function in the modern agriculture economy even if require great amount of energy for heating systems. An interesting solution to alleviate the energy costs and environmental problems may be represented by the use of geothermal energy. The aim of this paper, based on measured experimental data, such as the inside greenhouse temperature and the heat pump performance (input and output temperatures of the working fluid, electric consumption, was the evaluation of the suitability of low enthalpy geothermal heat sources for agricultural needs such as greenhouses heating. The study was carried out at the experimental farm of the University of Bari, where a greenhouse was arranged with a heating system connected to a ground-source heat pump (GSHP, which had to cover the thermal energy request. The experimental results of this survey highlight the capability of the geothermal heat source to ensue thermal conditions suitable for cultivation in greenhouses even if the compressor inside the heat pump have operated continuously in a fluctuating state without ever reaching the steady condition. Probably, to increase the performance of the heat pump and then its coefficient of performance within GSHP systems for heating greenhouses, it is important to analyse and maximise the power conductivity of the greenhouse heating system, before to design an expensive borehole ground exchanger. Nevertheless, according to the experimental data obtained, the GSHP systems are effective, efficient and environmental friendly and may be useful to supply the heating energy demand of greenhouses.

  18. Applications of New Chemical Heat Sources Phase 1

    National Research Council Canada - National Science Library

    Bell, William

    2001-01-01

    Report developed under Small Business Innovative Research (SBIR) contract. This project has examined the application of new chemical heat sources, with emphasis on portable heaters for military field rations...

  19. Transient thermal stress distribution in a circular pipe heated externally with a periodically moving heat source

    International Nuclear Information System (INIS)

    Özışık, Gülşah; Genç, M. Serdar; Yapıcı, Hüseyin

    2012-01-01

    This study presents the effects of periodically moving heat source on a circular steel pipe heated partly from its outer surface under stagnant ambient conditions. While the pipe is heated with this heat source applied on a certain section having a thickness of heat flux, the water flows through it to transfer heat. It is assumed that the flow is a fully-developed laminar flow. The heat source moves along from one end of the outer to the other end with a constant speed and then returns to the first end with the same speed. It is assumed that the heat transfer rate has a constant value, and that the thermo-physical properties of the steel do not change with temperature (elastic analysis). The numerical calculations have been performed individually for a wide range of thermal conductivity of steel and for different thicknesses of heat flux. The moving heat source produces the non-uniform temperature gradient and the non-uniform effective thermal stress, and when it arrives at the ends of the pipe, the temperature and effective thermal stress ratio profiles rise more excessively. The tangential component is more dominant in the effective thermal stress than the radial component. Highlights: ► Moving heat source produces non-uniform temperature gradients and thermal stresses. ► When moving heat source arrives at ends of pipe, temperature gradients rise excessively. ► With increasing of heat flux thickness and thermal conductivity, the temperature gradients reduce. ► Temperature gradients in thermal boundary layers slightly increase. ► Tangential component is more dominant in thermal stress than radial component.

  20. A directly heated electron beam line source

    International Nuclear Information System (INIS)

    Iqbal, M.; Masood, K.; Rafiq, M.; Chaudhry, M.A.

    2002-05-01

    A 140-mm cathode length, Electron Beam Line Source with a high degree of focusing of the beam is constructed. The design principles and basic characteristic considerations for electron beam line source consists of parallel plate electrode geometric array as well as a beam power of 35kW are worked out. The dimensions of the beam at the work site are 1.25xl00mm. The gun is designed basically for the study of evaporation and deposition characteristic of refractory metals for laboratory use. However, it may be equally used for melting and casting of these metals. (author)

  1. Nuclear heat source component design considerations for HTGR process heat reactor plant concept

    International Nuclear Information System (INIS)

    McDonald, C.F.; Kapich, D.; King, J.H.; Venkatesh, M.C.

    1982-05-01

    The coupling of a high-temperature gas-cooled reactor (HTGR) and a chemical process facility has the potential for long-term synthetic fuel production (i.e., oil, gasoline, aviation fuel, hydrogen, etc) using coal as the carbon source. Studies are in progress to exploit the high-temperature capability of an advanced HTGR variant for nuclear process heat. The process heat plant discussed in this paper has a 1170-MW(t) reactor as the heat source and the concept is based on indirect reforming, i.e., the high-temperature nuclear thermal energy is transported [via an intermediate heat exchanger (IHX)] to the externally located process plant by a secondary helium transport loop. Emphasis is placed on design considerations for the major nuclear heat source (NHS) components, and discussions are presented for the reactor core, prestressed concrete reactor vessel (PCRV), rotating machinery, and heat exchangers

  2. Thermodynamic performance analysis of sequential Carnot cycles using heat sources with finite heat capacity

    International Nuclear Information System (INIS)

    Park, Hansaem; Kim, Min Soo

    2014-01-01

    The maximum efficiency of a heat engine is able to be estimated by using a Carnot cycle. Even though, in terms of efficiency, the Carnot cycle performs the role of reference very well, its application is limited to the case of infinite heat reservoirs, which is not that realistic. Moreover, considering that one of the recent key issues is to produce maximum work from low temperature and finite heat sources, which are called renewable energy sources, more advanced theoretical cycles, which can present a new standard, and the research about them are necessary. Therefore, in this paper, a sequential Carnot cycle, where multiple Carnot cycles are connected in parallel, is studied. The cycle adopts a finite heat source, which has a certain initial temperature and heat capacity, and an infinite heat sink, which is assumed to be ambient air. Heat transfer processes in the cycle occur with the temperature difference between a heat reservoir and a cycle. In order to resolve the heat transfer rate in those processes, the product of an overall heat transfer coefficient and a heat transfer area is introduced. Using these conditions, the performance of a sequential Carnot cycle is analytically calculated. Furthermore, as the efforts for enhancing the work of the cycle, the optimization research is also conducted with numerical calculation. - Highlights: • Modified sequential Carnot cycles are proposed for evaluating low grade heat sources. • Performance of sequential Carnot cycles is calculated analytically. • Optimization study for the cycle is conducted with numerical solver. • Maximum work from a heat source under a certain condition is obtained by equations

  3. Energy source completion for geothermal district heating systems

    International Nuclear Information System (INIS)

    Popovski, Kiril

    2000-01-01

    Geothermal district heating systems differs from the others mainly in the part of energy source completion and its connection to the heat distribution systems rather known problem. Even rather known problematic in the countries where geothermal energy is in wide application, new appearances of mistakes are always present due to the fact that necessary literature is difficult to be found. Essentials of the geothermal well completion and connection of geothermal source to the district heating distribution system are summarized in the paper and several examples of geothermal projects in flow are presented. (Author)

  4. Safety and security of radioactive sources in Taiwan

    International Nuclear Information System (INIS)

    Tsay Yeousong; Guan Channan; Cheng Yungfu

    2008-01-01

    In Taiwan, the safety and security of radioactive sources is a high priority issue. Ionizing Radiation Protection Act (IRPA) and correlating regulations had been in place for effective control of the safety and security of radioactive sources since 2003. For increased control of sealed radioactive sources, Atomic Energy Council (AEC) established in March 2004 an online reporting system through the Internet, assisting source owners in reporting their sources every month. To conform to the Code of Conduct on the Safety and Security of Radioactive Sources and the Categorization of radioactive sources, published by the International Atomic Energy Agency (IAEA), AEC has taken the following actions: 1. Established an inventory of Categories 1 and 2 radioactive sources, and implemented the Import/Export Provisions of the Code. 2. Required that each licensee shall control access to Categories 1 and 2 radioactive sources, and AEC will conduct project inspection on Categories 1 and 2 radioactive sources. 3. Using a new radiation warning symbol by ISO for Categories 1 and 2 radioactive sources. The reinforcement of orphaned source control was implemented as early as 1995. All steel mills have installed radiation detectors to scan incoming metal scrap to prevent accidental smelting of radioactive sources. The results of this effort will be discussed in the paper. The above measures are examples for demonstrating AEC's commitment to reinforced control of radioactive sources. AEC will continue to protect public safety and security, ensuring that Taiwan's regulatory system in radiation protection conforms to international standards. (author)

  5. Infant otitis media and the use of secondary heating sources.

    Science.gov (United States)

    Pettigrew, Melinda M; Gent, Janneane F; Triche, Elizabeth W; Belanger, Kathleen D; Bracken, Michael B; Leaderer, Brian P

    2004-01-01

    This prospective study investigated the association of exposure to indoor secondary heating sources with otitis media and recurrent otitis media risk in infants. We enrolled mothers living in nonsmoking households and delivering babies between 1993 and 1996 in 12 Connecticut and Virginia hospitals. Biweekly telephone interviews during the first year of life assessed diagnoses from doctors' office visits and use of secondary home heating sources, air conditioner use, and day care. Otitis media episodes separated by more than 21 days were considered to be unique episodes. Recurrent otitis media was defined as 4 or more episodes of otitis media. Repeated-measures logistic regression modeling evaluated the association of kerosene heater, fireplace, or wood stove use with otitis media episodes while controlling for potential confounders. Logistic regression evaluated the relation of these secondary heating sources with recurrent otitis media. None of the secondary heating sources were associated with otitis media or with recurrent otitis media. Otitis media was associated with day care, the winter heating season, birth in the fall, white race, additional children in the home, and a maternal history of allergies in multivariate models. Recurrent otitis media was associated with day care, birth in the fall, white race, and a maternal history of allergies or asthma. We found no evidence that the intermittent use of secondary home heating sources increases the risk of otitis media or recurrent otitis media. This study confirms earlier findings regarding the importance of day care with respect to otitis media risk.

  6. Interface for safety and security of radioactive sources

    International Nuclear Information System (INIS)

    Seggane, Richard

    2016-04-01

    In facilities and activities involving use of radiation sources, safety and security measures have in common the aim of protecting human life and health and the environment. In addition, safety and security measures must be designed and implemented in an integrated manner, so that security measures do not compromise safety and safety measures do not compromise security measures. This work reviewed issues related to establishing a clear interface between safety and security of radiation sources. The Government, the Regulatory Authority and licensee/registrants and other relevant stakeholders should work together and contribute to ensure that safety and security of sources is ensured and well interfaced. A Radiotherapy facility has been used as a case study. (au)

  7. Research status and evaluation system of heat source evaluation method for central heating

    Science.gov (United States)

    Sun, Yutong; Qi, Junfeng; Cao, Yi

    2018-02-01

    The central heating boiler room is a regional heat source heating center. It is also a kind of the urban environment pollution, it is an important section of building energy efficiency. This article through to the evaluation method of central heating boiler room and overviews of the researches during domestic and overseas, summarized the main influence factors affecting energy consumption of industrial boiler under the condition of stable operation. According to the principle of establishing evaluation index system. We can find that is great significance in energy saving and environmental protection for the content of the evaluation index system of the centralized heating system.

  8. Natural Diversity in Heat Resistance of Bacteria and Bacterial Spores: Impact on Food Safety and Quality.

    Science.gov (United States)

    den Besten, Heidy M W; Wells-Bennik, Marjon H J; Zwietering, Marcel H

    2018-03-25

    Heat treatments are widely used in food processing often with the aim of reducing or eliminating spoilage microorganisms and pathogens in food products. The efficacy of applying heat to control microorganisms is challenged by the natural diversity of microorganisms with respect to their heat robustness. This review gives an overview of the variations in heat resistances of various species and strains, describes modeling approaches to quantify heat robustness, and addresses the relevance and impact of the natural diversity of microorganisms when assessing heat inactivation. This comparison of heat resistances of microorganisms facilitates the evaluation of which (groups of) organisms might be troublesome in a production process in which heat treatment is critical to reducing the microbial contaminants, and also allows fine-tuning of the process parameters. Various sources of microbiological variability are discussed and compared for a range of species, including spore-forming and non-spore-forming pathogens and spoilage organisms. This benchmarking of variability factors gives crucial information about the most important factors that should be included in risk assessments to realistically predict heat inactivation of bacteria and spores as part of the measures for controlling shelf life and safety of food products.

  9. Helium release from radioisotope heat sources

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, D.E.; Early, J.W.; Starzynski, J.S.; Land, C.C.

    1984-05-01

    Diffusion of helium in /sup 238/PuO/sub 2/ fuel was characterized as a function of the heating rate and the fuel microstructure. The samples were thermally ramped in an induction furnace and the helium release rates measured with an automated mass spectrometer. The diffusion constants and activation energies were obtained from the data using a simple diffusion model. The release rates of helium were correlated with the fuel microstructure by metallographic examination of fuel samples. The release mechanism consists of four regimes, which are dependent upon the temperature. Initially, the release is controlled by movement of point defects combined with trapping along grain boundaries. This regime is followed by a process dominated by formation and growth of helium bubbles along grain boundaries. The third regime involves volume diffusion controlled by movement of oxygen vacancies. Finally, the release at the highest temperatures follows the diffusion rate of intragranular bubbles. The tendency for helium to be trapped within the grain boundaries diminishes with small grain sizes, slow thermal pulses, and older fuel.

  10. Helium release from radioisotope heat sources

    International Nuclear Information System (INIS)

    Peterson, D.E.; Early, J.W.; Starzynski, J.S.; Land, C.C.

    1984-05-01

    Diffusion of helium in 238 PuO 2 fuel was characterized as a function of the heating rate and the fuel microstructure. The samples were thermally ramped in an induction furnace and the helium release rates measured with an automated mass spectrometer. The diffusion constants and activation energies were obtained from the data using a simple diffusion model. The release rates of helium were correlated with the fuel microstructure by metallographic examination of fuel samples. The release mechanism consists of four regimes, which are dependent upon the temperature. Initially, the release is controlled by movement of point defects combined with trapping along grain boundaries. This regime is followed by a process dominated by formation and growth of helium bubbles along grain boundaries. The third regime involves volume diffusion controlled by movement of oxygen vacancies. Finally, the release at the highest temperatures follows the diffusion rate of intragranular bubbles. The tendency for helium to be trapped within the grain boundaries diminishes with small grain sizes, slow thermal pulses, and older fuel

  11. Review of Safety and Security of Radioactive Sources in Africa

    International Nuclear Information System (INIS)

    Kiti, Shadrack Anthony; Choi, Kwang Sik

    2011-01-01

    Radioactive materials are used worldwide for peaceful applications in medicine, industry, agriculture, environmental science, education and research and military applications. Most of these radioactive sources used are imported therefore trans-boundary movement is a significant factor in consideration of safety and security measures during movement of these sources. It is estimated that 20 million packages of radioactive materials are transported annually worldwide and this number of shipments is expected to increase due to the renaissance of nuclear power generation. The African continent has shown considerable leadership in its advocacy for the safety and security of radioactive sources. The First Africa Workshop on the Establishment of a Legal Framework governing Radiation Protection, the Safety of Radiation Sources and the Safe Management of Radioactive Waste held in Ethiopia in 2001 called upon the IAEA to form a forum for African countries to consider the Code of Conduct on the Safety and Security of Radioactive Sources and give it a legally binding effect so that the peaceful use of nuclear technology is not compromised. Despite these laudable efforts, Africa still faces considerable challenges in the implementation of safety and security of radioactive sources because of weak regulatory control and lack of infrastructure to properly control, manage and secure radiation sources 1 . The purpose of this paper was therefore, to analyze, review, address and share knowledge and experience with regard to safety and security measures of radioactive materials in Africa. This project will benefit IAEA's African member states in creating nuclear safety and security networking in the region

  12. Welding of iridium heat source capsule components

    International Nuclear Information System (INIS)

    Mustaleski, T.M.; Yearwood, J.C.; Burgan, C.E.; Green, L.A.

    1991-01-01

    Interplanetary spacecraft have long used radioisotope thermoelectric generators (RTG) to produce power for instrumentation. These RTG produce electrical energy from the heat generated through the radioactive decay of plutonium-238. The plutonium is present as a ceramic pellet of plutonium oxide. The pellet is encapsulated in a containment shell of iridium. Iridium is the material of choice for these capsules because of its compatibility with the plutonium dioxide. The high-energy beam welding (electron beam and laser) processes used in the fabrication of the capsules has not been published. These welding procedures were originally developed at the Mound Laboratories and have been adapted for use at the Oak Ridge Y-12 Plant. The work involves joining of thin material in small sizes to exacting tolerances. There are four different electron beam welds on each capsule, with one procedure being used in three locations. There is also a laser weld used to seal the edges of a sintered frit assembly. An additional electron beam weld is also performed to seal each of the iridium blanks in a stainless steel waster sheet prior to forming. In the transfer of these welding procedures from one facility to another, a number of modifications were necessary. These modifications are discussed in detail, as well as the inherent problems in making welds in material which is only 0.005 in. thick. In summary, the paper discusses the welding of thin components of iridium using the high energy beam processes. While the peculiarities of iridium are pertinent to the discussion, much of the information is of general interest to the users of these processes. This is especially true of applications involving thin materials and high-precision assemblies

  13. Ground Source Geothermal District Heating and Cooling System

    Energy Technology Data Exchange (ETDEWEB)

    Lowe, James William [Ball State Univ., Muncie, IN (United States)

    2016-10-21

    Ball State University converted its campus from a coal-fired steam boiler district heating system to a ground source heat pump geothermal district system that produces simultaneously hot water for heating and chilled water for cooling. This system will include the installation of 3,600 four hundred feet deep vertical closed loop boreholes making it the largest ground source geothermal district system in the country. The boreholes will act as heat exchangers and transfer heat by virtue of the earth’s ability to maintain an average temperature of 55 degree Fahrenheit. With growing international concern for global warming and the need to reduce worldwide carbon dioxide loading of the atmosphere geothermal is poised to provide the means to help reduce carbon dioxide emissions. The shift from burning coal to utilizing ground source geothermal will increase electrical consumption but an overall decrease in energy use and reduction in carbon dioxide output will be achieved. This achievement is a result of coupling the ground source geothermal boreholes with large heat pump chiller technology. The system provides the thermodynamic means to move large amounts of energy with limited energy input. Ball State University: http://cms.bsu.edu/About/Geothermal.aspx

  14. Safety regulation for the design approval of special form radioactive sources

    International Nuclear Information System (INIS)

    Cho, Woon-Kap

    2009-01-01

    Several kinds of special form radioactive sources for industrial, medical applications are being produced in Korea. Special form radioactive sources should meet strict safety requirements specified in the domestic safety regulations and the design of the sources should be certified by the regulatory authority, the Ministry of Education, Science and Technology (MEST). Several safety tests such as impact, percussion, heating, and leak tests are performed on the sources according to the domestic regulations and the international safety standards such as ANSI N542-1977 and ISO 2919-1999(E). As a regulatory expert body, Korea Institute of Nuclear Safety (KINS) assesses various types of application documents, such as safety analysis report, quality assurance program, and other documents evidencing fulfillment of requirements for design approval of the special form radioactive sources, submitted by a legal person who intends to produce special form radioactive sources and then reports the assessment result to MEST. A design approval certificate is issued to the applicant by MEST on the basis of a technical evaluation report presented by KINS.

  15. X-ray source safety shutter

    International Nuclear Information System (INIS)

    Robinet, M.

    1977-01-01

    An apparatus is provided for controlling the activation of a high energy radiation source having a shutter. The apparatus includes magnets and magnetically responsive switches appropriately placed and interconnected so that only with the shutter and other parts of the source in proper position can safe emission of radiation out an open shutter occur

  16. A Study on Conjugate Heat Transfer Analysis of Reactor Vessel including Irradiated Structural Heat Source

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Kunwoo; Cho, Hyuksu; Im, Inyoung; Kim, Eunkee [KEPCO EnC, Daejeon (Korea, Republic of)

    2015-10-15

    Though Material reliability programs (MRPs) have a purpose to provide the evaluation or management methodologies for the operating RVI, the similar evaluation methodologies can be applied to the APR1400 fleet in the design stage for the evaluation of neutron irradiation effects. The purposes of this study are: to predict the thermal behavior whether or not irradiated structure heat source; to evaluate effective thermal conductivity (ETC) in relation to isotropic and anisotropic conductivity of porous media for APR1400 Reactor Vessel. The CFD simulations are performed so as to evaluate thermal behavior whether or not irradiated structure heat source and effective thermal conductivity for APR1400 Reactor Vessel. In respective of using irradiated structure heat source, the maximum temperature of fluid and core shroud for isotropic ETC are 325.8 .deg. C, 341.5 .deg. C. The total amount of irradiated structure heat source is about 5.41 MWth and not effect to fluid temperature.

  17. Simulation of embedded heat exchangers of solar aided ground source heat pump system

    Institute of Scientific and Technical Information of China (English)

    王芳; 郑茂余; 邵俊鹏; 李忠建

    2008-01-01

    Aimed at unbalance of soil temperature field of ground source heat pump system, solar aided energy storage system was established. In solar assisted ground-source heat pump (SAGSHP) system with soil storage, solar energy collected in three seasons was stored in the soil by vertical U type soil exchangers. The heat abstracted by the ground-source heat pump and collected by the solar collector was employed to heating. Some of the soil heat exchangers were used to store solar energy in the soil so as to be used in next winter after this heating period; and the others were used to extract cooling energy directly in the soil by circulation pump for air conditioning in summer. After that solar energy began to be stored in the soil and ended before heating period. Three dimensional dynamic numerical simulations were built for soil and soil heat exchanger through finite element method. Simulation was done in different strata month by month. Variation and restoration of soil temperature were studied. Economy and reliability of long term SAGSHP system were revealed. It can be seen that soil temperature is about 3 ℃ higher than the original one after one year’s running. It is beneficial for the system to operate for long period.

  18. Experimental study on local heat transfer characteristics of porous media with internal heat source

    International Nuclear Information System (INIS)

    Zan Yuanfeng; Wang Taotao; Xiao Zejun; Wang Fei; Huang Yanping

    2008-01-01

    Model of porous media with internal heat source is established. The model uses water as flowing media, and the stainless steel test section is packed with steel spheres in manner of regular triangle, respectively. The armoured resistance wire is inserted inside the steel sphere. On the basis of the experimental model, many parameters of the local heat transfer characteristics including current velocity and wall temperature of steel sphere are measured. The experimental results show that the coefficient of heat transfer scarcely changes with pressure. The coefficient of heat transfer increases with the surface heat flux of steel sphere. When raising the inlet temperature of the cooling water, the coefficient of heat transfer presents the descending trend. In addition, the influence of entrance effect on heat transfer is discovered in the experiment, which is much less than the liquid flow in the light tube. After experiment data are analyzed and processed, the relation model of heat transfer on local heat transfer characteristic of porous media with internal heat source was described with a power-law-equation. The deviations between calculation and experimental values are within ±10%. (authors)

  19. Ground Source Heat Supply in Moscow Oblast: Temperature Potential and Sustainable Depth of Heat Wells

    Science.gov (United States)

    Vasil'ev, G. P.; Gornov, V. F.; Dmitriev, A. N.; Kolesova, M. V.; Yurchenko, V. A.

    2018-01-01

    The paper is devoted to a problem of increasing the efficiency of low-potential geothermal heat in heat pump systems of residential buildings the Moscow oblast of Russia, including Moscow. Estimates of a natural geothermal potential in the Moscow oblast (based on climatological data for the period from 1982 to 2011) are presented and a "Typical climatic year of natural soil temperature variations for the geoclimatic conditions of the Moscow oblast, including the city of Moscow" is proposed. Numerical simulation of the influence of geothermal energy potential and the depth of heat wells on the efficiency of ground source heat pump systems for the heat supply of residential buildings is carried out. Analysis of the numerical simulation showed that the operation of a heat pump system in a house heating mode under the geoclimatic conditions of the Moscow oblast leads to a temperature drop of the heat-exchange medium circulating through heat wells to 5-6°C by the end of the first 10 years of operation, and the process stabilizes by the 15th year of operation, and further changes in the heat-exchange medium temperature do not any longer significantly affect the temperature of the heat-exchange medium in the heat well. In this case, the exact dependence of the heat-exchange medium temperature drop on the depth is not revealed. Data on the economically expedient heat well depth for the conditions of the Moscow oblast ensuring a net present value for the whole residential building life cycle are presented. It is found that the heat well depth of 60 m can be considered as an endpoint for the Moscow oblast, and a further heat well deepening is economically impractical.

  20. Assessment of dynamic energy conversion systems for radioisotope heat sources

    International Nuclear Information System (INIS)

    Thayer, G.R.; Mangeng, C.A.

    1985-06-01

    The use of dynamic conversion systems to convert the heat generated in a 7500 W(t) 90 Sr radioisotopic heat source to electricity is examined. The systems studies were Stirling; Brayton Cycle; three organic Rankines (ORCs) (Barber-Nichols/ORMAT, Sundstrand, and TRW); and an organic Rankine plus thermoelectrics. The systems were ranked for a North Warning System mission using a Los Alamos Multiattribute Decision Theory code. Three different heat source designs were used: case I with a beginning of life (BOL) source temperature of 640 C, case II with a BOL source temperature of 745 0 C, and case III with a BOL source temperature of 945 0 C. The Stirling engine system was the top-ranked system of cases I and II, closely followed by the ORC systems in case I and ORC plus thermoelectrics in case II. The Brayton cycle system was top-ranked for case III, with the Stirling engine system a close second. The use of 238 Pu in heat source sizes of 7500 W(t) was examined and found to be questionable because of cost and material availability and because of additional requirements for analysis of safeguards and critical mass

  1. Natural convection in wavy enclosures with volumetric heat sources

    International Nuclear Information System (INIS)

    Oztop, H.F.; Varol, Y.; Abu-Nada, E.; Chamkha, A.

    2011-01-01

    In this paper, the effects of volumetric heat sources on natural convection heat transfer and flow structures in a wavy-walled enclosure are studied numerically. The governing differential equations are solved by an accurate finite-volume method. The vertical walls of enclosure are assumed to be heated differentially whereas the two wavy walls (top and bottom) are kept adiabatic. The effective governing parameters for this problem are the internal and external Rayleigh numbers and the amplitude of wavy walls. It is found that both the function of wavy wall and the ratio of internal Rayleigh number (Ra I ) to external Rayleigh number (Ra E ) affect the heat transfer and fluid flow significantly. The heat transfer is predicted to be a decreasing function of waviness of the top and bottom walls in case of (IRa/ERa)>1 and (IRa/ERa)<1. (authors)

  2. Heating effects in a liquid metal ion source

    International Nuclear Information System (INIS)

    Mair, G.L.R.; Aitken, K.L.

    1984-01-01

    A reassessment is made of the heating occurring at the anode of a liquid metal ion source, in the light of new microscopic observations. The apex region of the cones is in the form of a cusp, or jet, even at very low currents. The calculation for ohmic heating is conclusive for low currents; no heating occurs at the anode; for high currents (approx. 50-100 μA), substantial heating is conceivable, if a long, very thin, cylindrical jet exists at the apex of the anode. The answer to the problem of external heating, in the form of electrons bombarding the anode, is not quite conclusive; this is because of the impossibility of correctly assessing the electron flux entering the anode. However, it would appear to be a definite conclusion that for reasons of self-consistency field-ionisation of thermally released atoms cannot be a significant ion emission mechanism. (author)

  3. SELECTION OF HEAT SUPPLY SOURCE FOR MOBILE BUILDING STRUCTURE

    Directory of Open Access Journals (Sweden)

    T. I. Dolgikh

    2014-01-01

    Full Text Available The paper proposes a vortex heat generator with energy transformation of the highest  state  of matter motion  into  the  lowest  one  as  a  heat  supply  source  for a mobile object. Energy transformation coefficient indices close or equal to 1 have been obtained as a result of experiments on efficiency of the vortex heat generator. Such results can be explained with the help of the 2nd Bohr quantum postulate. Standard series of certified VTG heat generators has been proposed for heat supply of the mobile object (field hospital.

  4. Buoyancy induced convective flow in porous media with heat source

    International Nuclear Information System (INIS)

    Hwang, I.T.

    1978-01-01

    An unbounded fluid layer in a porous medium with an internal heat source and uniformly heated from below is studied. The layer is in the gravitational field. Linear theory predicts that the disturbances of infinitesimal amplitude will start to grow when the Rayleigh number exceeds its critical value. These disturbances do not grow without limit; but by advecting heat and momentum, the disturbances alter their forms to achieve a finite amplitude. Just like infinitesimal amplitude disturbances the degeneracies of possible solutions persist for finite amplitude solutions. This study evaluates these various forms of solutions. The small parameter method of Poincare is used to treat the problem in successive order

  5. Development of the Sixty Watt Heat-Source hardware components

    International Nuclear Information System (INIS)

    McNeil, D.C.; Wyder, W.C.

    1995-01-01

    The Sixty Watt Heat Source is a nonvented heat source designed to provide 60 thermal watts of power. The unit incorporates a plutonium-238 fuel pellet encapsulated in a hot isostatically pressed General Purpose Heat Source (GPHS) iridium clad vent set. A molybdenum liner sleeve and support components isolate the fueled iridium clad from the T-111 strength member. This strength member serves as the pressure vessel and fulfills the impact and hydrostatic strength requirements. The shell is manufactured from Hastelloy S which prevents the internal components from being oxidized. Conventional drawing operations were used to simplify processing and utilize existing equipment. The deep drawing reqirements for the molybdenum, T-111, and Hastelloy S were developed from past heat source hardware fabrication experiences. This resulted in multiple step drawing processes with intermediate heat treatments between forming steps. The molybdenum processing included warm forming operations. This paper describes the fabrication of these components and the multiple draw tooling developed to produce hardware to the desired specifications. copyright 1995 American Institute of Physics

  6. Nuclear heat source component design considerations for HTGR process heat reactor plant concept

    International Nuclear Information System (INIS)

    McDonald, C.F.; Kapich, D.; King, J.H.; Venkatesh, M.C.

    1982-01-01

    Using alternate energy sources abundant in the U.S.A. to help curb foreign oil imports is vitally important from both national security and economic standpoints. Perhaps the most forwardlooking opportunity to realize national energy goals involves the integrated use of two energy sources that have an established technology base in the U.S.A., namely nuclear energy and coal. The coupling of a high-temperature gas-cooled reactor (HTGR) and a chemical process facility has the potential for long-term synthetic fuel production (i.e., oil, gasoline, aviation fuel, hydrogen, etc.) using coal as the carbon source. Studies are in progress to exploit the high-temperature capability of an advanced HTGR variant for nuclear process heat. The process heat plant discussed in this paper has a 1170-MW(t) reactor as the heat source and the concept is based on indirect reforming, i.e., the high-temperature nuclear thermal energy is transported (via an intermediate heat exchanger (IHX)) to the externally located process plant by a secondary helium transport loop. Emphasis is placed on design considerations for the major nuclear heat source (NHS) components, and discussions are presented for the reactor core, prestressed concrete reactor vessel (PCRV), rotating machinery, and heat exchangers

  7. Heat Source Models in Simulation of Heat Flow in Friction Stir Welding

    DEFF Research Database (Denmark)

    Schmidt, Henrik Nikolaj Blich; Hattel, Jesper

    2004-01-01

    The objective of the present paper is to investigate the effect of including the tool probe and the material flow in the numerical modelling of heat flow in Friction Stir Welding (FSW). The contact condition at the interface between the tool and workpiece controls the heat transfer mechanisms....... The convective heat transfer due to the material flow affects the temperature fields. Models presented previously in literature allow the heat to flow through the probe volume, and the majority of them neglect the influence of the contact condition as the sliding condition is assumed. In the present work......, a number of cases are established. Each case represents a combination of a contact condition, i.e. sliding and sticking, and a stage of refinement regarding the heat source distribution. In the most detailed models the heat flow is forced around the probe volume by prescribing a velocity field in shear...

  8. Heat source models in simulation of heat flow in friction stir welding

    DEFF Research Database (Denmark)

    Schmidt, Henrik Nikolaj Blich; Hattel, Jesper

    2004-01-01

    The objective of the present paper is to investigate the effect of including the tool probe and the material flow in the numerical modelling of heat flow in friction stir welding (FSW). The contact condition at the interface between the tool and workpiece controls the heat transfer mechanisms....... The convective heat transfer due to the material flow affects the temperature fields. Models presented previously in the literature allow the heat to flow through the probe volume, and the majority neglects the influence of the contact condition as the sliding condition is assumed. In this work, a number...... of cases is established. Each case represents a combination of a contact condition, i.e. sliding and sticking, and a stage of refinement regarding the heat source distribution. In the most detailed models, the heat flow is forced around the probe volume by prescribing a velocity field in shear layers...

  9. Nuclear source of district heating in the north-east region of Russia

    International Nuclear Information System (INIS)

    Dolgov, V.V.

    1998-01-01

    The operation of the Bilibin Nuclear Co-generation Plant (BNCP) as a local district heating source is reviewed in this paper. Specific features of the BNCP power unit are given with special emphases on the components of the technological scheme, which are involved in the heat production and supply to the consumers. The scheme of steam extraction from the turbine, the flow diagram of steam in the turbine, as well as the three circuit heat removal system are described. The numerical characteristics of the nuclear heat supply system in various operating modes are presented. The real information characterizing current radiological conditions in the vicinity of the heat generation and distribution equipment is also presented in the paper. The BNCP technical and economical characteristics are compared with those of conventional energy sources. Both advantages and some problems revealed during the twenty-year experience of the BNCP nuclear heat utilization are generally assessed. Safety and reliability characteristics of the reactor and the heat supply system are also described. (author)

  10. Heat and mass release for some transient fuel source fires: A test report

    International Nuclear Information System (INIS)

    Nowlen, S.P.

    1986-10-01

    Nine fire tests using five different trash fuel source packages were conducted by Sandia National Laboratories. This report presents the findings of these tests. Data reported includes heat and mass release rates, total heat and mass release, plume temperatures, and average fuel heat of combustion. These tests were conducted as a part of the US Nuclear Regulatory Commission sponsored fire safety research program. Data from these tests were intended for use in nuclear power plant probabilistic risk assessment fire analyses. The results were also used as input to a fire test program at Sandia investigating the vulnerability of electrical control cabinets to fire. The fuel packages tested were chosen to be representative of small to moderately sized transient trash fuel sources of the type that would be found in a nuclear power plant. The highest fire intensity encountered during these tests was 145 kW. Plume temperatures did not exceed 820 0 C

  11. Encapsulated nuclear heat source reactors for energy security

    International Nuclear Information System (INIS)

    Greenspan, E.; Susplugas, A.; Hong, S.G.; Monti, L.; Sumini, M.; Okawa, T.

    2006-01-01

    A spectrum of Encapsulated Nuclear Heat Source (ENHS) reactors have been conceptually designed over the last few years; they span a power range from 10 MWe to -200 MWe and consider a number of coolants and fuel types. Common features of all these designs include very long life cores - exceeding 20 effective full power years; nearly zero burnup reactivity swing; natural circulation; superb safety; autonomous load following capability; simplicity of operation and maintenance. ENHS reactors could be of particular interest for providing electricity, thermal energy and, possibly, desalinated water to communities that are not connected to a central electricity grid such as to many pacific islands and to remote communities in the mainland of different countries. ENHS reactors provide energy security by virtue of a couple of features: (1) Once an ENHS reactor is commissioned, the community has assured clean energy supply for at least 20 years without needing fuel supply. (2) The energy value of the fuel loaded (in the factory) in the ENHS module is preserved; what is needed for generating energy for additional 20+ years is to remove the fission products, add depleted uranium for makeup fuel, refabricate fuel rods and load into a new module. This fuel recycling is envisioned done by either the supplier country or by a regional or international fuel cycle centre. As the ENHS module is replaced at its entirety at the end of the core life - that is brought about by radiation damage, the ENHS plant life is likely to last for over 100 years. The above features also offer exceptional stability in the price of energy generated by the ENHS reactor. The reference ENHS design will be described followed by a brief description of the design options developed and a summary of their performance characteristics

  12. Enhancing the Safety and Security of Radioactive Sources

    International Nuclear Information System (INIS)

    Hickey, J.

    2004-01-01

    The NRC initiatives to improve safety and security of sources began before 091101 and include both international and domestic activities. They supported the development and implementation of the IAEA Code of Conduct, which provides categorization of sources of concern, based on risk, improvement of regulatory programs of all member countries and improvement of safety and security of sources. International activities include the IAEA International Conference on Security of Sources (Vienna, Austria, March, 2003), the trilateral cooperation with Canada and Mexico, the assistance to individual countries to improve security and the proposed rule on export and import of radioactive material. The domestic initiatives are to issue the security orders and advisories to licensees, issue the panoramic irradiator orders (June 2003), issue the manufacturer orders (January 2004), complete the interim national source inventory, develop the national source tracking system, maintain the orphan source registration and retrieval program and upgrade the emergency preparedness

  13. Radiation protection and the safety of radiation sources

    International Nuclear Information System (INIS)

    1996-01-01

    These Safety Fundamentals cover the protection of human beings against ionizing radiation (gamma and X rays and alpha, beta and other particles that can induce ionization as they interact with biological materials), referred to herein subsequently as radiation, and the safety of sources that produce ionizing radiation. The Fundamentals do not apply to non-ionizing radiation such as microwave, ultraviolet, visible and infrared radiation. They do not apply either to the control of non-radiological aspects of health and safety. They are, however, part of the overall framework of health and safety

  14. Safety and security of radioactive sources - international provisions

    International Nuclear Information System (INIS)

    Czarwinski, R.; Weiss, W.

    2005-01-01

    For more than 50 years radioactive sources are used beneficially world-wide in medicine, industry, research and teaching. In the early 50ies mainly Ra-226 sources were used especially for medical applications. In the mean time a great number of radionuclides with more or less risk to individuals, society and environment are used. The number of these sources is increasing. The available experience with the application of sealed sources in industry, medicine, research and teaching shows that despite the widespread use of such sources a high level of safety can be achieved. One precondition is that the regulatory control of a radioactive source has to be carried out consistently during the life cycle of the sources - 'from cradle to grave'. Particular attention has to be given to the so-called orphan sources which are not subject to regulatory control, either because they have never been under control, or because they have been lost, misplaced, abandoned, stolen or transferred without proper authorisation. The concern about orphan sources arising from poor safety and security standards of radioactive material around the world resulted in intensive global actions especially in the light of the security situation after the 11 th September 2001. The improvement of regulatory control is one of the key elements in preventing people, goods and environment from being exposed exceptionally by the misuse of radioactive sources. Important steps toward the improvement of the safety and security of high radioactive sources are the IAEA Code of Conduct on the Safety and Security of Radioactive Sources and the European Directive on the Control of High Activity Sealed Radioactive Sources and Orphan Sources. (orig.)

  15. Fatal Exertional Heat Stroke and American Football Players: The Need for Regional Heat-Safety Guidelines.

    Science.gov (United States)

    Grundstein, Andrew J; Hosokawa, Yuri; Casa, Douglas J

    2018-01-01

      Weather-based activity modification in athletics is an important way to minimize heat illnesses. However, many commonly used heat-safety guidelines include a uniform set of heat-stress thresholds that do not account for geographic differences in acclimatization.   To determine if heat-related fatalities among American football players occurred on days with unusually stressful weather conditions based on the local climate and to assess the need for regional heat-safety guidelines.   Cross-sectional study.   Data from incidents of fatal exertional heat stroke (EHS) in American football players were obtained from the National Center for Catastrophic Sport Injury Research and the Korey Stringer Institute.   Sixty-one American football players at all levels of competition with fatal EHSs from 1980 to 2014.   We used the wet bulb globe temperature (WBGT) and a z-score WBGT standardized to local climate conditions from 1991 to 2010 to assess the absolute and relative magnitudes of heat stress, respectively.   We observed a poleward decrease in exposure WBGTs during fatal EHSs. In milder climates, 80% of cases occurred at above-average WBGTs, and 50% occurred at WBGTs greater than 1 standard deviation from the long-term mean; however, in hotter climates, half of the cases occurred at near average or below average WBGTs.   The combination of lower exposure WBGTs and frequent extreme climatic values in milder climates during fatal EHSs indicates the need for regional activity-modification guidelines with lower, climatically appropriate weather-based thresholds. Established activity-modification guidelines, such as those from the American College of Sports Medicine, work well in the hotter climates, such as the southern United States, where hot and humid weather conditions are common.

  16. Sources and basic threats of biological safety

    International Nuclear Information System (INIS)

    Nazarova, O.D.

    2010-01-01

    Full text: Biological safety of any state is connected with development of its public protection against biological weapons and opportunity to prevent bio terrorist attacks. That's why in modern social-economic and geo-political conditions, the problem of biological safety strengthening become significant, which is connected with migration process globalization, development of bio-technology and dramatically increased risk of pathogenic germ infections proliferation, which can be used as biological weapon. Despite of undertaken efforts by world community on full prohibition of biological weapon, its proliferation in the world still takes place. Biology revolution during second and third millennium lead to development not only biotechnology but new achievements in medicine, agriculture and other fields of economy, but also created scientific and research preconditions for development of advanced biological means of mass destruction, that make it more attractive for achieving superiority and assigned targets: low developments costs, opportunity to create it by one small laboratory with two-three high qualified specialists bio technologists; tremendous impact effect: one substance gram can contain from one till one hundreds quintillions (10"1"8 - 10"2"0) active pathogen molecules and in case if they belong to amplificated RNA and DNA, each molecule getting to organism, will multiply and contaminate environment (the last one is its principal difference from chemical weapon); bypass of organism immunological barriers and specific vaccinations; unusual clinic finding, hard diagnosis; weakness of traditional medications and treatment methods; lack of material destruction; opportunity of tight-lipped developments; opportunity of tight-lipped application; opportunity of delayed effect; opportunity of selective influence on specific population (by use of genetic, climatic and cultural specifications of race, nations and nationalities). Above mentioned specifications create

  17. Radiation sources safety and radioactive materials security regulation in Ukraine

    International Nuclear Information System (INIS)

    Smyshliaiev, A.; Holubiev, V.; Makarovska, O.

    2001-01-01

    Radiation sources are widely used in Ukraine. There are about 2500 users in industry, science, education and about 2800 in medicine. About 80,000 sealed radiation sources with total kerma-equivalent of 450 Gy*M 2 /sec are used in Ukraine. The exact information about the radiation sources and their users will be provided in 2001 after the expected completion of the State inventory of radiation sources in Ukraine. In order to ensure radiation source safety in Ukraine, a State System for regulation of activities dealing with radiation sources has been established. The system includes the following elements: establishment of norms, rules and standards of radiation safety; authorization activity, i.e. issuance of permits (including those in the form of licences) for activities dealing with radiation sources; supervisory activity, i.e. control over observance of norms, rules and standards of radiation safety and fulfilment of conditions of licences for activities dealing with radiation sources, and also enforcement. Comprehensive nuclear legislation was developed and implemented from 1991 to 2000. Radiation source safety is regulated by three main nuclear laws in Ukraine: On the use of nuclear energy and radiation safety (passed on 8 February 1995); On Human Protection from Impact of Ionizing Radiation (passed on 14 January 1998); On permissive activity in the area of nuclear energy utilization (passed on 11 January 2000). The regulatory authorities in Ukraine are the Ministry for Ecology and Natural Resources (Nuclear Regulatory Department) and the Ministry of Health (State sanitary-epidemiology supervision). According to the legislation, activities dealing with radiation sources are forbidden without an officially issued permit in Ukraine. Permitted activities with radiation sources are envisaged: licensing of production, storage and maintenance of radiation sources; licensing of the use of radiation sources; obligatory certification of radiation sources and transport

  18. Passive safety systems for decay heat removal of MRX

    Energy Technology Data Exchange (ETDEWEB)

    Ochiai, M; Iida, H; Hoshi, T [Japan Atomic Energy Research Inst., Ibaraki (Japan). Nuclear Ship System Lab.

    1996-12-01

    The MRX (marine Reactor X) is an advanced marine reactor, its design has been studied in Japan Atomic Energy Research Institute. It is characterized by four features, integral type PWR, in-vessel type control rod drive mechanisms, water-filled containment vessel and passive decay heat removal system. A water-filled containment vessel is of great advantage since it ensures compactness of a reactor plant by realizing compact radiation shielding. The containment vessel also yields passive safety of MRX in the event of a LOCA by passively maintaining core flooding without any emergency water injection. Natural circulation of water in the vessels (reactor and containment vessels) is one of key factors of passive decay heat removal systems of MRX, since decay heat is transferred from fuel rods to atmosphere by natural circulation of the primary water, water in the containment vessel and thermal medium in heat pipe system for the containment vessel water cooling in case of long terms cooling after a LOCA as well as after reactor scram. Thus, the ideal of water-filled containment vessel is considered to be very profitable and significant in safety and economical point of view. This idea is, however, not so familiar for a conventional nuclear system, so experimental and analytical efforts are carried out for evaluation of hydrothermal behaviours in the reactor pressure vessel and in the containment vessel in the event of a LOCA. The results show the effectiveness of the new design concept. Additional work will also be conducted to investigate the practical maintenance of instruments in the containment vessel. (author). 4 refs, 9 figs, 2 tabs.

  19. Current status of ground-source heat pumps in China

    International Nuclear Information System (INIS)

    Yang Wei; Zhou Jin; Xu Wei; Zhang Guoqiang

    2010-01-01

    As a renewable energy technology, the ground-source heat pump (GSHP) technologies have increasingly attracted world-wide attention due to their advantages of energy efficiency and environmental friendliness. This paper presents Chinese research and application on GSHP followed by descriptions of patents. The policies related to GSHP are also introduced and analyzed. With the support of Chinese government, several new heat transfer models and two new GSHP systems (named pumping and recharging well (PRW) and integrated soil cold storage and ground-source heat pump (ISCS and GSHP) system) have been developed by Chinese researchers. The applications of GSHP systems have been growing rapidly since the beginning of the 21st century with financial incentives and supportive government policies. However, there are still several challenges for the application of GSHP systems in large scale. This paper raises relevant suggestions for overcoming the existing and potential obstacles. In addition, the developing and applying prospects of GSHP systems in China are also discussed.

  20. Absorptivity Measurements and Heat Source Modeling to Simulate Laser Cladding

    Science.gov (United States)

    Wirth, Florian; Eisenbarth, Daniel; Wegener, Konrad

    The laser cladding process gains importance, as it does not only allow the application of surface coatings, but also additive manufacturing of three-dimensional parts. In both cases, process simulation can contribute to process optimization. Heat source modeling is one of the main issues for an accurate model and simulation of the laser cladding process. While the laser beam intensity distribution is readily known, the other two main effects on the process' heat input are non-trivial. Namely the measurement of the absorptivity of the applied materials as well as the powder attenuation. Therefore, calorimetry measurements were carried out. The measurement method and the measurement results for laser cladding of Stellite 6 on structural steel S 235 and for the processing of Inconel 625 are presented both using a CO2 laser as well as a high power diode laser (HPDL). Additionally, a heat source model is deduced.

  1. Weldability of general purpose heat source new-process iridium

    International Nuclear Information System (INIS)

    Kanne, W.R.

    1987-01-01

    Weldability tests on General Purpose Heat Source (GPHS) iridium capsules showed that a new iridium fabrication process reduced susceptibility to underbead cracking. Seventeen capsules were welded (a total of 255 welds) in four categories and the number of cracks in each weld was measured

  2. General-purpose heat source development. Phase I: design requirements

    International Nuclear Information System (INIS)

    Snow, E.C.; Zocher, R.W.

    1978-09-01

    Studies have been performed to determine the necessary design requirements for a 238 PuO 2 General-Purpose Heat Source (GPHS). Systems and missions applications, as well as accident conditions, were considered. The results of these studies, along with the recommended GPHS design requirements, are given in this report

  3. Thermal hydraulic analysis of the encapsulated nuclear heat source

    Energy Technology Data Exchange (ETDEWEB)

    Sienicki, J.J.; Wade, D.C. [Argonne National Lab., IL (United States)

    2001-07-01

    An analysis has been carried out of the steady state thermal hydraulic performance of the Encapsulated Nuclear Heat Source (ENHS) 125 MWt, heavy liquid metal coolant (HLMC) reactor concept at nominal operating power and shutdown decay heat levels. The analysis includes the development and application of correlation-type analytical solutions based upon first principles modeling of the ENHS concept that encompass both pure as well as gas injection augmented natural circulation conditions, and primary-to-intermediate coolant heat transfer. The results indicate that natural circulation of the primary coolant is effective in removing heat from the core and transferring it to the intermediate coolant without the attainment of excessive coolant temperatures. (authors)

  4. Research on neutron source multiplication method in nuclear critical safety

    International Nuclear Information System (INIS)

    Zhu Qingfu; Shi Yongqian; Hu Dingsheng

    2005-01-01

    The paper concerns in the neutron source multiplication method research in nuclear critical safety. Based on the neutron diffusion equation with external neutron source the effective sub-critical multiplication factor k s is deduced, and k s is different to the effective neutron multiplication factor k eff in the case of sub-critical system with external neutron source. The verification experiment on the sub-critical system indicates that the parameter measured with neutron source multiplication method is k s , and k s is related to the external neutron source position in sub-critical system and external neutron source spectrum. The relation between k s and k eff and the effect of them on nuclear critical safety is discussed. (author)

  5. Environmental radiation safety source term evaluation program

    International Nuclear Information System (INIS)

    Moss, O.R.; Filipy, R.E.; Cannon, W.C.; Craig, D.K.

    1977-04-01

    Plutonium-238 is currently used in the form of a pure refractory oxide as a power source on a number of space vehicles that have already been or will be launched during the next few years. Although the sources are designed and built to withstand re-entry into the earth's atmosphere and impact with the earth's surface without releasing any plutonium, the possibility of such an event can never be absolutely excluded. Three separate tasks were undertaken in this study. The interactions between soils and 238 PuO 2 aerosols which might be created in a space launch about environment were examined. Aging of the plutonium-soil mixture under a humid atmosphere showed a trend toward the slow coagulation of two dilute aerosols. Studies on marine animals were conducted to assess the response of 238 PuO 2 pellets to conditions found 60 feet below the ocean surface. Ultrafilterability studies measured the solubility of 238 PuO 2 as a function of time, temperature, suspension concentration and molality of solvent

  6. Discussion on application of water source heat pump technology to uranium mines

    International Nuclear Information System (INIS)

    An Qiang

    2011-01-01

    Application of water source heat pump units in recovering waste heat from uranium mines is discussed, and several forms of waste heat recovery are introduced. The problems in the application of water source heat pump technology are analyzed. Analysis results show that the water source heat pump technology has broad application prospects in uranium mines, and it is a way to exchange existing structure of heat and cold sources in uranium mines. (authors)

  7. Ground Source Heat Pump Sub-Slab Heat Exchange Loop Performance in a Cold Climate

    Energy Technology Data Exchange (ETDEWEB)

    Mittereder, N.; Poerschke, A.

