WorldWideScience

Sample records for radioactive heat generation

  1. Ocean disposal of heat generating radioactive waste

    International Nuclear Information System (INIS)

    1986-03-01

    The objective of this study was to predict tensile stress levels in thin-walled titanium alloy and thick-walled carbon steel containers designed for the ocean disposal of heat-generating radioactive wastes. Results showed that tensile stresses would be produced in both designs by the expansion of the lead filter, for a temperature rise of 200 0 C. Tensile stress could be reduced if the waste heat output at disposal was reduced. Initial stresses for the titanium-alloy containers could be relieved by heat treatment. (UK)

  2. Ocean disposal of heat generating radioactive waste

    International Nuclear Information System (INIS)

    1985-12-01

    The feasibility of safe ocean disposal options for heat-generating radioactive waste relies on the existence of suitable disposal sites. This review considers the status of the development of site selection criteria and the results of the study area investigations carried out under various national and international research programmes. In particular, the usefulness of the results obtained is related to the data needed for environmental and emplacement modelling. Preliminary investigations have identified fifteen potential deep ocean study areas in the North Atlantic. From these Great Meteor East (GME), Southern Nares Abyssal Plan (SNAP) and Kings Trough Flank (KTF) were selected for further investigation. The review includes appraisals of regional geology, geophysical studies, sedimentology, geotechnical studies, geochemical studies and oceanography. (author)

  3. Geological disposal of heat generating radioactive waste

    International Nuclear Information System (INIS)

    1986-03-01

    A number of options for the disposal of vitrified heat-generating radioactive waste are being studied to ensure that safe methods are available when the time comes for disposal operations to commence. This study has considered the feasibility of three designs for containers which would isolate the waste from the environment for a minimum period of 500 to 1000 years. The study was sub-divided into the following major sections: manufacturing feasibility; stress analysis; integrity in accidents; cost benefit review. The candidate container designs were taken from the results of a previous study by Ove Arup and Partners (1985) and were developed as the study progressed. Their major features can be summarised as follows: (A) a thin-walled corrosion-resistant metal shell filled with lead or cement grout. (B) an unfilled thick-walled carbon steel shell. (C) an unfilled carbon steel shell planted externally with corrosion-resistant metal. Reference repository conditions in clay, granite and salt, reference disposal operations and metals corrosion data have been taken from various European Community radioactive waste management research and engineering projects. The study concludes that design Types A and B are feasible in manufacturing terms but design Type C is not. It is recommended that model containers should be produced to demonstrate the proposed methods of manufacture and that they should be tested to validate the analytical techniques used. (author)

  4. Ocean disposal of heat generating radioactive waste

    International Nuclear Information System (INIS)

    1985-11-01

    The detailed radiological assessment of any proposed operations for the disposal of heat-generating radioactive waste in deep ocean sediments would require data describing expected embedment depths and spacing of the waste. In this study a theoretical model which predicts penetrator trajectories from launch through to rest in the sediment has been produced and has been used to generate data for environmental models. The trajectory model has been used to study the effects of small imperfections and launch parameters on the motion of a reference penetrator through water and sediment. The model predicts that the horizontal displacements of the penetrators' final resting places in the sediment from their launch positions at the ocean surface could be limited to less than 15m by twisting their tail fins uniformly by just one degree to induce spinning. The reference penetrator is predicted to achieve satisfactory embedment depth for all the cases considered including allowance for the effect of curved penetration paths in the seabed. However, the ability of the model to represent highly non-linear sediment penetration paths is demonstrated. Distribution histograms of seabed impact points relative to specific release points are presented. The area of seabed required is calculated. (author)

  5. Ocean disposal of heat generating radioactive waste

    International Nuclear Information System (INIS)

    1984-12-01

    A study of container designs for heat generating radioactive waste disposal in the deep ocean sediments is presented. The purpose of the container would be to isolate the waste from the environment for a period of 500 to 1000 years. The container designs proposed are based on the use of either corrosion allowance or corrosion resistant metals. Appropriate overpack wall thicknesses are suggested for each design using the results of corrosion studies and experiments but these are necessarily preliminary and data relevant to corrosion in deep ocean sediments remain sparse. It is concluded that the most promising design concept involves a thin titanium alloy overpack in which all internal void spaces are filled with lead or cement grout. In situ temperatures for the sediment adjacent to the emplaced 50 year cooled waste containers are calculated to reach about 260 deg C. The behaviour of the sediments at such a high temperature is not well understood and the possibility of 100 years interim storage is recommended for consideration to allow further cooling. Further corrosion data and sediment thermal studies would be required to fully confirm the engineering feasibility of these designs. (author)

  6. Ocean disposal of heat generating radioactive waste

    International Nuclear Information System (INIS)

    1984-07-01

    This report is based on an emplacement techniques review prepared for the Department of the Environment in February 1983, which appeared as Chapter III of the Nuclear Energy Agency, Seabed Working Group's Status Report. The original document (DOE/RW/83.032) has been amended to take account of the results of field trials carried out in March 1983 and to better reflect current UK Government policy on ocean disposal of HGW. In particular Figure 7 has been redrawn using more realistic drag factors for the calculation of the terminal velocity in water. This report reviews the work conducted by the SWG member countries into the different techniques of emplacing heat generating radioactive waste into the deep ocean sediments. It covers the waste handling from the port facilities to final emplacement in the seabed and verification of the integrity of the canister isolation system. The two techniques which are currently being considered in detail are drilled emplacement and the free fall penetrator. The feasibility study work in progress for both techniques as well as the mathematical and physical modelling work for embedment depth and hole closure behind the penetrator are reviewed. (author)

  7. Geological disposal of heat generating radioactive waste

    International Nuclear Information System (INIS)

    1985-02-01

    A study has been made of the requirements and design features for containers to isolate vitrified heat generating radioactive waste from the environment for a period of 500 to 1000 years. The requirements for handling, storing and transporting containers have been identified following a study of disposal operations, and the pressures and temperatures which may possibly be experienced in clay, granite and salt formations have been estimated. A range of possible container designs have been proposed to satisfy the requirements of each of the disposal environments. Alternative design concepts in corrosion resistant or corrosion allowance material have been suggested. Potentially suitable container shell materials have been selected following a review of corrosion studies and although metals have not been specified in detail, titanium alloys and low carbon steels are thought to be appropriate for corrosion resistant and corrosion allowance designs respectively. Performance requirements for container filler materials have been identified and candidate materials assessed. A preliminary container stress analysis has shown the importance of thermal modelling and that if lead is used as a filler it dominates the stress response of the container. Possible methods of manufacturing disposal containers have been assessed and found to be generally feasible. (author)

  8. Radioactive wastes with negligible heat generation suitable for disposal

    International Nuclear Information System (INIS)

    Brennecke, P.; Schumacher, J.; Warnecke, E.

    1987-01-01

    It is planned to dispose of radioactive wastes with negligible heat generation in the Konrad repository. Preliminary waste acceptance requirements are derived taking the results of site-specific safety assessments as a basis. These requirements must be fulfilled by the waste packages on delivery. The waste amounts which are currently stored and those anticipated up to the year 2000 are discussed. The disposability of these waste packages in the Konrad repository was evaluated. This examination reveals that basically almost all radioactive wastes with negligible heat generation can be accepted. (orig.) [de

  9. Management of radioactive wastes with negligible heat generation

    International Nuclear Information System (INIS)

    Alter, U.

    1990-01-01

    In the Federal Republic of Germany only one company is responsible for the management of radioactive wastes with negligible heat generations. This is the Company for Nuclear Service (GNS mbH). It was the intention of the competent authorities of the FRG to intensify state control during conditioning, intermediate storage and transport of low- and medium level radioactive waste. A guideline provides that the responsibility of the waste producers and of those concerned with conditioning, storage and transport of radioactive waste is assigned in the individual case and that the qualitative and quantitative registration of all waste streams will be ensured. An overview of the radioactive waste management within the last two years in the FRG is presented. (orig./DG)

  10. Physical limits on steam generation by radioactive decay heat

    International Nuclear Information System (INIS)

    Chesnut, D.A.

    1991-12-01

    This report briefly discusses the possibilities that flood water contacting the hot radioactive waste and rock at Yucca Mountain could produce enough steam to lift the top of the mountain off the repository

  11. Radioactivity and decay heat generation in precambrian magmatic rocks (with the South Pamirs as an example)

    International Nuclear Information System (INIS)

    Batyrmurzaev, A.S.; Alibekov, G.I.; Bekieva, A.A.

    2003-01-01

    The evaluation of the heat generation share in the results of the long-living radioactive elements (RAE) decay in the Earth surface layers is accomplished on the basis of the data on the uranium and thorium concentration in the precambrian magmatic rocks of the South Pamirs. It was supposed by the calculations, that the value of the heat flux, generated by the rocks, is determined mainly by the RAE content in the Earth upper layer crust itself of 10-15 km. It is shown that the radioheat generation share is within the range of 5-10% from the measured values of the geothermal flows [ru

  12. A computer code for calculation of radioactive nuclide generation and depletion, decay heat and γ ray spectrum. FPGS90

    International Nuclear Information System (INIS)

    Ihara, Hitoshi; Katakura, Jun-ichi; Nakagawa, Tsuneo

    1995-11-01

    In a nuclear reactor radioactive nuclides are generated and depleted with burning up of nuclear fuel. The radioactive nuclides, emitting γ ray and β ray, play role of radioactive source of decay heat in a reactor and radiation exposure. In safety evaluation of nuclear reactor and nuclear fuel cycle, it is needed to estimate the number of nuclides generated in nuclear fuel under various burn-up condition of many kinds of nuclear fuel used in a nuclear reactor. FPGS90 is a code calculating the number of nuclides, decay heat and spectrum of emitted γ ray from fission products produced in a nuclear fuel under the various kinds of burn-up condition. The nuclear data library used in FPGS90 code is the library 'JNDC Nuclear Data Library of Fission Products - second version -', which is compiled by working group of Japanese Nuclear Data Committee for evaluating decay heat in a reactor. The code has a function of processing a so-called evaluated nuclear data file such as ENDF/B, JENDL, ENSDF and so on. It also has a function of making figures of calculated results. Using FPGS90 code it is possible to do all works from making library, calculating nuclide generation and decay heat through making figures of the calculated results. (author)

  13. A computer code for calculation of radioactive nuclide generation and depletion, decay heat and {gamma} ray spectrum. FPGS90

    Energy Technology Data Exchange (ETDEWEB)

    Ihara, Hitoshi; Katakura, Jun-ichi; Nakagawa, Tsuneo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1995-11-01

    In a nuclear reactor radioactive nuclides are generated and depleted with burning up of nuclear fuel. The radioactive nuclides, emitting {gamma} ray and {beta} ray, play role of radioactive source of decay heat in a reactor and radiation exposure. In safety evaluation of nuclear reactor and nuclear fuel cycle, it is needed to estimate the number of nuclides generated in nuclear fuel under various burn-up condition of many kinds of nuclear fuel used in a nuclear reactor. FPGS90 is a code calculating the number of nuclides, decay heat and spectrum of emitted {gamma} ray from fission products produced in a nuclear fuel under the various kinds of burn-up condition. The nuclear data library used in FPGS90 code is the library `JNDC Nuclear Data Library of Fission Products - second version -`, which is compiled by working group of Japanese Nuclear Data Committee for evaluating decay heat in a reactor. The code has a function of processing a so-called evaluated nuclear data file such as ENDF/B, JENDL, ENSDF and so on. It also has a function of making figures of calculated results. Using FPGS90 code it is possible to do all works from making library, calculating nuclide generation and decay heat through making figures of the calculated results. (author).

  14. Radionuclide inventory and heat generation analysis in disposal of radioactive waste

    International Nuclear Information System (INIS)

    Suryanto

    1997-01-01

    Radionuclide inventory and heat generation analysis on spent nuclear fuel were done in order to study the potential radionuclides contributing radiological impact to human being caused by spent fuel disposal. The study was carried out using the Bateman equation of radionuclide decay chains for fission products and actinides. the results showed that Cs-137, Sr-90 and Pu-239 dominated inventory of spent fuel, in which Pu-238 and Pu-240 dominated heat generation during disposal. Accordingly, the above radionuclides could be considered as the reference radionuclides for safety analysis of spent nuclear fuel disposal (author)

  15. Radioactive material generator

    International Nuclear Information System (INIS)

    Czaplinski, T.V.; Bolter, B.J.; Heyer, R.E.; Bruno, G.A.

    1975-01-01

    A radioactive material generator includes radioactive material in a column, which column is connected to inlet and outlet conduits, the generator being embedded in a lead casing. The inlet and outlet conduits extend through the casing and are topped by pierceable closure caps. A fitting, containing means to connect an eluent supply and an eluate container, is adapted to pierce the closure caps. The lead casing and the fitting are compatibly contoured such that they will fit only if properly aligned with respect to each other

  16. The thermal analysis of low heat generating radioactive wastes in land disposal facilities

    International Nuclear Information System (INIS)

    Lympany, S.D.

    1984-08-01

    A procedure is developed which allows a simple thermal analysis of a radioactive waste repository. The procedure is used to establish if the thermally induced groundwater flow is important when considering the transport of radionuclides from the repository, and thereby indicates if this flow should be taken into account in a detailed thermal assessment. (author)

  17. Refinancing of the search for a repository and of the repository for heat generating radioactive waste. Pt. 1

    International Nuclear Information System (INIS)

    Moench, Christoph

    2013-01-01

    The final disposal of radioactive waste is a state task that is assigned to the Federal Government pursuant to section 9a (3) sentence 1 of the Atomic Energy Act (AtG). Since the early 1970's, the Federal Government has been actively searching for and exploring final disposal sites for radioactive waste. In a proceeding accompanied by the intensive participation of technical experts and the public, the Gorleben salt dome (Salzstock) has emerged as a presumably suitable disposal site from a mining standpoint (eignungshoeffig) according to the current status of the exploration. The cost of these exploratory measures - and the subsequent construction - will be financed by the waste producers, in particular the utility companies, by means of advance payments on their contributions. Part I of this article will evaluate the selection and exploration of the Gorleben salt dome to date and examine the provisions on the pre-financing burden from the point of view of constitutional law. Constitutional objections can also be raised against the regulation in section 21b (4) AtG that was introduced in 1998, which excludes a refunding of the pre-financing contributions even if the repository is never erected or operated. Part II of this article, which will appear in the next issue, will take up the question of whether a search for an alternative repository site, as the Federal Ministry for the Environment (BMU) envisions in the working draft of an 'Act on the search for and selection of a site for a repository for heat generating radioactive waste' (Gesetz zur Suche und Auswahl eines Standortes fuer ein Endlager fuer waermeentwickelnde radioaktive Abfaelle), is likewise to be refinanced as a contribution by the parties obliged to make advance payments. (orig.)

  18. The Konrad mine - the planned German repository for radioactive waste with negligible heat generation

    International Nuclear Information System (INIS)

    Berg, H.P.; Brennecke, P.

    1990-07-01

    This report deals with the planned Konrad repository and describes the current state of affairs. In particular, the technical concept is explained and a survey of the radioactive waste intended for disposal is given. The safety assessments which have been made, including the derivation of preliminary waste acceptance requirements, are described and the principles of the waste package control are outlined. (orig./HP) [de

  19. Reloadable radioactive generator system

    International Nuclear Information System (INIS)

    Colombetti, L.G.

    1977-01-01

    A generator system that can be reloaded with an elutable radioactive material, such as 99 molybdenum, a multiple number of times is described. The system basically comprises a column filled with alumina, a loading vial containing a predetermined amount of the elutable radioactive material, and a rinsing vial containing a sterile solution. The two vials are connected by a conduit so that when communication is achieved between the column and loading vial and an evacuated vial is placed in communication with the bottom of the column, the predetermined amount of the radioactive material in the loading vial will be transferred to the column. The procedure can be repeated as the elutable material in the column is dissipated

  20. Rechargeable radioactive isotope generator

    International Nuclear Information System (INIS)

    Thornton, A.K.; Cerone, F.E.

    1978-01-01

    The description is given of a rechargeable radioactive isotope generator having the following features: a box containing a transport shield, a shielded generator including elements for the absorption and holding of the parent isotope, an eluant tank, a first pipe causing this tank to communicate with the transport shield, a second pipe causing this transport shield to communicate with the shielded generator and a third pipe placing the shielded generator in communication with the outside of the unit. It also includes a shelf across the external front part of the unit a part of which is shielded by external components, a shielded elution flask in which the eluate is poured and a filter set at a point between the flask and the third pipe [fr

  1. Concept for an ultimate storage facility for heat-generating radioactive waste in clay stone in Germany

    International Nuclear Information System (INIS)

    Bollingerfehr, Wilhelm; Poehler, Matthias

    2010-01-01

    According to the German reference ultimate storage concept heat-generating radioactive waste from the operation of nuclear power stations should be stored permanently maintenance-free and in a non-recoverable manner in a salt formation. Within the framework of investigations into the utilisation of alternative host rocks a concept for an ultimate storage facility in clay stone was developed in an R and D project. For this purpose all important aspects of the design, development, operation and shutdown were taken into account for a model region in northern Germany. It was established that storage in 50 m deep vertical boreholes in a mine at a depth of about 350 m appears to be the most practical solution for an ultimate storage facility in clay stone. Compared to the reference concept in salt an ultimate storage facility in clay stone requires solid support of all mine openings with steel arches or shotcrete. Because of the lower maximum permissible temperature in the backfilling material (bentonite) the area required for the ultimate storage facility is about five times larger. A period of more than 100 years is estimated from survey to shutdown. (orig.)

  2. Refinancing of the search for a repository and of the repository for heat generating radioactive Waste. Pt. 2

    International Nuclear Information System (INIS)

    Moench, Christoph

    2013-01-01

    Part I of this article, which appeared in the preceding issue, described in general terms the background to the search for a disposal site and the result of the exploration to date of the repository, which would appear to be suitable from a mining standpoint according to the present knowledge. According to the rules in effect up to now, the exploration and construction would be financed by advance payments on the contributions of the waste producing companies, in particular the utility companies. The working draft of an 'Act on the search for and selection of a site for a repository for heat generating radioactive waste' (Gesetz zur Suche und Auswahl eines Standortes fuer ein Endlager fuer waermeentwickelnde radioaktive Abfaelle) from autumn 2012 provides for a new version of section 21b Atomic Energy Act, under which the costs for 'carrying out a repository selection procedure pursuant to the Repository Selection Act (Standort-auswahlgesetz)' would be allocated to the future users of the repository who are obliged to make contributions as a 'necessary expense'. Part II evaluates this provision of the working draft on the basis of the financial constitutional law. A comparison of sites is not a measure that could be allocated to the future users of the repository who are obliged to make contributions as a 'necessary expense'. Moreover, there is a lack of responsibility for the financing and of a legally relevant advantage that would be conferred by a cumulative alternative repository search for the later users of the repository who are obliged to provide the pre-financing. The costs can therefore not be allocated to the later users as either a contribution or a special charge, not even by way of an association with mandatory membership (Zwangsverband). They must be borne by the state. Consequently, the allocation stipulated by provision would constitute an impermissible charge under financial constitutional law. (orig.)

  3. Dynamics of radioactive waste generation

    International Nuclear Information System (INIS)

    Dogaru, Daniela; Virtopeanu, Cornelia; Ivan, Alexandrina

    2008-01-01

    In Romania there are in operation three facilities licensed for collection, treatment and storage of radioactive waste resulted from industry, research, medicine, and agriculture, named institutional radioactive waste. The repository, which is of near surface type, is designed for disposing institutional radioactive waste. The institutional radioactive wastes generated are allowed to be disposed into repository according to the waste acceptance criteria, defined for the disposal facility. The radioactive wastes which are not allowed for disposal are stored on the site of each facility which is special authorised for this. The paper describes the dynamics of generation of institutional waste in Romania, both for radioactive waste which are allowed to be disposed into repository and for radioactive waste which are not allowed to be disposed of. (authors)

  4. Requirements for a long-term safety certification for chemotoxic substances stored in a final storage facility for high radioactive and heat-generating radioactive waste in rock salt formations

    International Nuclear Information System (INIS)

    Tholen, M.; Hippler, J.; Herzog, C.

    2007-01-01

    Within the scope of a project funded by the German Federal Ministry of Economics and Technology (Bundesministerium fuer Wirtschaft und Technologie, BMWi), a safety certification concept for a future permanent final storage for high radioactive and heat-generating radioactive waste (HAW disposal facility) in rock salt formations is being prepared. For a reference concept, compliance with safety requirements in regard to operational safety as well as radiological and non-radiological protection objectives related to long-term safety, including ground water protection, will be evaluated. This paper deals with the requirements for a long-term safety certification for the purpose of protecting ground water from chemotoxic substances. In particular, longterm safety certifications for the permanent disposal of radioactive waste in a HAW disposal facility in rock salt formations and for the dumping of hazardous waste in underground storage facilities in rock salt formations are first discussed, followed by an evaluation as to whether these methods can be applied to the long-term safety certification for chemotoxic substances. The authors find it advisable to apply the long-term safety certification for underground storage facilities to the long-term safety certification for chemotoxic substances stored in a HAW disposal facility in rock salt formations. In conclusion, a corresponding certification concept is introduced. (orig.)

  5. Development of vault model 'VERMIN' for post closure behaviour of repositories for non-heat generating radioactive wastes

    International Nuclear Information System (INIS)

    1983-10-01

    The computer model VERMIN has been developed to simulate the post closure time dependent behaviour of the vault section of a Land 3 and a Land 2 type repository. Development was carried out within the constraints of the computer code SYVAC. Output from the new model, in terms of radionuclide fluxes versus time, provides the source term for that code. A number of conceptual designs for different geological conditions were produced and used to develop the model. Unlike SYVAC, the boundary of the vault was considered to be at the interface between the damaged rock zone and the undamaged host rock. VERMIN treats the vault as a series of engineered barriers namely: waste matrix, waste package, backfill material liner and the damaged rock zone. For the Land 3 repository, the vault was considered to be fully saturated and consequently corrosion, leading to eventual package failure, will occur. VERMIN allows for package failure and subsequent leaching and then calculates the migration of nuclides from within the vault out to its boundary. One dimensional advection and two dimensional diffusion/dispersion are modelled allowing for retardation due to sorption radionuclide saturation and radionuclide decay. Radioactive decay chains up to eight members can be modelled by VERMIN. (author)

  6. Joule-Heated Ceramic-Lined Melter to Vitrify Liquid Radioactive Wastes Containing Am241 Generated From MOX Fuel Fabrication in Russia

    International Nuclear Information System (INIS)

    Smith, E C; Bowan II, B W; Pegg, I; Jardine, L J

    2004-01-01

    contains. Silver is widely used as an additive in glass making. However, its solubility is known to be limited in borosilicate glasses. Further, silver, which is present as a nitrate salt in the waste, can be easily reduced to molten silver in the melting process. Molten silver, if formed, would be difficult to reintroduce into the glass matrix and could pose operating difficulties for the glass melter. This will place a limitation on the waste loading of the melter feed material to prevent the separation of silver from the waste within the melter. If the silver were recovered in the MOx fabrication process, which is currently under consideration, the composition of the glass would likely be limited only by the thermal heat load from the incorporated 241 Am. The resulting mass of glass used to encapsulate the waste could then be reduced by a factor of approximately three. The vitrification process used to treat the waste stream is proposed to center on a joule-heated ceramic lined slurry fed melter. Glass furnaces of this type are used in the United States to treat high-level waste (HLW) at the: Defense Waste Processing Facility, West Valley Demonstration Project, and to process the Hanford tank waste. The waste will initially be blended with glass-forming chemicals, which are primarily sand and boric acid. The resulting slurry is pumped to the melter for conversion to glass. The melter is a ceramic lined metal box that contains a molten glass pool heated by passing electric current through the glass. Molten glass from the melter is poured into canisters to cool and solidify. They are then sealed and decontaminated to form the final waste disposal package. Emissions generated in the melter from the vitrification process are treated by an off-gas system to remove radioactive contamination and destroy nitrogen oxides (NOx)

  7. Micro thrust and heat generator

    Science.gov (United States)

    Garcia, E.J.

    1998-11-17

    A micro thrust and heat generator have a means for providing a combustion fuel source to an ignition chamber of the micro thrust and heat generator. The fuel is ignited by a ignition means within the micro thrust and heat generator`s ignition chamber where it burns and creates a pressure. A nozzle formed from the combustion chamber extends outward from the combustion chamber and tappers down to a narrow diameter and then opens into a wider diameter where the nozzle then terminates outside of said combustion chamber. The pressure created within the combustion chamber accelerates as it leaves the chamber through the nozzle resulting in pressure and heat escaping from the nozzle to the atmosphere outside the micro thrust and heat generator. The micro thrust and heat generator can be microfabricated from a variety of materials, e.g., of polysilicon, on one wafer using surface micromachining batch fabrication techniques or high aspect ratio micromachining techniques (LIGA). 30 figs.

  8. Heat and electricity generating methods

    International Nuclear Information System (INIS)

    Buter, J.

    1977-01-01

    A short synopsis on the actual methods of heating of lodgings and of industrial heat generation is given. Electricity can be generated in steam cycles heated by burning of fossil fuels or by nuclear energy. A valuable contribution to the electricity economy is produced in the hydroelectric power plants. Besides these classical methods, also the different procedures of direct electricity generation are treated: thermoelectric, thermionic, magnetohydrodynamic power sources, solar and fuel cells. (orig.) [de

  9. Developments and studies on the (T)HMC processes in a final repository for heat generating radioactive wastes. Synthesis and final report; Entwicklungen und Untersuchungen zu (T)HMC-Prozessen eines Endlagers fuer Waerme entwickelnde radioaktive Abfaelle. Synthese und Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Weyand, Torben [Bonn Univ. (Germany); Bracke, Guido; Fischer, Heidemarie; Frieling, Gerd; Hansmeier, Christina; Hotzel, Stephan; Kock, Ingo; Seher, Holger

    2014-10-15

    The report on developments and studies on the (T)HMC (thermal-hydraulic-mechanical-chemical) processes in a final repository for heat generating radioactive wastes covers the following topics: description of the projects, applied codes: TOUGH2, FLAC3D, TOUGH2 and FLAC3D, TOUHREACT/PetraSim, MARNIE, PHREEQC, geochemists workbench, SUSA; safety relevant singular processes in the transition phase, uncertainties due to process interactions, coupling of mass transport and geochemical equilibria, further developments and application of numerical simulations in the transition phase.

  10. Environmental radioactivity at the heat power complex enterprises

    International Nuclear Information System (INIS)

    Krylov, D.A.; Putintseva, V.E.

    1997-01-01

    Environmental radioactivity at the heat power complex enterprises (coal mines, oil and gas deposits, coal thermal power plants and heat-electric generation plant) is considered. IT is shown that elevated level of radiation effect on the personnel lungs (2-3 times higher than that of safety standard) is observed at 80 coal mines. High levels of gamma radiation from natural radionuclides (300 μR/h and above) are marked at the separate objects of oil and gas mining industry. It is revealed that the contamination of ash wastes resulted from certain coals combustion reaches 520 Bq/kg at separate thermal power plants

  11. Next Generation Microchannel Heat Exchangers

    CERN Document Server

    Ohadi, Michael; Dessiatoun, Serguei; Cetegen, Edvin

    2013-01-01

    In Next Generation Microchannel Heat Exchangers, the authors’ focus on the new generation highly efficient heat exchangers and presentation of novel data and technical expertise not available in the open literature.  Next generation micro channels offer record high heat transfer coefficients with pressure drops much less than conventional micro channel heat exchangers. These inherent features promise fast penetration into many mew markets, including high heat flux cooling of electronics, waste heat recovery and energy efficiency enhancement applications, alternative energy systems, as well as applications in mass exchangers and chemical reactor systems. The combination of up to the minute research findings and technical know-how make this book very timely as the search for high performance heat and mass exchangers that can cut costs in materials consumption intensifies.

  12. Forest decline, natural and technically generated radioactivity

    International Nuclear Information System (INIS)

    Teufel, D.

    1983-06-01

    The question investigated is whether the radioactive rare gases emanating from nuclear plants are causative or participate in the triggering of forest disease. For one thing, a chemical reaction could be responsible for such an effect exerted by these artificial radioactive effluents. However, a calculation shows the concentration of radionuclides, respectively, in this case, their decomposition products, to be by many orders of magnitude smaller than other constituents in air; so a chemical reaction of this kind may be excluded. For the other part, rare gases might contribute to forest damage by their radioactive decomposition and late physical, chemical, and biological effects. In this connection, a detailed analysis is made of the comparability of natural radioactivity with radioactivity generated by nuclear plants. A possible contribution towards the total stress situation of forests (chemical air pollution, natural radioactivity, artificially produced radioactive rare gases, weather conditions and conditions arising from forest management and the like) would amount to a proportion smaller than 1/1000 considering natural radioactivity as a possible stress factor only. (orig.) [de

  13. The radioactive inventory of a Berkeley heat exchanger

    International Nuclear Information System (INIS)

    Hancock, R.

    1988-10-01

    The Central Electricity Generating Board has announced a date for the final shutdown of the first of the Magnox power stations at Berkeley (March 1989), and is in the process of preparing Pre-Decommissioning Safety Reports (PDSR) for the decommissioning of Berkeley and Bradwell. This report supports these PDSR studies and reports work carried out within the Research Division at Berkeley Nuclear Laboratories on the radioactive inventories of the heat exchangers at Berkeley Power Station. At Berkeley, the heat exchangers will be included in stage two decommissioning to which they will contribute the largest mass of contaminated material. The purpose of this report is to bring together all of the available data on the contamination in the heat exchangers at Berkeley Power Station, and to recommend a database from which the options for disposal of the heat exchangers may be formulated. (author)

  14. Final results of the 'Benchmark on computer simulation of radioactive nuclides production rate and heat generation rate in a spallation target'

    International Nuclear Information System (INIS)

    Janczyszyn, J.; Pohorecki, W.; Domanska, G.; Maiorino, R.J.; David, J.C.; Velarde, F.A.

    2011-01-01

    A benchmark has been organized to assess the computer simulation of nuclide production and heat generation in a spallation lead target. The physical models applied for the calculation of thick lead target activation do not produce satisfactory results for the majority of analysed nuclides, however one can observe better or worse quantitative compliance with the experimental results. Analysis of the quality of calculated results show the best performance for heavy nuclides (A: 170 - 190). For intermediate nuclides (A: 60 - 130) almost all are underestimated while for A: 130 - 170 mainly overestimated. The shape of the activity distribution in the target is well reproduced in calculations by all models but the numerical comparison shows similar performance as for the whole target. The Isabel model yields best results. As for the whole target heating rate, the results from all participants are consistent. Only small differences are observed between results from physical models. As for the heating distribution in the target it looks not quite similar. The quantitative comparison of the distributions yielded by different spallation reaction models shows for the major part of the target no serious differences - generally below 10%. However, in the most outside parts of the target front layers and the part of the target at its end behind the primary protons range, a spread higher than 40 % is obtained

  15. Heat generation and heating limits for the IRUS LLRW disposal facility

    International Nuclear Information System (INIS)

    Donders, R.E.; Caron, F.

    1995-10-01

    Heat generation from radioactive decay and chemical degradation must be considered when implementing low-level radioactive waste (LLRW) disposal. This is particularly important when considering the management of spent radioisotope sources. Heating considerations and temperature calculations for the proposed IRUS (Intrusion Resistant Underground Structure) near-surface disposal facility are presented. Heat transfer calculations were performed using a finite element code with realistic but somewhat conservative heat transfer parameters and environmental boundary conditions. The softening-temperature of the bitumen waste-form (38 deg C) was found to be the factor that limits the heat generation rate in the facility. This limits the IRUS heat rate, assuming a uniform source term, to 0.34 W/m 3 . If a reduced general heat-limit is considered, then some higher-heat packages can be accepted with restrictions placed on their location within the facility. For most LLRW, heat generation from radioactive decay and degradation are a small fraction of the IRUS heating limits. However, heating restrictions will impact on the disposal of higher-activity radioactive sources. High activity 60 Co sources will require decay-storage periods of about 70 years, and some 137 Cs will need to bed disposed of in facilities designed for higher-heat waste. (author). 21 refs., 8 tabs., 2 figs

  16. Heat generated by knee prostheses.

    Science.gov (United States)

    Pritchett, James W

    2006-01-01

    Temperature sensors were placed in 50 knees in 25 patients who had one or both joints replaced. Temperature recordings were made before walking, after walking, and after cycling. The heat generated in healthy, arthritic, and replaced knees was measured. The knee replacements were done using eight different prostheses. A rotating hinge knee prosthesis generated a temperature increase of 7 degrees C in 20 minutes and 9 degrees C in 40 minutes. An unconstrained ceramic femoral prosthesis articulating with a polyethylene tibial prosthesis generated a temperature increase of 4 degrees C compared with a healthy resting knee. The other designs using a cobalt-chrome alloy and high-density polyethylene had temperature increases of 5 degrees-7 degrees C with exercise. Frictional heat generated in a prosthetic knee is not immediately dissipated and may result in wear, creep, and other degenerative processes in the high-density polyethylene. Extended periods of elevated temperature in joints may inhibit cell growth and perhaps contribute to adverse performance via bone resorption or component loosening. Prosthetic knees generate more heat with activity than healthy or arthritic knees. More-constrained knee prostheses generate more heat than less-constrained prostheses. A knee with a ceramic femoral component generates less heat than a knee with the same design using a cobalt-chromium alloy.

  17. Generating cryptographic keys by radioactive decays

    International Nuclear Information System (INIS)

    Grupen, Claus; Maurer, Ingo; Schmidt, Dieter; Smolik, Ludek

    2001-01-01

    We are presenting a new method for the generation of statistically genuine random bitstream with very high frequency which can be employed for cryptographic purposes. The method uses the feature of statistically unpredictable radioactive decays as the source of randomness. The measured quantity is the time distance between the responses of a small ionisation chamber due to the recording of ionising decay products. This time measurement is converted into states representing 0o r 1. The data generated in our experiment successfully passed FIPS PUB 140-1 and die hard statistical tests. For the simulation of systematic effects Monte Carlo techniques were used

  18. Heat operated cryogenic electrical generator

    International Nuclear Information System (INIS)

    Fletcher, J.C.; Wang, T.C.; Saffren, M.M.; Elleman, D.D.

    1975-01-01

    An electrical generator useful for providing electrical power in deep space, is disclosed. The subject electrical generator utilizes the unusual hydrodynamic property exhibited by liquid helium as it is converted to and from a superfluid state to cause opposite directions of rotary motion for a rotor cell thereof. The physical motion of said rotor cell is employed to move a magnetic field provided by a charged superconductive coil mounted on the exterior of said cell. An electrical conductor is placed in surrounding proximity to said cell to interact with the moving magnetic field provided by the superconductive coil and thereby generate electrical energy. A heat control arrangement is provided for the purpose of causing the liquid helium to be partially converted to and from a superfluid state by being cooled and heated, respectively. (U.S.)

  19. Modelling gas generation in radioactive waste repositories

    International Nuclear Information System (INIS)

    Agg, P.J.

    1993-02-01

    In a repository containing low- and intermediate-level waste, gas generation will occur principally by the coupled processes of metal corrosion and microbial degradation of cellulosic waste. This Paper describes a mathematical model design to address gas generation by these mechanisms. The metal corrosion model incorporates a three-stage process encompassing both aerobic and anaerobic corrosion regimes; the microbial degradation model simulates the activities of eight different microbial populations, which are maintained as functions both of pH and of the concentrations of particular chemical species. Gas concentrations have been measured over a period of three years in large-scale drum experiments designed to simulate repository conditions. Model predictions are confirmed against the experimental measurements, and a prediction is then made of gas concentrations and generation rates over an assessment period of one million years in a radioactive waste repository. (author)

  20. Modelling gas generation in radioactive waste repositories

    International Nuclear Information System (INIS)

    Agg, P.J.

    1992-07-01

    In a repository containing low- and intermediate-level waste, gas generation will occur principally by the coupled processes of metal corrosion and microbial degradation of cellulosic waste. This paper describes a mathematical model designed to address gas generation by these mechanisms. The metal corrosion model incorporates a three-stage process encompassing both aerobic and anaerobic corrosion regimes; the microbial degradation model simulates the activities of eight different microbial populations, which are maintained as functions both of pH and of the concentrations of particular chemical species. Gas concentrations have been measured over a period of three years in large-scale drum experiments designed to simulate repository conditions. Model predictions are confirmed against the experimental measurements, and a prediction is then made of gas concentrations and generation rates over an assessment period of one million years in a radioactive waste repository. (Author)

  1. Engineering product storage under the advanced fuel cycle initiative. Part I: An iterative thermal transport modeling scheme for high-heat-generating radioactive storage forms

    International Nuclear Information System (INIS)

    Kaminski, Michael D.

    2005-01-01

    The US Department of Energy is developing an integrated nuclear fuel cycle technology under its Advanced Fuel Cycle Initiative (AFCI). Under the AFCI, waste minimization is stressed. Engineered product storage materials will be required to store concentrated radioactive cesium, strontium, americium, and curium for periods of tens to hundreds of years. The fabrication of such engineered products has some precedence but the concept is largely novel. We thus present a theoretical model used to calculate the maximum radial dimensions of right cylinder storage forms under several scenarios. Maximum dimensions are small, comparable to nuclear fuel pins in some cases, to avoid centerline melting temperatures; this highlights the need for a careful strategy for engineered product storage fabrication and storage

  2. A review of biological studies sponsored by the Department of the Environment to assist feasibility studies of the disposal of heat generating radioactive waste in the deep ocean

    International Nuclear Information System (INIS)

    Allen, J.A.; Gale, G.

    1985-04-01

    The report review recent biological studies on the organisms of the deep sea and takes into account the physical and chemical parameters that influence them. Particular attention is devoted to studies funded by the Department of the Environment to determine the technical feasibility of disposing of high level radioactive wastes in the deep sea. Such quantitative information that exists concerning the input and output of organic material into the abyss is given. This information is related to the diversity, growth, size, and reproductive biology of the abyssal infauna and epifauna and to the organisms within the water column above. Life processes, under the influence of high pressure are discussed and related to the uptake by and release from organisms of radiochemicals. Gaps in our present knowledge of the total ecosystem are identified and recommendations for future studies made. (author)

  3. Stress analysis of HTR-10 steam generator heat exchanging tubes

    International Nuclear Information System (INIS)

    Dong Jianling; Zhang Xiaohang; Yin Dejian; Fu Jiyang

    2001-01-01

    Steam Generator (SG) heat exchanging tubes of 10 MW High Temperature Gas Cooled Reactor (HTR-10) are protective screens between the primary loop of helium with radioactivity and the secondary loop of feeding water and steam without radioactivity. Water and steam will enter into the primary loop when rupture of the heat exchanging tubes occurs, which lead to increase of the primary loop pressure and discharge of radioactive materials. Therefore it is important to guarantee the integrity of the tubes. The tube structure is spiral tube with small bending radius, which make it impossible to test with volumetric in-service detection. For such kind of spiral tube, using LBB concept to guarantee the integrity of the tubes is an important option. The author conducts stress analysis and calculation of HTR-10 SG heat exchanging tubes using the FEM code of piping stress analysis, PIPESTRESS. The maximum stress and the dangerous positions are obtained

  4. Radioactivity transport following steam generator tube rupture

    International Nuclear Information System (INIS)

    Hopenfeld, J.

    1985-03-01

    A review of the capabilities of the CITADEL computer code as well as plant experience to project radioactivity releases following a steam generator tube rupture in PWR's shows that certain experimental data are needed for reliable off-site dose predictions. This article defines five parameters which are the key for such predictions and discusses the functional dependence of these parameters on various operational variables. The above parameters can be used in conjunction with CITADEL or they can be inserted in the appropriate equations which then conveniently can be programmed as a subroutine in thermal-hydraulic system codes. A joint Westinghouse, Electric Power Research Institute and Nuclear Regulatory Commission Program aimed at obtaining the five parameters empirically is described

  5. Ocean disposal of heat generating radioactive waste

    International Nuclear Information System (INIS)

    1984-08-01

    The operational and technical feasibility of the penetrator option for HGW disposal has been reviewed and the areas where research is required to confirm feasibility have been identified. The research requirements have been presented against the Department's ocean disposal programme timescale on a series of bar charts. The bar charts show the need for theoretical and experimental studies of the basic mechanisms governing hole closure and the development of suitable instrumentation to assess the actual behaviour of the remoulded sediment in deep ocean trials. Detailed planning of deep ocean trials in sufficient time to develop strategy, models and instrumentation, identification of site investigation requirements and thermal response studies of sediments are also required. (author)

  6. Heat transfer in vitrified radioactive waste

    International Nuclear Information System (INIS)

    Palancar, M.C.; Luis, M.A.; Luis, P.; Aragon, J.M.; Montero, M.A.

    1987-01-01

    An experimental method for measuring the thermal conductivity and convection coefficient of borosilicate glass cylinders, containing a simulated high level radioactive waste, is described. A simulation of the thermal behaviour of matrices of solidified waste during the cooling in air, water and a geological repository has been done. The experimental values of the thermal conductivity are ranging from 0.267 to 0.591 w/m K, for matrices with simulated waste contents of 10 to 40% (the waste is simulated by no radioactive isotopes). The convection coefficient for air/cylinders under the operating conditions used is 116 w/m 2 K. The simulated operation of cooling in air shows that about 1-2 days are enough to cool a solidified waste cylinder 0.6m diameter from 900 to 400 0 C. The cooling under water from 400 to near 80 0 C is faster than in air, but sharp temperature gradients within the matrices could be expected. The simulation of geological repositories lead to some criteria of arranging the matrices for avoiding undesirable high temperature points. (author) 1 fig

  7. Heat pipe cooling system for underground, radioactive waste storage tanks

    International Nuclear Information System (INIS)

    Cooper, K.C.; Prenger, F.C.

    1980-02-01

    An array of 37 heat pipes inserted through the central hole at the top of a radioactive waste storage tank will remove 100,000 Btu/h with a heat sink of 70 0 F atmospheric air. Heat transfer inside the tank to the heat pipe is by natural convection. Heat rejection to outside air utilizes a blower to force air past the heat pipe condenser. The heat pipe evaporator section is axially finned, and is constructed of stainless steel. The working fluid is ammonia. The finned pipes are individually shrouded and extend 35 ft down into the tank air space. The hot tank air enters the shroud at the top of the tank and flows downward as it is cooled, with the resulting increased density furnishing the pressure difference for circulation. The cooled air discharges at the center of the tank above the sludge surface, flows radially outward, and picks up heat from the radioactive sludge. At the tank wall the heated air rises and then flows inward to comple the cycle

  8. Method for removal of decay heat of radioactive substances

    International Nuclear Information System (INIS)

    Hesky, H.; Wunderer, A.

    1981-01-01

    In this process, the decay heat from radioactive substances is removed by means of a liquid carried in the coolant loop. The liquid is partially evaporated by the decay heat. The steam is used to drive the liquid through the loop. When a static pressure level equivalent to the pressure drop in the loop is exceeded, the steam is separated from the liquid, condensed, and the condensate is reunited with the return flow of liquid for partial evaporation. (orig.) [de

  9. Method for utilizing decay heat from radioactive nuclear wastes

    International Nuclear Information System (INIS)

    Busey, H.M.

    1974-01-01

    Management of radioactive heat-producing waste material while safely utilizing the heat thereof is accomplished by encapsulating the wastes after a cooling period, transporting the capsules to a facility including a plurality of vertically disposed storage tubes, lowering the capsules as they arrive at the facility into the storage tubes, cooling the storage tubes by circulating a gas thereover, employing the so heated gas to obtain an economically beneficial result, and continually adding waste capsules to the facility as they arrive thereat over a substantial period of time

  10. Natural convection in heat-generating fluids

    International Nuclear Information System (INIS)

    Bol'shov, Leonid A; Kondratenko, Petr S; Strizhov, Valerii F

    2001-01-01

    Experimental and theoretical studies of convective heat transfer from a heat-generating fluid confined to a closed volume are reviewed. Theoretical results are inferred from analytical estimates based on the relevant conservation laws and the current understanding of the convective heat-transfer processes. Four basic and one asymptotic regime of heat transfer are identified depending on the heat generation rate. Limiting heat-transfer distribution patterns are found for the lower boundary. Heat transfer in a quasi-two-dimensional geometry is analyzed. Quasi-steady-state heat transfer from a cooling-down fluid without internal heat sources is studied separately. Experimental results and theoretical predictions are compared. (reviews of topical problems)

  11. Self-disposal option for heat-generating waste - 59182

    International Nuclear Information System (INIS)

    Ojovan, Michael I.; Poluektov, Pavel P.; Kascheev, Vladimir A.

    2012-01-01

    Self-descending heat generating capsules can be used for disposal of dangerous radioactive wastes in extremely deep layers of the Earth preventing any release of radionuclides into the biosphere. Self-disposal option for heat-generating radioactive waste such as spent fuel, high level reprocessing waste or spent sealed radioactive sources, known also as rock melting concept, was considered in the 70's as a viable alternative disposal option by both Department of Energy in the USA and Atomic Industry Ministry in the USSR. Self-disposal is currently reconsidered as a potential alternative route to existing options for solving the nuclear waste problem and is associated with the renaissance of nuclear industry. Self- disposal option utilises the heat generated by decaying radionuclides of radioactive waste inside a heavy and durable capsule to melt the rock on its way down. As the heat from radionuclides within the capsule partly melts the enclosing rock, the relatively low viscosity and density of the silicate melt allow the capsule to be displaced upwards past the heavier capsule as it sinks. Eventually the melt cools and solidifies (e.g. vitrifies or crystallizes), sealing the route along which the capsule passed. Descending or self-disposal continues until enough heat is generated by radionuclides to provide partial melting of surrounding rock. Estimates show that extreme depths of several tens and up to hundred km can be reached by capsules which could never be achieved by other techniques. Self- disposal does not require complex and expensive disposal facilities and provides a minimal footprint used only at operational stage. It has also an extremely high non- proliferation character and degree of safety. Utilisation of heat generated by relatively short-lived radionuclides diminishes the environmental uncertainties of self-disposal and increases the safety of this concept. Self-sinking heat-generating capsules could be launched from the bottom of the sea as

  12. Heat Generation by Irradiated Complex Composite Nanostructures

    DEFF Research Database (Denmark)

    Ma, Haiyan; Tian, Pengfei; Pello, Josselin

    2014-01-01

    Heating of irradiated metallic e-beam generated nanostructures was quantified through direct measurements paralleled by novel model-based numerical calculations. By comparing discs, triangles, and stars we showed how particle shape and composition determines the heating. Importantly, our results...... revealed that substantial heat is generated in the titanium adhesive layer between gold and glass. Even when the Ti layer is as thin as 2 nm it absorbs as much as a 30 nm Au layer and hence should not be ignored....

  13. 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

  14. Control system for fluid heated steam generator

    Science.gov (United States)

    Boland, J.F.; Koenig, J.F.

    1984-05-29

    A control system for controlling the location of the nucleate-boiling region in a fluid heated steam generator comprises means for measuring the temperature gradient (change in temperature per unit length) of the heating fluid along the steam generator; means for determining a control variable in accordance with a predetermined function of temperature gradients and for generating a control signal in response thereto; and means for adjusting the feedwater flow rate in accordance with the control signal.

  15. 4th Generation District Heating (4GDH)

    DEFF Research Database (Denmark)

    Lund, Henrik; Werner, Sven; Wiltshire, Robin

    2014-01-01

    This paper defines the concept of 4th Generation District Heating (4GDH) including the relations to District Cooling and the concepts of smart energy and smart thermal grids. The motive is to identify the future challenges of reaching a future renewable non-fossil heat supply as part...... of the implementation of overall sustainable energy systems. The basic assumption is that district heating and cooling has an important role to play in future sustainable energy systems – including 100 percent renewable energy systems – but the present generation of district heating and cooling technologies will have...

  16. Particle beam generator using a radioactive source

    Science.gov (United States)

    Underwood, D.G.

    1993-03-30

    The apparatus of the present invention selects from particles emitted by a radioactive source those particles having momentum within a desired range and focuses the selected particles in a beam having at least one narrow cross-dimension, and at the same time attenuates potentially disruptive gamma rays and low energy particles. Two major components of the present invention are an achromatic bending and focusing system, which includes sector magnets and quadrupole, and a quadrupole doublet final focus system. Permanent magnets utilized in the apparatus are constructed of a ceramic (ferrite) material which is inexpensive and easily machined.

  17. Distributed heat generation in a district heating system

    OpenAIRE

    Lennermo, Gunnar; Lauenberg, Patrick

    2016-01-01

    District heating (OH) systems need to be improved  regarding integration  of decentralised  heat generation. Micro production, prosumers and smart grids are terms becoming more and more common  in  connection  to  the  power  grid.  Concerning district  heating,  the  development  is slower, although improving. Today there are a number of such decentralised units for heat generation,  mainly  solar,  that have been partly evaluated.  Previous  studies  have shown  that there is a need to deve...

  18. Heat transfer enhancement in heat exchangers by longitudinal vortex generators

    International Nuclear Information System (INIS)

    Guntermann, T.; Fiebig, M.; Mitra, N.K.

    1990-01-01

    In this paper heat transfer enhancement and flow losses are computed for the interaction of a laminar channel flow with a pair of counterrotating longitudinal vortices generated by a pair of delta-winglets punched out of the channel wall. The geometry simulates an element of a fin-plate or fin-tube heat exchanger. The structure of the vortex flow and temperature distribution, the local heat transfer coefficients and the local flow losses are discussed for a sample case. For a Reynolds number of Re d = 1000 and a vortex generator angle of attack of β = 25 degrees heat transfer is enhanced locally by more than 300% and in the mean by 50%. These values increase further with Re and β

  19. Radioactive waste generated from JAERI partitioning-transmutation cycle system

    Energy Technology Data Exchange (ETDEWEB)

    Shinichi, Nakayama; Yasuji, Morita; Kenji, Nishihara [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan)

    2001-07-01

    Production of lower-level radioactive wastes, as well as the reduction in radioactivity of HLW, is an important performance indicator in assessing the viability of a partitioning-transmutation system. We have begun to identify the chemical compositions and to quantify the amounts of radioactive wastes that may be generated by JAERI processes. Long-lived radionuclides such as {sup 14}C and {sup 59}Ni and spallation products of Pb-Bi coolants are added to the existing inventory of these nuclides that are generated in the current fuel cycle. Spent salts of KCl-LiCl, which is not generated from the current fuel cycle, will be introduced as a waste. (author)

  20. Radioactive Wastes Generated From JAERI Partitioning-Transmutation Fuel Cycle

    International Nuclear Information System (INIS)

    Nakayama, Shinichi; Morita, Yasuji; Nishihara, Kenji

    2003-01-01

    Production of lower-level radioactive wastes, as well as the reduction in radioactivity of HLW, is an important performance indicator in assessing the viability of a partitioning-transmutation system. We have begun to identify the chemical compositions and to quantify the amounts of radioactive wastes that may be generated by JAERI's processes. Long-lived radionuclides such as 14 C and 59 Ni and spallation products of Pb-Bi coolants are added to the existing inventory of these nuclides that are generated in the current fuel cycle. Spent salts of KCl-LiCl, which is not generated from the current fuel cycle, will be introduced as a waste. (authors)

  1. Generation and release of radioactive gases in LLW disposal facilities

    Energy Technology Data Exchange (ETDEWEB)

    Yim, M.S. [Harvard School Public Health, Boston, MA (United States); Simonson, S.A. [Massachusetts Institute of Technology, Cambridge, MA (United States)

    1995-02-01

    The atmospheric release of radioactive gases from a generic engineered LLW disposal facility and its radiological impacts were examined. To quantify the generation of radioactive gases, detailed characterization of source inventory for carbon-14, tritium, iodine-129, krypton-85, and radon-222, was performed in terms of their activity concentrations; their distribution within different waste classes, waste forms and containers; and their subsequent availability for release in volatile or gaseous form. The generation of gases was investigated for the processes of microbial activity, radiolysis, and corrosion of waste containers and metallic components in wastes. The release of radionuclides within these gases to the atmosphere was analyzed under the influence of atmospheric pressure changes.