    2013-11-01

    This report presents a cold-climate project that examines an alternative approach to ground source heat pump (GSHP) ground loop design. The innovative ground loop design is an attempt to reduce the installed cost of the ground loop heat exchange portion of the system by containing the entire ground loop within the excavated location beneath the basement slab. Prior to the installation and operation of the sub-slab heat exchanger, energy modeling using TRNSYS software and concurrent design efforts were performed to determine the size and orientation of the system. One key parameter in the design is the installation of the GSHP in a low-load home, which considerably reduces the needed capacity of the ground loop heat exchanger. This report analyzes data from two cooling seasons and one heating season. Upon completion of the monitoring phase, measurements revealed that the initial TRNSYS simulated horizontal sub-slab ground loop heat exchanger fluid temperatures and heat transfer rates differed from the measured values. To determine the cause of this discrepancy, an updated model was developed utilizing a new TRNSYS subroutine for simulating sub-slab heat exchangers. Measurements of fluid temperature, soil temperature, and heat transfer were used to validate the updated model.

  8. Ground Source Heat Pump Sub-Slab Heat Exchange Loop Performance in a Cold Climate

    Energy Technology Data Exchange (ETDEWEB)

    Mittereder, Nick [IBACOS, Inc., Pittsburgh, PA (United States); Poerschke, Andrew [IBACOS, Inc., Pittsburgh, PA (United States)

    2013-11-01

    This report presents a cold-climate project that examines an alternative approach to ground source heat pump (GSHP) ground loop design. The innovative ground loop design is an attempt to reduce the installed cost of the ground loop heat exchange portion of the system by containing the entire ground loop within the excavated location beneath the basement slab. Prior to the installation and operation of the sub-slab heat exchanger, energy modeling using TRNSYS software and concurrent design efforts were performed to determine the size and orientation of the system. One key parameter in the design is the installation of the GSHP in a low-load home, which considerably reduces the needed capacity of the ground loop heat exchanger. This report analyzes data from two cooling seasons and one heating season.

  9. Self-Heating Effects In Polysilicon Source Gated Transistors

    Science.gov (United States)

    Sporea, R. A.; Burridge, T.; Silva, S. R. P.

    2015-01-01

    Source-gated transistors (SGTs) are thin-film devices which rely on a potential barrier at the source to achieve high gain, tolerance to fabrication variability, and low series voltage drop, relevant to a multitude of energy-efficient, large-area, cost effective applications. The current through the reverse-biased source barrier has a potentially high positive temperature coefficient, which may lead to undesirable thermal runaway effects and even device failure through self-heating. Using numerical simulations we show that, even in highly thermally-confined scenarios and at high current levels, self-heating is insufficient to compromise device integrity. Performance is minimally affected through a modest increase in output conductance, which may limit the maximum attainable gain. Measurements on polysilicon devices confirm the simulated results, with even smaller penalties in performance, largely due to improved heat dissipation through metal contacts. We conclude that SGTs can be reliably used for high gain, power efficient analog and digital circuits without significant performance impact due to self-heating. This further demonstrates the robustness of SGTs. PMID:26351099

  10. Radioactive heat source and method of making same

    International Nuclear Information System (INIS)

    Elsner, N.B.

    1977-01-01

    A radioactive source of heat which is resistant to cremation conditions is made by encapsulating a radioisotope within a containment vessel and forming a refractory metal silicide diffusion coating exterior thereof. A secondary molybdenum vessel may be provided with a molybdenum silicide coating and then heated in air to oxidize its outer layer. A layer is applied exterior of the diffusion-coating which provides a continuous ceramic oxide layer upon subjection to cremation. This outer layer may be discrete silica carried in a hardenable binder of an organic polymer, and a minor amount of antimony is preferably also included

  11. Promising design options for the encapsulated nuclear heat source reactor

    Energy Technology Data Exchange (ETDEWEB)

    Conway, L.; Carelli, M.D.; Dzodzo, M. [Westinghouse Science and Technology, Pittsburgh, PA (United States); Hossain, Q.; Brown, N.W. [Lawrence Livermore National Lab., CA (United States); Wade, D.C.; Sienick, J.J. [Argonne National Lab., IL (United States); Greenspan, E.; Kastenberg, W.E.; Saphier, D. [University of California Dept of Nuclear Engineering, Berkeley, CA (United States)

    2001-07-01

    Promising design options for the Encapsulated Nuclear Heat Source (ENHS) liquid-metal cooled fast reactor were identified during the first year of the DOE NERI program sponsored feasibility study. Many opportunities for incorporation of innovations in design and fabrication were identified. Three of the innovations are hereby described: a novel IHX (intermediate heat exchanger) made of a relatively small number of rectangular channels, an ENHS module design featuring 100% natural circulation, and a novel conceptual design of core support and fuelling. As a result of the first year study the ENHS concept appears more practical and more promising than perceived at the outset of this study. (authors)

  12. Promising design options for the encapsulated nuclear heat source reactor

    International Nuclear Information System (INIS)

    Conway, L.; Carelli, M.D.; Dzodzo, M.; Hossain, Q.; Brown, N.W.; Wade, D.C.; Sienick, J.J.; Greenspan, E.; Kastenberg, W.E.; Saphier, D.

    2001-01-01

    Promising design options for the Encapsulated Nuclear Heat Source (ENHS) liquid-metal cooled fast reactor were identified during the first year of the DOE NERI program sponsored feasibility study. Many opportunities for incorporation of innovations in design and fabrication were identified. Three of the innovations are hereby described: a novel IHX (intermediate heat exchanger) made of a relatively small number of rectangular channels, an ENHS module design featuring 100% natural circulation, and a novel conceptual design of core support and fuelling. As a result of the first year study the ENHS concept appears more practical and more promising than perceived at the outset of this study. (authors)

  13. Ground-source heat pump systems in Norway

    International Nuclear Information System (INIS)

    Stene, Joern

    2007-01-01

    The Norwegian ground source heat pump (GSHP) market is reviewed. Boreholes in bedrock are of growing interest for residential systems and of growing interest for larger systems with thermal recharging or thermal energy storage. Ground water is limited to areas where the water has acceptable purity. Challenges and important boundary conditions include 1) high quality GSHP system requires engineering expertise, 2) new building codes and EU directive 'energy performance of buildings.'(2006), and 3) hydronic floor heating systems in 50 percent of new residences (author) (ml)

  14. Heat pump using dual heat sources of air and water. Performance in cooling mode; Mizu kuki ryonetsugen heat pump no kenkyu. Reibo unten ni okeru seino

    Energy Technology Data Exchange (ETDEWEB)

    Ito, S; Miura, N [Kanagawa Institute of Technology, Kanagawa (Japan); Uchikawa, Y [Kubota Corp., Osaka (Japan)

    1997-11-25

    When a heat pump is used for cooling purpose, it is possible to utilize different kinds of waste water as high-heat sources. However, these heat sources would have their temperatures vary with seasons and time in a day. Therefore, a discussion was given on performance of a heat pump when water and air heat sources are used for condensers during cooling operation independently, in series and in parallel, respectively. The air condenser shows an equivalent COP as compared with the water condenser when air temperature is lower by about 8 degC than water temperature. At the same heat source temperature, the COP for the water condenser indicated a value higher by about 0.6 than the case of the air condenser. A method to use condensers in parallel experiences little contribution from the air heat source, and performance of the heat pump decreases below the case of using the water heat source independently when the air heat source temperature becomes higher than that of the water heat source. In the case of series use in which a water condenser is installed in front and an air condenser in rear, its effect is exhibited when temperature in the air heat source is lower than that in the water heat source. Better performance was shown than in operating the water heat source independently. 2 refs., 9 figs.

  15. Radiation safety and inventory of sealed radiation sources in Pakistan

    International Nuclear Information System (INIS)

    Ali, M.; Mannan, A.

    2001-01-01

    Sealed radiation sources (SRS) of various types and activities are widely used in industry, medicine, agriculture, research and teaching in Pakistan. The proper maintenance of records of SRS is mandatory for users/licensees. Since 1956, more than 2000 radiation sources of different isotopes having activities of Bq to TBq have been imported. Of these, several hundred sources have been disposed of and some have been exported/returned to the suppliers. To ensure the safety and security of the sources and to control and regulate the safe use of radiation sources in various disciplines, the Directorate of Nuclear Safety and Radiation Protection (DNSRP), the implementing arm of the regulatory authority in the country, has introduced a system for notifying, registering and licensing the use of all types of SRS. In order to update the inventory of SRS used throughout the country, the DNSRP has developed a database. (author)

  16. The safety of radiation sources and radioactive materials in China

    International Nuclear Information System (INIS)

    Liu, H.

    2001-01-01

    The report describes the present infrastructure for the safety of radiation sources in China, where applications of radiation sources have become more and more widespread in the past years. In particular, it refers to the main functions of the National Nuclear Safety Administration of the State Environmental Protection Administration (SEPA), which is acting as the regulatory body for nuclear and radiation safety at nuclear installations, the Ministry of Public Health which issues licences for the use of radiation sources, and the Ministry of Public Security, which deals with the security of radiation sources. The report also refers to the main requirements of the existing regulatory system for radiation safety, i.e. the basic dose limits for radiation workers and the public, the licensing system for nuclear installations and for radioisotope-based and other irradiation devices, and the environmental impact assessment system. Information on the nationwide survey of radiation sources carried out by SEPA in 1991 is provided, and on some accidents that occurred in China due to loss of control of radiation sources and errors in the operation of irradiation facilities. (author)

  17. Probing the heat sources during thermal runaway process by thermal analysis of different battery chemistries

    Science.gov (United States)

    Zheng, Siqi; Wang, Li; Feng, Xuning; He, Xiangming

    2018-02-01

    Safety issue is very important for the lithium ion battery used in electric vehicle or other applications. This paper probes the heat sources in the thermal runaway processes of lithium ion batteries composed of different chemistries using accelerating rate calorimetry (ARC) and differential scanning calorimetry (DSC). The adiabatic thermal runaway features for the 4 types of commercial lithium ion batteries are tested using ARC, whereas the reaction characteristics of the component materials, including the cathode, the anode and the separator, inside the 4 types of batteries are measured using DSC. The peaks and valleys of the critical component reactions measured by DSC can match the fluctuations in the temperature rise rate measured by ARC, therefore the relevance between the DSC curves and the ARC curves is utilized to probe the heat source in the thermal runaway process and reveal the thermal runaway mechanisms. The results and analysis indicate that internal short circuit is not the only way to thermal runaway, but can lead to extra electrical heat, which is comparable with the heat released by chemical reactions. The analytical approach of the thermal runaway mechanisms in this paper can guide the safety design of commercial lithium ion batteries.

  18. Evaluation and characterization of General Purpose Heat Source girth welds for the Cassini mission

    International Nuclear Information System (INIS)

    Lynch, C.M.; Moniz, P.F.; Reimus, M.A.H.

    1998-01-01

    General Purpose Heat Sources (GPHSs) are components of Radioisotopic thermoelectric Generators (RTGs) which provide electric power for deep space missions. Each GPHS consists of a 238 Pu oxide ceramic pellet encapsulated in a welded iridium alloy shell which forms a protective barrier against the release of plutonia in the unlikely event of a launch-pad failure or reentry incident. GPHS fueled clad girth weld flaw detection was paramount to ensuring this safety function, and was accomplished using both destructive and non-destructive evaluation techniques. The first girth weld produced from each welding campaign was metallographically examined for flaws such as incomplete weld penetration, cracks, or porosity which would render a GPHS unacceptable for flight applications. After an acceptable example weld was produced, the subsequently welded heat sources were evaluated non-destructively for flaws using ultrasonic immersion testing. Selected heat sources which failed ultrasonic testing would be radiographed, and/or, destructively evaluated to further characterize and document anomalous indications. Metallography was also performed on impacted heat sources to determine the condition of the welds

  19. Probabilist methods applied to electric source problems in nuclear safety

    International Nuclear Information System (INIS)

    Carnino, A.; Llory, M.

    1979-01-01

    Nuclear Safety has frequently been asked to quantify safety margins and evaluate the hazard. In order to do so, the probabilist methods have proved to be the most promising. Without completely replacing determinist safety, they are now commonly used at the reliability or availability stages of systems as well as for determining the likely accidental sequences. In this paper an application linked to the problem of electric sources is described, whilst at the same time indicating the methods used. This is the calculation of the probable loss of all the electric sources of a pressurized water nuclear power station, the evaluation of the reliability of diesels by event trees of failures and the determination of accidental sequences which could be brought about by the 'total electric source loss' initiator and affect the installation or the environment [fr

  20. Quasiballistic heat removal from small sources studied from first principles

    Science.gov (United States)

    Vermeersch, Bjorn; Mingo, Natalio

    2018-01-01

    Heat sources whose characteristic dimension R is comparable to phonon mean free paths display thermal resistances that exceed conventional diffusive predictions. This has direct implications to (opto)electronics thermal management and phonon spectroscopy. Theoretical analyses have so far limited themselves to particular experimental configurations. Here, we build upon the multidimensional Boltzmann transport equation (BTE) to derive universal expressions for the apparent conductivity suppression S (R ) =κeff(R ) /κbulk experienced by radially symmetric 2D and 3D sources. In striking analogy to cross-plane heat conduction in thin films, a distinct quasiballistic regime emerges between ballistic (κeff˜R ) and diffusive (κeff≃κbulk ) asymptotes that displays a logarithmic dependence κeff˜ln(R ) in single crystals and fractional power dependence κeff˜R2 -α in alloys (with α the Lévy superdiffusion exponent). Analytical solutions and Monte Carlo simulations for spherical and circular heat sources in Si, GaAs, Si0.99Ge0.01 , and Si0.82Ge0.18 , all carried out from first principles, confirm the predicted generic tendencies. Contrary to the thin film case, common approximations like kinetic theory estimates κeff≃∑Sωgreyκω and modified Fourier temperature curves perform relatively poorly. Up to threefold deviations from the BTE solutions for sub-100 nm sources underline the need for rigorous treatment of multidimensional nondiffusive transport.

  1. Design of serially connected ammonia-water hybrid absorption-compression heat pumps for district heating with the utilisation of a geothermal heat source

    DEFF Research Database (Denmark)

    Jensen, Jonas Kjær; Ommen, Torben Schmidt; Markussen, Wiebke Brix

    2016-01-01

    District heating (DH) can reduce the primary energy consumption in urban areas with significant heat demands. The design of a serially connected ammonia-water hybrid absorption-compression heat pump system was investigated for operation in the Greater Copenhagen DH network in Denmark, in order...... to supply 7.2 MW heat at 85 °C utilizing a geothermal heat source at 73 °C. Both the heat source and heat sink experience a large temperature change over the heat transfer process, of which a significant part may be achieved by direct heat exchange. First a generic study with a simple representation...

  2. Thermodynamic analysis on an instantaneous water heating system of shower wastewater source heat pump

    Directory of Open Access Journals (Sweden)

    Yuguo Wu

    2018-09-01

    Full Text Available Water reuse and desalination systems are energy intensive processes, and their increasing use is leading energy consumption within water systems to be an increasingly important issue. Shower wastewater contains large amounts of heat, so there is an opportunity to recover energy from shower water to offset energy consumption elsewhere in water systems. This paper found ways to increase the output of hot water and lower the energy consumption by establishing a thermodynamic model of an instantaneous wastewater source heat pump. The system proved to be very effective, the heating COP (coefficient of performance can reach 3.3 even in the winter. Under the conditions of limited heat transfer area, reducing the suction pressure of a compressor is a more feasible way to increase the hot water output to meet the needs of users rather than increasing the discharge pressure. Besides, increasing the heat transfer area of the evaporator is a more effective option. When the heat transfer area of evaporator varies from 0.5 to 1.0 square meters, a notable change is that the heating COP increases from 3.283 to 3.936. The heating COP in a system with a recuperator can reach 5.672, almost double that compared to the original systems.

  3. A feasible system integrating combined heating and power system with ground-source heat pump

    International Nuclear Information System (INIS)

    Li, HongQiang; Kang, ShuShuo; Yu, Zhun; Cai, Bo; Zhang, GuoQiang

    2014-01-01

    A system integrating CHP (combined heating and power) subsystem based on natural gas and GSHP (ground-source heat pump subsystem) in series is proposed. By help of simulation software-Aspen Plus, the energy performance of a typical CHP and GSHP-S (S refers to ‘in series’) system was analyzed. The results show that the system can make a better use of waste heat in flue gas from CHP (combined heating and power subsystem). The total system energy efficiency is 123% and the COP (coefficient of performance) of GSHP (ground-source heat pump) subsystem is 5.3. A referenced CHP and GSHP-P (P refers to ‘in parallel’) system is used for comparison; its total system energy efficiency and COP of GSHP subsystem are 118.6% and 3.5 respectively. Compared with CHP and GSHP-P system with different operating parameters, the CHP and GSHP-S system can increase total system energy efficiency by 0.8–34.7%, with related output ratio of heat to power (R) from 1.9 to 18.3. Furthermore, the COP of GSHP subsystem can be increased between the range 3.6 and 6, which is much higher than that in conventional CHP and GSHP-P system. This study will be helpful for other efficient GSHP systems integrating if there is waste heat or other heat resources with low temperature. - Highlights: • CHP system based on natural gas and ground source heat pump. • The new system can make a better utilization of waste heat in flue gas by a special way. • The proposed system can realize energy saving potential from 0.8 to 34.7%. • The coefficient of performance of ground source heat pump subsystem is significantly improved from 3.5 to 3.6–6. • Warm water temperature and percentage of flue gas used to reheat are key parameters

  4. Solar heating as a major source of energy for Australia

    Energy Technology Data Exchange (ETDEWEB)

    Morse, R. N.

    1977-07-01

    Solar energy can make its most effective contribution to Australian primary energy in the form of heat for industrial applications. About 50% of all end use energy is required as heat and it is estimated that 40% of this amounting to 1 EJ/a by 2000 could be supplied by solar heat generating systems. This would be 12% of estimated primary energy requirements by that time, and could help reduce the country's increasing dependence on imported oil. Energy self-sufficiency for Australia is possible, based on coal, solar energy and natural gas as primary energy sources. The reason for the present orientation towards residential solar water heaters is that there are many places where electric power for water heating costs between 2 and 4 cents per kWh which makes a solar water heater an attractive proposition. There is also a growing interest in the solar heating of swimming pools, mostly for private homes but also in larger installations for public and institutional pools. Industrial applications, on the other hand, are inhibited by the current low energy prices in Australia, which in some cases are around 0.13 cents/MJ (.47 cents/kWh). Industry, however, uses 40% of Australian primary energy, and represents by far the greatest potential for solar heat generating systems. Demonstration plants are being planned to obtain data on capital and running costs, and at the same time build up professional design and constructional skills in this area. The first demonstration solar industrial process heating system was commissioned in December 1976 and supplies portion of the heat requirements of a soft drink plant in conjunction with the existing oil fired boiler. Integrated solar/oil fired systems of this sort ensure continuous operation of the plant and over a year can result in significant oil savings.

  5. Solar heating as a major source of energy for Australia

    Energy Technology Data Exchange (ETDEWEB)

    Morse, R.N.

    1977-07-01

    Solar energy can make its most effective contribution to Australian primary energy in the form of heat for industrial applications. About 50% of all end use energy is required as heat and it is estimated that 40% of this amounting to 1 EJ/a by 2000 could be supplied by solar heat generating systems. This would be 12% of estimated primary energy requirements by that time, and could help reduce the country's increasing dependence on imported oil. Energy self-sufficiency for Australia is possible, based on coal, solar energy and natural gas as primary energy sources. The reason for the present orientation towards residential solar water heaters is that there are many places where electric power for water heating costs between 2 and 4 cents per kWh which makes a solar water heater an attractive proposition. There is also a growing interest in the solar heating of swimming pools, mostly for private homes but also in larger installations for public and institutional pools. Industrial applications, on the other hand, are inhibited by the current low energy prices in Australia, which in some cases are around 0.13 cents/MJ (.47 cents/kWh). Industry, however, uses 40% of Australian primary energy, and represents by far the greatest potential for solar heat generating systems. Demonstration plants are being planned to obtain data on capital and running costs, and at the same time build up professional design and constructional skills in this area. The first demonstration solar industrial process heating system was commissioned in December 1976 and supplies portion of the heat requirements of a soft drink plant in conjunction with the existing oil fired boiler. Integrated solar/oil fired systems of this sort ensure continuous operation of the plant and over a year can result in significant oil savings.

  6. The advanced neutron source facility: Safety philosophy and studies

    International Nuclear Information System (INIS)

    Greene, S.R.; Harrington, R.M.

    1988-01-01

    The Advanced Neutron Source (ANS) is currently the only new civilian nuclear reactor facility proposed for construction in the United States. Even though the thermal power of this research-oriented reactor is a relatively low 300 MW, the design will undoubtedly receive intense scrutiny before construction is allowed to proceed. Safety studies are already under way to ensure that the maximum degree of safety in incorporated into the design and that the design is acceptable to the Department of Energy (DOE) and can meet the Nuclear Regulatory Commission regulations. This document discusses these safety studies

  7. The Advanced Light Source (ALS) Radiation Safety System

    International Nuclear Information System (INIS)

    Ritchie, A.L.; Oldfather, D.E.; Lindner, A.F.

    1993-08-01

    The Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory (LBL) is a 1.5 Gev synchrotron light source facility consisting of a 120 kev electron gun, 50 Mev linear accelerator, 1.5 Gev booster synchrotron, 200 meter circumference electron storage ring, and many photon beamline transport systems for research. Figure 1. ALS floor plan. Pairs of neutron and gamma radiation monitors are shown as dots numbered from 1 to 12. The Radiation Safety System for the ALS has been designed and built with a primary goal of providing protection against inadvertent personnel exposure to gamma and neutron radiation and, secondarily, to enhance the electrical safety of select magnet power supplies

  8. The Advanced Light Source (ALS) Radiation Safety System

    International Nuclear Information System (INIS)

    Ritchie, A.; Oldfather, D.; Lindner, A.

    1993-05-01

    The Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory (LBL) is a 1.5 GeV synchrotron light source facility consisting of a 120 keV electron gun, 50 MeV linear accelerator, 1.5 Gev booster synchrotron, 200 meter circumference electron storage ring, and many photon beamline transport systems for research. The Radiation Safety System for the ALS has been designed and built with a primary goal of providing protection against inadvertent personnel exposure to gamma and neutron radiation and, secondarily, to enhance the electrical safety of select magnet power supplies

  9. Advanced control for ground source heat pump systems

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, Patrick [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gehl, Anthony C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Liu, Xiaobing [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-09-01

    Ground source heat pumps (GSHP), also known as geothermal heat pumps (GHP), are proven advanced HVAC systems that utilize clean and renewable geothermal energy, as well as the massive thermal storage capacity of the ground, to provide space conditioning and water heating for both residential and commercial buildings. GSHPs have higher energy efficiencies than conventional HVAC systems. It is estimated, if GSHPs achieve a 10% market share in the US, in each year, 0.6 Quad Btu primary energy consumption can be saved and 36 million tons carbon emissions can be avoided (Liu et al. 2017). However, the current market share of GSHPs is less than 1%. The foremost barrier preventing wider adoption of GSHPs is their high installation costs. To enable wider adoption of GSHPs, the costeffectiveness of GSHP applications must be improved.

  10. The impact of municipal waste combustion in small heat sources

    Science.gov (United States)

    Vantúch, Martin; Kaduchová, Katarína; Lenhard, Richard

    2016-06-01

    At present there is a tendency to make greater use for heating houses for burning solid fuel, such as pieces of wood, coal, coke, local sources of heat to burn natural gas. This tendency is given both the high price of natural gas as well as the availability of cheaper solid fuel. In many cases, in the context saving heating costs, respectively in the context of the disposal of waste is co-incinerated with municipal solid fuels and wastes of different composition. This co entails increased production emissions such as CO (carbon monoxide), NOx (nitrogen oxides), particulate matter (particulate matter), PM10, HCl (hydrogen chloride), PCDD/F (polychlorinated dibenzodioxins and dibenzofurans), PCBs (polychlorinated biphenyls) and others. The experiment was focused on the emission factors from the combustion of fossil fuels in combination with municipal waste in conventional boilers designed to burn solid fuel.

  11. Development of an Air-Source Heat Pump Integrated with a Water Heating / Dehumidification Module

    Energy Technology Data Exchange (ETDEWEB)

    Rice, C Keith [ORNL; Uselton, Robert B. [Lennox Industries, Inc; Shen, Bo [ORNL; Baxter, Van D [ORNL; Shrestha, Som S [ORNL

    2014-01-01

    A residential-sized dual air-source integrated heat pump (AS-IHP) concept is under development in partnership between ORNL and a manufacturer. The concept design consists of a two-stage air-source heat pump (ASHP) coupled on the air distribution side with a separate novel water heating/dehumidification (WH/DH) module. The motivation for this unusual equipment combination is the forecast trend for home sensible loads to be reduced more than latent loads. Integration of water heating with a space dehumidification cycle addresses humidity control while performing double-duty. This approach can be applied to retrofit/upgrade applications as well as new construction. A WH/DH module capable of ~1.47 L/h water removal and ~2 kW water heating capacity was assembled by the manufacturer. A heat pump system model was used to guide the controls design; lab testing was conducted and used to calibrate the models. Performance maps were generated and used in a TRNSYS sub-hourly simulation to predict annual performance in a well-insulated house. Annual HVAC/WH energy savings of ~35% are predicted in cold and hot-humid U.S. climates compared to a minimum efficiency baseline.

  12. Economic and safety aspects of using moderator heat for feed water heating in a nuclear power plant

    International Nuclear Information System (INIS)

    Patwegar, I.A.; Dutta, Anu; Chaki, S.K.; Venkat Raj, V.

    2002-01-01

    Full text: In the proposed advanced heavy water reactor (AHWR), coolant and moderator are separated by the coolant channel. The coolant absorbs most of the fission heat produced in the reactor core. However, the moderator absorbs about 5 to 6 % of the fission heat. In a reactor producing 750 MW(th) power, this moderator heat is about 40 MW. In the present Indian PHWR (pressurized heavy water reactor) systems, this moderator heat is lost to a sink through the moderator heat exchangers, which are cooled by process water. This paper presents the results of the steam cycle analysis carried out for AHWR using moderator heat exchangers as part of the feed heating system. The present study is an attempt to determine the gain in electrical output (MW) if moderator heat is utilized for feed water heating. The operational and safety aspects of using moderator heat are also discussed in the paper

  13. A comprehensive examination of heat transfer correlations suitable for reactor safety analysis

    International Nuclear Information System (INIS)

    Groeneveld, D.C.; Snoek, C.W.

    1986-01-01

    Due to the inadequate understanding of heat transfer mechanisms, an empirical approach is often necessary. This approach requires the derivation of empirical heat transfer correlations for each heat transfer configuration, resulting in numerous correlations for each heat transfer mode. A simplification that is frequently used is to combine these heat transfer correlations using some suitably defined local parameters to characterize the heat transfer process. These local condition correlations, usually encountered in reactor safety codes are discussed in this paper

  14. North Village Ground Source Heat Pump Demonstration Project

    Energy Technology Data Exchange (ETDEWEB)

    Redderson, Jeff

    2015-08-03

    This project demonstrated the feasibility of converting from a traditional direct exchange system to a ground source heat pump system on a large scale, multiple building apartment complex on a university campus. A total of ten apartment buildings were converted using vertical well fields and a ground source loop that connected the 24 apartments in each building into a common system. The system has yielded significant operational savings in both energy and maintenance and transformed the living environments of these residential buildings for our students.

  15. Heat source component development program, October 1977--February 1978

    International Nuclear Information System (INIS)

    1978-03-01

    The General Purpose Heat Source (GPHS) is being developed by Los Alamos Scientific Laboratory (LASL) for the Department of Energy (DOE) Division of Nuclear Research and Application (DNRA). The first mission scheduled for the GPHS is the NASA Out-of-Ecliptic Flight in January, 1983. During the current reporting period (October--December, 1977, January--February, 1978), activities in this task were conducted as follows: (1) documentation of results of the reentry thermal, ablation, and thermal stress analyses of the conceptual designs; (2) identification and completion of modifications to the thermal and ablation models used to determine the performance response of the heat source modules during reentry; (3) initiation of modifications to the thermal stress model used to determine the performance response of heat source modules during reentry; (4) completion and documentation of the surface chemistry experiments; (5) initiation and completion of activities in support of LASL to define test plans for the trial design phase of the GPHS development program; (6) participation in the GPHS design review meeting held at DOE/Germantown, Maryland, December 19--20, 1977; and (7) initiation of the thermal analysis of Trial Design 1.1

  16. Increase of COP for heat transformer in water purification systems. Part I - Increasing heat source temperature

    International Nuclear Information System (INIS)

    Siqueiros, J.; Romero, R.J.

    2007-01-01

    The integration of a water purification system in a heat transformer allows a fraction of heat obtained by the heat transformer to be recycled, increasing the heat source temperature. Consequently, the evaporator and generator temperatures are also increased. For any operating conditions, keeping the condenser and absorber temperatures and also the heat load to the evaporator and generator, a higher value of COP is obtained when only the evaporator and generator temperatures are increased. Simulation with proven software compares the performance of the modeling of an absorption heat transformer for water purification (AHTWP) operating with water/lithium bromide, as the working fluid-absorbent pair. Plots of enthalpy-based coefficients of performance (COP ET ) and the increase in the coefficient of performance (COP) are shown against absorber temperature for several thermodynamic operating conditions. The results showed that proposed (AHTWP) system is capable of increasing the original value of COP ET more than 120%, by recycling part of the energy from a water purification system. The proposed system allows to increase COP values from any experimental data for water purification or any other distillation system integrated to a heat transformer, regardless of the actual COP value and any working fluid-absorbent pair

  17. Periodic inspection for safety of CANDU heat transport piping systems

    International Nuclear Information System (INIS)

    Ellyin, F.

    1979-10-01

    Periodic inspection of heat transport and emergency core cooling piping systems is intended to maintain an adequate level of safety throughout the life of the plant, and to protect plant personnel and the public from the consequences of a failure and release of fission products. This report outlines a rational approach to the periodic inspection based on a fully probabilistic model. It demonstrates the methodology based on theoretical treatment and experimental data whereby the strength of a pressurized pipe or vessel containing a defect could be evaluated. It also shows how the extension of the defect at various lifetimes could be predicted. These relationships are prerequisite for the probabilistic formulation and analysis for the periodic inspection of piping systems

  18. Towards a Future of District Heating Systems with Low-Temperature Operation together with Non-Fossil Fuel Heat Sources

    DEFF Research Database (Denmark)

    Tol, Hakan; Dinçer, Ibrahim; Svendsen, Svend

    2012-01-01

    This study focused on investigation of non-fossil fuel heat sources to be supplied to low-energy district heating systems operating in low temperature such as 55 C and 25 C in terms of, respectively, supply and return. Vast variety of heat sources classed in categories such as fossil fuel...

  19. Overview of physical safety of radiation sources in Brazil

    International Nuclear Information System (INIS)

    Lima, A.R.; Silva, F.C.A. da

    2017-01-01

    The threat of 'radiological terrorism' has been recognized worldwide after the event of September 11, 2001. Radioactive sources can be used for the development of DDR ('dirty bomb') devices. Studies show that the use of a DDR could cause health damage, psychosocial and economic and environmental damage. Brazil follows this worldwide concern, since it has a large medical-industrial park that uses radioactive sources. This paper presents an overview of the physical safety of radioactive sources in Brazil, based on the inventory of radiative facilities, regulatory aspects and international recommendations. For the preparation of the study, the database of radioactive sources of the regulatory body, the current normative status and the international recommendations were used. In Brazil there are approximately 2,500 radiative installations, with about 400 radioactive sources Category 1 and 2, which are the biggest concern in terms of physical safety. The Brazilian licensing standard addresses only some aspects of physical protection, not providing a clear orientation for the elaboration and implementation of physical protection systems, in accordance with international recommendations. For Brazil to be included in the world scenario of physical safety of radioactive sources, it is urgent to elaborate specific legislation with well-defined regulatory criteria. The lack of more detailed requirements makes it difficult to make a more careful regulatory assessment of the physical protection conditions of the facilities, either through the evaluation of plans and other physical protection documents or through regulatory inspections

  20. USA perspectives. Safety and security of radioactive sources

    International Nuclear Information System (INIS)

    Dicus, G.J.

    1999-01-01

    In contrast to the 103 licensed nuclear power plants in the United States, there are about 157,000 licenses that authorize the use of radioactive materials subject to US Atomic Energy Act. as amended. Each year the NRC receives about 200 reports of lost, stolen or abandoned radioactive sources and devices. The NRC has established a programme to review and analyze reports and other information on losses, thefts, abandonments, and discoveries of radioactive sources that helped to identify and characterize the problem with safety and security of radioactive sources in devices used under the general license programme. In summary, a large number of radioactive sources in use in the USA have a very good safety record. When used properly by trained personnel with effective regulatory oversight, the many uses of radioactive sources are safe and provide a net benefit to society. If problems occur such as overexposures or contamination of property, it is essential that hey are promptly reported to the regulatory authority. If necessary appropriate emergency response measures can be taken, and the problems analysed. In that way, effective risk-informed regulatory measures can be activated to assure the continued safety and security of radioactive sources

  1. Radiation protection and safety of radiation sources international basic safety standards

    CERN Document Server

    International Atomic Energy Agency. Vienna

    2014-01-01

    The Board of Governors of the IAEA first approved Basic Safety Standards in June 1962; they were published by the IAEA as IAEA Safety Series No. 9. A revised edition was issued in 1967. A third revision was published by the IAEA as the 1982 Edition of IAEA Safety Series No. 9 ; this edition was jointly sponsored by the IAEA, ILO, OECD/NEA and the WHO. The next edition was International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources, published by the IAEA as IAEA Safety Series No. 115 in February 1996, and jointly sponsored by the FAO, IAEA, ILO, OECD/NEA, PAHO and the WHO.

  2. Thulium heat source for high-endurance and high-energy density power systems

    International Nuclear Information System (INIS)

    Walter, C.E.; Kammeraad, J.E.; Van Konynenburg, R.; VanSant, J.H.

    1991-05-01

    We are studying the performance characteristics of radioisotope heat source designs for high-endurance and high-energy-density power systems that use thulium-170. Heat sources in the power range of 5--50 kW th coupled with a power conversion efficiency of ∼30%, can easily satisfy current missions for autonomous underwater vehicles. New naval missions will be possible because thulium isotope power systems have a factor of one-to-two hundred higher endurance and energy density than chemical and electrochemical systems. Thulium-170 also has several other attractive features, including the fact that it decays to stable ytterbium-170 with a half-life of four months. For terrestrial applications, refueling on that time scale should be acceptable in view of the advantage of its benign decay. The heat source designs we are studying account for the requirements of isotope production, shielding, and integration with power conversion components. These requirements are driven by environmental and safety considerations. Thulium is present in the form of thin refractory thulia disks that allow power conversion at high peak temperature. We give estimates of power system state points, performance, mass, and volume characteristics. Monte Carlo radiation analysis provides a detailed assessment of shield requirements and heat transfer under normal and distressed conditions is also considered. 11 refs., 7 figs., 4 tabs

  3. The advanced neutron source safety approach and plans

    International Nuclear Information System (INIS)

    Harrington, R.M.

    1989-01-01

    The Advanced Neutron Source (ANS) is a user facility for all areas of neutron research proposed for construction at the Oak Ridge National Laboratory. The neutron source is planned to be a 350-MW research reactor. The reactor, currently in conceptual design, will belong to the United States Department of Energy (USDOE). The safety approach and planned elements of the safety program for the ANS are described. The safety approach is to incorporate USDOE requirements [which, by reference, include appropriate requirements from the United States Nuclear Regulatory Commission (USNRC) and other national and state regulatory agencies] into the design, and to utilize probabilistic risk assessment (PRA) techniques during design to achieve extremely low probability of severe core damage. The PRA has already begun and will continue throughout the design and construction of the reactor. Computer analyses will be conducted for a complete spectrum of accidental events, from anticipated events to very infrequent occurrences. 8 refs., 2 tabs

  4. The Advanced Neutron Source safety approach and plans

    International Nuclear Information System (INIS)

    Harrington, R.M.

    1990-01-01

    The Advanced Neutron Source (ANS) is a user facility proposed for construction at the Oak Ridge National Laboratory for all areas of neutron research. The neutron source is planned to be a 350-MW research reactor. The reactor, currently in conceptual design, will belong to the United States Department of Energy (USDOE). The safety approach and planned elements of the safety program for the ANS are described. The safety approach is to incorporate USDOE requirements (which, by reference, include appropriate requirements from the United States Nuclear Regulatory Commission (USNRC) and other national and state regulatory agencies) into the design, and to utilize probabilistic risk assessment (PRA) techniques during design to achieve extremely low probability of severe core damage. The PRA has already begun and will continue throughout the design and construction of the reactor. Computer analyses will be conducted for a complete spectrum of accidental events, from anticipated events to very infrequent occurrences

  5. The technological safety in facilities that manage radioactive sources

    International Nuclear Information System (INIS)

    Lizcano, D.

    2014-10-01

    The sealed radioactive sources are used inside a wide range of applications in the medicine, industry and investigation around the world. These sources can contain a great radionuclides variety, exhibiting a wide spectrum of activities and radiological half lives. This way, we can find pattern sources of radionuclides as Americium-241, Plutonium-238, Plutonium-239, Thorium-228 and Thorium-230, etc., with some activity of kBq in research laboratories, Iridium-192 and Cesium-137 sources used in brachytherapy with GBq activities, until sources with P Bq activities in industrial irradiators of Cobalt-60 and Cesium-137. This document approach the physical safety that entities like the IAEA recommends for the facilities that contain sealed sources, especially the measures that are taking in the Instituto Nacional de Investigaciones Nucleares (ININ) and others government facilities. (Author)

  6. A key review of wastewater source heat pump (WWSHP) systems

    International Nuclear Information System (INIS)

    Hepbasli, Arif; Biyik, Emrah; Ekren, Orhan; Gunerhan, Huseyin; Araz, Mustafa

    2014-01-01

    Highlights: • Comprehensively reviewing WWSHP systems for the first time. • Varying the COP values for heating of the reviewed systems between 1.77 and 10.63. • Ranging the COP values for cooling of the reviewed systems from 2.23 to 5.35. • Being the majority of the performance assessments on the energetic basis. - Abstract: Heat pumps (HPs) are part of the environmentally friendly technologies using renewable energy and have been utilized in the developed countries for years. Wastewater is seen as a renewable heat source for HPs. At the beginning of the 1980s, waste (sewage) water source heat pumps (WWSHPs) were widely applied in North European countries like Sweden and Norway and partially applied in China. In the past two decades, the WWSHP has become increasingly popular due to its advantages of relatively higher energy utilization efficiency and environmental protection. The present study comprehensively reviews WWSHP systems in terms of applications and performance assessments including energetic, exergetic, environmental and economic aspects for the first time to the best of the authors’ knowledge. In this context, a historical development of WWSHPs was briefly given first. Next, wastewater potential and its characteristics were presented while a WWSHP system was introduced. The previously conducted studies on WWSHPs were then reviewed and classified in a tabulated form. Finally, some concluding remarks were listed. The COP values of the reviewed studies ranged from 1.77 to 10.63 for heating and 2.23 to 5.35 for cooling based on the experimental and simulated values. The performance assessments are mostly made using energy analysis methods while the number of exergetic evaluations is very low and has not been comprehensively performed. It is expected that the comprehensive review here will be very beneficial to those dealing with the design, analysis, simulation and performance assessment of WWSHP systems

  7. Heat sources for heat pumps in the energetic and economic comparison; Waermequellen fuer Waermepumpen im energetischen und wirtschaftlichen Vergleich

    Energy Technology Data Exchange (ETDEWEB)

    Bockelmann, Franziska; Fisch, M. Norbert; Schlosser, Mathias; Peter, Markus [Technische Univ. Braunschweig (Germany). Inst. fuer Gebaeude- und Solartechnik

    2016-07-01

    Because of the growing application of heat pumps also the number of potentially usable low-temperature heat sources and corresponding heat exchangers for heat-pump systems present in the market increases. Thereby products like energy fences, high-power piles, ore ice reservoir come into applications without any knowledge ab out their power or the cost-profit ratio. The optimized lay-out of the coupling to the building are however essential conditions in order to reach an energy-efficient and durable operation of the facilities. The research project ''future heat pump'' sponsored by the BMWi is dedicated to the energetic and economic evaluation of heat sources for heat pumps. In this connection a pre-check-tool for the preliminary selection of low-temperature heat sources and connected, suitable heat-exchange systems is developed and their actual status of development presented. The holistic, comparing consideration of the different heat sources and heat-exchanger systems is related among others to the power numbers of the heat pumps, the entry and withdrawal services of the heat-exchangers, and the general performance of the systems. Additionally an estimation of economic and ecologic aspects (investment and operation costs, CO{sub 2} emissions) is made. Aim is the determination of the plausibility of applications and essential boundary conditions of single source systems. For the qualitative comparison in a project-accompanying monitoring different facilities and source systems are measurement-technically comprehended.

  8. Heat transfer within a concrete slab with a finite microwave heating source

    International Nuclear Information System (INIS)

    Lagos, L.E.; Li, W.; Ebadian, M.A.; Grubb, R.G.

    1995-01-01

    In the present paper, the concrete decontamination and decommissioning process with a finite microwave heating source is investigated theoretically. For the microwave induced heating pattern, a multilayer concrete slab, which includes steel reinforcement mesh, is assumed to be exposed to a finite plane microwave source at normal incidence. Two-dimensional heat transport within the concrete is also considered to evaluate the variations of temperature with heating time at different frequencies with and without the presence of the reinforcement bars. Four commonly used industrial microwave frequencies of 0.896, 2.45, 10.6 and 18.0 GHz have been selected. The results revealed that as the microwave frequency increases to, or higher than 10.6 GHz, the maximum temperature shifts toward the front surface of the concrete. It was found that the presence of a steel reinforcement mesh causes part of the microwave energy to be blocked and reflected. Furthermore, it was observed that the temperature distribution is nearly uniform within the dimensions of the microwave applicator for a high microwave power intensity and a short heating time. (author)

  9. Soil temperature distribution around a U-tube heat exchanger in a multi-function ground source heat pump system

    International Nuclear Information System (INIS)

    Li Shuhong; Yang Weihua; Zhang Xiaosong

    2009-01-01

    The imbalance of heat extracted from the earth by the underground heat exchangers in winter and ejected into it in summer is expected to affect the long term performance of conventional ground source heat pump (GSHP) in territories with a cold winter and a warm summer such as the middle and downstream areas of the Yangtze River in China. This paper presents a new multi-function ground source heat pump (MFGSHP) system which supplies hot water as well as space cooling/heating to mitigate the soil imbalance of the extracted and ejected heat by a ground source heat pump system. The heat transfer characteristic is studied and the soil temperature around the underground heat exchangers are simulated under a typical climatic condition of the Yangtze River. A three-dimensional model was constructed with the commercial computational fluid dynamics software FLUENT based on the inner heat source theory. Temperature distribution and variation trend of a tube cluster of the underground heat exchanger are simulated for the long term performance. The results show that the soil temperature around the underground tube keeps increasing due to the surplus heat ejected into the earth in summer, which deteriorates the system performance and may lead to the eventual system deterioration. The simulation shows that MFGSHP can effectively alleviate the temperature rise by balancing the heat ejected to/extracted from underground by the conventional ground source heat pump system. The new system also improves the energy efficiency.

  10. International basic safety standards for protecting against ionizing radiation and for the safety of radiation sources

    International Nuclear Information System (INIS)

    1997-01-01

    The purpose of the Standards is to establish basic requirements for protection against the risks associated with exposure to ionizing radiation (hereinafter termed radiation) and for the safety of radiation sources that may deliver such exposure. The Standards have been developed from widely accepted radiation protection and safety principles, such as those published in the Annals of the ICRP and the IAEA Safety Series. They are intended to ensure the safety of all types of radiation sources and, in doing so, to complement standards already developed for large and complex radiation sources, such as nuclear reactors and radioactive waste management facilities. For the sources, more specific standards, such as those issued by the IAEA, are typically needed to achieve acceptable levels of safety. As these more specific standards are generally consistent with the Standards, in complying with them, such more complex installations will also generally comply with the Standards. The Standards are limited to specifying basic requirements of radiation protection and safety, with some guidance on how to apply them. General guidance on applying some of the requirements is available in the publications of the Sponsoring Organizations and additional guidance will be developed as needed in the light of experience gained in the application of the Standards

  11. International basic safety standards for protecting against ionizing radiation and for the safety of radiation sources

    International Nuclear Information System (INIS)

    1996-01-01

    The purpose of the Standards is to establish basic requirements for protection against the risks associated with exposure to ionizing radiation (hereinafter termed radiation) and for the safety of radiation sources that may deliver such exposure. The Standards have been developed from widely accepted radiation protection and safety principles, such as those published in the Annals of the ICRP and the IAEA Safety Series. They are intended to ensure the safety of all types of radiation sources and, in doing so, to complement standards already developed for large and complex radiation sources, such as nuclear reactors and radioactive waste management facilities. For the sources, more specific standards, such as those issued by the IAEA, are typically needed to achieve acceptable levels of safety. As these more specific standards are generally consistent with the Standards, in complying with them, such more complex installations will also generally comply with the Standards. The Standards are limited to specifying basic requirements of radiation protection and safety, with some guidance on how to apply them. General guidance on applying some of the requirements is available in the publications of the Sponsoring Organizations and additional guidance will be developed as needed in the light of experience gained in the application of the Standards. Tabs

  12. Hybrid ground-source heat pump system with active air source regeneration

    International Nuclear Information System (INIS)

    Allaerts, K.; Coomans, M.; Salenbien, R.

    2015-01-01

    Highlights: • A hybrid ground source heat pump system with two separate borefields is modelled. • The maximum underground storage temperature depends on the size of the drycooler. • Drycooler selection curves are given as function of underground storage temperature. • The size of the cold storage is reduced with 47% in the cost optimal configuration. • The cooling seasonal performance factor decreases with reduced storage capacity. - Abstract: Ground-source heat pump systems (GSHP) offer great advantages over traditional heating and cooling installations. However, their applications are limited due to the high initial costs of borehole drilling. One way to avoid these costs is by reducing the size of the borefield, e.g. by combining the system with other renewable energy sources or by using active regeneration to increase the system efficiency. In this paper a hybrid ground-source heat pump system (HGSHP) is analyzed. The borefield is split into a warm part and a cold part, which allows for seasonal thermal-energy storage. Additionally, supplementary drycoolers capture heat during summer and cold during winter. The relationship between the underground storage size and temperature and the drycooler capacity is described, using an office building in Flanders (Belgium) as reference case. Results show that with a HGSHP system a significant borefield size reduction can be achieved without compromising system performance; i.e. for the reference case a reduction of 47% was achieved in the cost-optimal configuration. It is also shown that the cooling seasonal performance factor decreases significantly with underground storage capacity. In addition, the HGSHP can be used to maintain or restore thermal balance in the geothermal source when heating and cooling loads do not match

  13. Safety of radiation sources and other radioactive materials in Jordan

    International Nuclear Information System (INIS)

    Majali, M.M.

    2001-01-01

    Since joining the IAEA Model Project for upgrading radiation protection infrastructure in countries of West Asia, Jordan has amended its radiation safety legislation. The Regulatory Authority is improving its inventory system for radiation sources and other radioactive materials and also its notification, registration, licensing, inspection and enforcement systems. It has established national provisions for the management of orphan sources after they have been found. The system for the control of the radiation sources and other radioactive materials entering the country has been improved by the Regulatory Authority. (author)

  14. Safety Framework for Nuclear Power Source Applications in Outer Space

    International Nuclear Information System (INIS)

    2009-01-01

    Nuclear power sources (NPS) for use in outer space have been developed and used in space applications where unique mission requirements and constraints on electrical power and thermal management precluded the use of non-nuclear power sources. Such missions have included interplanetary missions to the outer limits of the Solar System, for which solar panels were not suitable as a source of electrical power because of the long duration of these missions at great distances from the Sun. According to current knowledge and capabilities, space NPS are the only viable energy option to power some space missions and significantly enhance others. Several ongoing and foreseeable missions would not be possible without the use of space NPS. Past, present and foreseeable space NPS applications include radioisotope power systems (for example, radioisotope thermoelectric generators and radioisotope heater units) and nuclear reactor systems for power and propulsion. The presence of radioactive materials or nuclear fuels in space NPS and their consequent potential for harm to people and the environment in Earth's biosphere due to an accident require that safety should always be an inherent part of the design and application of space NPS. NPS applications in outer space have unique safety considerations compared with terrestrial applications. Unlike many terrestrial nuclear applications, space applications tend to be used infrequently and their requirements can vary significantly depending upon the specific mission. Mission launch and outer space operational requirements impose size, mass and other space environment limitations not present for many terrestrial nuclear facilities. For some applications, space NPS must operate autonomously at great distances from Earth in harsh environments. Potential accident conditions resulting from launch failures and inadvertent re-entry could expose NPS to extreme physical conditions. These and other unique safety considerations for the use of

  15. Experimental investigation and feasibility analysis on a capillary radiant heating system based on solar and air source heat pump dual heat source

    International Nuclear Information System (INIS)

    Zhao, M.; Gu, Z.L.; Kang, W.B.; Liu, X.; Zhang, L.Y.; Jin, L.W.; Zhang, Q.L.

    2017-01-01

    Graphical abstract: (a) Vertical temperature gradient in Case 3, (b) PMV and PPD of the test room in Case 3, (c) operating time of SPCTS and ASHP systems in Case 3 and (d) the proportion of SPCTS operating time. - Highlights: • A capillary heating system based on solar and air source heat pump was developed. • Influence of supply water temperature on solar energy saving rate was investigated. • Heating performance and thermal comfort of capillary heating system were analyzed. • Low temperature heating with capillary is suitable for solar heating system. - Abstract: Due to sustainable development, solar energy has drawn much attention and been widely applied in buildings. However, the application of solar energy is limited because of its instability, intermittency and low energy density in winter. In order to use low density and instable solar energy source for heating and improve the utilization efficiency of solar energy, a solar phase change thermal storage (SPCTS) heating system using a radiant-capillary-terminal (RCT) to effectively match the low temperature hot water, a phase change thermal storage (PCTS) to store and continuously utilize the solar energy, and an air source heat pump (ASHP) as an alternate energy, was proposed and set up in this research. Series of experiments were conducted to obtain the relation between the solar radiation utilization rate and the heating supply temperatures, and to evaluate the performance of the RCT module and the indoor thermal environment of the system for its practical application in a residential building in the north-western City of Xi’an, China. The results show that energy saving of the solar heating system can be significantly improved by reducing the supplied water temperature, and the supplied water temperature of the RCT would be no more than 35 °C. The capillary radiation heating can adopt a lower water temperature and create a good thermal comfort environment as well. These results may lead to the

  16. Ground-source heat pump case studies and utility programs

    Energy Technology Data Exchange (ETDEWEB)

    Lienau, P.J.; Boyd, T.L.; Rogers, R.L.

    1995-04-01

    Ground-source heat pump systems are one of the promising new energy technologies that has shown rapid increase in usage over the past ten years in the United States. These systems offer substantial benefits to consumers and utilities in energy (kWh) and demand (kW) savings. The purpose of this study was to determine what existing monitored data was available mainly from electric utilities on heat pump performance, energy savings and demand reduction for residential, school and commercial building applications. In order to verify the performance, information was collected for 253 case studies from mainly utilities throughout the United States. The case studies were compiled into a database. The database was organized into general information, system information, ground system information, system performance, and additional information. Information was developed on the status of demand-side management of ground-source heat pump programs for about 60 electric utility and rural electric cooperatives on marketing, incentive programs, barriers to market penetration, number units installed in service area, and benefits.

  17. Electron beam welding of iridium heat source capsules

    International Nuclear Information System (INIS)

    Mustaleski, T.M.; Yearwood, J.C.; Burgan, C.E.; Green, L.A.

    1991-01-01

    The development of the welding procedures for the production of DOP-26 iridium alloy cups for heat source encapsulation is described. All the final assembly welds were made using the electron beam welding process. The welding of the 0.13-mm weld shield required the use of computer controlled X-Y table and a run-off tab. Welding of the frit vent to the cup required that a laser weld be made to hold the frit assembly edges together for the final electron beam weld. Great care is required in tooling design and beam placement to achieve acceptable results. Unsuccessful attempts to use laser beam welding for heat shield butt weld are discussed

  18. HTGR nuclear heat source component design and experience

    International Nuclear Information System (INIS)

    Peinado, C.O.; Wunderlich, R.G.; Simon, W.A.

    1982-05-01

    The high-temperature gas-cooled reactor (HTGR) nuclear heat source components have been under design and development since the mid-1950's. Two power plants have been designed, constructed, and operated: the Peach Bottom Atomic Power Station and the Fort St. Vrain Nuclear Generating Station. Recently, development has focused on the primary system components for a 2240-MW(t) steam cycle HTGR capable of generating about 900 MW(e) electric power or alternately producing high-grade steam and cogenerating electric power. These components include the steam generators, core auxiliary heat exchangers, primary and auxiliary circulators, reactor internals, and thermal barrier system. A discussion of the design and operating experience of these components is included

  19. Regulatory Control of Radiation Sources. Safety Guide (Arabic Edition)

    International Nuclear Information System (INIS)

    2012-01-01

    This Safety Guide is intended to assist States in implementing the requirements established in Safety Standards Series No. GS-R-1, Legal and Governmental Infrastructure for Nuclear, Radiation, Radioactive Waste and Transport Safety, for a national regulatory infrastructure to regulate any practice involving radiation sources in medicine, industry, research, agriculture and education. The Safety Guide provides advice on the legislative basis for establishing regulatory bodies, including the effective independence of the regulatory body. It also provides guidance on implementing the functions and activities of regulatory bodies: the development of regulations and guides on radiation safety; implementation of a system for notification and authorization; carrying out regulatory inspections; taking necessary enforcement actions; and investigating accidents and circumstances potentially giving rise to accidents. The various aspects relating to the regulatory control of consumer products are explained, including justification, optimization of exposure, safety assessment and authorization. Guidance is also provided on the organization and staffing of regulatory bodies. Contents: 1. Introduction; 2. Legal framework for a regulatory infrastructure; 3. Principal functions and activities of the regulatory body; 4. Regulatory control of the supply of consumer products; 5. Functions of the regulatory body shared with other governmental agencies; 6. Organization and staffing of the regulatory body; 7. Documentation of the functions and activities of the regulatory body; 8. Support services; 9. Quality management for the regulatory system.

  20. Quality assurance program plan for FRG sealed isotopic heat sources project (C-229)

    International Nuclear Information System (INIS)

    Tanke, J.M.

    1997-01-01

    This QAPP implements the Quality Assurance Program Plan for the FRG Sealed Isotopic Heat Sources Project (C-229). The heat source will be relocated from the 324 Building and placed in interim storage at the Central Waste Complex (CWC)

  1. Air source absorption heat pump in district heating: Applicability analysis and improvement options

    International Nuclear Information System (INIS)

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

    2015-01-01

    Highlights: • Applicability of air source absorption heat pump (ASAHP) district heating is studied. • Return temperature and energy saving rate (ESR) in various conditions are optimized. • ASAHP is more suitable for shorter distance or lower temperature district heating. • Two options can reduce the primary return temperature and improve the applicability. • The maximum ESR is improved from 13.6% to 20.4–25.6% by compression-assisted ASAHP. - Abstract: The low-temperature district heating system based on the air source absorption heat pump (ASAHP) was assessed to have great energy saving potential. However, this system may require smaller temperature drop leading to higher pump consumption for long-distance distribution. Therefore, the applicability of ASAHP-based district heating system is analyzed for different primary return temperatures, pipeline distances, pipeline resistances, supplied water temperatures, application regions, and working fluids. The energy saving rate (ESR) under different conditions are calculated, considering both the ASAHP efficiency and the distribution consumption. Results show that ASAHP system is more suitable for short-distance district heating, while for longer-distance heating, lower supplied hot water temperature is preferred. In addition, the advantages of NH 3 /H 2 O are inferior to those of NH 3 /LiNO 3 , and the advantages for warmer regions and lower pipeline resistance are more obvious. The primary return temperatures are optimized to obtain maximum ESRs, after which the suitable distances under different acceptable ESRs are summarized. To improve the applicability of ASAHP, the integration of cascaded heat exchanger (CHX) and compression-assisted ASAHP (CASAHP) are proposed, which can reduce the primary return temperature. The integration of CHX can effectively improve the applicability of ASAHP under higher supplied water temperatures. As for the utilization of CASAHP, higher compression ratio (CR) is better in

  2. Romanian experience on safety and security of radiation sources

    International Nuclear Information System (INIS)

    Botgros, Madalina; Coroianu, Anton; Negreanu, Mircea

    2008-01-01

    Romania has established the first administrative structure for controlling the deployment of the nuclear activities in 1961 and the first Romanian nuclear law was published in 1974. In the present, it is in force the Law no. 111, published in 1996 and republished in 2003. Moreover, there are available facilities and services to the persons authorized to manage radioactive sources. The regulation for safety and security of radioactive sources was amended two times in order to implement the international recommendations for setting up the national system for accounting and control of radiation sources and to coordinate the recovery activities. As part of national control programme, the national inventory of sources and devices is updated permanently, when issuing a new authorization, when modifying an existing one, or when renewing an authorization system and records in the database. The government responsibility for the orphan sources is stated in the law on radioactive waste management and decommissioning fund. There is a protocol between CNCAN, Ministry of Internal and Ministry of Health and Family regarding the co-operation in the case of finding orphan sources. When a radiation source is spent, it becomes radioactive waste that has to be disposed off properly. Depending on the case, the holder of a spent source has the possibility either to return the radioactive source to its manufacturer for regeneration or to transfer it to the Radioactive Waste Treatment Facility. (author)

  3. General-purpose heat source development. Phase II: conceptual designs

    International Nuclear Information System (INIS)

    Snow, E.C.; Zocher, R.W.; Grinberg, I.M.; Hulbert, L.E.

    1978-11-01

    Basic geometric module shapes and fuel arrays were studied to determine how well they could be expected to meet the General Purpose Heat Source (GPHS) design requirements. Seven conceptual designs were selected, detailed drawings produced, and these seven concepts analyzed. Three of these design concepts were selected as GPHS Trial Designs to be reanalyzed in more detail and tested. The geometric studies leading to the selection of the seven conceptual designs, the analyses of these designs, and the selection of the three trial designs are discussed

  4. 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.

  5. Effects of aqueous humor hydrodynamics on human eye heat transfer under external heat sources.

    Science.gov (United States)

    Tiang, Kor L; Ooi, Ean H

    2016-08-01

    The majority of the eye models developed in the late 90s and early 00s considers only heat conduction inside the eye. This assumption is not entirely correct, since the anterior and posterior chambers are filled aqueous humor (AH) that is constantly in motion due to thermally-induced buoyancy. In this paper, a three-dimensional model of the human eye is developed to investigate the effects AH hydrodynamics have on the human eye temperature under exposure to external heat sources. If the effects of AH flow are negligible, then future models can be developed without taking them into account, thus simplifying the modeling process. Two types of external thermal loads are considered; volumetric and surface irradiation. Results showed that heat convection due to AH flow contributes to nearly 95% of the total heat flow inside the anterior chamber. Moreover, the circulation inside the anterior chamber can cause an upward shift of the location of hotspot. This can have significant consequences to our understanding of heat-induced cataractogenesis. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

  6. Natural convection heat transfer in a rectangular pool with volumetric heat sources

    International Nuclear Information System (INIS)

    Lee, Seung Dong; Lee, Kang Hee; Suh, Kune Y.

    2003-01-01

    Natural convection plays an important role in determining the thermal load from debris accumulated in the reactor vessel lower head during a severe accident. The heat transfer within the molten core material can be characterized by buoyancy-induced flows resulting from internal heating due to decay of fission products. The thermo-fluid dynamic characteristics of the molten pool depend strongly on the thermal boundary conditions. The spatial and temporal variation of heat flux on the pool wall boundaries and the pool superheat are mainly characterized by the natural convection flow inside the molten pool. In general, natural convection involving internal heat generation is delineated in terms of the modified Rayleigh number, Ra', which quantifies the internal heat source and hence the strength of buoyancy. The test section is of rectangular cavity whose length, width, and height are 500 mm, 80 mm, and 250 mm, respectively. A total of twenty-four T-type thermocouples were installed in the test loop to measure temperature distribution. Four T-type thermocouples were utilized to measure temperatures on the boundary. A direct heating method was adopted in this test to simulate the uniform heat generation. The experiments covered a range of Rayleigh number, Ra, between 4.87x10 7 and 2.32x10 14 and Prandtl number, Pr, between 0.7 and 3.98. Tests were conducted with water and air as simulant. The upper and lower boundary conditions were maintained at a uniform temperature of 10degC. (author)

  7. Safety Analysis Report for Primary Capsule of Ir-192 Radiation Source

    International Nuclear Information System (INIS)

    Lee, J. C.; Bang, K. S.; Choi, W. S.; Seo, K. S.; Son, K. J.; Park, W. J.

    2008-12-01

    All of the source capsules to transport a special form radioactive material should be designed and fabricated in accordance with the design criteria prescribed in IAEA standards and domestic regulations. The objective of this project is to prove the safety of a primary capsule for Ir-192 radiation source which produced in the HANARO. The safety tests of primary capsules were carried out for the impact, percussion and heat conditions. And leakage tests were carried out before and after the each tests. The capsule showed slight scratches and their deformations were not found after each tests. It also met the allowable limits of leakage rate after each test. Therefore, it has been verified that the capsule was designed and fabricated to meet all requirements for the special form radioactive materials

  8. Start-up Characteristics of Swallow-tailed Axial-grooved Heat Pipe under the conditions of Multiple Heat Sources

    Science.gov (United States)

    Zhang, Renping

    2017-12-01

    A mathematical model was developed for predicting start-up characteristics of Swallow-tailed Axial-grooved Heat Pipe under the conditions of Multiple Heat Sources. The effects of heat capacitance of heat source, liquid-vapour interfacial evaporation-condensation heat transfer, shear stress at the interface was considered in current model. The interfacial evaporating mass flow rate is based on the kinetic analysis. Time variations of evaporating mass rate, wall temperature and liquid velocity are studied from the start-up to steady state. The calculated results show that wall temperature demonstrates step transition at the junction between the heat source and non-existent heat source on the evaporator. The liquid velocity changes drastically at the evaporator section, however, it has slight variation at the evaporator section without heat source. When the effect of heat source is ignored, the numerical temperature demonstrates a quicker response. With the consideration of capacitance of the heat source, the data obtained from the proposed model agree well with the experimental results.

  9. Ground source heat pump performance in case of high humidity soil and yearly balanced heat transfer

    International Nuclear Information System (INIS)

    Schibuola, Luigi; Tambani, Chiara; Zarrella, Angelo; Scarpa, Massimiliano

    2013-01-01

    Highlights: • GSHPs are simulated in case of humid soil and yearly balanced heat transfer. • Humid soil and yearly balanced heat transfer imply higher compactness of GSHPs. • Resulting GSHPs are compared with other traditional and innovative HVAC systems. • GSHPs score best, especially in case of inverter-driven compressors. - Abstract: Ground source heat pump (GSHP) systems are spreading also in Southern Europe, due to their high energy efficiency both in heating and in cooling mode. Moreover, they are particularly suitable in historical cities because of difficulties in the integration of heating/cooling systems into buildings subjected to historical preservation regulations. In these cases, GSHP systems, especially the ones provided with borehole heat exchangers, are a suitable solution instead of gas boilers, air-cooled chillers or cooling towers. In humid soils, GSHP systems are even more interesting because of their enhanced performance due to higher values of soil thermal conductivity and capacity. In this paper, GSHP systems operating under these boundary conditions are analyzed through a specific case study set in Venice and related to the restoration of an historical building. With this analysis the relevant influences of soil thermal conductivity and yearly balanced heat transfer in the design of the borehole field are shown. In particular, the paper shows the possibility to achieve higher compactness of the borehole field footprint area when yearly balanced heat transfer in the borehole field is expected. Then, the second set of results contained in the paper shows how GSHP systems designed for high humidity soils and yearly balanced heat loads at the ground side, even if characterized by a compact footprint area, may still ensure better performance than other available and more common technologies such as boilers, air-cooled chillers, chillers coupled with cooling towers and heat pumps and chillers coupled with lagoon water. As a consequence

  10. Heat buffers improve capacity and exploitation degree of geothermal energy sources

    NARCIS (Netherlands)

    Ooster, A.van t; Wit, J. de; Janssen, E.G.O.N.; Ruigrok, J.

    2008-01-01

    This research focuses on the role of heat buffers to support optimal use of combinations of traditional and renewable heat sources like geothermal heat for greenhouse heating. The objective was to determine the contribution of heat buffers to effective new combinations of resources that satisfy

  11. An Empirical Temperature Variance Source Model in Heated Jets

    Science.gov (United States)

    Khavaran, Abbas; Bridges, James

    2012-01-01

    An acoustic analogy approach is implemented that models the sources of jet noise in heated jets. The equivalent sources of turbulent mixing noise are recognized as the differences between the fluctuating and Favre-averaged Reynolds stresses and enthalpy fluxes. While in a conventional acoustic analogy only Reynolds stress components are scrutinized for their noise generation properties, it is now accepted that a comprehensive source model should include the additional entropy source term. Following Goldstein s generalized acoustic analogy, the set of Euler equations are divided into two sets of equations that govern a non-radiating base flow plus its residual components. When the base flow is considered as a locally parallel mean flow, the residual equations may be rearranged to form an inhomogeneous third-order wave equation. A general solution is written subsequently using a Green s function method while all non-linear terms are treated as the equivalent sources of aerodynamic sound and are modeled accordingly. In a previous study, a specialized Reynolds-averaged Navier-Stokes (RANS) solver was implemented to compute the variance of thermal fluctuations that determine the enthalpy flux source strength. The main objective here is to present an empirical model capable of providing a reasonable estimate of the stagnation temperature variance in a jet. Such a model is parameterized as a function of the mean stagnation temperature gradient in the jet, and is evaluated using commonly available RANS solvers. The ensuing thermal source distribution is compared with measurements as well as computational result from a dedicated RANS solver that employs an enthalpy variance and dissipation rate model. Turbulent mixing noise predictions are presented for a wide range of jet temperature ratios from 1.0 to 3.20.

  12. Design evolution and verification of the general-purpose heat source

    International Nuclear Information System (INIS)

    Schock, A.

    The General-Purpose Heat Source (GPHS) is a radioisotope heat source for use in space power systems. It employs a modular design, to make it adaptable to a wide range of energy conversion systems and power levels. Each 250 W module is completely autonomous, with its own passive safety provisions to prevent fuel release under all abort modes, including atmospheric reentry and earth impact. Prior development tests had demonstrated good impact survival as long as the iridium fuel capsules retained their ductility. This requires high impact temperatures, typically above 900 0 C and reasonably fine grain size, which in turn requires avoidance of excessive operating temperatures and reentry temperatures. These three requirements - on operating, reentry, and impact temperatures - are in mutual conflict, since thermal design changes to improve any one of these temperatures tend to worsen one or both of the others. This conflict creates a difficult design problem, which for a time threatened the success of the program. The present paper describes how this problem was overcome by successive design revisions, supplemented by thermal analyses and confirmatory vibration and impact tests; and how this may be achieved while raising the specific power of the GPHS to 83 W/lb, a 50% improvement over previously flown radioisotope heat sources

  13. Regulatory aspects of radiation sources safety in Albania

    International Nuclear Information System (INIS)

    Dollani, K.; Kushe, R.

    1998-01-01

    In this paper are presented the regulatory aspects of the radiation sources safety in Albania, based in the new Radiological Protection Act and Regulations. The radiation protection infrastructures and procedures are described as well as their functioning for the implementation of relevant activities such as licensing and regular inspection, personal dose monitoring, emergency preparedness which are developed in the frame of the IAEA Technical Co-operation Programme. The issue of the security of radiation sources is dealt in close relation with the preparation and use of the inventory of all radiation sources in the country. A special attention is paid to the identification and location of lost sources for their finding and secure storage. (author)

  14. Novel edible oil sources: Microwave heating and chemical properties.

    Science.gov (United States)

    Hashemi, Seyed Mohammad Bagher; Mousavi Khaneghah, Amin; Koubaa, Mohamed; Lopez-Cervantes, Jaime; Yousefabad, Seyed Hossein Asadi; Hosseini, Seyedeh Fatemeh; Karimi, Masoumeh; Motazedian, Azam; Asadifard, Samira

    2017-02-01

    The aim of this work was to investigate the effect of various microwave heating times (1, 3, 5, 10, and 15min) on the chemical properties of novel edible oil sources, including Mashhadi melon (Cucumis melo var. Iranians cv. Mashhadi), Iranian watermelon (Citrullus lanatus cv. Fire Fon), pumpkin (Cucurbita pepo subsp. pepo var. Styriaca), and yellow apple (Malus domestica cv. Golden Delicious) seed oils. The evaluated parameters were peroxide value (PV), conjugated diene (CD) and triene (CT) values, carbonyl value (CV), p-anisidine value (AnV), oil stability index (OSI), radical scavenging activity (RSA), total tocopherols, total phenolics, as well as chlorophyll and carotenoid contents. Results showed that extended microwave heating involves decreased quality of the seed oils, mainly due to the formation of primary and secondary oxidation products. Microwave heating time also affects the total contents of chlorophylls, carotenoids, phenolics and tocopherols, which clearly decrease by increasing the exposure time. The order of oxidative stability of the analyzed edible oils was pumpkin>Mashhadi melon>Iranian watermelon>yellow apple. The obtained results demonstrated the promising potential of these novel edible oils for different food applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. The safety and the security of radioactive sources

    International Nuclear Information System (INIS)

    Bhatt, B.C.; Ghosh, P.K.; Nandakumar, A.N.

    2003-01-01

    A Task Group was appointed by Chairman, AERB to review the current practice and recommend procedures for ensuring the Safety and the Security of Radioactive Sources in India. The Task Group identified the issues involved and concluded that the current regulatory procedure relating to licensing was adequate in view of the stress placed on pre-licensing requirements and the undertakings obtained from the licensee and ensuring that appropriate radiation monitors and trained personnel are available at the licensee's institution. Each licensee is required to submit periodic reports confiriming the safety and the security of the sources in the possession of the institution. It is important to conduct regulatory inspection of the institutions frequently. In order to optimise the regulatory effort involved, the report recommends frequencies of inspections commensurate with the potential hazard associated with the source. For this purpose the sources are brought under three categories which are largely based on the categorization recommended by the International Atomic Energy Agency (IAEA), Vienna with deviations introduced on the basis of rationalized hazard potential associated with the sources. The importance of technical coordination between AERB and BARC is emphasised. (author)

  16. Fission product source terms and engineered safety features

    International Nuclear Information System (INIS)

    Malinauskas, A.P.

    1984-01-01

    The author states that new, technically defensible, methodologies to establish realistic source term values for nuclear reactor accidents will soon be available. Although these methodologies will undoubtedly find widespread use in the development of accident response procedures, the author states that it is less clear that the industry is preparing to employ the newer results to develop a more rational approach to strategies for the mitigation of fission product releases. Questions concerning the performance of existing engineered safety systems are reviewed

  17. Radiation safety of sealed sources and equipment containing them

    International Nuclear Information System (INIS)

    1993-01-01

    The guide gives information and requirements concerning the technical construction, installation, use and licensing of devices containing sealed radioactive sources in order to ensure the operational safety. The requirements are in accordance with the international standards ISO 1677, ISO 2919, ISO 7205 and Nordic Recommendations on radiation protection for radionuclide gauges in permanent installation. The guide explains also the practical measures that must be taken into account when a radiation device is repaired, maintained or removed from the use. (8 refs.)

  18. National Synchrotron Light Source safety-analysis report

    International Nuclear Information System (INIS)

    Batchelor, K.

    1982-07-01

    This document covers all of the safety issues relating to the design and operation of the storage rings and injection system of the National Synchrotron Light Source. The building systems for fire protection, access and egress are described together with air and other gaseous control or venting systems. Details of shielding against prompt bremstrahlung radiation and synchrotron radiation are described and the administrative requirements to be satisfied for operation of a beam line at the facility are given

  19. Radiological safety of decayed source removal facility (DSRF) - an overview

    International Nuclear Information System (INIS)

    Rajput, Raksha; George, Jain Reji; Pathak, B.K.

    2018-01-01

    Industrial radiography is one of the major applications of radioisotope in engineering industry for Non-Destructive Testing (NDT). The equipment used for this purpose is called Industrial Radiography Exposure Device (IGRED) or radiography (RG) camera. In India, more than 1800 IGREDs including imported cameras are being used in NDT industry. These cameras are of different types and have various capacities to house different radioisotopes. Generally, 192 Ir sources are being used for NDT work. The sources are being supplied by BRIT to the users. After the useful period of the utilization of gamma intensity, the decayed source is returned to BRIT in RG camera. The decayed source is removed from the camera in the Decayed Source Removal Facility (DSRF). This facility serves the purpose of a miniature hot-cell with the capability of storing the decayed sources which are removed from the cameras. The empty camera is inspected for its mechanical functions and sent to BRIT's hot-cell for loading the new source. DSRF is situated at BRIT Vashi Complex. This paper deals with the radiological safety in the operation of DSRF for removing decayed sources from industrial radiography cameras

  20. Safety assessment plans for authorization and inspection of radiation sources

    International Nuclear Information System (INIS)

    2002-05-01

    The objective of this TECDOC is to enhance the efficacy, quality and efficiency of the whole regulatory process. It provides advice on good practice administrative procedures for the regulatory process for preparation of applications, granting of authorizations, inspection, and enforcement. It also provides information on the development and use of standard safety assessment plans for authorization and inspection. The plans are intended to be used in conjunction with more detailed advice related to specific practices. In this sense, this TECDOC provides advice on a systematic approach to evaluations of protection and safety while other IAEA Safety Guides assist the user to distinguish between the acceptable and the unacceptable. This TECDOC covers administrative advice to facilitate the regulatory process governing authorization and inspection. It also covers the use of standard assessment and inspection plans and provides simplified plans for the more common, well established uses of radiation sources in medicine and industry, i.e. sources for irradiation facilities, industrial radiography, well logging, industrial gauging, unsealed sources in industry, X ray diagnosis, nuclear medicine, teletherapy and brachytherapy

  1. Safety assessment plans for authorization and inspection of radiation sources

    International Nuclear Information System (INIS)

    1999-09-01

    The objective of this TECDOC is to enhance the efficacy, quality and efficiency of the whole regulatory process. It provides advice on good practice administrative procedures for the regulatory process for preparation of applications, granting of authorizations, inspection, and enforcement. It also provides information on the development and use of standard safety assessment plans for authorization and inspection. The plans are intended to be used in conjunction with more detailed advice related to specific practices. In this sense, this TECDOC provides advice on a systematic approach to evaluations of protection and safety while other IAEA Safety Guides assist the user to distinguish between the acceptable and the unacceptable. This TECDOC covers administrative advice to facilitate the regulatory process governing authorization and inspection. It also covers the use of standard assessment and inspection plans and provides simplified plans for the more common, well established uses of radiation sources in medicine and industry, i.e. sources for irradiation facilities, industrial radiography, well logging, industrial gauging, unsealed sources in industry, X ray diagnosis, nuclear medicine, teletherapy and brachytherapy

  2. Heat pump using dual heat sources of air and water. Performance with heat sources arranged in parallel; Mizu kuki ryonetsugen heat pump no kenkyu. Netsugen heiretsu unten ni okeru seino

    Energy Technology Data Exchange (ETDEWEB)

    Ito, S; Miura, N; Sato, S [Kanagawa Institute of Technology, Kanagawa (Japan); Uchikawa, Y; Hamada, K [Kubota Corp., Osaka (Japan)

    1996-10-27

    A heat pump system using water and air as heat sources was built and evaluated for its performance. In this system, evaporators may be operated singly or as connected in parallel or series, and, for each case, the quantity of heat acquired may be measured and system performance may be quantitatively evaluated. The findings follow. When the two heat sources are equal in temperature in the single-evaporator operation, the evaporation temperature is about 7{degree}C higher on the water side than on the air side, and the performance coefficient is about 0.7 higher. When the air heat source temperature is 25{degree}C in the parallel operation, like quantities of heat are obtained from both heat sources, and collection of heat from the water increases with a decrease in the air heat source temperature but, with an increase, collection from the air increases. When the air heat source temperature decreases, the evaporation temperature decreases in the single-evaporator working on the air and in the parallel operation but it levels off in the single-evaporator working on the water alone. When the water heat source temperature decreases, evaporation temperature drop is sharper in the single-evaporator working on the water than in the parallel operation, which suggests the transfer from the parallel operation to the single-evaporator working on the air. In the single-evaporator operation on the water heat source, the evaporation temperature linearly decreases with an increase in superheating. 1 ref., 10 figs.

  3. The encapsulated nuclear heat source reactor for proliferation-resistant nuclear energy

    International Nuclear Information System (INIS)

    Brown, N.W.; Hossain, Q.; Carelli, M.D.; Conway, L.; Dzodzo, M.; Greenspan, E.; Saphier, D.

    2001-01-01

    The encapsulated nuclear heat source (ENHS) is a modular reactor that was selected by the 1999 DOE NERI program as a candidate ''Generation-IV'' reactor concept. It is a fast neutron spectrum reactor cooled by Pb-Bi using natural circulation. It is designed for passive load following, for high level of passive safety, and for 15 years without refueling. One of the unique features of the ENHS is that the fission-generated heat is transferred from the primary coolant to the secondary coolant across the reactor vessel wall by conduction-providing for an essentially sealed module that is easy to install and replace. Because the fuel is encapsulated within a heavy steel container throughout its life it provides a unique improvement to the proliferation resistance of the nuclear fuel cycle. This paper presents the innovative technology of the ENHS. (author)

  4. The safety feature of hydraulic driving system of control rod for 200 MW nuclear heating reactor

    International Nuclear Information System (INIS)

    Chi Zongbo; Wu Yuanqiang

    1997-01-01

    The hydraulic driving system of control rod is used as control rod drive mechanism in 200 MW nuclear heating reactor. Design of this system is based on passive system, integrating drive and guide of control rod. The author analyzes the inherent safety and the design safety of this system, with mechanism of control rod not ejecting when the pressure of pressure vessel is lost, and calculating result of core not exposing when the amount of coolant is drained by broken pipe. The results indicate that this system has good safety feature, and assures reactor safety under any accident conditions, providing important technology support for 200 MW nuclear heating reactor with inherent safety feature

  5. Moving heat source in a confined channel: Heat transfer and boiling in endovenous laser ablation of varicose veins

    NARCIS (Netherlands)

    de Boer, Amit; Oliveira, Jorge L. G.; van der Geld, Cees W. M.; Malskat, Wendy S. J.; van den Bos, Renate; Nijsten, Tamar; van Gemert, Martin J. C.

    2017-01-01

    Motion of a moving laser light heat source in a confined volume has important applications such as in endovenous laser ablation (EVLA) of varicose veins. This light heats up the fluid and the wall volume by absorption and heat conduction. The present study compares the flow and temperature fields in

  6. Conjugated heat transfer of natural convection in pool with internal heat sources and convection in the tube

    International Nuclear Information System (INIS)

    Li Longjian; Liu Hongtao; Cui Wenzhi

    2007-01-01

    The conjugated heat transfer of natural convection in pool with internal heat source and the forced convection in the tube was analyzed, and the corresponding three-dimensional physical and mathematical model was proposed. A control volume based finite element method was employed to solve numerically the problem. The computations were performed for different internal heat source intensity of the pool and the different flow velocity in the tube. The computed heat transfer coefficients on the inner and outer wall showed well consistency of those calculated with the empirical correlations. Compared with the measured total heat transfer coefficients between the fluids in and out of the tube, the computed ones showed also the well consistency, which implied that the numerical model proposed in this paper was reliable. The research results revealed that the total heat transfer coefficients between the fluids were strongly affected by the internal heat source intensity of the pool liquid and the flow velocity in the tube. (authors)

  7. Heat pumps using vertical boreholls as heat source; Varmepumper med lodrette boringer som varmeoptager

    Energy Technology Data Exchange (ETDEWEB)

    Pedersen, Svend V. [Teknologisk Institut, Aarhus (Denmark); Thoegersen, L.; Soerensen, Inga [VIA University College, Risskov (Denmark)] [and others

    2013-01-15

    This report presents instructions on what to consider when you have to establish vertical wells as energy sources for ground source heating systems. The report provides an introduction into what to be aware of when it comes to sizing vertical ground hoses as heat absorbers for heat pumps. The initial geological assessments, you have to make are described and there are references to the available tools and websites that exist today. A calculation model is developed for the design of vertical ground hoses. This calculation model is intended as a tool for installers and consultants as well as well drillers. The calculation model contains two computational models, one can be used for initial calculations and dimensioning of vertical ground hoses, and the detailed model can be used for costing by well driller. The simple calculation is based on proven design approach from the German standard VDI 4640, and the detailed calculation is based on a known empirical calculation, which assumes that you know the geology in more detail. In the project measurements were carried out on four installations, and the calculations show that there is good agreement between the measurements and the calculation model. (LN)

  8. Heat input properties of hollow cathode arc as a welding heat source

    International Nuclear Information System (INIS)

    Nishikawa, Hiroshi; Shobako, Shinichiro; Ohta, Masashi; Ohji, Takayoshi

    2005-01-01

    In order to clarify whether a hollow cathode arc (HCA) can be used as a welding heat source in space, investigations into the fundamental characteristics of HCA were experimentally performed under low pressure conditions. The HCA method enables an arc discharge to ignite and maintain under low pressure conditions; in contrast, low pressure conditions make it extremely difficult for the conventional gas tungsten arc method to form an arc discharge. In an earlier paper, it was shown that the melting process by HCA is very sensitive to process parameters such as the gas flow rate and arc length, and a deep penetration forms when the arc length is long and the gas flow rate is low. In this paper, the distribution of the arc current on the anode surface and the plasma properties of the HCA under low pressure conditions have been made clear and the total heat energy to the anode has been discussed in order to understand the heat input properties of the HCA. The result shows that the HCA in the case of a low gas flow rate is a high and concentrated energy source, and the high energy input to the anode contributes to the deep penetration

  9. Ground Source Integrated Heat Pump (GS-IHP) Development

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, V. D. [ORNL; Rice, K. [ORNL; Murphy, R. [ORNL; Munk, J. [ORNL; Ally, Moonis [ORNL; Shen, Bo [ORNL; Craddick, William [ORNL; Hearn, Shawn A. [ClimateMaster, Inc.

    2013-05-24

    Between October 2008 and May 2013 ORNL and ClimateMaster, Inc. (CM) engaged in a Cooperative Research and Development Agreement (CRADA) to develop a groundsource integrated heat pump (GS-IHP) system for the US residential market. A initial prototype was designed and fabricated, lab-tested, and modeled in TRNSYS (SOLAR Energy Laboratory, et al, 2010) to predict annual performance relative to 1) a baseline suite of equipment meeting minimum efficiency standards in effect in 2006 (combination of air-source heat pump (ASHP) and resistance water heater) and 2) a state-of-the-art (SOA) two-capacity ground-source heat pump with desuperheater water heater (WH) option (GSHPwDS). Predicted total annual energy savings, while providing space conditioning and water heating for a 2600 ft{sup 2} (242 m{sup 2}) house at 5 U.S. locations, ranged from 52 to 59%, averaging 55%, relative to the minimum efficiency suite. Predicted energy use for water heating was reduced 68 to 78% relative to resistance WH. Predicted total annual savings for the GSHPwDS relative to the same baseline averaged 22.6% with water heating energy use reduced by 10 to 30% from desuperheater contributions. The 1st generation (or alpha) prototype design for the GS-IHP was finalized in 2010 and field test samples were fabricated for testing by CM and by ORNL. Two of the alpha units were installed in 3700 ft{sup 2} (345 m{sup 2}) houses at the ZEBRAlliance site in Oak Ridge and field tested during 2011. Based on the steady-state performance demonstrated by the GS-IHPs it was projected that it would achieve >52% energy savings relative to the minimum efficiency suite at this specific site. A number of operational issues with the alpha units were identified indicating design changes needed to the system before market introduction could be accomplished. These were communicated to CM throughout the field test period. Based on the alpha unit test results and the diagnostic information coming from the field test

  10. Design and safety aspects of the Cornell cold neutron source

    International Nuclear Information System (INIS)

    Ouellet, Carol G.; Clark, David D.

    1992-01-01

    The cold neutron beam facility at the Cornell University TRIGA Mark II reactor will begin operational testing in early 1993. It is designed to provide a low background subthermal neutron beam that is as free as possible of fast neutrons and gamma rays for applied research and graduate-level instruction. The Cornell cold neutron source differs from the more conventional types of cold sources in that it is inherently safer because it uses a safe handling material (mesitylene) as the moderator instead of hydrogen or methane, avoids the circulation of cryogenic fluids by removing heat from the system by conduction through a 99.99% pure copper rod attached to a cryogenic refrigerator, and is much smaller in its size and loads. The design details and potential hazards are described, where it is concluded that no credible accident involving the cold source could cause damage to the reactor or personnel, or cause release of radioactivity. (author)

  11. Nondestructive inspection of General Purpose Heat Source (GPHS) fueled clad girth welds

    International Nuclear Information System (INIS)

    Reimus, M. A. H.; George, T. G.; Lynch, C.; Padilla, M.; Moniz, P.; Guerrero, A.; Moyer, M. W.; Placr, A.

    1998-01-01

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of 238 Pu decay to an array of thermoelectric elements. The GPHS is fabricated using an iridium-alloy to contain the 238 PuO 2 fuel pellet. GPHS capsules will be utilized in the upcoming Cassini mission to explore Saturn and its moons. The physical integrity of the girth weld is important to mission safety and performance. Because past experience had revealed a potential for initiation of small cracks in the girth weld overlap zone, a nondestructive inspection of each capsule weld is required. An ultrasonic method was used to inspect the welds of capsules fabricated for the Galileo mission. The instrument, transducer, and method used were state of the art at the time (early 1980s). The ultrasonic instrumentation and methods used to inspect the Cassini GPHSs was significantly upgraded from those used for the Galileo mission. GPHSs that had ultrasonic reflectors in excess of the reject specification level were subsequently inspected with radiography to provide additional engineering data used to accept/reject the heat source. This paper describes the Galileo-era ultrasonic instrumentation and methods and the subsequent upgrades made to support testing of Cassini GPHSs. Also discussed is the data obtained from radiographic examination and correlation to ultrasonic examination results

  12. Nondestructive inspection of General Purpose Heat Source (GPHS) fueled clad girth welds

    International Nuclear Information System (INIS)

    Reimus, M.A.; George, T.G.; Lynch, C.; Padilla, M.; Moniz, P.; Guerrero, A.; Moyer, M.W.; Placr, A.

    1998-01-01

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of 238 Pu decay to an array of thermoelectric elements. The GPHS is fabricated using an iridium-alloy to contain the 238 PuO 2 fuel pellet. GPHS capsules will be utilized in the upcoming Cassini mission to explore Saturn and its moons. The physical integrity of the girth weld is important to mission safety and performance. Because past experience had revealed a potential for initiation of small cracks in the girth weld overlap zone, a nondestructive inspection of each capsule weld is required. An ultrasonic method was used to inspect the welds of capsules fabricated for the Galileo mission. The instrument, transducer, and method used were state of the art at the time (early 1980s). The ultrasonic instrumentation and methods used to inspect the Cassini GPHSs was significantly upgraded from those used for the Galileo mission. GPHSs that had ultrasonic reflectors in excess of the reject specification level were subsequently inspected with radiography to provide additional engineering data used to accept/reject the heat source. This paper describes the Galileo-era ultrasonic instrumentation and methods and the subsequent upgrades made to support testing of Cassini GPHSs. Also discussed is the data obtained from radiographic examination and correlation to ultrasonic examination results. copyright 1998 American Institute of Physics

  13. Tabulation of Fundamental Assembly Heat and Radiation Source Files

    International Nuclear Information System (INIS)

    T. deBues; J.C. Ryman

    2006-01-01

    The purpose of this calculation is to tabulate a set of computer files for use as input to the WPLOAD thermal loading software. These files contain details regarding heat and radiation from pressurized water reactor (PWR) assemblies and boiling water reactor (BWR) assemblies. The scope of this calculation is limited to rearranging and reducing the existing file information into a more streamlined set of tables for use as input to WPLOAD. The electronic source term files used as input to this calculation were generated from the output files of the SAS2H/ORIGIN-S sequence of the SCALE Version 4.3 modular code system, as documented in References 2.1.1 and 2.1.2, and are included in Attachment II

  14. Hydrogen production from coal using a nuclear heat source

    International Nuclear Information System (INIS)

    Quade, R.N.

    1977-01-01

    A strong candidate for hydrogen production in the intermediate time frame of 1990 to 1995 is a coal-based process using a high-temperature gas-cooled reactor (HTGR) as a heat source. Expected process efficiencies in the range of 60 to 70% are considerably higher than all other hydrogen production processes except steam reforming of a natural gas - a feedstock which may not be available in large quantities in this time frame. The process involves the preparation of a coal liquid, hydrogasification of that liquid, and steam reforming of the resulting gaseous or light liquid product. Bench-scale experimental work on the hydrogasification of coal liquids is being carried out. A study showing process efficiency and cost of hydrogen vs nuclear reactor core outlet temperature has been completed and shows diminishing returns at process temperatures above about 1500 0 F. (author)

  15. Hydrogen production from coal using a nuclear heat source

    Science.gov (United States)

    Quade, R. N.

    1976-01-01

    A strong candidate for hydrogen production in the intermediate time frame of 1985 to 1995 is a coal-based process using a high-temperature gas-cooled reactor (HTGR) as a heat source. Expected process efficiencies in the range of 60 to 70% are considerably higher than all other hydrogen production processes except steam reforming of a natural gas. The process involves the preparation of a coal liquid, hydrogasification of that liquid, and steam reforming of the resulting gaseous or light liquid product. A study showing process efficiency and cost of hydrogen vs nuclear reactor core outlet temperature has been completed, and shows diminishing returns at process temperatures above about 1500 F. A possible scenario combining the relatively abundant and low-cost Western coal deposits with the Gulf Coast hydrogen users is presented which provides high-energy density transportation utilizing coal liquids and uranium.

  16. Environmental assessment for radioisotope heat source fuel processing and fabrication

    International Nuclear Information System (INIS)

    1991-07-01

    DOE has prepared an Environmental Assessment (EA) for radioisotope heat source fuel processing and fabrication involving existing facilities at the Savannah River Site (SRS) near Aiken, South Carolina and the Los Alamos National Laboratory (LANL) near Los Alamos, New Mexico. The proposed action is needed to provide Radioisotope Thermoelectric Generators (RTG) to support the National Aeronautics and Space Administration's (NASA) CRAF and Cassini Missions. Based on the analysis in the EA, DOE has determined that the proposed action does not constitute a major Federal action significantly affecting the quality of the human environment within the meaning of the National Environmental Policy Act (NEPA) of 1969. Therefore, an Environmental Impact Statement is not required. 30 refs., 5 figs

  17. Laser heated solenoid as a neutron source facility

    International Nuclear Information System (INIS)

    Steinhauer, L.C.; Rose, P.H.

    1975-01-01

    Conceptual designs are presented for a radiation test facility based on a laser heated plasma confined in a straight solenoid. The thin plasma column, a few meters in length and less than a centimeter in diameter, serves as a line source of neutrons. Test samples are located within or just behind the plasma tube, at a radius of 1-2 cm from the axis. The plasma is heated by an axially-directed powerful long-wavelength laser beam. The plasma is confined radially in the intense magnetic field supplied by a pulsed solenoid surrounding the plasma tube. The facility is pulsed many times a second to achieve a high time-averaged neutron flux on the test samples. Based on component performance achievable in the near term (e.g., magnetic field, laser pulse energy) and assuming classical physical processes, it appears that average fluxes of 10 13 to 10 14 neutrons/cm 2 -sec can be achieved in such a device. The most severe technical problems in such a facility appear to be rapid pulsing design and lifetime of some electrical and laser components

  18. Advanced neutron source design: burnout heat flux correlation development

    International Nuclear Information System (INIS)

    Gambill, W.R.; Mochizuki, T.

    1988-01-01

    In the advanced neutron source reactor (ANSR) fuel element region, heat fluxes will be elevated. Early designs corresponded to average and estimated hot-spot fluxes of 11 to 12 and 21 to 22 MW/m 2 , respectively. Design changes under consideration may lower these values to ∼ 9 and 17 MW/m 1 . In either event, the development of a satisfactory burnout heat flux correlation is an important element among the many thermal-hydraulic design issues, since the critical power ratio will depend in part on its validity. Relatively little work in the area of subcooled-flow burnout has been published over the past 12 yr. The authors have compared seven burnout correlations and modifications therefore with several sets of experimental data, of which the most relevant to the ANS core are those referenced. The best overall agreement between the correlations tested and these data is currently provided by a modification of Thorgerson et al. correlation. The variable ranges of the experimental data are outlined and the results of the correlation comparisons are summarized

  19. Nonlinear radiative heat flux and heat source/sink on entropy generation minimization rate

    Science.gov (United States)

    Hayat, T.; Khan, M. Waleed Ahmed; Khan, M. Ijaz; Alsaedi, A.

    2018-06-01

    Entropy generation minimization in nonlinear radiative mixed convective flow towards a variable thicked surface is addressed. Entropy generation for momentum and temperature is carried out. The source for this flow analysis is stretching velocity of sheet. Transformations are used to reduce system of partial differential equations into ordinary ones. Total entropy generation rate is determined. Series solutions for the zeroth and mth order deformation systems are computed. Domain of convergence for obtained solutions is identified. Velocity, temperature and concentration fields are plotted and interpreted. Entropy equation is studied through nonlinear mixed convection and radiative heat flux. Velocity and temperature gradients are discussed through graphs. Meaningful results are concluded in the final remarks.

  20. The effect of location of a convective heat source on displacement ventilation: CFD study

    Energy Technology Data Exchange (ETDEWEB)

    Park, H.J.; Holland, D. [Dunham Associates, Inc., Minneapolis, MN (United States). Advanced Technologies Group

    2001-08-01

    Two-dimensional computational simulations are performed to examine the effect of vertical location of a convective heat source on thermal displacement ventilation systems. In this study, a heat source is modeled with seven different heights from the floor (0.5, 0.75, 1.0, 1.25, 1.5, 1.75, 2.0 m) in a displacement ventilation environment. The flow and temperature fields in thermal displacement ventilation systems vary depending on the location of the heat source. As the heat source rises, the convective heat gain from the heat source to an occupied zone becomes less significant. This effect changes the temperature field and results in the reduction of the cooling load in the occupied zone. The stratification level is also affected by the heat source location at a given flow rate. (author)

  1. Optimal design of district heating and cooling pipe network of seawater-source heat pump

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiang-li; Duanmu, Lin; Shu, Hai-wen [School of Civil and Hydraulic Engineering, Dalian University of Technology, Dalian, Liaoning Province 116024 (China)

    2010-01-15

    The district heating and cooling (DHC) system of a seawater-source heat pump is large system engineering. The investments and the operational cost of DHC pipe network are higher than a tradition system. Traditional design methods only satisfy the needs of the technology but dissatisfy the needs of the economy, which not only waste a mass of money but also bring problems to the operation, the maintenance and the management. So we build a least-annualized-cost global optimal mathematic model that comprises all constrict conditions. Furthermore, this model considers the variety of heating load and cooling load, the operational adjustment in different periods of the year. Genetic algorithm (GA) is used to obtain the optimal combinations of discrete diameters. Some operators of GA are selected to reduce the calculation time and obtain good calculation accuracy. This optimal method is used to the design of the DHC network of Xinghai Bay commercial district which is a real engineering. The design optimization can avoid the matter of the hydraulic unbalance of the system, enhance the running efficiency and greatly reduce the annualized-cost comparing with the traditional design method. (author)

  2. The application of ground source heat pumps to a subdivision-wide district heating system

    International Nuclear Information System (INIS)

    Ciavaglia, L.

    2005-01-01

    Design guidelines for economic ground source heat pumps (GSHP) in district energy systems were presented. The broad economics of using central GSHP in a community district energy system were examined. Design parameters needed to utilize GSHP in district energy system were outlined. The sensitivity of energy prices and the costs of major capital were reviewed. District heating load duration curves were outlined. It was suggested that varying GSHP capacity from 0 to 100 per cent of load was advisable. In addition, capacity should be balanced with gas boiler technology. The amortizing of capital within energy costs was recommended. It was suggested that the best scenario was a minimum of 50 per cent ground energy. Details of pipings and heat exchanger costs were presented, along with costs for gas boilers and gas costs for the district energy system. Charts of current costing and reduction of piping capital were included. It was concluded that GSHP can be a viable component of a district energy system, as a GSHP based district energy system can provide more stable energy prices than conventional fossil fuel systems. It was suggested that sizing of GSHP at, or near, 40 per cent of peak demand provided optimal conditions with respect to energy cost and use of earth energy. tabs., figs

  3. Measured Performance of a Low Temperature Air Source Heat Pump

    Energy Technology Data Exchange (ETDEWEB)

    R.K. Johnson

    2013-09-01

    A 4-ton Low Temperature Heat Pump (LTHP) manufactured by Hallowell International was installed in a residence near New Haven, Connecticut and monitored over two winters of operation. After attending to some significant service issues, the heat pump operated as designed. This report should be considered a review of the dual compressor “boosted heat pump” technology. The Low Temperature Heat Pump system operates with four increasing levels of capacity (heat output) as the outdoor temperature drops.

  4. Ground source heat pumps (GSHP) for heating and cooling in Greece

    Science.gov (United States)

    Dimera, Nikoletta

    This report presents the results of a theoretical study about the feasibility of closed loop Ground Source Heat Pumps (GSHP) for heating and cooling in Greece in terms of their impact on the capital and running costs of the building services systems of the buildings. The main aim of carrying out this study was to investigate if the heating and cooling potential of the ground could be utilized cost efficiently to serve the buildings energy demand in the Greek region. At first, an existing implementation of a closed loop GSHP system in Greece is presented and its efficiency is discussed. The aim of doing so was to understand the way of sizing such systems and the efficiency of this technology in Greek climatic and ground conditions. In a separate part of this report, the impact of different user behaviour and of various ways of sizing a GSHP system is investigated in terms of the cost impact of the examined different options as well as of their effect on the internal health and comfort conditions. After the building simulation under different scenarios, it was concluded that the user behavior - the operation of windows mostly - can result in great savings on the annual energy bills. The conclusions of this first part of the report about the user behaviour and the way of sizing GSHP systems were utilized in the next part of it, where a GSHP system is proposed for a building currently under construction in central Greece. A simple 30-year cost analysis was used in order to estimate the performance of the proposed GSHP system in economic terms and to compare it with the conventional HVAC system commonly used in Greece. According to the results of the analysis, the capital cost of installing a GSHP system for heating and cooling in buildings in Greece appears higher than the cost of conventional HVAC systems. More specifically, the capital cost of an installation for heating including gas boilers and a cooling system based on air conditioning split units is about the

  5. Nuclear safety inspection in treatment process for SG heat exchange tubes deficiency of unit 1, TNPS

    International Nuclear Information System (INIS)

    Zhang Chunming; Song Chenxiu; Zhao Pengyu; Hou Wei

    2006-01-01

    This paper describes treatment process for SG heat exchange tubes deficiency of Unit 1, TNPS, nuclear safety inspection of Northern Regional Office during treatment process for deficiency and further inspection after deficiency had been treated. (authors)

  6. About the possible options for models of convective heat transfer in closed volumes with local heating source

    Directory of Open Access Journals (Sweden)

    Maksimov Vyacheslav I.

    2015-01-01

    Full Text Available Results of mathematical modeling of convective heat transfer in air area surrounded on all sides enclosing structures, in the presence of heat source at the lower boundary of the media are presented. Solved the system of differential equations of unsteady Navier-Stokes equations with the appropriate initial and boundary conditions. The process of convective heat transfer is calculated using the models of turbulence Prandtl and Prandtl-Reichard. Takes into account the processes of heat exchange region considered with the environment. Is carried out the analysis of the dimensionless heat transfer coefficient at interfaces “air – enclosures”. The distributions average along the gas temperature range are obtained.