  2. Generation projection of solid and liquid radioactive wastes and spent radioactive sources in Mexico

    International Nuclear Information System (INIS)

    Garcia A, E.; Hernandez F, I. Y.; Fernandez R, E.; Monroy G, F.; Lizcano C, D.

    2014-10-01

    This work is focused to project the volumes of radioactive aqueous liquid wastes and spent radioactive sources that will be generated in our country in next 15 years, solids compaction and radioactive organic liquids in 10 years starting from the 2014; with the purpose of knowing the technological needs that will be required for their administration. The methodology involves six aspects to develop: the definition of general objectives, to specify the temporary horizon of projection, data collection, selection of the prospecting model and the model application. This approach was applied to the inventory of aqueous liquid wastes, as well as radioactive compaction organic and solids generated in Mexico by non energy applications from the 2001 to 2014, and of the year 1997 at 2014 for spent sources. The applied projection models were: Double exponential smoothing associating the tendency, Simple Smoothing and Lineal Regression. For this study was elected the first forecast model and its application suggests that: the volume of the compaction solid wastes, aqueous liquids and spent radioactive sources will increase respectively in 152%, 49.8% and 55.7%, while the radioactive organic liquid wastes will diminish in 13.15%. (Author)

  3. Heat flow and heat generation in greenstone belts

    Science.gov (United States)

    Drury, M. J.

    1986-01-01

    Heat flow has been measured in Precambrian shields in both greenstone belts and crystalline terrains. Values are generally low, reflecting the great age and tectonic stability of the shields; they range typically between 30 and 50 mW/sq m, although extreme values of 18 and 79 mW/sq m have been reported. For large areas of the Earth's surface that are assumed to have been subjected to a common thermotectonic event, plots of heat flow against heat generation appear to be linear, although there may be considerable scatter in the data. The relationship is expressed as: Q = Q sub o + D A sub o in which Q is the observed heat flow, A sub o is the measured heat generation at the surface, Q sub o is the reduced heat flow from the lower crust and mantle, and D, which has the dimension of length, represents a scale depth for the distribution of radiogenic elements. Most authors have not used data from greenstone belts in attempting to define the relationship within shields, considering them unrepresentative and preferring to use data from relatively homogeneous crystalline rocks. A discussion follows.

  4. Waste minimization for commercial radioactive materials users generating low-level radioactive waste

    International Nuclear Information System (INIS)

    Fischer, D.K.; Gitt, M.; Williams, G.A.; Branch, S.; Otis, M.D.; McKenzie-Carter, M.A.; Schurman, D.L.

    1991-07-01

    The objective of this document is to provide a resource for all states and compact regions interested in promoting the minimization of low-level radioactive waste (LLW). This project was initiated by the Commonwealth of Massachusetts, and Massachusetts waste streams have been used as examples; however, the methods of analysis presented here are applicable to similar waste streams generated elsewhere. This document is a guide for states/compact regions to use in developing a system to evaluate and prioritize various waste minimization techniques in order to encourage individual radioactive materials users (LLW generators) to consider these techniques in their own independent evaluations. This review discusses the application of specific waste minimization techniques to waste streams characteristic of three categories of radioactive materials users: (1) industrial operations using radioactive materials in the manufacture of commercial products, (2) health care institutions, including hospitals and clinics, and (3) educational and research institutions. Massachusetts waste stream characterization data from key radioactive materials users in each category are used to illustrate the applicability of various minimization techniques. The utility group is not included because extensive information specific to this category of LLW generators is available in the literature

  5. Current generation by minority-species heating

    International Nuclear Information System (INIS)

    Fisch, N.J.

    1981-01-01

    It is proposed that electric currents be generated from the preferential heating of ions travelling in one direction but with no net momentum injected into the system. This can be accomplished with, for example, travelling waves in a two-ion-species plasma. The current can be generated efficiently enough for the scheme to be of interest in maintaining steady-state toroidal currents in a reactor. (author)

  6. Current generation by minority species heating

    International Nuclear Information System (INIS)

    Fisch, N.J.

    1980-07-01

    It is proposed that electric currents be generated from the preferential heating of ions traveling in one direction but with no net momentum injected into the system. This can be accomplished with, for example, traveling waves in a two-ion-species plasma. The current can be generated efficiently enough for the scheme to be of interest in maintaining steady-state toroidal currents in a reactor

  7. Power generation from residual industrial heat

    International Nuclear Information System (INIS)

    Nguyen, T.Q.; Slawnwhite, J.D.; Boulama, K.Goni

    2010-01-01

    Industrial plants continuously reject large amounts of thermal energy through warm liquid or gaseous effluents during normal operation. These energy losses contribute to an inflation of production costs and also threaten the environment. This paper investigates methods of recovering the residual low grade thermal energy and converting it into higher quality mechanical energy using the thermodynamic Rankine cycle principle. For the temperature range of the available thermal energy, water was shown to be a poor working fluid for the conversion system, thus several potential working fluids, including ammonia, synthetic refrigerants, and organic compounds have been considered as alternatives. A comparative analysis led to the identification of different performance evaluation criteria. For example, the water-based Rankine cycle and, to a lesser extent, the ammonia-based Rankine cycle proved to be interesting when the power generation potential per unit working fluid mass flow rate was considered. On the other hand, Rankine-like cycles using dry hydrocarbon working fluids proved much more interesting in terms of energy conversion efficiency, as well as in terms of the net mechanical power generation potential for a given heat source. All performance indicators were low at low temperatures, and improved as the primary heat source was available at higher temperatures. This paper also discusses the influence of various external and internal operating parameters, such as heat source and heat sink temperatures, turbine and pump isentropic efficiencies and the addition of an internal heat exchanger on the overall performance of the energy recovery and conversion system.

  8. French nuclear power plants for heat generation

    International Nuclear Information System (INIS)

    Girard, Y.

    1984-01-01

    The considerable importance that France attributes to nuclear energy is well known even though as a result of the economic crisis and the energy savings it is possible to observe a certain downward trend in the rate at which new power plants are being started up. In July 1983, a symbolic turning-point was reached - at more than 10 thousand million kW.h nuclear power accounted, for the first time, for more than 50% of the total amount of electricity generated, or approx. 80% of the total electricity output of thermal origin. On the other hand, the direct contribution - excluding the use of electricity - of nuclear energy to the heat market in France remains virtually nil. The first part of this paper discusses the prospects and realities of the application, at low and intermediate temperatures, of nuclear heat in France, while the second part describes the French nuclear projects best suited to the heat market (excluding high temperatures). (author)

  9. Simultaneous power generation and heat recovery using a heat pipe assisted thermoelectric generator system

    International Nuclear Information System (INIS)

    Remeli, Muhammad Fairuz; Tan, Lippong; Date, Abhijit; Singh, Baljit; Akbarzadeh, Aliakbar

    2015-01-01

    Highlights: • A new passive power cogeneration system using industrial waste heat was introduced. • Heat pipes and thermoelectrics were used for recovering waste heat and electricity. • Theoretical model predicted the 2 kW test rig could recover 1.345 kW thermal power. • 10.39 W electrical power was produced equivalent to 0.77% conversion efficiency. - Abstract: This research explores a new method of recovering waste heat and electricity using a combination of heat pipes and thermoelectric generators (HP-TEG). The HP-TEG system consists of Bismuth Telluride (Bi 2 Te 3 ) based thermoelectric generators (TEGs), which are sandwiched between two finned heat pipes to achieve a temperature gradient across the TEG for thermoelectricity generation. A theoretical model was developed to predict the waste heat recovery and electricity conversion performances of the HP-TEG system under different parametric conditions. The modelling results show that the HP-TEG system has the capability of recovering 1.345 kW of waste heat and generating 10.39 W of electrical power using 8 installed TEGs. An experimental test bench for the HP-TEG system is under development and will be discussed in this paper

  10. Heat exchanger, particularly liquid sodium heated steam generator

    International Nuclear Information System (INIS)

    Robin, Marcel; Tillequin, Jean.

    1977-01-01

    This invention relates to a liquid sodium heated steam generator the characteristic of which is an annular distribution chamber fed by two independent and diametrically opposed manifolds on a common horizontal axis, issuing respectively into two adjacent compartments made in the chambers on both sides of a vertical transversal partition containing the axis of the casing and extending perpendicularly to the manifolds, each compartment being itself divided into a number of adjacent sectors marked by folded metal sheets fixed to the distributor and shaped so as to present in pairs and with the chamber opposite the manifold issuing into a compartment two independent ducts for distributing the sodium flow [fr

  11. The optimization of longitudinal convective fins with internal heat generation

    International Nuclear Information System (INIS)

    Razelos, P.

    1979-01-01

    The solution of the optimization problem for longitudinal convective fins of constant thickness, triangular or parabolic profile, and uniform internal heat generation, is presented. The cases considered are those of a given heat generation density, total heat generation and heat generation per unit width of the fin, when either the heat dissipation or the width of the fin is prescribed. The results are set forth in a nondimensional form, which are presented graphically. The effect of the fin's thermal conductivity upon the optimum dimensions is discussed, and limiting values for the heat generation and the heat dissipation, which may be imposed on the fin for a feasible optimization, are also obtained. (Auth.)

  12. Radioactive wastes: a problem of morality between generations

    International Nuclear Information System (INIS)

    MacLean, D.

    1984-01-01

    Nowhere are the intergenerational moral issues posed more explicitly that in debates over nuclear power and the disposal of radioactive wastes. A survey of some of the ethical issues covers energy supply and risk and the problem of determining a cost-benefit of resources use and conservation that maximizes supply and minimizes risk. The author identifies three arguments against energy policy based on cost-benefit analysis: 1 reliability, 2 fairness, and 3 the lack of subjective value. All three suggest the need to determine not only what our obligations to future generations are, but also the underlying basis of these obligations in our system of values. The radioactive waste issue has an urgency, for options are opening and closing. 13 references

  13. ULF Generation by Modulated Ionospheric Heating

    Science.gov (United States)

    Chang, C.; Labenski, J.; Wallace, T.; Papadopoulos, K.

    2013-12-01

    Modulated ionospheric heating experiments designed to generate ULF waves using the HAARP heater have been conducted since 2007. Artificial ULF waves in the Pc1 frequency range were observed from space and by ground induction magnetometers located in the vicinity of the heater as well as at long distances. Two distinct generation mechanisms of artificial ULF waves were identified. The first was electroject modulation under geomagnetically disturbed conditions. The second was pressure modulation in the E and F regions of the ionosphere under quiet conditions. Ground detections of ULF waves near the heater included both Shear Alfven waves and Magnetosonic waves generated by electrojet and/or pressure modulations. Distant ULF detections involved Magnetosonic wave propagation in the Alfvenic duct with pressure modulation as the most likely source. Summary of our observations and theoretical interpretations will be presented at the meeting. We would like to acknowledge the support provided by the staff at the HAARP facility during our ULF experiments.

  14. District heating and combined heat and power generation from biomass

    International Nuclear Information System (INIS)

    Veski, Rein

    1999-01-01

    An Altener programme seminar District Heating and Combined Heat and Power Generation from Biomass. Minitraining seminar and study tours and also Business forum, Exhibition and Short company presentations were held in Tallinn on March 21-23, 1999. The Seminar was organised by the VTT Energy, the Estonian Bioenergy Association and the Estonian Heat and Power Association in co-operation with the AFB-net. The Agricultural and Forestry Biomass Network (AFB-net) is part of the ALTENER programme. The Network aims at promoting and stimulating the implementation and commercial utilisation of energy from biomass and waste, through the initiation of business opportunities. This includes national and international co-operation and the exchange of the personnel. The Seminar was attended by consulting companies, scientists, municipal authorities and representatives of co-ordinating bodies engaged in renewable energy management as well as DH and CHP plant managers, equipment manufacturers and local energy planners from Finland, Estonia, Latvia, Lithuania, Sweden, Denmark, Belgium, Slovenia and Slovak Republic. At the Seminar minitraining issues were dealt with: the current situation and future trends in biomass DH in the Baltic Sea countries, and biomass DH and CHP in Eastern and Central Europe, planning and construction of biomass-based DH plants, biomass fuel procurement and handling technology, combustion technology, DH networks, financing of biomass projects and evaluating of projects, and case projects in Eastern and Central European countries. The following were presented: boilers with a capacity of 100 kW or more, stoker burners, wood and straw handling equipment, wood fuel harvesters, choppers, pelletisers, district heating pipelines and networks. (author)

  15. An overview of the transportation of radioactive waste at Ontario Power Generation facilities

    International Nuclear Information System (INIS)

    Holmes, P.

    2006-01-01

    The Radioactive Material Transportation Department (RMT) ensures regulatory compliance in radioactive material shipping within Ontario Power Generation (OPG). OPG provides a radioactive shipping program, high quality carrier service, stringent packaging maintenance, and quality assurance oversight to the corporation's nuclear facilities and its customers. This paper will speak to the transport of radioactive waste in Ontario Power Generation. It will also mention non-waste shipments and the quality assurance programme used at Ontario Power Generation to ensure a high quality transportation system. (author)

  16. Volume reduction of radioactive concrete waste generated from KRR-2 and UCP

    International Nuclear Information System (INIS)

    Min, B. Y.; Choi, W. K.; Park, J. W.; Lee, K. W.

    2009-01-01

    As a part of a technical development for the volume reduction and stabilization of contaminated concrete wastes generated by dismantling a research reactor and uranium conversion plant, we have developed the volume reduction technology and immobilization of fine powder applicable to an activated heavy weight concrete generated by dismantling KRR-2 and a uranium contaminated light weight concrete produced from a UCP decommissioning. During a decommissioning of nuclear plants and facilities, large quantities of contaminated concrete wastes are generated. The decommissioning of the retired TRIGA MARK II and III research reactors and a uranium conversion plant has been under way. In Korea, two decommissioning projects such as the decommissioning of the retired research reactors (KRR-1 and 2) and a uranium conversion plant (UCP) at the Korea Atomic Energy Research Institute (KAERI) has been carried out. By dismantling KRR-2, more than 260 tons of radioactive concrete wastes are generated among the total 2,000 tons of concrete wastes and more than 60 tons of concrete wastes contaminated with uranium compounds are generated in UCP decommissioning up to now. The volume reduction and recycling of the wastes is essential to reduce the waste management cost with expecting that an approximate disposal cost for low level radioactive waste will be more than 5,000 US dollars per 200 liter waste drum in Korea. It is well known that most of the radioactivity exist in cement mortar and paste composed of concrete. In this context, the volume reduction of concrete waste is based on the separation of radioactive concrete into a clean recyclable aggregates and a radioactive fine cement powder, which can be readily performed by heating to weaken the adherence force between the cement matrix and the aggregates followed by mechanical crushing and milling processes. In this study, we have investigated the characteristics of separation of aggregates and the distribution of radioactivity into

  17. Environmental impact statement on management of commercially generated radioactive wastes

    International Nuclear Information System (INIS)

    Shupe, M.W.; Kreiter, M.R.

    1979-01-01

    This report describes the generic environmental impact statement on the management of generated high-level and transuranic radioactive wastes. The contents of the statement are summarized. The alternatives considered include: geologic disposal; chemical resynthesis; very deep hole disposal; rock melting concept; island disposal; subseabed disposal; icesheet disposal; reverse well disposal; transmutation treatment; and space disposal concepts. The types and quantities of wastes considered are from 3 different fuel cycles for the LWR reactor: once through; uranium-only recycle; and uranium and platinum recycle

  18. Analysis of Heat Generation Mechanism in Ultrasound Infrared Thermography

    International Nuclear Information System (INIS)

    Choi, Man Yong; Lee, Seung Seok; Park, Jeong Hak; Kang, Ki Soo; Kim, Won Tae

    2009-01-01

    Heat generation mechanism of ultrasound infrared thermography is still not well understood, yet and there are two reliable assumptions of heat generation, friction and thermo-mechanical effect. This paper investigates the principal cause of heat generation at fatigue crack with experimental and numerical approach. Our results show most of heat generation is contributed by friction between crack interface and thermo-mechanical effect is a negligible quantity

  19. Analysis of a sandwich-type generator with self-heating thermoelectric elements

    International Nuclear Information System (INIS)

    Kim, Mikyung; Yang, Hyein; Wee, Daehyun

    2014-01-01

    Highlights: • A novel and unique type of thermoelectric generators is proposed. • Heat source is combined in thermoelectric elements, reducing heat transfer problems. • Embedding radioactive isotopes is proposed as a way to implement the new design. • Conversion efficiency and power density are estimated for the proposed design. - Abstract: A novel and unique design of thermoelectric generators, in which a heat source is combined with thermoelectric elements, is proposed. By placing heat-generating radioactive isotopes inside the thermoelectric elements, the heat transfer limitation between the generator and the heat source can be eliminated, ensuring simplicity. The inner electrode is sandwiched between identical thermoelectric elements, which naturally allows the inner core to act as the hot side. Analysis shows that conversion efficiency and power density increase as the heat density inside the thermoelectric elements increases and as the thermoelectric performance of the material improves. The theoretical maximum efficiency is shown to be 50%. However, realistic performance under practical constraint is much worse. In realistic cases, the efficiency would be about 3% at best. The power density of the proposed design exhibits a much more reasonable value as high as 3000 W/m 2 . Although the efficiency is low, the simplicity of the proposed design combined with its reasonable power density may result in some, albeit limited, potential applications. Further investigation must be performed in order to realize such potential

  20. Radioactive Waste Generation in Pyro-SFR Nuclear Fuel Cycle

    International Nuclear Information System (INIS)

    Gao, Fanxing; Park, Byung Heung; Ko, Won Il

    2011-01-01

    Which nuclear fuel cycle option to deploy is of great importance in the sustainability of nuclear power. SFR fuel cycle employing pyroprocessing (named as Pyro- SFR Cycle) is one promising fuel cycle option in the near future. Radioactive waste generation is a key criterion in nuclear fuel cycle system analysis, which considerably affects the future development of nuclear power. High population with small territory is one special characteristic of ROK, which makes the waste management pretty important. In this study, particularly the amount of waste generation with regard to the promising advanced fuel cycle option was evaluated, because the difficulty of deploying an underground repository for HLW disposal requires a longer time especially in ROK

  1. A Modified Entropy Generation Number for Heat Exchangers

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    This paper demonstrates the difference between the entropy generation number method proposed by Bejian and the method of entropy generation per unit amount of heat transferred in analyzing the ther-modynamic performance of heat exchangers,points out the reason for leading to the above difference.A modified entropy generation number for evaluating the irreversibility of heat exchangers is proposed which is in consistent with the entropy generation per unit amount of heat transferred in entropy generation analysis.The entropy generated by friction is also investigated.Results show that when the entropy generated by friction in heat exchangers in taken into account,there is a minimum total entropy generation number while the NTU and the ratio of heat capacity rates vary.The existence of this minimum is the prerequisite of heat exchanger optimization.

  2. Basic approach to the disposal of low level radioactive waste generated from nuclear reactors containing comparatively high radioactivity

    International Nuclear Information System (INIS)

    Moriyama, Yoshinori

    1998-01-01

    Low level radioactive wastes (LLW) generated from nuclear reactors are classified into three categories: LLW containing comparatively high radioactivity; low level radioactive waste; very low level radioactive waste. Spent control rods, part of ion exchange resin and parts of core internals are examples of LLW containing comparatively high radioactivity. The Advisory Committee of Atomic Energy Commission published the report 'Basic Approach to the Disposal of LLW from Nuclear Reactors Containing Comparatively High Radioactivity' in October 1998. The main points of the proposed concept of disposal are as follows: dispose of underground deep enough not be disturb common land use (e.g. 50 to 100 m deep); dispose of underground where radionuclides migrate very slowly; dispose of with artificial engineered barrier which has the same function as the concrete pit; control human activities such as land use of disposal site for a few hundreds years. (author)

  3. Nuclear power generation and global heating

    International Nuclear Information System (INIS)

    Taboada, Horacio

    1999-01-01

    The Professionals Association and Nuclear Activity of National Atomic Energy Commission (CNEA) are following with great interest the worldwide discussions on global heating and the role that nuclear power is going to play. The Association has an active presence, as part of the WONUC (recognized by the United Nations as a Non-Governmental Organization) in the COP4, which was held in Buenos Aires in November 1998. The environmental problems are closely related to human development, the way of power production, the techniques for industrial production and exploitation fields. CO 2 is the most important gas with hothouse effects, responsible of progressive climatic changes, as floods, desertification, increase of average global temperature, thermal expansion in seas and even polar casks melting and ice falls. The consequences that global heating will have on the life and economy of human society cannot be sufficiently emphasized, great economical impact, destruction of ecosystems, loss of great coast areas and complete disappearance of islands owing to water level rise. The increase of power retained in the atmosphere generates more violent hurricanes and storms. In this work, the topics presented in the former AATN Meeting is analyzed in detail and different technological options and perspectives to mitigate CO 2 emission, as well as economical-financial aspects, are explored. (author)

  4. Ocean disposal of heat generating waste

    International Nuclear Information System (INIS)

    1985-06-01

    A number of options for the disposal of vitrified heat generating waste are being studied to ensure that safe methods are available when the time comes for disposal operations to commence. This study has considered the engineering and operational aspects of the Penetrator Option for ocean disposal to enable technical comparisons with other options to be made. In the Penetrator Option concept, waste would be loaded into carefully designed containers which would be launched at a suitable deep ocean site where they would fall freely through the water and would embed themselves completely within the seabed sediments. Radiological protection would be provided by a multi-barrier system including the vitrified waste form, the penetrator containment, the covering sediment and the ocean. Calculations and demonstration have shown that penetrators could easily achieve embedment depths in excess of 30m and preliminary radiological assessments indicate that 30m of intact sediment would be an effective barrier for radionuclide isolation. The study concludes that a 75mm thickness of low carbon steel appears to be sufficient to provide a containment life of 500 to 1000 years during which time the waste heat output would have decayed to an insignificant level. Disposal costs have been assessed. (author)

  5. Economical photovoltaic power generation with heat recovery

    Science.gov (United States)

    Ascher, G.

    1977-01-01

    Three designs for conversion of solar radiation to electricity and thermal energy are analyzed. The objective of these converters is to increase the electric and thermal output for each photovoltaic array so as to lower the cell cost relative to the amount of energy delivered. An analysis of the economical aspects of conversion by photovoltaic cells with heat recovery is carried out in terms of hypothetical examples. Thus, it is shown that the original cost of say $40,000 per generated kilowat can be reduced to $572.00 per kilowatt by increasing the original electric output of 1 kW to 10 kW in electricity and 60 kW in thermal energy. The newly derived specific cost is only 1.4 percent of the original one. It is expected that a cost reduction of roughly 2% of the present specific cost per kilowatt will greatly stimulate public acceptance of photovoltaic terrestrial conversion to electricity.

  6. Next Generation Nuclear Plant Intermediate Heat Exchanger Acquisition Strategy

    Energy Technology Data Exchange (ETDEWEB)

    Mizia, Ronald Eugene [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2008-04-01

    DOE has selected the High Temperature Gas-cooled Reactor (HTGR) design for the Next Generation Nuclear Plant (NGNP) Project. The NGNP will demonstrate the use of nuclear power for electricity and hydrogen production. It will have an outlet gas temperature in the range of 900°C to 950°C and a plant design service life of 60 years. The reactor design will be a graphite moderated, helium cooled, prismatic or pebble-bed reactor, and use low-enriched uranium, TRISO-coated fuel. The plant size, reactor thermal power, and core configuration will ensure passive decay heat removal without fuel damage or radioactive material releases during accidents. The NGNP Materials Research and Development (R&D) Program is responsible for performing R&D on likely NGNP materials in support of the NGNP design, licensing, and construction activities. Selection of the technology and design configuration for the NGNP must consider both the cost and risk profiles to ensure that the demonstration plant establishes a sound foundation for future commercial deployments. The NGNP challenge is to achieve a significant advancement in nuclear technology while at the same time setting the stage for an economically viable deployment of the new technology in the commercial sector soon after 2020. The purpose of this report is to address the acquisition strategy for the NGNP Intermediate Heat Exchanger (IHX).This component will be operated in flowing, impure helium on the primary and secondary side at temperatures up to 950°C. There are major high temperature design, materials availability, and fabrication issues that need to be addressed. The prospective materials are Alloys 617, 230, 800H and X, with Alloy 617 being the leading candidate for the use at 950°C. The material delivery schedule for these materials does not pose a problem for a 2018 start up as the vendors can quote reasonable delivery times at the moment. The product forms and amount needed must be finalized as soon as possible. An

  7. Heat transfer enhancement for fin-tube heat exchanger using vortex generators

    International Nuclear Information System (INIS)

    Yoo, Seong Yeon; Park, Dong Seong; Chung, Min Ho; Lee, Sang Yun

    2002-01-01

    Vortex generators are fabricated on the fin surface of a fin-tube heat exchanger to augment the convective heat transfer. In addition to horseshoe vortices formed naturally around the tube of the fin-tube heat exchanger, longitudinal vortices are artificially created on the fin surface by vortex generators. The purpose of this study is to investigate the local heat transfer phenomena in the fin-tube heat exchangers with and without vortex generators, and to evaluate the effect of vortices on the heat transfer enhancement. Naphthalene sublimation technique is employed to measure local mass transfer coefficients, then analogy equation between heat and mass transfer is used to calculate heat transfer coefficients. Experiments are performed for the model of fin-circular tube heat exchangers with and without vortex generators, and of fin-flat tube heat exchangers with and without vortex generators. Average heat transfer coefficients of fin-flat tube heat exchanger without vortex generator are much lower than those of fin-circular tube heat exchanger. On the other hand, fin-flat tube heat exchanger with vortex generators has much higher heat transfer value than conventional fin-circular tube heat exchanger. At the same time, pressure losses for four types of heat exchanger is measured and compared

  8. Legal protection issues with regard to the site selection of a final repository for heat-generating radioactive wastes; Rechtsschutzfragen hinsichtlich der Standortauswahl eines Endlagers fuer waermeentwickelnde radioaktive Abfaelle

    Energy Technology Data Exchange (ETDEWEB)

    Keienburg, Bettina [KUEMMERLEIN Rechtsanwaelte und Notare, Essen (Germany)

    2014-10-15

    The site selection law (hereinafter StandAG) adopted on 23.07 2013 and entirely entered into force on 01.01.2014 shall clarify especially the site selection question of a final repository for highly radioactive waste until the year 2031. For this purpose, the act regulates a comprehensive procedure with multiple public participations and multiple interventions of the legislator. Thus the legislator hopes for an accepted dispute decision on a permanent basis - meaning acceptance. It remains to be seen, if this expectation is realistic. The StandAG and the decisions provided already rise potential for dispute. Added to this is a large number of dispute potential with regard to scouting out in connection with the site selection - despite of legal regulations for scouting out sites and remaining sites- and required authorisation. The potential shall be reported below.

  9. Gas generation phenomena in radioactive waste transportation packaging

    International Nuclear Information System (INIS)

    Nigrey, P.J.

    1998-01-01

    The interaction of radiation from radioactive materials with the waste matrix can lead to the deterioration of the waste form resulting in the possible of gaseous species. Depending on the type and characteristics of the radiation source, the generation of hydrogen may predominate. Since the interaction of alpha particles with the waste form results in significant energy transfer, other gases such as carbon oxides, methane, nitrogen oxides, oxygen, water, and helium are possible. The type of gases produced from the waste forms is determined by the mechanisms involved in the waste degradation. For transuranic wastes, the identified degradation mechanisms are reported to be caused by radiolysis, thermal decomposition or dewatering, chemical corrosion, and bacterial action. While all these mechanisms may be responsible for the building of gases during the storage of wastes, radiolysis and thermal decomposition appear to be main contributors during waste transport operations. (authors)

  10. Heat wave generates questions about Ontario's generation capacity

    International Nuclear Information System (INIS)

    Horne, D.

    2005-01-01

    Concerns regarding Ontario's power generation capacity were raised following a major blackout which occurred in August 2003. Power demand reached 26,170 MW during the weeks leading to the blackout, forcing the Independent Electricity System Operator (IESO) to ask residents to reduce electricity use during the day. The grid operator had also issued a forecast that Toronto could face rolling blackouts during times of heavy power demand. Ontario power consumption records were set in June and July of 2003 due to a heat wave, with hourly demand exceeding 25,000 MW on 53 occasions. Ontario was forced to import up to 3,400 MW (13 per cent of its power needs) from neighbouring provinces and the United States. During that period, the price of power had risen sharply to over 30 cents a kilowatt hour, although household consumers were still charged in the 5 to 10 cent range per kilowatt hour. However, it was noted that taxpayers will eventually bear the cost of importing power. The IESO noted that importing electricity is cheaper than the generation available in Ontario and that it is more economical to import, based on the market clearing price of all generators. In 2004, the IESO purchased 6 per cent of their electricity from the United States. That figure is expected to increase for 2005. Ontario generators produced 26.9 million MWh more in the summer of 2005 than during the same period in 2004 to meet electricity demand levels. It was noted that although importing power presently meets peak demand, the IESO agrees there is a need for new generation within Ontario. In addition to restarting Ontario's Pickering and Bruce nuclear facilities, more than 3,300 MW of new gas-fired generation is under construction or approved, and more than 9,000 MW are in various stages of approval. This paper discussed the effect of high energy costs on industry and Ontario's ability to meet future electricity demand in comparison to neighbouring jurisdictions. Issues regarding grid maintenance

  11. Thermal mechanical analysis of applications with internal heat generation

    Science.gov (United States)

    Govindarajan, Srisharan Garg

    The radioactive tracer Technetium-99m is widely used in medical imaging and is derived from its parent isotope Molybedenum-99 (Mo-99) by radioactive decay. The majority of Molybdenum-99 (Mo-99) produced internationally is extracted from high enriched uranium (HEU) dispersion targets that have been irradiated. To alleviate proliferation risks associated with HEU-based targets, the use of non-HEU sources is being mandated. However, the conversion of HEU to LEU based dispersion targets affects the Mo-99 available for chemical extraction. A possible approach to increase the uranium density, to recover the loss in Mo-99 production-per-target, is to use an LEU metal foil placed within an aluminum cladding to form a composite structure. The target is expected to contain the fission products and to dissipate the generated heat to the reactor coolant. In the event of interfacial separation, an increase in the thermal resistance could lead to an unacceptable rise in the LEU temperature and stresses in the target. The target can be deemed structurally safe as long as the thermally induced stresses are within the yield strength of the cladding and welds. As with the thermal and structural safety of the annular target, the thermally induced deflection of the BORALRTM-based control blades, used by the University of Missouri Research Reactor (MURRRTM ), during reactor operation has been analyzed. The boron, which is the neutron absorber in BORAL, and aluminum mixture (BORAL meat) and the aluminum cladding are bonded together through powder metallurgy to establish an adherent bonded plate. As the BORAL absorbs both neutron particles and gamma rays, there is volumetric heat generation and a corresponding rise in temperature. Since the BORAL meat and aluminum cladding materials have different thermal expansion coefficients, the blade may have a tendency to deform as the blade temperature changes and the materials expand at different rates. In addition to the composite nature of the

  12. Toward 4th generation district heating

    DEFF Research Database (Denmark)

    Li, Hongwei; Svendsen, Svend; Dalla Rosa, Alessandro

    2014-01-01

    In many countries, district heating (DH) has a key role in the national strategic energy planning. However, tighter legislation on new and future buildings requires much less heating demand which subsequently causes relative high network heat loss. This will make current DH system uneconomical co...

  13. Targets for ion sources for RIB generation at the Holifield Radioactive Ion Beam Facility

    International Nuclear Information System (INIS)

    Alton, G.D.

    1995-01-01

    The Holifield Radioactive Ion Beam Facility (HRIBF), now under construction at the Oak Ridge National Laboratory, is based on the use of the well-known on-line isotope separator (ISOL) technique in which radioactive nuclei are produced by fusion type reactions in selectively chosen target materials by high-energy proton, deuteron, or He ion beams from the Oak Ridge Isochronous Cyclotron (ORIC). Among several major challenges posed by generating and accelerating adequate intensities of radioactive ion beams (RIBs), selection of the most appropriate target material for production of the species of interest is, perhaps, the most difficult. In this report, we briefly review present efforts to select target materials and to design composite target matrix/heat-sink systems that simultaneously incorporate the short diffusion lengths, high permeabilities, and controllable temperatures required to effect maximum diffusion release rates of the short-lived species that can be realized at the temperature limits of specific target materials. We also describe the performance characteristics for a selected number of target ion sources that will be employed for initial use at the HRIBF as well as prototype ion sources that show promise for future use for RIB applications

  14. Emissions of soot particles from heat generators

    Science.gov (United States)

    Lyubov, V. K.; Popov, A. N.; Popova, E. I.

    2017-11-01

    «Soot carbon» or «Soot» - incomplete combustion or thermal decomposition particulate carbon product of hydrocarbons consisting of particles of various shapes and sizes. Soot particles are harmful substances Class 2 and like a dust dispersed by wind for thousands of kilometers. Soot have more powerful negative factor than carbon dioxide. Therefore, more strict requirements on ecological and economical performance for energy facilities at Arctic areas have to be developed to protect fragile Arctic ecosystems and global climate change from degradation and destruction. Quantity of soot particles in the flue gases of energy facilities is a criterion of effectiveness for organization of the burning process. Some of heat generators do not provide the required energy and environmental efficiency which results in irrational use of energy resources and acute pollution of environment. The paper summarizes the results of experimental study of solid particles emission from wide range of capacity boilers burning different organic fuels (natural gas, fuel oil, coal and biofuels). Special attention is paid to environmental and energy performance of the biofuels combustion. Emissions of soot particles PM2.5 are listed. Structure, composition and dimensions of entrained particles with the use of electronic scanning microscope Zeiss SIGMA VP were also studied. The results reveal an impact of several factors on soot particles emission.

  15. Heat generation during plunge stage in friction stir welding

    Directory of Open Access Journals (Sweden)

    Veljić Darko M.

    2013-01-01

    Full Text Available This paper deals with the heat generation in the Al alloy Al2024-T3 plate under different rotating speeds and plunge speeds during the plunge stage of friction stir welding (FSW. A three-dimensional finite element model (FEM is developed in the commercial code ABAQUS/Explicit using the arbitrary Lagrangian-Eulerian formulation, the Johnson-Cook material law and Coulomb’s Law of friction. The heat generation in FSW can be divided into two parts: frictional heat generated by the tool and heat generated by material deformation near the pin and the tool shoulder region. Numerical results obtained in this work indicate a more prominent influence from the friction-generated heat. The slip rate of the tool relative to the workpiece material is related to this portion of heat. The material velocity, on the other hand, is related to the heat generated by plastic deformation. Increasing the plunging speed of the tool decreases the friction-generated heat and increases the amount of deformation-generated heat, while increasing the tool rotating speed has the opposite influence on both heat portions. Numerical results are compared with the experimental ones, in order to validate the numerical model, and a good agreement is obtained.

  16. Entropy and heat generation of lithium cells/batteries

    International Nuclear Information System (INIS)

    Wang Songrui

    2016-01-01

    The methods and techniques commonly used in investigating the change of entropy and heat generation in Li cells/batteries are introduced, as are the measurements, calculations and purposes. The changes of entropy and heat generation are concomitant with the use of Li cells/batteries. In order to improve the management and the application of Li cells/batteries, especially for large scale power batteries, the quantitative investigations of the change of entropy and heat generating are necessary. (topical review)

  17. Project CHRISTA. Feasibility study on the development of a safety demonstration methodology for a final repository for heat generating radioactive wastes in crystalline rock formations in Germany; Projekt CHRISTA. Machbarkeitsuntersuchung zur Entwicklung einer Sicherheits- und Nachweismethodik fuer ein Endlager fuer Waerme entwickelnde radioaktive Abfaelle im Kristallingestein in Deutschland

    Energy Technology Data Exchange (ETDEWEB)

    Jobmann, Michael (ed.)

    2016-10-24

    In the frame of CHRISTA several options with different safety concepts for the final disposal of heat generating radioactive wastes were studied. The German safety requirements and the demonstration of the geological barrier integrity are based on an enclosure concept (ewG) that was developed primarily for salt and clay formations. The applicability of these requirements for crystalline host rocks had to be investigated. The enclosure functio0n is based on low hydraulic permeability of the host rock in combination with geotechnical barriers closing the access. With respect to the transferability of the Swedish/Finnish KBS-3 concept it has to be remarked, that the national standards in Sweden and Finland require the safety demonstration for 100.000 years (in Germany 1 million years). The Swedish/Finish container concept is based on a copper sheathed container with adjacent buffer; MOX fuel elements are not foreseen. The report concludes that the actual German safety concept based on geological barriers is to be preferred compared to technical barriers.

  18. Thermal decomposition of woody wastes contaminated with radioactive materials using externally-heated horizontal kiln

    International Nuclear Information System (INIS)

    Iwasaki, Toshiyuki; Kato, Shigeru; Yamasaki, Akihiro; Ito, Takuya; Suzuki, Seiichi; Kojima, Toshinori; Kodera, Yoichi; Hatta, Akimichi; Kikuzato, Masahiro

    2015-01-01

    Thermal decomposition experiments of woody wastes contaminated with radioactive materials were conducted using an externally-heated horizontal kiln in the work area for segregation of disaster wastes at Hirono Town, Futaba County, Fukushima Prefecture. Radioactivity was not detected in gaseous products of thermal decomposition at 923 K and 1123 K after passage through a trap filled with activated carbon. The contents of radioactive cesium ( 134 Cs and 137 Cs) were measured in the solid and liquid products of the thermal decomposition experiments and in the residues in the kiln after all of the experiments. Although a trace amount of radioactive cesium was found in the washing trap during the start-up period of operation at 923 K, most of the cesium remained in the char, including the residues in the kiln. These results suggest that most of the radioactive cesium is trapped in char particles and is not emitted in gaseous form. (author)

  19. 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.

  20. Feasibility of deep ocean disposal of heat generating waste. V.1

    International Nuclear Information System (INIS)

    Hemming, C.R.

    1988-06-01

    This report summarises the research performed in the UK during the period 1977 to 1987 as part of the international programme investigating the feasibility of ocean disposal of heat generating radioactive waste. This study has involved: (i) the definition of the disposal operations needed to meet the minimum requirements for safely emplacing waste on or under the floor of the deep ocean; (ii) the identification and characterisation of areas of the deep ocean that might be suitable for containing heat generating waste; (iii) a study of the processes by which radionuclides might migrate through the multiple barriers that isolate the waste from man's environment; and (iv) a calculation of the radiological impact of the conceptual deep ocean repository. It is concluded that, from a technical and scientific viewpoint, disposal of heat generating waste in the deep ocean could provide a safe, economic and feasible alternative to deep disposal on land. (author)

  1. The thermo-mechanical behaviour of a salt dome with a heat-generating waste repository

    International Nuclear Information System (INIS)

    Janssen, L.G.J.; Prij, J.; Kevenaar, J.W.A.M.; Jong, C.J.T.; Klok, J.; Beemsterboer, C.

    1984-01-01

    This report reviews the analytical work on the disposal of radioactive waste in salt domes performed at ECN in the period 1 January 1980 to 31 December 1982. Chapter 4 in the main report covers the global temperature and deformation analyses of the salt dome and the surrounding rocks. The attached three topical reports cover self-contained parts of the study. The computer program TASTE developed to analyse, at acceptable cost and with, for engineering purposes, sufficient accuracies, the temperature rises in the salt dome due to the stored heat-generating waste is described in Annex 1. Annex 2 gives a description of the extended finite element program GOLIA. The program has been extended to make it suitable for the creep analysis of salt domes with repositories of heat-generating waste. The study on the closing and sealing of boreholes wit heat-generating waste is reported in Annex 3

  2. Heat flow, heat generation and crustal thermal structure of the northern block of the South Indian Craton

    Science.gov (United States)

    Gupta, Mohan L.; Sharma, S. R.; Sundar, A.

    Heat flow values and heat generation data calculated from the concentration of heat producing radioactive elements, U, Th and K in surface rocks were analyzed. The South Indian Craton according to Drury et al., can be divided into various blocks, separated by late Proterozoic shear belts. The northern block comprises Eastern and Western Dharwar Cratons of Rogers (1986), Naqvi and Rogers (1987) and a part of the South Indian granulite terrain up to a shear system occupying the Palghat-Cauvery low lands. The geothermal data analysis clearly demonstrates that the present thermal characteristics of the above two Archaean terrains of the Indian and Australian Shields are quite similar. Their crustal thermal structures are likely to be similar also.

  3. Heat flow, heat generation and crustal thermal structure of the northern block of the South Indian Craton

    Science.gov (United States)

    Gupta, Mohan L.; Sharma, S. R.; Sundar, A.

    1988-01-01

    Heat flow values and heat generation data calculated from the concentration of heat producing radioactive elements, U, Th and K in surface rocks were analyzed. The South Indian Craton according to Drury et al., can be divided into various blocks, separated by late Proterozoic shear belts. The northern block comprises Eastern and Western Dharwar Cratons of Rogers (1986), Naqvi and Rogers (1987) and a part of the South Indian granulite terrain up to a shear system occupying the Palghat-Cauvery low lands. The geothermal data analysis clearly demonstrates that the present thermal characteristics of the above two Archaean terrains of the Indian and Australian Shields are quite similar. Their crustal thermal structures are likely to be similar also.

  4. Generator-absorber-heat exchange heat transfer apparatus and method and use thereof in a heat pump

    Science.gov (United States)

    Phillips, B.A.; Zawacki, T.S.

    1998-07-21

    Numerous embodiments and related methods for generator-absorber heat exchange (GAX) are disclosed, particularly for absorption heat pump systems. Such embodiments and related methods use, as the heat transfer medium, the working fluid of the absorption system taken from the generator at a location where the working fluid has a rich liquor concentration. 5 figs.

  5. Heat Recovery From Tail Gas Incineration To Generate Power

    Energy Technology Data Exchange (ETDEWEB)

    Tawfik, Tarek

    2010-09-15

    Many industrial processes result in tail gas wastes that must be flared or incinerated to abide with environmental guidelines. Tail gas incineration occurs in several chemical processes resulting in high-temperature exhaust gas that simply go to the stack, thus wasting all that valuable heat! This paper discusses useful heat recovery and electric power generation utilizing available heat in exhaust gas from tail gas incinerators. This heat will be recovered in a waste-heat recovery boiler that will produce superheated steam to expand in a steam turbine to generate power. A detailed cost estimate is presented.

  6. Laminar fluid flow and heat transfer in a fin-tube heat exchanger with vortex generators

    Energy Technology Data Exchange (ETDEWEB)

    Yanagihara, J.I.; Rodriques, R. Jr. [Polytechnic School of Univ. of Sao Paolo, Sao Paolo (Brazil). Dept. of Mechanical Engineering

    1996-12-31

    Development of heat transfer enhancement techniques for fin-tube heat exchangers has great importance in industry. In recent years, heat transfer augmentation by vortex generators has been considered for use in plate fin-tube heat exchangers. The present work describes a numerical investigation about the influence of delta winglet pairs of vortex generators on the flow structure and heat transfer of a plate fin-tube channel. The Navier-Stokes and Energy equations are solved by the finite volume method using a boundary-fitted coordinate system. The influence of vortex generators parameters such as position, angle of attack and aspect ratio were investigated. Local and global influences of vortex generators in heat transfer and flow losses were analyzed by comparison with a model using smooth fin. The results indicate great advantages of this type of geometry for application in plate fin-tube heat exchangers, in terms of large heat transfer enhancement and small pressure loss penalty. (author)

  7. Laminar fluid flow and heat transfer in a fin-tube heat exchanger with vortex generators

    Energy Technology Data Exchange (ETDEWEB)

    Yanagihara, J I; Rodriques, R Jr [Polytechnic School of Univ. of Sao Paolo, Sao Paolo (Brazil). Dept. of Mechanical Engineering

    1997-12-31

    Development of heat transfer enhancement techniques for fin-tube heat exchangers has great importance in industry. In recent years, heat transfer augmentation by vortex generators has been considered for use in plate fin-tube heat exchangers. The present work describes a numerical investigation about the influence of delta winglet pairs of vortex generators on the flow structure and heat transfer of a plate fin-tube channel. The Navier-Stokes and Energy equations are solved by the finite volume method using a boundary-fitted coordinate system. The influence of vortex generators parameters such as position, angle of attack and aspect ratio were investigated. Local and global influences of vortex generators in heat transfer and flow losses were analyzed by comparison with a model using smooth fin. The results indicate great advantages of this type of geometry for application in plate fin-tube heat exchangers, in terms of large heat transfer enhancement and small pressure loss penalty. (author)

  8. Guidelines for generators of hazardous chemical waste at LBL and Guidelines for generators of radioactive and mixed waste at LBL

    International Nuclear Information System (INIS)

    1991-07-01

    The purpose of this document is to provide the acceptance criteria for the transfer of hazardous chemical, radioactive, and mixed waste to Lawrence Berkeley Laboratory's (LBL) Hazardous Waste Handling Facility (HWHF). These guidelines describe how a generator of wastes can meet LBL's acceptance criteria for hazardous chemical, radioactive, and mixed waste. 9 figs

  9. Sorption heat engines: simple inanimate negative entropy generators

    OpenAIRE

    Muller, Anthonie W. J.; Schulze-Makuch, Dirk

    2005-01-01

    The name 'sorption heat engines' is proposed for simple negative entropy generators that are driven by thermal cycling and work on alternating adsorption and desorption. These generators are in general not explicitly recognized as heat engines. Their mechanism is applicable to the fields of engineering, physics, chemistry, geology, and biology, in particular the origin of life. Four kinds of sorption heat engines are distinguished depending on the occurrence of changes in the adsorbent or ads...

  10. Impact of Next Generation District Heating Systems on Distribution Network Heat Losses: A Case Study Approach

    Science.gov (United States)

    Li, Yu; Rezgui, Yacine

    2018-01-01

    District heating (DH) is a promising energy pathway to alleviate environmental negative impacts induced by fossil fuels. Improving the performance of DH systems is one of the major challenges facing its wide adoption. This paper discusses the heat losses of the next generation DH based on the constructed Simulink model. Results show that lower distribution temperature and advanced insulation technology greatly reduce network heat losses. Also, the network heat loss can be further minimized by a reduction of heat demand in buildings.

  11. Thermal resistance of a convectively cooled plate with applied heat flux and variable internal heat generation

    International Nuclear Information System (INIS)

    Venkataraman, N.S.; Cardoso, H.P.; Oliveira Filho, O.B. de

    1981-01-01

    The conductive heat transfer in a rectangular plate with nonuniform internal heat generation, with one end convectively cooled and a part of the opposite end subjected to external heat flux is considered. The remaining part of this end as well as the other two sides are thermally insulated. The governing differential equation is solved by a finite difference scheme. The variation of the thermal resistance with Biot modulus, the plate geometry, the internal heat generation parameter and the type of profile of internal heat generation is discussed. (author) [pt

  12. Heat-Pipe-Associated Localized Thermoelectric Power Generation System

    Science.gov (United States)

    Kim, Pan-Jo; Rhi, Seok-Ho; Lee, Kye-Bock; Hwang, Hyun-Chang; Lee, Ji-Su; Jang, Ju-Chan; Lee, Wook-Hyun; Lee, Ki-Woo

    2014-06-01

    The present study focused on how to improve the maximum power output of a thermoelectric generator (TEG) system and move heat to any suitable space using a TEG associated with a loop thermosyphon (loop-type heat pipe). An experimental study was carried out to investigate the power output, the temperature difference of the thermoelectric module (TEM), and the heat transfer performance associated with the characteristic of the researched heat pipe. Currently, internal combustion engines lose more than 35% of their fuel energy as recyclable heat in the exhaust gas, but it is not easy to recycle waste heat using TEGs because of the limited space in vehicles. There are various advantages to use of TEGs over other power sources, such as the absence of moving parts, a long lifetime, and a compact system configuration. The present study presents a novel TEG concept to transfer heat from the heat source to the sink. This technology can transfer waste heat to any location. This simple and novel design for a TEG can be applied to future hybrid cars. The present TEG system with a heat pipe can transfer heat and generate power of around 1.8 V with T TEM = 58°C. The heat transfer performance of a loop-type heat pipe with various working fluids was investigated, with water at high heat flux (90 W) and 0.05% TiO2 nanofluid at low heat flux (30 W to 70 W) showing the best performance in terms of power generation. The heat pipe can transfer the heat to any location where the TEM is installed.

  13. Gas Generation in Radioactive Wastes - MAGGAS Predictive Life Cycle Model

    International Nuclear Information System (INIS)

    Streatfield, R.E.; Hebditch, D.J.; Swift, B.T.; Hoch, A.R.; Constable, M.

    2006-01-01

    Gases may form from radioactive waste in quantities posing different potential hazards throughout the waste package life cycle. The latter includes surface storage, transport, placing in an operating repository, storage in the repository prior to backfill, closure and the post-closure stage. Potentially hazardous situations involving gas include fire, flood, dropped packages, blocked package vents and disruption to a sealed repository. The MAGGAS (Magnox Gas generation) model was developed to assess gas formation for safety assessments during all stages of the waste package life cycle. This is a requirement of the U.K. regulatory authorities and Nirex and progress in this context is discussed. The processes represented in the model include: Corrosion, microbial degradation, radiolysis, solid-state diffusion, chemico-physical degradation and pressurisation. The calculation was split into three time periods. First the 'aerobic phase' is used to model the periods of surface storage, transport and repository operations including storage in the repository prior to backfill. The second and third periods were designated 'anaerobic phase 1' and 'anaerobic phase 2' and used to model the waste packages in the post-closure phase of the repository. The various significant gas production processes are modeled in each phase. MAGGAS (currently Version 8) is mounted on an Excel spreadsheet for ease of use and speed, has 22 worksheets and is operated routinely for assessing waste packages (e.g. for ventilation of stores and pressurisation of containers). Ten operational and decommissioning generic nuclear power station waste streams were defined as initial inputs, which included ion exchange materials, sludges and concentrates, fuel element debris, graphite debris, activated components, contaminated items, desiccants and catalysts. (authors)

  14. Heat transfer enhancement in cross-flow heat exchanger using vortex generator

    International Nuclear Information System (INIS)

    Yoo, S. Y.; Kwon, H. K.; Kim, B. C.; Park, D. S.; Lee, S. S.

    2003-01-01

    Fouling is very serious problem in heat exchanger because it rapidly deteriorates the performance of heat exchanger. Cross-flow heat exchanger with vortex generators is developed, which enhance heat transfer and reduce fouling. In the present heat exchanger, shell and baffle are removed from the conventional shell-and-tube heat exchanger. The naphthalene sublimation technique is employed to measure the local heat transfer coefficients. The experiments are performed for single circular tube, staggered array tube bank and in-line array tube bank with and without vortex generators. Local and average Nusselt numbers of single tube and tube bank with vortex generator are investigated and compared to those of without vortex generator

  15. Heat generation by a wind turbine

    Energy Technology Data Exchange (ETDEWEB)

    Corten, G.P. [ECN Wind, Petten (Netherlands)

    2001-01-01

    It will be shown that an actuator disk operating in wind turbine mode extracts more energy from the fluid than can be transferred into useful energy. At the Lanchester-Betz limit the decrease of the kinetic energy in the wind is converted by 2 /3 into useful power and by 1 /3 into heat. Behind the wind turbine the outer flow and the flow that has passed the actuator disk will mix. In this process momentum is conserved but part of the kinetic energy will dissipate in heat via viscous shear. 7 refs.

  16. Heat transfer enhanced microwave process for stabilization of liquid radioactive waste slurry. Final report

    International Nuclear Information System (INIS)

    White, T.L.

    1995-01-01

    The objectve of this CRADA is to combine a polymer process for encapsulation of liquid radioactive waste slurry developed by Monolith Technology, Inc. (MTI), with an in-drum microwave process for drying radioactive wastes developed by Oak Ridge National Laboratory (ORNL), for the purpose of achieving a fast, cost-effectve commercial process for solidification of liquid radioactive waste slurry. Tests performed so far show a four-fold increase in process throughput due to the direct microwave heating of the polymer/slurry mixture, compared to conventional edge-heating of the mixer. We measured a steady-state throughput of 33 ml/min for 1.4 kW of absorbed microwave power. The final waste form is a solid monolith with no free liquids and no free particulates

  17. Underground disposal of UK heat-generating wastes: repository design considerations

    International Nuclear Information System (INIS)

    Steadman, J.A.

    1993-12-01

    The report discusses the likely differences in design between a deep repository for disposal of UK heat-generating radioactive wastes and that of the planned Nirex ILW/LLW repository at Sellafield, based on a review of international published information. The main differences arise from the greater heat and radiation outputs of the waste, and in the case of intact PWR spent fuel elements, the greater length and weight of the disposal packages. Published cost estimates for other OECD countries for disposal of heat-generating wastes are considerably lower than that for the UK, partly because in most cases they are for co-disposal with a larger quantity of ILW. (author)

  18. Ocean disposal of heat-generating radioactive waste

    International Nuclear Information System (INIS)

    1987-02-01

    This report addresses the instrumentation of trial penetrators free-falling 6km to embed in ocean floor sediment. The subjects of interest are descent stage behaviour, entry hole location, embedment behaviour and hole closure. Techniques are discussed for measurement of dynamic effects during descent and returning data to the surface. A tape recorder, in a package ejected before embedment, is suggested as a possible means of recovering data. Similar instruments, with solid state memory and acoustical transmission, are suggested for embedment stage measurements. Arrays of seabed transponders are reviewed for measurement of penetrator dynamics, and the consistent location of points of release, entry and rest. An assessment is given of location accuracy. Techniques for the examination of hole closure with on-board instruments are discussed, with reference both to closure during embedment and to closure after embedment. (author)

  19. Ocean disposal of heat generating radioactive waste backfilling requirements

    International Nuclear Information System (INIS)

    1986-07-01

    This report describes the backfilling requirements arising from the disposal of HGW in deep ocean sediments. The two disposal options considered are the drilled emplacement method and the free fall penetrator method. The materials best suited for filling the voids in the two options are reviewed. Candidate materials are selected following a study of the property requirements of each backfill. Placement methods for the candidate materials, as well as the means available for verifying the quality of the filling, are presented. Finally, an assessment of the overall feasibility of each placement method is given. The main conclusion is that, although the proposed methods are feasible, further work is necessary to test in inactive trials each of the proposed filling methods. Moreover, it is difficult to envisage how two of the backfilling operations in drilled emplacement option can be verified by non destructive methods. (author)

  20. Heat diffusion and magnetic field generation

    International Nuclear Information System (INIS)

    Holstein, P.A.

    1983-10-01

    In the report of CECAM workshop in 1982 some results of heat diffusion, when the spontaneous B-field is calculated, have been given. Separately, a similar code (magneto-calo-dynamic or MCD code) has been built and it was interesting to compare them. Comparisom has been made during the workshop of October 1983

  1. Calculation of external exposure during transport and disposal of radioactive waste arisen from dismantling of steam generator

    International Nuclear Information System (INIS)

    Hornacek, M.; Necas, V.

    2014-01-01

    The dismantling of large components (reactor pressure vessel, reactor internals, steam generator) represents complex of processes involving preparation, dismantling, waste treatment and conditioning, transport and final disposal. To optimise all of these activities in accordance with the ALARA principle the prediction of the exposure of workers is an essential prerequisite. The paper deals with the calculation of external exposure of workers during transport and final disposal of heat exchange tubes of steam generator used in Slovak nuclear power plant V1 in Jaslovske Bohunice. The type of waste packages, the calculation models of truck and National Radioactive Waste Repository in Mochovce are presented. The detailed methodology of radioactive waste disposal is showed and the degree of influence of time decay (0, 5 and 10 years) on the radiological conditions during transport and disposal is studied. All of the results do not exceed the limits given in Slovak and international regulatory documents. (authors)

  2. Glas generator for the steam gasification of coal with nuclear generated heat

    International Nuclear Information System (INIS)

    Buchner, G.

    1980-01-01

    The use of heat from a High Temperature Reactor (HTR) for the steam gasification of coal saves coal, which otherwise is burnt to generate the necessary reaction heat. The gas generator for this process, a horizontal pressure vessel, contains a fluidized bed of coal and steam. An ''immersion-heater'' type of heat exchanger introduces the nuclear generated heat to the process. Some special design problems of this gasifier are presented. Reference is made to the present state of development of the steam gasification process with heat from high temperature reactors. (author)

  3. Report on the disposal of radioactive wastes and spent fuel elements from Baden-Wuerttemberg

    International Nuclear Information System (INIS)

    2017-04-01

    The report on the disposal of radioactive wastes and spent fuel elements from Baden- Wuerttemberg covers the following issues: legal framework for the nuclear disposal; producer of spent fuels and radioactive wastes in Baden- Report on the disposal of radioactive wastes and spent fuel elements from Baden- Wuerttemberg; low- and medium-level radioactive wastes (non heat generating radioactive wastes); spent fuels and radioactive wastes from waste processing (heat generating radioactive wastes); final disposal.

  4. Methodology of site generation for evaluation of the behaviour of radioactive waste storage

    International Nuclear Information System (INIS)

    Ruiz Rivas, C.; Eguilior Diez, S.

    1997-01-01

    The present report summarizes the purpose of methodology for the site generation in the evaluation of high-level radioactive waste storage for long-term. This work is developed into the project Safety analysis long-term of high-level radioactive waste. This project is carried on for CIEMAT and ENRESA

  5. Management of radioactive waste generated from nuclear power reactors in Korea

    International Nuclear Information System (INIS)

    Jeong-Mook Kim

    2000-01-01

    Fundamental objectives and efforts to safely manage radioactive wastes generating from the expanding nuclear power industry in the Republic of Korea are described. Management, treatment and storage of radioactive wastes arising in different form are addressed. A long tern plan to reduce the volume of solid waste is outlined. (author)

  6. Users manual. Pursuit program of use licenses of radioactive material or generator equipment of ionizing radiations

    International Nuclear Information System (INIS)

    Becerril M, V.M.; Villarreal, J.E.

    1992-05-01

    The objective of the program 'Databases for the pursuit of licenses of use of radioactive material', it consists on the application of a computer system carried out in dbase IV that it allows the control of the all the information related with those licenses for use, possession and storage of radioactive material or generator equipment of ionizing radiations. (Author)

  7. Thermodynamic analysis of waste heat power generation system

    International Nuclear Information System (INIS)

    Guo, Jiangfeng; Xu, Mingtian; Cheng, Lin

    2010-01-01

    In the present work, a waste heat power generation system is analyzed based on the criteria with and without considering the heat/exergy loss to the environment. For the criteria without considering the heat/exergy loss to the environment, the first- and second-law efficiencies display different tendencies with the variations of some system parameters. When the heat/exergy loss to the environment is taken into consideration, the first and second law efficiencies display the same tendency. Thus, choosing the appropriate expressions for the performance criteria is crucial for the optimization design of the waste heat power generation system. It is found that there are two approaches to improving the system performance: one is to improve the heat/exergy input; the other is to enhance the heat-work conversion ability of the system. The former would deteriorate the environment if the heat-work conversion ability of the system remains unchanged; the latter could reduce the environmental impact but it's restricted by the heat/exergy input. Therefore, the optimal operation condition should be achieved at the trade-off between the heat/exergy input and the heat-work conversion ability of the system.

  8. Radioactive waste generation in the nuclear reactors in Romania

    International Nuclear Information System (INIS)

    Popescu, I.V.

    2002-01-01

    The successful use of nuclear fission as major source of energy for this century is based upon the technological capabilities acquired to face the issue of radioactive waste and spent fuel. The management of radioactive waste is complex and implies solving the following major problems: - isolation of the radioisotopes from the complex of effluents released in the environment; - processing the separated radioisotopes for subsequent storing and final disposal; - transport of processed and conditioned wastes towards disposal repository; - selecting the sites for storage and final disposal. During reactor operation liquid and gaseous effluents are released to the environment as well as radioactive materials. All these may have an dangerous impact upon the environment when the international regulations, i.e. the ALARA principle are not strictly observed. The maximal values for the radioactive release are established by national regulations which are concordant with the IAEA principles. The amount of radioactive materials released depends of the reactor type and the measures adopted to reduce these releases. The average values of these releases during the normal operation of the reactor constitute the 'source term'. Its calculation implies several factors such as: the reactor type; the radionuclide concentration in the primary cooling systems; the transport mechanisms and leaks resulting in liquid and gaseous radionuclide emissions; the efficiency of the barriers and engineered safety systems built to reduce the amounts of radionuclide in the effluents. The concentration of radionuclides in the primary cooling circuit depends on the reactor power level, fuel burnup, fuel sheath type, tightness of the fuel cans, impurity concentration, chemical additives in the fluid of the primary cooling system, the total volume of this fluid, as well as its purification system. The methods applied to facilitate the calculation of the source term are described. In 1998 the spent fuel

  9. RESEARCH OF HYDRODYNAMICS OF HEAT GENERATORS FOR MECHANICAL SYSTEMS AUTONOMOUS HEATING

    Directory of Open Access Journals (Sweden)

    E. M. Derbasova

    2014-01-01

    Full Text Available A design of mechanical heat source, allows direct conversion of mechanical energy of the wind flow into thermal energy due to friction forces in a highly viscous fluid. Obtained theoretical dependence for calculating the heat generated by converting mechanical energy into heat. For laminar flow of a highly viscous, fluid in the gap between the stationary and rotating disk heat source. Based on experimental studies to determine the average thickness of the boundary layer between the rotating and fixed disks. The dependences to identify key structural dimensions of mechanical heat sources for heating systems. 

  10. Creeping Viscous Flow around a Heat-Generating Solid Sphere

    DEFF Research Database (Denmark)

    Krenk, Steen

    1981-01-01

    The velocity field for creeping viscous flow around a solid sphere due to a spherically symmetric thermal field is determined and a simple thermal generalization of Stokes' formula is obtained. The velocity field due to an instantaneous heat source at the center of the sphere is obtained in closed...... form and an application to the storage of heat-generating nuclear waste is discussed....

  11. Optimization of the Heat Exchangers of a Thermoelectric Generation System

    Science.gov (United States)

    Martínez, A.; Vián, J. G.; Astrain, D.; Rodríguez, A.; Berrio, I.

    2010-09-01

    The thermal resistances of the heat exchangers have a strong influence on the electric power produced by a thermoelectric generator. In this work, the heat exchangers of a thermoelectric generator have been optimized in order to maximize the electric power generated. This thermoelectric generator harnesses heat from the exhaust gas of a domestic gas boiler. Statistical design of experiments was used to assess the influence of five factors on both the electric power generated and the pressure drop in the chimney: height of the generator, number of modules per meter of generator height, length of the fins of the hot-side heat exchanger (HSHE), length of the gap between fins of the HSHE, and base thickness of the HSHE. The electric power has been calculated using a computational model, whereas Fluent computational fluid dynamics (CFD) has been used to obtain the thermal resistances of the heat exchangers and the pressure drop. Finally, the thermoelectric generator has been optimized, taking into account the restrictions on the pressure drop.

  12. The concept of responsibility to future generations for the management and storage of radioactive waste

    International Nuclear Information System (INIS)

    Vial, E.

    2004-01-01

    Recognition of the concept of responsibility to future generations seems, to imply the need to assume responsibility today for radioactive waste legacy of the past as well as for the waste that is currently being generated. However, this view of things, or more precisely this interpretation, is clouded by the lack of a clear definition of the concept of responsibility towards future generations. The concept has been used mainly in connection with long-lived radioactive wastes, which pose the greatest management problem as it so so far exceeds any human scale of reference. Consideration for future generations has to be a factor in the management of all types of radioactive waste, be it short, medium or long-lived waste or very low, low, intermediate or highly radioactive waste. As a general rule the concept of responsibility has made focus on long lived waste, whatever its level of radioactivity. The current alternatives for the management of radioactive waste may be: interim storage, final disposal, incineration, transmutation, to lower the radioactivity of the wastes. These different alternatives are discussed because they are not all genuine solutions and need to be deepened. (N.C.)

  13. Gas Generation of Heated PBX 9502

    Energy Technology Data Exchange (ETDEWEB)

    Holmes, Matthew David [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Parker, Gary Robert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-10-07

    Uniaxially pressed samples of PBX 9502 were heated until self-ignition (cookoff) in order to collect pressure and temperature data relevant for model development. Samples were sealed inside a small gas-tight vessel, but were mechanically unconfined. Long-duration static pressure rise, as well as dynamic pressure rise during the cookoff event, were recorded. Time-lapse photography of the sample was used to measure the thermal expansion of the sample as a function of time and temperature. High-speed videography qualitatively characterized the mechanical behavior and failure mechanisms at the time of cookoff. These results provide valuable input to modeling efforts, in order to improve the ability to predict pressure output during cookoff as well as the effect of pressure on time-toignition.

  14. Guidelines for generators of hazardous chemical waste at LBL and guidelines for generators of radioactive and mixed waste at LBL

    International Nuclear Information System (INIS)

    1991-09-01

    In part one of this document the Governing Documents and Definitions sections provide general guidelines and regulations applying to the handling of hazardous chemical wastes. The remaining sections provide details on how you can prepare your waste properly for transport and disposal. They are correlated with the steps you must take to properly prepare your waste for pickup. The purpose of the second part of this document is to provide the acceptance criteria for the transfer of radioactive and mixed waste to LBL's Hazardous Waste Handling Facility (HWHF). These guidelines describe how you, as a generator of radioactive or mixed waste, can meet LBL's acceptance criteria for radioactive and mixed waste

  15. Heat flow and radioactivity studies in the Ross Island-dry valley area, Antarctica and their tectonic implications

    International Nuclear Information System (INIS)

    Bucher, G.J.

    1980-01-01

    In conjunction with the Dry Valley Drilling Project, the University of Wyoming conducted heat flow and basement radioactivity studies in the Ross Island-dry valley area of southern Victoria Land, Antarctica. This part of Antarctica is characterized by late Cenozoic alkaline basaltic volcanism and uplift. Six heat flow (q) values for the area range from 1.4 to 2.0 HFU, with a mean value of 1.7 HFU. Radioactive heat production (A) values for basement rocks from the dry valleys range from 2.2 to 4.1 HGU, with a mean value of 3.0 HGU. The combined q-A data imply that this area is a zone of high reduced heat flow, similar to the Basin and Range province in the western United States and other zones of late Cenozoic tectonof Antarctica is probably in the range of 1.2 to 1.6 HFU, which is about 50 to 100% higher than the reduced flux which characterizes stable continental areas. The results of the transient conductive models presented herein imply that the high flux in this part of Antarctica cannot be explained by the residual thermal effects of a major episode of lithospheric thinning associated with the generation of the Ferrar Dolerites. The correlation between steady conductive thermal models and the late Cenozoic, silica-undersaturated, alkaline basalts of the region is similarly obscure. For example, purely conductive steady-state temperature-depth models predict partial melting at depths of only 45 to 50 km in the mantle, whereas geochemical data for the volcanic units are consistent with the basalts being generated at depths of at least 60 to 80 km

  16. Heat transfer analyses for grout disposal of radioactive double-shell slurry and customer wastes

    International Nuclear Information System (INIS)

    Robinson, S.M.; Gilliam, T.M.; McDaniel, E.W.

    1987-04-01

    Grout immobilization is being considered by Rockwell Hanford Operations (Rockwell Hanford) as a permanent disposal method for several radioactive waste streams. These include disposal of customer and double-shell slurry wastes in earthen trenches and in single-shell underground waste storage tanks. Heat transfer studies have previously been made to determine the maximum heat loading for grout disposal of various wastes under similar conditions, but a sensitivity analysis of temperature profiles to input parameters was needed. This document presents the results of heat transfer calculations for trenches containing grouted customer and double-shell slurry wastes and for in situ disposal of double-shell wastes in single-shell, domed concrete storage tanks. It discusses the conditions that lead to maximum grout temperatures of 250 0 F during the curing stage and 350 0 F thereafter and shows the dependence of these temperatures on input parameters such as soil and grout thermal conductivity, grout specific heat, waste loading, and disposal geometries. Transient heat transfer calculations were made using the HEATING6 computer code to predict temperature profiles in solidified low-level radioactive waste disposal scenarios at the Rockwell Hanford site. The calculations provide guidance for the development of safe, environmentally acceptable grout formulas for the Transportable Grout Facility. 11 refs

  17. Heat generation: prices have only a minor influence

    International Nuclear Information System (INIS)

    Stadelmann, M.

    2006-01-01

    This article takes a look at long-term trends in the heat generation market. Here, heat-pumps, gas heaters and wood-fired systems, together with their combination with solar collectors, are gaining ground, whereas heating oil is loosing its share of the market. The various influences on the market and, in particular, price increases for oil are discussed. The influence of revised energy legislation is discussed, which calls for 20% of the standardised energy requirements of housing to be met by renewables or increased thermal insulation. Increased sales in the solar sector are discussed, as are future trends in the heating market

  18. Natural convection in porous media with heat generation

    International Nuclear Information System (INIS)

    Hardee, H.C. Jr.; Nilson, R.H.

    1976-12-01

    Heat transfer characteristics of a fluid saturated porous media are investigated for the case of uniform internal heat generation with cooling from above. Analytical models of conduction and single phase cellular convection show good agreement with previous Rayleigh number correlations and with experimental data obtained by Joule heating of salt water in a sand bed. An approximate dryout criterion is also derived for two phase boiling heat transfer in a fixed bed which is neither channeled nor fluidized. Correlation of dryout data using this criterion is encouraging, especially considering the analytical rather than correlational basis of the criterion

  19. Heating unit of Berovo by co-generation (Macedonia)

    International Nuclear Information System (INIS)

    Armenski, Slave; Dimitrov, Konstantin; Tashevski, Done

    1999-01-01

    A plant for combined heat and electric power production, for central heating of the town Berovo (Macedonia) is proposed. The common reason to use a co-generation unit is the energy efficiency and a significant reduction of environmental pollution. The heat consumption of town Berovo is analyzed and determined. Based on the energy consumption of a whole power plant, e. i. the plant for combined and simultaneous production of power is proposed. The quantity of annually heat and electrical production and annually coal consumption are estimated. (Author)

  20. Heat savings in energy systems with substantial distributed generation

    DEFF Research Database (Denmark)

    Østergaard, PA

    2003-01-01

    In Denmark, the integration of wind power is affected by a large amount of cogeneration of heat and power. With ancillary services supplied by large-scale condensation and combined heat and power (CHP) plants, a certain degree of large-scale generation is required regardless of momentary wind input......, if a certain production is required regardless of whether over-all electricity generation is sufficient. This article analyses this and although heat savings do have a negative impact on the amount of wind power the system may integrate a given moment in certain cases, associated fuel savings are notable...

  1. Distributed Generation with Heat Recovery and Storage

    OpenAIRE

    Siddiqui, Afzal; Marnay, Chris; Firestone, Ryan M.; Zhou, Nan

    2005-01-01

    Electricity produced by distributed energy resources (DER) located close to end-use loads has the potential to meet consumer requirements more efficiently than the existing centralized grid. Installation of DER allows consumers to circumvent the costs associated with transmission congestion and other non-energy costs of electricity delivery and potentially to take advantage of market opportunities to purchase energy when attractive. On-site, single-cycle thermal power generation is typic...

  2. Characteristics of radioactive waste streams generated in HTGR fuel reprocessing

    International Nuclear Information System (INIS)

    Lin, K.H.

    1976-01-01

    Results are presented of a study concerned with identification and characterization of radioactive waste streams from an HTGR fuel reprocessing plant. Approximate quantities of individual waste streams as well as pertinent characteristics of selected streams have been estimated. Most of the waste streams are unique to HTGR fuel reprocessing. However, waste streams from the solvent extraction system and from the plant facilities do not differ greatly from the corresponding LWR fuel reprocessing wastes

  3. Passive flow heat exchanger simulation for power generation from solar pond using thermoelectric generators

    Science.gov (United States)

    Baharin, Nuraida'Aadilia; Arzami, Amir Afiq; Singh, Baljit; Remeli, Muhammad Fairuz; Tan, Lippong; Oberoi, Amandeep

    2017-04-01

    In this study, a thermoelectric generator heat exchanger system was designed and simulated for electricity generation from solar pond. A thermoelectric generator heat exchanger was studied by using Computational Fluid Dynamics to simulate flow and heat transfer. A thermoelectric generator heat exchanger designed for passive in-pond flow used in solar pond for electrical power generation. A simple analysis simulation was developed to obtain the amount of electricity generated at different conditions for hot temperatures of a solar pond at different flow rates. Results indicated that the system is capable of producing electricity. This study and design provides an alternative way to generate electricity from solar pond in tropical countries like Malaysia for possible renewable energy applications.

  4. Smart energy systems and 4th generation district heating

    DEFF Research Database (Denmark)

    Lund, Henrik; Duic, Neven; Østergaard, Poul Alberg

    2016-01-01

    scientific understanding on how we can design and implement a suitable and least-cost transformation into a sustainable energy future. The concept of Smart Energy Systems emphasizes the importance of being coherent and cross-sectoral when the best solutions are to be found and how this also calls......This editorial gives an introduction to the important relationship between Smart Energy Systems and 4th Generation District Heating and presents a number of selected papers from the 1st International Conference on the topic. All of the papers elaborate on or otherwise contribute to the theoretical...... for the active inclusion of the heating and cooling sectors. The concept of 4th Generation District Heating emphasizes that district heating and cooling are both important elements but also technologies that have to be developed further into a 4th generation version to be able to fulfil their roles in future...

  5. District heating and co-generation in Slovenia

    International Nuclear Information System (INIS)

    Hrovatin, Franc; Pecaric, Marko; Perovic, Olgica

    2000-01-01

    Recent development of district heating systems, gasification and co-generation processes in local communities in Slovenia as well as current status, potentials, possibilities and plans for further development in this sphere are presented. The current status presents energy production, distribution and use in district heating systems and in local gas distribution networks. An analysis of the energy and power generated and distributed in district power systems, made with regard to the size of the system, fuel used, type of consumers and the way of production, is given. Growth in different areas of local power systems in the period of last years is included. Potentials in the sphere of electrical energy and heat co-generation were assessed. Some possibilities and experience in heat energy storage are given and trends and plans for further development are introduced. (Authors)

  6. National need for utilizing nuclear energy for process heat generation

    International Nuclear Information System (INIS)

    Gambill, W.R.; Kasten, P.R.

    1984-01-01

    Nuclear reactors are potential sources for generating process heat, and their applications for such use economically competitive. They help satisfy national needs by helping conserve and extend oil and natural gas resources, thus reducing energy imports and easing future international energy concerns. Several reactor types can be utilized for generating nuclear process heat; those considered here are light water reactors (LWRs), heavy water reactors (HWRs), gas-cooled reactors (GCRs), and liquid metal reactors (LMRs). LWRs and HWRs can generate process heat up to 280 0 C, LMRs up to 540 0 C, and GCRs up to 950 0 C. Based on the studies considered here, the estimated process heat markets and the associated energy markets which would be supplied by the various reactor types are summarized

  7. Disposal facility for radioactive wastes

    International Nuclear Information System (INIS)

    Utsunomiya, Toru.

    1985-01-01

    Purpose: To remove heat generated from radioactive wastes thereby prevent the working circumstances from being worsened in a disposal-facility for radioactive wastes. Constitution: The disposal-facility comprises a plurality of holes dug out into the ground inside a tunnel excavated for the storage of radioactive wastes. After placing radioactive wastes into the shafts, re-filling materials are directly filled with a purpose of reducing the dosage. Further, a plurality of heat pipes are inserted into the holes and embedded within the re-filling materials so as to gather heat from the radioactive wastes. The heat pipes are connected to a heat exchanger disposed within the tunnel. As a result, heating of the solidified radioactive wastes itself or the containing vessel to high temperature can be avoided, as well as thermal degradation of the re-filling materials and the worsening in the working circumstance within the tunnel can be overcome. (Moriyama, K.)

  8. Method to determine the radioactivity of radioactive waste packages. Basic procedure of the method used to determine the radioactivity of low-level radioactive waste packages generated at nuclear power plants: 2007

    International Nuclear Information System (INIS)

    2008-03-01

    This document describes the procedures adopted in order to determine the radioactivity of low-level radioactive waste packages generated at nuclear power plants in Japan. The standards applied have been approved by the Atomic Energy Society of Japan after deliberations by the Subcommittee on the Radioactivity Verification Method for Waste Packages, the Nuclear Cycle Technical Committee, and the Standards Committee. The method for determining the radioactivity of the low-level radioactive waste packages was based on procedures approved by the Nuclear Safety Commission in 1992. The scaling factor method and other methods of determining radioactivity were then developed on the basis of various investigations conducted, drawing on extensive accumulated knowledge. Moreover, the international standards applied as common guidelines for the scaling factor method were developed by Technical Committee ISO/TC 85, Nuclear Energy, Subcommittee SC 5, Nuclear Fuel Technology. Since the application of accumulated knowledge to future radioactive waste disposal is considered to be rational and justified, such body of knowledge has been documented in a standardized form. The background to this standardization effort, the reasoning behind the determination method as applied to the measurement of radioactivity, as well as other related information, are given in the Annexes hereto. This document includes the following Annexes. Annex 1: (reference) Recorded items related to the determination of the scaling factor. Annex 2 (reference): Principles applied to the determining the radioactivity of waste packages. (author)

  9. Heat Transfer and Entropy Generation Analysis of an Intermediate Heat Exchanger in ADS

    Science.gov (United States)

    Wang, Yongwei; Huai, Xiulan

    2018-04-01

    The intermediate heat exchanger for enhancement heat transfer is the important equipment in the usage of nuclear energy. In the present work, heat transfer and entropy generation of an intermediate heat exchanger (IHX) in the accelerator driven subcritical system (ADS) are investigated experimentally. The variation of entropy generation number with performance parameters of the IHX is analyzed, and effects of inlet conditions of the IHX on entropy generation number and heat transfer are discussed. Compared with the results at two working conditions of the constant mass flow rates of liquid lead-bismuth eutectic (LBE) and helium gas, the total pumping power all tends to reduce with the decreasing entropy generation number, but the variations of the effectiveness, number of transfer units and thermal capacity rate ratio are inconsistent, and need to analyze respectively. With the increasing inlet mass flow rate or LBE inlet temperature, the entropy generation number increases and the heat transfer is enhanced, while the opposite trend occurs with the increasing helium gas inlet temperature. The further study is necessary for obtaining the optimized operation parameters of the IHX to minimize entropy generation and enhance heat transfer.

  10. Cogeneration using a nuclear reactor to generate process heat

    International Nuclear Information System (INIS)

    Alonso, Gustavo; Ramirez, Ramon

    2009-01-01

    Some of the new nuclear reactor technologies (Generation III+) are claiming the production of process heat as an additional value to electricity generation. These technologies are still under development and none of them has shown how this can be possible and what will be the penalty in electricity generation to have this additional product. The current study assess the likeliness of generate process heat from a Pebble Bed Modular Reactor to be used for a refinery showing different plant balance and alternatives to produce and use that process heat. An actual practical example is presented to demonstrate the cogeneration viability using the fact that the PBMR is a modular small reactor and also the challenges that this option has. (author)

  11. Study of entropy generation in a slab with non-uniform internal heat generation

    Directory of Open Access Journals (Sweden)

    El Haj Assad Mamdouh

    2013-01-01

    Full Text Available Analysis of entropy generation in a rectangular slab with a nonuniform internal heat generation is presented. Dimensionless local and total entropy generation during steady state heat conduction through the slab are obtained. Two different boundary conditions have been considered in the analysis, the first with asymmetric convection and the second with constant slab surface temperature. Temperature distribution within the slab is obtained analytically. The study investigates the effect of some relevant dimensionless heat transfer parameters on entropy generation. The results show that there exists a minimum local entropy generation but there does not exist a minimum total entropy generation for certain combinations of the heat transfer parameters. The results of calculations are presented graphically.

  12. Sustainability assessment of renewable power and heat generation technologies

    International Nuclear Information System (INIS)

    Dombi, Mihály; Kuti, István; Balogh, Péter

    2014-01-01

    Rationalisation of consumption, more efficient energy usage and a new energy structure are needed to be achieved in order to shift the structure of energy system towards sustainability. The required energy system is among others characterised by intensive utilisation of renewable energy sources (RES). RES technologies have their own advantages and disadvantages. Nevertheless, for the strategic planning there is a great demand for the comparison of RES technologies. Furthermore, there are additional functions of RES utilisation expected beyond climate change mitigation, e.g. increment of employment, economic growth and rural development. The aim of the study was to reveal the most beneficial RES technologies with special respect to sustainability. Ten technologies of power generation and seven technologies of heat supply were examined in a multi-criteria sustainability assessment frame of seven attributes which were evaluated based on a choice experiment (CE) survey. According to experts the most important characteristics of RES utilisation technologies are land demand and social impacts i.e. increase in employment and local income generation. Concentrated solar power (CSP), hydropower and geothermal power plants are favourable technologies for power generation, while geothermal district heating, pellet-based non-grid heating and solar thermal heating can offer significant advantages in case of heat supply. - highlights: • We used choice experiment to estimate the weights of criteria for the sustainability assessment of RES technologies. • The most important attributes of RES technologies according to experts are land demand and social impacts. • Concentrated solar power (CSP), hydropower and geothermal power plants are advantageous technologies for power generation. • Geothermal district heating, pellet-based non-grid heating and solar thermal heating are favourable in case of heat supply

  13. Heat generated by dental implant drills during osteotomy-a review: heat generated by dental implant drills.

    Science.gov (United States)

    Mishra, Sunil Kumar; Chowdhary, Ramesh

    2014-06-01

    Osseointegration is the more stable situation and results in a high success rate of dental implants. Heat generation during rotary cutting is one of the important factors influencing the development of osseointegration. To assess the various factors related to implant drills responsible for heat generation during osteotomy. To identify suitable literature, an electronic search was performed using Medline and Pubmed database. Articles published in between 1960 to February 2013 were searched. The search is focused on heat generated by dental implant drills during osteotomy. Various factors related to implant drill such effect of number of blades; drill design, drill fatigue, drill speed and force applied during osteotomies which were responsible for heat generation were reviewed. Titles and abstracts were screened, and literature that fulfilled the inclusion criteria was selected for a full-text reading. The initial literature search resulted in 299 articles out of which only 70 articles fulfils the inclusion criteria and were included in this systematic review. Many factors related to implant drill responsible for heat generation were found. Successful preparation of an implant cavity with minimal damage to the surrounding bone depends on the avoidance of excessive temperature generation during surgical drilling. The relationship between heat generated and implant drilling osteotomy is multifactorial in nature and its complexity has not been fully studied. Lack of scientific knowledge regarding this issue still exists. Further studies should be conducted to determine the various factors which generate less heat while osteotomy such as ideal ratio of force and speed in vivo, exact time to replace a drill, ideal drill design, irrigation system, drill-bone contact area.

  14. Approaches to the final storage of radioactive waste in the Federal Republic of Germany. Will responsibility be shifted to future generations?

    International Nuclear Information System (INIS)

    Thomauske, B.

    2004-01-01

    With respect to the management of high-level radioactive waste in Germany, there is agreement on these premises: - The waste is to be stored permanently in the Federal Republic of Germany. - A repository is to be operational by 2030. - Final storage is to be achieved in geologic formations. Differences of opinion exist about these questions: - Should there be only one repository for all types of radioactive waste, or would a breakdown into waste generating heat and waste generating only negligible amounts of heat in different repositories be useful under aspects of safety and requirement? - Will a new site selection procedure be required in an effort to find a suitable site, and would such a selection procedure be able to meet the deadline of 2030 for an operational repository? - After the end of legal proceedings, should the Konrad repository be revamped for waste generating negligible amounts of heat? The analysis presented shows that an operational repository for waste generating heat can be made available only in connection with continued exploration work at Gorleben and demonstration of the suitability of that site and subsequent construction of the repository. If the search for a repository site were started from scratch, the date of commissioning such a facility would be after 2050. In this way, that approach would miss the purpose of not shifting the waste management issue to future generations. Acting responsibly means to build the Konrad repository speedily after completion of the legal proceedings about a permit and, in this way, avoid the addition of more interim stores for waste generating negligible amounts of heat. Further exploration of Gorleben is the way agreed upon and necessary for the creation of a repository for high-level radioactive waste generating heat by 2030. For this purpose, the 'points of doubt' must be resolved speedily. (orig.) [de

  15. Entropy generation of nanofluid flow in a microchannel heat sink

    Science.gov (United States)

    Manay, Eyuphan; Akyürek, Eda Feyza; Sahin, Bayram

    2018-06-01

    Present study aims to investigate the effects of the presence of nano sized TiO2 particles in the base fluid on entropy generation rate in a microchannel heat sink. Pure water was chosen as base fluid, and TiO2 particles were suspended into the pure water in five different particle volume fractions of 0.25%, 0.5%, 1.0%, 1.5% and 2.0%. Under laminar, steady state flow and constant heat flux boundary conditions, thermal, frictional, total entropy generation rates and entropy generation number ratios of nanofluids were experimentally analyzed in microchannel flow for different channel heights of 200 μm, 300 μm, 400 μm and 500 μm. It was observed that frictional and total entropy generation rates increased as thermal entropy generation rate were decreasing with an increase in particle volume fraction. In microchannel flows, thermal entropy generation could be neglected due to its too low rate smaller than 1.10e-07 in total entropy generation. Higher channel heights caused higher thermal entropy generation rates, and increasing channel height yielded an increase from 30% to 52% in thermal entropy generation. When channel height decreased, an increase of 66%-98% in frictional entropy generation was obtained. Adding TiO2 nanoparticles into the base fluid caused thermal entropy generation to decrease about 1.8%-32.4%, frictional entropy generation to increase about 3.3%-21.6%.

  16. Heat Pipe-Assisted Thermoelectric Power Generation Technology for Waste Heat Recovery

    Science.gov (United States)

    Jang, Ju-Chan; Chi, Ri-Guang; Rhi, Seok-Ho; Lee, Kye-Bock; Hwang, Hyun-Chang; Lee, Ji-Su; Lee, Wook-Hyun

    2015-06-01

    Currently, large amounts of thermal energy dissipated from automobiles are emitted through hot exhaust pipes. This has resulted in the need for a new efficient recycling method to recover energy from waste hot exhaust gas. The present experimental study investigated how to improve the power output of a thermoelectric generator (TEG) system assisted by a wickless loop heat pipe (loop thermosyphon) under the limited space of the exhaust gas pipeline. The present study shows a novel loop-type heat pipe-assisted TEG concept to be applied to hybrid vehicles. The operating temperature of a TEG's hot side surface should be as high as possible to maximize the Seebeck effect. The present study shows a novel TEG concept of transferring heat from the source to the sink. This technology can transfer waste heat to any local place with a loop-type heat pipe. The present TEG system with a heat pipe can transfer heat and generate an electromotive force power of around 1.3 V in the case of 170°C hot exhaust gas. Two thermoelectric modules (TEMs) for a conductive block model and four Bi2Te3 TEMs with a heat pipe-assisted model were installed in the condenser section. Heat flows to the condenser section from the evaporator section connected to the exhaust pipe. This novel TEG system with a heat pipe can be placed in any location on an automobile.

  17. Possible generation of heat from nuclear fusion in Earth's inner core.

    Science.gov (United States)

    Fukuhara, Mikio

    2016-11-23

    The cause and source of the heat released from Earth's interior have not yet been determined. Some research groups have proposed that the heat is supplied by radioactive decay or by a nuclear georeactor. Here we postulate that the generation of heat is the result of three-body nuclear fusion of deuterons confined in hexagonal FeDx core-centre crystals; the reaction rate is enhanced by the combined attraction effects of high-pressure (~364 GPa) and high-temperature (~5700 K) and by the physical catalysis of neutral pions: 2 D +  2 D +  2 D → 2 1 H +  4 He + 2  + 20.85 MeV. The possible heat generation rate can be calculated as 8.12 × 10 12  J/m 3 , based on the assumption that Earth's primitive heat supply has already been exhausted. The H and He atoms produced and the anti-neutrino are incorporated as Fe-H based alloys in the H-rich portion of inner core, are released from Earth's interior to the universe, and pass through Earth, respectively.

  18. Incineration of hazardous and low-level radioactive waste by a small generator. Final report

    International Nuclear Information System (INIS)

    Dwight, C.C.

    1984-10-01

    The results from Arizona State University's study of the feasibility of a small generator incinerating low-level radioactive waste in a pathological incinerator are reported. The research included various aspects of environmental impact, public relations, cost versus benefit, and licensing procedures. Three years of work resulted in a license amendment authorizing the University to incinerate certain hazardous and low-level radioactive wastes. 13 references, 6 figures, 16 tables

  19. Flow visualization in heat-generating porous media

    International Nuclear Information System (INIS)

    Lee, D.O.; Nilson, R.H.

    1977-11-01

    The work reported is in support of the Sandia Post-Accident Heat Removal Program, in which simulated LMFBR beds will be subjected to in-pile heating in the ACPR (Annular Core Pulsed Reactor). Flow visualization experiments were performed to gain some insight into the flow patterns and temperature distributions in a fluid-saturated heat-generating porous medium. Although much of the information presented is of a qualitative nature, it is useful in the recognition of the controlling transport process and in the formulation of analytic and numerical models

  20. Effective thermal conductivity of a heat generating rod bundle dissipating heat by natural convection and radiation

    International Nuclear Information System (INIS)

    Senve, Vinay; Narasimham, G.S.V.L.

    2011-01-01

    Highlights: → Transport processes in isothermal hexagonal sheath with 19 heat generating rods is studied. → Correlation is given to predict the maximum temperature considering all transport processes. → Effective thermal conductivity of rod bundle can be obtained using max temperature. → Data on the critical Rayleigh numbers for p/d ratios of 1.1-2.0 is presented. → Radiative heat transfer contributes to heat dissipation of 38-65% of total heat. - Abstract: A numerical study of conjugate natural convection and surface radiation in a horizontal hexagonal sheath housing 19 solid heat generating rods with cladding and argon as the fill gas, is performed. The natural convection in the sheath is driven by the volumetric heat generation in the solid rods. The problem is solved using the FLUENT CFD code. A correlation is obtained to predict the maximum temperature in the rod bundle for different pitch-to-diameter ratios and heat generating rates. The effective thermal conductivity is related to the heat generation rate, maximum temperature and the sheath temperature. Results are presented for the dimensionless maximum temperature, Rayleigh number and the contribution of radiation with changing emissivity, total wattage and the pitch-to-diameter ratio. In the simulation of a larger system that contains a rod bundle, the effective thermal conductivity facilitates simplified modelling of the rod bundle by treating it as a solid of effective thermal conductivity. The parametric studies revealed that the contribution of radiation can be 38-65% of the total heat generation, for the parameter ranges chosen. Data for critical Rayleigh number above which natural convection comes into effect is also presented.

  1. Particle size of radioactive aerosols generated during machine operation in high-energy proton accelerators

    International Nuclear Information System (INIS)

    Oki, Yuichi; Kanda, Yukio; Kondo, Kenjiro; Endo, Akira

    2000-01-01

    In high-energy accelerators, non-radioactive aerosols are abundantly generated due to high radiation doses during machine operation. Under such a condition, radioactive atoms, which are produced through various nuclear reactions in the air of accelerator tunnels, form radioactive aerosols. These aerosols might be inhaled by workers who enter the tunnel just after the beam stop. Their particle size is very important information for estimation of internal exposure doses. In this work, focusing on typical radionuclides such as 7 Be and 24 Na, their particle size distributions are studied. An aluminum chamber was placed in the EP2 beam line of the 12-GeV proton synchrotron at High Energy Accelerator Research Organization (KEK). Aerosol-free air was introduced to the chamber, and aerosols formed in the chamber were sampled during machine operation. A screen-type diffusion battery was employed in the aerosol-size analysis. Assuming that the aerosols have log-normal size distributions, their size distributions were obtained from the radioactivity concentrations at the entrance and exit of the diffusion battery. Radioactivity of the aerosols was measured with Ge detector system, and concentrations of non-radioactive aerosols were obtained using condensation particle counter (CPC). The aerosol size (radius) for 7 Be and 24 Na was found to be 0.01-0.04 μm, and was always larger than that for non-radioactive aerosols. The concentration of non-radioactive aerosols was found to be 10 6 - 10 7 particles/cm 3 . The size for radioactive aerosols was much smaller than ordinary atmospheric aerosols. Internal doses due to inhalation of the radioactive aerosols were estimated, based on the respiratory tract model of ICRP Pub. 66. (author)

  2. Heat transfer of liquid-metal magnetohydrodynamic flow with internal heat generation

    International Nuclear Information System (INIS)

    Kumamaru, Hiroshige; Kurita, Kazuhisa; Kodama, Satoshi

    2000-01-01

    Numerical calculations on heat transfer of a magnetohydrodynamic (MHD) flow with internal heat generation in a rectangular channel have been performed for the cases of very-large Hartmann numbers, finite wall conductivities and small aspect ratio (i.e. small length ratios of the channel side perpendicular to the applied magnetic field and the side parallel to the field), simulating typical conditions for a fusion-reactor blanket. The Nusselt numbers of the MHD flow in rectangular channels with aspect ratios of 1/10 to 1/40 for Hartmann numbers of ∼5 x 10 5 become ∼10 times higher than those for the corresponding flow under no magnetic field. The Nusselt number becomes higher as the internal heat generation rate increases as far as the heat generation rates in a fusion reactor blanket are considered. (author)

  3. Heat shrink formation of a corrugated thin film thermoelectric generator

    International Nuclear Information System (INIS)

    Sun, Tianlei; Peavey, Jennifer L.; David Shelby, M.; Ferguson, Scott; O’Connor, Brendan T.

    2015-01-01

    Highlights: • Demonstrate and characterize a thermoelectric generator with a corrugated geometry. • Employ a novel heat shrink fabrication approach compatible with low-cost processing. • Use thermal impedance modeling to explore design potential. • Corrugated design shown to be advantageous for low heat-flux density applications. - Abstract: A thin film thermoelectric (TE) generator with a corrugated architecture is demonstrated formed using a heat-shrink fabrication approach. Fabrication of the corrugated TE structure consists of depositing thin film thermoelectric elements onto a planar non-shrink polyimide substrate that is then sandwiched between two uniaxial stretch-oriented co-polyester (PET) films. The heat shrink PET films are adhered to the polyimide in select locations, such that when the structure is placed in a high temperature environment, the outer films shrink resulting in a corrugated core film and thermoelectric elements spanning between the outer PET films. The module has a cross-plane heat transfer architecture similar to a conventional bulk TE module, but with heat transfer in the plane of the thin film thermoelectric elements, which assists in maintaining a significant temperature difference across the thermoelectric junctions. In this demonstration, Ag and Ni films are used as the thermoelectric elements and a Seebeck coefficient of 14 μV K −1 is measured with a maximum power output of 0.22 nW per couple at a temperature difference of 7.0 K. We then theoretically consider the performance of this device architecture with high performance thermoelectric materials in the heat sink limited regime. The results show that the heat-shrink approach is a simple fabrication method that may be advantageous in large-area, low power density applications. The fabrication method is also compatible with simple geometric modification to achieve various form factors and power densities to customize the TE generator for a range of applications

  4. Radioactivity

    International Nuclear Information System (INIS)

    Chelet, Y.

    2006-01-01

    The beginning of this book explains the why and how of the radioactivity, with a presentation of the different modes of disintegration. Are tackled the reports between radioactivity and time before explaining how the mass-energy equivalence appears during disintegrations. Two chapters treat natural radioisotopes and artificial ones. This book makes an important part to the use of radioisotopes in medicine (scintigraphy, radiotherapy), in archaeology and earth sciences (dating) before giving an inventory of radioactive products that form in the nuclear power plants. (N.C.)

  5. Radioactivity

    International Nuclear Information System (INIS)

    2002-01-01

    This pedagogical document presents the origin, effects and uses of radioactivity: where does radioactivity comes from, effects on the body, measurement, protection against radiations, uses in the medical field, in the electric power industry, in the food (ionization, radio-mutagenesis, irradiations) and other industries (radiography, gauges, detectors, irradiations, tracers), and in research activities (dating, preservation of cultural objects). The document ends with some examples of irradiation levels (examples of natural radioactivity, distribution of the various sources of exposure in France). (J.S.)

  6. Development of low grade waste heat thermoelectric power generator

    Directory of Open Access Journals (Sweden)

    Suvit Punnachaiya

    2010-07-01

    Full Text Available This research aimed to develop a 50 watt thermoelectric power generator using low grade waste heat as a heat source,in order to recover and utilize the excess heat in cooling systems of industrial processes and high activity radioisotope sources. Electricity generation was based on the reverse operation of a thermoelectric cooling (TEC device. The TEC devices weremodified and assembled into a set of thermal cell modules operating at a temperature less than 100°C. The developed powergenerator consisted of 4 modules, each generating 15 watts. Two cascade modules were connected in parallel. Each modulecomprised of 96 TEC devices, which were connected in series. The hot side of each module was mounted on an aluminumheat transfer pipe with dimensions 12.212.250 cm. Heat sinks were installed on the cold side with cooling fans to provideforced air cooling.To test electricity generation in the experiment, water steam was used as a heat source instead of low grade waste heat.The open-circuit direct current (DC of 250 V and the short-circuit current of 1.2 A was achieved with the following operatingconditions: a hot side temperature of 96°C and a temperature difference between the hot and cold sides of 25°C. The DC poweroutput was inverted to an AC power source of 220 V with 50 Hz frequency, which can continuously supply more than 50 wattsof power to a resistive load as long as the heat source was applied to the system. The system achieved an electrical conversionefficiency of about 0.47 percent with the capital cost of 70 US$/W.

  7. Retrospective dosimetry: dose evaluation using unheated and heated quartz from a radioactive waste storage building

    International Nuclear Information System (INIS)

    Jain, M.; Boetter-Jensen, L.; Murray, A.S.; Jungner, H.

    2002-01-01

    In the assessment of dose received from a nuclear accident, considerable attention has been paid to retrospective dosimetry using heated materials such as household ceramics and bricks. However, unheated materials such as mortar and concrete are more commonly found in industrial sites and particularly in nuclear installations. These materials contain natural dosemeters such as quartz, which usually is less sensitive than its heated counterpart. The potential of quartz extracted from mortar is a wall of a low-level radioactive-waste storage facility containing distributed sources of 60 Co and 13C s has been investigated. Dose-depth profiles based on small aliquots and single grains from the quartz extracted from the mortar samples are reported here. These are compared with results from heated quartz and polymineral fine grains extracted from an adjacent brick, and the integrated dose recorded by environmental TLDs. (author)

  8. Retrospective dosimetry: Dose evaluation using unheated and heated quartz from a radioactive waste storage building

    DEFF Research Database (Denmark)

    Jain, M.; Bøtter-Jensen, L.; Murray, A.S.

    2002-01-01

    In the assessment of dose received from a nuclear accident, considerable attention has been paid to retrospective dosimetry using heated materials such as household ceramics and bricks. However, unheated materials such as mortar and concrete are more commonly found in industrial sites......-137 has been investigated. Dose-depth profiles based on small aliquots and single grains from the quartz extracted from the mortar samples are reported here. These are compared with results from heated quartz and polymineral fine grains extracted from an adjacent brick, and the integrated dose...... and particularly in nuclear installations. These materials contain natural dosemeters Such as quartz. which usually is less sensitive than its heated counterpart. The potential of quartz extracted from mortar in a wall of a low-level radioactive-waste storage facility containing distributed sources of Co-60 and Cs...

  9. Public comments on the draft generic environmental impact statement for management of commercially generated radioactive waste

    International Nuclear Information System (INIS)

    Kreiter, M.R.; Unruh, C.M.; McCallum, R.F.

    1980-01-01

    The US Department of Energy has the responsibility for developing the technology required for managing commercial radioactive wastes in an environmentally acceptable manner. As part of this responsibility, DOE has prepared a draft environmental impact statement on the management of commercially generated radioactive waste. The draft was issued for public comment in April of 1979; five public hearings were held. The draft GEIS is intended to provide environmental input for the selection of an appropriate program strategy for the permanent isolation of commercially generated high-level and transuranic wastes. The scope of such a strategy includes research and development into alternative treatment processes and emplacement media, site investigations into candidate media, and the examination of advanced waste management technologies. The draft statement describes the commercial radioactive wastes that would have to be managed for very long periods of time from an assumed nuclear generation scenario of 10,000 GWe-yr of power over a 65-year period ending in 2040

  10. User's manual for applicants proposing on-site burial of self-generated radioactive waste

    International Nuclear Information System (INIS)

    Tolbert, M.E.M.; Loretan, P.A.