  7. Radiation Protection and Safety of Radiation Sources: International Basic Safety Standards. General Safety Requirements. Pt. 3 (Chinese Edition)

    International Nuclear Information System (INIS)

    2014-01-01

    This publication is the new edition of the International Basic Safety Standards. The edition is co-sponsored by seven other international organizations — European Commission (EC/Euratom), FAO, ILO, OECD/NEA, PAHO, UNEP and WHO. It replaces the interim edition that was published in November 2011 and the previous edition of the International Basic Safety Standards which was published in 1996. It has been extensively revised and updated to take account of the latest finding of the United Nations Scientific Committee on the Effects of Atomic Radiation, and the latest recommendations of the International Commission on Radiological Protection. The publication details the requirements for the protection of people and the environment from harmful effects of ionizing radiation and for the safety of radiation sources. All circumstances of radiation exposure are considered

  8. Radiation protection and safety of radiation sources: International basic safety standards. General safety requirements. Pt. 3 (French Edition)

    International Nuclear Information System (INIS)

    2016-01-01

    This publication is the new edition of the International Basic Safety Standards. The edition is co-sponsored by seven other international organizations — European Commission (EC/Euratom), FAO, ILO, OECD/NEA, PAHO, UNEP and WHO. It replaces the interim edition that was published in November 2011 and the previous edition of the International Basic Safety Standards which was published in 1996. It has been extensively revised and updated to take account of the latest finding of the United Nations Scientific Committee on the Effects of Atomic Radiation, and the latest recommendations of the International Commission on Radiological Protection. The publication details the requirements for the protection of people and the environment from harmful effects of ionizing radiation and for the safety of radiation sources. All circumstances of radiation exposure are considered

  9. Radiation Protection and Safety of Radiation Sources: International Basic Safety Standards. General Safety Requirements. Pt. 3 (Arabic Edition)

    International Nuclear Information System (INIS)

    2015-01-01

    This publication is the new edition of the International Basic Safety Standards. The edition is co-sponsored by seven other international organizations — European Commission (EC/Euratom), FAO, ILO, OECD/NEA, PAHO, UNEP and WHO. It replaces the interim edition that was published in November 2011 and the previous edition of the International Basic Safety Standards which was published in 1996. It has been extensively revised and updated to take account of the latest finding of the United Nations Scientific Committee on the Effects of Atomic Radiation, and the latest recommendations of the International Commission on Radiological Protection. The publication details the requirements for the protection of people and the environment from harmful effects of ionizing radiation and for the safety of radiation sources. All circumstances of radiation exposure are considered

  10. Phase 2 safety analysis report: National Synchrotron Light Source

    International Nuclear Information System (INIS)

    Stefan, P.

    1989-06-01

    The Phase II program was established in order to provide additional space for experiments, and also staging and equipment storage areas. It also provides additional office space and new types of advanced instrumentation for users. This document will deal with the new safety issues resulting from this extensive expansion program, and should be used as a supplement to BNL Report No. 51584 ''National Synchrotron Light Source Safety Analysis Report,'' July 1982 (hereafter referred to as the Phase I SAR). The initial NSLS facility is described in the Phase I SAR. It comprises two electron storage rings, an injection system common to both, experimental beam lines and equipment, and office and support areas, all of which are housed in a 74,000 sq. ft. building. The X-ray Ring provides for 28 primary beam ports and the VUV Ring, 16. Each port is capable of division into 2 or 3 separate beam lines. All ports receive their synchrotron light from conventional bending magnet sources, the magnets being part of the storage ring lattice. 4 refs

  11. Nuclear and geothermal energy as a direct heat source

    International Nuclear Information System (INIS)

    Field, A.A.

    1976-01-01

    After some remarks on economic aspects, the swimming pool reactor simplified for the purpose of heat generation is described, the core of which supplies heat of 100-120 0 C for district heating. In this context, ways of storing waste heat are discussed. The alternative is pointed out that energy may be transferred by means of hydrogen. In conclusion, it is demonstrated on a French plant how geothermal water can be used directly via heat exchangers for district heating. (UA/LN) [de

  12. Application of sorption heat pumps for increasing of new power sources efficiency

    Science.gov (United States)

    Vasiliev, L.; Filatova, O.; Tsitovich, A.

    2010-07-01

    In the 21st century the way to increase the efficiency of new sources of energy is directly related with extended exploration of renewable energy. This modern tendency ensures the fuel economy needs to be realized with nature protection. The increasing of new power sources efficiency (cogeneration, trigeneration systems, fuel cells, photovoltaic systems) can be performed by application of solid sorption heat pumps, regrigerators, heat and cold accumulators, heat transformers, natural gas and hydrogen storage systems and efficient heat exchangers.

  13. Prediction of Heat Transfer Performance on Horizontal U-Shaped Heat Exchanger in Passive Safety System Using MARS

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Seong-Su; Hong, Soon-Joon [FNC Tech, Yongin (Korea, Republic of); Cho, Hyoung-Kyu; Park, Goon-Cherl [Seoul National University, Seoul (Korea, Republic of)

    2015-10-15

    The design and the safety analysis of the passive safety systems are performed mainly using the best-estimate thermal-hydraulic analysis codes such as RELAP5 and MARS. This study developed the heat transfer model package for the horizontal U-shaped HX submerged in a pool by improving the horizontal in-tube condensation model and developing the outside-tube natural convective nucleate boiling model. This paper presents the HX model package and the validation results against the passive safety system-related experimental data of PASCAL and ATLAS-PAFS. This study developed the heat transfer model package of the horizontal U-shaped HX submerged in a pool in order to obtain a reliable prediction of the HX heat removal performance of the passive safety system, especially PAFS, using MARS. From the validation results, the proposed model package provided the improved prediction of HX performance (condensation, natural convective nucleate boiling, and heat removal rate of the HX) compared to the default model in MARS.

  14. Ground Source Heat Pumps vs. Conventional HVAC: A Comparison of Economic and Environmental Costs

    Science.gov (United States)

    2009-03-26

    of systems are surface water heat pumps (SWHPs), ground water heat pumps (GWHPs), and ground coupled heat pumps ( GCHPs ) (Kavanaugh & Rafferty, 1997...Kavanaugh & Rafferty, 1997). Ground Coupled Heat Pumps (Closed-Loop Ground Source Heat Pumps) GCHPs , otherwise known as closed-loop GSHPs, are the...Significant confusion has arisen through the use of GCHP and closed-loop GSHP terminology. Closed-loop GSHP is the preferred nomenclature for this

  15. local alternative sources for cogeneration combined heat and power system

    Science.gov (United States)

    Agll, Abdulhakim Amer

    Global demand for energy continues to grow while countries around the globe race to reduce their reliance on fossil fuels and greenhouse gas emissions by implementing policy measures and advancing technology. Sustainability has become an important issue in transportation and infrastructure development projects. While several agencies are trying to incorporate a range of sustainability measures in their goals and missions, only a few planning agencies have been able to implement these policies and they are far from perfect. The low rate of success in implementing sustainable policies is primarily due to incomplete understanding of the system and the interaction between various elements of the system. The conventional planning efforts focuses mainly on performance measures pertaining to the system and its impact on the environment but seldom on the social and economic impacts. The objective of this study is to use clean and alternative energy can be produced from many sources, and even use existing materials for energy generation. One such pathway is using wastewater, animal and organic waste, or landfills to create biogas for energy production. There are three tasks for this study. In topic one evaluated the energy saving that produced from combined hydrogen, heat, and power and mitigate greenhouse gas emissions by using local sustainable energy at the Missouri S&T campus to reduce energy consumption and fossil fuel usage. Second topic aimed to estimate energy recovery and power generation from alternative energy source by using Rankin steam cycle from municipal solid waste at Benghazi-Libya. And the last task is in progress. The results for topics one and two have been presented.

  16. ITER safety task NID-5a: ITER tritium environmental source terms - safety analysis basis

    International Nuclear Information System (INIS)

    Natalizio, A.; Kalyanam, K.M.

    1994-09-01

    The Canadian Fusion Fuels Technology Project's (CFFTP) is part of the contribution to ITER task NID-5a, Initial Tritium Source Term. This safety analysis basis constitutes the first part of the work for establishing tritium source terms and is intended to solicit comments and obtain agreement. The analysis objective is to provide an early estimate of tritium environmental source terms for the events to be analyzed. Events that would result in the loss of tritium are: a Loss of Coolant Accident (LOCA), a vacuum vessel boundary breach. a torus exhaust line failure, a fuelling machine process boundary failure, a fuel processing system process boundary failure, a water detritiation system process boundary failure and an isotope separation system process boundary failure. 9 figs

  17. Environmental assessment for the relocation and storage of isotopic heat sources, Hanford Site, Richland, Washington

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-06-01

    As part of a bilateral agreement between the Federal Minister for Research and Technology of the Federal Republic of Germany (FRG) and the DOE, Pacific Northwest National Laboratory (PNNL) developed processes for the treatment and immobilization of high-level radioactive waste. One element of this bilateral agreement was the production of sealed isotopic heat sources. During the mid-1980s, 30 sealed isotopic heat sources were manufactured. The sources contain a total of approximately 8.3 million curies consisting predominantly of cesium-137 and strontium-90 with trace amounts of transuranic contamination. Currently, the sources are stored in A-Cell of the 324 Building. Intense radiation fields from the sources are causing the cell windows and equipment to deteriorate. Originally, it was not intended to store the isotopic heat sources for this length of time in A-cell. The 34 isotopic heat sources are classified as remote handled transuranic wastes. Thirty-one of the isotopic heat sources are sealed, and seals on the three remaining isotopic heat sources have not been verified. However, a decision has been made to place the remaining three isotopic heat sources in the CASTOR cask(s). The Washington State Department of Health (WDOH) has concurred that isotopic heat sources with verified seals or those placed into CASTOR cask(s) can be considered sealed (no potential to emit radioactive air emissions) and are exempt from WAC Chapter 246-247, Radiation Protection-Air Emissions.

  18. Environmental assessment for the relocation and storage of isotopic heat sources, Hanford Site, Richland, Washington

    International Nuclear Information System (INIS)

    1997-06-01

    As part of a bilateral agreement between the Federal Minister for Research and Technology of the Federal Republic of Germany (FRG) and the DOE, Pacific Northwest National Laboratory (PNNL) developed processes for the treatment and immobilization of high-level radioactive waste. One element of this bilateral agreement was the production of sealed isotopic heat sources. During the mid-1980s, 30 sealed isotopic heat sources were manufactured. The sources contain a total of approximately 8.3 million curies consisting predominantly of cesium-137 and strontium-90 with trace amounts of transuranic contamination. Currently, the sources are stored in A-Cell of the 324 Building. Intense radiation fields from the sources are causing the cell windows and equipment to deteriorate. Originally, it was not intended to store the isotopic heat sources for this length of time in A-cell. The 34 isotopic heat sources are classified as remote handled transuranic wastes. Thirty-one of the isotopic heat sources are sealed, and seals on the three remaining isotopic heat sources have not been verified. However, a decision has been made to place the remaining three isotopic heat sources in the CASTOR cask(s). The Washington State Department of Health (WDOH) has concurred that isotopic heat sources with verified seals or those placed into CASTOR cask(s) can be considered sealed (no potential to emit radioactive air emissions) and are exempt from WAC Chapter 246-247, Radiation Protection-Air Emissions

  19. Experimental Study of the Performance of Air Source Heat Pump Systems Assisted by Low-Temperature Solar-Heated Water

    Directory of Open Access Journals (Sweden)

    Jinshun Wu

    2013-01-01

    Full Text Available Due to the low temperatures, the heating efficiency of air source heat pump systems during the winter is very low. To address this problem, a low-temperature solar hot water system was added to a basic air source heat pump system. Several parameters were tested and analyzed. The heat collection efficiency of the solar collector was analyzed under low-temperature conditions. The factors that affect the performance of the heat pumps, such as the fluid temperature, pressure, and energy savings, were analyzed for cases where the solar energy auxiliary heat pump and the air source heat pump are used independently. The optimal heating temperature and the changes in the fluid temperature were determined. The influence of the compression ratio and the coefficient of performance (COP were investigated theoretically. The results revealed the parameters that are important to the performance of the system. Several measures for improving the COP of the heat pump units are provided for other applications and future research.

  20. Heated probe diagnostic inside of the gas aggregation nanocluster source

    Science.gov (United States)

    Kolpakova, Anna; Shelemin, Artem; Kousal, Jaroslav; Kudrna, Pavel; Tichy, Milan; Biederman, Hynek; Surface; Plasma Science Team

    2016-09-01

    Gas aggregation cluster sources (GAS) usually operate outside common working conditions of most magnetrons and the size of nanoparticles created in GAS is below that commonly studied in dusty plasmas. Therefore, experimental data obtained inside the GAS are important for better understanding of process of nanoparticles formation. In order to study the conditions inside the gas aggregation chamber, special ``diagnostic GAS'' has been constructed. It allows simultaneous monitoring (or spatial profiling) by means of optical emission spectroscopy, mass spectrometry and probe diagnostic. Data obtained from Langmuir and heated probes map the plasma parameters in two dimensions - radial and axial. Titanium has been studied as an example of metal for which the reactive gas in the chamber starts nanoparticles production. Three basic situations were investigated: sputtering from clean titanium target in argon, sputtering from partially pre-oxidized target and sputtering with oxygen introduced into the discharge. It was found that during formation of nanoparticles the plasma parameters differ strongly from the situation without nanoparticles. These experimental data will support the efforts of more realistic modeling of the process. Czech Science Foundation 15-00863S.

  1. Exergoeconomic analysis of a solar assisted ground-source heat pump greenhouse heating system

    International Nuclear Information System (INIS)

    Ozgener, Onder; Hepbasli, Arif

    2005-01-01

    EXCEM analysis may prove useful to investigators in engineering and other disciplines due to the methodology are being based on the quantities exergy, cost, energy and mass. The main objective of the present study is to investigate between capital costs and thermodynamic losses for devices in solar assisted ground-source heat pump greenhouse heating system (SAGSHPGHS) with a 50 m vertical 32 mm nominal diameter U-bend ground heat exchanger. This system was designed and installed at the Solar Energy Institute, Ege University, Izmir, Turkey. Thermodynamic loss rate-to-capital cost ratios are used to show that, for components and the overall system, a systematic correlation appears to exist between capital cost and exergy loss (total or internal), but not between capital cost and energy loss or external exergy loss. This correlation may imply that devices in successful air conditioning are configured so as to achieve an overall optimal design, by appropriately balancing the thermodynamic (exergy-based) and economic characteristics of the overall system and its devices. The results may, (i) provide useful insights into the relations between thermodynamics and economics, both in general and for SAGSHPGHS (ii) help demonstrate the merits of second-law analysis. It is observed from the results that the maximum exergy destructions in the system particularly occur due to the electrical, mechanical and isentropic efficiencies and emphasize the need for paying close attention to the selection of this type of equipment, since components of inferior performance can considerably reduce the overall performance of the system. In conjunction with this, the total exergy losses values are obtained to be from 0.010 kW to 0.480 kW for the system. As expected, the largest energy and exergy losses occur in the greenhouse and compressor. The ratio of thermodynamic loss rate to capital cost values are obtained for a range from 0.035 to 1.125

  2. Energy and exergy analysis of a double effect absorption refrigeration system based on different heat sources

    International Nuclear Information System (INIS)

    Kaynakli, Omer; Saka, Kenan; Kaynakli, Faruk

    2015-01-01

    Highlights: • Energy and exergy analysis was performed on double effect series flow absorption refrigeration system. • The refrigeration system runs on various heat sources such as hot water, hot air and steam. • A comparative analysis was carried out on these heat sources in terms of exergy destruction and mass flow rate of heat source. • The effect of heat sources on the exergy destruction of high pressure generator was investigated. - Abstract: Absorption refrigeration systems are environmental friendly since they can utilize industrial waste heat and/or solar energy. In terms of heat source of the systems, researchers prefer one type heat source usually such as hot water or steam. Some studies can be free from environment. In this study, energy and exergy analysis is performed on a double effect series flow absorption refrigeration system with water/lithium bromide as working fluid pair. The refrigeration system runs on various heat sources such as hot water, hot air and steam via High Pressure Generator (HPG) because of hot water/steam and hot air are the most common available heat source for absorption applications but the first law of thermodynamics may not be sufficient analyze the absorption refrigeration system and to show the difference of utilize for different type heat source. On the other hand operation temperatures of the overall system and its components have a major effect on their performance and functionality. In this regard, a parametric study conducted here to investigate this effect on heat capacity and exergy destruction of the HPG, coefficient of performance (COP) of the system, and mass flow rate of heat sources. Also, a comparative analysis is carried out on several heat sources (e.g. hot water, hot air and steam) in terms of exergy destruction and mass flow rate of heat source. From the analyses it is observed that exergy destruction of the HPG increases at higher temperature of the heat sources, condenser and absorber, and lower

  3. A study of Ground Source Heat Pump based on a heat infiltrates coupling model established with FEFLOW

    Science.gov (United States)

    Chen, H.; Hu, C.; Chen, G.; Zhang, Q.

    2017-12-01

    Geothermal heat is a viable source of energy and its environmental impact in terms of CO2 emissions is significantly lower than conventional fossil fuels. it is vital that engineers acquire a proper understanding about the Ground Source Heat Pump (GSHP). In this study, the model of the borehole exchanger under conduction manners and heat infiltrates coupling manners was established with FEFLOW. The energy efficiency, heat transfer endurance and heat transfer in the unit depth were introduced to quantify the energy efficient and the endurance period. The performance of a the Borehole Exchanger (BHE) in soil with and without groundwater seepage was analyzed of heat transfer process between the soil and the working fluid. Basing on the model, the varied regularity of energy efficiency performance an heat transfer endurance with the conditions including the different configuration of the BHE, the soil properties, thermal load characteristic were discussed. Focus on the heat transfer process in multi-layer soil which one layer exist groundwater flow. And an investigation about thermal dispersivity was also analyzed its influence on heat transfer performance. The final result proves that the model of heat infiltrates coupling model established in this context is reasonable, which can be applied to engineering design.

  4. Temperature distribution of a simplified rotor due to a uniform heat source

    Science.gov (United States)

    Welzenbach, Sarah; Fischer, Tim; Meier, Felix; Werner, Ewald; kyzy, Sonun Ulan; Munz, Oliver

    2018-03-01

    In gas turbines, high combustion efficiency as well as operational safety are required. Thus, labyrinth seal systems with honeycomb liners are commonly used. In the case of rubbing events in the seal system, the components can be damaged due to cyclic thermal and mechanical loads. Temperature differences occurring at labyrinth seal fins during rubbing events can be determined by considering a single heat source acting periodically on the surface of a rotating cylinder. Existing literature analysing the temperature distribution on rotating cylindrical bodies due to a stationary heat source is reviewed. The temperature distribution on the circumference of a simplified labyrinth seal fin is calculated using an available and easy to implement analytical approach. A finite element model of the simplified labyrinth seal fin is created and the numerical results are compared to the analytical results. The temperature distributions calculated by the analytical and the numerical approaches coincide for low sliding velocities, while there are discrepancies of the calculated maximum temperatures for higher sliding velocities. The use of the analytical approach allows the conservative estimation of the maximum temperatures arising in labyrinth seal fins during rubbing events. At the same time, high calculation costs can be avoided.

  5. Linking potential heat source and sink to urban heat island: Heterogeneous effects of landscape pattern on land surface temperature.

    Science.gov (United States)

    Li, Weifeng; Cao, Qiwen; Lang, Kun; Wu, Jiansheng

    2017-05-15

    Rapid urbanization has significantly contributed to the development of urban heat island (UHI). Regulating landscape composition and configuration would help mitigate the UHI in megacities. Taking Shenzhen, China, as a case study area, we defined heat source and heat sink and identified strong and weak sources as well as strong and weak sinks according to the natural and socioeconomic factors influencing land surface temperature (LST). Thus, the potential thermal contributions of heat source and heat sink patches were differentiated. Then, the heterogeneous effects of landscape pattern on LST were examined by using semiparametric geographically weighted regression (SGWR) models. The results showed that landscape composition has more significant effects on thermal environment than configuration. For a strong source, the percentage of patches has a positive impact on LST. Additionally, when mosaicked with some heat sink, even a small improvement in the degree of dispersion of a strong source helps to alleviate UHI. For a weak source, the percentage and density of patches have positive impacts on LST. For a strong sink, the percentage, density, and degree of aggregation of patches have negative impacts on LST. The effects of edge density and patch shape complexity vary spatially with the fragmentation of a strong sink. Similarly, the impacts of a weak sink are mainly exerted via the characteristics of percent, density, and shape complexity of patches. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. 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.

  7. A concept of passive safety pressurized water reactor system with inherent matching nature of core heat generation and heat removal

    International Nuclear Information System (INIS)

    Murao, Yoshio; Araya, Fumimasa; Iwamura, Takamichi; Okumura, Keisuke

    1995-01-01

    The reduction of manpower in operation and maintenance by simplification of the system are essential to improve the safety and the economy of future light water reactors. At the Japan Atomic Energy Research Institute (JAERI), a concept of a simplified passive safety reactor system JPSR was developed for this purpose and in the concept minimization of developing work and conservation of scale-up capability in design were considered. The inherent matching nature of core heat generation and heat removal rate is introduced by the core with high reactivity coefficient for moderator density and low reactivity coefficient for fuel temperature (Doppler effect) and once-through steam generators (SGs). This nature makes the nuclear steam supply system physically-slave for the steam and energy conversion system by controlling feed water mass flow rate. The nature can be obtained by eliminating chemical shim and adopting in-vessel control rod drive mechanism (CRDM) units and a low power density core. In order to simplify the system, a large pressurizer, canned pumps, passive residual heat removal systems with air coolers as a final heat sink and passive coolant injection system are adopted and the functions of volume and boron concentration control and seal water supply are eliminated from the chemical and volume control system (CVCS). The emergency diesel generators and auxiliary component cooling system of 'safety class' for transferring heat to sea water as a final heat sink in emergency are also eliminated. All of systems are built in the containment except for the air coolers of the passive residual heat removal system. The analysis of the system revealed that the primary coolant expansion in 100% load reduction in 60 s can be mitigated in the pressurizer without actuating the pressure relief valves and the pressure in 50% load change in 30 s does not exceed the maximum allowable pressure in accidental conditions in regardless of pressure regulation. (author)

  8. Variable Conductance Heat Pipe Cooling of Stirling Convertor and General Purpose Heat Source

    Science.gov (United States)

    Tarau, Calin; Schwendeman, Carl; Anderson, William G.; Cornell, Peggy A.; Schifer, Nicholas A.

    2013-01-01

    In a Stirling Radioisotope Power System (RPS), heat must be continuously removed from the General Purpose Heat Source (GPHS) modules to maintain the modules and surrounding insulation at acceptable temperatures. The Stirling convertor normally provides this cooling. If the Stirling convertor stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS at the cost of an early termination of the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) can be used to passively allow multiple stops and restarts of the Stirling convertor. In a previous NASA SBIR Program, Advanced Cooling Technologies, Inc. (ACT) developed a series of sodium VCHPs as backup cooling systems for Stirling RPS. The operation of these VCHPs was demonstrated using Stirling heater head simulators and GPHS simulators. In the most recent effort, a sodium VCHP with a stainless steel envelope was designed, fabricated and tested at NASA Glenn Research Center (GRC) with a Stirling convertor for two concepts; one for the Advanced Stirling Radioisotope Generator (ASRG) back up cooling system and one for the Long-lived Venus Lander thermal management system. The VCHP is designed to activate and remove heat from the stopped convertor at a 19 degC temperature increase from the nominal vapor temperature. The 19 degC temperature increase from nominal is low enough to avoid risking standard ASRG operation and spoiling of the Multi-Layer Insulation (MLI). In addition, the same backup cooling system can be applied to the Stirling convertor used for the refrigeration system of the Long-lived Venus Lander. The VCHP will allow the refrigeration system to: 1) rest during transit at a lower temperature than nominal; 2) pre-cool the modules to an even lower temperature before the entry in Venus atmosphere; 3) work at nominal temperature on Venus surface; 4) briefly stop multiple times on the Venus surface to allow scientific measurements. This paper presents the experimental

  9. An analysis of solar assisted ground source heat pumps in cold climates

    International Nuclear Information System (INIS)

    Emmi, Giuseppe; Zarrella, Angelo; De Carli, Michele; Galgaro, Antonio

    2015-01-01

    Highlights: • The work focuses on solar assisted ground source heat pump in cold climates. • Multi-year simulations of SAGSHP, are carried out in six cold locations. • GSHP and SAGSHP are compared. • The effect of total borehole length on the heat pump energy efficiency is studied. • A dedicated control strategy is used to manage both solar and ground loops. - Abstract: Exploiting renewable energy sources for air-conditioning has been extensively investigated over recent years, and many countries have been working to promote the use of renewable energy to decrease energy consumption and CO_2 emissions. Electrical heat pumps currently represent the most promising technology to reduce fossil fuel usage. While ground source heat pumps, which use free heat sources, have been taking significant steps forward and despite the fact that their energy performance is better than that of air source heat pumps, their development has been limited by their high initial investment cost. An alternative solution is one that uses solar thermal collectors coupled with a ground source heat pump in a so-called solar assisted ground source heat pump. A ground source heat pump system, used to heat environments located in a cold climate, was investigated in this study. The solar assisted ground source heat pump extracted heat from the ground by means of borehole heat exchangers and it injected excess solar thermal energy into the ground. Building load profiles are usually heating dominated in cold climates, but when common ground source heat pump systems are used only for heating, their performance decreases due to an unbalanced ground load. Solar thermal collectors can help to ensure that systems installed in cold zones perform more efficiently. Computer simulations using a Transient System Simulation (TRNSYS) tool were carried out in six cold locations in order to investigate solar assisted ground source heat pumps. The effect of the borehole length on the energy efficiency of

  10. Spallation Neutron Source Accelerator Facility Target Safety and Non-safety Control Systems

    International Nuclear Information System (INIS)

    Battle, Ronald E.; DeVan, B.; Munro, John K. Jr.

    2006-01-01

    The Spallation Neutron Source (SNS) is a proton accelerator facility that generates neutrons for scientific researchers by spallation of neutrons from a mercury target. The SNS became operational on April 28, 2006, with first beam on target at approximately 200 W. The SNS accelerator, target, and conventional facilities controls are integrated by standardized hardware and software throughout the facility and were designed and fabricated to SNS conventions to ensure compatibility of systems with Experimental Physics Integrated Control System (EPICS). ControlLogix Programmable Logic Controllers (PLCs) interface to instruments and actuators, and EPICS performs the high-level integration of the PLCs such that all operator control can be accomplished from the Central Control room using EPICS graphical screens that pass process variables to and from the PLCs. Three active safety systems were designed to industry standards ISA S84.01 and IEEE 603 to meet the desired reliability for these safety systems. The safety systems protect facility workers and the environment from mercury vapor, mercury radiation, and proton beam radiation. The facility operators operated many of the systems prior to beam on target and developed the operating procedures. The safety and non-safety control systems were tested extensively prior to beam on target. This testing was crucial to identify wiring and software errors and failed components, the result of which was few problems during operation with beam on target. The SNS has continued beam on target since April to increase beam power, check out the scientific instruments, and continue testing the operation of facility subsystems

  11. Solar heating - a major source of renewable energy

    International Nuclear Information System (INIS)

    Bosselaar, L.

    2001-01-01

    Actions that can be taken to increase the uptake of technology for solar water heaters and solar buildings are discussed. An overview of existing technology covers solar water heating, solar buildings, space heating, solar cooling, solar drying, solar desalination. Solar water heating, solar buildings and solar crop drying are discussed individually under the sub-headings of (a) the technology; (b) the market; (c) potential; (d) economics and (e) market acceleration strategies. Other subjects discussed are market acceleration, main opportunities, R and D needs and conclusions. The IEA solar heating and solar cooling programme is described

  12. 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.

  13. Free convection flow of some fractional nanofluids over a moving vertical plate with uniform heat flux and heat source

    Science.gov (United States)

    Azhar, Waqas Ali; Vieru, Dumitru; Fetecau, Constantin

    2017-08-01

    Free convection flow of some water based fractional nanofluids over a moving infinite vertical plate with uniform heat flux and heat source is analytically and graphically studied. Exact solutions for dimensionless temperature and velocity fields, Nusselt numbers, and skin friction coefficients are established in integral form in terms of modified Bessel functions of the first kind. These solutions satisfy all imposed initial and boundary conditions and reduce to the similar solutions for ordinary nanofluids when the fractional parameters tend to one. Furthermore, they reduce to the known solutions from the literature when the plate is fixed and the heat source is absent. The influence of fractional parameters on heat transfer and fluid motion is graphically underlined and discussed. The enhancement of heat transfer in such flows is higher for fractional nanofluids in comparison with ordinary nanofluids. Moreover, the use of fractional models allows us to choose the fractional parameters in order to get a very good agreement between experimental and theoretical results.

  14. An MHD heat source based on intermetallic reactions

    Energy Technology Data Exchange (ETDEWEB)

    Sadjian, H.; Zavitsanos, P. (General Sciences, Inc., Souderton, PA (United States)); Marston, C.H. (Villanova Univ., PA (United States))

    1991-05-06

    The main objective of this program was the development of an MHD heat source of potential use in Space - Based Multi Megawatt, MHD Power Systems. The approach is based on extension of high temperature chemical/ion release technology developed by the General Sciences, Incorporated (GSI) team and successfully applied in other Space Applications. Solid state reactions have been identified which can deliver energy densities and electrons in excess of those from high energy explosives as well as other conventional fuels. The use of intermetallic reactions can be used to generate hot hydrogen plasma from the reaction, to create a high level of seedant ionization, can be packaged as a cartridge type fuels for discrete pulses. The estimated weight for energizing a (100 MW - 1000 sec) Pulsed MHD Power System can range from 12 to 25 {times} 10{sup 3} kg depending on reaction system and strength of the magnetic field. The program consisted of two major tasks with eight subtasks designed to systematically evaluate these concepts in order to reduce fuel weight requirements. Laboratory measurements on energy release, reaction product identification and levels of ionization were conducted in the first task to screen candidate fuels. The second task addressed the development of a reaction chamber in which conductivity, temperature and pressure were measured. Instrumentation was developed to measure these parameters under high temperature pulsed conditions in addition to computer programs to reduce the raw data. Measurements were conducted at GSI laboratories for fuel weights of up to 120 grams and at the Franklin Research Center* for fuel weights up to 1 kilogram. The results indicate that fuel weight can be scaled using modular packaging. Estimates are presented for fuel weight requirements. 15 refs.

  15. SAFETY

    CERN Multimedia

    Niels Dupont

    2013-01-01

    CERN Safety rules and Radiation Protection at CMS The CERN Safety rules are defined by the Occupational Health & Safety and Environmental Protection Unit (HSE Unit), CERN’s institutional authority and central Safety organ attached to the Director General. In particular the Radiation Protection group (DGS-RP1) ensures that personnel on the CERN sites and the public are protected from potentially harmful effects of ionising radiation linked to CERN activities. The RP Group fulfils its mandate in collaboration with the CERN departments owning or operating sources of ionising radiation and having the responsibility for Radiation Safety of these sources. The specific responsibilities concerning "Radiation Safety" and "Radiation Protection" are delegated as follows: Radiation Safety is the responsibility of every CERN Department owning radiation sources or using radiation sources put at its disposition. These Departments are in charge of implementing the requi...

  16. The design features and safety concepts of the nuclear heating reactor developed in China

    International Nuclear Information System (INIS)

    Zheng Wenxiang; Wang Dazhong

    1995-01-01

    Based on the specific conditions of the nuclear heat applications and the development objectives of the advanced reactors, the nuclear heating reactor (NHR) exploited in China has adhered to the new safety concepts and been designed with a number of advanced features, including the integrated arrangement, full power natural circulation capacity, self-pressurized performance, dynamically-hydraulic control rod drive and passive safety systems, so that higher standard of safety as well as simplification in the plant systems and improvement in economic viability has been achieved. This paper describes the special consideration in the design as well as the main design features and safety concepts of the NHR. Some experimental and analytical results are also presented to demonstrate the NHR safety features

  17. Geothermal energy: the earth, source of heat and electric power

    International Nuclear Information System (INIS)

    Lenoir, D.

    2005-01-01

    This document provides information on the geothermal energy. It presents the different types of geothermal deposits (very low, low and medium energy geothermal energy), the french deposits and the heat production. The electric power production from the geothermal energy is also discussed with the example of Soultz-sous-Forets. The last part deals with the heat pumps. (A.L.B.)

  18. Measured Performance of a Low Temperature Air Source Heat Pump

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, R. K. [Johnson Research LLC, Pueblo West, CO (United States)

    2013-09-01

    A 4-ton Low Temperature Heat Pump (LTHP) manufactured by Hallowell International was installed in a residence near New Haven, Connecticut and monitored over two winters of operation. After attending to some significant service issues, the heat pump operated as designed. This report should be considered a review of the dual compressor 'boosted heat pump' technology. The Low Temperature Heat Pumpsystem operates with four increasing levels of capacity (heat output) as the outdoor temperature drops. The system was shown to select capacity correctly, supplying the appropriate amount of heat to the house across the full range of outdoor temperatures. The system's Coefficient of Performance (Seasonal COP, or SCOP) over two entire winters was calculated, based on measured data, to be 3.29over the first winter and 2.68 over the second winter. A second seasonal efficiency calculation by a different method yielded a SCOP of 2.78 for the first winter and 2.83 for the second winter. This second seasonal efficiency calculation was determined by comparing measured heat pump energy use to the in situ energy use with resistance heat alone. This method is the ratio of the slopes of thedaily energy use load lines.

  19. 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

  20. Thermal Analysis of a Cracked Half-plane under Moving Point Heat Source

    Directory of Open Access Journals (Sweden)

    He Kuanfang

    2017-09-01

    Full Text Available The heat conduction in half-plane with an insulated crack subjected to moving point heat source is investigated. The analytical solution and the numerical means are combined to analyze the transient temperature distribution of a cracked half-plane under moving point heat source. The transient temperature distribution of the half plane structure under moving point heat source is obtained by the moving coordinate method firstly, then the heat conduction equation with thermal boundary of an insulated crack face is changed to singular integral equation by applying Fourier transforms and solved by the numerical method. The numerical examples of the temperature distribution on the cracked half-plane structure under moving point heat source are presented and discussed in detail.

  1. Correct safety requirements during the life cycle of heating plants; Korrekta saekerhetskrav under vaermeanlaeggningars livscykel

    Energy Technology Data Exchange (ETDEWEB)

    Tegehall, Jan; Hedberg, Johan [Swedish National Testing and Research Inst., Boraas (Sweden)

    2006-10-15

    The safety of old steam boilers or hot water generators is in principle based on electromechanical components which are generally easy to understand. The use of safety-PLC is a new and flexible way to design a safe system. A programmable system offers more degrees of freedom and consequently new problems may arise. As a result, new standards which use the Safety Integrity Level (SIL) concept for the level of safety have been elaborated. The goal is to define a way of working to handle requirements on safety in control systems of heat and power plants. SIL-requirements are relatively new within the domain and there is a need for guidance to be able to follow the requirements. The target of this report is the people who work with safety questions during new construction, reconstruction, or modification of furnace plants. In the work, the Pressure Equipment Directive, 97/23/EC, as well as standards which use the SIL concept have been studied. Additionally, standards for water-tube boilers have been studied. The focus has been on the safety systems (safety functions) which are used in water-tube boilers for heat and power plants; other systems, which are parts of these boilers, have not been considered. Guidance has been given for the aforementioned standards as well as safety requirements specification and risk analysis. An old hot water generator and a relatively new steam boiler have been used as case studies. The design principles and safety functions of the furnaces have been described. During the risk analysis important hazards were identified. A method for performing a risk analysis has been described and the appropriate content of a safety requirements specification has been defined. If a heat or power plant is constructed, modified, or reconstructed, a safety life cycle shall be followed. The purpose of the safety life cycle is to plan, describe, document, perform, check, test, and validate that everything is correctly done. The components of the safety

  2. Recovery Act: Tennessee Energy Efficient Schools Initiative Ground Source Heat Pump Program

    Energy Technology Data Exchange (ETDEWEB)

    Townsend, Terry [Townsend Engineering, Inc., Davenport, IA (United States); Slusher, Scott [Townsend Engineering, Inc., Davenport, IA (United States)

    2017-04-24

    The Tennessee Energy Efficient Schools Initiative (EESI) Hybrid-Water Source Heat Pump (HY-GSHP) Program sought to provide installation costs and operation costs for different Hybrid water source heat pump systems’ configurations so that other State of Tennessee School Districts will have a resource for comparison purposes if considering a geothermal system.

  3. Modeling and analysis of a transcritical rankine power cycle with a low grade heat source

    DEFF Research Database (Denmark)

    Nguyen, Chan; Veje, Christian

    efficiency, exergetic efficiency and specific net power output. A generic cycle configuration has been used for analysis of a geothermal energy heat source. This model has been validated against similar calculations using industrial waste heat as the energy source. Calculations are done with fixed...

  4. Design and modelling of a novel compact power cycle for low temperature heat sources

    DEFF Research Database (Denmark)

    Wronski, Jorrit; Skovrup, Morten Juel; Elmegaard, Brian

    2012-01-01

    Power cycles for the efficient use of low temperature heat sources experience increasing attention. This paper describes an alternative cycle design that offers potential advantages in terms of heat source exploitation. A concept for a reciprocating expander is presented that performs both, work ...

  5. Optimum load distribution between heat sources based on the Cournot model

    Science.gov (United States)

    Penkovskii, A. V.; Stennikov, V. A.; Khamisov, O. V.

    2015-08-01

    One of the widespread models of the heat supply of consumers, which is represented in the "Single buyer" format, is considered. The methodological base proposed for its description and investigation presents the use of principles of the theory of games, basic propositions of microeconomics, and models and methods of the theory of hydraulic circuits. The original mathematical model of the heat supply system operating under conditions of the "Single buyer" organizational structure provides the derivation of a solution satisfying the market Nash equilibrium. The distinctive feature of the developed mathematical model is that, along with problems solved traditionally within the bounds of bilateral relations of heat energy sources-heat consumer, it considers a network component with its inherent physicotechnical properties of the heat network and business factors connected with costs of the production and transportation of heat energy. This approach gives the possibility to determine optimum levels of load of heat energy sources. These levels provide the given heat energy demand of consumers subject to the maximum profit earning of heat energy sources and the fulfillment of conditions for formation of minimum heat network costs for a specified time. The practical realization of the search of market equilibrium is considered by the example of a heat supply system with two heat energy sources operating on integrated heat networks. The mathematical approach to the solution search is represented in the graphical form and illustrates computations based on the stepwise iteration procedure for optimization of levels of loading of heat energy sources (groping procedure by Cournot) with the corresponding computation of the heat energy price for consumers.

  6. Work safety of farmers and heating entrepreneurs in 2008; Tyoeturvallisuus bioenergian tuotannossa maatiloilla

    Energy Technology Data Exchange (ETDEWEB)

    Lauhanen, R.; Suojaranta, J.; Raety, H.; Petaeinen, J.

    2009-07-01

    There were at least 327 heating entrepreneurs responsible for fuel procurement and heating production in Finland at the end of 2007 according to TTS Research. Recently, the expansion of bio energy business has become a large one. This new business, however, may contain many risks, too. There have been discussions on the well-being and work safety of heating entrepreneurs and farmers in the South Ostrobothnia. In order to avoid the occupational risks and accidents of farmers and heating entrepreneurs, this study aimed at finding out the occupational risks and work safety of this target group. The study was funded by the Work safety funds of the Finnish Mela organization (http://www.mela.fi) and by Seinaejoki University of Applied Sciences /http://seamk.fi). A questionnaire for 328 farmers and heating entrepreneurs was carried out in the spring 2008. In addition, study visits to ten sampled heating plants in South Ostrobothnia were carried out. The farmers and heating entrepreneurs were interviewed and the work conditions were measured and determined on the heating plants with the maximal effectiveness of 1 MW. Domestic renewable forest energy is a possibility in the rural areas of Finland. The heating entrepreneurs and farmers used to be in a hurry according to questionnaires. The weak profitability and the changing bio energy policies were problems in the heating entrepreneurship. The occupational accidents had occured, especially, in energy-wood logging operations and when fuel wood was prepared mechanically. Occupational accidents had also occured in the repairing of forest machines, chippers and trucks, and in the repairing of the heating plant facilities. The passageways of the heating plants should be planned more carefully according to the interviews. The loud of 64-81 dB, the mean temperature of 28,3 Celsius degrees and mean air humidity of 26% were measured in the investigated heating plants. Especially, advice and training in safe energy wood logging will

  7. Beam heat load investigations with a cold vacuum chamber for diagnostics in a synchrotron light source

    Energy Technology Data Exchange (ETDEWEB)

    Voutta, Robert

    2016-04-22

    The beam heat load is a crucial input parameter for the cryogenic design of superconducting insertion devices. To understand the discrepancies between the predicted heat load of an electron beam to a cold bore and the heat load observed in superconducting devices, a cold vacuum chamber for diagnostics has been built. Extensive beam heat load measurements were performed at the Diamond light source. They are analysed systematically and combined with complementary impedance bench measurements.

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

    OpenAIRE

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

    2018-01-01

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

  9. EFFECT OF THE TYPE OF HEAT SOURCES ON CARBON DIOXIDE EMISSIONS

    Directory of Open Access Journals (Sweden)

    Sławomir Rabczak

    2016-11-01

    Full Text Available A lot of attention is nowadays devoted to the problem of generally defined ecology. It is absolutely essential in case of systems and sources generating heat due to their direct influence on the environment through emitting post-process products to the atmosphere which are, most frequently a result of combustion. Therefore, constant searchers are made to optimize the operation of heat sources and to acquire energy from sources for which the general balance of carbon dioxide emission is zero or close to zero. This work compares the emissions of equivalent CO2 from selected systems with the following heat sources: coal, gas furnace, heat pump, and refers results of the analysis to aspects connected with regulations concerning environmental protection. The systems generating thermal energy in the gas furnaces, coal, biomass, as well as the compression heat pumps with the lower heat source as ambient air or ground were taken under consideration, as well as centralized systems for the production of heat based on the combustion of coal, gas, oil, and biomass. the Emission of carbon dioxide for the installation of cogeneration and absorption heat pump were also calculated. Similarly obtained amount of extra emission necessary for the proper operation maintenance of heating devices via the supplied electricity from external source, the mostly fuel-fired power plants for fuels as previously mentioned. The results of the calculations were presented in tables and graphs.

  10. Ground-Coupling with Water Source Heat Pumps

    Energy Technology Data Exchange (ETDEWEB)

    Kavanaugh, S.

    0001-01-01

    Ground-coupled heat pumps (GCHPs) have been receiving increasing attention in recent years. In areas where the technology has been properly applied, they are the system of choice because of their reliability, high level of comfort, low demand, and low operating costs. Initially these systems were most popular in rural, residential applications where heating requirements were the primary consideration. However, recent improvements in heat pumps units and installation procedures have expanded the market to urban and commercial applications. This paper discusses some of the current activity in the commercial sector. The basic system and nomenclature are discussed. Several variations for commercial buildings are presented along with examples of systems in operation. Several advantages and disadvantages are listed. Operating and installation costs are briefly discussed. Finally, the GCHP is presented as an alternative that is able to counter much of the criticism leveled by the natural gas industry toward conventional heat pumps.

  11. Ground-Coupling with Water Source Heat Pumps

    Energy Technology Data Exchange (ETDEWEB)

    Kavanaugh, S

    0000-12-30

    Ground-coupled heat pumps (GCHPs) have been receiving increasing attention in recent years. In areas where the technology has been properly applied, they are the system of choice because of their reliability, high level of comfort, low demand, and low operating costs. Initially these systems were most popular in rural, residential applications where heating requirements were the primary consideration. However, recent improvements in heat pumps units and installation procedures have expanded the market to urban and commercial applications. This paper discusses some of the current activity in the commercial sector. The basic system and nomenclature are discussed. Several variations for commercial buildings are presented along with examples of systems in operation. Several advantages and disadvantages are listed. Operating and installation costs are briefly discussed. Finally, the GCHP is presented as an alternative that is able to counter much of the criticism leveled by the natural gas industry toward conventional heat pumps.

  12. Safety study on nuclear heat utilization system - accident delineation and assessment on nuclear steelmaking pilot plant

    International Nuclear Information System (INIS)

    Yoshida, T.; Mizuno, M.; Tsuruoka, K.

    1982-01-01

    This paper presents accident delineation and assessment on a nuclear steelmaking pilot plant as an example of nuclear heat utilization systems. The reactor thermal energy from VHTR is transported to externally located chemical process plant employing helium-heated steam reformer by an intermediate heat transport loop. This paper on the nuclear steelmaking pilot plant will describe (1) system transients under accident conditions, (2) impact of explosion and fire on the nuclear reactor and the public and (3) radiation exposure on the public. The results presented in this paper will contribute considerably to understanding safety features of nuclear heat utilization system that employs the intermediate heat transport loop and the helium-heated steam reformer

  13. Process for adapting a heat source and a thermal machine by temporary heat storage

    International Nuclear Information System (INIS)

    Cahn, R.P.; Nicholson, E.W.

    1975-01-01

    The process described is intended to ensure the efficient use of the heat from a nuclear reactor or from a furnace burning fossil fuel at constant power, and of a boiler in a power station comprising a multi-stage steam turbine, the steam extracted from the turbine being used for pre-heating the boiler feed water. This process is most flexible with a varying load. It includes the high temperature storage of the excess heat energy in a low vapor pressure storage liquid (hydrocarbon oils, molten salts or liquid metals) at atmospheric pressure when the demand is low; then, when the energy demand is at its height, the reduction of steam extraction from the turbine with simultaneous utilisation of the hot heat storage liquid for the various maintenance heating functions of the power station by heat exchange, so that the heat can expand totally in the turbine with generation of energy [fr

  14. Annual investigation of vertical type ground source heat pump system performance on a wall heating and cooling system in Istanbul

    Energy Technology Data Exchange (ETDEWEB)

    Akbulut, U.; Yoru, Y.; Kincay, O. [Department of Mechanical Engineering, Yildiz Technical University (Turkey)], email: akbulutugur@yahoo.com, email: yilmazyoru@gmail.com, email: okincay@yildiz.edu.tr

    2011-07-01

    Wall heating and cooling systems (WHCS) are equipped with heating serpentines or panels for water circulation. These systems operate in a low temperature range so they are preferable to other, conventional systems. Furthermore, when these systems are connected to a ground source heat pump (GSHP) system, energy performance and thermal comfort are further enhanced. The purpose of this paper is to report the results of an annual inspection done on a vertical type ground-coupled heat pump systems (V-GSHP) WHCS in Istanbul and present the results. The performance data from the Yildiz Renewable Energy House at Davutpasa Campus of Yildiz Technical University, Istanbul, Turkey, during the year 2010 were collected and analyzed. The conclusions drawn from the inspection and analysis were listed in this paper. Using renewable energy sources effectively will bring both economic and environmental benefits and it is hoped that the use of these energy efficient WHCS systems will become widespread.

  15. STAR: The Secure Transportable Autonomous Reactor System - Encapsulated Fission Heat Source

    International Nuclear Information System (INIS)

    Ehud Greenspan

    2003-01-01

    OAK-B135 The Encapsulated Nuclear Heat Source (ENHS) is a novel 125 MWth fast spectrum reactor concept that was selected by the 1999 DOE NERI program as a candidate ''Generation-IV'' reactor. It uses Pb-Bi or other liquid-metal coolant and is intended to be factory manufactured in large numbers to be economically competitive. It is anticipated to be most useful to developing countries. The US team studying the feasibility of the ENHS reactor concept consisted of the University of California, Berkeley, Argonne National Laboratory (ANL), Lawrence Livermore National Laboratory (LLNL) and Westinghouse. Collaborating with the US team were three Korean organizations: Korean Atomic Energy Research Institute (KAERI), Korean Advanced Institute for Science and Technology (KAIST) and the University of Seoul, as well as the Central Research Institute of the Electrical Power Industry (CRIEPI) of Japan. Unique features of the ENHS include at least 20 years of operation without refueling; no fuel handling in the host country; no pumps and valves; excess reactivity does not exceed 1$; fully passive removal of the decay heat; very small probability of core damaging accidents; autonomous operation and capability of load-following over a wide range; very long plant life. In addition it offers a close match between demand and supply, large tolerance to human errors, is likely to get public acceptance via demonstration of superb safety, lack of need for offsite response, and very good proliferation resistance. The ENHS reactor is designed to meet the requirements of Generation IV reactors including sustainable energy supply, low waste, high level of proliferation resistance, high level of safety and reliability, acceptable risk to capital and, hopefully, also competitive busbar cost of electricity

  16. An analysis of the vapor flow and the heat conduction through the liquid-wick and pipe wall in a heat pipe with single or multiple heat sources

    Science.gov (United States)

    Chen, Ming-Ming; Faghri, Amir

    1990-01-01

    A numerical analysis is presented for the overall performance of heat pipes with single or multiple heat sources. The analysis includes the heat conduction in the wall and liquid-wick regions as well as the compressibility effect of the vapor inside the heat pipe. The two-dimensional elliptic governing equations in conjunction with the thermodynamic equilibrium relation and appropriate boundary conditions are solved numerically. The solutions are in agreement with existing experimental data for the vapor and wall temperatures at both low and high operating temperatures.