    1987-01-01

    This document describes, for medical and research institutions as well as industrial generators of low-level radioactive waste, the NRC or state submittal requirements for authorizing the on-site burial of self-generated radioactive waste. An important part of completing the license application for operation justifying this alternative for waste disposal over other alternatives. Reasons that might be considered acceptable might include the need to dispose of large volumes of low activity waste that would otherwise take up valuable space in commercial sites; the ability to demonstrate that this method of disposal will result in reduced exposures to the public; the ability to show that the prohibitive costs of other methods of disposal would be detrimental to the progress of significant research which generates radioactive waste. 19 refs., 3 figs., 4 tabs

  11. Heat savings and heat generation technologies: Modelling of residential investment behaviour with local health costs

    International Nuclear Information System (INIS)

    Zvingilaite, Erika; Klinge Jacobsen, Henrik

    2015-01-01

    The trade-off between investing in energy savings and investing in individual heating technologies with high investment and low variable costs in single family houses is modelled for a number of building and consumer categories in Denmark. For each group the private economic cost of providing heating comfort is minimised. The private solution may deviate from the socio-economical optimal solution and we suggest changes to policy to incentivise the individuals to make choices more in line with the socio-economic optimal mix of energy savings and technologies. The households can combine their primary heating source with secondary heating e.g. a woodstove. This choice results in increased indoor air pollution with fine particles causing health effects. We integrate health cost due to use of woodstoves into household optimisation of heating expenditures. The results show that due to a combination of low costs of primary fuel and low environmental performance of woodstoves today, included health costs lead to decreased use of secondary heating. Overall the interdependence of heat generation technology- and heat saving-choice is significant. The total optimal level of heat savings for private consumers decrease by 66% when all have the option to shift to the technology with lowest variable costs. - Highlights: • Heat saving investment and heat technology choice are interdependent. • Health damage costs should be included in private heating choice optimisation. • Flexibility in heating technology choice reduce the optimal level of saving investments. • Models of private and socioeconomic optimal heating produce different technology mix. • Rebound effects are moderate but varies greatly among consumer categories

  12. Considerations for reduction of gas generation in a low-level radioactive waste repository

    International Nuclear Information System (INIS)

    Cho, Chan Hee; Son, Jung Kwon; Lee, Myung Chan; Song, Myung Jae

    1997-01-01

    In a low-level radioactive waste repository, H 2 , CO 2 , and CH 4 will be generated principally by the coupled processes of metal corrosion and microbial degradation of cellulosic waste. The metal corrosion model incorporates a three-stage process encompassing aerobic and anaerobic corrosion regimes; the microbial degradation model simulates the activities of eight different microbial populations, which are maintained as functions both of pH and of the concentrations of particular chemical species. A prediction is made for gas concentrations and generation rates over an assessment period of ten thousand years in a radioactive waste repository. The results suggest that H 2 is the principal gas generated within the radioactive waste cavern. The generation rates of CO 2 and CH 4 are likely to be insignificant by comparison with H 2 . Therefore, an effective way to decrease gas generation in a radioactive waste repository seems to be to reduce metal content since the generation rate of H 2 is most sensitive to the concentration of steel

  13. Radiation after-effects in daughter generations of barley grown under conditions of enhanced radioactive background

    International Nuclear Information System (INIS)

    Popova, O.N.; Shershunova, V.I.; Taskaev, A.I.

    1978-01-01

    Stimulation of growth and development was observed in the first daughter generation of barley plants grown under conditions simulating an enhanced radioactive background. The stimulatory effect was partially reproduced in the second generation, and signs of depression of initial growth of plants were found in the third generation. A great number of alterations and their regular occurrence allow to refer them to lingering modifications originating under the effect of a radiation factor on vegetating plants

  14. Solar hot-water generation and heating - Kombi-Kompakt+

    International Nuclear Information System (INIS)

    Haller, M.; Vogelsanger, P.

    2005-01-01

    This final report for the Swiss Federal Office of Energy (SFOE) describes new testing facilities at the Institute for Solar Technology in Rapperswil, Switzerland, that allow the testing of solar systems the whole year through. The systems tested feature the combined generation of heat for hot water storage vessels and heat for space heating. The test method used, the Concise Cycle Test (CCT) is described. The results of tests made on a large number of systems demonstrate that it is especially important to have a test system that allows the solar market to be protected from unsatisfactory systems. Good co-operation with manufactures is noted. As the test method includes tests with secondary energy sources such as oil or gas, certain problems in this area were discovered and corrected. Further tests are to be made with systems using biomass as a secondary source of heat

  15. Utilization of Aluminum Waste with Hydrogen and Heat Generation

    Science.gov (United States)

    Buryakovskaya, O. A.; Meshkov, E. A.; Vlaskin, M. S.; Shkolnokov, E. I.; Zhuk, A. Z.

    2017-10-01

    A concept of energy generation via hydrogen and heat production from aluminum containing wastes is proposed. The hydrogen obtained by oxidation reaction between aluminum waste and aqueous solutions can be supplied to fuel cells and/or infrared heaters for electricity or heat generation in the region of waste recycling. The heat released during the reaction also can be effectively used. The proposed method of aluminum waste recycling may represent a promising and cost-effective solution in cases when waste transportation to recycling plants involves significant financial losses (e.g. remote areas). Experiments with mechanically dispersed aluminum cans demonstrated that the reaction rate in alkaline solution is high enough for practical use of the oxidation process. In theexperiments aluminum oxidation proceeds without any additional aluminum activation.

  16. Management of radioactive waste generated in nuclear medicine; Gestion de los residuos radiactivos generados en medicina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz Perez, P.

    2015-07-01

    Nuclear medicine is a clinical specialty in which radioactive material is used in non-encapsulated form, for the diagnosis and treatment of patients. Nuclear medicine involves administering to a patient a radioactive substance, usually liquid, both diagnostic and therapeutic purposes. This process generates solid radioactive waste (syringes, vials, gloves) and liquid (mainly the patient's urine). (Author)

  17. Generation of heat on fuel rod in cosine pattern by using induction heating

    International Nuclear Information System (INIS)

    Keettikkal, Felix; Sajeesh, Divya; Rao, Poornima; Hande, Shashank; Dakave, Ganesh; Kute, Tushar; Mahajan, Akshay; Kulkarni, R.D.

    2017-01-01

    Fuel rods are used in a nuclear reactor for fission process. When these rods are cooled by water during the heat transfer, the temperature stress causes undesirable defects in the fuel rod. Studying these defects occurring in the fuel rod in the nuclear cluster during nuclear reaction is a difficult task because fission reaction makes it difficult to analyse the changes in the rod. Hence there is a need to use a replica of the rod with similar thermal stress to study and analyse the rod for the defects. Normally the heat generated on the fuel rod follows a cosine pattern which is an inherent characteristic inside a nuclear reactor. In view of this, in this paper induction heating method is used on a rod to create an exact replica of the cosine pattern of heat by varying the pitch of the coil. First, a MATLAB simulation is done using simulink. Then a prototype of the model has been developed comprising of carbon steel pipe, with length and outside diameter of 1 meter and 48.2 mm, respectively. Instead of using water as coolant, rod is simulated in air. Therefore, the heat generated is lost by normal convection and radiation. Non-nuclear testing can be a valuable tool in the development or in some kind of experiment using nuclear reactor. Induction heating becomes an alternative to classical heating technologies because of its advantages such as efficiency, quickness, safety, clean heating and accurate power control. (author)

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

    International Nuclear Information System (INIS)

    Hughes, Larry

    2010-01-01

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

  19. Power generation using sugar cane bagasse: A heat recovery analysis

    Science.gov (United States)

    Seguro, Jean Vittorio

    The sugar industry is facing the need to improve its performance by increasing efficiency and developing profitable by-products. An important possibility is the production of electrical power for sale. Co-generation has been practiced in the sugar industry for a long time in a very inefficient way with the main purpose of getting rid of the bagasse. The goal of this research was to develop a software tool that could be used to improve the way that bagasse is used to generate power. Special focus was given to the heat recovery components of the co-generation plant (economizer, air pre-heater and bagasse dryer) to determine if one, or a combination, of them led to a more efficient co-generation cycle. An extensive review of the state of the art of power generation in the sugar industry was conducted and is summarized in this dissertation. Based on this models were developed. After testing the models and comparing the results with the data collected from the literature, a software application that integrated all these models was developed to simulate the complete co-generation plant. Seven different cycles, three different pressures, and sixty-eight distributions of the flue gas through the heat recovery components can be simulated. The software includes an economic analysis tool that can help the designer determine the economic feasibility of different options. Results from running the simulation are presented that demonstrate its effectiveness in evaluating and comparing the different heat recovery components and power generation cycles. These results indicate that the economizer is the most beneficial option for heat recovery and that the use of waste heat in a bagasse dryer is the least desirable option. Quantitative comparisons of several possible cycle options with the widely-used traditional back-pressure turbine cycle are given. These indicate that a double extraction condensing cycle is best for co-generation purposes. Power generation gains between 40 and

  20. Generation, transport and conduct of radioactive wastes of low and intermediate level

    International Nuclear Information System (INIS)

    Lizcano, D.; Jimenez, J.

    2005-01-01

    The technological development of the last decades produced an increment in the application of the radiations in different human activities. The effect of it has been it the production of radioactive wastes of all the levels. In Mexico, some of the stages of the administration of the waste of low and intermediate level have not been completely resolved, as the case of the treatment and the final storage. In this work aspects of the generation, the transport and the administration of radioactive waste of low and intermediate level produced in the non energy applications from the radioactive materials to national level, indicating the generated average quantities, transported and tried annually by the National Institute of Nuclear Research (ININ). The main generators of wastes in Mexico, classified according to the activity in which the radioactive materials are used its are listed. Some of the main processes of treatment of radioactive wastes broadly applied in the world and those that are used at the moment in our country are also presented. (Author)

  1. Radioactive Waste Management Produced from the Generator Tc-99m Products

    International Nuclear Information System (INIS)

    Suhaedi Muhammad; Rimin Sumantri; Affan Ahmad; Tuyono

    2012-01-01

    Generator Tc-99m product is used in hospitals will result in radioactive waste both solid waste in the form of a column compacted Tc-99m Generator, bottles vials and bottles of saline fluid path series: burning of solid waste in the form of paper straw, hand gloves, and cardboard (vial packing boxes and wrapping Generator) and liquid waste form leaching results lead pot and enclosure. So that these wastes pose no radiological consequences for both humans and the environment, it must be properly managed in accordance with the provisions. In order to realize these expectations should be made so that the radioactive waste management system can be handled effectively, optimal, economical, safe and secure and in accordance with applicable regulations. Management system is in it include: procedures for handling radioactive waste, solid waste compacted, burning of solid waste management, liquid waste handling, shipment of radioactive waste and determination of the amount of radiation doses received by workers who handle radioactive waste. (author)

  2. The effect of heat generation in inclined slats on the natural convective heat transfer from an isothermal heated vertical plate

    International Nuclear Information System (INIS)

    Oosthuizen, P.H.; Sun, L.; Naylor, D.

    2003-01-01

    Natural convective heat transfer from a wide heated vertical isothermal plate with adiabatic surfaces above and below the heated surface has been considered. There are a series of equally spaced vertical thin, flat surfaces (termed 'slats') near the heated surface, these surfaces being, in general, inclined to the heated surface. There is, in general, a uniform heat generation in the slats. The slats are pivoted about their centre-point and thus as their angle is changed, the distance of the tip of the slat from the plate changes. The situation considered is an approximate model of a window with a vertical blind, the particular case where the window is hotter than the room air being considered. The heat generation in the slats in this situation is the result of solar radiation passing through the window and falling on and being absorbed by the slats of the blind. The flow has been assumed to be laminar and steady. Fluid properties have been assumed constant except for the density change with temperature that gives rise to the buoyancy forces. The governing equations have been written in dimensionless form and the resulting dimensionless equations have been solved using a commercial finite-element package. The solution has the following parameters: (1) the Rayleigh number (2) the Prandtl number (3) the dimensionless heat generation rate in the slats per unit frontal area (4) the dimensionless distance of the slat center point (the pivot point) from the surface (5) the dimensionless slat size (6) the dimensionless slat spacing (7) the angle of inclination of the slats. Because of the application that motivated the study, results have only been obtained for a Prandtl number of 0.7. The effect of the other dimensionless variables on the mean dimensionless heat transfer rate from the heated vertical surface has been examined. (author)

  3. Next Generation Nuclear Plant Steam Generator and Intermediate Heat Exchanger Materials Research and Development Plan

    Energy Technology Data Exchange (ETDEWEB)

    J. K. Wright

    2010-09-01

    DOE has selected the High Temperature Gas-cooled Reactor (HTGR) design for the Next Generation Nuclear Plant (NGNP) Project. The NGNP will demonstrate the use of nuclear power for electricity and hydrogen production. It will have an outlet gas temperature in the range of 900°C and a plant design service life of 60 years. The reactor design will be a graphite moderated, helium-cooled, prismatic or pebble-bed reactor and use low-enriched uranium, Tri-Isotopic (TRISO)-coated fuel. The plant size, reactor thermal power, and core configuration will ensure passive decay heat removal without fuel damage or radioactive material releases during accidents. The NGNP Materials Research and Development (R&D) Program is responsible for performing R&D on likely NGNP materials in support of the NGNP design, licensing, and construction activities. Today’s high-temperature alloys and associated ASME Codes for reactor applications are approved up to 760°C. However, some primary system components, such as the Intermediate Heat Exchanger (IHX) for the NGNP will require use of materials that can withstand higher temperatures. The thermal, environmental, and service life conditions of the NGNP will make selection and qualification of some high-temperature materials a significant challenge. Examples include materials for the core barrel and core internals, such as the control rod sleeves. The requirements of the materials for the IHX are among the most demanding. Selection of the technology and design configuration for the NGNP must consider both the cost and risk profiles to ensure that the demonstration plant establishes a sound foundation for future commercial deployments. The NGNP challenge is to achieve a significant advancement in nuclear technology while at the same time setting the stage for an economically viable deployment of the new technology in the commercial sector soon after 2020. A number of solid solution strengthened nickel based alloys have been considered for

  4. Entropy Generation of Desalination Powered by Variable Temperature Waste Heat

    Directory of Open Access Journals (Sweden)

    David M. Warsinger

    2015-10-01

    Full Text Available Powering desalination by waste heat is often proposed to mitigate energy consumption and environmental impact; however, thorough technology comparisons are lacking in the literature. This work numerically models the efficiency of six representative desalination technologies powered by waste heat at 50, 70, 90, and 120 °C, where applicable. Entropy generation and Second Law efficiency analysis are applied for the systems and their components. The technologies considered are thermal desalination by multistage flash (MSF, multiple effect distillation (MED, multistage vacuum membrane distillation (MSVMD, humidification-dehumidification (HDH, and organic Rankine cycles (ORCs paired with mechanical technologies of reverse osmosis (RO and mechanical vapor compression (MVC. The most efficient technology was RO, followed by MED. Performances among MSF, MSVMD, and MVC were similar but the relative performance varied with waste heat temperature or system size. Entropy generation in thermal technologies increases at lower waste heat temperatures largely in the feed or brine portions of the various heat exchangers used. This occurs largely because lower temperatures reduce recovery, increasing the relative flow rates of feed and brine. However, HDH (without extractions had the reverse trend, only being competitive at lower temperatures. For the mechanical technologies, the energy efficiency only varies with temperature because of the significant losses from the ORC.

  5. Modeling a Thermoelectric Generator Applied to Diesel Automotive Heat Recovery

    Science.gov (United States)

    Espinosa, N.; Lazard, M.; Aixala, L.; Scherrer, H.

    2010-09-01

    Thermoelectric generators (TEGs) are outstanding devices for automotive waste heat recovery. Their packaging, lack of moving parts, and direct heat to electrical conversion are the main benefits. Usually, TEGs are modeled with a constant hot-source temperature. However, energy in exhaust gases is limited, thus leading to a temperature decrease as heat is recovered. Therefore thermoelectric properties change along the TEG, affecting performance. A thermoelectric generator composed of Mg2Si/Zn4Sb3 for high temperatures followed by Bi2Te3 for low temperatures has been modeled using engineering equation solver (EES) software. The model uses the finite-difference method with a strip-fins convective heat transfer coefficient. It has been validated on a commercial module with well-known properties. The thermoelectric connection and the number of thermoelements have been addressed as well as the optimum proportion of high-temperature material for a given thermoelectric heat exchanger. TEG output power has been estimated for a typical commercial vehicle at 90°C coolant temperature.

  6. Systematic analysis method for radioactive wastes generated from nuclear research facilities

    International Nuclear Information System (INIS)

    Kameo, Yutaka; Ishimori, Ken-ichiro; Haraga, Tomoko; Shimada, Asako; Katayama, Atsushi; Nakashima, Mikio; Takahashi, Kuniaki

    2011-01-01

    Analytical methods have been developed for the simple and rapid determination of radioactive nuclides, which are selected as important nuclides for the safety assessment of the disposal of wastes generated from research facilities. We advanced the development of a high-efficiency nondestructive measurement technique for γ-ray-emitting nuclides, simple and rapid methods for the pretreatment of hard-to-dissolve samples and subsequent radiochemical separation, and rapid determination methods for long-lived nuclides. In order to establish a system to analyze the important nuclides in various kinds of sample, actual radioactive wastes such as concentrated liquid waste, activated concrete, and metal pipes were analyzed by the present method. The results showed that the present method was well suited for a rapid and simple determination of low-level radioactive wastes generated from research facilities. (author)

  7. Radioactive solid waste management study of generated in the source production laboratory for brachytherapy

    International Nuclear Information System (INIS)

    Barbosa, Nayane K.O.; Carvalho, Vitória S.; Marques, José R.O.; Costa, Osvaldo L.; Baptista, Tatyana S.; Vicente, Roberto; Rostelato, M.E.C.M.; Zeituni, Carlos A.; Souza, Daiane C.B.

    2017-01-01

    A management system for radioactive solid wastes generated during seed production in the Laboratório de Produção de Fontes para Radioterapia (LPFRT) was developed. For this, the volume and the mass of each item of solid wastes generated in Glove box were estimated. It is possible to estimate, per week, how much reject will enter the warehouse, what space it will occupy and also its weight. In the final step of the characterization, the decay calculation is applied to define the time the reject will be stored for later disposal in the collection system. After the characterization process, it is noticed that the rate of volume and radioactivity decreases as the retention time of the rejects increases due to the release of the materials, and also, there is the decay of the radioactivity present in the reservoir. It is also observed that the rate of entry and exit of the wastes is proportional

  8. Fuel cell - An alternative for power and heat generating

    International Nuclear Information System (INIS)

    Zubcu, Victor; Ursescu, Gabriel; Zubcu, Dorina Silvia; Miler, Mihai Cristian

    2004-01-01

    One of the most promising energy generating technologies is the fuel cell (FC) because of its high efficiency and low emissions. There are even zero chemical emissions FC and cogeneration plants based on FC generate low heat emissions too. FC was invented 160 years ago but it was usually used only since 1960 in space missions. A FC farm tractor was tested 40 years ago. FC was again taken into account by power engineering since 1990 and it is now considered a credible alternative to power and heat generating. The thermal power engineers (and not only they) have two problems of cardinal importance for mankind to solve: - Energy saving (by increasing of energy generating efficiency) and - Environmental protection (by reducing chemical and heat emissions). The possibilities to use FC to generate power and heat are practically endless: on the earth, in the air and outer space, by and under water, in numberless areas of human activities. FC are now powering buses, cars, trains, boats, plains, scooters, highway road signs etc. There are already miniature FC for portable electronics. Homes, schools, hospitals, institutes, banks, police stations, etc are using FC to generate power and heat for their facilities. The methane gas produced by wastewater treatment plants and landfills is converted into electricity by using FC. Being less expensive than nuclear and solar source of energy, FC is now generally used in the space missions (in addition FC generates water). In this work an analysis of the possibilities to use FC especially for combined power and heat generating is presented. FC is favourite as energy source in space missions because it is less expensive than nuclear or solar sources. All major automobile companies have FC powered automobiles in testing stage. Mini FC for phone, laptop, and electronics are already on market. FC will be use to pagers, video recorders, small portable tools, miniature robots, special devices as hearing aid various devices, smoke detectors

  9. Heat production rate from radioactive elements in igneous and metamorphic rocks in Eastern Desert, Egypt

    International Nuclear Information System (INIS)

    Abbady, Adel G.E.; El-Arabi, A.M.; Abbady, A.

    2006-01-01

    Radioactive heat-production data of Igneous and Metamorphic outcrops in the Eastern Desert are presented. Samples were analysed using a low level gamma-ray spectrometer (HPGe) in the laboratory. A total of 205 rock samples were investigated, covering all major rock types of the area. The heat-production rate of igneous rocks ranges from 0.11 (basalt) to 9.53 μW m -3 (granite). In metamorphic rocks it varies from 0.28 (serpentinite ) to 0.91 μW m -3 (metagabbro). The contribution due to U is about 51%, as that from Th is 31% and 18% from K. The corresponding values in igneous rocks are 76%, 19% and 5%, respectively. The calculated values showed good agreement with global values except in some areas containing granites

  10. Heat production rate from radioactive elements in igneous and metamorphic rocks in eastern desert, Egypt

    International Nuclear Information System (INIS)

    Abbady, A G.E.; Arabi, A.M.; Abbay, A.

    2005-01-01

    Radioactive heat - production data of igneous and metamorphic rocks cropping out from the eastern desert are presented. Samples were analysed using low level gamma-ray spectrometer (HPGe) in the laboratory. A total of 205 rock samples were investigated, covering all major rock types of the area. The heat-production rate of igneous rocks ranges from 0.11 (basalt) to 9.53 Μ Wm-3 (granite). In metamorphic rocks it varies from 0.28 (serpentinite) to 0.91 (metagabroo) Μ W.m-3. The contribution due to U is about (51%), whereas that of Th (31%) and (18%) by K. The corresponding values in igneous rocks are 76%: 19%: 5%, respectively. The calculated values showed good agreement with global values expect in some areas contained granite rocks

  11. Maintenance of shutdown system in the reactor core to minimize the radioactive waste generation

    International Nuclear Information System (INIS)

    Ponzoni Filho, P.; Fernandes, V.B.

    1988-01-01

    This paper recommends a modification on the actual strategy of going from Cold-Shutdown to Critical, that will save about 6000 liter of boric acid and 30,000 liters of demineralized water for each reactor criticalization. This strategy will reduce the radioactive waste disposal volume to only about 5% of what would be generated following the actual strategy. (author) [pt

  12. Inter-generational Decision Making for Radioactive Waste Disposal, Policy and Science: Regulatory Protection Forever?

    International Nuclear Information System (INIS)

    Regnier, E.P.; Wallo, A.

    2006-01-01

    Assumptions about this generation's duty to future generations underlie decisions on regulatory requirements for disposal of radioactive waste. Regulatory provisions related to time of compliance, dose criteria, and institutional controls, for example, continue to be topics of discussion as regulations are revised or compared. Subjective and difficult ethical issues are either explicit or implicit in these discussions. The information and criteria used must be relevant and help make good decisions that, ideally, increase the overall welfare of future generations. To what extent can or should science usefully inform such decision-making? Both the National Academies of Science and the National Academy of Public Administration (NAPA) have reported on this topic, albeit from different viewpoints. This paper explains and expands upon the rationale used for setting compliance time periods such as the Department of Energy's requirement for a 1,000 year time of compliance with dose limits for low-level radioactive waste disposal facilities. It evaluates radioactive waste disposal against principles of equity recommended by NAPA. Radioactive waste disposal standards require evaluation of impacts much farther into the future than has been common for other endeavors with very long term effects. While performance assessment analyses provide much useful information, their inherent uncertainties over long time periods preclude the projection of reality. Thus, the usefulness of extremely long projections in supporting good decisions that promote the welfare of future generations is limited. Such decisions are fundamentally a question of resource allocation, equity, and fairness. (authors)

  13. Development of maintenance procedure for plate type heat exchanger taking into account preventing radioactive contamination

    International Nuclear Information System (INIS)

    Terai, Kensuke; Someki, Hiroyuki; Ueda, Yuya

    2017-01-01

    In Japanese pressurized water reactors (PWR), heat loads of spent fuel pools (SFP) is increasing due to rising spent fuels and use of mixed oxide (MOX) fuels. Therefore, SFP cooling capacities are necessary to be enhanced, and replacement of SFP coolers or installation of additional coolers is needed. On the other hand, installation spaces of SFP coolers are limited in existing buildings. Therefore, plate type heat exchangers which can be designed to be compact because of the high heat efficiency have often been adopted for SFP coolers instead of shell and tube type heat exchangers in general use. Plate type heat exchangers have to be overhauled periodically for inspection and gasket replacement. However, in plate type SFP coolers, radioactive SFP water and non-radioactive component cooling water (CCW) alternately run through between each plate. Thus there is a concern that the CCW system may be contaminated by radioactive materials from the SFP water during overhaul of the SFP cooler. In order to solve this problem, we have developed the maintenance procedure of the plate type SFP coolers to prevent CCW side contamination by coating the contaminated surfaces with strippable paint prior to disassembly. Before applying this developed maintenance procedure to actual equipment, we have performed the following verification tests. (1) Confirmation of fundamental characteristics for strippable paint. Firstly, we selected both water-based and solvent-based strippable paints. Secondly, we tested and confirmed the detachability and the drying time of the selected strippable paints respectively. Moreover we also confirmed that the selected strippable paints are appropriate materials from the viewpoint of chemical composition restriction of consumable materials used in nuclear power plant. (2) Confirmation of workability for paint filling, drying and peeling off. The strippable paints need to be peeled off after filling into plate type heat exchanger and draining

  14. Composite electric generator equipped with steam generator for heating reactor coolant

    International Nuclear Information System (INIS)

    Watabe, Masaharu; Soman, Yoshindo; Kawanishi, Kohei; Ota, Masato.

    1997-01-01

    The present invention concerns a composite electric generator having coolants, as a heating source, of a PWR type reactor or a thermonuclear reactor. An electric generator driving gas turbine is disposed, and a superheater using a high temperature exhaust gas of the gas turbine as a heating source is disposed, and main steams are superheated by the superheater to elevate the temperature at the inlet of the turbine. This can increase the electric generation capacity as well as increase the electric generation efficiency. In addition, since the humidity in the vicinity of the exit of the steam turbine is reduced, occurrence of loss and erosion can be suppressed. When cooling water of the thermonuclear reactor is used, the electric power generated by the electric generator driven by the gas turbine can be used upon start of the thermonuclear reactor, and it is not necessary to dispose a large scaled special power source in the vicinity, which is efficient. (N.H.)

  15. Entropy Generation of Shell and Double Concentric Tubes Heat Exchanger

    Directory of Open Access Journals (Sweden)

    basma abbas abdulmajeed

    2016-06-01

    Full Text Available Entropy generation was studied for new type of heat exchanger (shell and double concentric tubes heat exchanger. Parameters of hot oil flow rate, temperature of inlet hot oil and pressure drop were investigated with the concept of entropy generation. The results showed that the value of entropy generation increased with increasing the flow rate of hot oil and when cold water flow rate was doubled from 20 to 40 l/min, these values were larger. On the other hand, entropy generation increased with increasing the hot oil inlet temperature at a certain flow rate of hot oil. Furthermore, at a certain hot oil inlet temperature, the entropy generation increased with the pressure drop at different hot oil inlet flow rates. Finally, in order to keep up with modern technology, infrared thermography camera was used in order to measure the temperatures. The entropy generation was determined with lower values when infrared thermography camera was used to measure the temperatures, compared with the values obtained by using thermocouples.

  16. An aerosole generator for production of radioactive aerosoles by evaporating uranium dioxide

    International Nuclear Information System (INIS)

    Pusch, W.M.

    1975-01-01

    In the Institut for Biology of the Austrian Research Center at Seibersdorf an experiment is running to study the behaviour of radioactive aerosoles in the organism of miniature swines after inhalation. In the work under discussion the aerosole generator of the equipment used for this inhalation experiments is described by means of which the aerosole-air mixtures are produced. The main part of this generator is a gas burner for evaporating irradiated UO 2 -pellets. (orig.) [de

  17. Economic aspects of electricity and industrial heat generating reactors

    International Nuclear Information System (INIS)

    Gaussens, J.; Moulle, N.; Dutheil, F.

    1964-01-01

    The economic advantage of electricity-generating nuclear stations decreases when their size decreases. However, when a counter-pressure turbine is joined on to a reactor and the residual heat can be properly used, it can be shown that fairly low capacity nuclear equipment may compete with conventional equipment under certain realistic enough conditions. The aim of this paper is to define these special conditions under which nuclear energy can be profitable. They are connected with the location and the general economic environment of the station, the pattern of the electricity and heat demands it must meet, the level of fuel and specific capital costs, nuclear and conventional. These conditions entail certain technical and economic specifications for the reactors used in this way otherwise they are unlikely to be competitive. In addition, these results are referred to the potential steam and electricity market, which leads us to examine certain uses for the heat generated by double purpose power stations; for example, to supply combined industrial plants, various types of town heating and for removal of salt from sea water. (authors) [fr

  18. Development of disposal technologies for radioactive waste generated from radioisotope users and research institutes

    International Nuclear Information System (INIS)

    Sakai, Akihiro; Yoshimori, Michiro

    2001-01-01

    In order to safely dispose of a radioactive waste, which is generated from radioisotope users and research institutes, investigation of characteristics of the waste and conceptual design of disposal facility were carried out. As a result of investigating JAERI that the waste has mainly been stored, it became clear that radioactivities of 19 nuclides are important from the viewpoint of the safety of the disposal. And the result of the conceptual design of disposal facilities on the assumption of 3 kinds of sites, the differences on the safety could not be recognized in either case, though the installation depth to construct the facilities influenced the economical efficiency. (author)

  19. Heat savings in energy systems with substantial distributed generation

    DEFF Research Database (Denmark)

    Østergaard, Poul Alberg

    2004-01-01

    The integration of flutuating wind power is an important issue for the future development of sustainable energy systems. In Denmark, the integration is affected by a large amount of cogeneration of heat and power. This gives possibilities as well as sets restraints. The paper shows that with anci...... that with ancillary services supplied by large-scale condensation and CHP-plants, a certain degree of large-scale generation is required regardless of momentary wind input....

  20. Heat-pipe assisted thermoelectric generators for exhaust gas applications

    OpenAIRE

    Gonçalves, L. M.; Martins, Jorge; Antunes, Joaquim; Rocha, Romeu; Brito, F. P.

    2012-01-01

    Millions of hybrid cars are already running on our roads with the purpose of reducing fossil fuel dependence. One of their main advantages is the recovery of wasted energy, namely by brake recovery. However, there are other sources of wasted energy in a car powered by an internal combustion engine, such as the heat lost through the cooling system, lubrication system (oil coolers) and in the exhaust system. These energies can be recuperated by the use of thermoelectric generators (TEG) based o...

  1. Mechanical design of a sodium heated steam generator

    International Nuclear Information System (INIS)

    Chetal, S.C.

    1975-01-01

    FBTR steam generator is a once through type unit consisting of four 12.5 MW thermal modules generating a total of 74 tons per hour of steam at 125 bar and 480 0 C. This paper outlines the mechanical design of such type of steam generator with emphasis on special design problems associated with this type of sodium to water steam heat exchanger, namely, thermal cycling of transition zone where nucleate boiling changes over to film boiling, application of pressure vessel design criteria for transient pressures, thermal stress evaluation resulting from differential expansion between shell and tube in this typical configuration, sodium headers support design, thermal sleeve, design, thermal shock analysis in thick tubes, thermal stress resulting from stratification and stability of expansion bends against vibration. Some of the possible design changes for the future large size steam generator are outlined. (author)

  2. Modeling of heat transfer in a horizontal heat-generating layer by an effective diffusivity approach

    International Nuclear Information System (INIS)

    Cheung, F.B.; Shiah, S.W.

    1994-01-01

    The concept of effective diffusivity is employed to model various processes of heat transfer in a volumetrically heated fluid layer subjected to different initial and boundary conditions. The approach, which involves the solution of only heat diffusion equations, is found to give rather accurate predictions of the transient response of an initially stagnant fluid layer to a step input of power as well as the developing and decaying nature of the flow following a step change in the internal Rayleigh number from one state of steady convection to another. The approach is also found to be applicable to various flow regions of a heat-generating fluid layer, and is not limited to the case in which the entire layer is in turbulent motion. The simplicity and accuracy of the method are clearly illustrated in the analysis. Validity of the effective diffusivity approach is demonstrated by comparing the predicted results with corresponding experimental data

  3. Power generation from low-temperature heat source

    Energy Technology Data Exchange (ETDEWEB)

    Lakew, Amlaku Abie

    2012-07-01

    transcritical power cycle is operating at lower pump efficiency, the effect of a decrease in pump efficiency is equivalent to a decrease in turbine efficiency. The thermodynamic analysis is coupled with a 1D mean line turbine design. Both axial and radial turbines are considered. The Ainely and Mathieson loss model is used in the 1D axial turbine designs. It is observed that the blade height is generally small; the reason being high operating pressure and low flow rate. A novel approach to enhance the performance of low-temperature CO{sub 2} transcritical power cycles is investigated. From the thermodynamic analysis, it is observed that the pump work is significant and reduction of pump work will be translated to a gain in net power output. The mechanical driven pump is suggested to be replaced by a thermally driven pump. The working principle of thermally driven pump is by exploiting the phenomena in which the pressure of a closed vessel filled full with saturated liquid will rise when heated. A cascade of vessels is used to make the pressurizing process continuous. The time taken to pressurize is an important parameter for the performance of thermally driven pump. Pressurizing time depends on isochoric specific heat capacity of the working fluid, heat transfer coefficient, inlet conditions of heat source, tube diameter, and initial mass of the working fluid. When the pressurizing time is longer, more vessels are required to make the process continuous. It is shown that it possible to increase power output using a thermal driven pump, but additional equipments are required. An example of a possible application is a low-temperature CO{sub 2} power cycle integrated with a post-combustion carbon dioxide capture plant. The heat rejected by low temperature streams in the capture plant is used as a heat sources for power generation. It is found that utilization of heat of the capture plant improves the performance of the overall process. It shows that low-temperature transcritical

  4. Physics and Technology for the Next Generation of Radioactive Ion Beam Facilities: EURISOL

    CERN Document Server

    Kadi, Y; Catherall, R; Giles, T; Stora, T; Wenander, F K

    2012-01-01

    Since the discovery of artificial radioactivity in 1935, nuclear scientists have developed tools to study nuclei far from stability. A major breakthrough came in the eighties when the first high energy radioactive beams were produced at Berkeley, leading to the discovery of neutron halos. The field of nuclear structure received a new impetus, and the major accelerator facilities worldwide rivalled in ingenuity to produce more intense, purer and higher resolution rare isotope beams, leading to our much improved knowledge and understanding of the general evolution of nuclear properties throughout the nuclear chart. However, today, further progress is hampered by the weak beam intensities of current installations which correlate with the difficulty to reach the confines of nuclear binding where new phenomena are predicted, and where the r-process path for nuclear synthesis is expected to be located. The advancement of Radioactive Ion Beam (RIB) science calls for the development of so-called next-generation facil...

  5. Evaluation of site-generated radioactive waste treatment and disposal methods for the Yucca Mountain repository

    International Nuclear Information System (INIS)

    Subramanian, C.V.; Jardine, L.J.

    1989-01-01

    This study identifies the sources of radioactive wastes that may be generated at the proposed high-level waste (HLW) repository at Yucca Mountain, NV, estimates the waste quantities and characteristics, compares technologies available for waste treatment and disposal, and develops recommended concepts for site-generated waste treatment and disposal. The scope of this study is limited to operations during the emplacement phase, in which 70,000 MTU of high-level waste will be received and emplaced at the proposed repository. The evaluations consider all radioactive wastes generated during normal operations in surface and underground facilities. Wastes generated as a result of accidents are not addressed; accidents that could result in large quantities of radioactive waste are expected to occur very infrequently and temporary, portable systems could be used for any necessary cleanup. The results of this study can be used to develop more definitive plans for managing the site-generated wastes and as a basis for the design of associated facilities at the proposed repository

  6. 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.

  7. Heat of hydration measurements on cemented radioactive wastes. Part 1: cement-water pastes

    International Nuclear Information System (INIS)

    Lee, D.J.

    1983-12-01

    This report describes the hydration of cement pastes in terms of chemical and kinetic models. A calorimetric technique was used to measure the heat of hydration to develop these models. The effects of temperature, water/cement ratio and cement replacements, ground granulated blast furnace slag (BFS) and pulverised fuel ash (PFA) on the hydration of ordinary Portland cement (OPC) is reported. The incorporation of BFS or PFA has a marked effect on the hydration reaction. The effect of temperature is also important but changing the water/cement ratio has little effect. Results from cement pastes containing only water and cement yield total heats of reaction of 400, 200 and 100 kJ/kg for OPC, BFS and PFA respectively. Using the results from the models which have been developed, the effect of major salts present in radioactive waste streams can be assessed. Values of the total heat of reaction, the time to complete 50 percent reaction, and the energy of activation, can be compared for different waste systems. (U.K.)

  8. An experimental study of the enhanced heating capacity of an electric heat pump (EHP) using the heat recovered from a gas engine generator

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Cheol Min; Chang, Se Dong [HAC R and D Laboratory, LG Electronics, 327-23 Gasan-Dong, Geumcheon-gu, Seoul 153-802 (Korea); Lee, Jaekeun; Hwang, Yujin [School of Mechanical Engineering, Pusan National University, San 30, Changjeon-Dong, Keumjeong-Ku, Busan 609-735 (Korea)

    2009-11-15

    This paper is concerned with the effect of recovered heat on the heating capacity of an Electric Heat Pump (EHP), which is supplied with electric power and recovered heat from a gas engine generator system. Two methods of supplying recovery heat are examined: (i) to the refrigerant with the discharge line heat exchanger (HEX), and (ii) to the refrigerant of the evaporator with the sub-evaporator. Heating capacity, input power and coefficient of performance (COP) were investigated and compared for each heat recovery method. Conclusively, we found that the second method was most reasonable to recover wasted heat and increased system COP by 215%. (author)

  9. Design and optimization of geothermal power generation, heating, and cooling

    Science.gov (United States)

    Kanoglu, Mehmet

    Most of the world's geothermal power plants have been built in 1970s and 1980s following 1973 oil crisis. Urgency to generate electricity from alternative energy sources and the fact that geothermal energy was essentially free adversely affected careful designs of plants which would maximize their performance for a given geothermal resource. There are, however, tremendous potentials to improve performance of many existing geothermal power plants by retrofitting, optimizing the operating conditions, re-selecting the most appropriate binary fluid in binary plants, and considering cogeneration such as a district heating and/or cooling system or a system to preheat water entering boilers in industrial facilities. In this dissertation, some representative geothermal resources and existing geothermal power plants in Nevada are investigated to show these potentials. Economic analysis of a typical geothermal resource shows that geothermal heating and cooling may generate up to 3 times as much revenue as power generation alone. A district heating/cooling system is designed for its incorporation into an existing 27 MW air-cooled binary geothermal power plant. The system as designed has the capability to meet the entire heating needs of an industrial park as well as 40% of its cooling needs, generating potential revenues of $14,040,000 per year. A study of the power plant shows that evaporative cooling can increase the power output by up to 29% in summer by decreasing the condenser temperature. The power output of the plant can be increased by 2.8 percent by optimizing the maximum pressure in the cycle. Also, replacing the existing working fluid isobutane by butane, R-114, isopentane, and pentane can increase the power output by up to 2.5 percent. Investigation of some well-known geothermal power generation technologies as alternatives to an existing 12.8 MW single-flash geothermal power plant shows that double-flash, binary, and combined flash/binary designs can increase the

  10. Modelling hot electron generation in short pulse target heating experiments

    Directory of Open Access Journals (Sweden)

    Sircombe N.J.

    2013-11-01

    Full Text Available Target heating experiments planned for the Orion laser facility, and electron beam driven fast ignition schemes, rely on the interaction of a short pulse high intensity laser with dense material to generate a flux of energetic electrons. It is essential that the characteristics of this electron source are well known in order to inform transport models in radiation hydrodynamics codes and allow effective evaluation of experimental results and forward modelling of future campaigns. We present results obtained with the particle in cell (PIC code EPOCH for realistic target and laser parameters, including first and second harmonic light. The hot electron distributions are characterised and their implications for onward transport and target heating are considered with the aid of the Monte-Carlo transport code THOR.

  11. Thermal Behavior and Heat Generation Modeling of Lithium Sulfur Batteries

    DEFF Research Database (Denmark)

    Stroe, Daniel-Ioan; Knap, Vaclav; Swierczynski, Maciej Jozef

    2017-01-01

    Lithium Sulfur batteries are receiving a lot of research interest because of their intrinsic characteristics, such as very high energy density and increased safety, which make them a suitable solution for zero-emission vehicles and space application. This paper analyses the influence of the tempe......Lithium Sulfur batteries are receiving a lot of research interest because of their intrinsic characteristics, such as very high energy density and increased safety, which make them a suitable solution for zero-emission vehicles and space application. This paper analyses the influence...... of the temperature on the performance parameters of a 3.4 Ah Lithium-Sulfur battery cell. Furthermore, the values of the internal resistance and entropic heat coefficient, which are necessary for the parametrization of a heat generation model, are determined experimentally....

  12. Heating and generation of suprathermal particles at collisionless shocks

    International Nuclear Information System (INIS)

    Thomsen, M.F.

    1985-01-01

    Collisionless plasma shocks are different from ordinary collisional fluid shocks in several important respects. They do not in general heat the electrons and ions equally, nor do they produce Maxwellian velocity distributions downstream. Furthermore, they commonly generate suprathermal particles which propagate into the upstream region, giving advance warning of the presence of the shock and providing a ''seed'' population for further acceleration to high energies. Recent space observations and theory have revealed a great deal about the heating mechanisms which occur in collisionless shocks and about the origin of the various suprathermal particle populations which are found in association with them. An overview of the present understanding of these subjects is presented herein. 83 refs., 8 figs

  13. Report on the disposal of radioactive wastes and spent fuel elements from Baden-Wuerttemberg; Bericht ueber die Entsorgung von radioaktiven Abfaellen und abgebrannten Brennelementen aus Baden-Wuerttemberg

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2017-04-15

    The report on the disposal of radioactive wastes and spent fuel elements from Baden- Wuerttemberg covers the following issues: legal framework for the nuclear disposal; producer of spent fuels and radioactive wastes in Baden- Report on the disposal of radioactive wastes and spent fuel elements from Baden- Wuerttemberg; low- and medium-level radioactive wastes (non heat generating radioactive wastes); spent fuels and radioactive wastes from waste processing (heat generating radioactive wastes); final disposal.

  14. A thermoelectric generator using loop heat pipe and design match for maximum-power generation

    KAUST Repository

    Huang, Bin-Juine

    2015-09-05

    The present study focuses on the thermoelectric generator (TEG) using loop heat pipe (LHP) and design match for maximum-power generation. The TEG uses loop heat pipe, a passive cooling device, to dissipate heat without consuming power and free of noise. The experiments for a TEG with 4W rated power show that the LHP performs very well with overall thermal resistance 0.35 K W-1, from the cold side of TEG module to the ambient. The LHP is able to dissipate heat up to 110W and is maintenance free. The TEG design match for maximum-power generation, called “near maximum-power point operation (nMPPO)”, is studied to eliminate the MPPT (maximum-power point tracking controller). nMPPO is simply a system design which properly matches the output voltage of TEG with the battery. It is experimentally shown that TEG using design match for maximum-power generation (nMPPO) performs better than TEG with MPPT.

  15. Numerical investigation of conjugate heat transfer and flow performance of a fin and tube heat exchanger with vortex generators

    DEFF Research Database (Denmark)

    Singh, Shobhana; Sørensen, Kim

    2017-01-01

    Vortex generator is considered as an effective device for augmentation of the thermal-hydraulic performance of a heat exchanger. The aim of present study is to examine the influence of vortex generators on a double fin and tube heat exchanger performance. Vortex generator of rectangular winglet...

  16. Measurement of residual radioactive surface contamination by 2-D laser heated TLD

    International Nuclear Information System (INIS)

    Jones, S.C.

    1997-06-01

    The feasibility of applying and adapting a two-dimensional laser heated thermoluminescence dosimetry system to the problem of surveying for radioactive surface contamination was studied. The system consists of a CO 2 laser-based reader and monolithic arrays of thin dosimeter elements. The arrays consist of 10,201 thermoluminescent phosphor elements of 40 micron thickness, covering a 900 cm 2 area. Array substrates are 125 micron thick polyimide sheets, enabling them to easily conform to regular surface shapes, especially for survey of surfaces that are inaccessible for standard survey instruments. The passive, integrating radiation detectors are sensitive to alpha and beta radiation at contamination levels below release guideline limits. Required contact times with potentially contaminated surfaces are under one hour to achieve detection of transuranic alpha emission at 100 dpm/100 cm 2 . Positional information obtained from array evaluation is useful for locating contamination zones. Unique capabilities of this system for survey of sites, facilities and material include measurement inside pipes and other geometrical configurations that prevent standard surveys, and below-surface measurement of alpha and beta emitters in contaminated soils. These applications imply a reduction of material that must be classified as radioactive waste by virtue of its possibility of contamination, and cost savings in soil sampling at contaminated sites

  17. Salt disposal of heat-generating nuclear waste

    International Nuclear Information System (INIS)

    Leigh, Christi D.; Hansen, Francis D.

    2011-01-01

    This report summarizes the state of salt repository science, reviews many of the technical issues pertaining to disposal of heat-generating nuclear waste in salt, and proposes several avenues for future science-based activities to further the technical basis for disposal in salt. There are extensive salt formations in the forty-eight contiguous states, and many of them may be worthy of consideration for nuclear waste disposal. The United States has extensive experience in salt repository sciences, including an operating facility for disposal of transuranic wastes. The scientific background for salt disposal including laboratory and field tests at ambient and elevated temperature, principles of salt behavior, potential for fracture damage and its mitigation, seal systems, chemical conditions, advanced modeling capabilities and near-future developments, performance assessment processes, and international collaboration are all discussed. The discussion of salt disposal issues is brought current, including a summary of recent international workshops dedicated to high-level waste disposal in salt. Lessons learned from Sandia National Laboratories' experience on the Waste Isolation Pilot Plant and the Yucca Mountain Project as well as related salt experience with the Strategic Petroleum Reserve are applied in this assessment. Disposal of heat-generating nuclear waste in a suitable salt formation is attractive because the material is essentially impermeable, self-sealing, and thermally conductive. Conditions are chemically beneficial, and a significant experience base exists in understanding this environment. Within the period of institutional control, overburden pressure will seal fractures and provide a repository setting that limits radionuclide movement. A salt repository could potentially achieve total containment, with no releases to the environment in undisturbed scenarios for as long as the region is geologically stable. Much of the experience gained from United

  18. Salt disposal of heat-generating nuclear waste.

    Energy Technology Data Exchange (ETDEWEB)

    Leigh, Christi D. (Sandia National Laboratories, Carlsbad, NM); Hansen, Francis D.

    2011-01-01

    This report summarizes the state of salt repository science, reviews many of the technical issues pertaining to disposal of heat-generating nuclear waste in salt, and proposes several avenues for future science-based activities to further the technical basis for disposal in salt. There are extensive salt formations in the forty-eight contiguous states, and many of them may be worthy of consideration for nuclear waste disposal. The United States has extensive experience in salt repository sciences, including an operating facility for disposal of transuranic wastes. The scientific background for salt disposal including laboratory and field tests at ambient and elevated temperature, principles of salt behavior, potential for fracture damage and its mitigation, seal systems, chemical conditions, advanced modeling capabilities and near-future developments, performance assessment processes, and international collaboration are all discussed. The discussion of salt disposal issues is brought current, including a summary of recent international workshops dedicated to high-level waste disposal in salt. Lessons learned from Sandia National Laboratories' experience on the Waste Isolation Pilot Plant and the Yucca Mountain Project as well as related salt experience with the Strategic Petroleum Reserve are applied in this assessment. Disposal of heat-generating nuclear waste in a suitable salt formation is attractive because the material is essentially impermeable, self-sealing, and thermally conductive. Conditions are chemically beneficial, and a significant experience base exists in understanding this environment. Within the period of institutional control, overburden pressure will seal fractures and provide a repository setting that limits radionuclide movement. A salt repository could potentially achieve total containment, with no releases to the environment in undisturbed scenarios for as long as the region is geologically stable. Much of the experience gained from

  19. Selection of targets and ion sources for RIB generation at the Holifield Radioactive Ion Beam Facility

    International Nuclear Information System (INIS)

    Alton, G.D.

    1995-01-01

    In this report, the authors describe the performance characteristics for a selected number of target ion sources that will be employed for initial use at the Holifield Radioactive Ion Beam Facility (HRIBF) as well as prototype ion sources that show promise for future use for RIB applications. A brief review of present efforts to select target materials and to design composite target matrix/heat-sink systems that simultaneously incorporate the short diffusion lengths, high permeabilities, and controllable temperatures required to effect fast and efficient diffusion release of the short-lived species is also given

  20. A heat transfer study for vertical straight-tube steam generators heated by liquid metal

    International Nuclear Information System (INIS)

    Valette, M.

    1984-04-01

    A single-tube mockup of a vertical straight-tube steam generator heated by sodium-potassium alloy NaK was submitted to thermal and hydraulic testing in conditions representative of fast breeder reactor operation. The mockup consisted of a 10mm I.D. ferritic steel heat exchange tube centered inside a cylindrical stainless steel shell. The complete assembly was 20.9 meters long. Water flowed upward inside the exchange tube, and NaK flowed downward in the annular gap between the tube and the shell. The steam outlet pressure ranged from 90 to 195 bars, while the liquid metal temperature at the mockup inlet was between 480 and 580 0 C. The water flowrate in the tube ranged from 153 to 2460 kg.m -2 .s -1 . During the tests the fluid inlet and outlet temperatures, flowrate and pressures were measured, as was the NaK temperature profile over the full length of the device. The test results were subsequently compared with heat exchange and pressure drop values calculated using the standard formulas for straight-tube heat exchangers. The heat exchange coefficients predicted by these correlations in the boiling zone were found to be largely overestimated, while the calculated pressure drop values proved satisfactory. A set of modified correlations is proposed to account for the observed phenomena, and for use in designing commercial units, provided the sodium flow in the tube bundle is adequately distributed

  1. Gas generation in deep radioactive waste repositories: a review of processes, controls and models

    International Nuclear Information System (INIS)

    Jones, M.A.

    1990-10-01

    Gas generation within radioactive waste repositories may produce two general problems: 1) breaching of engineered and natural barriers due to high gas pressures; 2) enhanced radiological risk due to reduced groundwater travel times and/or greater aqueous or gaseous activities reaching the biosphere. As a result of these concerns, HMIP must be aware of the current status of relevant research, together with any associated deficiencies. This report addresses the current status of published research on near-field gas generation from worldwide sources and documents the important gas generating processes, the factors controlling them and models available to simulate them. In the absence of suitable models, outline technical specifications for corrosion and microbial degradation gas generation models are defined and the deficiencies in the current understanding of gas generation are highlighted; a conceptual research programme to correct these deficiencies is presented. (author)

  2. High-Temperature Reactor For Power Generation and District Heating

    International Nuclear Information System (INIS)

    Herzberger, Karlheinz

    1987-01-01

    The multinational BBC Brown Brave Group, which has its head-quarters in Baden/Switzerland, was founded in 1891. Its German company is Brown, Brave and CIEs AGM, Mannheim. The field of operation covers wide areas of electrical engineering: These includes mainly the manufacture of installations and equipment for the generation, conversion, distribution and utilization of electric power, with special emphasis on the capital goods sector. BBC erects turnkey power plants and manufactures electrical equipment for industrial plants and urban transport and main line trains. Also of major importance are standard electrical products such as motors, switches, cables, semiconductor devices as well as measuring and control equipment. In the field of nuclear power BBC is engaged in particular in the development and construction of high-temperature reactors for the generation of electric power and process heat. The following presentation gives a short view on the milestones of the HTR development achieved in 1987

  3. Radioactivity in coal, ashes and selected wastewaters from Canadian coal-fired steam electric generating stations

    International Nuclear Information System (INIS)

    1985-09-01

    Coal is known to contain naturally occurring radioactive elements and there has been speculation that as a results, coal-fuelled power generation stations may be significant emitters of these substances. In this report, the subject of radioactivity is introduced. The kinds of radioactive substances which occur naturally in coal formations, the nature of their emissions and the existing information on their behaviour and their effects on environmental organisms are also reviewed. The results of an examination of levels of alpha, beta and gamma radiaton levels, and the substances which produce them in coals, fly ashes, bottom ashes and related wastewaters at six Canadian coal-fuelled power stations are presented. Difficulties in studies of this nature and the potential effects of these releases on organisms in the adjacent aquatic environment are discussed. Existing and potential technologies for the removal of these substances from wastewaters are examined. In general the releases in wastewaters from the six stations were found to be lower than those known to cause short-term or acute biological effects. The potential for long-term effects from such low-level releases could not be accurately assessed because of the paucity of information. A number of recommendations for: improvements in further studies of this nature; the further examination of the fate of naturally occurring radionuclides in the environment; and the determination of the long-term effects of low levels of naturally occurring radioactive substances on aquatic organisms, are made

  4. A Critical Heat Generation for Safe Nuclear Fuels after a LOCA

    Directory of Open Access Journals (Sweden)

    Jae-Yong Kim

    2014-01-01

    Full Text Available This study applies a thermo-elasto-plastic-creep finite element procedure to the analysis of an accidental behavior of nuclear fuel as well as normal behavior. The result will be used as basic data for the robust design of nuclear power plant and fuels. We extended the range of mechanical strain from small or medium to large adopting the Hencky logarithmic strain measure in addition to the Green-Lagrange strain and Almansi strain measures, for the possible large strain situation in accidental environments. We found that there is a critical heat generation after LOCA without ECCS (event category 5, under which the cladding of fuel sustains the internal pressure and temperature for the time being for the rescue of the power plant. With the heat generation above the critical value caused by malfunctioning of the control rods, the stiffness of cladding becomes zero due to the softening by high temperature. The weak position of cladding along the length continuously bulges radially to burst and to discharge radioactive substances. This kind of cases should be avoid by any means.

  5. Nuclear heat generating plants - technical concepts and market potentials. Chapter 8

    International Nuclear Information System (INIS)

    Thoene, E.

    1988-01-01

    To determine the advantages and disadvantages of different heat generating systems, a comparison is made between nuclear heat generating plants and competing heat generating systems. Nuclear heat generating plant concepts in practice have to compete with a wide range of existing and new fossil heat generating technologies of the most different capacities, ranging from combined heat and power generation to individual heating in one-family houses. Heat generation costs are calculated by means of a dynamic annuity method from an economic point of view. The development of real prices of fossil energy sources is based on two scenarios characterized as follows: scenario I - insignificant price increase by the year 2000, then stagnant; scenario II - moderate price increase by the year 2010, then stagnant. As a result of that systems comparison it can be stated that the considered nuclear heat generating plants may be an interesting competitive heat generation option, provided the assumptions on which the study is based can be implemented. This applies especially to investment costs. At the same time those plants contribute to a diversification of energy source options on the heat market. Their use leads to a reduction of fossil fuel imports, increasing at the same time short- and long-term supply guarantees. If nuclear heat generating plants substitute fossil heat generating plants, or render the construction of new ones superfluous, they contribute to avoiding chemical air pollutants. (orig./UA) [de

  6. Analysis of a furnace for heat generation using polydisperse biomass

    Energy Technology Data Exchange (ETDEWEB)

    Magalhaes, Edney Alves; Silva, Juarez de Sousa e; Silva, Jadir Nogueira da; Oliveira Filho, Delly [Universidade Federal de Vicosa (DEA/UFV), MG (Brazil). Dept. de Engenharia Agricola; Donzeles, Sergio Mauricio Lopes [Empresa de Pesquisa Agropecuaria de Minas Gerais (EPAMIG), Vicosa, MG (Brazil)

    2008-07-01

    In many agro-industrial activities, the processing of raw material generates a substantial amount of fine materials. Examples include the production of soluble coffee, processing of rice, and wood processing, among others. In many regions, these by-products keep piling up on the courtyard of companies or become an environmental problem for land dumps. However, detailed tests of these byproducts indicate that they are excellent sources of energy. With this in mind, a furnace was developed to generate clean and hot air, using the alimentation system for pneumatic transport. Wood sawdust was used as fuel for analysis. The obtained results were considered satisfactory, proven by the small heat losses, primarily by the non-burned carbon monoxide (less than 0.2%) and the cooling of the furnace (less than 2.5%) whereas the losses by the exhaust gases were a little more than 23%. The thermal efficiency of the furnace was considered high when compared to others with an indirect heating system, obtaining an average value of 73%. The developed furnace, beyond being efficient, allows the use of the waste from the wood industry, which is important in the reduction of environmental impacts and minimizing production costs associated with the acquisition of conventional energy. (author)

  7. Generation and Sustainment of Plasma Rotation by ICRF Heating

    Science.gov (United States)

    Perkins, F. W.

    2000-10-01

    When tokamak plasmas are heated by the fundamental minority ion-cyclotron process, they are observed to rotate toroidally, even though this heating process introduces negligable angular momentum. This work proposes and evaluates a physics mechanism which resolves this apparent conflict. The argument has two elements. First, it is assumed that angular momentum transport is governed by a diffusion equation with a v_tor = 0 boundary condition at the plasma surface and a torque-density source. When the source consists of separated regions of positive and negative torque density, a finite central rotation velocity results, even though the volume integrated torque density - the angular momentum input - vanishes. Secondly, ions energized by the ICRF process can generate separated regions of positive and negative torque density. Heating increases their banana widths which leads to radial energetic-particle transport that must be balanced by neutralizing radial currents and a j_rB_pR torque density in the bulk plasma. Additional, comparable torque density results from collisional transfer of mechanical angular momentum from energetic particles to the bulk plasma and particle loss through banana particles impacting the wall. Monte-Carlo calculations utilizing the ORBIT code evaluate all sources of torque density and rigorously assure that no net angular momentum is introduced. Two models of ICRF heating, diffusive and instantaneous, give similar results. When the resonance location is on the LFS, the calculated rotation has the magnitude, profile, and co-current sense of Alcator C-Mod observations. For HFS resonance locations, the model predicts counter-current rotation. Scans of rotational profiles vs. resonance location, initial energy, particle loss, pitch, and qm will be presented as will the location of the velocity shear layer its scaling to a reactor.

  8. The far field heating effects of a radioactive waste depository in hard rock

    International Nuclear Information System (INIS)

    Hodgkinson, D.P.; Bourke, P.J.

    1978-01-01

    Fission product heating of the rock surrounding a depository for high level radioactive waste, will result in high temperatures and high thermal gradients over distances of several hundred metres for many centuries. The consequent thermal expansion of the rock leads to stresses which could alter the fracture pattern and therefore the permeability of the rock. These problems are assessed by considering an idealised model of a depository for which analytic solutions to the temperature and stress fields are derived. A related problem is that any water present in the fissures will tend to rise because of its decrease in density on heating. If the water had previously leached away some of the radionuclides in the waste, then this convective transport constitutes a possible leakage path back to the biosphere. For the low permeabilities expected at a depository site, it is possible to linearise the resulting equations and derive analytic solutions for the flow velocities. This procedure has been carried out for the idealised depository model, in order to estimate the magnitude of these effects

  9. Generation projection of solid and liquid radioactive wastes and spent radioactive sources in Mexico; Proyeccion de generacion de desechos radiactivos solidos, liquidos y fuentes radiactivas gastadas en Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Garcia A, E.; Hernandez F, I. Y.; Fernandez R, E. [Universidad Politecnica del Valle de Toluca, Km 5.7 Carretera Almoloya de Juarez, Estado de Mexico (Mexico); Monroy G, F.; Lizcano C, D., E-mail: fabiola.monroy@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2014-10-15

    This work is focused to project the volumes of radioactive aqueous liquid wastes and spent radioactive sources that will be generated in our country in next 15 years, solids compaction and radioactive organic liquids in 10 years starting from the 2014; with the purpose of knowing the technological needs that will be required for their administration. The methodology involves six aspects to develop: the definition of general objectives, to specify the temporary horizon of projection, data collection, selection of the prospecting model and the model application. This approach was applied to the inventory of aqueous liquid wastes, as well as radioactive compaction organic and solids generated in Mexico by non energy applications from the 2001 to 2014, and of the year 1997 at 2014 for spent sources. The applied projection models were: Double exponential smoothing associating the tendency, Simple Smoothing and Lineal Regression. For this study was elected the first forecast model and its application suggests that: the volume of the compaction solid wastes, aqueous liquids and spent radioactive sources will increase respectively in 152%, 49.8% and 55.7%, while the radioactive organic liquid wastes will diminish in 13.15%. (Author)

  10. Biodegradation of the alkaline cellulose degradation products generated during radioactive waste disposal.

    Science.gov (United States)

    Rout, Simon P; Radford, Jessica; Laws, Andrew P; Sweeney, Francis; Elmekawy, Ahmed; Gillie, Lisa J; Humphreys, Paul N

    2014-01-01

    The anoxic, alkaline hydrolysis of cellulosic materials generates a range of cellulose degradation products (CDP) including α and β forms of isosaccharinic acid (ISA) and is expected to occur in radioactive waste disposal sites receiving intermediate level radioactive wastes. The generation of ISA's is of particular relevance to the disposal of these wastes since they are able to form complexes with radioelements such as Pu enhancing their migration. This study demonstrates that microbial communities present in near-surface anoxic sediments are able to degrade CDP including both forms of ISA via iron reduction, sulphate reduction and methanogenesis, without any prior exposure to these substrates. No significant difference (n = 6, p = 0.118) in α and β ISA degradation rates were seen under either iron reducing, sulphate reducing or methanogenic conditions, giving an overall mean degradation rate of 4.7 × 10(-2) hr(-1) (SE ± 2.9 × 10(-3)). These results suggest that a radioactive waste disposal site is likely to be colonised by organisms able to degrade CDP and associated ISA's during the construction and operational phase of the facility.

  11. Biodegradation of the alkaline cellulose degradation products generated during radioactive waste disposal.

    Directory of Open Access Journals (Sweden)

    Simon P Rout

    Full Text Available The anoxic, alkaline hydrolysis of cellulosic materials generates a range of cellulose degradation products (CDP including α and β forms of isosaccharinic acid (ISA and is expected to occur in radioactive waste disposal sites receiving intermediate level radioactive wastes. The generation of ISA's is of particular relevance to the disposal of these wastes since they are able to form complexes with radioelements such as Pu enhancing their migration. This study demonstrates that microbial communities present in near-surface anoxic sediments are able to degrade CDP including both forms of ISA via iron reduction, sulphate reduction and methanogenesis, without any prior exposure to these substrates. No significant difference (n = 6, p = 0.118 in α and β ISA degradation rates were seen under either iron reducing, sulphate reducing or methanogenic conditions, giving an overall mean degradation rate of 4.7 × 10(-2 hr(-1 (SE ± 2.9 × 10(-3. These results suggest that a radioactive waste disposal site is likely to be colonised by organisms able to degrade CDP and associated ISA's during the construction and operational phase of the facility.

  12. Implementation of stage 3 decommissioning and optimization of radioactive waste generation, Triton facility, France

    International Nuclear Information System (INIS)

    2008-01-01

    The CEA centre of Fontenay-aux-Roses was created in 1946, when the French nuclear energy programme started. Two generations of facilities have been built and operated. The first generation remained operational for 15 years and was dismantled in the late 1950s. It was replaced by a new generation of facilities, as part of the French electronuclear programme, and these included the Triton and Nereide research reactors (hereafter called the Triton facility). In accordance with the CEA strategy and taking into account its urban location, in 1998 the CEA Fontenay-aux-Roses centre decided to launch an extensive cleanup programme to be implemented from 2010 onwards. This included the Stage 3 decommissioning of the Triton facility. In the frame of this decommissioning project, a decommissioning strategy was developed making it possible to optimize the volume of radioactive waste generated

  13. THE EFFECTS OF SWIRL GENERATOR HAVING WINGS WITH HOLES ON HEAT TRANSFER AND PRESSURE DROP IN TUBE HEAT EXCHANGER

    Directory of Open Access Journals (Sweden)

    Zeki ARGUNHAN

    2006-02-01

    Full Text Available This paper examines the effect of turbulance creators on heat transfer and pressure drop used in concentric heat exchanger experimentaly. Heat exchanger has an inlet tube with 60 mm in diameter. The angle of swirl generators wings is 55º with each wing which has single, double, three and four holes. Swirl generators is designed to easily set to heat exchanger entrance. Air is passing through inner tube of heat exhanger as hot fluid and water is passing outer of inner tube as cool fluid.

  14. Residual heat use generated by a 12 kW fuel cell in an electric vehicle heating system

    International Nuclear Information System (INIS)

    Colmenar-Santos, Antonio; Alberdi-Jiménez, Lucía; Nasarre-Cortés, Lorenzo; Mora-Larramona, Joaquín

    2014-01-01

    A diesel or gasoline vehicle heating is produced by the heat of the engine coolant liquid. Nevertheless, electric vehicles, due to the fact that electric motor transform directly electricity into mechanical energy through electromagnetic interactions, do not generate this heat so other method of providing it has to be developed. This study introduces the system developed in a fuel cell electric vehicle (lithium-ion battery – fuel cell) with residual heat use. The fuel cell electric vehicle is driven by a 12 kW PEM (proton exchange membrane) fuel cell. This fuel cell has an operating temperature around 50 °C. The residual heat generated was originally wasted by interaction with the environment. The new developed heating system designed integrates the heat generated by the fuel cell into the heating system of the vehicle, reducing the global energy consumption and improving the global efficiency as well. - Highlights: • Modification of heating system was done by introducing the residual heat from fuel cell. • Maximum heat achieved by the heating radiator of 9.27 kW. • Reduction of the heat dissipation by the fuel cell cooling system 1.5 kW. • Total efficiency improvement of 20% with an autonomy increase of 21 km

  15. Analyses of pebble-bed reactors for the generation of heat for heating purposes

    International Nuclear Information System (INIS)

    Muehlensiep, J.; Fricke, U.; Inhester, K.H.; Kugeler, K.; Phlippen, P.W.; Schmidtlein, P.; Swatoch, R.; Wagner, U.

    1986-10-01

    Marginal conditions are described for the use of a nuclear power reactor for long-distance heat supply in densely populated areas. For the design of the high-temperature heat generating reactor, plant components and possible arrangements are analyzed with consideration to safety and costs. System sizes are reasonably chosen on the basis of analyzed parameters, the paramount design goal being to adequately retain the fission products in the coated particles of the fuel elements, in anticipation of probable accidents. With the help of the data record obtained, a system is designed with a cuboid-shaped core as its characteristic feature; the advantage of the core consists in the fact that it quickly discharges the after-heat outwards even in case of a hypothetical accident. Due to the core shape, it is possible to install heat-exchanging components near the core, and to place the safety rods where they can be very effective in reflector borings. (orig./HP) [de

  16. Modes of heat removal from a heat-generating debris bed

    International Nuclear Information System (INIS)

    Squarer, D.; Hochreiter, L.E.; Piecznski, A.T.

    1984-01-01

    In the worst hypothetical accident in a light water reactor, when all protection systems fail, the core could be converted into a deep particulate bed either in-vessel or ex-vessel. The containment of such an accident depends on the coolability of a heat-generating debris bed. Some recent experimental and analytical studies that are concerned with heat removal from such a particulate bed are reviewed. Studies have indicated that bed dryout flux and, therefore, the heat removal rate from the particulate bed increases with the particle diameter (i.e., the permeability) for pool boiling conditions and can exceed the critical heat flux of a flat plate. Bed dryout in a large particle bed (i.e., a few millimetres) was found to be closely related to the ''flooding'' limit of the bed. Dryout under forced flow conditions was found to be affected by both forced and natural convection for mass flow rate smaller than m /SUB cr/ , whereas above this mass flow rate, bed dryout is proportional to the mass flow rate. Recent analyses were found to be in agreement with experimental data; however, additional research is needed to assess factors not accounted for in previous studies (e.g., effect of pressure, multidimensionality, stratification, etc.). Based on the expected pressure and particle sizes in a postulated severe accident sequence, a debris bed should be coolable, given a sufficient water supply

  17. Characterization of long-lived radioactive dust clouds generated in uranium mill operations

    International Nuclear Information System (INIS)

    Bigu, J.

    1987-01-01

    The characteristics of long-lived radioactive dust clouds generated in several mechanical and physico-chemical operations in a uranium mill have been investigated. The study consisted of the determination of dust size distribution, and of the radionuclides contained in the particles of each dimension class ranging from <0.1 to 26 μm in diameter. Experiments were conducted using several cascade impactors operating at different sample flow rates. Two different types of cascade impactors were used. Radionuclide identification was done using α-spectrometry and γ-spectrometry. Long-lived and short-lived radionuclides were identified in dust samples. The characteristics of the dust clouds depended on the mill operation. The following operations were studied: crushing (vibrating grizzly, jaw crusher, cone crusher); screening; ore transportation; grinding; acid leaching; counter-current decantation; yellowcake precipitation and drying; and yellowcake packaging. In addition, other dust and radioactivity measurements have been carried out

  18. Radioactivity release vs probability for a steam generator tube rupture accident

    International Nuclear Information System (INIS)

    Buslik, A.J.; Hall, R.E.

    1978-01-01

    A calculation of the probability of obtaining various radioactivity releases from a steam generator tube rupture (SGTR) is presented. The only radioactive isotopes considered are Iodine-131 and Xe-133. The particular accident path considered consists of a double-ended guillotine SGTR followed by loss of offsite power (LOSP). If there is no loss of offsite power, and no system fault other than the SGTR, it is judged that the consequences will be minimal, since the amount of iodine released through the condenser air ejector is expected to be quite small; this is a consequence of the fact that the concentration of iodine in the vapor released from the condenser air ejector is very small compared to that dissolved in the condensate water. In addition, in some plants the condenser air ejector flow is automatically diverted to containment or a high-activity alarm. The analysis presented here is for a typical Westinghouse PWR such as described in RESAR-3S

  19. Situation of the radioactive waste management and the employee radiation exposure in commercial power generation reactor facilities in fiscal 1980

    International Nuclear Information System (INIS)

    1981-01-01

    (1) Situation of the radioactive waste management in commercial power generating reactor facilities: The owners of power generation reactor facilities are obligated not to exceed the target dose around the sites by law in the radioactive waste management. The release of radioactive gaseous and liquid wastes and the storage of radioactive solid wastes in respective reactor facilities in fiscal 1980 are presented in tables (for the former, the data since 1971 are also given). The release control values were satisfied in all the facilities. (2) Situation of employe radiation exposure in commercial power generating reactor facilities: The owners of power generation reactor facilities are obligated not to exceed the permissible exposure doses by law. The Employe exposure doses in respective reactor facilities in fiscal 1980 are given in tables. All exposure doses were below the permissible levels. (J.P.N.)

  20. 01 - The sustainable management of radioactive materials with fourth-generation reactors

    International Nuclear Information System (INIS)

    2012-12-01

    This publication first explains the reasons for the development of fourth-generation nuclear systems: the issue of resources, the issue of used fuels, technologies for fast breeder fourth-generation reactors, the alternative of HFC-cooled light water reactors, the potential market for fast-breeder reactors, strategies in different countries. Then, the authors address the strategy development for these fourth-generation reactors: requirements, safety, economic competitiveness, resistance to proliferation, flexible management of nuclear resources, development scheme (sodium or gas-based heat transfer), and fuel cycle. They finally discuss the possible transition scenarios towards this new generation

  1. Reactor type choice and characteristics for a small nuclear heat and electricity co-generation plant

    International Nuclear Information System (INIS)

    Liu Kukui; Li Manchang; Tang Chuanbao

    1997-01-01

    In China heat supply consumes more than 70 percent of the primary energy resource, which makes for heavy traffic and transportation and produces a lot of polluting materials such as NO x , SO x and CO 2 because of use of the fossil fuel. The utilization of nuclear power into the heat and electricity co-generation plant contributes to the global environmental protection. The basic concept of the nuclear system is an integral type reactor with three circuits. The primary circuit equipment is enclosed in and linked up directly with reactor vessel. The third circuit produces steam for heat and electricity supply. This paper presents basic requirements, reactor type choice, design characteristics, economy for a nuclear co-generation plant and its future application. The choice of the main parameters and the main technological process is the key problem of the nuclear plant design. To make this paper clearer, take for example a double-reactor plant of 450 x 2MW thermal power. There are two sorts of main technological processes. One is a water-water-steam process. Another is water-steam-steam process. Compared the two sorts, the design which adopted the water-water-steam technological process has much more advantage. The system is simplified, the operation reliability is increased, the primary pressure reduces a lot, the temperature difference between the secondary and the third circuits becomes larger, so the size and capacity of the main components will be smaller, the scale and the cost of the building will be cut down. In this design, the secondary circuit pressure is the highest among that of the three circuits. So the primary circuit radioactivity can not leak into the third circuit in case of accidents. (author)

  2. Solar heat collector-generator for cooling purposes

    Science.gov (United States)

    Abdullah, K.

    1982-01-01

    The performance of an experimental LiBr-H2O solar collector powered absorption cooling system is described. A numerical model was developed of the energy, mass, and momentum balances across the heat-exchange loop to obtain the refrigerant vapor generation rate. The mechanism works by the thermosiphon principle, which eliminates mechanical devices from the loop. All leaks were fixed before measurements began with a test apparatus comprising a pyrex tube 1.87 m long with a 2.7 i.d. The refrigerant flow rate was monitored, along with temperature changes in the fluid and across the tube. Bubble initiation was observed from the free surface extending downward in the tube. Reynolds numbers varied from 6-43 in the liquid phase and 81-204 in the vapor phase. A formulation was made for the low-velocity two-phase flow and good agreement was demonstrated with the simulation.

  3. The German Final Repository Konrad for Low and Intermediate Level Waste with Negligible Heat Generation - Water Law Issues

    International Nuclear Information System (INIS)

    Boetsch, W.; Grundler, D.; Kugel, K.; Brennecke, P.; Steyer, S.

    2009-01-01

    A survey on the conceptual realization of the requirements due to water law aspects within the license the KONRAD repository for radioactive waste with negligible heat generation in Germany is given [1]. The regulatory decision for the implementation and operation of the repository KONRAD includes, among other things, water law issues. In particular, the KONRAD license includes waste requirements concerning non-radioactive hazardous material (waste package constituents) which have to be considered producing KONRAD waste packages. The intended philosophy of waste acceptance and waste package quality assurance measures to be considered by the KONRAD site operator as well as by the waste producer will be presented. It will demonstrate the selected procedure of the waste declaration and acceptance and describe the structure and logic of tools and aids to comply with the legal requirements of the license and its collateral clause issued under water law. (authors)

  4. Melting method for radioactive solid wastes and device therefor

    Energy Technology Data Exchange (ETDEWEB)

    Komatsu, Masahiko; Abe, Takashi; Nakayama, Junpei; Kusamichi, Tatsuhiko; Sakamoto, Koichi

    1998-11-17

    Upon melting radioactive solid wastes mixed with radioactive metal wastes and non metal materials such as concrete by cold crucible high frequency induction heating, induction coils are wound around the outer circumference of a copper crucible having a water cooling structure to which radioactive solid wastes are charged. A heating sleeve formed by a material which generates heat by an induction heating function of graphite is disposed to the inside of the crucible at a height not in contact with molten metals in the crucible vertically movably. Radioactive solid wastes are melted collectively by the induction heat of the induction coils and thermal radiation and heat conduction of the heating sleeve heated by the induction heat. With such procedures, non metal materials such as concrete and radioactive metal wastes in a mixed state can be melt collectively continuously highly economically. (T.M.)

  5. Radiolytic gas generation from cement-based waste hosts for DOE low-level radioactive wastes

    International Nuclear Information System (INIS)

    Dole, L.R.; Friedman, H.A.

    1986-01-01

    Using cement-based immobilization binders with simulated radioactive waste containing sulfate, nitrate, nitrite, phosphate, and fluoride anions, the gamma- and alpha-radiolytic gas generation factors (G/sub t/, molecules/100 eV) and gas compositions were measured on specimens of cured grouts. These tests studied the effects of; (1) waste composition; (2) the sample surface-to-volume ratio; (3) the waste slurry particle size; and (4) the water content of the waste host formula. The radiolysis test vessels were designed to minimize the ''dead'' volume and to simulate the configuration of waste packages

  6. Structural steels for power generating equipment and heat and chemical heat treatments

    International Nuclear Information System (INIS)

    Astaf'ev, A.A.

    1979-01-01

    Development of structural steels for power generating equipment and for reactor engineering, in particular, is elucidated. Noted is utilization of the 15Kh2NMFA steels for the WWER-1000 reactor vessels, the 10GN2MFA steels for steam generators, pressurizers, vessels of the automatic emergency shut down and safety system; the 00Kh12N3DL steel for cast pump vessels and main locking bars. The recommendations on heat treatment of big forgings, for instance, ensuring the necessary complex of mechanical properties are given. Diffusion chromizing with subsequent nitriding of austenitic steels which increase durability of the components in BN reactors more than 4 times, is practised on a large scale

  7. Specifying the Concept of Future Generations for Addressing Issues Related to High-Level Radioactive Waste.

    Science.gov (United States)

    Kermisch, Celine

    2016-12-01

    The nuclear community frequently refers to the concept of "future generations" when discussing the management of high-level radioactive waste. However, this notion is generally not defined. In this context, we have to assume a wide definition of the concept of future generations, conceived as people who will live after the contemporary people are dead. This definition embraces thus each generation following ours, without any restriction in time. The aim of this paper is to show that, in the debate about nuclear waste, this broad notion should be further specified and to clarify the related implications for nuclear waste management policies. Therefore, we provide an ethical analysis of different management strategies for high-level waste in the light of two principles, protection of future generations-based on safety and security-and respect for their choice. This analysis shows that high-level waste management options have different ethical impacts across future generations, depending on whether the memory of the waste and its location is lost, or not. We suggest taking this distinction into account by introducing the notions of "close future generations" and "remote future generations", which has important implications on nuclear waste management policies insofar as it stresses that a retrievable disposal has fewer benefits than usually assumed.

  8. Analysis of the internal heat losses in a thermoelectric generator

    DEFF Research Database (Denmark)

    Bjørk, Rasmus; Christensen, Dennis Valbjørn; Eriksen, Dan

    2014-01-01

    and radiative heat losses, including surface to surface radiation. For radiative heat losses it is shown that for the temperatures considered here, surface to ambient radiation is a good approximation of the heat loss. For conductive heat transfer the module efficiency is shown to be comparable to the case...... of radiative losses. Finally, heat losses due to internal natural convection in the module is shown to be negligible for the millimetre sized modules considered here. The combined case of radiative and conductive heat transfer resulted in the lowest efficiency. The optimized load resistance is found...... to decrease for increased heat loss. The leg dimensions are varied for all heat losses cases and it is shown that the ideal way to construct a TEG module with minimal heat losses and maximum efficiency is to either use a good insulating material between the legs or evacuate the module completely, and use...

  9. Automatic ID heat load generation in ANSYS code

    International Nuclear Information System (INIS)

    Wang, Zhibi.

    1992-01-01

    Detailed power density profiles are critical in the execution of a thermal analysis using a finite element (FE) code such as ANSYS. Unfortunately, as yet there is no easy way to directly input the precise power profiles into ANSYS. A straight-forward way to do this is to hand-calculate the power of each node or element and then type the data into the code. Every time a change is made to the FE model, the data must be recalculated and reentered. One way to solve this problem is to generate a set of discrete data, using another code such as PHOTON2, and curve-fit the data. Using curve-fitted formulae has several disadvantages. It is time consuming because of the need to run a second code for generation of the data, curve-fitting, and doing the data check, etc. Additionally, because there is no generality for different beamlines or different parameters, the above work must be repeated for each case. And, errors in the power profiles due to curve-fitting result in errors in the analysis. To solve the problem once and for all and with the capability to apply to any insertion device (ID), a program for ED power profile was written in ANSYS Parametric Design Language (APDL). This program is implemented as an ANSYS command with input parameters of peak magnetic field, deflection parameter, length of ID, and distance from the source. Once the command is issued, all the heat load will be automatically generated by the code

  10. A positive (negative) surface ionization source concept for radioactive ion beam generation

    International Nuclear Information System (INIS)

    Alton, G.D.; Mills, G.D.

    1996-01-01

    A novel, versatile, new concept, spherical-geometry, positive (negative) surface-ionization source has been designed and fabricated which will have the capability of generating both positive- and negative-ion beams without mechanical changes to the source. The source utilizes a highly permeable, high-work-function Ir ionizer (φ ≅ 5.29 eV) for ionizing highly electropositive atoms/molecules; while for negative-surface ionization, the work function is lowered by continually feeding a highly electropositive vapor through the ionizer matrix. The use of this technique to effect low work function surfaces for negative ion beam generation has the potential of overcoming the chronic poisoning effects experienced with LaB 6 while enhancing the probability for negative ion formation of atomic and molecular species with low to intermediate electron affinities. The flexibility of operation in either mode makes it especially attractive for radioactive ion beam (RIB) applications and, therefore, the source will be used as a complementary replacement for the high-temperature electron impact ionization sources presently in the use at the Holifield radioactive ion beam facility (HRIBF). The design features and operational principles of the source are described in this report. (orig.)

  11. Radiolytic generation of chloro-organic compounds in transuranic and low-level radioactive waste

    International Nuclear Information System (INIS)

    Reed, D.T.; Armstrong, S.C.; Krause, T.R.

    1993-01-01

    The radiolytic degradation of chloro-plastics is being investigated to evaluate the formation of chlorinated volatile organic compounds in radioactive waste. These chlorinated VOCs, when their subsequent migration in the geosphere is considered, are potential sources of ground-water contamination. This contamination is an important consideration for transuranic waste repositories being proposed for the Waste Isolation Pilot Plant project and the several additional low-level radioactive waste sites being considered throughout the United States. The production of chlorinated volatile organic compounds due to the interaction of ionizing radiation with chloro-plastic materials has been well-established in both this work and past studies. This occurs as a result of gamma, beta, and alpha particle interactions with the plastic material. The assemblage of organic compounds generated depends on the type of plastic material, the type of ionizing radiation, the gaseous environment present and the irradiation temperature. In the authors' experiments, gas generation data were obtained by mounting representative plastics near (3 mm) an alpha particle source (Am-241 foil). This assembly was placed in an irradiation vessel which contained air, nitrogen, or a hydrogen/carbon dioxide mixture, at near-atmospheric pressures, to simulate the range of atmospheres likely to be encountered in the subsurface. The gas phase in the vessels are periodically sampled for net gas production. The gas phase concentrations are monitored over time to determine trends and calculate the radiolytic yield for the various gaseous products

  12. Study of particle size distribution and formation mechanism of radioactive aerosols generated in high-energy neutron fields

    CERN Document Server

    Endo, A; Noguchi, H; Tanaka, S; Iida, T; Furuichi, S; Kanda, Y; Oki, Y

    2003-01-01

    The size distributions of sup 3 sup 8 Cl, sup 3 sup 9 Cl, sup 8 sup 2 Br and sup 8 sup 4 Br aerosols generated by irradiations of argon and krypton gases containing di-octyl phthalate (DOP) aerosols with 45 MeV and 65 MeV quasi-monoenergetic neutrons were measured in order to study the formation mechanism of radioactive particles in high energy radiation fields. The effects of the size distribution of the radioactive aerosols on the size of the added DOP aerosols, the energy of the neutrons and the kinds of nuclides were studied. The observed size distributions of the radioactive particles were explained by attachment of the radioactive atoms generated by the neutron-induced reactions to the DOP aerosols. (author)

  13. Declaration and authorization forms for the fabrication, distribution or use of radioactive sources or electric generators of ionizing radiation

    International Nuclear Information System (INIS)

    2010-01-01

    This document gathers all the forms to be completed when declaring or when asking for an authorization for the fabrication, retailing or use of radioactive sources or electric equipment generating ionizing radiation. These forms can concern all domains (use of sealed radioactive sources, possession and use of a particle accelerator or of radionuclides, import or export of radionuclides or of products containing radionuclides), or the use of such materials or equipment in the medical sector, or the fabrication and use in industry or research, or in user's guides for radioactive sources

  14. Comparison of the heat generation of light curing units.

    Science.gov (United States)

    Bagis, Bora; Bagis, Yildirim; Ertas, Ertan; Ustaomer, Seda

    2008-02-01

    The aim of this study was to evaluate the heat generation of three different types of light curing units. Temperature increases were recorded from a distance of 1 mm from a thermocouple to the tip of three different types of light curing units including one quartz-tungsten halogen (QTH), one plasma arc (PAC), and one light emitting diode (LED) unit. An experimental model was designed to fix the 1 mm distance between the tip of the light curing units and the thermocouple wire. Temperature changes were recorded in 10 second intervals up to 40 seconds. (10, 20, 30, and 40 seconds). Temperature measurements were repeated three times for every light curing unit after a one hour standby period. Statistical analysis of the results was performed using the analysis of variance (ANOVA) and the Bonferroni Test. The highest temperature rises (54.4+/-1.65 degrees C) occurred during activation of a PAC light curing unit for every test period (pdamage to the pulp.

  15. Numerical model to simulate the isotopic and heat release and transport through the geosphere from a geological repository of radioactive wastes

    International Nuclear Information System (INIS)

    Hidalgo Lopez, A.

    2002-01-01

    The aim of this research is to simulate the isotopic and heat release and transport through the geosphere, from a geological repository of high level nuclear waste. in order to achieve it, different physical processes, that have to do with the problem, are considered: groundwater flow, radioactive decay, nuclide dissolution in groundwater, heat generation, mass and heat transport. Some of these phenomena are related among the, which allows to build a coupled model,which is the starting point to generate a FORTRAN code. The flow and transport models are developed in two spatial dimensions and are integrated in space by means of a finite volume method. The time integration is fulfilled by a θ-method. Moreover, the advection-diffusion equation is solved by two finite volume techniques. In the first one a linear interpolation is used whereas in the second it is used a quadratic one. Also, a consistency an stability study of both methods is carried out in order to compare their stability zones and the errors appearing. Stability is analysed by applying the von Neumann method, which is based upon Fourier series. Although it is a classical technique when dealing with finite-difference schemes, it is here applied to two finite volume schemes. (Author)

  16. Gas generation from low-level radioactive waste: Concerns for disposal

    International Nuclear Information System (INIS)

    Siskind, B.

    1992-01-01

    The Advisory Committee on Nuclear Waste (ACNW) has urged the Nuclear Regulatory Commission (NRC) to reexamine the topic of hydrogen gas generation from low-level radioactive waste (LLW) in closed spaces to ensure that the slow buildup of hydrogen from water-bearing wastes in sealed containers does not become a problem for long-term safe disposal. Brookhaven National Laboratory (BNL) has prepared a report, summarized in this paper, for the NRC to respond to these concerns. The paper discusses the range of values for G(H 2 ) reported for materials of relevance to LLW disposal; most of these values are in the range of 0.1 to 0.6. Most studies of radiolytic hydrogen generation indicate a leveling off of pressurization, probably because of chemical kinetics involving, in many cases, the radiolysis of water within the waste. Even if no leveling off occurs, realistic gas leakage rates (indicating poor closure by gaskets on drums and liners) will result in adequate relief of pressure for radiolytic gas generation from the majority of commercial sector LLW packages. Biodegradative gas generation, however, could pose a pressurization hazard even at realistic gas leakage rates. Recommendations include passive vents on LLW containers (as already specified for high integrity containers) and upper limits to the G values and/or the specific activity of the LLW

  17. Radioactive release data from Canadian nuclear generating stations 1872-1987

    International Nuclear Information System (INIS)

    1989-03-01

    All nuclear generating stations emit small quantities of radioactive effluent both into the atmosphere and in the form of liquid effluent, into the adjoining water body, be it river, lake or sea. The purpose of this document is to report on the magnitude of these emissions for each nuclear generating station in Canada and to indicate how these emissions compare with the relevant limitations imposed by the Atomic Energy Control Board as part of its regulatory and licensing program. This report incorporates histograms indicating the annual releases of tritium in air, noble gases, iodine-131, airborne particulates, tritium in water and waterborne gross beta activity for each nuclear generating station. In addition, for Pickering NGS 'A', annual released of carbon-14 are depicted for the years 1986 and 1987. In each case the emission data are compared to the Derived Emission Limit (DEL) in order that the data may be placed in perspective. At present, only Pickering NGS 'A' is required to monitor and report carbon-14 emissions. Environmental monitoring for C-14 is conducted around the Bruce site to determine the environmental impact of its emission and whether effluent monitoring will be necessary in future years. Three nuclear generating stations have been permanently taken out of service during the last few years (Gentilly NGS-1, Douglas Point NGS and NPD NGS). Some small emissions from these sites do still occur, however, due to decontamination and decommissioning operations. (11 tabs., 26 figs.)

  18. Final environmental impact statement. Management of commercially generated radioactive waste. Volume 2. Appendices

    Energy Technology Data Exchange (ETDEWEB)

    1980-10-01

    This EIS analyzes the significant environmental impacts that could occur if various technologies for management and disposal of high-level and transuranic wastes from commercial nuclear power reactors were to be developed and implemented. This EIS will serve as the environmental input for the decision on which technology, or technologies, will be emphasized in further research and development activities in the commercial waste management program. The action proposed in this EIS is to (1) adopt a national strategy to develop mined geologic repositories for disposal of commercially generated high-level and transuranic radioactive waste (while continuing to examine subseabed and very deep hole disposal as potential backup technologies) and (2) conduct a R and D program to develop such facilities and the necessary technology to ensure the safe long-term containment and isolation of these wastes. The Department has considered in this statement: development of conventionally mined deep geologic repositories for disposal of spent fuel from nuclear power reactors and/or radioactive fuel reprocessing wastes; balanced development of several alternative disposal methods; and no waste disposal action. This volume contains appendices of supplementary data on waste management systems, geologic disposal, radiological standards, radiation dose calculation models, related health effects, baseline ecology, socio-economic conditions, hazard indices, comparison of defense and commercial wastes, design considerations, and wastes from thorium-based fuel cycle alternatives. (DMC)

  19. Final environmental impact statement. Management of commercially generated radioactive waste. Volume 2. Appendices

    International Nuclear Information System (INIS)

    1980-10-01

    This EIS analyzes the significant environmental impacts that could occur if various technologies for management and disposal of high-level and transuranic wastes from commercial nuclear power reactors were to be developed and implemented. This EIS will serve as the environmental input for the decision on which technology, or technologies, will be emphasized in further research and development activities in the commercial waste management program. The action proposed in this EIS is to (1) adopt a national strategy to develop mined geologic repositories for disposal of commercially generated high-level and transuranic radioactive waste (while continuing to examine subseabed and very deep hole disposal as potential backup technologies) and (2) conduct a R and D program to develop such facilities and the necessary technology to ensure the safe long-term containment and isolation of these wastes. The Department has considered in this statement: development of conventionally mined deep geologic repositories for disposal of spent fuel from nuclear power reactors and/or radioactive fuel reprocessing wastes; balanced development of several alternative disposal methods; and no waste disposal action. This volume contains appendices of supplementary data on waste management systems, geologic disposal, radiological standards, radiation dose calculation models, related health effects, baseline ecology, socio-economic conditions, hazard indices, comparison of defense and commercial wastes, design considerations, and wastes from thorium-based fuel cycle alternatives

  20. A thermoelectric-conversion power supply system using a strontium heat source of high-level radioactive nuclear waste

    International Nuclear Information System (INIS)

    Chikazawa, Yoshitaka

    2011-01-01

    A thermoelectric-conversion power supply system with radioactive strontium in high-level radioactive waste has been proposed. A combination of Alkali Metal Thermo-Electric Conversion (AMTEC) and a strontium fluoride heat source can provide a compact and long-lived power supply system. A heat source design with strontium fluoride pin bundles with Hastelloy cladding and intermediate copper has been proposed. This design has taken heat transportation into consideration, and, in this regard, the feasibility has been confirmed by a three-dimensional thermal analysis using Star-CD code. This power supply system with an electric output of 1 MW can be arranged in a space of 50 m 2 and approximately 1.1 m height and can be operated for 15 years without refueling. This compact and long-lived power supply is suitable for powering sources for remote places and middle-sized ships. From the viewpoint of geological disposal of high-level waste, the proposed power supply system provides a financial base for strontium-cesium partitioning. That is, a combination of minor-actinide recycling and strontium-cesium partitioning can eliminate a large part of decay heat in high-level waste and thus can save much space for geological disposal. (author)

  1. Thermodynamic performance analysis and algorithm model of multi-pressure heat recovery steam generators (HRSG) based on heat exchangers layout

    International Nuclear Information System (INIS)

    Feng, Hongcui; Zhong, Wei; Wu, Yanling; Tong, Shuiguang

    2014-01-01

    Highlights: • A general model of multi-pressure HRSG based on heat exchangers layout is built. • The minimum temperature difference is introduced to replace pinch point analysis. • Effects of layout on dual pressure HRSG thermodynamic performances are analyzed. - Abstract: Changes of heat exchangers layout in heat recovery steam generator (HRSG) will modify the amount of waste heat recovered from flue gas; this brings forward a desire for the optimization of the design of HRSG. In this paper the model of multi-pressure HRSG is built, and an instance of a dual pressure HRSG under three different layouts of Taihu Boiler Co., Ltd. is discussed, with specified values of inlet temperature, mass flow rate, composition of flue gas and water/steam parameters as temperature, pressure etc., steam mass flow rate and heat efficiency of different heat exchangers layout of HRSG are analyzed. This analysis is based on the laws of thermodynamics and incorporated into the energy balance equations for the heat exchangers. In the conclusion, the results of the steam mass flow rate, heat efficiency obtained for three heat exchangers layout of HRSGs are compared. The results show that the optimization of heat exchangers layout of HRSGs has a great significance for waste heat recovery and energy conservation

  2. Evaluation of piping heat transfer, piping flow regimes, and steam generator heat transfer for the Semiscale Mod-1 isothermal tests

    International Nuclear Information System (INIS)

    French, R.T.

    1975-08-01

    Selected experimental data pertinent to piping heat transfer, transient fluid flow regimes, and steam generator heat transfer obtained during the Semiscale Mod-1 isothermal blowdown test series (Test Series 1) are analyzed. The tests in this first test series were designed to provide counterparts to the LOFT nonnuclear experiments. The data from the Semiscale Mod-1 intact and broken loop piping are evaluated to determine the surface heat flux and average heat transfer coefficients effective during the blowdown transient and compared with well known heat transfer correlations used in the RELAP4 computer program. Flow regimes in horizontal pipe sections are calculated and compared with data obtained from horizontal and vertical densitometers and with an existing steady state flow map. Effects of steam generator heat transfer are evaluated quantitatively and qualitatively. The Semiscale Mod-1 data and the analysis presented in this report are valuable for evaluating the adequacy and improving the predictive capability of analytical models developed to predict system response to piping heat transfer, piping flow regimes, and steam generator heat transfer during a postulated loss-of-coolant accident (LOCA) in a pressurized water reactor (PWR). 16 references. (auth)

  3. An evaluation of analytical heat transfer area with various boiling heat transfer correlations in steam generator thermal sizing

    International Nuclear Information System (INIS)

    Jung, B. R.; Park, H. S.; Chung, D. M.; Baik, S. J.

    1999-01-01

    The computer program SAFE has been used to size and analyze the performance of a steam generator which has two types of heat transfer regions in Korean Standard Nuclear Power Plants (KSNP) and Korean Next Generation Reactor (KNGR) design. The SAFE code calculates the analytical boiling heat transfer area using the modified form of the saturated nucleate pool boiling correlation suggested by Rohsenow. The predicted heat transfer area in the boiling region is multiplied by a constant to obtain a final analytical heat transfer area. The inclusion of the multiplier in the analytical calculation has some disadvantage of loss of complete correlation by the governing heat transfer equation. Several comparative analyses have been performed quantitatively to evaluate the possibility of removing the multiplier in the analytical calculation in the SAFE code. The evaluation shows that the boiling correlation and multiplier used in predicting the boiling region heat transfer area can be replaced with other correlations predicting nearly the same heat transfer area. The removal of multiplier included in the analytical calculation will facilitate a direct use of a set of concerned analytical sizing values that can be exactly correlated by the governing heat transfer equation. In addition this will provide more reasonable basis for the steam generator thermal sizing calculation and enhance the code usability without loss of any validity of the current sizing procedure. (author)

  4. High radioactive heat-producing, economically potential granites around Jodhpur city, Malani Igneous Suite, Northwestern India

    International Nuclear Information System (INIS)

    Shrivastava, K.L.; Prajapat, Tina; Mathur, Anju; Gaur, Virendra; Dadhich; Mamta Chauhan, C.P.; Tripathi, Beena

    2013-01-01

    In the south and southeast periphery of the desert city of Jodhpur, there are pink and grey granite islands in the desert sand at Fitkasni-Rasida and Salawas-Nandanvan areas of Malani Igneous Suite (Neoproterozoic). We are reporting the average heat generation value of 15.33 HGU for first and 8.83 HGU for the second area that is much higher than the average (3.8 HGU) known for the continental crust. The concentration of uranium determined is two to four times higher than the average continental crust and thorium is still higher than U and K. The radioelement concentration (Ur) varies from 25.06 to 27 in the Salawas-Nandanvan granites and 43.73 to 75.81 in Fitkasni-Rasida granites. It clearly indicates a 'hot crust', hence favourable for the formation of mineralization of HFS elements, Nb, Ce, REE, U and Th, which need yet to be explored. (author)

  5. Experience and modeling of radioactivity transport following steam generator tube rupture

    International Nuclear Information System (INIS)

    Hopenfeld, J.

    1985-01-01

    A review of the capabilities of the CITADEL computer code as well as plant experience to project radioactivity releases following a steam generator tube rupture in pressurized-water reactors shows that certain experimental data are needed for reliable offsite dose predictions. This article defines five parameters that are the key for such predictions and discusses the functional dependence of these parameters on various operational variables. The above parameters can be used in conjuction with CITADEL or they can be inserted in the appropriate equations, which then can be programmed conveniently as a subroutine in thermal-hydraulic system codes. A joint Westinghouse Electric Corporation, Electric Power Research Institute, and Nuclear Regulatory Commission program aimed at obtaining the five parameters empirically is described

  6. Radioactive emission data from Canadian nuclear generating stations 1986 to 1995

    International Nuclear Information System (INIS)

    1997-05-01

    All nuclear generating station (NGSs) release small quantities of radioactivity in a controlled manner into both the atmosphere (as gaseous effluents) and adjoining water bodies (as liquid effluents). The purpose of this document is to report on the magnitude of these emissions for each operating NGS in Canada and to indicate how these emissions compare with the relevant limitations imposed by the AECB as part of its regulatory and licensing program. The data show that the levels of emissions of gaseous and liquid effluents from all currently operating NGSs are well below the values mandated by the AECB. In fact, since 1987 no emissions have exceeded 1% of those values. 3 tabs., 46 figs

  7. Geospatial analyses and system architectures for the next generation of radioactive materials risk assessment and routing

    International Nuclear Information System (INIS)

    Ganter, J.H.

    1996-01-01

    This paper suggests that inexorable changes in the society are presenting both challenges and a rich selection of technologies for responding to these challenges. The citizen is more demanding of environmental and personal protection, and of information. Simultaneously, the commercial and government information technologies markets are providing new technologies like commercial off-the-shelf (COTS) software, common datasets, ''open'' GIS, recordable CD-ROM, and the World Wide Web. Thus one has the raw ingredients for creating new techniques and tools for spatial analysis, and these tools can support participative study and decision-making. By carrying out a strategy of thorough and demonstrably correct science, design, and development, can move forward into a new generation of participative risk assessment and routing for radioactive and hazardous materials

  8. Dependable Hydrogen and Industrial Heat Generation from the Next Generation Nuclear Plant

    Energy Technology Data Exchange (ETDEWEB)

    Charles V. Park; Michael W. Patterson; Vincent C. Maio; Piyush Sabharwall

    2009-03-01

    The Department of Energy is working with industry to develop a next generation, high-temperature gas-cooled nuclear reactor (HTGR) as a part of the effort to supply the US with abundant, clean and secure energy. The Next Generation Nuclear Plant (NGNP) project, led by the Idaho National Laboratory, will demonstrate the ability of the HTGR to generate hydrogen, electricity, and high-quality process heat for a wide range of industrial applications. Substituting HTGR power for traditional fossil fuel resources reduces the cost and supply vulnerability of natural gas and oil, and reduces or eliminates greenhouse gas emissions. As authorized by the Energy Policy Act of 2005, industry leaders are developing designs for the construction of a commercial prototype producing up to 600 MWt of power by 2021. This paper describes a variety of critical applications that are appropriate for the HTGR with an emphasis placed on applications requiring a clean and reliable source of hydrogen. An overview of the NGNP project status and its significant technology development efforts are also presented.

  9. Magnetoresistance effect of heat generation in a single-molecular spin-valve

    International Nuclear Information System (INIS)

    Jiang, Feng; Yan, Yonghong; Wang, Shikuan; Yan, Yijing

    2016-01-01

    Based on non-equilibrium Green's functions' theory and small polaron transformation's technology, we study the heat generation by current through a single-molecular spin-valve. Numerical results indicate that the variation of spin polarization degree can change heat generation effectively, the spin-valve effect happens not only in electrical current but also in heat generation when Coulomb repulsion in quantum dot is smaller than phonon frequency and interestingly, when Coulomb repulsion is larger than phonon frequency, the inverse spin-valve effect appears by sweeping gate voltage and is enlarged with bias increasing. The inverse spin-valve effect will induce the unique heat magnetoresistance effect, which can be modulated from heat-resistance to heat-gain by gate voltage easily. - Highlights: • Spin-valve effect of heat generation happens when Coulomb repulsion in quantum dot is less than phonon frequency. • When Coulomb repulsion is larger than phonon frequency, inverse spin-valve effect appears and is enlarged with bias increasing. • The variation of spin polarization degree can change heat generation effectively. • The heat magnetoresistance can be modulated from heat-resistance to heat-gain by gate voltage easily.

  10. From Modules to a Generator: An Integrated Heat Exchanger Concept for Car Applications of a Thermoelectric Generator

    Science.gov (United States)

    Bosch, Henry

    2016-03-01

    A heat exchanger concept for a thermoelectric generator with integrated planar modules for passenger car applications is introduced. The module housings, made of deep drawn stainless steel sheet metal, are brazed onto the exhaust gas channel to achieve an optimal heat transfer on the hot side of the modules. The cooling side consists of winding fluid channels, which are mounted directly onto the cold side of the modules. Only a thin foil separates the cooling media from the modules for an almost direct heat contact on the cooling side. Thermoelectric generators with up to 20 modules made of PbTe and Bi2Te3, respectively, are manufactured and tested on a hot gas generator to investigate electrical power output and performance of the thermoelectric generator. The proof of concept of the light weight heat exchanger design made of sheet metal with integrated modules is positively accomplished.