  17. Ground source geothermal heat. Ground source heat pumps and underground thermal energy storage systems. Proceedings; Oberflaechennahe Geothermie. Erdgekoppelte Waermepumpen und unterirdische thermische Energiespeicher. Tagungsband

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    At the ninth international user forum on shallow geothermal heat on 28th and 29th April, 2009, at BadStaffelstein (Federal Republic of Germany), the following lectures were held: (1) Information system on shallow geothermal heat for Bavaria (Marcellus Schulze); (2) Calculation of the spreading of temperature anomalies in groundwater as an instrument of planning of heat pump systems (Wolfgang Rauch); (3) Comparison of models for simulation of deep geothermal probes (Markus Proell); (4) Impact of the geometry of boreholes and probes on heat transport (Manfred Reuss); (5) Thermal respond tests and temperature depth profiles - Experience from research and practice (Markus Kuebert); (6) A model of simulation for the investigation of the impact of different heat transfer fluids on the efficiency of ground source heat pump devices (Roland Koenigsdorff); (7) The research project EWSplus - Investigations for quality assurance of geothermal probes (Mathieu Riegger); (8) Quality management of plants for the utilization of shallow geothermal heat with geothermal probes - the example of Baden-Wuerttemberg (Bruno Lorinser, Ingrid Stober); (9) Not every heat pump contributes to climate protection (Falk Auer); (10) Field measurements of heat pumps in residential buildings with modern standard and in older buildings (Marek Miara); (11) System technology for a great annual performance factor (Werner Schenk); (12) Modification of older geothermal heat probe devices for use with modern heat pumps (Klaus Friedrich Staerk); (13) Energy-efficient modernisation of a pensioners' condominium from the 1970s with solar-geothermal-air (Michael Guigas); (14) Evaluation and optimization of operation of seasonal storage systems in the foundations of office buildings (Herdis Kipry); (15) Evaluation of an innovative heating and cooling concept with rain water vessels, thermo-active building components and phase change materials in a residential building (Doreen Kalz); (16) Contracts for ground

  18. Heating with ice. Efficient heating source for heat pumps. Primary source storage. Alternative to soil sensors and soil collectors; Heizen mit Eis. Effiziente Waermequelle fuer Waermepumpen. Primaerquellenspeicher, Alternative zu Erdsonden und Erdkollektoren

    Energy Technology Data Exchange (ETDEWEB)

    Tippelt, Egbert [Viessmann, Allendorf (Germany)

    2011-12-15

    For several years heat pumps have taken up a fixed place in the mix of annually installed thermal generators. Thus, in the year 2010 every tenth newly installed heater was a heat pump. A new concept for the development and utilization of natural heat now makes this technology even more attractive. From this perspective, the author of the contribution under consideration reports on a SolarEis storage. This SolarEis storage consists of a cylindrical concrete tank with two heat exchangers consiting of plastic pipes. The SolarEis storage uses outdoor air, solar radiation and soil as heat sources for brine / water heat pumps simultaneously.

  19. A thermoacoustic engine capable of utilizing multi-temperature heat sources

    International Nuclear Information System (INIS)

    Qiu Limin; Wang Bo; Sun Daming; Liu Yu; Steiner, Ted

    2009-01-01

    Low-grade energy is widespread. However, it cannot be utilized with high thermal efficiency directly. Following the principle of thermal energy cascade utilization, a thermoacoustic engine (TE) with a new regenerator that can be driven by multiple heat sources at different temperature levels is proposed. Taking a regenerator that utilizes heat sources at two temperatures as an example, theoretical research has been conducted on a traveling-wave TE with the new regenerator to predict its performance. Experimental verification is also done to demonstrate the benefits of the new regenerator. Results indicate that a TE with the new regenerator utilizing additional heat at a lower temperature experiences an increase in pressure ratio, acoustic power, efficiency, and exergy efficiency with proper heat input at an appropriate temperature at the mid-heater. A regenerator that uses multi-temperature heat sources can provide a means of recovering lower grade heat.

  20. Elastic unloading of a disk after plastic deformation by a circular heat source

    International Nuclear Information System (INIS)

    Gamer, U.; Mack, W.

    1987-01-01

    Subject of the investigation is the transient stress distribution in an elastic-plastic disk acted upon by a circular heat source. The disk serves as a mechanical model of the rotating anode of an X-ray-tube. The calculation is based on Tresca's yield criterion and the flow rule associatd to it. During heating, a plastic region spreads around the source, which is absorbed by an unloaded zone after the removal of the source. (orig.) [de

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

    Directory of Open Access Journals (Sweden)

    Xiang Gou

    2016-12-01

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

  2. Performance analysis on a large scale borehole ground source heat pump in Tianjin cultural centre

    Science.gov (United States)

    Yin, Baoquan; Wu, Xiaoting

    2018-02-01

    In this paper, the temperature distribution of the geothermal field for the vertical borehole ground-coupled heat pump was tested and analysed. Besides the borehole ground-coupled heat pump, the system composed of the ice storage, heat supply network and cooling tower. According to the operation data for nearly three years, the temperature constant zone is in the ground depth of 40m -120m with a temperature gradient of about 3.0°C/100m. The temperature of the soil dropped significantly in the heating season, increased significantly in the cooling season, and reinstated in the transitional season. With the energy balance design of the heating and cooling and the existence of the soil thermal inertia, the soil temperature stayed in a relative stable range and the ground source heat pump system was operated with a relative high efficiency. The geothermal source heat pump was shown to be applicable for large scale utilization.

  3. What Can We Learn about Workplace Heat Stress Management from a Safety Regulator Complaints Database?

    Science.gov (United States)

    Hansen, Alana; Pisaniello, Dino; Varghese, Blesson; Rowett, Shelley; Hanson-Easey, Scott; Bi, Peng; Nitschke, Monika

    2018-03-06

    Heat exposure can be a health hazard for many Australian workers in both outdoor and indoor situations. With many heat-related incidents left unreported, it is often difficult to determine the underlying causal factors. This study aims to provide insights into perceptions of potentially unsafe or uncomfortably hot working conditions that can affect occupational health and safety using information provided by the public and workers to the safety regulator in South Australia (SafeWork SA). Details of complaints regarding heat exposure to the regulator's "Help Centre" were assembled in a dataset and the textual data analysed thematically. The findings showed that the majority of calls relate to indoor work environments such as kitchens, factories, and warehouses. The main themes identified were work environment, health effects, and organisational issues. Impacts of hot working conditions ranged from discomfort to serious heat-related illnesses. Poor management practices and inflexibility of supervisors featured strongly amongst callers' concerns. With temperatures predicted to increase and energy prices escalating, this timely study, using naturalistic data, highlights accounts of hot working conditions that can compromise workers' health and safety and the need for suitable measures to prevent heat stress. These could include risk assessments to assess the likelihood of heat stress in workplaces where excessively hot conditions prevail.

  4. What Can We Learn about Workplace Heat Stress Management from a Safety Regulator Complaints Database?

    Directory of Open Access Journals (Sweden)

    Alana Hansen

    2018-03-01

    Full Text Available Heat exposure can be a health hazard for many Australian workers in both outdoor and indoor situations. With many heat-related incidents left unreported, it is often difficult to determine the underlying causal factors. This study aims to provide insights into perceptions of potentially unsafe or uncomfortably hot working conditions that can affect occupational health and safety using information provided by the public and workers to the safety regulator in South Australia (SafeWork SA. Details of complaints regarding heat exposure to the regulator’s “Help Centre” were assembled in a dataset and the textual data analysed thematically. The findings showed that the majority of calls relate to indoor work environments such as kitchens, factories, and warehouses. The main themes identified were work environment, health effects, and organisational issues. Impacts of hot working conditions ranged from discomfort to serious heat-related illnesses. Poor management practices and inflexibility of supervisors featured strongly amongst callers’ concerns. With temperatures predicted to increase and energy prices escalating, this timely study, using naturalistic data, highlights accounts of hot working conditions that can compromise workers’ health and safety and the need for suitable measures to prevent heat stress. These could include risk assessments to assess the likelihood of heat stress in workplaces where excessively hot conditions prevail.

  5. Radiogenic heat production and the earth's heat balance. A source of arguments in geoscience

    International Nuclear Information System (INIS)

    Kuczera, B.

    2008-01-01

    The terrestrial heat flow into interstellar space amounts to approx. 32 TW on the basis of an average heat flow density of 63 mW per sq.m. of earth surface. The loss flow derives part of the energy from the residual heat of the nascent phase of the earth (approx. 40%) and the other part from the natural disintegration of longlived radionuclides, i.e. radiogenic heat production (roughly 60%). This concept met with broad consensus in the geosciences until the 1980s. In 1993, Pollack et al. concluded from the evaluation of recent measured data that heat loss via the oceanic crust of the earth was clearly higher, which raises the loss flow to a total of 44 TW. This is contradicted by Hoffmeister and Criss, who conclude from a modified geochemical model that the total heat loss of 31 TW is fully compensated by radiogenic heat production. In 2001, C. Herndon introduced a new idea into the discussion. According to his thesis, planetary differentiation caused a nuclear georeactor to be created in the center of the earth, whose continuous thermal power of approx. 3 TW contributes to compensating heat losses. Physicists and geoscientists hope to be able to derive new findings on this thesis and on the distribution of radiogenic heat production in the interior of the earth from the planned geo-neutrino experiment in Homestake, USA. (orig.)

  6. Comprehensive thermodynamic analysis of a renewable energy sourced hybrid heating system combined with latent heat storage

    International Nuclear Information System (INIS)

    Utlu, Zafer; Aydın, Devrim; Kıncay, Olcay

    2014-01-01

    Highlights: • An experimental thermal investigation of hybrid renewable heating system is presented. • Analyses were done by using real data obtained from a prototype structure. • Exergy efficiency of system components investigated during discharging period are close to each other as 32%. • The average input energy and exergy rates to the LHS were 0.770 and 0.027 kW. • Overall total energy and exergy efficiencies of LHS calculated as 72% and 28.4%. - Abstract: In this study an experimental thermal investigation of hybrid renewable heating system is presented. Latent heat storage stores energy, gained by solar collectors and supplies medium temperature heat to heat pump both day time also night time while solar energy is unavailable. In addition to this an accumulation tank exists in the system as sensible heat storage. It provides supply–demand balance with storing excess high temperature heat. Analyses were done according to thermodynamic’s first and second laws by using real data obtained from a prototype structure, built as part of a project. Results show that high percent of heat loses took place in heat pump with 1.83 kW where accumulator-wall heating cycle followed it with 0.42 kW. Contrarily highest break-down of exergy loses occur accumulator-wall heating cycle with 0.28 kW. Averagely 2.42 kW exergy destruction took place in whole system during the experiment. Solar collectors and heat pump are the promising components in terms of exergy destruction with 1.15 kW and 1.09 kW respectively. Exergy efficiency of system components, investigated during discharging period are in a close approximately of 32%. However, efficiency of solar collectors and charging of latent heat storage are 2.3% and 7% which are relatively low. Average overall total energy and exergy efficiencies of latent heat storage calculated as 72% and 28.4% respectively. Discharging energy efficiency of latent heat storage is the highest through all system components. Also heat

  7. Effect of the Presence of Semi-circular Cylinders on Heat Transfer From Heat Sources Placed in Two Dimensional Channel

    Directory of Open Access Journals (Sweden)

    Ahmed W. Mustava

    2013-04-01

    Full Text Available The effect of a semi-circular cylinders in a two dimensional channel on heat transfer by forced convection from two heat sources with a constant temperature has been studied numerically. Each channel contains two heat sources; one on the upper surface of the channel and the other on the lower surface of the channel. There is semi-circular cylinder under the source in upper surface and there is semi-circular cylinder above the source in lower surface. The location of the second heat source with its semi-cylinder has been changed and keeps the first source with its semi- cylinder at the same location. The flow and temperature field are studied numerically with different values of Reynolds numbers and for different spacing between the centers of the semi-cylinders. The laminar flow field is analyzed numerically by solving the steady forms of the two-dimensional incompressible Navier- Stokes and energy equations.  The Cartesian velocity components and pressure on a collocated (non-staggered grid are used as dependent variables in the momentum equations, which discretized by finite volume method, body fitted coordinates are used to represent the complex channel geometry accurately, and grid generation technique based on elliptic partial differential equations is employed. SIMPLE algorithm is used to adjust the velocity field to satisfy the conservation of mass.  The range of Reynolds number is (Re= 100 – 800 and the range of the spacing between the semi-cylinders is(1-4 and the Prandtl number is 0.7.The results showed that increasing the spacing between the semi-cylinders increases the average of Nusselt number of the first heat source for all Reynolds numbers. As well as the results show that the best case among the cases studied to enhance the heat transfer is when the second heat source and its semi-cylinder located on at the distance (S=1.5 from the first half of the cylinder and the Reynolds number is greater than (Re ≥ 400 because of the

  8. Heat source reconstruction from noisy temperature fields using an optimised derivative Gaussian filter

    Science.gov (United States)

    Delpueyo, D.; Balandraud, X.; Grédiac, M.

    2013-09-01

    The aim of this paper is to present a post-processing technique based on a derivative Gaussian filter to reconstruct heat source fields from temperature fields measured by infrared thermography. Heat sources can be deduced from temperature variations thanks to the heat diffusion equation. Filtering and differentiating are key-issues which are closely related here because the temperature fields which are processed are unavoidably noisy. We focus here only on the diffusion term because it is the most difficult term to estimate in the procedure, the reason being that it involves spatial second derivatives (a Laplacian for isotropic materials). This quantity can be reasonably estimated using a convolution of the temperature variation fields with second derivatives of a Gaussian function. The study is first based on synthetic temperature variation fields corrupted by added noise. The filter is optimised in order to reconstruct at best the heat source fields. The influence of both the dimension and the level of a localised heat source is discussed. Obtained results are also compared with another type of processing based on an averaging filter. The second part of this study presents an application to experimental temperature fields measured with an infrared camera on a thin plate in aluminium alloy. Heat sources are generated with an electric heating patch glued on the specimen surface. Heat source fields reconstructed from measured temperature fields are compared with the imposed heat sources. Obtained results illustrate the relevancy of the derivative Gaussian filter to reliably extract heat sources from noisy temperature fields for the experimental thermomechanics of materials.

  9. Transition to chaos in a square enclosure containing internal heat sources

    Energy Technology Data Exchange (ETDEWEB)

    Baytas, A.C. [Institute For Nuclear Energy, Istanbul (Turkey)

    1995-09-01

    A numerical investigation is performed to study the transition from steady to chaotic flow of a fluid confined in a two-dimensional square cavity. The cavity has rigid walls of constant temperature containing uniformly distributed internal heat source. Effects of the Rayleigh number of flow and heat transfer rates are studied. In addition to, same problem is solved for sinusoidally changing internal heat source to show its effect on the flow model and heat transfer of the enclosures. Details of oscillatory solutions and flow bifurcations are presented.

  10. Current status of ground source heat pumps and underground thermal energy storage in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Sanner, B. [Justus Liebig University, Giessen (Germany). Institute of Applied Geosciences; Karytsas, C.; Mendrinos, D. [Center for Renewable Energy Sources, Pikermi (Greece); Rybach, L. [Geowatt AG, Zurich (Switzerland)

    2003-12-01

    Geothermal Heat Pumps, or Ground Coupled Heat Pumps (GCHP), are systems combining a heat pump with a ground heat exchanger (closed loop systems), or fed by ground water from a well (open loop systems). They use the earth as a heat source when operating in heating mode, with a fluid (usually water or a water-antifreeze mixture) as the medium that transfers the heat from the earth to the evaporator of the heat pump, thus utilising geothermal energy. In cooling mode, they use the earth as a heat sink. With Borehole Heat Exchangers (BHE), geothermal heat pumps can offer both heating and cooling at virtually any location, with great flexibility to meet any demands. More than 20 years of R and D focusing on BUE in Europe has resulted in a well-established concept of sustainability for this technology, as well as sound design and installation criteria. Recent developments are the Thermal Response Test, which allows in-situ-determination of ground thermal properties for design purposes, and thermally enhanced grouting materials to reduce borehole thermal resistance. For cooling purposes, but also for the storage of solar or waste heat, the concept of underground thermal energy storage (UTES) could prove successful. Systems can be either open (aquifer storage) or can use BHE (borehole storage). Whereas cold storage is already established on the market, heat storage, and, in particular, high temperature heat storage (> 50{sup o}C) is still in the demonstration phase. Despite the fact that geothermal heat pumps have been in use for over 50 years now (the first were in the USA), market penetration of this technology is still in its infancy, with fossil fuels dominating the space heating market and air-to-air heat pumps that of space cooling. In Germany, Switzerland, Austria, Sweden, Denmark, Norway, France and the USA, large numbers of geothermal heat pumps are already operational, and installation guidelines, quality control and contractor certification are now major issues

  11. Link between intermittent electrical energy sources and district heating sector

    DEFF Research Database (Denmark)

    Dominkovic, Dominik Franjo

    2016-01-01

    Energy has always been one of the key challenges in planning of societies' development worldwide. The COP conference in Paris in December 2015 has shown unprecedented mutual understanding of harmful consequences climate change can cause. Integrating power and heating sectors in an efficient way...

  12. Hydrogen and renewable energy sources integrated system for greenhouse heating

    Directory of Open Access Journals (Sweden)

    Ileana Blanco

    2013-09-01

    Full Text Available A research is under development at the Department of Agro- Environmental Sciences of the University of Bari “Aldo Moro” in order to investigate the suitable solutions of a power system based on solar energy (photovoltaic and hydrogen, integrated with a geothermal heat pump for powering a self sustained heated greenhouse. The electrical energy for heat pump operation is provided by a purpose-built array of solar photovoltaic modules, which supplies also a water electrolyser system controlled by embedded pc; the generated dry hydrogen gas is conserved in suitable pressured storage tank. The hydrogen is used to produce electricity in a fuel cell in order to meet the above mentioned heat pump power demand when the photovoltaic system is inactive during winter night-time or the solar radiation level is insufficient to meet the electrical demand. The present work reports some theoretical and observed data about the electrolyzer operation. Indeed the electrolyzer has required particular attention because during the experimental tests it did not show a stable operation and it was registered a performance not properly consistent with the predicted performance by means of the theoretical study.

  13. Interaction of 238PuO2 heat sources with terrestrial and aquatic environments

    International Nuclear Information System (INIS)

    Patterson, J.H.; Nelson, G.B.; Matlack, G.M.; Waterbury, G.R.

    1975-01-01

    Radioisotope thermoelectric generators used in space missions are designed with a great factor of safety to ensure that they will withstand reentry from orbit and impact with the earth, and safely contain the nuclear fuel until it is recovered. Existing designs, utilizing 238 PuO 2 fuel, have proved more than adequately safe. More data about the interaction of this material with terrestrial and aquatic environments is continually being sought to predict the behavior of these heat sources in the extremely unlikely contact of these materials with the land or ocean. Terrestrial environments are simulated with large environmental chambers that permit control of temperature, humidity, and rainfall using different kinds of soils. Rain falling on thermally hot chunks of 238 PuO 2 causes the spallation of the surface of the fuel into extremely fine particles, as small as 50 nm, that are later transported downward through the soil. Some of the plutonia particles become agglomerated with soil particles. Plutonium transport is more significant during winter than during summer because evaporation losses from the soil are less in winter. Aquatic environments are simulated with large aquaria that provide temperature and aeration control. Earlier fuel designs that employed a plutonia-molybdenum cermet showed plutonium release rates of about 10 μCi/m 2 - s, referred to the total surface area of the cermet. Present advanced fuels, employing pure plutonium oxide, show release rates of about 20 nCi/m 2 - s in seawater and about 150 nCi/m 2 - s in freshwater. The temperature of these more advanced heat sources does not seem to affect the release rate in seawater. (auth)

  14. The structural design of the experimental equipment for unconventional heating water using heat transfer surfaces located in the heat source

    Directory of Open Access Journals (Sweden)

    Jandačka J.

    2013-04-01

    Full Text Available Flue gas temperature at throat of most industrially produced fireplaces is around 250 to 350 °C. It's quite interesting thermal potential, which can be even before sucking up the chimney back utilize. One of the potential uses of this device to heat the hot water. Article refers to the structural design of such a device, which works with the transfer of heat through a substance changes phase from liquid to steam in a sealed tube (heat pipe. Benefits of heat pipes is their light weight, the thermal effect of a rapid and low maintenance costs.

  15. The structural design of the experimental equipment for unconventional heating water using heat transfer surfaces located in the heat source

    Science.gov (United States)

    Kaduchová, K.; Lenhard, R.; Gavlas, S.; Jandačka, J.

    2013-04-01

    Flue gas temperature at throat of most industrially produced fireplaces is around 250 to 350 °C. It's quite interesting thermal potential, which can be even before sucking up the chimney back utilize. One of the potential uses of this device to heat the hot water. Article refers to the structural design of such a device, which works with the transfer of heat through a substance changes phase from liquid to steam in a sealed tube (heat pipe). Benefits of heat pipes is their light weight, the thermal effect of a rapid and low maintenance costs.

  16. Barriers for district heating as a source of flexibility for the electricity system

    DEFF Research Database (Denmark)

    Skytte, Klaus; Olsen, Ole Jess; Soysal, Emilie Rosenlund

    2017-01-01

    of wind power. Power-to-heat technologies, electric boilers and heat pumps are blocked by high tariffs and taxes. A calculation of the heat costs of different DH technologies demonstrates that, under the present price and tax conditions in Denmark and Sweden, CHP and power-to-heat are unable to compete......The Scandinavian countries Denmark, Norway and Sweden currently deploy large amounts of variable renewable energy (VRE) sources, especially wind power. This calls for additional flexibility in the power market. The right coupling to the underlying national and local district heating (DH) markets...

  17. Federal Technology Alert: Ground-Source Heat Pumps Applied to Federal Facilities-Second Edition; FINAL

    International Nuclear Information System (INIS)

    Hadley, Donald L

    2001-01-01

    This Federal Technology Alert, which was sponsored by the U.S. Department of Energy's Office of Federal Energy Management Programs, provides the detailed information and procedures that a Federal energy manager needs to evaluate most ground-source heat pump applications. This report updates an earlier report on ground-source heat pumps that was published in September 1995. In the current report, general benefits of this technology to the Federal sector are described, as are ground-source heat pump operation, system types, design variations, energy savings, and other benefits. In addition, information on current manufacturers, technology users, and references for further reading are provided

  18. Analysis of carbon monoxide production in multihundred-watt heat sources

    International Nuclear Information System (INIS)

    Peterson, D.E.; Mulford, R.N.R.

    1976-05-01

    The production of carbon monoxide observed within Multihundred Watt heat sources placed under storage conditions was analyzed. Results of compositional and isotopic analyses of gas taps performed on eight heat sources are summarized and interpreted. Several proposed CO generation mechanisms are examined theoretically and assessed by applying thermodynamic principles. Outgassing of the heat source graphite followed by oxygen isotopic exchange through the vent assemblies appears to explain the CO production at storage temperatures. Reduction of the plutonia fuel sphere by the CO is examined as a function of temperature and stoichiometry. Experiments that could be performed to investigate possible CO generation mechanisms are discussed

  19. Geothermal heat potential - the source for heating greenhouses in Southestern Europe

    Directory of Open Access Journals (Sweden)

    Urbancl Danijela

    2016-01-01

    Full Text Available The paper presents economically evaluated solutions for heating greenhouses with geothermal potential, if the same greenhouse is placed in two different locations in Southeastern Europe, one in Slovenia and the other in Serbia. The direct geothermal water exploitation using heat exchangers is presented and the remaining heat potential of already used geothermal water is exploited using high temperature heat pumps. Energy demands for heating greenhouses are calculated considering climatic parameters of both locations. Furthermore, different constructions materials are taken into account, and energy demands are evaluated if the same greenhouse is made of 4 mm toughened single glass, double insulated glass or polycarbonate plates. The results show that the geothermal energy usage is economically feasible in both locations, because payback periods are in range from two to almost eight years for different scenarios.

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

    Directory of Open Access Journals (Sweden)

    Zhongchao Zhao

    2018-05-01

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

  1. Domestic energy sources urged as Middle East situation heats up

    International Nuclear Information System (INIS)

    Rodgers, L.M.

    1990-01-01

    This article discusses the alternatives to foreign oil as an energy source for the US in the light of the invasion of Kuwait by Iraq. Topics addressed include the responses of organizations representing various energy sources, the public response of the Department of Energy, the response of conservation advocates, and the Administration's reaction

  2. Status of non-electric nuclear heat applications: Technology and safety

    International Nuclear Information System (INIS)

    2000-11-01

    Nuclear energy plays an important role in electricity generation, producing 16% of the world's electricity at the beginning of 1999. It has proven to be safe, reliable, economical and has only a minimal impact on the environment. Most of the world's energy consumption, however, is in the form of heat. The market potential for nuclear heat was recognized early. Some of the first reactors were used for heat supply, e.g. Calder Hall (United Kingdom), Obninsk (Russian Federation), and Agesta (Sweden). Now, over 60 reactors are supplying heat for district heating, industrial processes and seawater desalination. But the nuclear option could be better deployed if it would provide a larger share of the heat market. In particular, seawater desalination using nuclear heat is of increasing interest to some IAEA Member States. In consideration of the growing experience being accumulated, the IAEA periodically reviews the progress and new developments in the field of nuclear heat applications. This publication summarizes the recent activities among Member States presented at a Technical Committee meeting in April 1999. The purpose of the meeting was to provide a forum for the exchange of up to date information on the prospect, design, safety and licensing aspects, and development of non-electrical applications of nuclear heat for industrial use. This mainly included seawater desalination and hydrogen production

  3. Melting of a phase change material in a horizontal annulus with discrete heat sources

    Directory of Open Access Journals (Sweden)

    Mirzaei Hooshyar

    2015-01-01

    Full Text Available Phase change materials have found many industrial applications such as cooling of electronic devices and thermal energy storage. This paper investigates numerically the melting process of a phase change material in a two-dimensional horizontal annulus with different arrangements of two discrete heat sources. The sources are positioned on the inner cylinder of the annulus and assumed as constant-temperature boundary conditions. The remaining portion of the inner cylinder wall as well as the outer cylinder wall is considered to be insulated. The emphasis is mainly on the effects of the arrangement of the heat source pair on the fluid flow and heat transfer features. The governing equations are solved on a non-uniform O type mesh using a pressure-based finite volume method with an enthalpy porosity technique to trace the solid and liquid interface. The results are obtained at Ra=104 and presented in terms of streamlines, isotherms, melting phase front, liquid fraction and dimensionless heat flux. It is observed that, depending on the arrangement of heat sources, the liquid fraction increases both linearly and non-linearly with time but will slow down at the end of the melting process. It can also be concluded that proper arrangement of discrete heat sources has the great potential in improving the energy storage system. For instance, the arrangement C3 where the heat sources are located on the bottom part of the inner cylinder wall can expedite the melting process as compared to the other arrangements.

  4. Progress and safety aspects in process heat utilization from nuclear systems

    International Nuclear Information System (INIS)

    Barnert, H.

    1995-01-01

    Report about the Status and the Progress in the Various Programs and Projects in the Federal Republic of Germany in Process Heat Utilization from the High Temperature Reactor and on Recent Changes of the Atomic Law in the Federal Republic of Germany with Big Influence on the Safety of Nuclear Energy Technology. (author)

  5. 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.

  6. Passive Decay Heat Removal Strategy of Integrated Passive Safety System (IPSS) for SBO-combined Accidents

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Ho; Chang, Soon Heung; Jeong, Yong Hoon [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2014-10-15

    The weak points of nuclear safety would be in outmoded nuclear power plants like the Fukushima reactors. One of the systems for the safety enhancement is integrated passive safety system (IPSS) proposed after the Fukushima accidents. It has the five functions for the prevention and mitigation of a severe accident. Passive decay heat removal (PDHR) strategy using IPSS is proposed for coping with SBO-combined accidents in this paper. The two systems for removing decay heat before core-melt were applied in the strategy. The accidents were simulated by MARS code. The reference reactor was OPR1000, specifically Ulchin-3 and 4. The accidents included loss-of-coolant accidents (LOCA) because the coolant losses could be occurred in the SBO condition. The examples were the stuck open of PSV, the abnormal open of SDV and the leakage of RCP seal water. Also, as LOCAs with the failure of active safety injection systems were considered, various LOCAs were simulated in SBO. Based on the thermal hydraulic analysis, the probabilistic safety analysis was carried out for the PDHR strategy to estimate the safety enhancement in terms of the variation of core damage frequency. AIMS-PSA developed by KAERI was used for calculating CDF of the plant. The IPSS was applied in the PDHR strategy which was developed in order to cope with the SBO-combined accidents. The estimation for initiating SGGI or PSIS was based on the pressure in RCS. The simulations for accidents showed that the decay heat could be removed for the safety duration time in SBO. The increase of safety duration time from the strategy provides the increase of time for the restoration of AC power.

  7. Testing of PCM Heat Storage Modules with Solar Collectors as Heat Source

    DEFF Research Database (Denmark)

    Englmair, Gerald; Dannemand, Mark; Johansen, Jakob Berg

    2016-01-01

    A latent heat storage based on the phase change material Sodium Acetate Trihydrate (SAT) has been tested as part of a demonstration system. The full heat storage consisted of 4 individual modules each containing about 200 kg of sodium acetate trihydrate with different additives. The aim...... was to actively utilize the ability of the material to supercool to obtain long storage periods. The modules were charged with solar heat supplied by 22.4 m2 evacuated tubular collectors. The investigation showed that it was possible to fully charge one module within a period of 270 minutes with clear skies...

  8. National Certification Standard for Ground Source Heat Pump Personnel

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, John [Geothermal Heat Pump Consortium, Washington, DC (United States)

    2013-07-31

    The National Certification Standard for the Geothermal Heat Pump Industry adds to the understanding of the barriers to rapid growth of the geothermal heat pump (GHP) industry by bringing together for the first time an analysis of the roles and responsibilities of each of the individual job tasks involved in the design and installation of GHP systems. The standard addresses applicable qualifications for all primary personnel involved in the design, installation, commissioning, operation and maintenance of GHP systems, including their knowledge, skills and abilities. The resulting standard serves as a foundation for subsequent development of curriculum, training and certification programs, which are not included in the scope of this project, but are briefly addressed in the standard to describe ways in which the standard developed in this project may form a foundation to support further progress in accomplishing those other efforts. Follow-on efforts may use the standard developed in this project to improve the technical effectiveness and economic feasibility of curriculum development and training programs for GHP industry personnel, by providing a more complete and objective assessment of the individual job tasks necessary for successful implementation of GHP systems. When incorporated into future certification programs for GHP personnel, the standard will facilitate increased consumer confidence in GHP technology, reduce the potential for improperly installed GHP systems, and assure GHP system quality and performance, all of which benefit the public through improved energy efficiency and mitigated environmental impacts of the heating and cooling of homes and businesses.

  9. Wastewater as a Heat Source for Individual Residence Heating: A Techno-economic Feasibility Study in the Brussels Capital Region

    Directory of Open Access Journals (Sweden)

    Jan Spriet

    2017-09-01

    Full Text Available A large part of the thermal energy in buildings is lost through the drain and ends up as warm wastewater in the sewer system. The installation of heat exchangers in the sewer system enables a rise of the source temperature of heat pumps, increasing their coefficient of performance. To investigate the potential of such a technique in the Brussels Capital Region, a test facility named MYRTES has been installed in the sewer network, the starting point of this facility being to have one heat recovery system per residence. To estimate the heat recovery rate, potentially available in the Brussels Capital Region, the data from this test facility have been used as inputs and validation for a predictive model, considering both the heat recovery and its financial and environmental implications. Simulations show a minimum heating power of the heat pump of 6.3 kW, at a hot water temperature of 45 °C. A maximum of 35% of the buildings in the Brussels Capital Region are eligible for the use of such a system. At current tariffs, the levelized cost of energy for these systems, is lower than for traditional air heat pumps, but is higher than for gas boiler systems. The total equivalent warming impact, however, is estimated to be around 49% lower than for gas boiler systems and around 13% lower than for air heat pumps. In conclusion, heating through these types of systems is more expensive than gas boiler systems, but with increased consumption the competitiveness of these systems improves.

  10. The numerical simulation of heat transfer during a hybrid laser-MIG welding using equivalent heat source approach

    Science.gov (United States)

    Bendaoud, Issam; Matteï, Simone; Cicala, Eugen; Tomashchuk, Iryna; Andrzejewski, Henri; Sallamand, Pierre; Mathieu, Alexandre; Bouchaud, Fréderic

    2014-03-01

    The present study is dedicated to the numerical simulation of an industrial case of hybrid laser-MIG welding of high thickness duplex steel UR2507Cu with Y-shaped chamfer geometry. It consists in simulation of heat transfer phenomena using heat equivalent source approach and implementing in finite element software COMSOL Multiphysics. A numerical exploratory designs method is used to identify the heat sources parameters in order to obtain a minimal required difference between the numerical results and the experiment which are the shape of the welded zone and the temperature evolution in different locations. The obtained results were found in good correspondence with experiment, both for melted zone shape and thermal history.

  11. Thermal non-equilibrium heat transfer in a porous cavity in the presence of bio-chemical heat source

    Directory of Open Access Journals (Sweden)

    Nazari Mohsen

    2015-01-01

    Full Text Available This paper is concerned with thermal non-equilibrium natural convection in a square cavity filled with a porous medium in the presence of a biomass which is transported in the cavity. The biomass can consume a secondary moving substrate. The physics of the presented problem is related to the analysis of heat and mass transfer in a composting process that controlled by internal heat generation. The intensity of the bio-heat source generated in the cavity is equal to the rate of consumption of the substrate by the biomass. It is assumed that the porous medium is homogeneous and isotropic. A two-field model that represents the fluid and solid phase temperature fields separately is used for energy equation. A simplified Monod model is introduced along with the governing equations to describe the consumption of the substrate by the biomass. In other word, the transient biochemical heat source which is dependent on a solute concentration is considered in the energy equations. Investigation of the biomass activity and bio-chemical heat generation in the case of thermal non-equilibrium assumption has not been considered in the literature and they are open research topics. The effects of thermal non-equilibrium model on heat transfer, flow pattern and biomass transfer are investigated. The effective parameters which have a direct impact on the generated bio-chemical heat source are also presented. The influences of the non-dimensional parameters such as fluid-to-solid conductivity ratio on the temperature distribution are presented.

  12. Using Ground Source Heat Pumps for Renewable Energy

    OpenAIRE

    Xhevat BERISHA

    2017-01-01

    This paper provides background information on the current energy supply, energy demand, and energy sources in Kosovo. Moreover, it presents the country‟s current level of applying alternative energy sources. Additionally, this paper focuses on geothermal energy as a renewable energy resource with the potential to contribute to a sustainable use of resources to meet renewable energy and energy efficiency requirements of the European Union (EU), “EU 20 20 by 2020” policy. Hence, a careful analy...

  13. Energy recovery during expansion of compressed gas using power plant low-quality heat sources

    Science.gov (United States)

    Ochs, Thomas L [Albany, OR; O'Connor, William K [Lebanon, OR

    2006-03-07

    A method of recovering energy from a cool compressed gas, compressed liquid, vapor, or supercritical fluid is disclosed which includes incrementally expanding the compressed gas, compressed liquid, vapor, or supercritical fluid through a plurality of expansion engines and heating the gas, vapor, compressed liquid, or supercritical fluid entering at least one of the expansion engines with a low quality heat source. Expansion engines such as turbines and multiple expansions with heating are disclosed.

  14. Performance of water source heat pump system using high-density polyethylene tube heat exchanger wound with square copper wire

    Directory of Open Access Journals (Sweden)

    Xin Wen Zhang

    2015-07-01

    Full Text Available Surface water source heat pump system is an energy-efficient heat pump system. Surface water heat exchanger is an important part of heat pump system that can affect the performance of the system. In order to enhance the performance of the system, the overall heat transfer coefficient (U value of the water exchanger using a 32A square copper coiled high-density polyethylene tube was researched. Comparative experiments were conducted between the performance of the coiled high-density polyethylene tube and the 32A smooth high-density polyethylene tube. At the same time, the coefficient of performance of the heat pump was investigated. According to the result, the U value of the coiled tube was 18% higher than that of the smooth tube in natural convection and 19% higher in forced convection. The coefficient of performance of the heat pump with the coiled tube is higher than that with the smooth tube. The economic evaluation of the coiled tube was also investigated.

  15. Thermal performance and pressure drop of spiral-tube ground heat exchangers for ground-source heat pump

    International Nuclear Information System (INIS)

    Jalaluddin; Miyara, Akio

    2015-01-01

    Thermal performance and pressure drop of the spiral-tube GHE were evaluated in this present work. A numerical simulation tool was used to carry out this research. The heat exchange rates per meter borehole depth of the spiral-tube GHE with various pitches and their pressure drops were compared with that of the U-tube GHE. Furthermore, a comparative analysis between a spiral pipe and straight pipe was performed. In comparison with the straight pipe, using the spiral pipe in the borehole increased the heat exchange rate to the ground per meter borehole depth. However, the pressure drop of water flow also increased due to increasing the length of pipe per meter borehole depth and its spiral geometry. The accuracy of the numerical model was verified for its pressure drop with some pressure drop correlations. The heat exchange rate and pressure drop of the GHEs are presented. As an example, the heat exchange rate per meter borehole depth of spiral pipe with 0.05 m pitch in the turbulent flow increased of 1.5 times. Its pressure drop also increased of 6 times. However, from the view point of energy efficiency, using the spiral pipe in the ground-source heat pump system gives a better performance than using the straight pipe. The heat exchange rate and pressure drop are important parameter in design of the ground-source heat pump (GSHP) system. - Highlights: • Thermal performance and pressure drop of spiral-tube GHE are presented. • Effects of spiral pitch on thermal performance and pressure drop are analyzed. • Using a spiral pipe increases heat exchange rate per meter borehole depth of GHE. • Pressure drop per meter borehole depth also increases in the spiral pipe.

  16. ENERGY STAR Certified Non-AHRI Central Air Conditioner Equipment and Air Source Heat Pump

    Data.gov (United States)

    U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 5.0 ENERGY STAR Program Requirements for Air Source Heat Pump and Central Air Conditioner...

  17. An amplitude and phase control system for the TFTR rf heating sources

    International Nuclear Information System (INIS)

    Cutsogeorge, G.

    1989-04-01

    Feedback loops that control the amplitude and phase of the rf heating sources on TFTR are described. The method for providing arc protection is also discussed. Block diagrams and Bode plots are included. 6 figs

  18. Milliwatt-generator heat source. Progress report, January-June 1983

    International Nuclear Information System (INIS)

    Mershad, E.A.

    1983-01-01

    Progress is reported in the following: heat source shipments, reimbursable orders, hardware shipments, raw material qualification/procurement, DOE audit and milliwatt generator process review, surveillance capsule evaluations, pressure burst testing, and hardware fabrication and quality

  19. Energy well. Ground-source heat in one-family houses; Energiakaivo. Maalaemmoen hyoedyntaeminen pientaloissa

    Energy Technology Data Exchange (ETDEWEB)

    Juvonen, J.; Lapinlampi, T.

    2013-08-15

    This guide deals with the legislation, planning, building, usage and maintenance of ground-source heat systems. The guide gives recommendations and instructions on national level on the permit practices and how to carry out the whole ground-source heat system project. The main focus of the guide is on energy wells for one-family houses. The principle is that an action permit is needed to build a ground-source heat system. On ground water areas a permit according to the water act may also be required. To avoid any problems, the placement of the system needs to be planned precisely. This guide gives a comprehension to the orderer on the issues that need to be considered before ordering, during construction, when the system is running and when giving up the use of the ground-source heat system. (orig.)

  20. Material impacts and heat flux characterization of an electrothermal plasma source with an applied magnetic field

    Science.gov (United States)

    Gebhart, T. E.; Martinez-Rodriguez, R. A.; Baylor, L. R.; Rapp, J.; Winfrey, A. L.

    2017-08-01

    To produce a realistic tokamak-like plasma environment in linear plasma device, a transient source is needed to deliver heat and particle fluxes similar to those seen in an edge localized mode (ELM). ELMs in future large tokamaks will deliver heat fluxes of ˜1 GW/m2 to the divertor plasma facing components at a few Hz. An electrothermal plasma source can deliver heat fluxes of this magnitude. These sources operate in an ablative arc regime which is driven by a DC capacitive discharge. An electrothermal source was configured with two pulse lengths and tested under a solenoidal magnetic field to determine the resulting impact on liner ablation, plasma parameters, and delivered heat flux. The arc travels through and ablates a boron nitride liner and strikes a tungsten plate. The tungsten target plate is analyzed for surface damage using a scanning electron microscope.

  1. On the addition of heat to solar pond from external sources

    NARCIS (Netherlands)

    Ganguly, S.; Jain, Ravi; Date, Abhijit; Akbarzadeh, Aliakbar

    2017-01-01

    This brief note addresses the method of adding heat to a solar pond from an external source which is used to enhance the performance of a solar pond. Heat energy collected by Evacuated Tube Solar Collectors (ETSC) is transferred by circulating fluid from the Lower Convective Zone (LCZ) of a solar

  2. Numerical analysis of the heat source characteristics of a two-electrode TIG arc

    International Nuclear Information System (INIS)

    Ogino, Y; Hirata, Y; Nomura, K

    2011-01-01

    Various kinds of multi-electrode welding processes are used to ensure high productivity in industrial fields such as shipbuilding, automotive manufacturing and pipe fabrication. However, it is difficult to obtain the optimum welding conditions for a specific product, because there are many operating parameters, and because welding phenomena are very complicated. In the present research, the heat source characteristics of a two-electrode TIG arc were numerically investigated using a 3D arc plasma model with a focus on the distance between the two electrodes. The arc plasma shape changed significantly, depending on the electrode spacing. The heat source characteristics, such as the heat input density and the arc pressure distribution, changed significantly when the electrode separation was varied. The maximum arc pressure of the two-electrode TIG arc was much lower than that of a single-electrode TIG. However, the total heat input of the two-electrode TIG arc was nearly constant and was independent of the electrode spacing. These heat source characteristics of the two-electrode TIG arc are useful for controlling the heat input distribution at a low arc pressure. Therefore, these results indicate the possibility of a heat source based on a two-electrode TIG arc that is capable of high heat input at low pressures.

  3. Estimation of heat transfer and heat source in a molten pool

    Energy Technology Data Exchange (ETDEWEB)

    Yun, J.I.; Suh, K.Y.; Kang, C.S. [Seoul National Univ., Dept. of Nuclear Engineering (Korea, Republic of)

    2001-07-01

    Heat transfer and fluid flow in a molten pool are influenced by internal volumetric heat generated from the radioactive decay of fission product species retained in the pool. The pool superheat is determined based on the overall energy balance that equates the heat production rate to the heat loss rate. Decay heat of fission products in the pool was estimated by product of the mass concentration and energy conversion factor of each fission product. For the calculation of heat generation rate in the pool, twenty-nine (29) elements were chosen and classified by their chemical properties. The mass concentration of a fission product is obtained from released fraction and the tabular output of the ORIGEN 2 code. The initial core and pool inventories at each time can also be estimated using ORIGEN 2. The released fraction of each fission product is calculated based on the bubble dynamics and mass transport. Numerical analysis was performed for the TMI-2 accident. The pool is assumed to be a partially filled hemispherical geometry, 1.45 m in radius and 32,700 kg in mass. The change of pool geometry during the numerical calculation was neglected. The peak temperature sizably decreased by about 60 K as the fission products were released from the pool. (author)

  4. Estimation of heat transfer and heat source in a molten pool

    International Nuclear Information System (INIS)

    Yun, J.I.; Suh, K.Y.; Kang, C.S.

    2001-01-01

    Heat transfer and fluid flow in a molten pool are influenced by internal volumetric heat generated from the radioactive decay of fission product species retained in the pool. The pool superheat is determined based on the overall energy balance that equates the heat production rate to the heat loss rate. Decay heat of fission products in the pool was estimated by product of the mass concentration and energy conversion factor of each fission product. For the calculation of heat generation rate in the pool, twenty-nine (29) elements were chosen and classified by their chemical properties. The mass concentration of a fission product is obtained from released fraction and the tabular output of the ORIGEN 2 code. The initial core and pool inventories at each time can also be estimated using ORIGEN 2. The released fraction of each fission product is calculated based on the bubble dynamics and mass transport. Numerical analysis was performed for the TMI-2 accident. The pool is assumed to be a partially filled hemispherical geometry, 1.45 m in radius and 32,700 kg in mass. The change of pool geometry during the numerical calculation was neglected. The peak temperature sizably decreased by about 60 K as the fission products were released from the pool. (author)

  5. Entropy Generation Analysis of Natural Convection in Square Enclosures with Two Isoflux Heat Sources

    Directory of Open Access Journals (Sweden)

    S. Z. Nejad

    2017-04-01

    Full Text Available This study investigates entropy generation resulting from natural convective heat transfer in square enclosures with local heating of the bottom and symmetrical cooling of the sidewalls. This analysis tends to optimize heat transfer of two pieces of semiconductor in a square electronic package. In this simulation, heaters are modeled as isoflux heat sources and sidewalls of the enclosure are isothermal heat sinks. The top wall and the non-heated portions of the bottom wall are adiabatic. Flow and temperature fields are obtained by numerical simulation of conservation equations of mass, momentum and energy in laminar, steady and two dimensional flows. With constant heat energy into the cavity, effect of Rayleigh number, heater length, heater strength ratios and heater position is evaluated on flow and temperature fields and local entropy generation. The results show that a minimum entropy generation rate is obtained under the same condition in which a minimum peak heater temperature is obtained.

  6. Heat source component development program. Report for period March 1978--June 1978

    International Nuclear Information System (INIS)

    1978-07-01

    The General Purpose Heat Source (GPHS) is a radioisotope heat source being developed by LASL. The first intended application for the GPHS is the Solar Polar mission scheduled for 1983. Battelle's support of LASL during the current reporting period is reported. The specific efforts include: (1) analysis of trial designs with emphasis on comparison of performances of trial designs 1 and 2 and their modifications; and (2) helium vent development with emphasis on fabrication and qualification testing of platinum and iridium nonselective vents

  7. Flow Conditions in a Mechanically Ventilated Room with a Convective Heat Source

    DEFF Research Database (Denmark)

    Heiselberg, Per; Nielsen, Peter V.

    The ventilation of a test room (LxWxH = 5.4x3.6x2.4 m) with a wall mounted heat source is investigated for two different air terminal devices.......The ventilation of a test room (LxWxH = 5.4x3.6x2.4 m) with a wall mounted heat source is investigated for two different air terminal devices....

  8. 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.

  9. Infection as a Background to Safety: Source Material for Teaching.

    Science.gov (United States)

    Wyatt, H. V.

    1986-01-01

    Offers selections from papers which illustrate accidents, epidemics, and bad practices which could be used as background material for lessons on laboratory safety. Advocates the need for instruction on pathogenicity and infectivity. (ML)

  10. Radiation sources and materials safety and security in Georgia

    International Nuclear Information System (INIS)

    Mandjgaladze, G.; Tsitskishvili, M.; Abramidze, Sh.; Katamadze, N.

    1998-01-01

    This paper explains the problems of safety and security in Georgia, the most important incidents and accidents, their consequences (including severe injuries and deaths) and governmental actions for prevention and mitigation. (author)

  11. A new method to estimate heat source parameters in gas metal arc welding simulation process

    International Nuclear Information System (INIS)

    Jia, Xiaolei; Xu, Jie; Liu, Zhaoheng; Huang, Shaojie; Fan, Yu; Sun, Zhi

    2014-01-01

    Highlights: •A new method for accurate simulation of heat source parameters was presented. •The partial least-squares regression analysis was recommended in the method. •The welding experiment results verified accuracy of the proposed method. -- Abstract: Heat source parameters were usually recommended by experience in welding simulation process, which induced error in simulation results (e.g. temperature distribution and residual stress). In this paper, a new method was developed to accurately estimate heat source parameters in welding simulation. In order to reduce the simulation complexity, a sensitivity analysis of heat source parameters was carried out. The relationships between heat source parameters and welding pool characteristics (fusion width (W), penetration depth (D) and peak temperature (T p )) were obtained with both the multiple regression analysis (MRA) and the partial least-squares regression analysis (PLSRA). Different regression models were employed in each regression method. Comparisons of both methods were performed. A welding experiment was carried out to verify the method. The results showed that both the MRA and the PLSRA were feasible and accurate for prediction of heat source parameters in welding simulation. However, the PLSRA was recommended for its advantages of requiring less simulation data

  12. Magnetic pumping as a source of particle heating

    Science.gov (United States)

    Lichko, Emily; Egedal, Jan; Daughton, William; Kasper, Justin

    2017-10-01

    Magnetic pumping is a means of heating plasmas for both fusion and astrophysical applications. In this study a magnetic pumping model is developed as a possible explanation for the heating and the generation of power-law distribution functions observed in the solar wind plasma. In most previous studies turbulent energy is only dissipated at microscopic kinetic scales. In contrast, magnetic pumping energizes the particles through the largest scale turbulent fluctuations, thus bypassing the energy cascade. Kinetic simulations are applied to verify these analytic predictions. Previous results for the one-dimensional model, as well as initial results for a two-dimensional model which includes the effects of trapped and passing particles are presented. Preliminary results of the presence of this mechanism in the bow shock region, using spacecraft data from the Magnetospheric Multiscale mission, are presented as well. This research was conducted with support from National Defense Science and Engineering Graduate (NDSEG) Fellowship, 32 CFR 168, as well as from NSF Award 1404166 and NASA award NNX15AJ73G.

  13. Experimental performance analysis of a direct-expansion ground source heat pump in Xiangtan, China

    International Nuclear Information System (INIS)

    Yang, Wei

    2013-01-01

    The DX GSHP (direct-expansion ground source heat pump), which uses a buried copper piping network through which refrigerant is circulated, is one type of GSHP (ground source heat pump). This study investigates the performance characteristics of a vertical U-bend direct-expansion ground source (geothermal) heat pump system (DX GSHPS) for both heating and cooling. Compared with the conventional GCHP (ground coupled heat pump) system, the DX GSHP system is more efficient, with lower thermal resistance in the GHE (ground heat exchanger) and a lower (higher) condensing (evaporating) temperature in the cooling (heating) mode. In addition, the system performance of the whole DX GSHP system is also higher than that of the conventional GCHP system. A DX GSHP system in Xiangtan, China with a U-bend ground heat exchanger 42 m deep with a nominal outside diameter of 12.7 mm buried in a water well was tested and analysed. The results showed that the performance of this system is very high. The maximum (average) COPs of the system were found to be 6.08 (4.73) and 6.32 (5.03) in the heating and cooling modes, respectively. - Highlights: • The reasons for the higher performance of the DX GSHP (direct-expansion ground source heat pump) are analysed theoretically compared with the conventional GCHP (ground coupled heat pump). • The experimental performance of a DX GSHP system is investigated, which makes a valuable contribution to the literature. • The study is helpful in demonstrating the energy efficiency of the DX GSHP system

  14. Design and qualification testing of a strontium-90 fluoride heat source

    International Nuclear Information System (INIS)

    Fullam, H.T.