  11. National profile on commercially generated low-level radioactive mixed waste

    International Nuclear Information System (INIS)

    Klein, J.A.; Mrochek, J.E.; Jolley, R.L.; Osborne-Lee, I.W.; Francis, A.A.; Wright, T.

    1992-12-01

    This report details the findings and conclusions drawn from a survey undertaken as part of a joint US Nuclear Regulatory Commission and US Environmental Protection Agency-sponsored project entitled ''National Profile on Commercially Generated Low-Level Radioactive Mixed Waste.'' The overall objective of the work was to compile a national profile on the volumes, characteristics, and treatability of commercially generated low-level mixed waste for 1990 by five major facility categories-academic, industrial, medical, and NRC-/Agreement State-licensed goverment facilities and nuclear utilities. Included in this report are descriptions of the methodology used to collect and collate the data, the procedures used to estimate the mixed waste generation rate for commercial facilities in the United States in 1990, and the identification of available treatment technologies to meet applicable EPA treatment standards (40 CFR Part 268) and, if possible, to render the hazardous component of specific mixed waste streams nonhazardous. The report also contains information on existing and potential commercial waste treatment facilities that may provide treatment for specific waste streams identified in the national survey. The report does not include any aspect of the Department of Energy's (DOES) management of mixed waste and generally does not address wastes from remedial action activities

  12. National profile on commercially generated low-level radioactive mixed waste

    Energy Technology Data Exchange (ETDEWEB)

    Klein, J.A.; Mrochek, J.E.; Jolley, R.L.; Osborne-Lee, I.W.; Francis, A.A.; Wright, T. [Oak Ridge National Lab., TN (United States)

    1992-12-01

    This report details the findings and conclusions drawn from a survey undertaken as part of a joint US Nuclear Regulatory Commission and US Environmental Protection Agency-sponsored project entitled ``National Profile on Commercially Generated Low-Level Radioactive Mixed Waste.`` The overall objective of the work was to compile a national profile on the volumes, characteristics, and treatability of commercially generated low-level mixed waste for 1990 by five major facility categories-academic, industrial, medical, and NRC-/Agreement State-licensed goverment facilities and nuclear utilities. Included in this report are descriptions of the methodology used to collect and collate the data, the procedures used to estimate the mixed waste generation rate for commercial facilities in the United States in 1990, and the identification of available treatment technologies to meet applicable EPA treatment standards (40 CFR Part 268) and, if possible, to render the hazardous component of specific mixed waste streams nonhazardous. The report also contains information on existing and potential commercial waste treatment facilities that may provide treatment for specific waste streams identified in the national survey. The report does not include any aspect of the Department of Energy`s (DOES) management of mixed waste and generally does not address wastes from remedial action activities.

  13. Radioactive waste assessment using 'minimum waste generation' scenario - summary report March 1984

    International Nuclear Information System (INIS)

    Richardson, J.A.; Goodill, D.R.; Tymons, B.J.

    1984-11-01

    This report describes an assessment of radioactive waste management arisings from a defined nuclear power generation - Scheme 1. Scheme 1 assumes a minimum waste generation scenario with raw waste arisings from 3 main groups; (i) existing and committed commercial reactors; (ii) fuel reprocessing plants, (iii) research, industry and medicine. No decommissioning wastes are considered except for arisings from the final fuel cores from decommissioned reactors. The study uses the SIMULATION2 code which models waste material flows through the system. With a knowledge of the accumulations and average production rates of the raw wastes and their isotopic compositions (or total activities), the rates at which conditioned wastes become available for transportation and disposal are calculated, with specific activity levels. The data bases for the inventory calculations and the assumptions concerning future operation of nuclear facilities were those current in 1983. Both the inventory data and plans for the future of existing nuclear installations have been updated since these calculations were completed. Therefore the results from this assessment do not represent the most up-to-date information available. The report does, however, illustrate the methodology of assessment and indicates the type of information that can be generated. (author)

  14. Radioactive waste assessment using 'moderate growth in nuclear electricity generation' scenario

    International Nuclear Information System (INIS)

    Richardson, J.A.; Goodill, D.R.; Tymons, B.J.

    1985-05-01

    This report describes an assessment of radioactive waste management arisings from a defined nuclear power generation scenario -Scheme 3. Scheme 3 assumes a moderate growth in nuclear generation scenario with raw waste arisings from 3 main groups: (i) existing and committed commercial reactors; (ii) fuel reprocessing plants; (iii) research, industry and medicine. No decommissioning wastes are considered except for arisings from the final fuel cores from decommissioned reactors. The study uses the SIMULATION2 code which models waste material flows through the system. With a knowledge of the accumulations and average production rates of the raw wastes and their isotopic compositions (or total activities), the rates at which conditioned wastes become available for transportation and disposal are calculated, with specific activity levels. The data bases for the inventory calculations and the assumptions concerning future operation of nuclear facilities were those current in 1983. Both the inventory data and plans for the future of existing nuclear installations have been updated since these calculations were completed. Therefore the results from this assessment do not represent the most up-to-date information available. The report does, however, illustrate the methodology of assessment, and indicates the type of information that can be generated. (author)

  15. Underground disposal techniques of radioactive wastes and wind power generation in Europe

    International Nuclear Information System (INIS)

    Mori, Yoshiaki

    2003-01-01

    The 25th business report on foreign survey of electric power civil engineering technology. On the 25th foreign survey held by the Society of Electric Power Civil Engineering, Technology, disposal of high-level radioactive wastes (HLRWs) in Switzerland and Sweden, and wind power generation in Spain and Denmark were focused. As a result, it was found that opalinas clay and calcite under survey and investigation of host rock candidates for disposal of HLRWs are stable rock stratum with extremely low water permeability and without groundwater stream. At present, basic research and concrete disposing method are under advancement through actual scale tests. To obtain peoples' understanding on necessity, safety, cost-sharing, and so on of this business, it is essential to easily and precisely technical contents with high level generation specialty. And, on wind power generation, it is necessary to install wind wheels at a position enough to become maximum in wind energy usable from wind observation data and to maintain the wheel mechanically and electrically. Here were described outlines on the survey with its members and schedules. (G.K.)

  16. Determination of thermal characteristics of combustion products of fire-tube heat generator with flow turbulator

    OpenAIRE

    Lukjanov Alexander V.; Ostapenko Dmitry V.; Basist Dmitry V.

    2014-01-01

    Boiler construction is one of the major industries of any state. The aim is to determine the effect of the turbulator on the intensity of heat transfer in the convective part of the fire-tube heat generator of domestic production. The improvement of convective heating surfaces is one of the ways to increase the energy efficiency of the fire-tube heat generator. Since model of the process of heat transfer of gas flow in the convective tubes is multifactorial and does not have clear analytical ...

  17. 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.

  18. Thermoelectric cooling of microelectronic circuits and waste heat electrical power generation in a desktop personal computer

    International Nuclear Information System (INIS)

    Gould, C.A.; Shammas, N.Y.A.; Grainger, S.; Taylor, I.

    2011-01-01

    Thermoelectric cooling and micro-power generation from waste heat within a standard desktop computer has been demonstrated. A thermoelectric test system has been designed and constructed, with typical test results presented for thermoelectric cooling and micro-power generation when the computer is executing a number of different applications. A thermoelectric module, operating as a heat pump, can lower the operating temperature of the computer's microprocessor and graphics processor to temperatures below ambient conditions. A small amount of electrical power, typically in the micro-watt or milli-watt range, can be generated by a thermoelectric module attached to the outside of the computer's standard heat sink assembly, when a secondary heat sink is attached to the other side of the thermoelectric module. Maximum electrical power can be generated by the thermoelectric module when a water cooled heat sink is used as the secondary heat sink, as this produces the greatest temperature difference between both sides of the module.

  19. Experimental observation of current generation by asymmetrical heating of ions in a tokamak plasma

    International Nuclear Information System (INIS)

    Gahl, J.; Ishihara, O.; Wong, K.L.; Kristiansen, M.; Hagler, M.

    1986-01-01

    The first experimental observation of current generation by asymmetrical heating of ions is reported. Ions were asymmetrically heated by a unidirectional fast Alfven wave launched by a slow wave antenna inside a tokamak. Current generation was detected by measuring the asymmetry of the toroidal plasma current with probes at the top and bottom of the toroidal plasma column

  20. Calculation of radiation heat generation on a graphite reflector side of IAN-R1 Reactor

    International Nuclear Information System (INIS)

    Duque O, J.; Velez A, L.H.

    1987-01-01

    Calculation methods for radiation heat generation in nuclear reactor, based on the point kernel approach are revisited and applied to the graphite reflector of IAN-R1 reactor. A Fortran computer program was written for the determination of total heat generation in the reflector, taking 1155 point in it

  1. Estimation of shutdown heat generation rates in GHARR-1 due to ...

    African Journals Online (AJOL)

    Fission products decay power and residual fission power generated after shutdown of Ghana Research Reactor-1 (GHARR-1) by reactivity insertion accident were estimated by solution of the decay and residual heat equations. A Matlab program code was developed to simulate the heat generation rates by fission product ...

  2. An analytical model for the heat generation in friction stir welding

    DEFF Research Database (Denmark)

    Schmidt, Henrik Nikolaj Blich; Hattel, Jesper; Wert, John

    2004-01-01

    The objective of this work is to establish an analytical model for heat generation by friction stir welding (FSW), based on different assumptions of the contact condition between the rotating tool surface and the weld piece. The material flow and heat generation are characterized by the contact...

  3. Thermal power generation during heat cycle near room temperature

    Science.gov (United States)

    Shibata, Takayuki; Fukuzumi, Yuya; Kobayashi, Wataru; Moritomo, Yutaka

    2018-01-01

    We demonstrate that a sodium-ion secondary battery (SIB)-type thermocell consisting of two types of Prussian blue analogue (PBA) with different electrochemical thermoelectric coefficients (S EC ≡ ∂V/∂T V and T are the redox potential and temperature, respectively) produces electrical energy during heat cycles. The device produces an electrical energy of 2.3 meV/PBA per heat cycle between 295 K (= T L) and 323 K (= T H). The ideal thermal efficiency (η = 1.0%), which is evaluated using the heat capacity (C = 4.16 meV/K) of ideal Na2Co[Fe(CN)6], reaches 11% of the Carnot efficiency (ηth = 8.7%). Our SIB-type thermocell is a promising thermoelectric device that harvests waste heat near room temperature.

  4. Safety measures to address the year 2000 issue at medical facilities which use radiation generators and radioactive materials

    International Nuclear Information System (INIS)

    1999-03-01

    In resolution GC(42)/RES/11 on 'Measures to Address the Year 2000 (Y2K) Issue', adopted on 25 September 1998, the General Conference of the International Atomic Energy Agency (IAEA) - inter alia - urged Member States 'to share information with the Secretariat regarding diagnostic and corrective actions being planned or implemented by operating and regulatory organizations at their ... medical facilities which use radioactive materials to make those facilities Year 2000 ready', encouraged the Secretariat 'within existing resources to act as a clearing-house and central point of contact for Member States to exchange information regarding diagnostic and remediation actions being taken at ... medical facilities which use radioactive materials to make these facilities Year 2000 ready', urged the Secretariat 'to handle the information provided by Member States carefully' and requested the Director General to report to it at its next (1999) regular session on the implementation of that resolution. The IAEA Secretariat convened a group of consultants who met in Vienna from 14 to 18 December 1998 and produced this report. The consultants decided that the report should cover not just 'medical facilities which use radioactive materials' but also medical facilities which, while perhaps not using radioactive materials, use ionizing radiation produced by radiation generators such as accelerators. The reports issued together are: Achieving Year 2000 Readiness: Basic Processes; Safety Measures to Address the Year 2000 Issue at Medical Facilities Which Use Radiation Generators and Radioactive Materials; and Safety Measures to Address the Year 2000 Issue at Radioactive Waste Management Facilities. This report addresses means of dealing with the Y2K problem at medical facilities which use radiation generators and radioactive materials

  5. Single-phase convection heat transfer characteristics of pebble-bed channels with internal heat generation

    International Nuclear Information System (INIS)

    Meng Xianke; Sun Zhongning; Xu Guangzhan

    2012-01-01

    Graphical abstract: The core of the water-cooled pebble bed reactor is the porous channels which stacked with spherical fuel elements. The gaps between the adjacent fuel elements are complex because they are stochastic and often shift. We adopt electromagnetic induction heating method to overall heat the pebble bed. By comparing and analyzing the experimental data, we get the rule of power distribution and the rule of heat transfer coefficient with particle diameter, heat flux density, inlet temperature and working fluid's Re number. Highlights: ► We adopt electromagnetic induction heating method to overall heat the pebble bed to be the internal heat source. ► The ball diameter is smaller, the effect of the heat transfer is better. ► With Re number increasing, heat transfer coefficient is also increasing and eventually tends to stabilize. ► The changing of heat power makes little effect on the heat transfer coefficient of pebble bed channels. - Abstract: The reactor core of a water-cooled pebble bed reactor includes porous channels that are formed by spherical fuel elements. This structure has notably improved heat transfer. Due to the variability and randomness of the interstices in pebble bed channels, heat transfer is complex, and there are few studies regarding this topic. To study the heat transfer characters of pebble bed channels with internal heat sources, oxidized stainless steel spheres with diameters of 3 and 8 mm and carbon steel spheres with 8 mm diameters are used in a stacked pebble bed. Distilled water is used as a refrigerant for the experiments, and the electromagnetic induction heating method is used to heat the pebble bed. By comparing and analyzing the experimental results, we obtain the governing rules for the power distribution and the heat transfer coefficient with respect to particle diameter, heat flux density, inlet temperature and working fluid Re number. From fitting of the experimental data, we obtain the dimensionless average

  6. Regional trends in radiogenic heat generation in the Precambrian basement of the Western Canadian Basin

    Science.gov (United States)

    Jones, F. W.; Majorowicz, J. A.

    Radiogenic heat generation values for 381 basement samples from 229 sites in the western Canadian basin exhibit a lognormal frequency distribution. The mean value = 2.06 (S.D. = 1.22) µWm-3 is larger than the radiogenic heat generation values reported for the shield in the Superior (ca. 1.2 µWm-3, Jessop and Lewis, 1978) and Churchill (ca. 0.7 µWm-3, Drury, 1985) provinces. When equal Log A contour intervals are used to map the basement heat generation, three large zones of relatively high heat generation are found. One coincides with the Peace River Arch basement structure and one with the Athabasca axis (Darnley, 1981). There is no apparent indication of increased heat flow through the Paleozoic formations associated with these two zones. The third zone, in southwestern Saskatchewan, coincides with a high heat flow zone in the Swift Current area. The lack of correlation between heat flow and heat generation in Alberta may be due to the disturbance to the heat flow in the Paleozoic formations by water motion, or may indicate that the heat is from uranium, thorium and potassium isotope enrichment near the basement surface rather than enrichment throughout the entire upper crust.

  7. Heat transfer efficient thermal energy storage for steam generation

    International Nuclear Information System (INIS)

    Adinberg, R.; Zvegilsky, D.; Epstein, M.

    2010-01-01

    A novel reflux heat transfer storage (RHTS) concept for producing high-temperature superheated steam in the temperature range 350-400 deg. C was developed and tested. The thermal storage medium is a metallic substance, Zinc-Tin alloy, which serves as the phase change material (PCM). A high-temperature heat transfer fluid (HTF) is added to the storage medium in order to enhance heat exchange within the storage system, which comprises PCM units and the associated heat exchangers serving for charging and discharging the storage. The applied heat transfer mechanism is based on the HTF reflux created by a combined evaporation-condensation process. It was shown that a PCM with a fraction of 70 wt.% Zn in the alloy (Zn70Sn30) is optimal to attain a storage temperature of 370 deg. C, provided the heat source such as solar-produced steam or solar-heated synthetic oil has a temperature of about 400 deg. C (typical for the parabolic troughs technology). This PCM melts gradually between temperatures 200 and 370 deg. C preserving the latent heat of fusion, mainly of the Zn-component, that later, at the stage of heat discharge, will be available for producing steam. The thermal storage concept was experimentally studied using a lab scale apparatus that enabled investigating of storage materials (the PCM-HTF system) simultaneously with carrying out thermal performance measurements and observing heat transfer effects occurring in the system. The tests produced satisfactory results in terms of thermal stability and compatibility of the utilized storage materials, alloy Zn70Sn30 and the eutectic mixture of biphenyl and diphenyl oxide, up to a working temperature of 400 deg. C. Optional schemes for integrating the developed thermal storage into a solar thermal electric plant are discussed and evaluated considering a pilot scale solar plant with thermal power output of 12 MW. The storage should enable uninterrupted operation of solar thermal electric systems during additional hours

  8. The state of radioactive waste management and of personnel radiation exposure in nuclear power generating facilities in fiscal 1983

    International Nuclear Information System (INIS)

    1985-01-01

    (1) The state of radioactive waste management in nuclear power generating facilities: In the nuclear power stations, the released quantities of radioactive gaseous and liquid wastes are all below the control objective levels. For the respective nuclear power stations, the released quantities of radioactive gaseous and liquid wastes in fiscal 1983 and the objective levels are given in table. And, the quantities of solid wastes taken into storage and the cumulative amounts are given. For reference, the results each year since fiscal 1974 are shown. (2) The state of personnel radiation exposure in nuclear power generating facilities: In the nuclear power stations, the personnel radiation exposures are all below the permissible levels. The dose distribution etc. in the respective nuclear power stations are given in table. For reference, the results each year since fiscal 1974 are shown. (Mori, K.)

  9. Final environmental impact statement. Management of commercially generated radioactive waste. Volume 1 of 3

    Energy Technology Data Exchange (ETDEWEB)

    1980-10-01

    This EIS analyzes the significant environmental impacts that could occur if various technologies for management and disposal of high-level and transuranic wastes from commercial nuclear power reactors were to be developed and implemented. This EIS will serve as the environmental input for the decision on which technology, or technologies, will be emphasized in further research and development activities in the commercial waste management program. The action proposed in this EIS is to (1) adopt a national strategy to develop mined geologic repositories for disposal of commercially generated high-level and transuranic radioactive waste (while continuing to examine subseabed and very deep hole disposal as potential backup technologies) and (2) conduct a R and D program to develop such facilities and the necessary technology to ensure the safe long-term containment and isolation of these wastes. The Department has considered in this statement: development of conventionally mined deep geologic repositories for disposal of spent fuel from nuclear power reactors and/or radioactive fuel reprocessing wastes; balanced development of several alternative disposal methods; and no waste disposal action. This EIS reflects the public review of and comments offered on the draft statement. Included are descriptions of the characteristics of nuclear waste, the alternative disposal methods under consideration, and potential environmental impacts and costs of implementing these methods. Because of the programmatic nature of this document and the preliminary nature of certain design elements assumed in assessing the environmental consequences of the various alternatives, this study has been based on generic, rather than specific, systems. At such time as specific facilities are identified for particular sites, statements addressing site-specific aspects will be prepared for public review and comment.

  10. Final environmental impact statement. Management of commercially generated radioactive waste. Volume 1 of 3

    International Nuclear Information System (INIS)

    1980-10-01

    This EIS analyzes the significant environmental impacts that could occur if various technologies for management and disposal of high-level and transuranic wastes from commercial nuclear power reactors were to be developed and implemented. This EIS will serve as the environmental input for the decision on which technology, or technologies, will be emphasized in further research and development activities in the commercial waste management program. The action proposed in this EIS is to (1) adopt a national strategy to develop mined geologic repositories for disposal of commercially generated high-level and transuranic radioactive waste (while continuing to examine subseabed and very deep hole disposal as potential backup technologies) and (2) conduct a R and D program to develop such facilities and the necessary technology to ensure the safe long-term containment and isolation of these wastes. The Department has considered in this statement: development of conventionally mined deep geologic repositories for disposal of spent fuel from nuclear power reactors and/or radioactive fuel reprocessing wastes; balanced development of several alternative disposal methods; and no waste disposal action. This EIS reflects the public review of and comments offered on the draft statement. Included are descriptions of the characteristics of nuclear waste, the alternative disposal methods under consideration, and potential environmental impacts and costs of implementing these methods. Because of the programmatic nature of this document and the preliminary nature of certain design elements assumed in assessing the environmental consequences of the various alternatives, this study has been based on generic, rather than specific, systems. At such time as specific facilities are identified for particular sites, statements addressing site-specific aspects will be prepared for public review and comment

  11. Quantitative analysis of the radioactive wastes to be generated in the Brazilian nuclear power plants

    International Nuclear Information System (INIS)

    Santos, Jose Mauro Esteves dos

    1979-01-01

    In the nuclear fuel cycle radioactive waste requiring special treatment (processing, transportation and disposal) is produced. For the implementation of a waste management program, parameters such as volume, specific activity, thermal power, gamma power, (alpha,η) and spontaneous fission neutron production rates are required. In this work, we have calculated: a) The specific activity, thermal power, gamma power and neutron production rate for the irradiated fuel of Angra II; b) The volumes of radioactive waste that will be produced in the nuclear fuel cycle in Brazil; c) The specific activity, thermal power, gamma power and neutron production rate for the high-level waste that will be produced during fuel reprocessing. In the short-term it is concluded that the major problems that will require solution will be the disposal of the low-level waste (volume V L ) and the interim storage of the irradiated fuel elements (volume V F ) generated in the nuclear power plants. For the years 1990 and 2010 these volumes are: (1990) V L = 16149 m 3 ; V F = 1287 m 3 and (2010) V L = 690506 m 3 , V F = 55051 m 3 . In the medium-term the problem of the interim storage of the high-level waste (volume V H ) must be solved. The volumes of this waste we have calculated for the years 2000 and 2010 are: (2000) V H = 50 m 3 and (2010) V H = 1265 m 3 . Long term evaluation of high-level waste disposal must be analysed to aid in initial studies of this problem. Several parameters of this waste have been calculated as a function of time after reprocessing. (author)

  12. Numerical Investigation for Strengthening Heat Transfer Mechanism of the Tube-Row Heat Exchanger in a Compact Thermoelectric Generator

    Science.gov (United States)

    Zhang, Zheng; Chen, Zijian; Liu, Hongwu; Yue, Hao; Chen, Dongbo; Qin, Delei

    2018-06-01

    According to the basic principle of heat transfer enhancement, a 1-kW compact thermoelectric generator (TEG) is proposed that is suitable for use at high temperatures and high flow speeds. The associated heat exchanger has a tube-row structure with a guide-plate to control the thermal current. The heat exchanger has a volume of 7 L, and the TEG has a mass of 8 kg (excluding the thermoelectric modules (TEMs)). In this paper, the heat transfer process of the tube-row exchanger is modeled and analyzed numerically; and the influences of its structure on the heat transfer and temperature status of the TEMs are investigated. The results show that use of the thin - wall pipes and increase of surface roughness inside the pipes are effective ways to improve the heat transfer efficiency, obtain the rated surface temperature, and make the TEG compact and lightweight. Furthermore, under the same conditions, the calculated results are compared with the data of a fin heat exchanger. The comparison results show that the volume and mass of the tube-row heat exchanger are 19% and 33% lower than those of the fin type unit, and that the pressure drop is reduced by 16%. In addition, the average temperature in the tube-row heat exchanger is increased by 15°C and the average temperature difference is increased by 19°C; the tube-row TEG has a more compact volume and better temperature characteristics.

  13. Numerical Investigation for Strengthening Heat Transfer Mechanism of the Tube-Row Heat Exchanger in a Compact Thermoelectric Generator

    Science.gov (United States)

    Zhang, Zheng; Chen, Zijian; Liu, Hongwu; Yue, Hao; Chen, Dongbo; Qin, Delei

    2018-04-01

    According to the basic principle of heat transfer enhancement, a 1-kW compact thermoelectric generator (TEG) is proposed that is suitable for use at high temperatures and high flow speeds. The associated heat exchanger has a tube-row structure with a guide-plate to control the thermal current. The heat exchanger has a volume of 7 L, and the TEG has a mass of 8 kg (excluding the thermoelectric modules (TEMs)). In this paper, the heat transfer process of the tube-row exchanger is modeled and analyzed numerically; and the influences of its structure on the heat transfer and temperature status of the TEMs are investigated. The results show that use of the thin - wall pipes and increase of surface roughness inside the pipes are effective ways to improve the heat transfer efficiency, obtain the rated surface temperature, and make the TEG compact and lightweight. Furthermore, under the same conditions, the calculated results are compared with the data of a fin heat exchanger. The comparison results show that the volume and mass of the tube-row heat exchanger are 19% and 33% lower than those of the fin type unit, and that the pressure drop is reduced by 16%. In addition, the average temperature in the tube-row heat exchanger is increased by 15°C and the average temperature difference is increased by 19°C; the tube-row TEG has a more compact volume and better temperature characteristics.

  14. Critical heat flux and transition boiling characteristics for a sodium-heated steam generator tube for LMFBR applications

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, S.; Holmes, D.H.

    1977-04-01

    An experimental program was conducted to characterize critical heat flux (CHF) in a sodium-heated steam generator tube model at a proposed PLBR steam generator design pressure of 7.2 MPa. Water was circulated vertically upward in the tube and the heating sodium was flowing counter-current downward. The experimental ranges were: mass flux, 110 to 1490 kg/s.m/sup 2/ (0.08 to 1.10 10/sup 6/ lbm/h.ft/sup 2/); critical heat flux, 0.16 to 1.86 MW/m/sup 2/ (0.05 to 0.59 10/sup 6/ Btu/h.ft/sup 2/); and critical quality, 0.48 to 1.0. The CHF phenomenon for the experimental conditions is determined to be dryout as opposed to departure from nucleate boiling (DNB). The data are divided into high- and low-mass flux regions.

  15. Future aspects for liquid metal heated steam generators

    International Nuclear Information System (INIS)

    Jansing, W.; Ratzel, W.; Vinzens, K.

    1975-01-01

    The present status of steam generators is shown. The experience gained until now is expressed in form of basic points. The most important design criteria for steam generator systems are outlined. On the basis of these design criteria, two possible steam generator concepts are shown. Costs in relationship to the repair concepts of two modular steam generators (thermal output 156 and 625 MW) and a pool design of 625 MW are compared. (author)

  16. Future aspects for liquid metal heated steam generators

    Energy Technology Data Exchange (ETDEWEB)

    Jansing, W; Ratzel, W; Vinzens, K

    1975-07-01

    The present status of steam generators is shown. The experience gained until now is expressed in form of basic points. The most important design criteria for steam generator systems are outlined. On the basis of these design criteria, two possible steam generator concepts are shown. Costs in relationship to the repair concepts of two modular steam generators (thermal output 156 and 625 MW) and a pool design of 625 MW are compared. (author)

  17. Great Meteor East (distal Madeira Abyssal Plain): geological studies of its suitability for disposal of heat-emitting radioactive wastes

    International Nuclear Information System (INIS)

    Searle, R.C.; Schultheiss, P.J.; Weaver, P.P.E.; Noel, M.; Kidd, R.B.; Jacobs, C.L.; Huggett, Q.J.

    1985-01-01

    This report summarises geological and geophysical studies carried out by the Institute of Oceanographic Sciences up to December 1983 in an area of the Madeira Abyssal Plain in order to assess its suitability for the disposal of heat-emitting radioactive waste. The results of work carried out in the same area by the Rijks Geologische Dienst of the Netherlands are also reviewed in the report. Other oceanographic studies in the area in the fields of geochemistry, biology and oceanography are briefly touched upon. (author)

  18. Management of Discharge of Low Level Liquid Radioactive Waste Generated in Medical, Educational, Research and Industrial Facilities

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-07-15

    Although published information on management technologies suitable for radioactive effluents is readily available, smaller facilities such as hospitals, universities and research laboratories in some countries can benefit from more detailed guidance on identifying optimal arrangements for effectively managing their radioactive liquid effluents. A wide range of circumstances exist globally, given that the generation of radioactive liquid effluents may be regular or irregular, and the liquid effluents may be suitable for direct discharge to the environment, or may require a period of decay storage prior to discharge. Countries typically fit into one of the four following categories with respect to the status of their arrangements for the management of radioactive liquid effluents: (1) The country does not have sufficient technical, regulatory and organizational infrastructure to effectively manage its radioactive liquid effluents; (2) The country's technical infrastructure for effectively managing its radioactive liquid effluents is almost sufficient, but it is not supported by an acceptable level of regulatory and organizational capacity (e.g. legal infrastructure, administrative infrastructure); (3) The country has sufficient technical, regulatory and organizational capacity, but it is known that the application of the requirements for proper management of radioactive liquid effluents is, in many cases, not being carried out to the standard indicated by official reports; (4) The country has well developed and established regulatory and organizational capacity, which is complemented by an acceptable level of relevant technical infrastructure such that the radioactive liquid effluents can be properly managed. Facilities, as well as countries, in the first three categories will find information in this publication to assist their further development. Even countries that already have the necessary infrastructure to properly manage their liquid radioactive effluents may

  19. Management of Discharge of Low Level Liquid Radioactive Waste Generated in Medical, Educational, Research and Industrial Facilities

    International Nuclear Information System (INIS)

    2013-07-01

    Although published information on management technologies suitable for radioactive effluents is readily available, smaller facilities such as hospitals, universities and research laboratories in some countries can benefit from more detailed guidance on identifying optimal arrangements for effectively managing their radioactive liquid effluents. A wide range of circumstances exist globally, given that the generation of radioactive liquid effluents may be regular or irregular, and the liquid effluents may be suitable for direct discharge to the environment, or may require a period of decay storage prior to discharge. Countries typically fit into one of the four following categories with respect to the status of their arrangements for the management of radioactive liquid effluents: (1) The country does not have sufficient technical, regulatory and organizational infrastructure to effectively manage its radioactive liquid effluents; (2) The country's technical infrastructure for effectively managing its radioactive liquid effluents is almost sufficient, but it is not supported by an acceptable level of regulatory and organizational capacity (e.g. legal infrastructure, administrative infrastructure); (3) The country has sufficient technical, regulatory and organizational capacity, but it is known that the application of the requirements for proper management of radioactive liquid effluents is, in many cases, not being carried out to the standard indicated by official reports; (4) The country has well developed and established regulatory and organizational capacity, which is complemented by an acceptable level of relevant technical infrastructure such that the radioactive liquid effluents can be properly managed. Facilities, as well as countries, in the first three categories will find information in this publication to assist their further development. Even countries that already have the necessary infrastructure to properly manage their liquid radioactive effluents may

  20. Heat generation in lithium/thionyl chloride batteries

    Energy Technology Data Exchange (ETDEWEB)

    Gibbard, H.F.

    1980-01-01

    The flow of heat from lithium/thionyl chloride batteries has been measured in two conduction calorimeters. Several types of cells have been studied, both at rest and during low- and high-rate discharge. In contrast with other reports in the literature, no conditions were found under which the discharge of lithium/thionyl chloride batteries was endothermic. Results at low currents, which are described in terms of the thermodynamic formalism developed previously, are consistent with measurements of the temperature dependence of the open-circuit potential. Cells discharged at higher currents produced more heat flux than predicted by the simple thermodynamic treatment. The current and time variation of the additional heat is consistent with a current-dependent corrosion of the lithium electrode. 14 refs.

  1. The development of a thermoelectric power generator dedicated to stove-fireplaces with heat accumulation systems

    International Nuclear Information System (INIS)

    Sornek, Krzysztof; Filipowicz, Mariusz; Rzepka, Kamila

    2016-01-01

    Highlights: • Application of thermoelectric generators in the stove-fireplace with accumulation. • Construction of the thermoelectric generator is limited by the heat accumulation. • Variants of the heat exchanger’s construction are discussed. • The control method is related on velocity of flue gas and water cooling. • The power limit of 30 W for self-sufficient operation is sufficient. - Abstract: A significant part of the world’s population (about 40%) cooks their meals and provides heating for their homes using wood-burning heating devices. Due to the relatively low cost of fuel and their aesthetic design, solid fuel stoves capable of heat accumulation are convenient and common. The use of dedicated small-scale power generators provides also additional benefits. This paper presents the results of a study conducted to verify the possibility of generating power using stove-fireplaces with heat accumulation systems. In such units, the temperature of the flue gas should be kept at a certain level for the purposes of storing heat, which results from certain limitations of the thermoelectric generators. To verify the possibility of applying thermoelectric modules in such heating devices, a dedicated system with thermoelectric generators was selected from among various microcogeneration systems and implemented. Three types of heat exchangers were studied and the most efficient unit was selected for further testing. Two types of generators, with maximum operating temperatures of 320 and 175 °C, were compared. Subsequently, the characteristics of the latter were determined. The conducted tests allowed to determine the performance and the total efficiency of the generators that were used. It has been demonstrated that the maximum power of the generator would not exceed ca. 30 W e and that there is no economic justification for such a device. However, providing a self-powered and self-sufficient operation of stove-fireplaces with heat accumulation systems

  2. Analysis of Decay Heat Removal by Natural Convection in LMR with a Combined Steam Generator

    International Nuclear Information System (INIS)

    Kim, Eui Kwang; Eoh, Jae Hyuk; Han, Ji Woong; Lee, Tae Ho

    2011-01-01

    Liquid metal reactors (LMRs) conventionally employ an intermediate heat transport system (IHTS) to protect the nuclear core during a sodium-water reaction (SWR) event. However these SWR-related components increase plant construction costs. In order to eliminate the need for an IHTS, a combined steam generator, which is an integrated heat exchanger of a steam generator and intermediate heat exchanger (IHX), was proposed by the Korea Atomic Energy Research Institute (KAERI). The objective of this work is to analyze the natural circulation heat removal capability of the rector system using a combined steam generator. As a means of decay heat removal, a normal heat transport path is composed of a primary sodium system, intermediate lead-bismuth circuit combined with SG and steam/water system. This paper presents the results of the possible temperature and natural circulation flows in all circuits during a steady state for a given reactor power level varied as a function of time

  3. Layout of an internally heated gas generator for the steam gasification of coal

    International Nuclear Information System (INIS)

    Feistel, P.P.; Duerrfeld, R.; Heck, K.H. van; Juentgen, H.

    1975-01-01

    Industrial-scale steam gasification of coal using heat from high temperature reactors requires research and development on allothermal gas generators. Bergbau-Forschung GmbH, Essen, does theoretical and experimental work in this field. The experiments deal with reaction kinetics, heat transfer and material tests. Their significance for the layout of a full-scale gas generator is shown. Including material specifications, the feasibility of a gasifier, characterized by a fluid bed volume of 318 m 3 and a heat transferring area of 4000 m 2 , results. The data, now available, are used to determine the gasification throughput from the heat balance, i.e. the equality of heat consumed and heat transferred. Throughputs of about 50 t/hr of coal are possible for a single gas generator, the helium outlet temperature of the HTR being 950 0 C/ Bergbau-Forschung has commissioned a medium-scale pilot plant (200 kg/hr). (Auth.)

  4. Effects of Fluid Directions on Heat Exchange in Thermoelectric Generators

    DEFF Research Database (Denmark)

    Suzuki, Ryosuke; Sasaki, Yuto; Fujisaka, Takeyuki

    2012-01-01

    Thermal fluids can transport heat to the large surface of a thermoelectric (TE) panel from hot and/or cold sources. The TE power thus obtainable was precisely evaluated using numerical calculations based on fluid dynamics and heat transfer. The commercial software FLUENT was coupled with a TE model...... for this purpose. The fluid velocity distribution and the temperature profiles in the fluids and TE modules were calculated in two-dimensional space. The electromotive force was then evaluated for counter-flow and split-flow models to show the effect of a stagnation point. Friction along the fluid surface along...

  5. Large-Scale Combined Heat and Power (CHP) Generation at Loviisa Nuclear Power Plant Unit 3

    International Nuclear Information System (INIS)

    Bergroth, N.

    2010-01-01

    Fortum has applied for a Decision in Principle concerning the construction of a new nuclear power plant unit (Loviisa 3) ranging from 2800-4600 MWth at its site located at the southern coast of Finland. An attractive alternative investigated is a co-generation plant designed for large-scale district heat generation for the Helsinki metropolitan area that is located approximately 75 km west of the site. The starting point is that the district heat generation capacity of 3 unit would be around 1 000 MWth.The possibility of generating district heat for the metropolitan area by Loviisa's two existing nuclear power plant units was investigated back in the 1980s, but it proved unpractical at the time. With the growing concern of the climate change and the subsequent requirements on heat and power generation, the idea is much more attractive today, when recognising its potential to decrease Finland's carbon dioxide emissions significantly. Currently the district heat generation in metropolitan area is based on coal and natural gas, producing some five to seven million tonnes of carbon dioxide emissions annually. Large-scale combined heat and power (CHP) generation at the 3 unit could cut this figure by up to four million tonnes. This would decrease carbon dioxide emissions by as much as six percent. In addition, large-scale CHP generation would increase the overall efficiency of the new unit significantly and hence, reduce the environmental impact on the local marine environment by cutting heat discharges into the Gulf of Nuclear energy has been used for district heating in several countries both in dedicated nuclear heating plants and in CHP generation plants. However, the heat generation capacity is usually rather limited, maximum being around 250 MWth per unit. Set against this, the 3 CHP concept is much more ambitious, not only because of the much larger heat generation output envisaged, but also because the district heating water would have to be transported over a

  6. Storage depot for radioactive material

    International Nuclear Information System (INIS)

    Szulinski, M.J.

    1983-01-01

    Vertical drilling of cylindrical holes in the soil, and the lining of such holes, provides storage vaults called caissons. A guarded depot is provided with a plurality of such caissons covered by shielded closures preventing radiation from penetrating through any linear gap to the atmosphere. The heat generated by the radioactive material is dissipated through the vertical liner of the well into the adjacent soil and thus to the ground surface so that most of the heat from the radioactive material is dissipated into the atmosphere in a manner involving no significant amount of biologically harmful radiation. The passive cooling of the radioactive material without reliance upon pumps, personnel, or other factor which might fail, constitutes one of the most advantageous features of this system. Moreover this system is resistant to damage from tornadoes or earthquakes. Hermetically sealed containers of radioactive material may be positioned in the caissons. Loading vehicles can travel throughout the depot to permit great flexibility of loading and unloading radioactive materials. Radioactive material can be shifted to a more closely spaced caisson after ageing sufficiently to generate much less heat. The quantity of material stored in a caisson is restricted by the average capacity for heat dissipation of the soil adjacent such caisson

  7. Dynamic study of steam generation from low-grade waste heat in a zeolite–water adsorption heat pump

    International Nuclear Information System (INIS)

    Xue, Bing; Meng, Xiangrui; Wei, Xinli; Nakaso, Koichi; Fukai, Jun

    2015-01-01

    A novel zeolite–water adsorption heat pump system based on a direct-contact heat exchange method to generate steam from low-grade waste gas and water has been proposed and examined experimentally. Superheated steam (200 °C, 0.1 MPa) is generated from hot water (70–80 °C) and dry air (100–130 °C). A dynamic model for steam generation process is developed to describe local mass and heat transfer. This model features a three-phase calculation and a moving water–gas interface. The calculations are carried out in the zeolite–water and zeolite–gas regions. Model outputs are compared with experimental results for validation. The thermal response inside the reactor and mass of steam generated is well predicted. Numerical results show that preheat process with low-temperature steam is an effective method to achieve local equilibrium quickly, thus generation process is enhanced by prolonging the time and increasing mass of the generated steam. Besides, high-pressure steam generation up to 0.5 MPa is possible from the validated dynamic model. Future work could be emphasized on enhancing high-pressure steam generation with preheat process or mass recovery operation

  8. Physical model of the dispersion of a radioactive contaminant in the atmosphere above a heat island

    International Nuclear Information System (INIS)

    Toly, J.A.; Tenchine, D.

    1984-01-01

    The project deals with the impact of surface heating in urban areas on the dispersion of contaminants in the atmosphere. - The atmospheric boundary layer is simulated in a water flume. Ground heating is applied locally reproducing the heat flux of an urban region. Fission products for which internal heat source is neglected are simulated by horizontal plumes at pHs different from the original pH of the flume. - The main results of the study concern: the characterization of the internal boundary layer downstream of the leading edge of the heated ground; the comparison of the concentration distributions of pollutants with and without surface heating. - A transposition of the results, expressed in terms of global parameters, enables information on the heat island effect due to urban regions on the dispersion of contaminants in the atmosphere to be obtained

  9. Experimental studies of parameters affecting the heat generation in friction stir welding process

    Directory of Open Access Journals (Sweden)

    Mijajlović Miroslav M.

    2012-01-01

    Full Text Available Heat generation is a complex process of transformation of a specific type of energy into heat. During friction stir welding, one part of mechanical energy delivered to the welding tool is consumed in the welding process, another is used for deformational processes etc., and the rest of the energy is transformed into heat. The analytical procedure for the estimation of heat generated during friction stir welding is very complex because it includes a significant number of variables and parameters, and many of them cannot be fully mathematically explained. Because of that, the analytical model for the estimation of heat generated during friction stir welding defines variables and parameters that dominantly affect heat generation. These parameters are numerous and some of them, e. g. loads, friction coefficient, torque, temperature, are estimated experimentally. Due to the complex geometry of the friction stir welding process and requirements of the measuring equipment, adequate measuring configurations and specific constructional solutions that provide adequate measuring positions are necessary. This paper gives an overview of the process of heat generation during friction stir welding, the most influencing parameters on heat generation, constructional solutions for the measuring equipment needed for these experimental researches and examples of measured values.

  10. Transfer of radioactive waste disposal knowledge to future generations: A stiff challenge for universities

    International Nuclear Information System (INIS)

    Sabet, B.B.; Elorza, F.J.

    2007-01-01

    Full text: In general, effective knowledge management strategies rely on the capacity to perform a full range of allied functions, among which education and research are the key components. However, in most countries and notably in Europe, universities which have to conduct leading-edge research and to supply society with future skilled staffs on radioactive waste disposal, suffer from both the shortage of the institutional national support and the decline of interest among students. This paper gives an overview of the academic educational challenges in geological disposal of radioactive waste. Prior to presenting possible solutions to overcome difficulties encountered in this field, the causes of the present failure that seriously threaten the future provision of human resources are identified and analysed. Some of the main findings are: The poor image of nuclear issues in general and the lack of public confidence in the management and disposal of radioactive waste in particular; The smallness of the radwaste community and the narrowness of the job market at the national level; The organisational structure of most universities that inhibits partnerships with non-academic institutions and impedes collaborative activities; The reticence of most governments to invest public funds in the academic education on radwaste disposal. These particular motives added to the common problems shared by the whole nuclear sector such as the lack of educational programmes, the ageing of teachers, and the decline in academic R and D activities, bring about the need for collaborative actions. The paper gives an example of possible solutions through the development of a European academic initiative. In response to the rising alarm about the future shortage of expertise, EURATOM has launched the ENEN II (European Commission 6th FP project No. FP6-036414 for years 2007-2008) project. The goal of this project is to consolidate the European nuclear education, training and knowledge

  11. Heat generation rates in lithium thionyl chloride cells

    Science.gov (United States)

    Frank, H.

    1982-03-01

    An empirical equation that is useful for good first approximation in thermal modeling is presented. Indications and measurements of electrochemical heat effects were investigated. The particular cells of interest are of the D size, with spiral wound configuration and were instrumented with a thermocouple. It is found that cathode limited cells can explode on reversal at moderate temperatures.

  12. Smart energy systems and 4th generation district heating

    DEFF Research Database (Denmark)

    Østergaard, Poul Alberg; Lund, Henrik; Mathiesen, Brian Vad

    2016-01-01

    of Sustainable Energy Planning and Management. The editorial and the volume presents work on district heating system scenarios in Austria, grid optimisation using genetic algorithms and finally design of energy scenarios for the Italian Alpine town Bressanone-Brixen from a smart energy approach. © 2016, Aalborg...

  13. Barriers of repository under the conditions of underground isolation of heat releasing radioactive waste in permafrost

    International Nuclear Information System (INIS)

    Kazakov, A.N.; Fedorovich, L.N.

    1995-01-01

    The main positions and the leading principle of the ensuring of the environmental safety of the method of the underground isolation of radioactive waste in permafrost rock are presented in this work and it is shown here the peculiarities in realization of the principle of the multibarrier protection. It is substantiated here the principle of the optimal time of the capacity for work of the repository's engineered barriers. The possibility of the exclusion of the radionuclides migration beyond the working volume of the repository during the time of the potential danger of radioactive waste is also substantiated in these papers

  14. Improvement of the decay heat removal characteristics of the generation IV gas-cooled fast reactor

    International Nuclear Information System (INIS)

    Epiney, A.S.

    2010-01-01

    Gas cooling in nuclear power plants (NPPs) has a long history, the corresponding reactor types developed in France, the UK and the US having been thermal neutron spectrum systems using graphite as the moderator. The majority of NPPs worldwide, however, are currently light water reactors, using ordinary water as both coolant and moderator. These NPPs - of the so-called second generation - will soon need replacement, and a third generation is now being made available, offering increased safety while still based on light water technology. For the longer-term future, viz. beyond the year 2030, R and D is currently ongoing on Generation IV NPPs, aimed at achieving closure of the nuclear fuel cycle, and hence both drastically improved utilization of fuel resources and minimization of long-lived radioactive wastes. Like the SFR, the GFR is an efficient breeder, also able to work as iso-breeder using simply natural uranium as feed and producing waste which is predominantly in the form of fission products. The main drawback of the GFR is the difficulty to evacuate decay heat following a loss-of-coolant accident (LOCA) due to the low thermal inertia of the core, as well as to the low coolant density. The present doctoral research focuses on the improvement of decay heat removal (DHR) for the Generation-IV GFR. The reference GFR system design considered in the thesis is the 2006 CEA concept, with a power of 2400 MWth. The CEA 2006 DHR strategy foresees, in all accidental cases (independent of the system pressure), that the reactor is shut down. For high pressure events, dedicated DHR loops with blowers and heat exchangers are designed to operate when the power conversion system cannot be used to provide acceptable core temperatures under natural convection conditions. For de-pressurized events, the strategy relies on a dedicated small containment (called the guard containment) providing an intermediate back-up pressure. The DHR blowers, designed to work under these pressure

  15. Radiant-heat spray-calcination process for the solid fixation of radioactive waste. Part 1, Non-radioactive pilot unit

    Energy Technology Data Exchange (ETDEWEB)

    Allemann, R.T.; Johnson, B.M. Jr.

    1960-11-14

    The fixation of radioactive waste in a stable solid media by means of calcination of these aqueous solutions has been the subject of considerable-effort throughout the U. S. Atomic Energy Commission and by atomic energy organizations in other countries. Several methods of doing this on a continuous or semi-continuous basis have been devised, and a fev have been demonstrated to be feasible for the handling of non-radioactive, or low-activity, simulated wastes. Notable among methods currently under development are: (a) batch-operated pot calcination of waste generated from reprocessing stainless steel clad fuel elements (Darex process) and Purex waste, (b) combination rotary kiln and ball mill calcination of aluminum nitrate (TBP-25 and Redox process), and (c) fluidized bed calcination of TBP-25 and Purex wastes. Although a considerable amount of engineering experience has been obtained on the calcination of dissolved salts in a fluidized bed, and the other methods have been the subjects of a great deal of study, none of them have been developed to-the extent which would rule out the desirability of further investigation of other possible methods of calcination.

  16. Criteria for selection of target materials and design of high-efficiency-release targets for radioactive ion beam generation

    CERN Document Server

    Alton, G D; Liu, Y

    1999-01-01

    In this report, we define criteria for choosing target materials and for designing, mechanically stable, short-diffusion-length, highly permeable targets for generation of high-intensity radioactive ion beams (RIBs) for use at nuclear physics and astrophysics research facilities based on the ISOL principle. In addition, lists of refractory target materials are provided and examples are given of a number of successful targets, based on these criteria, that have been fabricated and tested for use at the Holifield Radioactive Ion Beam Facility (HRIBF).

  17. Quantity, Quality, and Availability of Waste Heat from United States Thermal Power Generation.

    Science.gov (United States)

    Gingerich, Daniel B; Mauter, Meagan S

    2015-07-21

    Secondary application of unconverted heat produced during electric power generation has the potential to improve the life-cycle fuel efficiency of the electric power industry and the sectors it serves. This work quantifies the residual heat (also known as waste heat) generated by U.S. thermal power plants and assesses the intermittency and transport issues that must be considered when planning to utilize this heat. Combining Energy Information Administration plant-level data with literature-reported process efficiency data, we develop estimates of the unconverted heat flux from individual U.S. thermal power plants in 2012. Together these power plants discharged an estimated 18.9 billion GJ(th) of residual heat in 2012, 4% of which was discharged at temperatures greater than 90 °C. We also characterize the temperature, spatial distribution, and temporal availability of this residual heat at the plant level and model the implications for the technical and economic feasibility of its end use. Increased implementation of flue gas desulfurization technologies at coal-fired facilities and the higher quality heat generated in the exhaust of natural gas fuel cycles are expected to increase the availability of residual heat generated by 10.6% in 2040.

  18. Thermodynamic optimization of ground heat exchangers with single U-tube by entropy generation minimization method

    International Nuclear Information System (INIS)

    Li Min; Lai, Alvin C.K.

    2013-01-01

    Highlights: ► A second-law-based analysis is performed for single U-tube ground heat exchangers. ► Two expressions for the optimal length and flow velocity are developed for GHEs. ► Empirical velocities of GHEs are large compared to thermodynamic optimum values. - Abstract: This paper investigates thermodynamic performance of borehole ground heat exchangers with a single U-tube by the entropy generation minimization method which requires information of heat transfer and fluid mechanics, in addition to thermodynamics analysis. This study first derives an expression for dimensionless entropy generation number, a function that consists of five dimensionless variables, including Reynolds number, dimensionless borehole length, scale factor of pressures, and two duty parameters of ground heat exchangers. The derivation combines a heat transfer model and a hydraulics model for borehole ground heat exchangers with the first law and the second law of thermodynamics. Next, the entropy generation number is minimized to produce two analytical expressions for the optimal length and the optimal flow velocity of ground heat exchangers. Then, this paper discusses and analyzes implications and applications of these optimization formulas with two case studies. An important finding from the case studies is that widely used empirical velocities of circulating fluid are too large to operate ground-coupled heat pump systems in a thermodynamic optimization way. This paper demonstrates that thermodynamic optimal parameters of ground heat exchangers can probably be determined by using the entropy generation minimization method.

  19. Testing for cross-subsidisation in the combined heat and power generation sector

    DEFF Research Database (Denmark)

    Amundsen, Eirik S; Andersen, Per; Jensen, Frank

    2011-01-01

    In this paper we examine cross-subsidisation among combined heat and power producers in Denmark.Information on stand-alone costs for heat generation allows us to empirically compare the Faulhaber tests,tests with an upper bound on stand-alone costs (the Palmer tests) and the fully distributed cos...... test (FDC). All tests indicate a substantial amount of cross-subsidisation from heat generation to power generation. It is shown that the FDC test is closer to that of the Faulhaber tests in its results than the Palmer tests. Thus as the Faulhaber tests are considered in the literature...