    1981-12-01

    The Strontium Heat Source Development Program began at the Pacific Northwest Laboratory (PNL) in 1972 and is scheduled to be completed by the end of FY-1981. The program is currently funded by the US Department of Energy (DOE) By-Product Utilization Program. The primary objective of the program has been to develop the data and technology required to permit the licensing of power systems for terrestrial applications that utilize 90 SrF 2 -fueled radioisotope heat sources. A secondary objective of the program has been to design and qualification-test a general purpose 90 SrF 2 -fueled heat source. The effort expended in the design and testing of the heat source is described. Detailed information is included on: heat source design, licensing requirements, and qualification test requirements; the qualification test procedures; and the fabrication and testing of capsules of various materials. The results obtained in the qualification tests show that the outer capsule design proposed for the 90 SrF 2 heat source is capable of meeting current licensing requirements when Hastelloy S is used as the outer capsule material. The data also indicate that an outer capsule of Hastelloy C-4 would probably also meet licensing requirements, although Hastelloy S is the preferred material. Therefore, based on the results of this study, the general purpose 90 SrF 2 heat source will consist of a standard WESF Hastelloy C-276 inner capsule filled with 90 SrF 2 and a Hastelloy S outer capsule having a 2.375-in. inner diameter and 0.500-in. wall thickness. The end closures for this study, the general purpose 90 SrF 2 heat a Hastelloy S outer capsule having a 2.375-in. inner diameter and 0.500-in. wall thickness. The end closures for the outer capsule will utilize an interlocking joint design requiring a 0.1-in. penetration closure weld

  15. Performance Analysis of Slinky Horizontal Ground Heat Exchangers for a Ground Source Heat Pump System

    Directory of Open Access Journals (Sweden)

    Md. Hasan Ali

    2017-10-01

    Full Text Available This paper highlights the thermal performance of reclined (parallel to ground surface and standing (perpendicular to ground surface slinky horizontal ground heat exchangers (HGHEs with different water mass flow rates in the heating mode of continuous and intermittent operations. A copper tube with an outer surface protected with low-density polyethylene was selected as the tube material of the ground heat exchanger. Effects on ground temperature around the reclined slinky HGHE due to heat extraction and the effect of variation of ground temperatures on reclined HGHE performance are discussed. A higher heat exchange rate was experienced in standing HGHE than in reclined HGHE. The standing HGHE was affected by deeper ground temperature and also a greater amount of backfilled sand in standing HGHE (4.20 m3 than reclined HGHE (1.58 m3, which has higher thermal conductivity than site soil. For mass flow rate of 1 L/min with inlet water temperature 7 °C, the 4-day average heat extraction rates increased 45.3% and 127.3%, respectively, when the initial average ground temperatures at 1.5 m depth around reclined HGHE increased from 10.4 °C to 11.7 °C and 10.4 °C to 13.7 °C. In the case of intermittent operation, which boosted the thermal performance, a short time interval of intermittent operation is better than a long time interval of intermittent operation. Furthermore, from the viewpoint of power consumption by the circulating pump, the intermittent operation is more efficient than continuous operation.

  16. Milk of the cow as a source [for heat pumps]; Koe als bronsysteem

    Energy Technology Data Exchange (ETDEWEB)

    Roestenberg, B.

    2012-09-15

    A livestock farm in Joure, the Netherlands, has designed a heat pump system that uses milk as a source. Up to now, three livestock farms in the Netherlands have been equipped with the so-called ECO2000 system that extracts heat from milk, using a heat pump to use this heat elsewhere in the business [Dutch] Een veeteeltbedrijf in Joure, Nederland, heeft een warmtepompsysteem ontworpen dat melk gebruikt als bron. Inmiddels zijn drie melkveehouderijen in Nederland voorzien van het zogenaamde ECO2000 systeem waarbij warmte wordt onttrokken uit melk om via een warmtepomp elders in het bedrijf te worden hergebruikt.

  17. Experimental investigation on water quality standard of Yangtze River water source heat pump.

    Science.gov (United States)

    Qin, Zenghu; Tong, Mingwei; Kun, Lin

    2012-01-01

    Due to the surface water in the upper reaches of Yangtze River in China containing large amounts of silt and algae, high content of microorganisms and suspended solids, the water in Yangtze River cannot be used for cooling a heat pump directly. In this paper, the possibility of using Yangtze River, which goes through Chongqing, a city in southwest China, as a heat source-sink was investigated. Water temperature and quality of the Yangtze River in the Chongqing area were analyzed and the performance of water source heat pump units in different sediment concentrations, turbidity and algae material conditions were tested experimentally, and the water quality standards, in particular surface water conditions, in the Yangtze River region that adapt to energy-efficient heat pumps were also proposed. The experimental results show that the coefficient of performance heat pump falls by 3.73% to the greatest extent, and the fouling resistance of cooling water in the heat exchanger increases up to 25.6% in different water conditions. When the sediment concentration and the turbidity in the river water are no more than 100 g/m3 and 50 NTU respectively, the performance of the heat pump is better, which can be used as a suitable river water quality standard for river water source heat pumps.

  18. Internal heat gain from different light sources in the building lighting systems

    Directory of Open Access Journals (Sweden)

    Suszanowicz Dariusz

    2017-01-01

    Full Text Available EU directives and the Construction Law have for some time required investors to report the energy consumption of buildings, and this has indeed caused low energy consumption buildings to proliferate. Of particular interest, internal heat gains from installed lighting affect the final energy consumption for heating of both public and residential buildings. This article presents the results of analyses of the electricity consumption and the luminous flux and the heat flux emitted by different types of light sources used in buildings. Incandescent light, halogen, compact fluorescent bulbs, and LED bulbs from various manufacturers were individually placed in a closed and isolated chamber, and the parameters for their functioning under identical conditions were recorded. The heat flux emitted by 1 W nominal power of each light source was determined. Based on the study results, the empirical coefficients of heat emission and energy efficiency ratios for different types of lighting sources (dependent lamp power and the light output were designated. In the heat balance of the building, the designated rates allow for precise determination of the internal heat gains coming from lighting systems using various light sources and also enable optimization of lighting systems of buildings that are used in different ways.

  19. Internal heat gain from different light sources in the building lighting systems

    Science.gov (United States)

    Suszanowicz, Dariusz

    2017-10-01

    EU directives and the Construction Law have for some time required investors to report the energy consumption of buildings, and this has indeed caused low energy consumption buildings to proliferate. Of particular interest, internal heat gains from installed lighting affect the final energy consumption for heating of both public and residential buildings. This article presents the results of analyses of the electricity consumption and the luminous flux and the heat flux emitted by different types of light sources used in buildings. Incandescent light, halogen, compact fluorescent bulbs, and LED bulbs from various manufacturers were individually placed in a closed and isolated chamber, and the parameters for their functioning under identical conditions were recorded. The heat flux emitted by 1 W nominal power of each light source was determined. Based on the study results, the empirical coefficients of heat emission and energy efficiency ratios for different types of lighting sources (dependent lamp power and the light output) were designated. In the heat balance of the building, the designated rates allow for precise determination of the internal heat gains coming from lighting systems using various light sources and also enable optimization of lighting systems of buildings that are used in different ways.

  20. A flexible and low cost experimental stand for air source heat pump for Smart Buildings

    DEFF Research Database (Denmark)

    Crăciun, Vasile S.; Bojesen, Carsten; Blarke, Morten

    2012-01-01

    Energy systems are faced with the challenges of reducing dependency on fossil fuels, while handling increasing penetration levels of intermittent renewables such as wind and solar power. At the same time, the efficient consumption of energy is vital for avoiding the impacts from increasing fuel...... prices. A significant part of this challenge may be dealt with in the way space heating, space cooling, and domestic hot water production which is provided to residential and commercial buildings. Air source heat pumps (ASHP) are widely used conversion technologies for providing building thermal energy...... services; cooling, heating, and water heating. ASHP does not have a constant temperature for the primary source like: soil, ground water, or surface water heat pumps. In result, laboratory experiments and tests are faced by the problem of having to handle a wide range of conditions under which...

  1. Large-eddy simulation of convective boundary layer generated by highly heated source with open source code, OpenFOAM

    International Nuclear Information System (INIS)

    Hattori, Yasuo; Suto, Hitoshi; Eguchi, Yuzuru; Sano, Tadashi; Shirai, Koji; Ishihara, Shuji

    2011-01-01

    Spatial- and temporal-characteristics of turbulence structures in the close vicinity of a heat source, which is a horizontal upward-facing round plate heated at high temperature, are examined by using well resolved large-eddy simulations. The verification is carried out through the comparison with experiments: the predicted statistics, including the PDF distribution of temperature fluctuations, agree well with measurements, indicating that the present simulations have a capability to appropriately reproduce turbulence structures near the heat source. The reproduced three-dimensional thermal- and fluid-fields in the close vicinity of the heat source reveals developing processes of coherence structures along the surface: the stationary- and streaky-flow patterns appear near the edge, and such patterns randomly shift to cell-like patterns with incursion into the center region, resulting in thermal-plume meandering. Both the patterns have very thin structures, but the depth of streaky structure is considerably small compared with that of cell-like patterns; this discrepancy causes the layered structures. The structure is the source of peculiar turbulence characteristics, the prediction of which is quite difficult with RANS-type turbulence models. The understanding such structures obtained in present study must be helpful to improve the turbulence model used in nuclear engineering. (author)

  2. Multi-purpose nuclear heat source for advanced gas-cooled reactor plants

    International Nuclear Information System (INIS)

    McDonald, C.F.

    1993-01-01

    Nuclear power has the potential to be the ultimate green technology in that it could eliminate the need for burning fossil fuels with their polluting combustion products and greenhouse gases. This view is shared by many technologists, but it may be a generation before the public becomes convinced, and that will involve overcoming many safety, institutional, financial, and technical impediments. This paper addresses only the latter topic; a major theme being that for nuclear power to truly be a green technology and significantly benefit society, it must meet the needs of the full energy spectrum. Specifically, it must satisfy energy needs beyond just the electricity generating sector by today's nuclear plants. By virtue of its high temperature capability, the Modular High Temperature Gas-Cooled Reactor (MHTGR) is the only type of reactor that has the potential to meet the wide range of energy needs that will emerge in the future. This paper discusses the nuclear heat source that gives the MHTGR multi-purpose capability, which is recognized today, but will not be implemented until early in the next century

  3. Preliminary design study of an alternate heat source assembly for a Brayton isotope power system

    Science.gov (United States)

    Strumpf, H. J.

    1978-01-01

    Results are presented for a study of the preliminary design of an alternate heat source assembly (HSA) intended for use in the Brayton isotope power system (BIPS). The BIPS converts thermal energy emitted by a radioactive heat source into electrical energy by means of a closed Brayton cycle. A heat source heat exchanger configuration was selected and optimized. The design consists of a 10 turn helically wound Hastelloy X tube. Thermal analyses were performed for various operating conditions to ensure that post impact containment shell (PICS) temperatures remain within specified limits. These limits are essentially satisfied for all modes of operation except for the emergency cooling system for which the PICS temperatures are too high. Neon was found to be the best choice for a fill gas for auxiliary cooling system operation. Low cycle fatigue life, natural frequency, and dynamic loading requirements can be met with minor modifications to the existing HSA.

  4. Performance analysis of air source heat pump system for office building

    Energy Technology Data Exchange (ETDEWEB)

    Han, Dong Won; KIm, Yong Chan [Korea University, Seoul (Korea, Republic of); Chang, Young Soo [School of Mechanical System Engineering, Kookmin University, Seoul (Korea, Republic of)

    2016-11-15

    In this study, the performance of an air source heat pump system installed in a commercial building is analyzed using the developed heat pump performance model and building load simulation data of several regions in Korea. The performance test of an air source heat pump system with a variable speed compressor is tested to develop model that considers changes in the performance characteristics of the heat pump system under various operating conditions. The heat pump system is installed in an environmental chamber, and the experimental equipment is set up according to the manufacturer' specifications as well as the AHRI 1230 test specifications. The performance test conditions of the heat pump system are selected using a central composite design method, in which 29 points for each cooling and heating mode are selected. The developed performance model based on experimental data predicts experimental values with an error of ±5 %. Building cooling and heating loads in three regions in Korea are analyzed using TRNSYS software, which includes standard building and weather data from Seoul, Daejeon and Busan in Korea. The effects of outdoor air temperature and part load ratio on the performance and regional monthly average power consumption of the heat pump system are analyzed.

  5. Research on Heat Dissipation of Electric Vehicle Based on Safety Architecture Optimization

    Science.gov (United States)

    Zhou, Chao; Guo, Yajuan; Huang, Wei; Jiang, Haitao; Wu, Liwei

    2017-10-01

    In order to solve the problem of excessive temperature in the discharge process of lithium-ion battery and the temperature difference between batteries, a heat dissipation of electric vehicle based on safety architecture optimization is designed. The simulation is used to optimize the temperature field of the heat dissipation of the battery. A reasonable heat dissipation control scheme is formulated to achieve heat dissipation requirements. The results show that the ideal working temperature range of the lithium ion battery is 20?∼45?, and the temperature difference between the batteries should be controlled within 5?. A cooling fan is arranged at the original air outlet of the battery model, and the two cooling fans work in turn to realize the reciprocating flow. The temperature difference is controlled within 5? to ensure the good temperature uniformity between the batteries of the electric vehicle. Based on the above finding, it is concluded that the heat dissipation design for electric vehicle batteries is safe and effective, which is the most effective methods to ensure battery life and vehicle safety.

  6. Thermal energy storage system using phase change materials: Constant heat source

    Directory of Open Access Journals (Sweden)

    Reddy Meenakshi R.

    2012-01-01

    Full Text Available The usage of phase change materials (PCM to store the heat in the form of latent heat is increased, because large quantity of thermal energy is stored in smaller volumes. In the present experimental investigation paraffin and stearic acid are employed as PCMs in thermal energy storage (TES system to store the heat as sensible and latent heat also. A constant heat source is used to supply heat transfer fluid (HTF at constant temperature to the TES system. In the TES system PCMs are stored in the form of spherical capsules of 38 mm diameter made of high density poly ethylene (HDPE. The results of the investigation are related to the charging time and recovery of stored energy from the TES system.

  7. Dynamics of charged bulk viscous collapsing cylindrical source with heat flux

    Energy Technology Data Exchange (ETDEWEB)

    Shah, S.M.; Abbas, G. [The Islamia University of Bahawalpur, Department of Mathematics, Bahawalpur (Pakistan)

    2017-04-15

    In this paper, we have explored the effects of dissipation on the dynamics of charged bulk viscous collapsing cylindrical source which allows the out-flow of heat flux in the form of radiations. The Misner-Sharp formalism has been implemented to drive the dynamical equation in terms of proper time and radial derivatives. We have investigated the effects of charge and bulk viscosity on the dynamics of collapsing cylinder. To determine the effects of radial heat flux, we have formulated the heat transport equations in the context of Mueller-Israel-Stewart theory by assuming that thermodynamics viscous/heat coupling coefficients can be neglected within some approximations. In our discussion, we have introduced the viscosity by the standard (non-causal) thermodynamics approach. The dynamical equations have been coupled with the heat transport equation; the consequences of the resulting coupled heat equation have been analyzed in detail. (orig.)

  8. Nonlinear radiated MHD flow of nanoliquids due to a rotating disk with irregular heat source and heat flux condition

    Science.gov (United States)

    Mahanthesh, B.; Gireesha, B. J.; Shehzad, S. A.; Rauf, A.; Kumar, P. B. Sampath

    2018-05-01

    This research is made to visualize the nonlinear radiated flow of hydromagnetic nano-fluid induced due to rotation of the disk. The considered nano-fluid is a mixture of water and Ti6Al4V or AA7072 nano-particles. The various shapes of nanoparticles like lamina, column, sphere, tetrahedron and hexahedron are chosen in the analysis. The irregular heat source and nonlinear radiative terms are accounted in the law of energy. We used the heat flux condition instead of constant surface temperature condition. Heat flux condition is more relativistic and according to physical nature of the problem. The problem is made dimensionless with the help of suitable similarity constraints. The Runge-Kutta-Fehlberg scheme is adopted to find the numerical solutions of governing nonlinear ordinary differential systems. The solutions are plotted by considering the various values of emerging physical constraints. The effects of various shapes of nanoparticles are drawn and discussed.

  9. Solution to Two-Dimensional Steady Inverse Heat Transfer Problems with Interior Heat Source Based on the Conjugate Gradient Method

    Directory of Open Access Journals (Sweden)

    Shoubin Wang

    2017-01-01

    Full Text Available The compound variable inverse problem which comprises boundary temperature distribution and surface convective heat conduction coefficient of two-dimensional steady heat transfer system with inner heat source is studied in this paper applying the conjugate gradient method. The introduction of complex variable to solve the gradient matrix of the objective function obtains more precise inversion results. This paper applies boundary element method to solve the temperature calculation of discrete points in forward problems. The factors of measuring error and the number of measuring points zero error which impact the measurement result are discussed and compared with L-MM method in inverse problems. Instance calculation and analysis prove that the method applied in this paper still has good effectiveness and accuracy even if measurement error exists and the boundary measurement points’ number is reduced. The comparison indicates that the influence of error on the inversion solution can be minimized effectively using this method.

  10. ITER Safety Task NID-5A, Subtask 1-1: Source terms and energies - initial tritium source terms. Final report

    International Nuclear Information System (INIS)

    Fong, C.; Kalyanam, K.M.; Tanaka, M.R.; Sood, S.; Natalizio, A.; Delisle, M.

    1995-02-01

    The overall objective of the Early Safety and Environmental Characterization Study (ESECS) is to assess the environmental impact of tritium using appropriate assumptions on a hypothetical site for ITER, having the r eference s ite characteristics as proposed by the JCT. The objective of this work under the above subtask 1-1, NID-5a, is to determine environmental source terms (i.e., process source term x containment release fraction) for the fuel cycle and cooling systems. The work is based on inventories and process source terms (i.e., inventory x mobilization fraction), provided by others (under Task NID 3b). The results of this work form the basis for the determination, by others, of the off-site dose (i.e., environmental source term x dose/release ratio). For the determination of the environmental source terms, the TMAP4 code has been utilized (ref 1). This code is approved by ITER for safety assessment. 6 refs

  11. An inductively heated hot cavity catcher laser ion source

    CERN Document Server

    Reponen, M; Pohjalainen, I; Rothe, S; Savonen, M; Sonnenschein, V; Voss, A

    2015-01-01

    An inductively heated hot cavity catcher has been constructed for the production of low-energy ion beams of exotic, neutron-deficient Agisotopes. A proof-of-principle experiment has been realized by implanting primary 107Ag21+ ions from a heavy-ion cyclotron into a graphite catcher. A variable-thickness nickel foil was used to degrade the energy of the primary beam in order to mimic the implantation depth expected from the heavy-ion fusion-evaporation recoils of N = Z94Ag. Following implantation, the silver atoms diffused out of the graphite and effused into the catcher cavity and transfer tube, where they were resonantly laser ionized using a three-step excitation and ionization scheme. Following mass separation, the ions were identified by scanning the frequency of the first resonant excitation step while recording the ion count rate. Ion release time profiles were measured for different implantation depths and cavity temperatures with the mean delay time varying from 10 to 600 ms. In addition, the diffusio...

  12. A review of international sources for road safety measures assessment.

    NARCIS (Netherlands)

    Yannis, G. Weijermars, W. & Kauppila, J.

    2012-01-01

    The efficiency assessment of road safety measures is considered to be an extremely useful tool in decision making; in particular, cost-benefit and cost-effectiveness analyses are carried out in several countries, in a more or less systematic way. The objective of this paper is to present findings

  13. Residential home heating: The potential for air source heat pump technologies as an alternative to solid and liquid fuels

    International Nuclear Information System (INIS)

    Kelly, J. Andrew; Fu, Miao; Clinch, J. Peter

    2016-01-01

    International commitments on greenhouse gases, renewables and air quality warrant consideration of alternative residential heating technologies. The residential sector in Ireland accounts for approximately 25% of primary energy demand with roughly half of primary home heating fuelled by oil and 11% by solid fuels. Displacing oil and solid fuel usage with air source heat pump (ASHP) technology could offer household cost savings, reductions in emissions, and reduced health impacts. An economic analysis estimates that 60% of homes using oil, have the potential to deliver savings in the region of €600 per annum when considering both running and annualised capital costs. Scenario analysis estimates that a grant of €2400 could increase the potential market uptake of oil users by up to 17% points, whilst a higher oil price, similar to 2013, could further increase uptake from heating oil users by 24% points. Under a combined oil-price and grant scenario, CO_2 emissions reduce by over 4 million tonnes per annum and residential PM_2_._5 and NO_X emissions from oil and peat reduce close to zero. Corresponding health and environmental benefits are estimated in the region of €100m per annum. Sensitivity analyses are presented assessing the impact of alternate discount rates and technology performance. This research confirms the potential for ASHP technology and identifies and informs policy design considerations with regard to oil price trends, access to capital, targeting of grants, and addressing transactions costs. - Highlights: • Air Source Heat Pumps can offer substantial savings over oil fired central heating. • Significant residential air and climate emission reductions are possible. • Associated health and environmental benefits are estimated up to €100m per annum. • Results can inform policy interventions in the residential market to support change.

  14. Fuel-efficiency of hydrogen and heat storage technologies for integration of fluctuating renewable energy sources

    DEFF Research Database (Denmark)

    Mathiesen, Brian Vad; Lund, Henrik

    2005-01-01

    This paper presents the methodology and results of analysing the use of different energy storage technologies in the task of integration of fluctuating renewable energy sources (RES) into the electricity supply. The analysis is done on the complete electricity system including renewable energy...... sources as well as power plants and CHP (Combined heat and power production). Emphasis is put on the need for ancillary services. Devices to store electricity as well as devices to store heat can be used to help the integration of fluctuating sources. Electricity storage technologies can be used...... to relocate electricity production directly from the sources, while heat storage devices can be used to relocate the electricity production from CHP plants and hereby improve the ability to integrate RES. The analyses are done by advanced computer modelling and the results are given as diagrams showing...

  15. Recuperator with microjet technology as a proposal for heat recovery from low-temperature sources

    Directory of Open Access Journals (Sweden)

    Wajs Jan

    2015-12-01

    Full Text Available A tendency to increase the importance of so-called dispersed generation, based on the local energy sources and the working systems utilizing both the fossil fuels and the renewable energy resources is observed nowadays. Generation of electricity on industrial or domestic scale together with production of heat can be obtained for example through employment of the ORC systems. It is mentioned in the EU directive 2012/27/EU for cogenerative production of heat and electricity. For such systems the crucial points are connected with the heat exchangers, which should be small in size but be able to transfer high heat fluxes. In presented paper the prototype microjet heat exchanger dedicated for heat recovery systems is introduced. Its novel construction is described together with the systematical experimental analysis of heat transfer and flow characteristics. Reported results showed high values of the overall heat transfer coefficient and slight increase in the pressure drop. The results of microjet heat exchanger were compared with the results of commercially available compact plate heat exchanger.

  16. Recuperator with microjet technology as a proposal for heat recovery from low-temperature sources

    Science.gov (United States)

    Wajs, Jan; Mikielewicz, Dariusz; Fornalik-Wajs, Elżbieta; Bajor, Michał

    2015-12-01

    A tendency to increase the importance of so-called dispersed generation, based on the local energy sources and the working systems utilizing both the fossil fuels and the renewable energy resources is observed nowadays. Generation of electricity on industrial or domestic scale together with production of heat can be obtained for example through employment of the ORC systems. It is mentioned in the EU directive 2012/27/EU for cogenerative production of heat and electricity. For such systems the crucial points are connected with the heat exchangers, which should be small in size but be able to transfer high heat fluxes. In presented paper the prototype microjet heat exchanger dedicated for heat recovery systems is introduced. Its novel construction is described together with the systematical experimental analysis of heat transfer and flow characteristics. Reported results showed high values of the overall heat transfer coefficient and slight increase in the pressure drop. The results of microjet heat exchanger were compared with the results of commercially available compact plate heat exchanger.

  17. New developments in two-phase flow heat transfer with emphasis on nuclear safety research

    International Nuclear Information System (INIS)

    Mayinger, F.

    1987-01-01

    The literature on two-phase flow - with and without heat transfer - shows an explosive-like growth of published papers within the last ten years. Many of these papers were published as a result of nuclear safety research. It is impossible to deal with all new developments reported in this extensive literature. So one has to ask: Are there trends of special interest, where this report could be concentrated on? Looking over the situation, there seem to be three very promising fields of research having high actuality, especially for nuclear safety, namely: fluiddynamic and thermodynamic nonequilibrium in steady state, transient conditions, and scaling. The discussion on new developments in two-phase flow heat transfer, therefore, is limited on these subjects

  18. Analysis of the Potential of Low-Temperature Heat Pump Energy Sources

    Directory of Open Access Journals (Sweden)

    Pavel Neuberger

    2017-11-01

    Full Text Available The paper deals with an analysis of temperatures of ground masses in the proximities of linear and slinky-type HGHE (horizontal ground heat exchanger. It evaluates and compares the potentials of HGHEs and ambient air. The reason and aim of the verification was to gain knowledge of the temperature course of the monitored low-temperature heat pump energy sources during heating periods and periods of stagnation and to analyse the knowledge in terms of the potential to use those sources for heat pumps. The study was conducted in the years 2012–2015 during three heating periods and three periods of HGHEs stagnation. The results revealed that linear HGHE had the highest temperature potential of the observed low-temperature heat pump energy sources. The average daily temperatures of the ground mass surrounding the linear HGHE were the highest ranging from 7.08 °C to 9.20 °C during the heating periods, and having the lowest temperature variation range of 12.62–15.14 K, the relative frequency of the average daily temperatures of the ground mass being the highest at 22.64% in the temperature range containing the mode of all monitored temperatures in a recorded interval of [4.10, 6.00] °C. Ambient air had lower temperature potential than the monitored HGHEs.

  19. Preliminary safety analysis of a PBMR supplying process heat to a co-located ethylene production plant

    International Nuclear Information System (INIS)

    Scarlat, Raluca O.; Cisneros, Anselmo T.; Koutchesfahani, Tawni; Hong, Rada; Peterson, Per F.

    2012-01-01

    This paper considers the safety analysis and licensing approach for co-locating a pebble bed modular reactor (PBMR) to provide process heat to an ethylene production unit. The PBMR is an advanced nuclear reactor design that provides 400 MW of thermal energy. Ethylene production is an energy intensive process that utilizes large gas furnaces to provide the heat for the process. Coupling a PBMR with an ethylene production plant would open a new market for nuclear power, and would provide the chemical industry with a cleaner power source, helping to achieve the Clean Air Act standards, and eliminating the 0.5 ton of CO 2 emissions per ton of produced ethylene. Our analysis uses the Chevron Phillips chemical plant in Sweeney, TX as a prototypical site. The plant has four ethylene production trains, with a total power consumption of 2.4 GW, for an ethylene output of 3.7 million tons per year, 4% of the global ethylene production capacity. This paper proposes replacement of the gas furnaces by low-emission PBMR modules, and presents the safety concerns and risk mitigation and management options for this coupled system. Two coupling design options are proposed, and the necessary changes to the design basis events and severe accidents for the PBMR licensing application are discussed. A joint effort between the chemical and the nuclear entities to optimize the coupling design, establish preventive maintenance procedures, and develop emergency response plans for both of the units is recommended.

  20. Preliminary safety analysis of a PBMR supplying process heat to a co-located ethylene production plant

    Energy Technology Data Exchange (ETDEWEB)

    Scarlat, Raluca O., E-mail: rscarlat@nuc.berkeley.edu [University of California Berkeley, Nuclear Engineering, 4118 Etcheverry Hall, Berkeley, CA 94720 (United States); Cisneros, Anselmo T. [University of California Berkeley, Nuclear Engineering, 4118 Etcheverry Hall, Berkeley, CA 94720 (United States); Koutchesfahani, Tawni [University of California, Chemical and Biomolecular Engineering, 201 Gilman Hall, Berkeley, CA 94720 (United States); Hong, Rada; Peterson, Per F. [University of California Berkeley, Nuclear Engineering, 4118 Etcheverry Hall, Berkeley, CA 94720 (United States)

    2012-10-15

    This paper considers the safety analysis and licensing approach for co-locating a pebble bed modular reactor (PBMR) to provide process heat to an ethylene production unit. The PBMR is an advanced nuclear reactor design that provides 400 MW of thermal energy. Ethylene production is an energy intensive process that utilizes large gas furnaces to provide the heat for the process. Coupling a PBMR with an ethylene production plant would open a new market for nuclear power, and would provide the chemical industry with a cleaner power source, helping to achieve the Clean Air Act standards, and eliminating the 0.5 ton of CO{sub 2} emissions per ton of produced ethylene. Our analysis uses the Chevron Phillips chemical plant in Sweeney, TX as a prototypical site. The plant has four ethylene production trains, with a total power consumption of 2.4 GW, for an ethylene output of 3.7 million tons per year, 4% of the global ethylene production capacity. This paper proposes replacement of the gas furnaces by low-emission PBMR modules, and presents the safety concerns and risk mitigation and management options for this coupled system. Two coupling design options are proposed, and the necessary changes to the design basis events and severe accidents for the PBMR licensing application are discussed. A joint effort between the chemical and the nuclear entities to optimize the coupling design, establish preventive maintenance procedures, and develop emergency response plans for both of the units is recommended.

  1. Analysis of safety information for nuclear power plants and development of source term estimation program

    International Nuclear Information System (INIS)

    Kim, Tae Woon; Choi, Seong Soo; Park, Jin Hee

    1999-12-01

    Current CARE(Computerized Advisory System for Radiological Emergency) in KINS(Korea Institute of Nuclear Safety) has no STES(Source Term Estimation System) which links between SIDS(Safety Information Display System) and FADAS(Following Accident Dose Assessment System). So in this study, STES is under development. STES system is the system that estimates the source term based on the safety information provided by SIDS. Estimated source term is given to FADAS as an input for estimation of environmental effect of radiation. Through this first year project STES for the Kori 3,4 and Younggwang 1,2 has been developed. Since there is no CARE for Wolsong(PHWR) plants yet, CARE for Wolsong is under construction. The safety parameters are selected and the safety information display screens and the alarm logic for plant status change are developed for Wolsong Unit 2 based on the design documents for CANDU plants

  2. A new energy analysis tool for ground source heat pump systems

    Energy Technology Data Exchange (ETDEWEB)

    Michopoulos, A.; Kyriakis, N. [Process Equipment Design Laboratory, Mechanical Engineering Department, Aristotle University of Thessaloniki, POB 487, 541 24 Thessaloniki (Greece)

    2009-09-15

    A new tool, suitable for energy analysis of vertical ground source heat pump systems, is presented. The tool is based on analytical equations describing the heat exchanged with the ground, developed in Matlab {sup registered} environment. The time step of the simulation can be freely chosen by the user (e.g. 1, 2 h etc.) and the calculation time required is very short. The heating and cooling loads of the building, at the afore mentioned time step, are needed as input, along with the thermophysical properties of the soil and of the ground heat exchanger, the operation characteristic curves of the system's heat pumps and the basic ground source heat exchanger dimensions. The results include the electricity consumption of the system and the heat absorbed from or rejected to the ground. The efficiency of the tool is verified through comparison with actual electricity consumption data collected from an existing large scale ground coupled heat pump installation over a three-year period. (author)

  3. Meeting Czechoslovak demands for heat in long-term prospective, especially with regard to nuclear sources

    International Nuclear Information System (INIS)

    Klail, M.

    1988-01-01

    The development was studied of heat demand in the CSSR till the year 2030. The ratio of centralized and decentralized heat supply is currently 60 to 40; in the future a slight increase is expected in the decentralized type of heat supply, mainly as a result of more intensive use of natural gas. In 2030, 710 PU of centralized heat should be produced. A decisive element in meeting the demand will be a growing proportion of combined production of electric power and heat by nuclear power plants. The installed capacity of the nuclear power plants in 2030 should range between 23 and 41 thousand MW, the production of electric power in these plants should be 193 to 238 TWh/y. 109 territorial areas potentially suitable for use of heat from nuclear sources were selected. They were included in 19 regions of which 9 should in the year 2010 be linked to heat supply from nuclear power plants that will be in operation. It is expected that in the year 2030, nuclear sources will supply 250 PU of centralized heat. (Z.M.). 2 tabs., 14 refs

  4. Radiation safety aspects in the use of radiation sources in industrial and heath-care applications

    International Nuclear Information System (INIS)

    Venkat Raj, V.

    2001-01-01

    The principle underlying the philosophy of radiation protection and safety is to ensure that there exists an appropriate standard of protection and safety for humans, without unduly limiting the benefits of the practices giving rise to exposure or incurring disproportionate costs in interventions. To realise these objectives, the International Commission on Radiation Protection (ICRP-60) and IAEA's Safety Series (IAEA Safety Series 120, 1996) have enunciated the following criteria for the application and use of radiation: (1) justification of practices; (2) optimisation of protection; (3) dose limitation and (4) safety of sources. Though these criteria are the basic tenets of radiation protection, the radiation hazard potentials of individual applications vary and the methods to achieve the above mentioned objectives principles are different. This paper gives a brief overview of the various applications of radiation and radioactive sources in India, their radiation hazard perspective and the radiation safety measures provided to achieve the basic radiation protection philosophy. (author)

  5. Safety verification of radiation shielding and heat transfer for a model for dry

    International Nuclear Information System (INIS)

    Yu, Haiyan; Tang, Xiaobin; Wang, Peng; Chen, Feida; Chai, Hao; Chen, Da

    2015-01-01

    Highlights: • New type of dry spent fuel storage was designed. • MC method and FEM were used to verify the reliability of new storage. • Radiation shield and heat transfer both meet IAEA standards: 2 mSv/h, 0.1 mSv/h and 190 °C, 85 °C. • Provided possibilities for future implementation of this type of dry storage. - Abstract: The goal of this research is to develop a type of dry spent fuel storage called CHN-24 container, which could contain an equivalent load of 45 GWD/MTU of spent fuel after 10 years cooling. Basically, radiation shielding performance and safe removal of decay heat, which play important roles in the safety performance, were checked and validated using the Monte Carlo method and finite element analysis to establish the radiation dose rate calculation model and three-dimensional heat transfer model for the CHN-24 container. The dose rates at the surface of the container and at a distance of 1 m from the surface were 0.42 mSv/h and 0.06 mSv/h, respectively. These conform to the International Atomic Energy Agency (IAEA) radioactive material transportation safety standards 2 mSv/h and 0.1 mSv/h. The results shows that the CHN-24 container maintains its structural and material integrity under the condition of normal thermal steady-state heat transfer as well as in case of extreme fire as evinced by transient-state analysis. The temperature inside and on the surface of the container were 150.91 °C and 80 °C under normal storage conditions, which indicated that the design also conform to IAEA heat transfer safety standards of 190 °C and 85 °C

  6. Safety issues related to the intermediate heat storage for the EU DEMO

    Energy Technology Data Exchange (ETDEWEB)

    Carpignano, Andrea [NEMO group, Dipartimento Energia, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino (Italy); Pinna, Tonio [ENEA, 00044 Frascati (Italy); Savoldi, Laura; Sobrero, Giulia; Uggenti, Anna Chiara [NEMO group, Dipartimento Energia, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino (Italy); Zanino, Roberto, E-mail: roberto.zanino@polito.it [NEMO group, Dipartimento Energia, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino (Italy)

    2016-11-01

    Highlights: • IHS affects only the PHTS and the BoP (Balance of Plant). • PIEs list does not change but IHS influences PIEs evolution. • Additional issues to be addressed in PIEs study due to the implementation of HIS. • No safety/operational major obstacles were found for IHS concept. - Abstract: The functional deviations able to compromise system safety in the EU DEMO Primary Heat Transfer System (PHTS) with intermediate heat storage (IHS) based on molten salts are identified and compared to the deviations identified with PHTS without IHS. The resulting safety issues for the Balance of Plant (BoP) have been taken into account. Functional Failure Mode and Effects Analysis (FFMEA) is used to highlight the Postulated Initiating Events (PIE) of incident/accident sequences and to provide some safety insights during the preliminary design. The architecture of the system with IHS does not introduce new PIE with respect to the case without IHS, but it modifies some of them. In particular the two Postulated Initiating Events that are affected by the presence of IHS are the LOCA in the tubes of the HX between primary and intermediate circuit and the loss of heat sink for the first wall or the breeding zone. In fact the IHS introduces some advantages concerning the stability of the secondary circuit, but some weaknesses are associated to the physical-chemical nature of molten salts, especially oxidizing power, corrosive nature and risk of solidification. These issues can be managed in the design by the introduction of new safety functions.

  7. Operational Performance Characterization of a Heat Pump System Utilizing Recycled Water as Heat Sink and Heat Source in a Cool and Dry Climate

    Directory of Open Access Journals (Sweden)

    Piljae Im

    2018-01-01

    Full Text Available The wastewater leaving from homes and businesses contains abundant low-grade energy, which can be utilized through heat pump technology to heat and cool buildings. Although the energy in the wastewater has been successfully utilized to condition buildings in other countries, it is barely utilized in the United States, until recently. In 2013, the Denver Museum of Nature & Science at Denver, the United States implemented a unique heat pump system that utilizes recycled wastewater from a municipal water system to cool and heat its 13,000 m2 new addition. This recycled water heat pump (RWHP system uses seven 105 kW (cooling capacity modular water-to-water heat pumps (WWHPs. Each WWHP uses R-410A refrigerant, has two compressors, and can independently provide either 52 °C hot water (HW or 7 °C chilled water (CHW to the building. This paper presents performance characterization results of this RWHP system based on the measured data from December 2014 through August 2015. The annual energy consumption of the RWHP system was also calculated and compared with that of a baseline Heating, Ventilation, and Air Conditioning (HVAC system which meets the minimum energy efficiencies that are allowed by American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE 90.1-2013. The performance analysis results indicate that recycled water temperatures were favorable for effective operation of heat pumps. As a result, on an annual basis, the RWHP system avoided 50% of source energy consumption (resulting from reduction in natural gas consumption although electricity consumption was increased slightly, reduced CO2 emissions by 41%, and saved 34% in energy costs as compared with the baseline system.

  8. Plastic waste depolymerization as a source of energetic heating oils

    Directory of Open Access Journals (Sweden)

    Wołosiewicz-Głąb Marta

    2017-01-01

    Full Text Available In the past years there has been an increase in production and consumption of plastics, which are widely used in many areas of life. Waste generated from this material are a challenge for the whole of society, regardless of awareness of sustainable development and its technological progress. Still the method of disposal of plastic waste are focused mainly on their storage and incineration, not using energy contained there. In this paper technology for plastic waste depolymerization with characteristics of fuel oil resulting in the process, as an alternative to traditional energy carriers such as: coal, fine coal or coke used in households will be presented. Oil has a high calorific value and no doubt could replace traditional solutions which use conventional energy sources. Furthermore, the fuel resulting from this process is sulfur-free and chemically pure. The paper presents the installation for plastics waste depolymerization used in selected Polish Institute of Plastics Processing, along with the ability to use the main thermocatalytic transformation product.

  9. Demonstration testing and evaluation of in situ soil heating. Health and safety plan (Revision 2)

    Energy Technology Data Exchange (ETDEWEB)

    Dev, H.

    1994-12-28

    This document is the Health and Safety Plan (HASP) for the demonstration of IITRI`s EM Treatment Technology. In this process, soil is heated in situ by means of electrical energy for the removal of hazardous organic contaminants. This process will be demonstrated on a small plot of contaminated soil located in the Pit Area of Classified Burial Ground K-1070-D, K-25 Site, Oak Ridge, TN. The purpose of the demonstration is to remove organic contaminants present in the soil by heating to a temperature range of 85{degrees} to 95{degrees}C. The soil will be heated in situ by applying 60-Hz AC power to an array of electrodes placed in boreholes drilled through the soil. In this section a brief description of the process is given along with a description of the site and a listing of the contaminants found in the area.

  10. Demonstration testing and evaluation of in situ soil heating. Health and safety plan (Revision 2)

    International Nuclear Information System (INIS)

    Dev, H.

    1994-01-01

    This document is the Health and Safety Plan (HASP) for the demonstration of IITRI's EM Treatment Technology. In this process, soil is heated in situ by means of electrical energy for the removal of hazardous organic contaminants. This process will be demonstrated on a small plot of contaminated soil located in the Pit Area of Classified Burial Ground K-1070-D, K-25 Site, Oak Ridge, TN. The purpose of the demonstration is to remove organic contaminants present in the soil by heating to a temperature range of 85 degrees to 95 degrees C. The soil will be heated in situ by applying 60-Hz AC power to an array of electrodes placed in boreholes drilled through the soil. In this section a brief description of the process is given along with a description of the site and a listing of the contaminants found in the area

  11. Sources of Safety Data and Statistical Strategies for Design and Analysis: Postmarket Surveillance.

    Science.gov (United States)

    Izem, Rima; Sanchez-Kam, Matilde; Ma, Haijun; Zink, Richard; Zhao, Yueqin

    2018-03-01

    Safety data are continuously evaluated throughout the life cycle of a medical product to accurately assess and characterize the risks associated with the product. The knowledge about a medical product's safety profile continually evolves as safety data accumulate. This paper discusses data sources and analysis considerations for safety signal detection after a medical product is approved for marketing. This manuscript is the second in a series of papers from the American Statistical Association Biopharmaceutical Section Safety Working Group. We share our recommendations for the statistical and graphical methodologies necessary to appropriately analyze, report, and interpret safety outcomes, and we discuss the advantages and disadvantages of safety data obtained from passive postmarketing surveillance systems compared to other sources. Signal detection has traditionally relied on spontaneous reporting databases that have been available worldwide for decades. However, current regulatory guidelines and ease of reporting have increased the size of these databases exponentially over the last few years. With such large databases, data-mining tools using disproportionality analysis and helpful graphics are often used to detect potential signals. Although the data sources have many limitations, analyses of these data have been successful at identifying safety signals postmarketing. Experience analyzing these dynamic data is useful in understanding the potential and limitations of analyses with new data sources such as social media, claims, or electronic medical records data.

  12. New source terms: what do they tell us about engineered safety feature performance

    International Nuclear Information System (INIS)

    Bernero, R.M.

    1985-01-01

    The accident behavior models which are the basis of engineered safety feature design are generally simple, non-mechanistic and concentrated on volatile radioiodine. Now data from source term studies show that models should be more mechanistic and look at other species than volatile iodine. A complete reevaluation of engineered safety features is needed

  13. The international standard for protection from ionizing radiation and safety of radiation sources

    Energy Technology Data Exchange (ETDEWEB)

    Schlesinger, T [Israel Atomic Energy Commission, Yavne (Israel). Soreq Nuclear Research Center

    1995-06-01

    This document is a review in hebrew of the new 1994 international standard of the IAEA. The new standard title is `Basic safety standards for radiation protection and for the safety of radiation sources`, which were published in the ICRP Pub. 9.

  14. Heat transfer calculations for the High Flux Isotope Reactor (HFIR). Technical specifications: bases for safety limits and limiting safety system settings

    International Nuclear Information System (INIS)

    Sims, T.M.; Swanks, J.H.

    1977-09-01

    Heat transfer analyses, in support of the preparation of the HFIR technical specifications, were made to establish the bases for the safety limits and limiting safety system settings applicable to the HFIR. The results of these analyses, along with the detailed bases, are presented

  15. Viscoelastic Fluid over a Stretching Sheet with Electromagnetic Effects and Nonuniform Heat Source/Sink

    Directory of Open Access Journals (Sweden)

    Kai-Long Hsiao

    2010-01-01

    Full Text Available A magnetic hydrodynamic (MHD of an incompressible viscoelastic fluid over a stretching sheet with electric and magnetic dissipation and nonuniform heat source/sink has been studied. The buoyant effect and the electric number E1 couple with magnetic parameter M to represent the dominance of the electric and magnetic effects, and adding the specific item of nonuniform heat source/sink is presented in governing equations which are the main contribution of this study. The similarity transformation, the finite-difference method, Newton method, and Gauss elimination method have been used to analyze the present problem. The numerical solutions of the flow velocity distributions, temperature profiles, and the important wall unknown values of f''(0 and θ'(0 have been carried out. The parameter Pr, E1, or Ec can increase the heat transfer effects, but the parameter M or A* may decrease the heat transfer effects.

  16. Main design and safety features of a 200MW nuclear heating reactor

    International Nuclear Information System (INIS)

    Zheng, Wenxiang; Gao, Zuying; Wang, Dazhong

    1992-01-01

    Inept has been in charge of the development of a nuclear heating reactor since 1980s, which is one of the national key R and D Programs in China. A 5MWt experimental NCR was completed at Inept in 1989 and has operated successfully for space heating since then. In order to realize the commercialization of the NCR, it has been decided to construct a 200MW demonstration NCR in 1993. A number of advanced features, including natural circulation, integrated arrangement, self-pressurized performance, dual vessel structure, hydraulic control rod drive and passive safety systems, have been incorporated into the NCR-200 to achieve its safety goal and economic viability. This makes the NCR safe, simple, reliable, easy-constructed and maintained. At present, the design work of the NCR-200 have shown that its safety characteristics are excellent. The NCR could play an important role in resolving future energy and environmental problems in China. The paper will mainly cover the key design considerations, main technical features and safety analysis results of the NCR-200

  17. Advanced neutron source reactor conceptual safety analysis report, three-element-core design: Chapter 15, accident analysis

    International Nuclear Information System (INIS)

    Chen, N.C.J.; Wendel, M.W.; Yoder, G.L.; Harrington, R.M.

    1996-02-01

    In order to utilize reduced enrichment fuel, the three-element-core design for the Advanced Neutron Source has been proposed. The proposed core configuration consists of inner, middle, and outer elements, with the middle element offset axially beneath the inner and outer elements, which are axially aligned. The three-element-core RELAP5 model assumes that the reactor hardware is changed only within the core region, so that the loop piping, heat exchangers, and pumps remain as assumed for the two-element-core configuration. To assess the impact of changes in the core region configuration and the thermal-hydraulic steady-state conditions, the safety analysis has been updated. This report gives the safety margins for the loss-of-off-site power and pressure-boundary fault accidents based on the RELAP5 results. AU margins are greater for the three-element-core simulations than those calculated for the two-element core

  18. ECOLOGICAL SAFETY OF MINING REGIONS THROUGH CREATION OF POWER‐HEATING COMPLEXES (in Russian

    Directory of Open Access Journals (Sweden)

    I. A. YEFREMOV

    2014-04-01

    Full Text Available There was presented a method of use of alterative source of energy, namely coal mine methane, the use of which as a fuel for power and heatiing generation is a main direction in coal mines. By this means some ecological problems of the region are solved. Highly efficient power and heating technologies are implemented and energy complexes are established.

  19. Analysis of Fuel Cell Driven Ground Source Heat Pump Systems in Community Buildings

    Directory of Open Access Journals (Sweden)

    Jong-Keun Shin

    2013-05-01

    Full Text Available In the present study, a fuel cell driven ground source heat pump (GSHP system is applied in a community building and heat pump system performance is analyzed by computational methods. Conduction heat transfer between the brine pipe and ground is analyzed by TEACH code in order to predict the performance of the heat pump system. The predicted coefficient of performance (COP of the heat pump system and the energy cost were compared with the variation of the location of the objective building, the water saturation rate of the soil, and the driven powers of the heat pump system. Compared to the late-night electricity driven system, a significant reduction of energy cost can be accomplished by employing the fuel cell driven heat pump system. This is due to the low cost of electricity production of the fuel cell system and to the application of the recovered waste heat generated during the electricity production process to the heating of the community building.

  20. A parametric study of a humidification dehumidification (HDH) desalination system using low grade heat sources

    International Nuclear Information System (INIS)

    He, W.F.; Han, D.; Yue, C.; Pu, W.H.

    2015-01-01

    Highlights: • The HDH desalination system coupling with the waste heat plate LGHC is proposed. • Performance of the desalination system and the plate LGHC is presented. • Influence from the operation pressure on the system performance is investigated. • Gained investment ratio is proposed to characterize the desalination system consumption. - Abstract: Humidification dehumidification (HDH) desalination system is applicable to recover the low grade heat source to heat the seawater before the humidifier. In the paper, plate heat exchangers are integrated to recover the waste heat from the exhaust in the water heated closed air open water (CAOW) HDH desalination system. The performance of the HDH desalination system as well as the plate type of low grade heat collector (LGHC) is investigated at different operation pressures. Gain investment ratio (GIR) is proposed and defined to depict the overall consumption of the whole system. The simulation results show that the modified heat capacity ratio of the dehumidifier (HCRd) is vital for the performance of the HDH desalination system as well as the plate LGHC with a top value of gain output ratio (GOR) at the balance point, HCRd = 1, and the maximum GOR, GOR = 2.44, results from the raised pressure of p = 0.15 MPa. Furthermore, taking the cost for the heat transfer surface area of the LGHC and the air and seawater pipes into consideration, it is revealed that the conditions, HCRd > 1, are more economical due to the increase of GIR, which indicates the profit of unit consumption is more significant.

  1. Building competence in radiation protection and the safe use of radiation sources. Safety guide (Spanish ed.)

    International Nuclear Information System (INIS)

    2010-01-01

    This Safety Guide makes recommendations concerning the building of competence in protection and safety within a national radiation protection infrastructure and provides guidance for setting up the structure for a national strategy. It relates to the training and assessment of qualification of new personnel and the retraining of existing personnel in order to develop and maintain appropriate levels of competence. It provides the necessary guidance to meet the requirements laid down in Safety Series No. 115, International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources. Contents: 1. Introduction; 2. Responsibilities for building competence in protection and safety; 3. Education, training and work experience; 4. A national strategy for building competence in protection and safety.

  2. Building competence in radiation protection and the safe use of radiation sources. Safety guide (Arabic ed.)

    International Nuclear Information System (INIS)

    2006-01-01

    This Safety Guide makes recommendations concerning the building of competence in protection and safety within a national radiation protection infrastructure and provides guidance for setting up the structure for a national strategy. It relates to the training and assessment of qualification of new personnel and the retraining of existing personnel in order to develop and maintain appropriate levels of competence. It provides the necessary guidance to meet the requirements laid down in Safety Series No. 115, International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources. Contents: 1. Introduction; 2. Responsibilities for building competence in protection and safety; 3. Education, training and work experience; 4. A national strategy for building competence in protection and safety.