  20. Experimental and computational study on thermoelectric generators using thermosyphons with phase change as heat exchangers

    International Nuclear Information System (INIS)

    Araiz, M.; Martínez, A.; Astrain, D.; Aranguren, P.

    2017-01-01

    Highlights: • Thermosyphon with phase change heat exchanger computational model. • Construction and experimentation of a prototype. • ±9% of maximum deviation from experimental values of the main outputs. • Influence of the auxiliary equipment on the net power generation. - Abstract: An important issue in thermoelectric generators is the thermal design of the heat exchangers since it can improve their performance by increasing the heat absorbed or dissipated by the thermoelectric modules. Due to its several advantages, compared to conventional dissipation systems, a thermosyphon heat exchanger with phase change is proposed to be placed on the cold side of thermoelectric generators. Some of these advantages are: high heat-transfer rates; absence of moving parts and lack of auxiliary consumption (because fans or pumps are not required); and the fact that these systems are wickless. A computational model is developed to design and predict the behaviour of this heat exchangers. Furthermore, a prototype has been built and tested in order to demonstrate its performance and validate the computational model. The model predicts the thermal resistance of the heat exchanger with a relative error in the interval [−8.09; 7.83] in the 95% of the cases. Finally, the use of thermosyphons with phase change in thermoelectric generators has been studied in a waste-heat recovery application, stating that including them on the cold side of the generators improves the net thermoelectric production by 36% compared to that obtained with finned dissipators under forced convection.

  1. Updated Reference Model for Heat Generation in the Lithosphere

    Science.gov (United States)

    Wipperfurth, S. A.; Sramek, O.; Roskovec, B.; Mantovani, F.; McDonough, W. F.

    2017-12-01

    Models integrating geophysics and geochemistry allow for characterization of the Earth's heat budget and geochemical evolution. Global lithospheric geophysical models are now constrained by surface and body wave data and are classified into several unique tectonic types. Global lithospheric geochemical models have evolved from petrological characterization of layers to a combination of petrologic and seismic constraints. Because of these advances regarding our knowledge of the lithosphere, it is necessary to create an updated chemical and physical reference model. We are developing a global lithospheric reference model based on LITHO1.0 (segmented into 1°lon x 1°lat x 9-layers) and seismological-geochemical relationships. Uncertainty assignments and correlations are assessed for its physical attributes, including layer thickness, Vp and Vs, and density. This approach yields uncertainties for the masses of the crust and lithospheric mantle. Heat producing element abundances (HPE: U, Th, and K) are ascribed to each volume element. These chemical attributes are based upon the composition of subducting sediment (sediment layers), composition of surface rocks (upper crust), a combination of petrologic and seismic correlations (middle and lower crust), and a compilation of xenolith data (lithospheric mantle). The HPE abundances are correlated within each voxel, but not vertically between layers. Efforts to provide correlation of abundances horizontally between each voxel are discussed. These models are used further to critically evaluate the bulk lithosphere heat production in the continents and the oceans. Cross-checks between our model and results from: 1) heat flux (Artemieva, 2006; Davies, 2013; Cammarano and Guerri, 2017), 2) gravity (Reguzzoni and Sampietro, 2015), and 3) geochemical and petrological models (Rudnick and Gao, 2014; Hacker et al. 2015) are performed.

  2. Heat Generation Effects on U-Mo/Al through ABAQUS FEM Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Taewon; Jeong, Gwan Yoon; Lee, Cheol Min; Sohn Dongseong [Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of)

    2014-05-15

    U-Mo/Al dispersion fuels have been considered a most promising candidate for a replacement of Highly Enriched Uranium (HEU) fuel in many research reactors. Coulson developed a FEM model which show the fuel meat realistically and compared the thermal conductivity results of two and three dimensional model. Williams also developed a FEM model which are different from the former in that it use regularly meshed unit cells. He showed a heat generation effects through FEM simulation and the effective thermal conductivity of the fuel with heat generated in the fuel particles is a little lower than that of the fuel with no heat generated. In the current work, the heat generation effects are analyzed and discussed in a wider range of volume fraction with more realistic models by using ABAQUS finite element package. The FEM model is used to determine the effective thermal conductivity of U-Mo/Al and to simulate the heat generation effects in the study. This model reflected the microscopic morphology of the fuel very well by making random distribution particles although the particle shape is considered as sphere. All simulation results show the heat generation effects although the effects are small when the volume fraction of fuels are high. When the particles are surrounded with interaction layers, the heat transfer from the particle to matrix is disturbed by interaction layers due to the low thermal conductivity of interaction layers. However this effects decreases when the sum of the volume fraction of fuels and interaction layers exceeds 40-50 vol% because a great portion of the heat must pass through fuels and interaction layers although the heat is applied on the surface. Therefore particle size and initial particle volume fractions will be the important factors for the heat generation effects when interaction layers grow during irradiations.

  3. Steam generator concept of a small HTR for reheating and for removal of the residual heat

    Energy Technology Data Exchange (ETDEWEB)

    Singh, J; Barnert, H; Hohn, H; Mondry, M [Institut fuer Reaktorenentwicklung, Kernforschungsanlage Juelich GmbH, Juelich (Germany)

    1988-07-01

    The steam generator of a small HTR is arranged above the core in an in line design of the primary loop, thereby helium flows upwards. Water flows downwards in the steam generator to realize cross flow. To achieve stable evaporation conditions during part load operation it is desired to realize upward evaporation in the steam generator. Moreover if the steam generator is also used as a heat sink for removal of residual heat, this desire of upwards evaporation becomes more imperative. It is possible to realize the design of steam generator with upwards evaporation by arranging a hot gas duct in its central region, so that hot helium can flow upwards through it. Therefore helium enters the steam generator from the top and flows downwards and water upwards. In the presented design, a heat exchanger is arranged in the central region of the steam generator instead of a hot gas duct. Hot helium of 750 deg. C flows upwards in this heat exchanger and thereby cools down to the temperature of about 700 deg. C before it enters the bundle of the steam generator at the top. Through an intermediate loop this heat is transferred outside the primary loop, where in an extra heat exchanger live steam is reheated to improve the thermal efficiency of the plant. This intermediate loop works on the basis of forced convection and transfer about 25 MW for reheating. During the shutdown operation of the reactor, this heat exchanger in the central region of the steam generator serves as a heat sink for removal of the residual heat through natural convection in the primary loop. At the same time it is further possible, that intermediate loop also works on the basis of natural convection, because during shutdown operation only a very small amount of heat has to be removed and moreover the outside heat exchanger can be arranged much higher above the central heat exchanger to get favourable conditions for the natural convection. Some of the highlights of the central heat exchanger are: coaxial

  4. Radiation monitors of new generation - New methodology of detection of nuclear and radioactive materials

    International Nuclear Information System (INIS)

    Kagan, L.; Stavrov, A.

    2001-01-01

    (customs) officers, who as a rule are not experts in the field of radiation control and radiation protection. Therefore, an urgent task for the present is to develop simple, reliable and inexpensive instruments that would allow several of the mentioned tasks to be simultaneously fulfilled. For the last years instruments of a new generation such as the PM1703 and the PM1710 that combine functions of different class devices have been developed. The main distinguishing and favorable features and advantages of these devices are as follows: These devices having small weight and dimensions permit not only effective detection of radioactive sources, but also their location; Special algorithm gives an opportunity to find sources not only with decreasing background as compared to the natural background value due to its shielding (e.g. by scrap), but also with increasing background due to other source (location of one source in the field of the other one); The devices have a non-volatile memory for the history accumulation and storage: time and date of the device switch on/off, source detection cases, etc. The history of operation may be transmitted to the PC for its further storage and processing; The devices have two LCD display modes: in the count rate units (the sources being detected and located in this mode) and in the dose rate units, which allows the evaluation of a danger of the detected and located source to a person. The above-mentioned features of the described devices give an opportunity to develop a new methodology of detection of sources: Owing to small weight and dimensions and a low power consumption the user may hold these devices in a pocket (on a belt) during the entire working shift without switching them off; The user may fulfil his usual professional duties not related to the radiation control and even may not be concerned about the device and its operation - the device functions in the automatic mode and all the information about its operation is accumulated

  5. Long-lived radioactive waste and nuclear plant decommissioning a legacy to future generations

    International Nuclear Information System (INIS)

    McAulay, I.R.

    1996-01-01

    Radioactive waste is an inevitable by-product of all uses of radioactive substances. This is the case of natural radioactivity as well as for artificially produced radioactive isotopes, and it is easy to overlook the significance of the waste problem in the case of technologically enhanced natural radioactivity. Several options are available for the disposal of radioactive waste and the paper considers these in detail from the point of view of the possible future impact of radiation doses to individuals or populations. Particular consideration is given to the use of deep disposal at stable geological sites as a means of dealing with large amounts of radioactive waste. It should not be forgotten that some of what we term waste today need not necessarily always be so. Indeed, there is a good case to make for the recycling of low activity materials rather than the uneconomic expedient of burying them. The paper will consider the possible recycling of valuable materials following suitable reprocessing and dilution and mention the dose implications of examples of such re-utilisation of radioactive materials

  6. CAN WE CONSIDER WASTES GENERATED DURING RADIOIMMUNOASSAYS AS A RADIOACTIVE WASTE?

    Directory of Open Access Journals (Sweden)

    V. V. Shapilov

    2010-01-01

    Full Text Available The work presents issues of the radiation protection provision for the management of radioactive waste produced by the radioimmunological analysis with the use of 125I marker, calculated and experimental data on radioactive waste specific activities are analyzed.

  7. Determination of the radioactive aerosols transport coefficients generated in open pit uranium mining areas

    International Nuclear Information System (INIS)

    Azevedo Py Junior, D. de.

    1978-01-01

    The classical atmospheric transport model is applied to uranium mining operations. Among the transport parameters there is one concerned with radioactive decay, but it does not include the radioactive decay series which is the specific case for uranium. Therefore, an extension of the transport theory is developed and tested, giving results greater than the ones obtained with the classical model, as expected. (author)

  8. Long-lived radioactive waste and nuclear plant decommissioning a legacy to future generations

    Energy Technology Data Exchange (ETDEWEB)

    McAulay, I R [Trinity Coll., Dublin (Ireland). Physical Lab.

    1996-10-01

    Radioactive waste is an inevitable by-product of all uses of radioactive substances. This is the case of natural radioactivity as well as for artificially produced radioactive isotopes, and it is easy to overlook the significance of the waste problem in the case of technologically enhanced natural radioactivity. Several options are available for the disposal of radioactive waste and the paper considers these in detail from the point of view of the possible future impact of radiation doses to individuals or populations. Particular consideration is given to the use of deep disposal at stable geological sites as a means of dealing with large amounts of radioactive waste. It should not be forgotten that some of what we term waste today need not necessarily always be so. Indeed, there is a good case to make for the recycling of low activity materials rather than the uneconomic expedient of burying them. The paper will consider the possible recycling of valuable materials following suitable reprocessing and dilution and mention the dose implications of examples of such re-utilisation of radioactive materials.

  9. Experiments and simulations on heat exchangers in thermoelectric generator for automotive application

    International Nuclear Information System (INIS)

    Liu, X.; Deng, Y.D.; Zhang, K.; Xu, M.; Xu, Y.; Su, C.Q.

    2014-01-01

    In this work, an energy-harvesting system which extracts heat from an automotive exhaust pipe and turns the heat into electricity by using thermoelectric power generators (TEGs) was built. Experiments show that the temperature difference in automotive system is not constant, especially the heat exchanger, which cannot provide the thermoelectric modules (TMs) large amount of heat. The thermal performance of different heat exchangers in exhaust-based TEGs is studied in this work, and the thermal characteristics of heat exchangers with different internal structures and thickness are discussed, to obtain higher interface temperature and thermal uniformity. Following computational fluid dynamics simulations, infrared experiments and output power testing system are carried out on a high-performance production engine with a dynamometer. Results show that a plate-shaped heat exchanger with chaos-shaped internal structure and thickness of 5 mm achieves a relatively ideal thermal performance, which is practically useful to enhance the thermal performance of the TEG, and larger total output power can be thus obtained. - Graphical abstract: The thermal and electrical characteristics of different heat exchangers of automotive exhaust-based thermoelectric generator are discussed, to obtain higher interface temperature and thermal uniformity. - Highlights: • Different internal structures and thickness of heat exchangers were proposed. • Power output testing system of the two heat exchangers was characterized. • Chaos-shaped heat exchanger (5 mm thickness) shows better performance

  10. Transient thermal stresses in circular cylinder under intermittently sudden heat generation

    International Nuclear Information System (INIS)

    Sugano, Y.; Saito, K.; Takeuti, Y.

    1975-01-01

    The thermal stresses associated with the transient temperature distribution arising in a circular cylinder under intermittently changing sudden heat generation over a finite band and with heat loss to a surrounding medium on the remainder of the cylinder surface are exactly analysed. For the first time the temperature field in a circular cylinder under sudden heat generation over a finite band of the cylinder surface is determined by combined use of Fourier cosine, Laplace transforms in axial position and time, respectively. Secondly it is assumed that the temperature fields in a circular cylinder subjected to heat generation Qsub(i) (i=0, 1, 2, ...) independently over a finite band are given by T 0 (r,z,t), T 1 (r,z,t), T 2 (r,z,t),... respectively. Tsub(i)(r,z,t) indicates the temperature field before the i-th heat generation Qsub(i). The thermal stresses associated with the temperature field described above are analysed by using the Hoyle stress functions. Numerical calculations are carried out for the extensive case of the ratio of the heat-generating length to the diameter of cylinder. It is found that the time in which the maximum stresses occur on the cylinder surface does not depend on the heat-generating length-to-diameter ratio

  11. Improvement of the decay heat removal characteristics of the generation IV gas-cooled fast reactor

    International Nuclear Information System (INIS)

    Epiney, A. S.

    2010-09-01

    The majority of NPPs worldwide are currently light water reactors, using ordinary water as both coolant and moderator. (...) For the longer-term future, viz. beyond the year 2030, Research and Development is currently ongoing on Generation IV NPPs, aimed at achieving closure of the nuclear fuel cycle, and hence both drastically improved utilization of fuel resources and minimization of long-lived radioactive wastes. Since the very beginning of the international cooperation on Generation IV, viz. the year 2000, the main research interest in Europe as regards the advanced fast-spectrum systems needed for achieving complete fuel cycle closure, has been for the Sodium-cooled Fast Reactor (SFR). However, the Gas-cooled Fast Reactor (GFR) is currently considered as the main back-up solution. Like the SFR, the GFR is an efficient breeder, also able to work as iso-breeder using simply natural uranium as feed and producing waste which is predominantly in the form of fission products. The main drawback of the GFR is the difficulty to evacuate decay heat following a loss-of-coolant accident (LOCA) due to the low thermal inertia of the core, as well as to the low coolant density. The present doctoral research focuses on the improvement of decay heat removal (DHR) for the Generation-IV GFR. The reference GFR system design considered in the thesis is the 2006 CEA concept, with a power of 2400 MWth. The CEA 2006 DHR strategy foresees, in all accidental cases (independent of the system pressure), that the reactor is shut down. For high pressure events, dedicated DHR loops with blowers and heat exchangers are designed to operate when the power conversion system cannot be used to provide acceptable core temperatures under natural convection conditions. For depressurized events, the strategy relies on a dedicated small containment (called the guard containment) providing an intermediate back-up pressure. The DHR blowers, designed to work under these pressure conditions, need to be

  12. Steady-state heat transfer in an inverted U-tube steam generator

    International Nuclear Information System (INIS)

    Boucher, T.J.

    1987-01-01

    Experimental results are presented involving U-tube steam generator tube bundle local heat transfer and fluid conditions during stead-state, full-power operations performed at high temperatures and pressures with conditions typical of a pressurized water reactor (15.0 MPa primary pressure, 600 K steam generator inlet plenum fluid temperatures, 6.2 MPa secondary pressure). The Semiscale (MOD-2C facility represents the state-of-the-art in measurement of tube local heat transfer data and average tube bundle secondary fluid density at several elevations, which allows an estimate of the axial heat transfer and void distributions during steady-state and transient operations. The method of heat transfer data reduction is presented and the heat flux, secondary convective heat transfer coefficient, and void fraction distributions are quantified for steady-state, full-power operations

  13. Numerical study of entropy generation and melting heat transfer on ...

    Indian Academy of Sciences (India)

    Z Iqbal

    2018-04-16

    Apr 16, 2018 ... Z IQBAL, ZAFFAR MEHMOOD and BILAL AHMAD. ∗. Department of Mathematics ... of entropy generation is appraised on thermal and fluid velocities. Physical features of ... field of science and technology. In these fluids ...

  14. Analysis and Modeling of Heat Generation in Overcharged Li-Ion Battery with Passive Cooling

    DEFF Research Database (Denmark)

    Coman, Paul Tiberiu; Veje, Christian

    2013-01-01

    This paper presents a dynamic model for simulating the heat generation in Lithium batteries and an investigation of the heat transfer as well as the capacity of Phase Change Materials (PCM’s) to store energy inside a battery cell module when the battery is overcharged. The study is performed...... by coupling a one-dimensional model of the electrochemical processes with a two-dimensional model for the heat transfer in a cross section of a battery pack. The heat generation and subsequent temperature rise is analyzed for different charging currents for the two cases where the cell is air......-cooled and passively cooled using a PCM, respectively. As expected, the results show that for high currents, the heat generation and implicitly the temperature increases. However, using a PCM the temperature increase is found to be limited allowing the battery to be overcharged to a certain degree. It is found...

  15. Thermoelectric as recovery and harvesting of waste heat from portable generator

    Science.gov (United States)

    Mustafa, S. N.; Kamarrudin, N. S.; Hashim, M. S. M.; Bakar, S. A.; Razlan, Z. M.; Harun, A.; Ibrahim, I.; Faizi, M. K.; Saad, M. A. M.; Zunaidi, I.; Wan, W. K.; Desa, H.

    2017-10-01

    Generation of waste heat was ineluctable especially during energy producing process. Waste heat falls into low temperature grade make it complicated to utilize. Thermoelectric generator (TEG) offers opportunity to harvest any temperature grade heat into useful electricity. This project is covered about recovery and utilizing waste heat from portable electric generator by using a TEG which placed at exhaust surface. Temperature difference at both surfaces of TEG was enhanced with supplying cold air from a wind blower. It is found that, even at low air speed, the TEG was successfully produced electricity with aid from DC-DC booster. Results shows possibility to harvest low temperature grade heat and still exist areas for continual improvement.

  16. Dry out of a fluidized particle bed with internal heat generation

    International Nuclear Information System (INIS)

    Keowen, R.S.; Catton, I.

    1975-03-01

    An apparatus was designed to adequately simulate the characteristics of a particle bed formed by nuclear reactor fuel after the reactor has been operable for some length of time at high power. This was accomplished by using a 10 KW, 453 Kc induction heater, coupled through a multi-turn work coil to particle beds of cast steel shot and lead shot in water. The temperature response and dryout condition was determined for various bed levels, particle diameters, and heat fluxes. Analysis of the data retrieved from the bed was used to generate a family of curves to predict the necessary conditions for dryout to occur within a fluidized particle bed with internal heat generation. The results presented here, with internal heat generation, show that previous results with bottom heating and volume heating are conservative. (U.S.)

  17. Qualification of Alloy 800 for sodium heated steam generators

    International Nuclear Information System (INIS)

    Duke, J.M.; Sessions, C.E.; Ray, W.E.

    1976-01-01

    A reference specification of Alloy 800 for use in LMFBR steam generators is defined considering waterside corrosion, weldability and mechanical properties. Additional mechanical test data are being generated to support ASME Code acceptance. Candidate weld filler metals were assessed for use in subsequent weld process development. Progress on resolving technical concerns related to the role of tertiary creep identified the impact of test conditions and gamma prime strengthening in determining the creep behavior of Alloy 800

  18. Synthesis of gels with basis of titanium tungstates as matrixes of radioactive generators

    International Nuclear Information System (INIS)

    Galico C, L.

    2005-01-01

    The heteropolyanions, compounds formed by the union of molybdates or tungstates polyanions with atoms of metals like zirconium, titanium, cerium, thorium, tin, etc., have been used as generator matrixes of 99m Tc or 188 Re. Particularly they have been studied and produced successfully in our laboratory, generators of 99 Mo/ 99 m Tc at basis of gels zirconium molybdates and titanium molybdates. Considering that the molybdenum and tungsten, as well as the technetium and the rhenium, its belong to the same groups of transition metals, it is feasible that gels can be synthesized at basis of titanium tungstates, continuing a methodology similar to that of the gels titanium molybdates or zirconium molybdates, to produce generators 188 W/ 188 Re. The 188 Re possess nuclear characteristics that make it attractive for therapeutic applications, since, it emits β - particles of a great energy (2.12 MeV); joined to the possibility of being able to unite to different ligands (bifunctional agents) and biomolecules (antibodies or fragments of proteins), as it makes the 99m Tc, useful in radioimmunotherapy. Commercially the 188 Re generators use a chromatographic column loaded with alumina where the 188 Re, it is adsorbed and eluted the 188 ReO 4 - by means of a saline solution The alumina adsorbs around 0.2% of the 188 Re, situation that forces to use 188 Re of a high specific activity. The use of the gels technology, allows to work with medium or low specific activities of 188 Re, opening the possibility of their production in countries whose nuclear capacity is medium or low. In particular, the synthesized gels with basis of titanium offer the possibility of being synthesized with non active material, for later on to be irradiated and directly produce the generator, since, the titanium 51 Ti, unique radioisotope produced by the titanium, has a half life of 5.79 min. This synthesis method avoids the manipulation of radioactive material during the synthesis of the gels, process

  19. Influence of heat pipe operating temperature on exhaust heat thermoelectric generation

    OpenAIRE

    Brito, F. P.; Martins, Jorge; Gonçalves, L. M.; Antunes, Nuno; Sousa, Diogo

    2013-01-01

    Increasingly stringent targets on energy efficiency and emissions, as well as growing vehicle electrification are making attractive the electric recovery of the energy normally wasted through the tailpipe of Internal Combustion Engines. Recent developments in thermoelectrics (TE) may soon make them a viable solution for such applications. This team has been exploring the potential of using TE modules in combination with variable conductance heat pipes for transferring the exhaust heat to ...

  20. Radioactive waste management

    International Nuclear Information System (INIS)

    1984-07-01

    The purpose of this document is to set out the Government's current strategy for the long term in the management of radioactive wastes. It takes account of the latest developments, and will be subject to review in the light of future developments and studies. The subject is discussed under the headings: what are radioactive wastes; who is responsible; what monitoring takes place; disposal as the objective; low-level wastes; intermediate-level wastes; discharges from Sellafield; heat generating wastes; how will waste management systems and procedures be assessed; how much more waste is there going to be in future; conclusion. (U.K.)

  1. 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)

  2. Investigation of Counter-Flow in a Heat Pipe-Thermoelectric Generator (HPTEG)

    Science.gov (United States)

    Remeli, Muhammad Fairuz; Singh, Baljit; Affandi, Nor Dalila Nor; Ding, Lai Chet; Date, Abhijit; Akbarzadeh, Aliakbar

    2017-05-01

    This study explores a method of generating electricity while recovering waste heat through the integration of heat pipes and thermoelectric generators (i.e. HPTEG system). The simultaneous waste heat recovery and power generation processes are achieved without the use of any moving parts. The HPTEG system consists of bismuth telluride thermoelectric generators (TEG), which are sandwiched between two finned pipes to achieve a temperature gradient across the TEG for electricity generation. A counter-flow heat exchanger was built using two separate air ducts. The air ducts were thermally coupled using the HPTEG modules. The evaporator section of the heat pipe absorbed the waste heat in a hot air duct. The heat was then transferred across the TEG surfaces. The condenser section of the HPTEG collected the excess heat from the TEG cold side before releasing it to the cold air duct. A 2-kW electrical heater was installed in the hot air duct to simulate the exhaust gas. An air blower was installed at the inlet of each duct to direct the flow of air into the ducts. A theoretical model was developed for predicting the performance of the HPTEG system using the effectiveness-number of transfer units method. The developed model was able to predict the thermal and electrical output of the HPTEG, along with the rate of heat transfer. The results showed that by increasing the cold air velocity, the effectiveness of the heat exchanger was able to be increased from approximately 52% to 58%. As a consequence of the improved heat transfer, maximum power output of 4.3 W was obtained.

  3. Main results of assessing integrity of RNPP-3 steam generator heat exchange tubes in accident management

    International Nuclear Information System (INIS)

    Shugajlo, Al-j P.; Mustafin, M.A.; Shugajlo, Al-r P.; Ryzhov, D.I.; Zhabin, O.I.

    2017-01-01

    Tubes integrity evaluation under accident conditions considering drain of SG and current technical state of steam exchange tubes is an important question regarding SG long-term operation and improvement of accident management strategy.The main investigation results prepared for heat exchange surface of RNPP-3 steam generator are presented in this research aimed at assessing integrity of heat exchange tubes under accident conditions, which lead to full or partial drain of heat exchange surface, in particular during station blackout.

  4. A thermoelectric power generating heat exchanger: Part I – Experimental realization

    DEFF Research Database (Denmark)

    Bjørk, Rasmus; Sarhadi, Ali; Pryds, Nini

    2016-01-01

    An experimental realization of a heat exchanger with commercial thermoelectric generators (TEGs) is presented. The power producing capabilities as a function of flow rate and temperature span are characterized for two different commercial heat transfer fluids and for three different thermal...

  5. Development of Thermoelectric Power Generators for high temperature Waste Heat Recovery

    DEFF Research Database (Denmark)

    Van Nong, Ngo; Pryds, Nini

    By converting heat directly into electricity, thermoclectric generators (TEGs) provide a very promising solution for emerging energy saving and environmental issues. These devices could be incorporated in a variety of applications, in particular those making use of waste heat recovery. To expand...

  6. Determination of thermal characteristics of combustion products of fire-tube heat generator with flow turbulator

    Directory of Open Access Journals (Sweden)

    Lukjanov Alexander V.

    2014-12-01

    Full Text Available Boiler construction is one of the major industries of any state. The aim is to determine the effect of the turbulator on the intensity of heat transfer in the convective part of the fire-tube heat generator of domestic production. The improvement of convective heating surfaces is one of the ways to increase the energy efficiency of the fire-tube heat generator. Since model of the process of heat transfer of gas flow in the convective tubes is multifactorial and does not have clear analytical solution at present, the study of process above is carried out using the experimental method. The results of applying the flow turbulator as a broken tape in the fire-tube heat generator of KV-GM type are presented. On their basis it can be concluded about increasing of heat transfer in convective part of the unit. The use of efficient, reliable, easy to manufacture, relatively inexpensive turbulator in domestic fire-tube heat generators will allow to increase their energy conversion efficiency and reduce fuel consumption, which will have a positive economic effect.

  7. Numerical investigation of passive heat removal system via steam generator in VVER 1200

    International Nuclear Information System (INIS)

    Dinh Anh Tuan; Duong Thanh Tung; Tran Chi Thanh; Nguyen Van Thai

    2015-01-01

    Passive heat removal system (PHRS) via Steam Generator is an important part in VVER design. In case of Design Basic Accidents such as blackout, failure of feed water supply to steam generator or coolant leakage with failure of emergency core cooling at high pressure. PHRS is designed to remove the residual heat from reactor core through steam generator to heat exchanger which is placed outside reactor vessel. In order to evaluate the passive system, a numerical investigation using a CFD code is performed. However, PHRS has complex geometry for using CFD simulation. Thus, RELAP5 is applied to provide the wall heat flux of tube in the heat exchanger tank. The natural convection in the heat exchanger tank is investigated in this report. Numerical results show temperature and velocity distribution in the heat exchanger tank are calculated with different wall heat flux corresponding to various transient conditions. The calculated results contribute to the capacity analysis of passive heat removal system and giving valuable information for safe operation of VVER 1200. (author)

  8. Measuring the linear heat generation rate of a nuclear reactor fuel pin

    International Nuclear Information System (INIS)

    Smith, R.D.

    1981-01-01

    A miniature gamma thermometer is described which is capable of travelling through bores distributed in an array through a nuclear reactor core and measure the linear heat generation rate of the fuel pins. (U.K.)

  9. 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

  10. Heat generation and temperature-rise in ordinary concrete due to capture of thermal neutrons

    International Nuclear Information System (INIS)

    Abdo, E.A.; Amin, E.

    1997-01-01

    The aim of this work is the evaluation of the heat generation and temperature-rise in local ordinary concrete as a biological shield due to capture of total thermal and reactor thermal neutrons. The total thermal neutron fluxes were measured and calculated. The channel number 2 of the ETRR-1 reactor was used in the measurements as a neutron source. Computer code ANISN (VAX version) and neutron multigroup cross-section library EURLiB-4 was used in the calculations. The heat generation and temperature-rise in local ordinary concrete were evaluated and calculated. The results were displayed in curves to show the distribution of thermal neutron fluxes and heat generation as well as temperature-rise with the shield thickness. The results showed that, the heat generation as well as the temperature-rise have their maximum values in the first layers of the shield thickness. 4 figs., 12 refs

  11. Thermal effect of a thermoelectric generator on parallel microchannel heat sink

    DEFF Research Database (Denmark)

    Kolaei, Alireza Rezania; Rosendahl, Lasse

    2012-01-01

    Thermoelectric generators (TEG) convert heat energy to electrical power by means of semiconductor charge carriers serving as working fluid. In this work, a TEG is applied to a parallel microchannel heat sink. The effect of the inlet plenum arrangement on the laminar flow distribution...... in the channels is considered at a wide range of the pressure drop along the heat sink. The particular focus of this study is geometrical effect of the TEG on the heat transfer characteristics in the micro-heat sink. The hydraulic diameter of the microchannels is 270 μm, and three heat fluxes are applied...... on the hot surface of the TEG. By considering the maximum temperature limitation for Bi_2 Te_3 material and using the microchannel heat sink for cooling down the TEG system, an optimum pumping power is achieved. The results are in a good agreement with the previous experimental and theoretical studies....

  12. Water, vapour and heat transport in concrete cells for storing radioactive waste

    Science.gov (United States)

    Carme Chaparro, M.; W. Saaltink, Maarten

    2016-08-01

    Water is collected from a drain situated at the centre of a concrete cell that stores radioactive waste at 'El Cabril', which is the low and intermediate level radioactive waste disposal facility of Spain. This indicates flow of water within the cell. 2D numerical models have been made in order to reproduce and understand the processes that take place inside the cell. Temperature and relative humidity measured by sensors in the cells and thermo-hydraulic parameters from laboratory test have been used. Results show that this phenomenon is caused by capillary rise from the phreatic level, evaporation and condensation within the cell produced by temperature gradients caused by seasonal temperature fluctuations outside. At the centre of the cell, flow of gas and convection also play a role. Three remedial actions have been studied that may avoid the leakage of water from the drain.

  13. Increased Heat Generation in Postcardiac Arrest Patients During Targeted Temperature Management Is Associated With Better Outcomes.

    Science.gov (United States)

    Uber, Amy J; Perman, Sarah M; Cocchi, Michael N; Patel, Parth V; Ganley, Sarah E; Portmann, Jocelyn M; Donnino, Michael W; Grossestreuer, Anne V

    2018-04-03

    Assess if amount of heat generated by postcardiac arrest patients to reach target temperature (Ttarget) during targeted temperature management is associated with outcomes by serving as a proxy for thermoregulatory ability, and whether it modifies the relationship between time to Ttarget and outcomes. Retrospective cohort study. Urban tertiary-care hospital. Successfully resuscitated targeted temperature management-treated adult postarrest patients between 2008 and 2015 with serial temperature data and Ttarget less than or equal to 34°C. None. Time to Ttarget was defined as time from targeted temperature management initiation to first recorded patient temperature less than or equal to 34°C. Patient heat generation ("heat units") was calculated as inverse of average water temperature × hours between initiation and Ttarget × 100. Primary outcome was neurologic status measured by Cerebral Performance Category score; secondary outcome was survival, both at hospital discharge. Univariate analyses were performed using Wilcoxon rank-sum tests; multivariate analyses used logistic regression. Of 203 patients included, those with Cerebral Performance Category score 3-5 generated less heat before reaching Ttarget (median, 8.1 heat units [interquartile range, 3.6-21.6 heat units] vs median, 20.0 heat units [interquartile range, 9.0-33.5 heat units]; p = 0.001) and reached Ttarget quicker (median, 2.3 hr [interquartile range, 1.5-4.0 hr] vs median, 3.6 hr [interquartile range, 2.0-5.0 hr]; p = 0.01) than patients with Cerebral Performance Category score 1-2. Nonsurvivors generated less heat than survivors (median, 8.1 heat units [interquartile range, 3.6-20.8 heat units] vs median, 19.0 heat units [interquartile range, 6.5-33.5 heat units]; p = 0.001) and reached Ttarget quicker (median, 2.2 hr [interquartile range, 1.5-3.8 hr] vs median, 3.6 hr [interquartile range, 2.0-5.0 hr]; p = 0.01). Controlling for average water temperature between initiation and Ttarget, the

  14. CFD analysis of fin tube heat exchanger with a pair of delta winglet vortex generators

    International Nuclear Information System (INIS)

    Hwang, Seong Won; Kim, Dong Hwan; Min, June Kee; Jeong, Ji Hwan

    2012-01-01

    Among tubular heat exchangers, fin tube types are the most widely used in refrigeration and air-conditioning equipment. Efforts to enhance the performance of these heat exchangers included variations in the fin shape from a plain fin to a slit and louver type. In the context of heat transfer augmentation, the performance of vortex generators has also been investigated. Delta winglet vortex generators have recently attracted research interest, partly due to experimental data showing that their addition to fin-tube heat exchangers considerably reduces pressure loss at heat transfer capacity of nearly the same level. The efficiency of the delta winglet vortex generators widely varies depending on their size and shape, as well as the locations where they are implemented. In this paper, the flow field around delta winglet vortex generators in a common flow up arrangement was analyzed in terms of flow characteristics and heat transfer using computational fluid dynamics methods. Flow mixing due to vortices and delayed separation due to acceleration influence the overall fin performance. The fin with delta winglet vortex generators exhibited a pressure loss lower than that of a plain fin, and the heat transfer performance was enhanced at high air velocity or Reynolds number

  15. Isothermal calorimeter for measurements of time-dependent heat generation rate in individual supercapacitor electrodes

    Science.gov (United States)

    Munteshari, Obaidallah; Lau, Jonathan; Krishnan, Atindra; Dunn, Bruce; Pilon, Laurent

    2018-01-01

    Heat generation in electric double layer capacitors (EDLCs) may lead to temperature rise and reduce their lifetime and performance. This study aims to measure the time-dependent heat generation rate in individual carbon electrode of EDLCs under various charging conditions. First, the design, fabrication, and validation of an isothermal calorimeter are presented. The calorimeter consisted of two thermoelectric heat flux sensors connected to a data acquisition system, two identical and cold plates fed with a circulating coolant, and an electrochemical test section connected to a potentiostat/galvanostat system. The EDLC cells consisted of two identical activated carbon electrodes and a separator immersed in an electrolyte. Measurements were performed on three cells with different electrolytes under galvanostatic cycling for different current density and polarity. The measured time-averaged irreversible heat generation rate was in excellent agreement with predictions for Joule heating. The reversible heat generation rate in the positive electrode was exothermic during charging and endothermic during discharging. By contrast, the negative electrode featured both exothermic and endothermic heat generation during both charging and discharging. The results of this study can be used to validate existing thermal models, to develop thermal management strategies, and to gain insight into physicochemical phenomena taking place during operation.

  16. CFD analysis of fin tube heat exchanger with a pair of delta winglet vortex generators

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Seong Won; Kim, Dong Hwan; Min, June Kee; Jeong, Ji Hwan [Pusan National Univ., Busan (Korea, Republic of)

    2012-09-15

    Among tubular heat exchangers, fin tube types are the most widely used in refrigeration and air-conditioning equipment. Efforts to enhance the performance of these heat exchangers included variations in the fin shape from a plain fin to a slit and louver type. In the context of heat transfer augmentation, the performance of vortex generators has also been investigated. Delta winglet vortex generators have recently attracted research interest, partly due to experimental data showing that their addition to fin-tube heat exchangers considerably reduces pressure loss at heat transfer capacity of nearly the same level. The efficiency of the delta winglet vortex generators widely varies depending on their size and shape, as well as the locations where they are implemented. In this paper, the flow field around delta winglet vortex generators in a common flow up arrangement was analyzed in terms of flow characteristics and heat transfer using computational fluid dynamics methods. Flow mixing due to vortices and delayed separation due to acceleration influence the overall fin performance. The fin with delta winglet vortex generators exhibited a pressure loss lower than that of a plain fin, and the heat transfer performance was enhanced at high air velocity or Reynolds number.

  17. Dryout in sodium-heated helically-coiled steam generator tubes

    International Nuclear Information System (INIS)

    Tomita, Y.; Kosugi, T.; Kubota, J.; Nakajima, K.; Tsuchiya, T.

    1984-01-01

    Experimental research on the dryout phenomenon in sodium heated, helically coiled steam generator tubes was carried out. The fluctuation of the tube wall temperature caused by dryout was measured with thermocouples installed in the center of the tube wall. Empirical correlations of dryout quality were developed as functions of critical heat flux, water mass velocity and saturation pressure. These correlations confirmed that the design criterion of the MONJU steam generator was reasonable. (author)

  18. Heat exchanger tubing materials for CANDU nuclear generating stations

    International Nuclear Information System (INIS)

    Taylor, G.F.

    1977-07-01

    The performance of steam generator tubing (nickel-chromium-iron alloy in NPD and nickel-copper alloy in Douglas Point and Pickering generating stations) has been outstanding and no corrosion-induced failures have occurred. The primary coolant will be allowed to boil in the 600 MW (electrical) CANDU-PHW reactors. An iron-nickel-chromium alloy has been selected for the steam generator tubing because it will result in lower radiation fields than the alloys used before. It is also more resistant than nickel-chromium-iron alloy to stress corrosion cracking in the high purity water of the primary circuit, an unlikely but conceivable hazard associated with higher operating temperatures. Austenitic alloy and ferritic-austenitic stainless steel tubing have been selected for the moderator coolers in CANDU reactors being designed and under construction. These materials will reduce the radiation fields around the moderator circuit while retaining the good resistance to corrosion in service water that has characterized the copper-nickel alloys now in use. Brass and bronze tubes in feedwater heaters and condensers have given satisfactory service but do, however, complicate corrosion control in the steam cycle and, to reduce the transport of corrosion products from the feedtrain to the steam generator, stainless steel is preferred for feedwater heaters and stainlss steel or titanium for condensers. (author)

  19. Potential for increased wind-generated electricity utilization using heat pumps in urban areas

    International Nuclear Information System (INIS)

    Waite, Michael; Modi, Vijay

    2014-01-01

    Highlights: • Large-scale wind power and increased electric heat pumps were evaluated. • A deterministic model of wind power and electricity demand was developed. • Sub-models for space heating and domestic hot water demand were developed. • Increased use of heat pumps can improve the viability of large-scale wind power. • Larger wind power capacity can meet a target utilization rate with more heat pumps. - Abstract: The U.S. has substantial wind power potential, but given wind’s intermittent availability and misalignment with electricity demand profiles, large-scale deployment of wind turbines could result in high electricity costs due to energy storage requirements or low utilization rates. While fuel switching and heat pumps have been proposed as greenhouse gas (GHG) emissions and energy reduction strategies at the building scale, this paper shows that heat pump adoption could have additional system-wide benefits by increasing the utilization of wind-generated electricity. A model was developed to evaluate the effects of coupling large-scale wind power installations in New York State with increased use of electric heat pumps to meet a portion of space heating and domestic hot water (DHW) demands in New York City. The analysis showed significant increases in wind-generated electricity utilization with increased use of heat pumps, allowing for higher installed capacity of wind power. One scenario indicates that 78.5% annual wind-generated electricity utilization can be achieved with 3 GW of installed wind power capacity generated electricity equal to 20% of existing NYC annual electricity demand; if 20% of space heating and DHW demands are provided by heat pumps, the 78.5% utilization rate can be achieved with an increase of total wind power capacity to 5 GW. Therefore, this integrated supply–demand approach could provide additional system-wide emissions reductions

  20. IAEA Technical Meeting on Innovative Heat Exchanger and Steam Generator Designs for Fast Reactors. Working Material

    International Nuclear Information System (INIS)

    2011-01-01

    The IAEA, within the framework of its Nuclear Energy Department’s Technical Working Group on Fast Reactors (TWG-FR), assists Member States activities in fast reactors technology development areas by providing an umbrella for information exchange [topical Technical Meetings (TMs), Workshops and large Conferences] and collaborative R&D [Coordinated Research Projects (CRPs)]. The Technical meeting on “Innovative Heat Exchanger and Steam Generator Designs for Fast Reactors” was held from 21 – 22 December 2011 in Vienna, addressing Member States’ expressed needs of information exchange in the field of advanced fast reactor design features, with particular attention to innovative heat exchangers and steam generators. The Objective of the TM is to provide a global forum for in-depth information exchange and discussion on the most advanced concepts of heat exchangers and steam generators for fast reactors. More specifically, the objectives are: · Review of the status of advanced fast reactor development activities with special emphasis on design and performance of heat exchangers and steam generators; · Discuss requirements for innovative heat exchangers and steam generators; · Present results of studies and conceptual designs for innovative heat exchangers and steam generators; · Provide recommendations for international collaboration under the IAEA aegis. The meeting agenda of the meeting is in Annex I

  1. Efficient thermo-mechanical generation of electricity from the heat of radioisotopes

    International Nuclear Information System (INIS)

    Cooke-Yarborough, E.H.; Yeats, F.W.

    1975-01-01

    The thermomechanical generator uses a thermomechanical oscillator to convert heat efficiently into a mechanical oscillation which in turn excites a suitable transducer to generate alternating electricity. The thermomechanical oscillator used is based on the Stirling cycle, but avoids the need for rotary motion and for sliding pistons by having a mechanically-resonant, spring-suspended displacer, and by using an oscillating metal diaphragm to provide the mechanical output. The diaphragm drives an alternator consisting of a spring-suspended permanent magnet oscillating between fixed pole pieces which carry the electrical power output windings. Because a thermomechanical generator is much more efficient than a thermo-electric generator at comparable temperatures, it is particularly suitable for use with a radioisotope heat source. The amounts of radioisotope and of shielding required are both greatly reduced. A machine heated by radioisotopes and delivering 10.7W ac at 80Hz began operating in October, 1974. Operating experience with this machine is reported, and these results, together with those obtained with higher-powered machines heated by other means, are used to calculate characteristics and performance of thermo-mechanical radioisotope generators capable of using heat sources such as the waste-management 90 Sr radioisotope sources becoming available from the US nuclear waste management programme. A design to use one of these heat sources in a 52-W underwater generator is described

  2. Fluid induced structural vibrations in steam generators and heat exchangers

    International Nuclear Information System (INIS)

    Catton, I.; Adinolfi, P.; Alquaddoomi, O.

    2003-01-01

    Fluid-elastic instability (FEI) in tube bundle heat exchangers was studied experimentally. The motion of an array of 15 stainless steel vibrating tubes (Φ 25.4mm) in water cross-flow, suspended using stainless steel piano wire has been recorded with a CCD camera. The individual motion and relative motion of the tubes are reported and can be used for computational model validation. The relative displacement of the tubes allows identification of the most potentially damaging patterns of tube bundle vibration. A critical reduced velocity may be determined by specification of an allowable limit on tube motion amplitude. Measurements were made for various tube array configurations, tube natural frequencies and flow conditions. (author)

  3. Utilization of waste heat from electricity generating stations

    International Nuclear Information System (INIS)

    Robertson, R.F.S.

    1977-06-01

    Historically the nuclear power station has been designed solely as an electricity producer. But in Canada today only 15 percent of our energy consumption is as electricity. The non-electrical needs today are supplied almost entirely by natural gas and oil. There is an incentive to see whether a nuclear station could supply energy for some of these non-electrical needs, thus freeing gas and oil for uses for which they may be more valuable and suitable, especially in transportation. A group located at the Whiteshell Nuclear Research Establishment undertook a series of studies to examine this problem. These studies were done in sufficient depth to provide technological and economic answers, and as a result several reports have been published on various topics. In this report, the findings from these studies are drawn together in an assessment of the potential in Canada for using waste heat. (author)

  4. Numerical simulation of magnetohydrodynamic (MHD) flow with internal heat generation

    International Nuclear Information System (INIS)

    Bokade, Vipin; Bhandarkar, U.V.; Bodi, Kowsik

    2016-01-01

    A strong magnetic field is used to confine the plasma in a fusion reactor. This magnetic field also affects the flow of Lead-Lithium (breeder/coolant) in the breeding blanket. So it is important to study MHD flow of Lead-Lithium (Pb-Li). Open-source toolbox, OpenFOAM, is used to study single phase behaviour of Pb-Li. As the induced magnetic field is very small, Ni et al. electric potential algorithm is employed in OpenFOAM and validated with analytical results. This solver can also solve the temperature field with heat source term. Simulations are carried out in 2D straight channel for various values of Hartmann Number ranging from 100 to 5000 and velocity profile, temperature, current density and pressure drop are studied. (author)

  5. Radioactive battery

    International Nuclear Information System (INIS)

    Deaton, R.L.; Silver, G.L.

    1975-01-01

    A radioactive battery is described that is comprised of a container housing an electrolyte, two electrodes immersed in the electrolyte and insoluble radioactive material disposed adjacent one electrode. Insoluble radioactive material of different intensity of radioactivity may be disposed adjacent the second electrode. If hydrobromic acid is used as the electrolyte, Br 2 will be generated by the radioactivity and is reduced at the cathode: Br 2 + 2e = 2 Br - . At the anode Br - is oxidized: 2Br - = Br 2 + 2e. (U.S.)

  6. Hanford Site annual dangerous waste report: Volume 2, Generator dangerous waste report, radioactive mixed waste

    International Nuclear Information System (INIS)

    1994-01-01

    This report contains information on radioactive mixed wastes at the Hanford Site. Information consists of shipment date, physical state, chemical nature, waste description, waste number, waste designation, weight, and waste designation

  7. Factors determining the stainless steel decontamination efficiency for the steam generator heat exchanger tubes at NPPs with the WWERs

    International Nuclear Information System (INIS)

    Kamenskij, A.N.; Balaban-Irmenin, Yu.V.

    1983-01-01

    To raise the efficiency of the redox method and decrease the amount of radioactive wastes, a possibility of improving the decontamination process for NPP heat exchanger tubes made of stainless steel is studied. In the home practice the redox method of equipment decontamination is carried out as a multi-cycle process. In each cycle the surface is treated first with a permanganate alkaline solution ther with an oxalic acid solution, with a condensate washing-at between the treatments. Using samples cut out of the steam generator pipelines of the first and third power units of the Novovoronezh NPP the effect of the oXalic acid concentration, as well as washout time and conditions on the decontamination factor are studied. On the basis of analysis of the obtained data a conclusion is drawn that using oxalic acid of low concentrations and increasing its concentrations from cycle to cycle maximum decontamination factor values can be obtained at a minimum salt content in radioactive wastes

  8. Solution microcalorimeter for measuring heats of solution of radioactive elements and compounds

    International Nuclear Information System (INIS)

    Raschella, D.L.

    1978-12-01

    The microcalorimeter vessel is constructed of tantalum metal, with a nominal volume of 5 cm 3 . Its energy equivalent is 24 J K -1 when containing 5 cm 3 H 2 O. The thermal leakage modulus is 0.010 min -1 . A thermistor is employed as the temperature sensor. The operating sensitivity is about 1 x 10 -5 K (300 μJ). The performance of the calorimetry system was tested using tris(hydroxymethyl)aminomethane (TRIS) and magnesium metal. The results of the TRIS experiments, at a concentration of 1 g dm -3 in 0.1 N HCl at 298 K, yielded a heat of solution of -29.606 +- 0.063 kJ mol -1 . The magnesium experiments, in 1 N HCl at 298 K, gave a heat of solution of -465.965 +- 1.136 kJ mol -1 . The heat of solution of curium-248 metal in 1 N HCl at 298 K was measured. The experiments, which should not be considered definitive, yielded a heat of solution of -606.4 +- 1.8 kJ mol -1 . A single measurement in 6 N HCl gave a heat of solution of -602.3 kJ mol -1 . From these results the heat of formation of Cm 3+ /sub (aq)/ is calculated to be -607.2 +- 2.5 kJ mol -1

  9. An assessment of radioactivity level in 51Cr-contaminated dry solid waste generated from a research facility for verification of clearance levels

    International Nuclear Information System (INIS)

    Nagamatsu, Tomohiro; Yamaoka, Kiyonori; Hanafusa, Tadashi; Ono, Toshiro

    2010-01-01

    Radioactive waste generated from research laboratories and other facilities is regulated by the Law Concerning Prevention from Radiation Hazards due to Radioisotopes etc. (Prevention Law). However, the Prevention Law does not provide the level of clearance or the procedures to follow for compliance monitoring. To assess radioactivity amounts for making decisions about clearance levels, the radioactivity levels in dry solid semi-combustible wastes generated from biomedical research, such as 51 Cr-release assays, were measured and evaluated. Radioactivity of semi-combustible waste was 1.42-6.32% of the initial level. In comparison, records for the past 8 years in the Shikata Laboratory, Department of Radiation Research, Okayama University Advanced Science Research Center, indicated 7% to 90% of the initial radioactivity remained in the waste and was differed widely among researchers. This study determined an accurate radioactivity level in dry solid waste, which could lead to savings in disposal costs. (author)

  10. Parametric numerical investigaion of natural convection in a heat-generating fluid with phase transitions

    Energy Technology Data Exchange (ETDEWEB)

    Aksenova, A.E.; Chudanov, V.V.; Strizhov, V.F.; Vabishchevich, P.N. [Institute of Nuclear Safety Russian Academy Science, Moscow (Russian Federation)

    1995-09-01

    Unsteady natural convection of a heat-generating fluid with phase transitions in the enclosures of a square section with isothermal rigid walls is investigated numerically for a wide range of dimensionless parameters. The quasisteady state solutions of conjugate heat and mass transfer problem are compared with available experimental results. Correlation relations for heat flux distributions at the domain boundaries depending on Rayleigh and Ostrogradskii numbers are obtained. It is shown that generally heat transfer is governed both by natural circulation and crust formation phenomena. Results of this paper may be used for analysis of experiments with prototypic core materials.

  11. Improvement to the gas cycle energy generating installations with heat recuperation

    International Nuclear Information System (INIS)

    Tilliette, Zephyr.