  3. Study of radiation heating (part 1). UR spectroscopic characteristics of radiant heat source

    Energy Technology Data Exchange (ETDEWEB)

    Nagaoka, Yoshikazu; Ajisaka, Kazuhiro; Toyonaga, Hajime; Kitahata, Hiroki; Oshida, Shun' ichi; Sugihara, Tomonori

    1987-09-01

    There are many IR permeable substances. When this is heated with IR beam, UR beam penetrated into the substance and heat up the substance from the inside. In this case, the inside gets hot quicker than the surface which gives much difference in the finish of the product. Characteristics of permeation and absorption of the IR beam vary by the type of the substance and the wave-length of the UR beam. Examples of effectiveness of far infra-red heater are: Baking of rice cake. Baking of PVC granules as a slip-stop for a working gloves. Far infra-red sauna (sweating effect around 50/sup 0/C). Tokyo Gas Co., Ltd. and other companies introduced an IR spectroscopic radiometer of Minarad Systems of USA to establish a data exchange system in 1984. The spectroscopic radio-meter system consists of 3 components, i.e., a spectrophotometric radiometer, a black body furnace, and a computer for data processing. (14 figs, 5 tabs)

  4. Evaluating the use of renewable fuel sources to heat flue-cured tobacco barns

    OpenAIRE

    Brown, Robert T

    2018-01-01

    Evaluating the use of renewable fuel sources to heat flue-cured tobacco barns Robert Taylor Brown ABSTRACT The curing of flue-cured tobacco (Nicotiana tabacum L.) is an energy intensive process and represents a significant portion of the overall cost of production. Given the goal of the industry to reduce the environmental footprint of tobacco production and the energy demand of curing, attention has been directed to explore options for the use of renewable fuels for heating to...

  5. Heat transmission systems for heating and potable water. New requirements and problem solutions for hygiene, safety and improved heat utilization. Waermeuebertragungssysteme fuer Heizung und Trinkwasser. Neue Anforderungen und Problemloesungen bezueglich Hygiene, Sicherheit und besserer Waermenutzung

    Energy Technology Data Exchange (ETDEWEB)

    Kremer, R

    1989-10-01

    In the past, additional demands were made on heat transmission systems regarding hygienic requirements in potable water heating plant for hospitals, hotels, sanatoriums and old-age homes, safety requirements to protect the potable water from the penetration of hazardous substances and requirements for improved heat utilization through return flow cooling and condensate cooling in the district heating. Where potable water heaters are concerned, safety radiators for heat transfer which comply with the requirements of DIN 1988 Part 2 and Part 4, as well as water heaters with permanent disinfection which are legionnaires' disease-proof, are now available for use in hospitals, old age homes and sanatoriums. For the district heating sector, improved range systems with low concentration in the hot water sector as well as condensate heat utilizing systems have been further developed in the steam heating sector. (orig.).

  6. Revenue sources for financing transportation safety activities in Virginia : phase two, state sources.

    Science.gov (United States)

    1980-01-01

    Senate Bill 85, an action of the 1978 General Assembly, amended the Code of Virginia to provide, in part, that the Division of Highway Safety be succeeded by the newly created Department of Transportation Safety effective July 1, 1978. In its Declara...

  7. A model predictive framework of Ground Source Heat Pump coupled with Aquifer Thermal Energy Storage System in heating and cooling equipment of a building

    NARCIS (Netherlands)

    Rostampour Samarin, V.; Bloemendal, J.M.; Keviczky, T.

    2017-01-01

    This paper presents a complete model of a building heating and cooling equipment and a ground source heat pump (GSHP) coupled with an aquifer thermal energy storage (ATES) system. This model contains detailed
    mathematical representations of building thermal dynamics, ATES system dynamics, heat

  8. Sources of Safety Data and Statistical Strategies for Design and Analysis: Clinical Trials.

    Science.gov (United States)

    Zink, Richard C; Marchenko, Olga; Sanchez-Kam, Matilde; Ma, Haijun; Jiang, Qi

    2018-03-01

    There has been an increased emphasis on the proactive and comprehensive evaluation of safety endpoints to ensure patient well-being throughout the medical product life cycle. In fact, depending on the severity of the underlying disease, it is important to plan for a comprehensive safety evaluation at the start of any development program. Statisticians should be intimately involved in this process and contribute their expertise to study design, safety data collection, analysis, reporting (including data visualization), and interpretation. In this manuscript, we review the challenges associated with the analysis of safety endpoints and describe the safety data that are available to influence the design and analysis of premarket clinical trials. We share our recommendations for the statistical and graphical methodologies necessary to appropriately analyze, report, and interpret safety outcomes, and we discuss the advantages and disadvantages of safety data obtained from clinical trials compared to other sources. Clinical trials are an important source of safety data that contribute to the totality of safety information available to generate evidence for regulators, sponsors, payers, physicians, and patients. This work is a result of the efforts of the American Statistical Association Biopharmaceutical Section Safety Working Group.

  9. Sources of Safety Data and Statistical Strategies for Design and Analysis: Transforming Data Into Evidence.

    Science.gov (United States)

    Ma, Haijun; Russek-Cohen, Estelle; Izem, Rima; Marchenko, Olga V; Jiang, Qi

    2018-03-01

    Safety evaluation is a key aspect of medical product development. It is a continual and iterative process requiring thorough thinking, and dedicated time and resources. In this article, we discuss how safety data are transformed into evidence to establish and refine the safety profile of a medical product, and how the focus of safety evaluation, data sources, and statistical methods change throughout a medical product's life cycle. Some challenges and statistical strategies for medical product safety evaluation are discussed. Examples of safety issues identified in different periods, that is, premarketing and postmarketing, are discussed to illustrate how different sources are used in the safety signal identification and the iterative process of safety assessment. The examples highlighted range from commonly used pediatric vaccine given to healthy children to medical products primarily used to treat a medical condition in adults. These case studies illustrate that different products may require different approaches, and once a signal is discovered, it could impact future safety assessments. Many challenges still remain in this area despite advances in methodologies, infrastructure, public awareness, international harmonization, and regulatory enforcement. Innovations in safety assessment methodologies are pressing in order to make the medical product development process more efficient and effective, and the assessment of medical product marketing approval more streamlined and structured. Health care payers, providers, and patients may have different perspectives when weighing in on clinical, financial and personal needs when therapies are being evaluated.

  10. Failure analysis of radioisotopic heat source capsules tested under multi-axial conditions

    International Nuclear Information System (INIS)

    Zielinski, R.E.; Stacy, E.; Burgan, C.E.

    In order to qualify small radioisotopic heat sources for a 25-yr design life, multi-axial mechanical tests were performed on the structural components of the heat source. The results of these tests indicated that failure predominantly occurred in the middle of the weld ramp-down zone. Examination of the failure zone by standard metallographic techniques failed to indicate the true cause of failure. A modified technique utilizing chemical etching, scanning electron microscopy, and energy dispersive x-ray analysis was employed and dramatically indicated the true cause of failure, impurity concentration in the ramp-down zone. As a result of the initial investigation, weld parameters for the heat sources were altered. Example welds made with a pulse arc technique did not have this impurity buildup in the ramp-down zone

  11. Heat source component development program. Report for July--December 1978

    International Nuclear Information System (INIS)

    Foster, E.L. Jr.

    1979-01-01

    This is the seventh of a series of reports describing the results of several analytical and experimental programs being conducted at Battelle-Columbus Laboratories to develop components for advanced radioisotope heat source applications. The heat sources will for the most part be used in advanced static and dynamic power conversion systems. Battelle's support of LASL during the current reporting period has been to determine the operational and reentry response of selected heat source trial designs, and their thermal response to a space shuttle solid propellant fire environment. Thermal, ablation, and thermal stress analyses were conducted using two-dimensional modeling techniques previously employed for the analysis of the earlier trial design versions, and modified in part to improve the modeling accuracy. Further modifications were made to improve the modeling accuracy as described herein. Thermal, ablation, and thermal stress analyses were then conducted for the trial design selected by LASL/DOE for more detailed studies using three-dimensional modeling techniques

  12. Negative hydrogen ion beam extraction from an AC heated cathode driven Bernas-type ion source

    Energy Technology Data Exchange (ETDEWEB)

    Okano, Y.; Miyamoto, N.; Kasuya, T.; Wada, M.

    2015-04-08

    A plasma grid structure was installed to a Bernas-type ion source used for ion implantation equipment. A negative hydrogen (H{sup −}) ion beam was extracted by an AC driven ion source by adjusting the bias to the plasma grid. The extracted electron current was reduced by positively biasing the plasma grid, while an optimum plasma grid bias voltage for negative ion beam extraction was found to be positive 3 V with respect to the arc chamber. Source operations with AC cathode heating show extraction characteristics almost identical to that with DC cathode heating, except a minute increase in H{sup −} current at higher frequency of cathode heating current.

  13. Whole planet cooling and the radiogenic heat source contents of the earth and moon

    International Nuclear Information System (INIS)

    Schubert, G.; Stevenson, D.

    1980-01-01

    It is widely believed that the surface heat flows of the earth and moon provide good measures of the total amounts of radioactives in these bodies. Simple thermal evolution models, based on subsolidus whole mantle convection, indicate that this may not be the case. These models have been constructed assuming an initially hot state, but with a wide variety of choices for the parameters characterizing the rheology and convective vigor. All models are constrained to be consistent with present-day surface heat fluxes, and many of the terrestrial models are consistent with the mantle viscosities indicated by post-glacial rebound. For the earth the acceptable models give a radiogenic heat production that is only 65--85% of the surface heat output, the difference being due to secular cooling of the earth (about 50 0 --100 0 C per 10 9 years in the upper mantle). It is argued that the actual heat generation may be substantially less, since the models omit core heat, upward migration of heat sources, possible layering of the mantle, and deviations from steady convection. Geochemical models which are near to chondritic (apart from potassium depletion) are marginally consistent with surface heat flow. In the lunar models, heat generation is typically only 70--80% of the surface heat flow, even with allowance for the strong near-surface enhancement of radioactives. Despite the simplicity of the models the persistence of a significant difference between heat generation and heat output for a wide range of parameter choices indicates that this difference is real and should be incorporated in geochemical modeling of the planets

  14. Performance analysis and experimental study of heat-source tower solution regeneration

    International Nuclear Information System (INIS)

    Liang, Caihua; Wen, Xiantai; Liu, Chengxing; Zhang, Xiaosong

    2014-01-01

    Highlights: • Theoretical analysis is performed on the characteristics of heat-source tower. • Experimental study is performed on various rules of the solution regeneration rate. • The characteristics of solution regeneration vary widely with different demands. • Results are useful for optimizing the process of solution regeneration. - Abstract: By analyzing similarities and difference between the solution regeneration of a heat-source tower and desiccant solution regeneration, this paper points out that solution regeneration of a heat-source tower has the characteristics of small demands and that a regeneration rate is susceptible to outdoor ambient environments. A theoretical analysis is performed on the characteristics of a heat-source tower solution in different outdoor environments and different regeneration modes, and an experimental study is performed on variation rules of the solution regeneration rate of a cross-flow heat-source tower under different inlet parameters and operating parameters. The experimental results show that: in the operating regeneration mode, as the air volume was increased from 123 m 3 h −1 to 550 m 3 h −1 , the system heat transfer amount increased from 0.42 kW to 0.78 kW, and the regeneration rate increased from 0.03 g s −1 to 0.19 g s −1 . Increasing the solution flow may increase the system heat transfer amount; however, the regeneration rate decreased to a certain extent. In the regeneration mode when the system is idle, as the air volume was increased from 136 m 3 h −1 to 541 m 3 h −1 , the regeneration rate increased from 0.03 g s −1 to 0.1 g s −1 . The regeneration rate almost remained unchanged around 0.07 g s −1 as the solution flow is increased. In the regeneration mode with auxiliary heat when the system is idle, increasing the air volume and increasing the solution flow required more auxiliary heat, thereby improving the solution regeneration rate. As the auxiliary heat was increased from 0.33 k

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

    International Nuclear Information System (INIS)

    Bourke, Grant; Bansal, Pradeep

    2010-01-01

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

  16. Disruption simulation experiment using high-frequency rastering electron beam as the heat source

    International Nuclear Information System (INIS)

    Yamazaki, S.; Seki, M.

    1987-01-01

    The disruption is a serious event which possibly reduces the lifetime of plasm interactive components, so the effects of the resulting high heat flux on the wall materials must be clearly identified. The authors performed disruption simulation experiments to investigate melting, evaporation, and crack initiation behaviors using an electron beam facility as the heat source. The facility was improved with a high-frequency beam rastering system which provided spatially and temporally uniform heat flux on wider test surfaces. Along with the experiments, thermal and mechanical analyses were also performed. A two-dimensional disruption thermal analysis code (DREAM) was developed for the analyses

  17. Energy from Waste: Reuse of Compost Heat as a Source of Renewable Energy

    Directory of Open Access Journals (Sweden)

    G. Irvine

    2010-01-01

    Full Text Available An in-vessel tunnel composting facility in Scotland was used to investigate the potential for collection and reuse of compost heat as a source of renewable energy. The amount of energy offered by the compost was calculated and seasonal variations analysed. A heat exchanger was designed in order to collect and transfer the heat. This allowed heated water of 47.3oC to be obtained. The temperature could be further increased to above 60oC by passing it through multiple tunnels in series. Estimated costs for installing and running the system were calculated. In order to analyse these costs alternative solar thermal and ground source heat pump systems were also designed. The levels of supply and economic performance were then compared. A capital cost of £11,662 and operating cost of £1,039 per year were estimated, resulting in a cost of £0.50 per kWh for domestic water and £0.10 per kWh for spatial heat. Using the heat of the compost was found to provide the most reliable level of supply at a similar price to its rivals.

  18. Air source integrated heat pump simulation model for EnergyPlus

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Bo; New, Joshua; Baxter, Van

    2017-12-01

    An Air Source Integrated Heat Pump (AS-IHP) is an air source, multi-functional spacing conditioning unit with water heating function (WH), which can lead to great energy savings by recovering the condensing waste heat for domestic water heating. This paper summarizes development of the EnergyPlus AS-IHP model, introducing the physics, sub-models, working modes, and control logic. Based on the model, building energy simulations were conducted to demonstrate greater than 50% annual energy savings, in comparison to a baseline heat pump with electric water heater, over 10 US cities, using the EnergyPlus quick-service restaurant template building. We assessed water heating energy saving potentials using AS-IHP versus both gas and electric baseline systems, and pointed out climate zones where AS-IHPs are promising. In addition, a grid integration strategy was investigated to reveal further energy saving and electricity cost reduction potentials, via increasing the water heating set point temperature during off-peak hours and using larger water tanks.

  19. Design and application for a high-temperature nuclear heat source

    International Nuclear Information System (INIS)

    Quade, R.N.

    1980-01-01

    Recent actions by OPEC have sharply increased interest in the United States in synfuels, with coal being the logical choice for the carbon source. Two coal liquefaction processes, direct and indirect, have been examined. Each can produce about 50% more output when coupled to an HTGR for process heat. The nuclear reactor designed for process heat has a power output of 842MW(t), a core outlet temperature of 950 0 C (1742 0 F), and an intermediate helium loop to separate the heat source from the process heat exchangers. Steam-methane reforming is the reference process. As part of the development of a nuclear process heat system, a computer code, Process Heat Reactor Evaluation and Design, is being developed. This code models both the reactor plant and a steam reforming plant. When complete, the program will have the capability to calculate an overall mass and heat balance, size the plant components, and estimate the plant cost for a wide variety of independent variables. (author)

  20. Thermal-hydraulic process for cooling, heating and power production with low-grade heat sources in residential sector

    International Nuclear Information System (INIS)

    Borgogno, R.; Mauran, S.; Stitou, D.; Marck, G.

    2017-01-01

    Highlights: • Assessment of solar thermal-hydraulic process for tri-generation application. • Choice of the most suitable working fluid pair (R1234yf/R1233zd). • Evaluation of the global annual performance in Mediterranean climate. • Global annual COP and heat amplification achieving 0.24 and 1.2 respectively. • Global annual performance achieving an electric efficiency of 3.7%. - Abstract: A new process based on thermal-hydraulic conversion actuated by low-grade thermal energy is investigated. Input thermal energy can be provided by the means of solar collectors, as well as other low temperature energy sources. In the following article, “thermo-hydraulic” term refers to a process involving an incompressible fluid used as an intermediate medium to transfer work hydraulically between different thermal operated components or sub-systems. The system aims at providing trigeneration energy features for the residential sector, that is providing heating, cooling and electrical power for meeting the energy needs of domestic houses. This innovative system is made of two dithermal processes (working at two different levels of temperatures) and featuring two different working fluids. The first process is able to directly supply either electrical energy generated by an hydraulic turbine or drives the second process thanks to the incompressible fluid, which is similar to a heat pump effect for heating or cooling purposes. The innovative aspect of this process relies on the use of an hydraulic transfer fluid to transfer the work between each sub-system and therefore simplifying the conversion chain. A model, assuming steady-state operation, is developed to assess the energy performances of different variants of this thermo-hydraulic process with various heat source temperatures (80–110 °C) or heat sinks (0–30 °C), as well as various pairs of working fluids. For instance, in the frame of a single-family home, located in the Mediterranean region, the working

  1. Experimental research on novel adsorption chiller driven by low grade heat source

    International Nuclear Information System (INIS)

    Wang, D.C.; Shi, Z.X.; Yang, Q.R.; Tian, X.L.; Zhang, J.C.; Wu, J.Y.

    2007-01-01

    A novel silica gel-water adsorption chiller is developed. This chiller consists of three vacuum chambers: two adsorption/desorption (or evaporation/condensation) vacuum chambers and one heat pipe working vacuum chamber. In this chiller, only one vacuum valve is installed between the two adsorption/desorption vacuum chambers to improve its performance when it is driven by a low temperature heat source. The operational reliability of the chiller is highly improved because of fewer moving parts. In this work, the performance of the chiller is experimentally tested under a low grade heat source, such as 55-67 o C. The test results show that the performance of this chiller is satisfying when it is driven by a low grade heat source, such as 65 o C, and the cooling capacity (or refrigeration capacity) will reach about 5 kW when the hot water temperature is 65 o C, the cooling water temperature is 30.5 o C and the chilled water inlet temperature is 15.1 o C. The test results confirm that this kind of adsorption chiller can be effectively driven by a low grade heat source

  2. Thermal modeling of multi-shape heating sources on n-layer electronic board

    Directory of Open Access Journals (Sweden)

    Monier-Vinard Eric

    2017-01-01

    Full Text Available The present work completes the toolbox of analytical solutions that deal with resolving steady-state temperatures of a multi-layered structure heated by one or many heat sources. The problematic of heating sources having non-rectangular shapes is addressed to enlarge the capability of analytical approaches. Moreover, various heating sources could be located on the external surfaces of the sandwiched layers as well as embedded at interface of its constitutive layers. To demonstrate its relevance, the updated analytical solution has been compared with numerical simulations on the case of a multi-layered electronic board submitted to a set of heating source configurations. The comparison shows a high agreement between analytical and numerical calculations to predict the centroid and average temperatures. The promoted analytical approach establishes a kit of practical expressions, easy to implement, which would be cumulated, using superposition principle, to help electronic designers to early detect component or board temperatures beyond manufacturer limit. The ability to eliminate bad concept candidates with a minimum of set-up, relevant assumptions and low computation time can be easily achieved.

  3. The IAEA's sub programme on the safety of radiation sources and the security of radioactive materials

    International Nuclear Information System (INIS)

    Ortiz, P.; Oresegun, M.; Bilbao, A.; Webb, G.A.M.; Cunninghan, R.

    1998-01-01

    In compliance with its mandate to establish standards of safety and to provide for their application with respect to radiation sources, the International Atomic Energy Agency has developed a subprogramme aimed at providing Member States guidance and assistance on achieving regulatory control and the safe use of the sources. The guidance addresses the establishment of a Regulatory Programme, with focus on a system for notification and authorization (registration and licensing) and inspection of radiation sources, including check lists for review of safety. It also includes methods for assessing its effectiveness of the Regulatory Programme and is complemented with tools for the management of data by the Regulatory Authority and Services to assist Member States in assessment and implementation of the programme. In addition, technical guidance for the safety of radiation sources includes both prospective and retrospective safety assessment. Retrospective methods have been used resulting in the publication and dissemination of information and lessons from accidents, both individual accident reports and lessons from collection of accident for the practices with major sources (industrial radiography, irradiators and radiotherapy). Prospective methods will include guidance on the application of the principles of radiation protection to potential exposure, as well as methods to apply the principles, such as identification and evaluation of scenarios. Practice specific reports will address the major radiation sources. A research programme will be dedicated to apply Probabilistic Safety Assessment (PSA) to radiation sources. (author)

  4. Strengthening the safety and security of radioactive sources worldwide: a perspective on Philippine contributions

    International Nuclear Information System (INIS)

    Murray, Allan

    2009-01-01

    Radioactive sources have been used for many decades in a wide variety of applications in all countries. The safety of radioactive sources and the associated radiation protection have been implemented by national and international programs during this time with cooperation through the IAEA intended to achieve application of minimum standards and harmonization of approach. The security of radioactive sources is however relatively new consideration. A perspective on the Philippine contributions to the safety and security of radioactive sources will be provided with reference to the following: What is radioactive source security and why it is important?; International cooperation, including the IAEA Code of Conduct; Regulation for radioactive source security; Implementation of radioactive source security measures for licenses, operators and others; Impact of regulatory and operational matters such as professional development and training, emergency preparedness and response, and radiation protection. (author)

  5. Suppression of cyclotron instability in Electron Cyclotron Resonance ion sources by two-frequency heating

    International Nuclear Information System (INIS)

    Skalyga, V.; Izotov, I.; Mansfeld, D.; Kalvas, T.; Koivisto, H.; Komppula, J.; Kronholm, R.; Laulainen, J.; Tarvainen, O.

    2015-01-01

    Multiple frequency heating is one of the most effective techniques to improve the performance of Electron Cyclotron Resonance (ECR) ion sources. The method increases the beam current and average charge state of the extracted ions and enhances the temporal stability of the ion beams. It is demonstrated in this paper that the stabilizing effect of two-frequency heating is connected with the suppression of electron cyclotron instability. Experimental data show that the interaction between the secondary microwave radiation and the hot electron component of ECR ion source plasmas plays a crucial role in mitigation of the instabilities

  6. Comparing costs of power and heat production by prospective and present sources

    International Nuclear Information System (INIS)

    Novak, S.

    1979-01-01

    Capital and running costs are compared of power and heat production from different sources. The lowest capital costs were found for coal-fired power plants followed by light water reactor power plants. The capital costs of other types of power plants, such as wind, geothermal, solar, thermonuclear power plants are significantly higher. The estimated specific cost for electric power production in 1985 for a nuclear power plant is lower than for a fossil-fuel power plant. It is estimated that in 1985 coal will be the cheapest heat source. (Ha)

  7. Design of CAREM-25 Residual Heat Removal System: Nuclear Safety Aspects

    International Nuclear Information System (INIS)

    Zanocco, Pablo; Gimenez, Marcelo; Schlamp, Miguel; Barrera, M.

    2000-01-01

    In this paper Carem-25 residual heat removal system (RHRS) design is analyzed from the nuclear safety point of view.The proposed RHRS is a condenser that transfers the heat to a pool located in the upper level of the containment.The RHRS design basis accident is a reactor loss of heat sink.The following requirements were settled to be verified: a) To remove 2 MW, for a primary circuit pressure of 12.25 MPa and a pool temperature of 100 0 C. b) No condenser tubes flooding, for a primary circuit pressure of 14 MPa and a pool temperature of 100 0 C. c) To reach hot shutdown in 48-hrs, that is to remove of 0.6 MW for a primary circuit pressure of 2.3 MPa and a pool temperature of 120 0 C.Heat transfer regimes inside and outside the condenser and flow patterns were analyzed.Steady state conditions for the above design conditions were modeled.The design requirements were verified taking into account heat transfer coefficients uncertainties and their propagation to the equipment elevation in the containment over the RPV, in order to minimize its elevation and its possible flooding.The resulting condenser tubes were 2 S CH 160 TP 347 SS, with a total area of 4 m 2 and a required minimum height of 6 m from the RPV water level to the condenser outlet headers

  8. Overview of waste isoltaion safety assessment program and description of source term characterization task at PNL

    International Nuclear Information System (INIS)

    Bradley, D.

    1977-01-01

    A project is being conducted to develop and illustrate the methods and obtain the data necessary to assess the safety of long-term disposal of high-level radioactive waste in geologic formations. The methods and data will initially focus on generic geologic isolation systems but will ultimately be applied to the long-term safety assessment of specific candidate sites that are selected in the NWTS Program. The activities of waste isolation safety assessment (WISAP) are divided into six tasks: (1) Safety Assessment Concepts and Methods, (2) Disruptive Event Analysis, (3) Source Characterization, (4) Transport Modeling, (5) Transport Data and (6) Societal Acceptance

  9. BRIGITTE, Dose Rate and Heat Source and Energy Flux for Self-Absorbing Rods

    International Nuclear Information System (INIS)

    Jegu, M.; Clement, M.

    1978-01-01

    1 - Nature of physical problem solved: Calculation of dose rate, heat sources or energy flux. The sources are self-absorbing radioactive rods. The shielding consists of blocks of which the cross section can be defined. 2 - Method of solution: Exponential attenuation and build-up factor between source points and detector points. Source integration with error estimate. Automatic or controlled build-up with monitor print-out. 3 - Restrictions on the complexity of the problem: Number of energy points, regions, detector points, abscissa points of the rod, vertical position of the rod, are all limited to ten. The maximum total number of vertical steps is 124

  10. Radiation safety aspects of fluorescent lamp starters incorporating radiation source

    Energy Technology Data Exchange (ETDEWEB)

    Sadagopan, Geetha [Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Trombay, Mumbai (India); Shukla, V.K. [Environmental Assessment Division, Bhabha Atomic Research Centre, Trombay, Mumbai (India)

    2000-05-01

    A fluorescent lamp starter is a switch applies the voltage to the fluorescent tube after sufficient preheating to allow the tube to conduct an electric current. Radioactive substances used in the starters are {sup 85}Kr, {sup 147}Pm, {sup 3}H and {sup 232}Th. In India, fluorescent lamp starters are classified as consumer products and users are outside regulatory control. However, regulatory control is exercised over the manufacturers at the production stage. Tritium activity measured in the lamp starters ranged from 400-4500 Bq with a mean activity of 1.78 kBq. Thorium activity measured varied from 0.44-3.3 mg. The results of radiation safety assessment of the workplace and radioactivity estimation in the starters are discussed in this paper. (author)

  11. Radiation safety aspects of fluorescent lamp starters incorporating radiation source

    International Nuclear Information System (INIS)

    Sadagopan, Geetha; Shukla, V.K.

    2000-01-01

    A fluorescent lamp starter is a switch applies the voltage to the fluorescent tube after sufficient preheating to allow the tube to conduct an electric current. Radioactive substances used in the starters are 85 Kr, 147 Pm, 3 H and 232 Th. In India, fluorescent lamp starters are classified as consumer products and users are outside regulatory control. However, regulatory control is exercised over the manufacturers at the production stage. Tritium activity measured in the lamp starters ranged from 400-4500 Bq with a mean activity of 1.78 kBq. Thorium activity measured varied from 0.44-3.3 mg. The results of radiation safety assessment of the workplace and radioactivity estimation in the starters are discussed in this paper. (author)

  12. Strengthening of safety and security of radioactive sources: new regulatory challenges

    Energy Technology Data Exchange (ETDEWEB)

    El Messaoudi, M.; Essadki M Lferde, H.; Moutia, Z. [Faculte des Sciences, Dept. de Physique, Rabat (Morocco)

    2006-07-01

    The answer to these new regulatory challenges was given by implementation of divers measures aimed at strengthening of safety and security of radioactive sources and to prevent the malevolent use of radioactive sources. The international basic safety standards for protection against ionizing radiation and for the safety of radiation sources (B.S.S.) require the establishment and implementation of security measures of radioactive sources to ensure that protection and safety requirements are met. The IAEA has engaged in an extensive effort to establish and/or strengthen national radiation protection and radiological safety infrastructure, including legislation and regulation, a regulatory authority empowered to authorize and inspect regulated activities, an adequate number of trained personnel and technical services that are beyond the capabilities required of the authorized legal persons. The Moroccan authority makes steady efforts to strengthen national radiation safety infrastructure by participating in IAEA model project for upgrading radiation protection infrastructure, to implement the revised version of code of conduct on the safety and security of radioactive sources. Indeed, Morocco expressed its adhesion with the technical assistance project of the IAEA in 2001, carrying on the reinforcement of the national infrastructure of regulation and control of the radioactive materials. The control over radioactive sources is an essential element for maintaining high level of security and safety of radioactive sources. The IAEA T.E.C.-D.O.C.-1388 serves as reference document to implement the control culture. The security problems with which the world is confronted showed that the uses of radioactive sources should subject reinforcements of safety, of control and of security of the radioactive sources. For this purpose, the IAEA launched an action plan for the safety and security of radioactive sources. The IAEA guide Security of radioactive sources will help the

  13. Strengthening of safety and security of radioactive sources: new regulatory challenges

    International Nuclear Information System (INIS)

    El Messaoudi, M.; Essadki M Lferde, H.; Moutia, Z.

    2006-01-01

    The answer to these new regulatory challenges was given by implementation of divers measures aimed at strengthening of safety and security of radioactive sources and to prevent the malevolent use of radioactive sources. The international basic safety standards for protection against ionizing radiation and for the safety of radiation sources (B.S.S.) require the establishment and implementation of security measures of radioactive sources to ensure that protection and safety requirements are met. The IAEA has engaged in an extensive effort to establish and/or strengthen national radiation protection and radiological safety infrastructure, including legislation and regulation, a regulatory authority empowered to authorize and inspect regulated activities, an adequate number of trained personnel and technical services that are beyond the capabilities required of the authorized legal persons. The Moroccan authority makes steady efforts to strengthen national radiation safety infrastructure by participating in IAEA model project for upgrading radiation protection infrastructure, to implement the revised version of code of conduct on the safety and security of radioactive sources. Indeed, Morocco expressed its adhesion with the technical assistance project of the IAEA in 2001, carrying on the reinforcement of the national infrastructure of regulation and control of the radioactive materials. The control over radioactive sources is an essential element for maintaining high level of security and safety of radioactive sources. The IAEA T.E.C.-D.O.C.-1388 serves as reference document to implement the control culture. The security problems with which the world is confronted showed that the uses of radioactive sources should subject reinforcements of safety, of control and of security of the radioactive sources. For this purpose, the IAEA launched an action plan for the safety and security of radioactive sources. The IAEA guide Security of radioactive sources will help the

  14. Simulation and analysis on thermodynamic performance of surface water source heat pump system

    Institute of Scientific and Technical Information of China (English)

    Nan Lv; Qing Zhang; Zhenqian Chen; Dongsheng Wu

    2017-01-01

    This work established a thermodynamic performance model of a heat pump system containing a heat pump unit model, an air conditioning cooling and heating load calculation model, a heat exchanger model and a water pump performance model based on mass and energy balances. The thermodynamic performance of a surface water source heat pump air conditioning system was simulated and verified by comparing the simulation results to an actual engineering project. In addition, the effects of the surface water temperature, heat exchanger structure and surface water pipeline transportation system on the thermodynamic performance of the heat pump air conditioning system were analyzed. Under the simulated conditions in this paper with a cooling load of 3400 kW, the results showed that a 1 ℃ decrease in the surface water temperature leads to a 2.3 percent increase in the coefficient of performance; furthermore, an additional 100 m of length for the closed-loop surface water heat exchanger tube leads to a 0.08 percent increase in the coefficient of performance. To decrease the system energy consumption, the optimal working point should be specified according to the surface water transportation length.

  15. Analysis on Dangerous Source of Large Safety Accident in Storage Tank Area

    Science.gov (United States)

    Wang, Tong; Li, Ying; Xie, Tiansheng; Liu, Yu; Zhu, Xueyuan

    2018-01-01

    The difference between a large safety accident and a general accident is that the consequences of a large safety accident are particularly serious. To study the tank area which factors directly or indirectly lead to the occurrence of large-sized safety accidents. According to the three kinds of hazard source theory and the consequence cause analysis of the super safety accident, this paper analyzes the dangerous source of the super safety accident in the tank area from four aspects, such as energy source, large-sized safety accident reason, management missing, environmental impact Based on the analysis of three kinds of hazard sources and environmental analysis to derive the main risk factors and the AHP evaluation model is established, and after rigorous and scientific calculation, the weights of the related factors in four kinds of risk factors and each type of risk factors are obtained. The result of analytic hierarchy process shows that management reasons is the most important one, and then the environmental factors and the direct cause and Energy source. It should be noted that although the direct cause is relatively low overall importance, the direct cause of Failure of emergency measures and Failure of prevention and control facilities in greater weight.

  16. Radiation safety aspects of the LINAC coherent light source

    International Nuclear Information System (INIS)

    Vylet, V.; Fasso, A.; Rokni, S.H.

    1998-01-01

    The radiation protection systems, which comprise the Personnel Protection System (PPS), Beam Containment System (BCS), and shielding, are described. The radiation sources and methods of their assessment are highlighted; these include bremsstrahlung and neutrons from electron beam losses, gas bremsstrahlung, synchrotron radiation, muons, and induced activity. By way of example, a plot of tissue dose as a function of distance from beam axis at the end of the experimental hutch is reproduced. (P.A.)

  17. Sustainable renewable energy seawater desalination using combined-cycle solar and geothermal heat sources

    KAUST Repository

    Missimer, Thomas M.

    2013-01-01

    Key goals in the improvement of desalination technology are to reduce overall energy consumption, make the process "greener," and reduce the cost of the delivered water. Adsorption desalination (AD) is a promising new technology that has great potential to reduce the need for conventional power, to use solely renewable energy sources, and to reduce the overall cost of water treatment. This technology can desalt seawater or water of even higher salinity using waste heat, solar heat, or geothermal heat. An AD system can operate effectively at temperatures ranging from 55 to 80 °C with perhaps an optimal temperature of 80 °C. The generally low temperature requirement for the feedwater allows the system to operate quite efficiently using an alternative energy source, such as solar power. Solar power, particularly in warm dry regions, can generate a consistent water temperature of about 90 °C. Although this temperature is more than adequate to run the system, solar energy collection only can occur during daylight hours, thereby necessitating the use of heat storage during nighttime or very cloudy days. With increasing capacity, the need for extensive thermal storage may be problematic and could add substantial cost to the development of an AD system. However, in many parts of the world, there are subsurface geothermal energy sources that have not been extensively used. Combining a low to moderate geothermal energy recovery system to an AD system would provide a solution to the thermal storage issue. However, geothermal energy development from particularly Hot Dry Rock is limited by the magnitude of the heat flow required for the process and the thermal conductivity of the rock material forming the heat reservoir. Combining solar and geothermal energy using an alternating 12-h cycle would reduce the probability of depleting the heat source within the geothermal reservoir and provide the most effective use of renewable energy. © 2013 Desalination Publications.

  18. Annual performance investigation and economic analysis of heating systems with a compression-assisted air source absorption heat pump

    International Nuclear Information System (INIS)

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

    2015-01-01

    Highlights: • Optimal compression ratio of CASAHP is obtained for the maximum energy saving rate. • Annual performance is improved by 10–20% compared to ASAHP without compression. • Energy saving rate is 17.7–29.2% and investment is reduced to 30–60% for CASAHP. • Both compression and partial-design enhance the economy with given energy saving. • Payback time is reduced from 12–32 to 3–6 years by compression and partial-design. - Abstract: The compression-assisted air source absorption heat pump (CASAHP) is a promising alternative heating system in severe operating conditions. In this research, parameter studies on the annual performance under various compression ratios (CRs) and source temperatures are performed to achieve the maximum energy saving rates (ESRs). Economic analyses of the CASAHP under different CRs and partial-design ratios are conducted to obtain an optimal design that considers both energy savings and economy improvements. The results show that the optimal CR becomes higher in colder regions and with lower heat source temperatures. For a source temperature of 130 °C, the optimal CR values in all of the cities are within 2.0. For source temperatures from 100 to 130 °C, the maximum ESR is in the range of 17.7–29.2% in the studied cities. The efficiency improvement rate (EIR) caused by compression in a severe source condition can reach 10.0–20.0%. From the viewpoint of economy, the relative investment of CASAHP is reduced to 30–60% with a CR of 2.0–3.0. With a 2–6% sacrifice in ESR, the payback period can be reduced from 12–32 to 5–9 years using compression. Partial-design of the CASAHP can further reduce the payback period to 3–6 years with a partial-design ratio of 50% and a CR of 2.8. Additionally, CRs and partial-design ratios are designed comprehensively by seeking the maximum ESR for a given acceptable payback period

  19. Safety assessment of the disposal of sealed radiation sources in boreholes

    International Nuclear Information System (INIS)

    Oliveira, Rosana Lagua de; Vicente, Roberto; Hiromoto, Goro

    2009-01-01

    The Radioactive Waste Management Laboratory (RNML) at the Nuclear Energy Research Institute (NERI) in Sao Paulo, Brazil, is developing the concept of a repository for disused sealed radiation sources in a deep borehole. Several thousands disused sealed radiation sources are stored at NERI awaiting the decision on final disposal and tens of thousands are still under the possession of the licensees. A significant fraction of these sources are long-lived and will require final disposal in a geological repository. The purpose of this paper is to identify and discuss suitable safety assessment strategies for the repository concept and to illustrate a rational approach for a long-term safety assessment methodology. (author)

  20. Power performance of the general-purpose heat source radioisotope thermoelectric generator

    International Nuclear Information System (INIS)

    Bennett, G.L.; Lombardo, J.J.; Rock, B.J.

    1986-01-01

    The General-Purpose Heat Source Radioisotope Thermoelectric Generator (GRHS-RTG) has been developed under the sponsorship of the Department of Energy (DOE) to provide electrical power for the National Aeronautics and Space Administration (NASA) Galileo mission to Jupiter and the joint NASA/European Space Agency (ESA) Ulysses mission to study the polar regions of the sun. A total of five nuclear-heated generators and one electrically heated generator have been built and tested, proving out the design concept and meeting the specification requirements. The GPHS-RTG design is built upon the successful-technology used in the RTGs flown on the two NASA Voyager spacecraft and two US Air Force communications satellites. THe GPHS-RTG converts about 4400 W(t) from the nuclear heat source into at least 285 W(e) at beginning of mission (BOM). The GPHS-RTG consists of two major components: the General-Purpose Heat Source (GPHS) and the Converter. A conceptual drawing of the GPHs-RTG is presented and its design and performance are described

  1. A small-plane heat source method for measuring the thermal conductivities of anisotropic materials

    Science.gov (United States)

    Cheng, Liang; Yue, Kai; Wang, Jun; Zhang, Xinxin

    2017-07-01

    A new small-plane heat source method was proposed in this study to simultaneously measure the in-plane and cross-plane thermal conductivities of anisotropic insulating materials. In this method the size of the heat source element is smaller than the sample size and the boundary condition is thermal insulation due to no heat flux at the edge of the sample during the experiment. A three-dimensional model in a rectangular coordinate system was established to exactly describe the heat transfer process of the measurement system. Using the Laplace transform, variable separation, and Laplace inverse transform methods, the analytical solution of the temperature rise of the sample was derived. The temperature rises calculated by the analytical solution agree well with the results of numerical calculation. The result of the sensitivity analysis shows that the sensitivity coefficients of the estimated thermal conductivities are high and uncorrelated to each other. At room temperature and in a high-temperature environment, experimental measurements of anisotropic silica aerogel were carried out using the traditional one-dimensional plane heat source method and the proposed method, respectively. The results demonstrate that the measurement method developed in this study is effective and feasible for simultaneously obtaining the in-plane and cross-plane thermal conductivities of the anisotropic materials.

  2. Some problems of neutron source multiplication method for site measurement technology in nuclear critical safety

    International Nuclear Information System (INIS)

    Shi Yongqian; Zhu Qingfu; Hu Dingsheng; He Tao; Yao Shigui; Lin Shenghuo

    2004-01-01

    The paper gives experiment theory and experiment method of neutron source multiplication method for site measurement technology in the nuclear critical safety. The measured parameter by source multiplication method actually is a sub-critical with source neutron effective multiplication factor k s , but not the neutron effective multiplication factor k eff . The experiment research has been done on the uranium solution nuclear critical safety experiment assembly. The k s of different sub-criticality is measured by neutron source multiplication experiment method, and k eff of different sub-criticality, the reactivity coefficient of unit solution level, is first measured by period method, and then multiplied by difference of critical solution level and sub-critical solution level and obtained the reactivity of sub-critical solution level. The k eff finally can be extracted from reactivity formula. The effect on the nuclear critical safety and different between k eff and k s are discussed

  3. First in situ operation performance test of ground source heat pump in Tunisia

    International Nuclear Information System (INIS)

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

    2013-01-01

    Highlights: • Evaluate the geothermal energy in Tunisia. • Study of the performance of GSHP system for cooling space. • GSHP is a promising alternative for building cooling in Tunisia. - Abstract: The main purpose of this paper is to study the energetic potential of the deployment in Tunisia of the Ground Source Heat Pump (GSHP) system for cooling mode application. Therefore, a pilot GSHP system using horizontal Ground Heat Exchanger (GHE) was installed and experimented in the Research and Technology Center of Energy (CRTEn), Borj Cédria. The experiment is conducted in a test room with a floor area of about 12 m 2 . In the floor of the tested room is integrated a polyethylene exchanger (PEX) used as a radiant floor cooling (RFC) system. The experimental setup mainly includes the ground temperature, the temperature and flow rate of water circulating in the heat pump and the GHE, as well as the power consumption of the heat pump and circulating pumps. These experimental data are essentially used to evaluate the coefficient of performance of the heat pump (COP hp ) and the overall system (COP sys ) for continuous operation mode. The COP hp and the COP sys were found to be 4.25 and 2.88, respectively. These results reveal that the use of the ground source heat pump is very appropriate for Tunisian building cooling

  4. Induction heating of a spherical aluminum moderator vessel for the Advanced Neutron Source (ANS)

    International Nuclear Information System (INIS)

    Yousuf, A.

    1994-01-01

    This task was to identify and design a heating system to apply 15 kW of heat to a cold source vessel to simulate the Advanced Neutron Source reactor. This research project aims at the analysis of the induction heating of a spherical aluminum moderator vessel. Computer modeling is presented for the design and analysis of the induction heating system. The objective is to apply 15 kW of heat as uniformly as possible to the outer wall of a 410 mm diameter sphere of thickness 1.5 mm. The report also aims at the analysis of a system model which is simulated using the Eddycuff electromagnetic software. The computer model is built with the finite element analysis software Patran. The induction heating system analysis shows that the predicted performance is in close agreement with the computer simulated data. Hardware constraints such as power supplies and matching load are also analyzed in terms of performance and cost. Physical modeling is also suggested, in which the coil and the workpiece are scaled down

  5. Self-optimizing control of air-source heat pump with multivariable extremum seeking

    International Nuclear Information System (INIS)

    Dong, Liujia; Li, Yaoyu; Mu, Baojie; Xiao, Yan

    2015-01-01

    The air-source heat pump (ASHP) is widely adopted for cooling and heating of residential and commercial buildings. The performance of ASHP can be controlled by several operating variables, such as compressor capacity, condenser fan speed, evaporator fan speed and suction superheat. In practice, the system characteristics can be varied significantly by the variations in ambient condition, operation setpoint, internal thermal load and equipment degradation, which makes it difficult to obtain accurate plant models. As consequence, the model based control strategies for ASHP could limit the achievable energy efficiency. Model-free self-optimizing control strategies are thus more preferable. In this study, a multi-input extremum seeking control (ESC) scheme is proposed for both heating and cooling operation of ASHP. The zone temperature is assumed to be regulated by the compressor capacity, while the expansion valve opening is used to regulate the suction superheat at the given setpoint. The total power consumption of the compressor, the condenser fan and the evaporator fan is measured as input to the ESC, while the ESC controls the evaporator fan speed, the condenser fan speed and the suction superheat setpoint. The proposed scheme is evaluated with a Modelica based dynamic simulation model of ASHP under both cooling and heating modes of operation. Simulation results show the effectiveness of the proposed scheme to achieve the maximum achievable efficiency in a nearly model-free manner. - Highlights: • Multi-input ESC. • Air-source heat pump. • Cooling and heating. • Modelica based model

  6. Study on a groundwater source heat pump cooling system in solar greenhouse

    Energy Technology Data Exchange (ETDEWEB)

    Chai, Lilong; Ma, Chengwei [China Agricultural Univ., Beijing (China). Coll. of Water Conservancy and Civil Engineering. Dept. of Agricultural Structure and Bio-environmental Engineering], E-mail: macwbs@cau.edu.cn

    2008-07-01

    This study aims at exploiting the potential of ground source heat pump (GSHP) technology in cooling agricultural greenhouse, and advocating the use of renewable and clean energy in agriculture. GSHP has the multi-function of heating, cooling and dehumidifying, which is one of the fastest growing technologies of renewable energy air conditioning in recent years. The authors carried out experiment on the ground source heat pump system in cooling greenhouse in Beijing region during the summertime of 2007, and conducted analysis on the energy efficiency of the system by using coefficient of performance (COP). According to the data collected during Aug.13-18th, 2007, the coefficient of performance of GSHP system (COP{sub sys}) has reached 3.15 on average during the test. (author)

  7. Exposure calculations for the FRG isotopic heat source project environmental assessment

    International Nuclear Information System (INIS)

    Metcalf, I.L.

    1997-01-01

    The report documents the maximum exposure for transfer of the Federal Republic of Germany (FRG) Isotopic Heat Sources from the 324 Building and placed in interim storage at the Central Waste Complex (CWC). These results are to be reported in the Environmental Assessment DOE-EA- 1 21 1

  8. Dynamic energy converters using an outer heat source for ground uses. Bibliographic study

    International Nuclear Information System (INIS)

    Bousquet, Jean-Louis du

    1969-01-01

    This short bibliographical review presents the main dynamical conversion systems operating with an outer heat source, used for power ranges of a few hundreds Watts to a few hundreds kilowatts and dedicated to ground uses. The study has three parts: recollection of thermodynamic cycles; review of some present or projected realizations; a critical study for selecting converter components (turbine, reciprocating engine, thermodynamical fluid) [fr

  9. Specific power reduction of an ion source due to heating and cathode sputtering of electrodes

    International Nuclear Information System (INIS)

    Hamilton, G.U.; Semashko, N.N.

    The potentialities and limitations of the water-cooled ion-optical system of the ion source designed for continuous operation of the high-power neutral beam injector are determined. The following problems are analyzed: thermal expansion and deformation of electrodes, electrode sputtering as a result of bombardment, and heat transfer to turbulent flow of water

  10. On the mineralization model of 'three sources--heat, water and uranium'

    International Nuclear Information System (INIS)

    Li Xueli

    1992-01-01

    In response to the relations between geological and geothermal settings, geothermal water and uranium mineralizations in the Southeastern China, the model of uranium mineralization in discharge area (depressurization area) of fossil geothermal systems in Mesozoic-Cenozoic Volcanic-magmatic active areas has been put forward and expounded in the view of mineral-formation by the 'three sources'-heat, water and uranium

  11. Savannah River Laboratory isotopic power and heat sources. Monthly report, June 1966

    International Nuclear Information System (INIS)

    1966-06-01

    Progress in research and development is described for the following: preparation of Tm 2 O 3 ; properties of thulium-171; reduction of Pu-236 in Pu-238; 238 Pu oxide with low neutron emission; and encapsulation of cobalt-60 heat sources

  12. Unveiling the sources of disk heating in spiral galaxies with the CALIFA survey

    NARCIS (Netherlands)

    Pinna, F.; Falcón-Barroso, J.; Martig, M.; van de Ven, G.; Lyubenova, M.; Leaman, R.

    The stellar velocity ellipsoid (SVE) quantifies the amount of velocity dispersion in the vertical, radial and azimuthal directions. Since different disk heating mechanisms (e.g. spiral arms, giant molecular clouds, mergers, etc) affect these components differently, the SVE can constrain the sources

  13. Alternative energy sources for the heating and cooling of a building

    CSIR Research Space (South Africa)

    Strydom, JFS

    1979-11-27

    Full Text Available The objective of two of the studies was to choose the most economical source of heating energy, taking cognizance of the building owner’s particular circumstances; in both cases a suitable alternative to light petroleum oil, which had been used...

  14. FRG sealed isotopic heat sources project (C-229) project management plan

    International Nuclear Information System (INIS)

    Metcalf, I.L.

    1997-01-01

    This Project Management Plan defines the cost, scope, schedule, organizational responsibilities, and work breakdown structure for the removal of the Federal Republic of Germany (FRG) Sealed Isotopic Heat Sources from the 324 Building and placed in interim storage at the Central Waste Complex (CWC)

  15. Numerical method of identification of an unknown source term in a heat equation

    Directory of Open Access Journals (Sweden)

    Fatullayev Afet Golayo?lu

    2002-01-01

    Full Text Available A numerical procedure for an inverse problem of identification of an unknown source in a heat equation is presented. Approach of proposed method is to approximate unknown function by polygons linear pieces which are determined consecutively from the solution of minimization problem based on the overspecified data. Numerical examples are presented.

  16. Boundary Layer Fluid Flow in a Channel with Heat Source, Soret ...

    African Journals Online (AJOL)

    The boundary layer fluid flow in a channel with heat source, soret effects and slip condition was studied. The governing equations were solved using perturbation technique. The effects of different parameters such Prandtl number Pr , Hartmann number M, Schmidt number Sc, suction parameter ƒÜ , soret number Sr and the ...

  17. A heat source probe for measuring thermal conductivity in waste rock dumps

    International Nuclear Information System (INIS)

    Blackford, M.G.; Harries, J.R.

    1985-10-01

    The development and use of a heat source probe to measure the thermal conductivity of the material in a waste rock dump is described. The probe releases heat at a constant rate into the surrounding material and the resulting temperature rise is inversely related to the thermal conductivity. The probe was designed for use in holes in the dump which are lined with 50 mm i.d. polyethylene liners. The poor thermal contact between the probe and the liner and the unknown conductivity of the backfill material around the liner necessitated long heating and cooling times (>10 hours) to ensure that the thermal conductivity of the dump material was being measured. Temperature data acquired in the field were analysed by comparing them with temperatures calculated using a two-dimensional cylindrical model of the probe and surrounding material, and the heat transfer code HEATRAN

  18. Optimal operating conditions of a transcritical endoreversible cycle using a low enthalpy heat source

    International Nuclear Information System (INIS)

    Rachedi, Malika; Feidt, Michel; Amirat, Madjid; Merzouk, Mustapha

    2016-01-01

    Highlights: • Thermodynamics analysis of a finite size heat engine driven by a finite heat source. • Mathematical modelling of a transcritical endoreversible organic Rankine cycle. • Parametric study of the optimum operating conditions of transcritical cycle. • Choice of appropriate parameters could lead to very promising efficiencies. - Abstract: In the context of thermodynamic analysis of finite dimensions systems, we studied the optimum operating conditions of an endoreversible thermal machine. In this study, we considered a transcritical cycle, considering external irreversibilities. The hot reservoir is a low enthalpy geothermal heat source; therefore, it is assumed to be finite, whereas the cold reservoir is assumed to be infinite. The power optimisation is investigated by searching the optimum effectiveness of the heat-exchanger at the hot side of the engine. The sum of the total effectiveness and the second law of thermodynamics are used as constraints for optimisation. The optimal temperatures of the working fluid and optimum performances are evaluated based on the most significant parameters of the system: (1) the ratio of heat capacity rate of the working fluid to the heat capacity rate of the coolant and (2) the ratio of the sink temperature to the temperature of the hot source. The parametric study of the cycle and its approximation by a trilateral cycle enabled us to determine the optimum value of the effectiveness of the heat exchangers and the optimal operating temperatures of the cycle considered. The efficiencies obtained are in the range of 15–25% and was found to exceed the efficiency expected by the Curzon and Ahlborn prevision; meanwhile, the Carnot efficiency remains at a high limit.

  19. Optimization and Thermoeconomics Research of a Large Reclaimed Water Source Heat Pump System

    Directory of Open Access Journals (Sweden)

    Zi-ping Zhang

    2013-01-01

    Full Text Available This work describes a large reclaimed water source heat pump system (RWSHPS and elaborates on the composition of the system and its design principles. According to the characteristics of the reclaimed water and taking into account the initial investment, the project is divided into two stages: the first stage adopts distributed heat pump heating system and the second adopts the combination of centralized and decentralized systems. We analyze the heating capacity of the RWSHPS, when the phase II project is completed, the system can provide hydronic heating water with the supply and return water temperature of 55°C/15°C and meet the hydronic heating demand of 8 million square meters of residential buildings. We make a thermal economics analysis by using Thermal Economics theory on RWSHPS and gas boiler system, it is known that the RWSHPS has more advantages, compared with the gas boiler heating system; both its thermal efficiency and economic efficiency are relatively high. It provides a reference for future applications of the RWSHPS.

  20. Heat transfer and friction correlations required to describe steam--water behavior in nuclear safety studies

    International Nuclear Information System (INIS)

    Solbrig, C.W.; McFadden, J.H.; Lyczkowski, R.W.; Hughes, E.D.

    1975-01-01

    The description of two-phase flow is important in nuclear safety studies. Recent two-phase flow descriptions are based upon unequal phase velocities and unequal phase temperatures (UVUT) theories with interphase interaction terms. These theories are more mechanistic than homogeneous theories and require more and different types of correlations than homogeneous theories. The UVUT theories require correlations (or models) which describe wall and interphase mass transfer, friction, momentum transfer, and heat transfer for all flow regimes and heat transfer regimes. A set of correlations is presented in this paper which can be used with UVUT theories. These correlations cover the complete range of parameters needed and in all cases are expected to yield reasonable numbers. (U.S.)

  1. Sensitivity analysis on the performances of a closed-loop Ground Source Heat Pump

    Science.gov (United States)

    Casasso, Alessandro; Sethi, Rajandrea

    2014-05-01

    Ground Source Heat Pumps (GSHP) permit to achieve a significant reduction of greenhouse gas emissions, and the margins for economic saving of this technology are strongly correlated to the long-term sustainability of the exploitation of the heat stored in the soil. The operation of a GSHP over its lifetime should be therefore modelled considering realistic conditions, and a thorough characterization of the physical properties of the soil is essential to avoid large errors of prediction. In this work, a BHE modelling procedure with the finite-element code FEFLOW is presented. Starting from the governing equations of the heat transport in the soil around a GSHP and inside the BHE, the most important parameters are individuated and the adopted program settings are explained. A sensitivity analysis is then carried on both the design parameters of the heat exchanger, in order to understand the margins of improvement of a careful design and installation, and the physical properties of the soil, with the aim of quantifying the uncertainty induced by their variability. The relative importance of each parameter is therefore assessed by comparing the statistical distributions of the fluid temperatures and estimating the energy consumption of the heat pump, and practical conclusions are from these results about the site characterization, the design and the installation of a BHE. References Casasso A., Sethi R., 2014 Efficiency of closed loop geothermal heat pumps: A sensitivity analysis, Renewable Energy 62 (2014), pp. 737-746 Chiasson A.C., Rees S.J., Spitler J.D., 2000, A preliminary assessment of the effects of groundwater flow on closed-loop ground-source heat pump systems, ASHRAE Transactions 106 (2000), pp. 380-393 Delaleux F., Py X., Olives R., Dominguez A., 2012, Enhancement of geothermal borehole heat exchangers performances by improvement of bentonite grouts conductivity, Applied Thermal Engineering 33-34, pp. 92-99 Diao N., Li Q., Fang Z., 2004, Heat transfer in

  2. The heat source of Ruapehu crater lake; deductions from the energy and mass balances

    Science.gov (United States)

    Hurst, A. W.; Bibby, H. M.; Scott, B. J.; McGuinness, M. J.

    1991-05-01

    Regular observations of temperature, outflow rates and water chemistry of Crater Lake, Mt. Ruapehu, New Zealand have been made for the last 25 years. These data have been used to derive a model of the dynamics of the lake, and determine the input of energy, mass, and chloride from the volcano to the Crater Lake. The recent, relatively quiescent state of the volcano, when virtually no heat has been input to the lake, has also enabled an assessment to be made of the surface heat loss characteristics, which play an important role in the model of the lake. The modelling suggests that since about 1982 the ratio of the volcanic heat to mass added to the base of the lake is about 6 MJ/kg, which is not compatible with heating of the lake by magmatic steam alone. Thus, only about 50% of the heating has been by magmatic steam. It is suggested that heat could be transferred from a magmatic source to the region below the lake by a heat-pipe mechanism, commonly associated with geothermal systems. The simultaneous upward movement of vapour phase, and downward movement of liquid phase from condensed vapour allows efficient heat transfer without overall mass transfer. The permeability necessary to supply the required heat is of the order of 10 darcy, and is consistent with a rubble filled vent. For at least the last five years, there has been a characteristic pattern in the Crater Lake temperature record, with alternate heating and cooling phases. The heating phase generally lasts for one or two months, while the cooling phase lasts for six months to a year. A possible explanation for this cyclic behaviour is the presence of a layer of liquid sulphur under Crater Lake, acting as a partial barrier between the heat-pipe and the lake. The unusual variations of the viscosity of liquid sulphur with temperature will mean that at temperatures greater than 160°C, the layer of sulphur becomes highly viscous and would block any upwards steam flow and hence stop the heat input to Crater

  3. Common basis of establishing safety standards and other safety decision-making levels for different sources of health risk

    International Nuclear Information System (INIS)

    Demin, V.F.

    2002-01-01

    Current approaches in establishing safety standards and other decision-making levels for different sources of health risk are critically analysed. To have a common basis for this decision-making a specific risk index R is recommended. In the common sense R is quantitatively defined as LLE caused by the annual exposure to the risk source considered: R = annual exposure, damage (LLE) from the exposure unit. This common definition is also rewritten in specific forms for a set of different risk sources (ionising radiation, chemical pollutants, etc): for different risk sources the exposure can be measured with different quantities (the probability of death, the exposure dose, etc.). R is relative LLE: LLE in years referred to 1 year under the risk. The dimension of this value is [year/year]. In the statistical sense R is conditionally the share of the year, which is lost due to exposure to a risk source during this year. In this sense R can be called as the relative damage. Really lifetime years are lost after the exposure. R can be in some conditional sense considered as a dimensionless quantity. General safety standards R n for the public and occupational workers have been suggested in terms of this index: R n = 0.0007 and 0.01 accordingly. Secondary safety standards are derived for a number of risk sources (ionising radiation, environmental chemical pollutants, etc). Values of R n are chosen in such a way that to have the secondary radiation BSS being equivalent to the current one's. Other general and derived levels for safety decision-making are also proposed including the de-minimus levels. Their possible dependence on the national or regional health-demographic data (HDD) is considered. Such issues as the ways of the integration and averaging of risk indices considered through the national or regional HDD for different risk sources and the use of non-threshold linear exposure - response relationships for ionising radiation and chemical pollutants are analysed

  4. Safety of 5 MW district heating reactor (DHR) and hydraulic dynamic pressure drive control rods

    International Nuclear Information System (INIS)

    Wu Yuanqiang; Wang Dazhong

    1991-11-01

    The principles and movement characteristic of the hydraulic dynamic pressure drive for control rods in 5 MW district heating reactor are described with stress on analysis of its effects on reactor safety features. The drive is different from electric-magnetic drive for PWR or hydraulic drive for BWR. The drive cylinder is driven by dynamic pressure. In the new drive system, the reactor coolant (water) used as actuating medium is pressed by pump, then injected into a step cylinder which is set in the reactor core. The cylinder will move step by step by controlling flow, then the cylinder drives the neutron absorber and controls nuclear reaction. The drive is characterized by simplicity in structure, high reliability, inherent safety, reduction in reactor height, economy, etc

  5. Residual Heat Removal System qualitative probabilistic safety analysis before and after auto closure interlock removal

    International Nuclear Information System (INIS)

    Mikulicic, V.; Simic, Z.

    1992-01-01

    The analysis evaluates the consequences of the removal of the auto closure interlock (ACI) on the Residual Heat Removal System (RHRS) suction/isolation valves at the nuclear power plant. The deletion of the RHRS ACI is in part based on a probabilistic safety analysis (PSA) which justifies the removal based on a criterion of increased availability and reliability. Three different areas to be examined in PSA: the likelihood of an interfacing system LOCA; RHRS availability and reliability; and low temperature overpressurization control. The paper emphasizes particularly the RHRS unavailability and reliability evaluation utilizing the current control circuitry configuration and then with the proposed modification to the control circuitry. (author)

  6. Identifying (subsurface) anthropogenic heat sources that influence temperature in the drinking water distribution system

    Science.gov (United States)

    Agudelo-Vera, Claudia M.; Blokker, Mirjam; de Kater, Henk; Lafort, Rob

    2017-09-01

    The water temperature in the drinking water distribution system and at customers' taps approaches the surrounding soil temperature at a depth of 1 m. Water temperature is an important determinant of water quality. In the Netherlands drinking water is distributed without additional residual disinfectant and the temperature of drinking water at customers' taps is not allowed to exceed 25 °C. In recent decades, the urban (sub)surface has been getting more occupied by various types of infrastructures, and some of these can be heat sources. Only recently have the anthropogenic sources and their influence on the underground been studied on coarse spatial scales. Little is known about the urban shallow underground heat profile on small spatial scales, of the order of 10 m × 10 m. Routine water quality samples at the tap in urban areas have shown up locations - so-called hotspots - in the city, with relatively high soil temperatures - up to 7 °C warmer - compared to the soil temperatures in the surrounding rural areas. Yet the sources and the locations of these hotspots have not been identified. It is expected that with climate change during a warm summer the soil temperature in the hotspots can be above 25 °C. The objective of this paper is to find a method to identify heat sources and urban characteristics that locally influence the soil temperature. The proposed method combines mapping of urban anthropogenic heat sources, retrospective modelling of the soil temperature, analysis of water temperature measurements at the tap, and extensive soil temperature measurements. This approach provided insight into the typical range of the variation of the urban soil temperature, and it is a first step to identifying areas with potential underground heat stress towards thermal underground management in cities.

  7. Sun Safety at Work Canada: a multiple case-study protocol to develop sun safety and heat protection programs and policies for outdoor workers.

    Science.gov (United States)

    Kramer, Desre M; Tenkate, Thomas; Strahlendorf, Peter; Kushner, Rivka; Gardner, Audrey; Holness, D Linn

    2015-07-10

    CAREX Canada has identified solar ultraviolet radiation (UV) as the second most prominent carcinogenic exposure in Canada, and over 75 % of Canadian outdoor workers fall within the highest exposure category. Heat stress also presents an important public health issue, particularly for outdoor workers. The most serious form of heat stress is heat stroke, which can cause irreversible damage to the heart, lungs, kidneys, and liver. Although the need for sun and heat protection has been identified, there is no Canada-wide heat and sun safety program for outdoor workers. Further, no prevention programs have addressed both skin cancer prevention and heat stress in an integrated approach. The aim of this partnered study is to evaluate whether a multi-implementation, multi-evaluation approach can help develop sustainable workplace-specific programs, policies, and procedures to increase the use of UV safety and heat protection. This 2-year study is a theory-driven, multi-site, non-randomized study design with a cross-case analysis of 13 workplaces across four provinces in Canada. The first phase of the study includes the development of workplace-specific programs with the support of the intensive engagement of knowledge brokers. There will be a three-points-in-time evaluation with process and impact components involving the occupational health and safety (OHS) director, management, and workers with the goal of measuring changes in workplace policies, procedures, and practices. It will use mixed methods involving semi-structured key informant interviews, focus groups, surveys, site observations, and UV dosimetry assessment. Using the findings from phase I, in phase 2, a web-based, interactive, intervention planning tool for workplaces will be developed, as will the intensive engagement of intermediaries such as industry decision-makers to link to policymakers about the importance of heat and sun safety for outdoor workers. Solar UV and heat are both health and safety hazards

  8. A general framework to select working fluid and configuration of ORCs for low-to-medium temperature heat sources

    International Nuclear Information System (INIS)

    Vivian, Jacopo; Manente, Giovanni; Lazzaretto, Andrea

    2015-01-01

    Highlights: • General guidelines are proposed to select ORC working fluid and cycle layout. • Distance between critical and heat source temperature for optimal fluid selection. • Separate contributions of cycle efficiency and heat recovery factor. - Abstract: The selection of the most suitable working fluid and cycle configuration for a given heat source is a fundamental step in the search for the optimum design of Organic Rankine Cycles. In this phase cycle efficiency and heat source recovery factor lead to opposite design choices in the achievement of maximum system efficiency and, in turn, maximum power output. In this work, both separate and combined effects of these two performance factors are considered to supply a thorough understanding of the compromise resulting in maximum performance. This goal is pursued by carrying out design optimizations of four different ORC configurations operating with twenty-seven working fluids and recovering heat from sensible heat sources in the temperature range 120–180 °C. Optimum working fluids and thermodynamic parameters are those which simultaneously allow high cycle efficiency and high heat recovery from the heat source to be obtained. General guidelines are suggested to reach this target for any system configuration. The distance between fluid critical temperature and inlet temperature of the heat source is found to play a key role in predicting the optimum performance of all system configurations regardless of the inlet temperature of the heat source

  9. Coupled analysis of passive safety injection and containment filtered venting for passive decay heat removal - 15140

    International Nuclear Information System (INIS)

    Kim, S.H.; Ham, J.H.; Jeong, Y.H.; Chang, S.H.

    2015-01-01

    Lots of interests for the safety of nuclear power plants have risen these days. The safety has to be continuously reviewed and enhanced in nuclear power plants currently operating as well as those designed and constructed in future. After the Fukushima accidents, many additional safety systems which can be applied to nuclear power plants in operation have been proposed. Those include alternating power source such as movable diesel generators and DC batteries in non-safety grade. Also, emergency preparedness for the prevention of a core damage accident was proposed to cope with the extended-SBO (station blackout) by using fire protection systems. In order to prevent the release of radioactive materials, safety systems for preserving the integrity of containment were proposed in two views of cooling and venting containment. Two approaches are effective for mitigating a severe accident. The design concept installing big water tanks besides containment at high level was proposed for various safety functions. One of the functions in the system is to inject the coolant from the elevated tank into a reactor vessel in the case of loss of coolant accident. When the pressure in reactor coolant system is sufficiently low, the coolant can be injected by gravity. If not, the depressurization in reactor vessel would be needed considering the containment pressure. Containment cooling in conventional pressurized water reactors is dependent on containment cooling pumps and sprays. Additional containment cooling systems cannot be simply and easily applied in the current nuclear power plants without major modifications. Therefore, for the operation of passive safety injection system, containment filtered venting system can be adopted for the depressurization of containment. In the design and operation of the passive safety injection system and the containment filtered venting system, main operating points related with open and close pressures in the filtered venting system were

  10. Design and instrumentation of an automotive heat pump system using ambient air, engine coolant and exhaust gas as a heat source

    International Nuclear Information System (INIS)

    Hosoz, M.; Direk, M.; Yigit, K.S.; Canakci, M.; Alptekin, E.; Turkcan, A.

    2009-01-01

    Because the amount of waste heat used for comfort heating of the passenger compartment in motor vehicles decreases continuously as a result of the increasing engine efficiencies originating from recent developments in internal combustion engine technology, it is estimated that heat requirement of the passenger compartment in vehicles using future generation diesel engines will not be met by the waste heat taken from the engine coolant. The automotive heat pump (AHP) system can heat the passenger compartment individually, or it can support the present heating system of the vehicle. The AHP system can also be employed in electric vehicles, which do not have waste heat, as well as vehicles driven by a fuel cell. The authors of this paper observed that such an AHP system using ambient air as a heat source could not meet the heat requirement of the compartment when ambient temperature was extremely low. The reason is the decrease in the amount of heat taken from the ambient air as a result of low evaporating temperatures. Furthermore, the moisture condensed from air freezed on the evaporator surface, thus blocking the air flow through it. This problem can be solved by using the heat of engine coolant or exhaust gases. In this case, the AHP system can have a higher heating capacity and reuse waste heat. (author)

  11. An assessment of dynamic energy conversion systems for terrestrial radioisotope heat sources

    International Nuclear Information System (INIS)

    Thayer, G.R.

    1985-01-01

    The use of dynamic conversion systems to convert to electricity the heat generated in a 7500 W(t) 90 Sr radioisotopic heat source is examined. Brayton Cycle, three Organic Rankine systems (Barber-Nichols/ORMAT, Sundstrand, and TRW concepts), Organic Rankine plus thermoelectrics, and Stirling Engine systems were studied. The systems were ranked for a North Warning System mission using a Los Alamos Multi-Attribute Decision Theory code. Three different heat source designs were used: Case I with a beginning of life (BOL) source temperature of 640 0 C, Case II with a BOL source temperature of 745 0 C, and Case III with a BOL source temperature of 945 0 C. The Stirling Engine system was the top-ranked system for Cases I and II, closely followed by the ORC systems in Case I and ORC and thermoelectrics in Case II. The Brayton-Cycle system was top-ranked for Case III, with the Stirling Engine system a close second

  12. Quantification of exploitable shallow geothermal energy by using Borehole Heat Exchanger coupled Ground Source Heat Pump systems

    International Nuclear Information System (INIS)

    Hein, Philipp; Zhu, Ke; Bucher, Anke; Kolditz, Olaf; Pang, Zhonghe; Shao, Haibing

    2016-01-01

    Highlights: • The amount of technically exploitable shallow geothermal energy was quantified. • Therefore, a comprehensive numerical borehole heat exchanger model was employed. • The concept of equivalent temperature drop is introduced. • For one BHE, an equivalent temperature drop of 1.8–2.8 °C over 30 years is realistic • The average extractable energy amount evaluates to be 3.5–5.4 kW h m"−"2 a"−"1. - Abstract: In previous studies, the amount of exploitable shallow geothermal energy was estimated by assuming a uniform temperature drop of 2–6 °C in the aquifer. In this work, a more comprehensive numerical model has been employed to evaluate the available amount of shallow geothermal energy by using Borehole Heat Exchanger coupled Ground Source Heat Pump systems. Numerical experiments have been performed by simulating the long-term evolution of the subsurface temperature field, which is subject to the operation of borehole heat exchangers and varying parameters like subsurface thermal conductivity and groundwater flow velocity. The concept of equivalent temperature drop is proposed as an auxiliary quantity for the subsurface. With the help of this parameter, a procedure has been established to quantify the amount of shallow geothermal potential. Following this approach, a realistic equivalent temperature reduction is found to be from −1.8 to −4.4 °C in the subsurface over a period of 30 years. This can be translated to an annual extractable geothermal energy value in a unit surface area, and it ranges from 3.5 to 8.6 kW h m"−"2 a"−"1. The exact value is site specific and heavily depends on the soil thermal conductivity, groundwater velocity, and borehole arrangement.

  13. Optimal Design of ORC Systems with a Low-Temperature Heat Source

    Directory of Open Access Journals (Sweden)

    Nicolas Galanis

    2012-02-01

    Full Text Available A numerical model of subcritical and trans-critical power cycles using a fixed-flowrate low-temperature heat source has been validated and used to calculate the combinations of the maximum cycle pressure (Pev and the difference between the source temperature and the maximum working fluid temperature (DT which maximize the thermal efficiency (ηth or minimize the non-dimensional exergy losses (β, the total thermal conductance of the heat exchangers (UAt and the turbine size (SP. Optimum combinations of Pev and DT were calculated for each one of these four objective functions for two working fluids (R134a, R141b, three source temperatures and three values of the non-dimensional power output. The ratio of UAt over the net power output (which is a first approximation of the initial cost per kW shows that R141b is the better working fluid for the conditions under study.

  14. Safety of radiation sources and security of radioactive materials. A Romanian approach

    International Nuclear Information System (INIS)

    Ghilea, S.; Coroianu, A.I.; Rodna, A.L.

    2001-01-01

    After a brief explanation on the scope of applications of nuclear energy and practices with ionizing radiation in Romania, the report explains the current national infrastructure for radiation safety making reference in particular to the National Commission for Nuclear Activities Control as the regulatory authority for the safety of radiation sources. The report also describes the existing legal framework, provides information on the list of normative acts in force, and on the system of authorization, inspection and enforcement, which operates effectively. (author)

  15. ELECTROMAGNETIC SAFETY OF ELECTRIC TRANSPORT SYSTEMS: MAIN SOURCES AND PARAMETERS OF MAGNETIC FIELDS

    Directory of Open Access Journals (Sweden)

    N. G. Ptitsyna

    2013-03-01

    Full Text Available Magnetic fields produced by electric drive vehicles may break electromagnetic safety. For electromagnetic safety and electromagnetic compatibility knowledge about characteristics and sources of magnetic fields in the electric transport is necessary. The article deals with analysis of available data about magnetic fields in electric cars and comparison with results of our measurements carried out in the other types of electrified transport systems.

  16. IMPACT OF GEOTHERMAL GRADIENT ON GROUND SOURCE HEAT PUMP SYSTEM MODELING

    Directory of Open Access Journals (Sweden)

    Tomislav Kurevija

    2014-07-01

    Full Text Available ndisturbed ground temperature is one of the most crucial thermogeological parameters needed for shallow geothermal resources assessment. Energy considered to be geothermal is energy stored in the ground at depths where solar radiation has no effect. At depth where undisturbed ground temperature occurs there is no influence of seasonal variations in air temperature from surface. Exact temperature value, and depth where it occurs, is functionally dependent on surface climate parameters and thermogeologic properties of ground. After abovementioned depth, increase of ground temperature is solely dependent on geothermal gradient. Accurately determined value of undisturbed ground temperature is beneficial for proper sizing of borehole heat exchangers. On practical example of building which is being heated and cooled with shallow geothermal resource, influences of undisturbed ground temperature and geothermal gradient, on size of borehole heat exchanger are going to be presented. Sizing of borehole heat exchanger was calculated with commercial software Ground Loop Designer (GLD, which uses modified line source and cylinder source solutions of heat conduction in solids.

  17. Regulatory Oversight of Radioactive Sources through the Integrated Management of Safety and Security

    International Nuclear Information System (INIS)

    Horvath, K.

    2016-01-01

    The Hungarian Atomic Energy Authority (HAEA) has full regulatory competence; its mission is to oversee the safety and security of all the peaceful applications of atomic energy. All the radioactive sources having activity above the exemption level is registered and licensed both from safety and security points of view. The Hungarian central register of radioactive sources contains about 7,000 radioactive sources and 450 license holders. In order to use its limited resources the HAEA has decided to introduce an integrated regulatory oversight programme. Accordingly, during the licensing process and inspection activities the HAEA intends to assess both safety and security aspects at the same time. The article describes the Hungarian the various applications of radioactive materials, and summarizes the preparation activities of the HAEA. (author)

  18. Safety of Pseudomonas chlororaphis as a gene source for genetically modified crops.

    Science.gov (United States)

    Anderson, Jennifer A; Staley, Jamie; Challender, Mary; Heuton, Jamie

    2018-02-01

    Genetically modified crops undergo extensive evaluation to characterize their food, feed and environmental safety prior to commercial introduction, using a well-established, science-based assessment framework. One component of the safety assessment includes an evaluation of each introduced trait, including its source organism, for potential adverse pathogenic, toxic and allergenic effects. Several Pseudomonas species have a history of safe use in agriculture and certain species represent a source of genes with insecticidal properties. The ipd072Aa gene from P. chlororaphis encodes the IPD072Aa protein, which confers protection against certain coleopteran pests when expressed in maize plants. P. chlororaphis is ubiquitous in the environment, lacks known toxic or allergenic properties, and has a history of safe use in agriculture and in food and feed crops. This information supports, in part, the safety assessment of potential traits, such as IPD072Aa, that are derived from this source organism.

  19. ITER Safety Task NID-5A, Subtask 1-1: Source terms and energies - initial tritium source terms. Final report

    International Nuclear Information System (INIS)

    Fong, C.; Kalyanam, K.M.; Tanaka, M.R.; Sood, S.; Natalizio, A.; Delisle, M.

    1995-02-01

    The overall objective of the Early Safety and Environmental Characterization Study (ESECS) is to assess the environmental impact of tritium using appropriate assumptions on a hypothetical site for ITER, having the r eference s ite characteristics as proposed by the JCT. The objective of this work under the above subtask 1-1, NID-5a, is to determine environmental source terms (i.e., process source term x containment release fraction) for the fuel cycle and cooling systems. The work is based on inventories and process source terms (i.e., inventory x mobilization fraction), provided by others (under Task NID 3b). The results of this work form the basis for the determination, by others, of the off-site dose (i.e., environmental source term x dose/release ratio). For the determination of the environmental source terms, the TMAP4 code has been utilized (ref 1). This code is approved by ITER for safety assessment. Volume 3 is a compilation of appendices giving detailed results of the study

  20. ITER Safety Task NID-5A, Subtask 1-1: Source terms and energies - initial tritium source terms. Final report

    International Nuclear Information System (INIS)

    Fong, C.; Kalyanam, K.M.; Tanaka, M.R.; Sood, S.; Natalizio, A.; Delisle, M.

    1995-02-01

    The overall objective of the Early Safety and Environmental Characterization Study (ESECS) is to assess the environmental impact of tritium using appropriate assumptions on a hypothetical site for ITER, having the r eference s ite characteristics as proposed by the JCT. The objective of this work under the above subtask 1-1, NID-5a, is to determine environmental source terms (i.e., process source term x containment release fraction) for the fuel cycle and cooling systems. The work is based on inventories and process source terms (i.e., inventory x mobilization fraction), provided by others (under Task NID 3b). The results of this work form the basis for the determination, by others, of the off-site dose (i.e., environmental source term x dose/release ratio). For the determination of the environmental source terms, the TMAP4 code has been utilized (ref 1). This code is approved by ITER for safety assessment. Volume 2 is a compilation of appendices giving detailed results of the study. 5 figs

  1. Performance analysis of low temperature heat source of organic Rankine cycle for geothermal application

    Science.gov (United States)

    Pintoro, A.; Ambarita, H.; Nur, T. B.; Napitupulu, F. H.

    2018-02-01

    Indonesia has a high potential energy resources from geothermal activities. Base on the report of Asian Development Bank and World Bank, the estimated of Indonesian hydrothermal geothermal resource considered to be the largest among the world. If it’s can be utilized to produce the electric power, it’s can contribute to increasing the electrification rates in Indonesia. In this study, an experimental studied of electric power generation, utilizing the Organic Rankine Cycle (ORC) system to convert the low level heat of hydrothermal as an energy source. The temperature of hydrothermal was modelled as hot water from water boiler which has a temperature range from 60 °C - 100 °C to heat up the organic working fluid of ORC system. The system can generated 1,337.7 watts of electricity when operated using R134A with hot water inlet temperature of 100 °C. Changing system working fluid to R245fa, the net power obtained increase to 1,908.9 watts with the same heat source condition. This study showed that the ORC system can be implemented to utilize low temperature heat source of hydrothermal in Indonesia.

  2. Effects of the generator and evaporator temperature differences on a double absorption heat transformer—Different control strategies on utilizing heat sources

    International Nuclear Information System (INIS)

    Wang, Hanzhi; Li, Huashan; Bu, Xianbiao; Wang, Lingbao

    2017-01-01

    Highlights: • Effects of the GETD on the DAHT system performance are analyzed. • Three different configurations are compared in detail. • Suggestions on the heat source control strategies are given. - Abstract: The combination of the absorption heat transformer with renewable energy systems, like solar thermal systems, is raising more and more concern. In those combined systems the strategies on utilizing heat sources can affect system thermodynamic performance significantly. Therefore, this study presents a detailed analysis on the effect of the heat source temperature and different heat source flow patterns on the performance of a double absorption heat transformer (DAHT). A detailed comparative study is carried out to clarify the impact of the generator and evaporator temperature differences (GETD) on the coefficient of performance (COP), exergy efficient (ECOP), exergy destruction rates in the individual components and heat transfer areas needed for each component. The results show that the generator, condenser and absorber-evaporator are responsible for most of the exergy destruction rate in the DAHT system; the parallel-flow configuration (the generator temperature is equal to the evaporator temperature) performs better under the high gross temperature lift conditions; in the case of the counter-flow configuration (the generator temperature is relatively higher), better performance can be obtained in both the COP and ECOP under the proper heat source temperature (85 and 95 °C); the fair-flow configuration (higher temperature in the evaporator) is not recommended in this paper due to no advantages found in either thermodynamic performance or system size.

  3. Engineering for high heat loads on ALS [Advanced Light Source] beamlines

    International Nuclear Information System (INIS)

    DiGennaro, R.; Swain, T.

    1989-08-01

    This paper discussed general thermal engineering problems and specific categories of thermal design issues for high photon flux beam lines at the LBL Advanced Light Source: thermal distortion of optical surfaces and elevated temperatures of thermal absorbers receiving synchrotron radiation. A generic design for water-cooled heat absorbers is described for use with ALS photon shutters, beam defining apertures, and heat absorbing masks. Also, results of in- situ measurements of thermal distortion of a water-cooled mirror in a synchrotron radiation beam line are compared with calculated performance estimates. 17 refs., 2 figs

  4. Heat sources for bright-rimmed molecular clouds: CO observations of NGC 7822

    International Nuclear Information System (INIS)

    Elmegreen, B.G.; Dickinson, D.F.; Lada, C.J.

    1978-01-01

    Observations of the 2.6 mm carbon monoxide line in the bright rim NGC 7822 reveal that the peak excitation and column density of the molecule lie in a ridge ahead of the ionization front. Several possibilities for the excitation of this ridge are discussed. Cosmic rays are shown to provide an excellent heat source for Bok globules, but they can account for only approx.20% of the required heating in NGC 7822. Direct shock or compressional heating of the gas could be adequate only if the pressure inside the cloud is much larger than the thermal pressure. If, in fact, this internal pressure is determined by the source of line broadening (e.g., magnetic fields or turbulence), then shock or compressional heating could be important, and pressure equilibrium may exist between the neutral cloud and the bright rim. Heating by warm grains or by the photoelectric effect is also considered, but such mechanisms are probably not important if the only source of radiation is external to the cloud. This is primarily a result of the low cloud density (approx.10 3 cm -3 ) inferred from our observations. The extent to which unknown embedded stars may provide the required gaseous heating cannot be estimated from our observations of NGC 7822.An interesting and new heat source is suggested which may have important applications to bright-rimmed clouds or to any other predominantly neutral clouds that may have undergone some recent compression. We suggest that the heat input to neutral gas due to the relaxation of internal magnetic fields will be greatly enhanced during cloud compression (with or without a shock). We show that the power input to the gas will increase more with increasing density than will the cooling rate. As a result, cloud compression can lead to an increase in the gas temperature for a period lasting several million years, which is the decay time of the compressed field. The observed ridge in NGC 7822 may be due to stimulated release of internal magnetic energy

  5. A Green's function solution for a rectangular heat source on an infinite plate

    International Nuclear Information System (INIS)

    Bainbridge, B.L.

    1989-01-01

    The applications associated with a rectangular heat source on an infinite plate range from integrated circuits to thin film heat flux sensors on thin substrates. The particular problem from which the solution is developed concerns the use of a resistive strip for monitoring currents generated in circuits exposed to electromagnetic fields. The Green's function formulation is solved by using early and late time approximations for which analytical solutions can be derived. In this paper expressions are developed for three sets of boundary conditions and compared to the experimental performance of a physical device

  6. Processing summary report: Fabrication of cesium and strontium heat and radiation sources

    International Nuclear Information System (INIS)

    Holton, L.K. Jr.; Surma, J.E.; Allen, R.P.

    1989-02-01

    The Pacific Northwest Laboratory (PNL), has produced 30 isotopic heat sources (canisters) for the Federal Republic of Germany (FRG) to be used as part of a repository testing program in the Asse Salt Mine. PNL program work involved the filling, closure, and decontamination of the 30 canisters. The canisters were fabricated (filled) in three separate processing campaigns using the radioactive liquid-fed ceramic melter to produce a borosilicate glass. Within the borosilicate glass matrix radiochemical constituents ( 137 Cs and 90 Sr) were immobilized to yield a product with a predetermined decay heat and surface radiation exposure rate

  7. 太阳能辅助地源热泵供暖实验研究%Experimental study of a solar assisted ground source heat pump for heating

    Institute of Scientific and Technical Information of China (English)

    赵忠超; 丰威仙; 巩学梅; 米浩君; 成华; 云龙

    2014-01-01

    An experimental study is performed to determine the performance of the solar assisted ground source heat pump(SAGSHP)by using a solar-ground source heat pump hybrid system in the city of Ningbo. The result shows that comparing with the ground source heat pump(GSHP),when the ratio of solar energy to the whole en-ergy is 41. 9% ,the coefficient of performance( COP)of the heat pump and system can improve 15. 1% and 7. 7% respectively. Therefore,the solar assisted ground source heat pump has a significant performance advan-tage according to the experimental result.%选取宁波某公用建筑的太阳能-地源热泵复合系统为实验系统,对太阳能辅助地源热泵( solar assisted ground source heat pump,SAGSHP)供暖进行了实验研究.研究结果表明:与单一的地源热泵(ground source heat pump,GSHP)相比,当太阳能承担41.9%负荷时,热泵机组和整个系统的能效比(coefficient of performance,COP)分别提高了15.1%和7.7%, SAGSHP 供暖运行模式具有明显的性能优势.

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

    Directory of Open Access Journals (Sweden)

    Parham Eslami-Nejad

    2018-02-01

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

  9. A study on the mechanical stress relieving and safety assessment without post-weld heat treatment

    International Nuclear Information System (INIS)

    Xu Jijin; Chen Ligong; Ni Chunzhen

    2007-01-01

    For full welded body valve, the temperature of grommet cannot exceed 150 deg. C in order to prevent it from damaging and assure the tightness and the service life of valve. Therefore, post-weld heat treatment (PWHT) cannot be used to relieve the residual stresses. In this study, the effect of the mechanical stress relieving (MSR) treatment on the residual stresses was studied by the finite element method and experimental work. A pressure and time diagram of MSR treatment was established. A two-dimensional axisymmetric finite element model was used to simulate the residual stresses field. Before and after MSR treatment, the residual stresses on the outer surface were measured by the blind hole drilling method. Finally, the fracture toughness behaviors of weld zone (WZ) and heat affected zone (HAZ) were investigated in terms of crack tip opening displacement (CTOD) according to BS7448 and DNV-OS-C401 fracture toughness tests standards. The safety of the valve in active service was assessed without PWHT. Through comparison and analysis, the axial residual stresses and the hoop residual stresses on the outer surface of valve are mainly tensile. The peak value of tensile stress occurs nearer to the outer surface of the valve. MSR treatment can decrease the peak value of axial residual stresses and hoop residual stresses on the outer surface obviously and make the residual stresses distribution more uniform. The safety of the valve in active service is reliable without PWHT

  10. Safety issues in the handling of radiation sources in category IV gamma radiation facilities

    International Nuclear Information System (INIS)

    Kohli, A.K.

    2002-01-01

    There is potential for incidents/accidents related to handling of radiation sources. This is increasing due to the fact that more number of plants that too with much larger levels of activity are now coming up. Such facilities produce very high levels of exposure rates during irradiation. A person accidentally present in the irradiation cell can receive a lethal dose within a very short time. Apart from safety requirements during operation and maintenance of these facilities, safety during loading and unloading of sources is important. Category IV type irradiators are the most common. Doubly encapsulated Co-60 slugs are employed to form the source pencils. These irradiators employ a water pool for safely storing the source pencils when irradiation of the products is not going on or when human access is needed into the irradiation cell for some maintenance or source loading/unloading operations. Safety during loading/unloading operations of source pencils is important. In design itself care needs to be taken such that all such operations are convenient and any incident will not lead to a situation where it becomes difficult to come out. Different situations, which can arise during handling of radiation sources and suggested designs to obviate such tight situations, are discussed. (Author)

  11. Ultraviolet light and heat source selection in captive spiny-tailed iguanas (Oplurus cuvieri)

    International Nuclear Information System (INIS)

    Dickinson, H.C.; Fa, J.E.

    1997-01-01

    Three experimental manipulations were conducted to assess the influence of heat source selection and active thermoregulation on ultraviolet (UV) light exposure in captive spiny-tailed iguanas (Oplurus cuvieri) at the Jersey Wildlife Preservation Trust. Four replicates per manipulation were conducted on six individual lizards. All animals were tested in a separate enclosure to which they were acclimated before observations. Data on choice of thermal sources were collected during the first 2 hr of light, when lizards were actively thermoregulating. Animals were allowed to choose between incandescent light, UV light and a non-light heat source (thermotube) in different combinations. Recorded temperatures close to the incandescent light (37°C) were always significantly higher than at the thermotube (33°C) and at the UV light (29°C). Manipulation 1 offered the animals a choice of an UV light and an incandescent light as thermal sources. Manipulation 2 presented animals with the thermal choices in Manipulation 1, but substrates under each source in Manipulation 1 were switched. In Manipulation 3, animals could choose between an incandescent light and the thermotube. All studied lizards were significantly more attracted to the incandescent light than to the UV light or thermotube. Incandescent light elicited a significantly higher proportion of basking behaviors in all individuals than the other sources. A high proportion of time basking was also spent in front of the thermotube but fewer individuals and less time were spent basking under the UV light. Heat source selection was generally found to be independent of substrate. Management applications of this preference are suggested for juvenile diurnal heliothermic iguanids. (author)

  12. Safety and security of radioactive sources in industrial radiography in Bangladesh

    Energy Technology Data Exchange (ETDEWEB)

    Mollah, A. S.; Nazrul, M. Abdullah [Industrial Inspection Service Limited, Dhaka (Bangladesh)

    2013-07-01

    Malicious use of radioactive sources can involve dispersal of that material through an explosive device. There has been recognition of the threat posed by the potential malicious misuse of NDT radioactive source by terrorists. The dispersal of radioactive material using conventional explosives, referred to as a 'dirty bomb', could create considerable panic, disruption and area access denial in an urban environment. However, as it is still a relatively new topic among regulators, users, and transport and storage operators worldwide, international assistance and cooperation in developing the necessary regulatory and security infrastructure is required. The most important action in reducing the risk of radiological terrorism is to increase the security of radioactive sources. This paper presents safety and security considerations for the transport and site storage of the industrial radiography sources as per national regulations entitled 'Nuclear Safety and Radiation Control Rules-1997'.The main emphasis was put on the stages of some safety and security actions in order to prevent theft, sabotage or other malicious acts during the transport of the packages. As a conclusion it must be mentioned that both safety and security considerations are very important aspects that must be taking in account for the transport and site storage of radioactive sources used in the practice of industrial radiography. (authors)

  13. Safety and security of radiation sources and radioactive materials: A case of Zambia - least developed country

    International Nuclear Information System (INIS)

    Banda, S.C.

    1998-01-01

    In Zambia, which is current (1998) classified as a Least Developed Country has applications of nuclear science and technology that cover the medical, industrial, education and research. However, the application is mainly in medical and industry. Through the responsibility of radiation source is within the mandate of the Radiation Protection Board. The aspects involving security fall on different stake holders some that have no technical knowledge on what radiation is about. The stake holders in this category include customs clearing and forwarding agents, state security/defence agencies and the operators. Such a situation demands a national system that should be instituted to meet the safety and security requirements but takes into account the involvement of the diverse stake holders. In addition such system should avoid unnecessary exposure, ensure safety of radioactive materials and sources, detect illicit trade and maintain integrity of such materials or sources. This paper will provide the status on issue in Zambia and the challenges that exist to ensure further development in application of Nuclear Science and Technology (S and T) in the country takes into account the safety and security requirements that avoid deliberate and accidental loss of radiation sources and radioactive materials. The Government has a responsibility to ensure that effective system is established and operated to protect radiation sources and radioactive materials from theft, sabotage and ensure safety. (author)

  14. Safety and security of radioactive sources in industrial radiography in Bangladesh

    International Nuclear Information System (INIS)

    Mollah, A. S.; Nazrul, M. Abdullah

    2013-01-01

    Malicious use of radioactive sources can involve dispersal of that material through an explosive device. There has been recognition of the threat posed by the potential malicious misuse of NDT radioactive source by terrorists. The dispersal of radioactive material using conventional explosives, referred to as a 'dirty bomb', could create considerable panic, disruption and area access denial in an urban environment. However, as it is still a relatively new topic among regulators, users, and transport and storage operators worldwide, international assistance and cooperation in developing the necessary regulatory and security infrastructure is required. The most important action in reducing the risk of radiological terrorism is to increase the security of radioactive sources. This paper presents safety and security considerations for the transport and site storage of the industrial radiography sources as per national regulations entitled 'Nuclear Safety and Radiation Control Rules-1997'.The main emphasis was put on the stages of some safety and security actions in order to prevent theft, sabotage or other malicious acts during the transport of the packages. As a conclusion it must be mentioned that both safety and security considerations are very important aspects that must be taking in account for the transport and site storage of radioactive sources used in the practice of industrial radiography. (authors)

  15. Ground source heat pumps versus high efficiency natural gas furnaces in Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, J.

    2003-02-02

    For the past twenty years or so, the heating and cooling of numerous buildings in northern Europe has been accomplished using ground source heat pumps (GSHPs), while in North America they have been in use for approximately ten years. In the Prairies, natural gas furnaces dominate, while GSHP are more popular in eastern Canada. The author noted that natural gas furnaces have an efficiency of 80 per cent or less, while high efficiency natural gas (HENG) furnaces, more expensive, have an efficiency in the 90 per cent range. A brief outline of the principles behind GSHPs was provided. The Coefficient of Performance (COP) of GSHP reaches up to 500 per cent depending whether the unit is cooling or heating. The amount of heat produced by a heating system expressed as a percentage of the energy input required to operate the system is the definition used for the efficiency. In those cases where it is possible to amortize the initial costs, pay now or obtain a subsidy, the installation of GSHP is advantageous. Several factors affect the total cost of heating a building, such as the airtightness of the building and its insulation, the coldness of the climate, and the inside controlled temperature setting. The author then examined the cost of operating a GSHP versus a natural gas furnace. In most examples studied, the cost of operating a GSHP was less than the cost of operating a natural gas furnace. The Total Equivalent Warming Impact (TEWI) of GSHPs and HENG furnaces was examined. The author concluded that the cost of heating by GSHP in Alberta will be lower than the cost of heating by HENG which requires a separate air conditioning unit for the summer months, with additional improvements in efficiency and insulation. 7 refs., 4 tabs.

  16. A simulation-based analysis of variable flow pumping in ground source heat pump systems with different types of borehole heat exchangers: A case study

    International Nuclear Information System (INIS)

    Zarrella, Angelo; Emmi, Giuseppe; De Carli, Michele

    2017-01-01

    Highlights: • The work focuses on the variable flow in ground source heat pump systems. • The constant and variable speed circulation pumps in the ground loop are compared. • The constant temperature difference control across the heat pump is studied. • The variable flow affects the energy performance of the heat pump. • The constant temperature difference control offers an attractive energy saving. - Abstract: A simulation model of ground source heat pump systems has been used to investigate to what extent a variable flow of the heat-carrier fluid of the ground loop affects the energy efficiency of the entire system. The model contemporaneously considers the borehole heat exchangers, the heat pump, the building load, and the control strategies for the circulation pumps of the ground loop. A constant speed of the circulation pumps of the ground loop was compared with a variable flow controlled by means of a constant temperature difference across the heat pump on the ground side considering the load profile of an office building located in North Italy. The analysis was carried out for a single U-tube, double U-tube and coaxial pipe heat exchangers. The control strategies adopted to manage the flow rate of the heat-carrier fluid of the ground loop affect both the heat exchange rate of the borehole field and the heat pump’s long-term energy efficiency. The simulations show considerable differences in the system’s seasonal energy efficiency. The constant speed of the circulation pumps leads to the best results as far as the heat pump’s energy performance was concerned, but this advantage was lost because of the greater amount of electrical energy used by the circulation pumps; this, of course, affects the energy efficiency of the entire system. The optimal solution appears then to be a constant temperature difference in the heat-carrier fluid across the heat pump.

  17. Code of conduct on the safety and security of radioactive sources

    International Nuclear Information System (INIS)

    2004-01-01

    The objectives of the Code of Conduct are, through the development, harmonization and implementation of national policies, laws and regulations, and through the fostering of international co-operation, to: (i) achieve and maintain a high level of safety and security of radioactive sources; (ii) prevent unauthorized access or damage to, and loss, theft or unauthorized transfer of, radioactive sources, so as to reduce the likelihood of accidental harmful exposure to such sources or the malicious use of such sources to cause harm to individuals, society or the environment; and (iii) mitigate or minimize the radiological consequences of any accident or malicious act involving a radioactive source. These objectives should be achieved through the establishment of an adequate system of regulatory control of radioactive sources, applicable from the stage of initial production to their final disposal, and a system for the restoration of such control if it has been lost. This Code relies on existing international standards relating to nuclear, radiation, radioactive waste and transport safety and to the control of radioactive sources. It is intended to complement existing international standards in these areas. The Code of Conduct serves as guidance in general issues, legislation and regulations, regulatory bodies as well as import and export of radioactive sources. A list of radioactive sources covered by the code is provided which includes activities corresponding to thresholds of categories

  18. Regional cooperation to reduce the safety and security risks of Orphan radioactive sources

    International Nuclear Information System (INIS)

    Howard, Geoffrey; Hacker, Celia; Murray, Allan; Romallosa, Kristine; Caseria, Estrella; Africa del Castillo, Lorena

    2008-01-01

    ANSTO's Regional Security of Radioactive Sources (RSRS) Project, in cooperation with the Philippine Nuclear Research Institute (PNRI), has initiated a program to reduce the safety and security risks of orphan radioactive sources in the Philippines. Collaborative work commenced in February 2006 during the Regional Orphan Source Search and Methods Workshop, co-hosted by ANSTO and the US National Nuclear Security Administration. Further professional development activities have occurred following requests by PNRI to ANSTO to support improvements in PNRI's capability and training programs to use a range of radiation survey equipment and on the planning and methods for conducting orphan source searches. The activities, methods and outcomes of the PNRI-ANSTO cooperative program are described, including: i.) Delivering a training workshop which incorporates use of source search and nuclide identification equipment and search methodology; and train-the-trainer techniques for effective development and delivery of custom designed training in the Philippines; ii.) Support and peer review of course work on Orphan Source Search Equipment and Methodology developed by PNRI Fellows; iii.) Supporting the delivery of the inaugural National Training Workshop on Orphan Source Search hosted by PNRI in the Philippines; iv.) Partnering in searching for orphan sources in Luzon, Philippines, in May 2007. The methods employed during these international cooperation activities are establishing a new model of regional engagement that emphasises sustainability of outcomes for safety and security of radioactive sources. (author)

  19. Code of conduct on the safety and security of radioactive sources

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-01-01

    The objectives of the Code of Conduct are, through the development, harmonization and implementation of national policies, laws and regulations, and through the fostering of international co-operation, to: (i) achieve and maintain a high level of safety and security of radioactive sources; (ii) prevent unauthorized access or damage to, and loss, theft or unauthorized transfer of, radioactive sources, so as to reduce the likelihood of accidental harmful exposure to such sources or the malicious use of such sources to cause harm to individuals, society or the environment; and (iii) mitigate or minimize the radiological consequences of any accident or malicious act involving a radioactive source. These objectives should be achieved through the establishment of an adequate system of regulatory control of radioactive sources, applicable from the stage of initial production to their final disposal, and a system for the restoration of such control if it has been lost. This Code relies on existing international standards relating to nuclear, radiation, radioactive waste and transport safety and to the control of radioactive sources. It is intended to complement existing international standards in these areas. The Code of Conduct serves as guidance in general issues, legislation and regulations, regulatory bodies as well as import and export of radioactive sources. A list of radioactive sources covered by the code is provided which includes activities corresponding to thresholds of categories.

  20. Environmental considerations for geothermal energy as a source for district heating

    International Nuclear Information System (INIS)

    Rafferty, K.D.

    1996-01-01

    Geothermal energy currently provides a stable and environmentally attractive heat source for approximately 20 district heating (DH) systems in the US. The use of this resource eliminates nearly 100% of the conventional fuel consumption (and, hence, the emissions) of the loads served by these systems. As a result, geothermal DH systems can rightfully claim the title of the most fuel-efficient DH systems in operation today. The cost of producing heat from a geothermal resource (including capitalization of the production facility and cost for pumping) amounts to an average of $1.00 per million Btu (0.0034 $/kWh). The major environmental challenge for geothermal systems is proper management of the producing aquifer. Many systems are moving toward injection of the geothermal fluids to ensure long-term production