    1977-01-01

    Improvement to the gas cycle energy generating installations with heat recuperation, comprising a heat source, supplying a fluid at high temperature and pressure, an expansion turbine, at least one recuperator fitted to the turbine outlet, a cooler and compressor in series, the compressor returning the high pressure fluid to the source after heat exchange in the recuperator with the low pressure fluid from the turbine. It is characterised in that at least one steam generator is connected to the low pressure end of the recuperator [fr

  12. Analysis and Modeling of Heat Generation in Overcharged Li-Ion Battery with Passive Cooling

    DEFF Research Database (Denmark)

    Coman, Paul Tiberiu; Veje, Christian

    2013-01-01

    This paper presents a dynamic model for simulating the heat generation in Lithium batteries and an investigation of the heat transfer as well as the capacity of Phase Change Materials (PCM’s) to store energy inside a battery cell module when the battery is overcharged. The study is performed......-cooled and passively cooled using a PCM, respectively. As expected, the results show that for high currents, the heat generation and implicitly the temperature increases. However, using a PCM the temperature increase is found to be limited allowing the battery to be overcharged to a certain degree. It is found...

  13. Heat generation and cooling of SSC magnets at high ramp rates

    International Nuclear Information System (INIS)

    Snitchler, G.; Capone, D.; Kovachev, V.; Schermer, R.

    1992-01-01

    This presentation will address a summary of AC loss calculations (SSCL), experimental results on cable samples (Westinghouse STC), short model magnets test results (FNAL, KEK-Japan), and recent full length magnets test data on AC losses and quench current ramp rate sensitivity (FNAL, BNL). Possible sources of the observed enhanced heat generation and quench sensitivity for some magnets will be discussed. A model for cooling conditions of magnet coils considering heat generation distribution and specific anisotropy of the heat transfer will be presented. The crossover contact resistance in cables and curing procedure influence on resistivity, currently under study, will be briefly discussed. (author)

  14. Local entropy generation analysis of a rotary magnetic heat pump regenerator

    International Nuclear Information System (INIS)

    Drost, M.K.; White, M.D.

    1990-01-01

    The rotary magnetic heat pump has attractive thermodynamic performance but it is strongly influenced by the effectiveness of the regenerator. This paper uses local entropy generation analysis to evaluate the regenerator design and to suggest design improvements. The results show that performance of the proposed design is dominated by heat transfer related entropy generation. This suggests that enhancement concepts that improve heat transfer should be considered, even if the enhancement causes a significant increase in viscous losses (pressure drop). One enhancement technique, the use of flow disruptors, was evaluated and the results showed that flow disruptors can significantly reduce thermodynamic losses

  15. Properties of Douglas Point Generating Station heat transport corrosion products

    International Nuclear Information System (INIS)

    Montford, B.; Rummery, T.E.

    1975-09-01

    Chemical, radiochemical and structural properties of circulating and fixed corrosion products from the Douglas Point Generating Station are documented. Interaction of Monel-400 and carbon steel corrosion products is described, and the mechanisms of Monel-400 surface deposit release, and activity buildup in the coolant system, are briefly discussed. Efficiencies of filters and ion-exchangers for the removal of released radionuclides are given. (author)

  16. Thermodynamic analysis of heat recovery steam generator in combined cycle power plant

    Directory of Open Access Journals (Sweden)

    Ravi Kumar Naradasu

    2007-01-01

    Full Text Available Combined cycle power plants play an important role in the present energy sector. The main challenge in designing a combined cycle power plant is proper utilization of gas turbine exhaust heat in the steam cycle in order to achieve optimum steam turbine output. Most of the combined cycle developers focused on the gas turbine output and neglected the role of the heat recovery steam generator which strongly affects the overall performance of the combined cycle power plant. The present paper is aimed at optimal utilization of the flue gas recovery heat with different heat recovery steam generator configurations of single pressure and dual pressure. The combined cycle efficiency with different heat recovery steam generator configurations have been analyzed parametrically by using first law and second law of thermodynamics. It is observed that in the dual cycle high pressure steam turbine pressure must be high and low pressure steam turbine pressure must be low for better heat recovery from heat recovery steam generator.

  17. Combined generation of electric and heating energy in future development of Yugoslav energy sector until 2000

    International Nuclear Information System (INIS)

    Djajic, Nenad; Zivanovic, Vladimir

    2000-01-01

    Development of the district heating system in the FR Yugoslavia, beside the combined generation of electric and heating energy presents a necessity for energy, economic and ecological reasons. Although the structure of energy reserves is rather unfavourable considering that the lignite is being predominantly used, available reserves of energy raw material are able to ensure the long-term development of Yugoslav energy sector, and to offer real possibilities for considerable substitution of foreign good quality fuels, especially in district heating systems. Their further development will depend, among other things: on the implementation of new technological solutions for the exploitation of local energy resources; need of reconstruction, revitalisation and transformation of old condensing thermal power plants into the cogeneration plants; installation of remote controlled transmission of heating energy as well as on development of heating plants and smaller co-generation plants based on local energy resources. (Authors)

  18. Transportation risk assessment of radioactive wastes generated by the N-Reactor stabilization program at the Hanford Site, Washington

    International Nuclear Information System (INIS)

    Wheeler, T.

    1994-12-01

    The potential radiological and nonradiological risks associated with specific radioactive waste shipping campaigns at the Hanford Site are estimated. The shipping campaigns analyzed are associated with the transportation of wastes from the N-Reactor site at the 200-W Area, both within the Hanford Reservation, for disposal. The analysis is based on waste that would be generated from the N-Reactor stabilization program

  19. Radioactive contamination and health risk assessment due to burning of coal in thermal energy generation

    International Nuclear Information System (INIS)

    Kant, K.

    2008-01-01

    Full text: Radon being a ubiquitous air pollutant has global impact and its monitoring in the environment at work places is essential from health and hygiene point of view. In thermal power plants, a lot of coal is burnt which contains radionuclides which are released into the environment and are hazardous. Radon is the main culprit in the local radioactive contamination of the environment due to burning of coal in thermal energy generation. It has been reported by several researchers (Nikl and Vegvari 1992, Bodizs et al. 1992) that the concentrations of the isotopes U 238 and Ra 226 become 3-5 times more than those in the coal itself in the coal slag and fly ash obtained by burning the coal in coal fired power plants. Several researchers have reported radon levels in thermal power plants (Bodizs et al. 1992, Rawat et al. 1991, Nikl and Vevgari 1992, Papastefanou and Charalanbous 1979, Kant et al. 2001). Keeping in view the environmental pollution caused due to the burning of coal in thermal power stations, there is an upsurge in the establishment of nuclear and gas turbine power stations in recent times. An increased share of gas and nuclear in power generation could lead to lower emissions. Also, considerable emphasis is being laid on developing non-polluting and renewable energy sources like water, air, solar energy and others. In this study, measurement of radon and its progeny levels was carried out over long integrated times in thermal power plant in Haryana by using LR-115, Type- II (Kodak Pathe, France), plastic track detectors commonly known as solid state nuclear track detectors (SS NTDs). Alpha particles emitted from radon cause radiation damage tracks, which were subsequently revealed by chemical etching in NaOH. These alpha tracks registered were counted by optical microscope at suitable magnification and converted into radon concentration. The findings indicate that it is very important to carry out these studies and the results of the full study will

  20. Study on heat pipe assisted thermoelectric power generation system from exhaust gas

    Science.gov (United States)

    Chi, Ri-Guang; Park, Jong-Chan; Rhi, Seok-Ho; Lee, Kye-Bock

    2017-11-01

    Currently, most fuel consumed by vehicles is released to the environment as thermal energy through the exhaust pipe. Environmentally friendly vehicle technology needs new methods to increase the recycling efficiency of waste exhaust thermal energy. The present study investigated how to improve the maximum power output of a TEG (Thermoelectric generator) system assisted with a heat pipe. Conventionally, the driving energy efficiency of an internal combustion engine is approximately less than 35%. TEG with Seebeck elements is a new idea for recycling waste exhaust heat energy. The TEG system can efficiently utilize low temperature waste heat, such as industrial waste heat and solar energy. In addition, the heat pipe can transfer heat from the automobile's exhaust gas to a TEG. To improve the efficiency of the thermal power generation system with a heat pipe, effects of various parameters, such as inclination angle, charged amount of the heat pipe, condenser temperature, and size of the TEM (thermoelectric element), were investigated. Experimental studies, CFD simulation, and the theoretical approach to thermoelectric modules were carried out, and the TEG system with heat pipe (15-20% charged, 20°-30° inclined configuration) showed the best performance.

  1. Study of heat diffusion in a granitic geologic formation of high level radioactive wastes

    International Nuclear Information System (INIS)

    Goldstein, S.; Juignet, N.

    1980-06-01

    Thermal study of granitic underground storage of vitrified high level radioactive wastes in a regular network of shafts and galleries. The aim is to show influence on temperature rise of the geologic formation of main parameters to define the storage zone and to determine the network dimension in function of the rock properties. Two models were studied allowing a rapid variation of geometrical and physical parameters. A numerical method using finite element method or Green functions were used for calculations. Temperatures are determined either for the whole storage site or a unit cell of the lattice [fr

  2. Practical aspects of heat transfer in radioactive-waste repository design

    International Nuclear Information System (INIS)

    Deane, J.S.; Hollis, A.A.

    1979-01-01

    An assessment has been made of the effect on temperature rises of the practical features associated with the disposal of high-level radioactive wastes in a repository constructed within a granite formation. Encapsulation, the use of a backfill material, and reduction in the axial spacing between blocks to 8m will have little effect on temperature rises. On the other hand thermal conductivity does have a marked effect on the temperature rises in the granite, and there is clear need for the measurement of granite thermal conductivity at selected sites. (author)

  3. Next Generation Nuclear Plant Intermediate Heat Exchanger Materials Research and Development Plan (PLN-2804)

    Energy Technology Data Exchange (ETDEWEB)

    J. K. Wright

    2008-04-01

    DOE has selected the High Temperature Gas-cooled Reactor (HTGR) design for the Next Generation Nuclear Plant (NGNP) Project. The NGNP will demonstrate the use of nuclear power for electricity and hydrogen production. It will have an outlet gas temperature in the range of 900°C and a plant design service life of 60 years. The reactor design will be a graphite moderated, helium-cooled, prismatic or pebble-bed reactor and use low-enriched uranium, Tri-Isotopic (TRISO)-coated fuel. The plant size, reactor thermal power, and core configuration will ensure passive decay heat removal without fuel damage or radioactive material releases during accidents. The NGNP Materials Research and Development (R&D) Program is responsible for performing R&D on likely NGNP materials in support of the NGNP design, licensing, and construction activities. Today’s high-temperature alloys and associated ASME Codes for reactor applications are approved up to 760°C. However, some primary system components, such as the Intermediate Heat Exchanger (IHX) for the NGNP will require use of materials that can withstand higher temperatures. The thermal, environmental, and service life conditions of the NGNP will make selection and qualification of some high-temperature materials a significant challenge. Examples include materials for the core barrel and core internals, such as the control rod sleeves. The requirements of the materials for the IHX are among the most demanding. Selection of the technology and design configuration for the NGNP must consider both the cost and risk profiles to ensure that the demonstration plant establishes a sound foundation for future commercial deployments. The NGNP challenge is to achieve a significant advancement in nuclear technology while at the same time setting the stage for an economically viable deployment of the new technology in the commercial sector soon after 2020. A number of solid solution strengthened nickel based alloys have been considered for

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

    Science.gov (United States)

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

    2006-06-27

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

  5. Encouragement of Enzyme Reaction Utilizing Heat Generation from Ferromagnetic Particles Subjected to an AC Magnetic Field.

    Science.gov (United States)

    Suzuki, Masashi; Aki, Atsushi; Mizuki, Toru; Maekawa, Toru; Usami, Ron; Morimoto, Hisao

    2015-01-01

    We propose a method of activating an enzyme utilizing heat generation from ferromagnetic particles under an ac magnetic field. We immobilize α-amylase on the surface of ferromagnetic particles and analyze its activity. We find that when α-amylase/ferromagnetic particle hybrids, that is, ferromagnetic particles, on which α-amylase molecules are immobilized, are subjected to an ac magnetic field, the particles generate heat and as a result, α-amylase on the particles is heated up and activated. We next prepare a solution, in which α-amylase/ferromagnetic particle hybrids and free, nonimmobilized chitinase are dispersed, and analyze their activities. We find that when the solution is subjected to an ac magnetic field, the activity of α-amylase immobilized on the particles increases, whereas that of free chitinase hardly changes; in other words, only α-amylase immobilized on the particles is selectively activated due to heat generation from the particles.

  6. Encouragement of Enzyme Reaction Utilizing Heat Generation from Ferromagnetic Particles Subjected to an AC Magnetic Field.

    Directory of Open Access Journals (Sweden)

    Masashi Suzuki

    Full Text Available We propose a method of activating an enzyme utilizing heat generation from ferromagnetic particles under an ac magnetic field. We immobilize α-amylase on the surface of ferromagnetic particles and analyze its activity. We find that when α-amylase/ferromagnetic particle hybrids, that is, ferromagnetic particles, on which α-amylase molecules are immobilized, are subjected to an ac magnetic field, the particles generate heat and as a result, α-amylase on the particles is heated up and activated. We next prepare a solution, in which α-amylase/ferromagnetic particle hybrids and free, nonimmobilized chitinase are dispersed, and analyze their activities. We find that when the solution is subjected to an ac magnetic field, the activity of α-amylase immobilized on the particles increases, whereas that of free chitinase hardly changes; in other words, only α-amylase immobilized on the particles is selectively activated due to heat generation from the particles.

  7. Power generation and heating performances of integrated system of ammonia–water Kalina–Rankine cycle

    International Nuclear Information System (INIS)

    Zhang, Zhi; Guo, Zhanwei; Chen, Yaping; Wu, Jiafeng; Hua, Junye

    2015-01-01

    Highlights: • Integrated system of ammonia–water Kalina–Rankine cycle (AWKRC) is investigated. • Ammonia–water Rankine cycle is operated for cogenerating room heating-water in winter. • Kalina cycle with higher efficiency is operated for power generation in other seasons. • Power recovery efficiency accounts thermal efficiency and waste heat absorbing ratio. • Heating water with 70 °C and capacity of 55% total reclaimed heat load is cogenerated. - Abstract: An integrated system of ammonia–water Kalina–Rankine cycle (AWKRC) for power generation and heating is introduced. The Kalina cycle has large temperature difference during evaporation and small one during condensation therefore with high thermal efficiency for power generation, while the ammonia–water Rankine cycle has large temperature difference during condensation as well as evaporation, thus it can be adopted to generate heating-water as a by-product in winter. The integrated system is based on the Kalina cycle and converted to the Rankine cycle with a set of valves. The performances of the AWKRC system in different seasons with corresponding cycle loops were studied and analyzed. When the temperatures of waste heat and cooling water are 300 °C and 25 °C respectively, the thermal efficiency and power recovery efficiency of Kalina cycle are 20.9% and 17.4% respectively in the non-heating seasons, while these efficiencies of the ammonia–water Rankine cycle are 17.1% and 13.1% respectively with additional 55.3% heating recovery ratio or with comprehensive efficiency 23.7% higher than that of the Kalina cycle in heating season

  8. Generation and sustainment of plasma rotation by ICRF heating

    International Nuclear Information System (INIS)

    Perkins, F.W.; White, R.; Bonoli, P.T.; Chan, V.S.

    2001-01-01

    A mechanism is proposed and evaluated for driving rotation in tokamak plasmas by minority ion-cyclotron heating, even though this process introduces negligible angular momentum. The mechanism has two elements: First, angular momentum transport is governed by a diffusion equation with a non-slip boundary condition at the separatrix. Second, Monte-Carlo calculations show that energized particles will provide a torque density source which has a zero volume integral but separated positive and negative regions. With such a source, a solution of the diffusion equation predicts the on-axis rotation frequency Ω to be Ω=(4q max WJ*)eBR 3 a 2 n e (2π) 2 ) -1 (τ M /τ E ) where vertical bar J* vertical bar ∼ 5-10 is a non-dimensional rotation frequency calculated by the Monte-Carlo ORBIT code. Overall, agreement with experiment is good, when the resonance is on the low-field-side of the magnetic axis. The rotation becomes more counter-current and reverses sign on the high field side for a no-slip boundary. The velocity shear layer position is controllable and of sufficient magnitude to affect microinstabilities. (author)

  9. Experimental investigation of natural convection induced by internal heat generation

    International Nuclear Information System (INIS)

    Tasaka, Y; Kudoh, Y; Takeda, Y; Yanagisawa, T

    2005-01-01

    Dilatation of a convection cell with respect to its Rayleigh number, one of the problems in internally heated convection, was quantitatively investigated by analyzing temperature field in a cell. The temperature field visualized by a thermo-chromic liquid crystal (TLC) expresses the cell dilatation. A calibration system was developed to convert the visualized photographs of the temperature field to the temperature field. A calibration curve correlating color information extracted from the photograph and temperature was determined from the approximately linear temperature distribution in the horizontal fluid layer using the hue method. Photos taken at various internal Rayleigh numbers were converted to the temperature field by the obtained curve. Extracting individual cells from a temperature field achieves a quantitative expression of the cell dilatation as the variation of the wavenumber of the cell with Rayleigh number increases. The temperature profile in a cell shows that high temperature areas appear at the apexes of the cell, largely different from the profile obtained by linear theory

  10. Technology for Treatment of Liquid Radioactive Waste Generated during Uranium and Plutonium Chemical and Metallurgical Manufacturing in FSUE PO Mayak - 13616

    Energy Technology Data Exchange (ETDEWEB)

    Adamovich, D. [SUE MosSIA Radon, 2/14 7th Rostovsky lane, Moscow, 119121 (Russian Federation); Batorshin, G.; Logunov, M.; Musalnikov, A. [FSUE ' PO Mayak' , 31 av. Lenin, Ozyorsk, Chelyabinsk region, 456780 (Russian Federation)

    2013-07-01

    Created technological scheme for treatment of liquid radioactive waste generated while uranium and plutonium chemical and metallurgical manufacturing consists of: - Liquid radioactive waste (LRW) purification from radionuclides and its transfer into category of manufacturing waste; - Concentration of suspensions containing alpha-nuclides and their further conversion to safe dry state (calcinate) and moving to long controlled storage. The following technologies are implemented in LRW treatment complex: - Settling and filtering technology for treatment of liquid intermediate-level waste (ILW) with volume about 1500m{sup 3}/year and alpha-activity from 10{sup 6} to 10{sup 8} Bq/dm{sup 3} - Membrane and sorption technology for processing of low-level waste (LLW) of radioactive drain waters with volume about 150 000 m{sup 3}/year and alpha-activity from 10{sup 3} to 10{sup 4} Bq/dm{sup 3}. Settling and filtering technology includes two stages of ILW immobilization accompanied with primary settling of radionuclides on transition metal hydroxides with the following flushing and drying of the pulp generated; secondary deep after settling of radionuclides on transition metal hydroxides with the following solid phase concentration by the method of tangential flow ultrafiltration. Besides, the installation capacity on permeate is not less than 3 m{sup 3}/h. Concentrates generated are sent to calcination on microwave drying (MW drying) unit. Membrane and sorption technology includes processing of averaged sewage flux by the method of tangential flow ultrafiltration with total capacity of installations on permeate not less than 18 m{sup 3}/h and sorption extraction of uranium from permeate on anionite. According to radionuclide contamination level purified solution refers to general industrial waste. Concentrates generated during suspension filtering are evaporated in rotary film evaporator (RFE) in order to remove excess water, thereafter they are dried on infrared heating

  11. Roadmapping the Resolution of Gas Generation Issues in Packages Containing Radioactive Waste/Materials - A Status Report

    International Nuclear Information System (INIS)

    Luke, D.E.; Hamp, S.

    2002-01-01

    Gas generation issues, particularly hydrogen, have been an area of concern for the transport and storage of radioactive materials and waste in the Department of Energy (DOE) Complex. Potentially combustible gases can be generated through a variety of reactions, including chemical reactions and radiolytic decomposition of hydrogen-containing material. Since transportation regulations prohibit shipment of explosives and radioactive materials together, it was decided that hydrogen generation was a problem that warranted the execution of a high-level roadmapping effort. This paper discusses the major gas generation issues within the DOE Complex and the research that has been and is being conducted by the transuranic (TRU) waste, nuclear materials, and spent nuclear fuels (SNF) programs within DOE's Environmental Management (EM) organizations to address gas generation concerns. This paper presents a ''program level'' roadmap that links technology development to program needs and identifies the probability of success in an effort to understand the programmatic risk associated with the issue of gas generation. This paper also presents the status of the roadmap and follow-up activities

  12. Steady-state heat transfer in an inverted U-tube steam generator

    International Nuclear Information System (INIS)

    Boucher, T.J.

    1986-01-01

    Experimental results are presented involving U-tube steam generator tube bundle local heat transfer and fluid conditions during steady-state, full-power operations performed at high temperatures and pressures with conditions typical of a pressurized water reactor (15.0 MPa primary pressure, 600 K hot-leg fluid temperatures, 6.2 MPa secondary pressure). The MOD-2C facility represents the state-of-the-art in measurement of tube local heat transfer data and average tube bundle secondary fluid density at several elevations, which allows an estimate of the axial heat transfer and void distributions during steady-state and transient operations. The method of heat transfer data reduction is presented and the heat flux, secondary convective heat transfer coefficient, and void fraction distributions are quantified for steady-state, full-power operations

  13. Heat savings and heat generation technologies: Modelling of residential investment behaviour with local health costs

    DEFF Research Database (Denmark)

    Zvingilaite, Erika; Klinge Jacobsen, Henrik

    2015-01-01

    The trade-off between investing in energy savings and investing in individual heating technologies with high investment and low variable costs in single family houses is modelled for a number of building and consumer categories in Denmark. For each group the private economic cost of providing hea...... for private consumers decrease by 66% when all have the option to shift to the technology with lowest variable costs. © 2014 Elsevier Ltd. All Rights reserved......The trade-off between investing in energy savings and investing in individual heating technologies with high investment and low variable costs in single family houses is modelled for a number of building and consumer categories in Denmark. For each group the private economic cost of providing...

  14. Membrane-based osmotic heat engine with organic solvent for enhanced power generation from low-grade heat.

    Science.gov (United States)

    Shaulsky, Evyatar; Boo, Chanhee; Lin, Shihong; Elimelech, Menachem

    2015-05-05

    We present a hybrid osmotic heat engine (OHE) system that uses draw solutions with an organic solvent for enhanced thermal separation efficiency. The hybrid OHE system produces sustainable energy by combining pressure-retarded osmosis (PRO) as a power generation stage and membrane distillation (MD) utilizing low-grade heat as a separation stage. While previous OHE systems employed aqueous electrolyte draw solutions, using methanol as a solvent is advantageous because methanol is highly volatile and has a lower heat capacity and enthalpy of vaporization than water. Hence, the thermal separation efficiency of a draw solution with methanol would be higher than that of an aqueous draw solution. In this study, we evaluated the performance of LiCl-methanol as a potential draw solution for a PRO-MD hybrid OHE system. The membrane transport properties as well as performance with LiCl-methanol draw solution were evaluated using thin-film composite (TFC) PRO membranes and compared to the results obtained with a LiCl-water draw solution. Experimental PRO methanol flux and maximum projected power density of 47.1 L m(-2) h(-1) and 72.1 W m(-2), respectively, were achieved with a 3 M LiCl-methanol draw solution. The overall efficiency of the hybrid OHE system was modeled by coupling the mass and energy flows between the thermal separation (MD) and power generation (PRO) stages under conditions with and without heat recovery. The modeling results demonstrate higher OHE energy efficiency with the LiCl-methanol draw solution compared to that with the LiCl-water draw solution under practical operating conditions (i.e., heat recovery<90%). We discuss the implications of the results for converting low-grade heat to power.

  15. Membrane-Based Osmotic Heat Engine with Organic Solvent for Enhanced Power Generation from Low-Grade Heat

    Energy Technology Data Exchange (ETDEWEB)

    Shaulsky, E; Boo, C; Lin, SH; Elimelech, M

    2015-05-05

    We present a hybrid osmotic heat engine (OHE) system that uses draw solutions with an organic solvent for enhanced thermal separation efficiency. The hybrid OHE system produces sustainable energy by combining pressure-retarded osmosis (PRO) as a power generation stage and membrane distillation (MD) utilizing low-grade heat as a separation stage. While previous OHE systems employed aqueous electrolyte draw solutions, using methanol as a solvent is advantageous because methanol is highly volatile and has a lower heat capacity and enthalpy of vaporization than water. Hence, the thermal separation efficiency of a draw solution with methanol would be higher than that of an aqueous draw solution. In this study, we evaluated the performance of LiCl-methanol as a potential draw solution for a PRO-MD hybrid OHE system. The membrane transport properties as well as performance with LiCl methanol draw solution were evaluated using thin-film composite (TFC) PRO membranes and compared to the results obtained with a LiCl water draw solution. Experimental PRO methanol flux and maximum projected power density of 47.1 L m(-2) h(-1) and 72.1 W m(-2), respectively, were achieved with a 3 M LiCl-methanol draw solution. The overall efficiency of the hybrid OHE system was modeled by coupling the mass and energy flows between the thermal separation (MD) and power generation (PRO) stages under conditions with and without heat recovery. The modeling results demonstrate higher ORE energy efficiency with the LiCl methanol draw solution compared to that with the LiCl water draw solution under practical operating conditions (i.e., heat recovery <90%). We discuss the implications of the results for converting low-grade heat to power.

  16. Entropy Generation Analysis and Performance Evaluation of Turbulent Forced Convective Heat Transfer to Nanofluids

    Directory of Open Access Journals (Sweden)

    Yu Ji

    2017-03-01

    Full Text Available The entropy generation analysis of fully turbulent convective heat transfer to nanofluids in a circular tube is investigated numerically using the Reynolds Averaged Navier–Stokes (RANS model. The nanofluids with particle concentration of 0%, 1%, 2%, 4% and 6% are treated as single phases of effective properties. The uniform heat flux is enforced at the tube wall. To confirm the validity of the numerical approach, the results have been compared with empirical correlations and analytical formula. The self-similarity profiles of local entropy generation are also studied, in which the peak values of entropy generation by direct dissipation, turbulent dissipation, mean temperature gradients and fluctuating temperature gradients for different Reynolds number as well as different particle concentration are observed. In addition, the effects of Reynolds number, volume fraction of nanoparticles and heat flux on total entropy generation and Bejan number are discussed. In the results, the intersection points of total entropy generation for water and four nanofluids are observed, when the entropy generation decrease before the intersection and increase after the intersection as the particle concentration increases. Finally, by definition of Ep, which combines the first law and second law of thermodynamics and attributed to evaluate the real performance of heat transfer processes, the optimal Reynolds number Reop corresponding to the best performance and the advisable Reynolds number Read providing the appropriate Reynolds number range for nanofluids in convective heat transfer can be determined.

  17. Exergetic life cycle assessment of cement production process with waste heat power generation

    International Nuclear Information System (INIS)

    Sui, Xiuwen; Zhang, Yun; Shao, Shuai; Zhang, Shushen

    2014-01-01

    Highlights: • Exergetic life cycle assessment was performed for the cement production process. • Each system’s efficiency before and after waste heat power generation was analyzed. • The waste heat power generation improved the efficiency of each production system. • It provided technical support for the implementation of energy-saving schemes. - Abstract: The cement industry is an industry that consumes a considerable quantity of resources and energy and has a very large influence on the efficient use of global resources and energy. In this study, exergetic life cycle assessment is performed for the cement production process, and the energy efficiency and exergy efficiency of each system before and after waste heat power generation is investigated. The study indicates that, before carrying out a waste heat power generation project, the objective energy efficiencies of the raw material preparation system, pulverized coal preparation system and rotary kiln system are 39.4%, 10.8% and 50.2%, respectively, and the objective exergy efficiencies are 4.5%, 1.4% and 33.7%, respectively; after carrying out a waste heat power generation project, the objective energy efficiencies are 45.8%, 15.5% and 55.1%, respectively, and the objective exergy efficiencies are 7.8%, 2.8% and 38.1%, respectively. The waste heat power generation project can recover 3.7% of the total input exergy of a rotary kiln system and improve the objective exergy efficiencies of the above three systems. The study can identify degree of resource and energy utilization and the energy-saving effect of a waste heat power generation project on each system, and provide technical support for managers in the implementation of energy-saving schemes

  18. CHP in Switzerland from 1990 to 1998. Thermal power generation including combined heat and power

    International Nuclear Information System (INIS)

    Kaufmann, U.

    1999-01-01

    The results of a study on thermal power generation in Switzerland show that combined heat and power (CHP) systems have grown rapidly. Statistics are presented on the development of CHP-based power and also on thermal power stations without waste heat usage. Figures are given for gas and steam turbine installations, combined gas and steam turbine stations and motor-driven CHP units. Power production is categorised, separating small and large (over 1 Megawatt electrical) power generation facilities. On-site, distributed power generation at consumers' premises and the geographical distribution of plant is described

  19. MHTGR steam generator on-line heat balance, instrumentation and function

    International Nuclear Information System (INIS)

    Klapka, R.E.; Howard, W.W.; Etzel, K.T.; Basol, M.; Karim, N.U.

    1991-09-01

    Instrumentation is used to measure the Modular High Temperature Gas-Cooled Reactor (MHTGR) steam generator dissimilar metal weld temperature during start-up testing. Additional instrumentation is used to determine an on-line heat balance which is maintained during the 40 year module life. In the process of calibrating the on-line heat balance, the helium flow is adjusted to yield the optimum boiling level in the steam generator relative to the dissimilar metal weld. After calibration is complete the weld temperature measurement is non longer required. The reduced boiling level range results in less restrictive steam generator design constraints

  20. Specification of steam generator, condenser and regenerative heat exchanger materials for nuclear applications

    International Nuclear Information System (INIS)

    Jovasevic, J.V.; Stefanovic, V.M.; Spasic, Z.LJ.

    1977-01-01

    The basic standards specifications of materials for nuclear applications are selected. Seamless Ni-Cr-Fe alloy Tubes (Inconel-600) for steam generators, condensers and other heat exchangers can be employed instead of austenitic stainless steal or copper alloys tubes; supplementary requirements for these materials are given. Specifications of Ni-Cr-Fe alloy plate, sheet and strip for steam generator lower sub-assembly, U-bend seamless copper-alloy tubes for heat exchanger and condensers are also presented. At the end, steam generator channel head material is proposed in the specification for carbon-steel castings suitable for welding

  1. Design option of heat exchanger for the next generation nuclear plant - HTR2008-58175

    International Nuclear Information System (INIS)

    Oh, C. H.; Kim, E. S.

    2008-01-01

    The Next Generation Nuclear Plant (NGNP), a very High temperature Gas-Cooled Reactor (VHTR) concept, will provide the first demonstration of a closed-loop Brayton cycle at a commercial scale, producing a few hundred megawatts of power in the form of electricity and hydrogen. The power conversion unit (PCU) for the NGNP will take advantage of the significantly higher reactor outlet temperatures of the VHTRs to provide higher efficiencies than can be achieved with the current generation of light water reactors. Besides demonstrating a system design that can be used directly for subsequent commercial deployment, the NGNP will demonstrate key technology elements that can be used in subsequent advanced power conversion systems for other Generation IV reactors. In anticipation of the design, development and procurement of an advanced power conversion system for the NGNP, the system integration of the NGNP and hydrogen plant was initiated to identify the important design and technology options that must be considered in evaluating the performance of the proposed NGNP. As part of the system integration of the VHTRs and the hydrogen production plant, the intermediate heat exchanger is used to transfer the process heat from VHTRs to the hydrogen plant. Therefore, the design and configuration of the intermediate heat exchanger is very important. This paper will include analysis of one stage versus two stage heat exchanger design configurations and simple stress analyses of a printed circuit heat exchanger (PCHE), helical coil heat exchanger, and shell/tube heat exchanger. (authors)

  2. A methodology for the geometric design of heat recovery steam generators applying genetic algorithms

    International Nuclear Information System (INIS)

    Durán, M. Dolores; Valdés, Manuel; Rovira, Antonio; Rincón, E.

    2013-01-01

    This paper shows how the geometric design of heat recovery steam generators (HRSG) can be achieved. The method calculates the product of the overall heat transfer coefficient (U) by the area of the heat exchange surface (A) as a function of certain thermodynamic design parameters of the HRSG. A genetic algorithm is then applied to determine the best set of geometric parameters which comply with the desired UA product and, at the same time, result in a small heat exchange area and low pressure losses in the HRSG. In order to test this method, the design was applied to the HRSG of an existing plant and the results obtained were compared with the real exchange area of the steam generator. The findings show that the methodology is sound and offers reliable results even for complex HRSG designs. -- Highlights: ► The paper shows a methodology for the geometric design of heat recovery steam generators. ► Calculates product of the overall heat transfer coefficient by heat exchange area as a function of certain HRSG thermodynamic design parameters. ► It is a complement for the thermoeconomic optimization method. ► Genetic algorithms are used for solving the optimization problem

  3. Heat generation and hemolysis at the shaft seal in centrifugal blood pumps.

    Science.gov (United States)

    Araki, K; Taenaka, Y; Wakisaka, Y; Masuzawa, T; Tatsumi, E; Nakatani, T; Baba, Y; Yagura, A; Eya, K; Toda, K

    1995-01-01

    The heat and hemolysis around a shaft seal were investigated. Materials were original pumps (Nikkiso HMS-15:N-original, and 3M Delphin:D-original), vane-removed pumps (Nvane(-), Dvane(-)), and a small chamber with a shaft coiled by nichrome wire (mock pump). The original pumps were driven at 500 mmHg and 5 L/min, and vane-removed pumps were driven at the same rotation number. An electrical powers of 0, 0.5, 2, and 10 W was supplied to the mock pumps. In vitro hemolytic testing showed that hemolytic indices were 0.027 g/100 L in N-original, 0.013 in Nvane(-), 0.061 in D-original, and 0.012 in Dvane(-). Measurement of heat with a thermally insulated water chamber showed total heat within the pump of 8.62 and 10.85 W, and heat at the shaft seal of 0.87 and 0.62 W in the Nikkiso and Delphin pumps, respectively. Hemolysis and heat generation of mock pumps remained low. The results indicate that the heat generated around the shaft seal was minimal. Hemolysis at the shaft-seal was considerable but not major. Local heat did not affect hemolysis. It was concluded that the shaft-seal affected hemolysis, not by local heat but friction itself.

  4. Origin of excess heat generated during loading Pd-impregnated alumina powder with deuterium and hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Dmitriyeva, O., E-mail: olga.dmitriyeva@colorado.edu [Department of Electrical, Computer, and Energy Engineering, University of Colorado, Boulder, CO 80309-0425 (United States); Coolescence LLC, 2450 Central Ave Ste F, Boulder, CO 80301 (United States); Cantwell, R.; McConnell, M. [Coolescence LLC, 2450 Central Ave Ste F, Boulder, CO 80301 (United States); Moddel, G. [Department of Electrical, Computer, and Energy Engineering, University of Colorado, Boulder, CO 80309-0425 (United States)

    2012-09-10

    Highlights: Black-Right-Pointing-Pointer We studied heat produced by hydrogen and deuterium in Pd-impregnated alumina powder. Black-Right-Pointing-Pointer Samples were fabricated using light and heavy water isotopes and varied the gas used for loading. Black-Right-Pointing-Pointer Incorporation of hydrogen and deuterium influenced the amount of heat released or consumed. Black-Right-Pointing-Pointer Pd nanoparticles appear to catalyze hydrogen/deuterium (H/D) exchange chemical reactions. Black-Right-Pointing-Pointer Anomalous heating can be accounted for by chemical rather than nuclear reactions. - Abstract: We studied heat production in Pd-impregnated alumina powder in the presence of hydrogen and deuterium gases, investigating claims of anomalous heat generated as a result of nuclear fusion, usually referred to as a low energy nuclear reaction (LENR). By selecting the water isotope used to fabricate the material and then varying the gas used for loading, we were able to influence the amount of heat released or consumed. We suggest that Pd in its nanoparticle form catalyzes hydrogen/deuterium (H/D) exchange reactions in the material. This hypothesis is supported by heat measurements, residual gas analysis (RGA) data, and calculations of energy available from H/D exchange reactions. Based on the results we conclude that the origin of the anomalous heat generated during deuterium loading of Pd-enriched alumina powder is chemical rather than nuclear.

  5. Origin of excess heat generated during loading Pd-impregnated alumina powder with deuterium and hydrogen

    International Nuclear Information System (INIS)

    Dmitriyeva, O.; Cantwell, R.; McConnell, M.; Moddel, G.

    2012-01-01

    Highlights: ► We studied heat produced by hydrogen and deuterium in Pd-impregnated alumina powder. ► Samples were fabricated using light and heavy water isotopes and varied the gas used for loading. ► Incorporation of hydrogen and deuterium influenced the amount of heat released or consumed. ► Pd nanoparticles appear to catalyze hydrogen/deuterium (H/D) exchange chemical reactions. ► Anomalous heating can be accounted for by chemical rather than nuclear reactions. - Abstract: We studied heat production in Pd-impregnated alumina powder in the presence of hydrogen and deuterium gases, investigating claims of anomalous heat generated as a result of nuclear fusion, usually referred to as a low energy nuclear reaction (LENR). By selecting the water isotope used to fabricate the material and then varying the gas used for loading, we were able to influence the amount of heat released or consumed. We suggest that Pd in its nanoparticle form catalyzes hydrogen/deuterium (H/D) exchange reactions in the material. This hypothesis is supported by heat measurements, residual gas analysis (RGA) data, and calculations of energy available from H/D exchange reactions. Based on the results we conclude that the origin of the anomalous heat generated during deuterium loading of Pd-enriched alumina powder is chemical rather than nuclear.

  6. Technology data for electricity and heat generating plants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-03-01

    The Danish Energy Authority and the two Danish electricity transmission and system operators, Elkraft System and Eltra, initiated updating of current technology catalogues in 2003. The first updated catalogue was published in March 2004. This report presents the results of the second phase of updating. The primary objective has been to establish a uniform, commonly accepted and up-to-date basis for energy planning activities, such as future outlooks, evaluations of security of supply and environmental impacts, climate change evaluations, and technical and economic analyses. The catalogue may furthermore be used as reference for evaluations of the development perspectives for the numerous technologies available for energy generation in relation to the programming of funding schemes for research, development and demonstration of emerging technologies. It has finally been the intention to offer the catalogue for the international audience, as a contribution to similar initiates aiming at forming a public and concerted knowledge base for international analyses and negotiations. A guiding principle for developing the catalogue has been to primarily rely on well-documented and public information, secondarily on invited expert advice. Since many experts are reluctant in estimating future quantitative performance data, the data tables are not complete, in the sense that most data tables show several blank spaces. This approach has been chosen in order to achieve data, which to some extent are equivalently reliable, rather than to risk a largely incoherent data set including unfounded guesses. (au)

  7. Institutional innovation to generate the public acceptance of radioactive waste disposal

    International Nuclear Information System (INIS)

    Kemp, R.

    1991-01-01

    Contrasting experiences of public acceptance of radioactive waste disposal are compared for the United Kingdom, France, Sweden and Canada. The disparity between scientifically assessed and publicly perceived levels of risk is noted. The author argues that the form of decision-making process is more important to public acceptance of radioactive waste disposal than the technology of disposal. Public risk perception can be altered by procedures employed in planning, negotiation and consultation. Precisely what constitutes acceptable risk does vary from country to country, and differences in institutional responses and innovation are particularly highlighted. (UK)

  8. Governing equations for heat and mass transfer in heat-generating porous beds

    International Nuclear Information System (INIS)

    Chawla, T.C.; Pedersen, D.R.; Minkowycz, W.J.

    1985-01-01

    Upon dryout of the bed, the dominant modes of heat transfer are conduction and radiation. Radiation is modeled through the Rosseland approximation. The melting of stainless-steel particulate imbedded in the fuel is modeled by assuming the bed to be a continuum with conduction and radiation as the dominant modes of heat transfer. The molten steel, after it drains to the bottom of the bed, is assumed to disappear into cracks and mortar joints of the MgO bricks. The melting of fuel in the interior of the bed is modeled identically to the steel particulate, except for the bed settling which is more pronounced in the case of fuel melting and is assumed to be instantaneous owing to the significant weight of overlying bed and sodium pool. The molten layer of fuel, as it collects at the bottom of the bed, causes the heatup of the MgO lining to the eutectic temperature (2280 0 C), and the MgO lining begins to dissolve. The density gradient caused by the dissolution of MgO leads to natural convection and mixing in the molten layer. The submerged fuel particulate also begins to dissolve in the molten solution and ultimately leads to the conversion of debris to a molten pool of fuel and MgO. The process of penetration of the MgO lining continues until the mixing process lowers the concentration of fuel in the volume of the pool to the level where the internal heat rate per unit volume is not enough to keep the body of the pool molten and leads to freezing in the cooler part of the pool. As the molten pool reaches a frozen or a quiescent state, the MgO brick lining thickness provided is deemed 'safe' for a given bed loading and the external rate of cooling. (author)

  9. Radiative heat transfer in a heat generating and turbulently convecting fluid layer

    International Nuclear Information System (INIS)

    Cheung, F.B.; Chan, S.H.; Chawla, T.C.; Cho, D.H.

    1980-01-01

    The coupled problem of radiative transport and turbulent natural convection in a volumetrically heated, horizontal gray fluid medium, bounded from above by a rigid, isothermal wall and below by a rigid, adiabatic wall, is investigated analytically. An approximate method based upon the boundary layer approach is employed to obtain the dependence of heat transfer at the upper wall on the principal parameters of the problem, which, for moderate Prandtl number, are the Rayleigh number, Ra, the optical thickness, KL, and the conduction-radiation coupling parameter, N. Also obtained in this study is the behaviour of the thermal boundary layer at the upper wall. At large kL, the contribution of thermal radiation to heat transfer in the layer is found to be negligible for N > 10, moderate for N approximately 1, and overwhelming for N < 0.1. However, at small kL, thermal radiation is found to be important only for N < 0.01. While a higher level of turbulence results in a thinner boundary layer, a larger effect of radiation is found to result in a thicker one. Thus, in the presence of strong thermal radiation, a much larger value of Ra is required for the boundary layer approach to remain valid. Under severe radiation conditions, no boundary layer flow regime is found to exist even at very high Rayleigh numbers. Accordingly, the ranges of applicability of the present results are determined and the approximate method justified. In particular, the validity of the present analysis is tested in three limiting cases, ie those of kL → infinity, N → infinity, and Ra → infinity, and is further confirmed by comparison with the numerical solution (author)

  10. Heat generation caused by ablation of dental hard tissues with an ultrashort pulse laser (USPL) system.

    Science.gov (United States)

    Braun, Andreas; Krillke, Raphael Franz; Frentzen, Matthias; Bourauel, Christoph; Stark, Helmut; Schelle, Florian

    2015-02-01

    Heat generation during the removal of dental hard tissues may lead to a temperature increase and cause painful sensations or damage dental tissues. The aim of this study was to assess heat generation in dental hard tissues following laser ablation using an ultrashort pulse laser (USPL) system. A total of 85 specimens of dental hard tissues were used, comprising 45 specimens of human dentine evaluating a thickness of 1, 2, and 3 mm (15 samples each) and 40 specimens of human enamel with a thickness of 1 and 2 mm (20 samples each). Ablation was performed with an Nd:YVO4 laser at 1,064 nm, a pulse duration of 9 ps, and a repetition rate of 500 kHz with an average output power of 6 W. Specimens were irradiated for 0.8 s. Employing a scanner system, rectangular cavities of 1-mm edge length were generated. A temperature sensor was placed at the back of the specimens, recording the temperature during the ablation process. All measurements were made employing a heat-conductive paste without any additional cooling or spray. Heat generation during laser ablation depended on the dental hard tissue (enamel or dentine) and the thickness of the respective tissue (p dental hard tissues, heat generation has to be considered. Especially during laser ablation next to pulpal tissues, painful sensations and potential thermal injury of pulp tissue might occur.

  11. A thermoelectric generator using loop heat pipe and design match for maximum-power generation

    KAUST Repository

    Huang, Bin-Juine; Hsu, Po-Chien; Tsai, Rung-Je; Hussain, Muhammad Mustafa

    2015-01-01

    of noise. The experiments for a TEG with 4W rated power show that the LHP performs very well with overall thermal resistance 0.35 K W-1, from the cold side of TEG module to the ambient. The LHP is able to dissipate heat up to 110W and is maintenance free

  12. Radioactive liquid containing vessel

    International Nuclear Information System (INIS)

    Sakurada, Tetsuo; Kawamura, Hironobu.

    1993-01-01

    Cooling jackets are coiled around the outer circumference of a container vessel, and the outer circumference thereof is covered with a surrounding plate. A liquid of good conductivity (for example, water) is filled between the cooling jackets and the surrounding plate. A radioactive liquid is supplied to the container vessel passing through a supply pipe and discharged passing through a discharge pipe. Cooling water at high pressure is passed through the cooling water jackets in order to remove the heat generated from the radioactive liquid. Since cooling water at high pressure is thus passed through the coiled pipes, the wall thickness of the container vessel and the cooling water jackets can be reduced, thereby enabling to reduce the cost. Further, even if the radioactive liquid is leaked, there is no worry of contaminating cooling water, to prevent contamination. (I.N.)

  13. Modelling of radionuclide migration and heat transport from an High-Level-Radioactive-Waste-repository (HLW) in Boom clay

    International Nuclear Information System (INIS)

    Put, M.; Henrion, P.

    1992-01-01

    For the modelling of the migration of radionuclides in the Boom clay formation, the analytical code MICOF has been updated with a 3-dimensional analytical solution for discrete sources. the MICOF program is used for the calculation of the release of α and β emitters from the HIGH LEVEL RADIOACTIVE WASTES (HLW). A coherent conceptual model is developed which describes all the major physico-chemical phenomena influencing the migration of radionuclides in the Boom clay. The concept of the diffusion accessible porosity is introduced and included in the MICOF code. Different types of migration experiments are described with their advantages and disadvantages. The thermal impact of the HLW disposal in the stratified Boom clay formation has been evaluated by a finite element simulation of the coupled heat and mass transport equation. The results of the simulations show that under certain conditions thermal convection cells may form, but the convective heat transfer in the clay formation is negligible. 6 refs., 19 figs., 2 tabs., 5 appendices

  14. Thermal power generation projects ``Large Scale Solar Heating``; EU-Thermie-Projekte ``Large Scale Solar Heating``

    Energy Technology Data Exchange (ETDEWEB)

    Kuebler, R.; Fisch, M.N. [Steinbeis-Transferzentrum Energie-, Gebaeude- und Solartechnik, Stuttgart (Germany)

    1998-12-31

    The aim of this project is the preparation of the ``Large-Scale Solar Heating`` programme for an Europe-wide development of subject technology. The following demonstration programme was judged well by the experts but was not immediately (1996) accepted for financial subsidies. In November 1997 the EU-commission provided 1,5 million ECU which allowed the realisation of an updated project proposal. By mid 1997 a small project was approved, that had been requested under the lead of Chalmes Industriteteknik (CIT) in Sweden and is mainly carried out for the transfer of technology. (orig.) [Deutsch] Ziel dieses Vorhabens ist die Vorbereitung eines Schwerpunktprogramms `Large Scale Solar Heating`, mit dem die Technologie europaweit weiterentwickelt werden sollte. Das daraus entwickelte Demonstrationsprogramm wurde von den Gutachtern positiv bewertet, konnte jedoch nicht auf Anhieb (1996) in die Foerderung aufgenommen werden. Im November 1997 wurden von der EU-Kommission dann kurzfristig noch 1,5 Mio ECU an Foerderung bewilligt, mit denen ein aktualisierter Projektvorschlag realisiert werden kann. Bereits Mitte 1997 wurde ein kleineres Vorhaben bewilligt, das unter Federfuehrung von Chalmers Industriteknik (CIT) in Schweden beantragt worden war und das vor allem dem Technologietransfer dient. (orig.)

  15. Cost Scaling of a Real-World Exhaust Waste Heat Recovery Thermoelectric Generator: A Deeper Dive

    Science.gov (United States)

    Hendricks, Terry J.; Yee, Shannon; LeBlanc, Saniya

    2015-01-01

    Cost is equally important to power density or efficiency for the adoption of waste heat recovery thermoelectric generators (TEG) in many transportation and industrial energy recovery applications. In many cases the system design that minimizes cost (e.g., the $/W value) can be very different than the design that maximizes the system's efficiency or power density, and it is important to understand the relationship between those designs to optimize TEG performance-cost compromises. Expanding on recent cost analysis work and using more detailed system modeling, an enhanced cost scaling analysis of a waste heat recovery thermoelectric generator with more detailed, coupled treatment of the heat exchangers has been performed. In this analysis, the effect of the heat lost to the environment and updated relationships between the hot-side and cold-side conductances that maximize power output are considered. This coupled thermal and thermoelectric treatment of the exhaust waste heat recovery thermoelectric generator yields modified cost scaling and design optimization equations, which are now strongly dependent on the heat leakage fraction, exhaust mass flow rate, and heat exchanger effectiveness. This work shows that heat exchanger costs most often dominate the overall TE system costs, that it is extremely difficult to escape this regime, and in order to achieve TE system costs of $1/W it is necessary to achieve heat exchanger costs of $1/(W/K). Minimum TE system costs per watt generally coincide with maximum power points, but Preferred TE Design Regimes are identified where there is little cost penalty for moving into regions of higher efficiency and slightly lower power outputs. These regimes are closely tied to previously-identified low cost design regimes. This work shows that the optimum fill factor Fopt minimizing system costs decreases as heat losses increase, and increases as exhaust mass flow rate and heat exchanger effectiveness increase. These findings have

  16. Modelling and verification of once-through subcritical heat recovery steam generator

    International Nuclear Information System (INIS)

    Lee, Chae Soo; Choi, Young Jun; Kim, Hyun Gee; Yang, Ok Chul; Chong Chae Hon

    2004-01-01

    The once-through heat recovery steam generator is ideally matched to very high temperature and pressure, well into the supercritical range. Moreover this type of boiler is structurally simpler than drum type boiler. In drum type boiler, each tube play a well-defined role: water preheating, vaporization, superheating. Empirical equations are available to predict the average heat transfer coefficient for each regime. For once-through heat recovery steam generator, this is no more the case and mathematical models have to be adapted to account for the disappearance of drum type economizer, boiler, superheater. General equations have to be used for each tube of boiler, and actual heat transfer condition in each tube has to be identified

  17. Generating acceptability of PNRI environmental radioactivity monitoring studies at the former ammunition dump area in Clark special economic zone

    International Nuclear Information System (INIS)

    Garcia, Teofilo Y.

    2002-11-01

    stakeholders that CSEZ is free of radioactive contamination. The APP principally utilized scientific testing in order to verify the physical presence and extent of radioactive contamination as well as the social marketing approach to generate social acceptability of the scientific findings among the various stakeholders of the base

  18. Generating acceptability of PNRI environmental radioactivity monitoring studies at the former ammunition dump area in Clark special economic zone

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Teofilo Y

    2002-11-01

    stakeholders that CSEZ is free of radioactive contamination. The APP principally utilized scientific testing in order to verify the physical presence and extent of radioactive contamination as well as the social marketing approach to generate social acceptability of the scientific findings among the various stakeholders of the base.

  19. A combined thermal dissociation and electron impact ionization source for radioactive ion beam generation (abstract)a

    International Nuclear Information System (INIS)

    Alton, G.D.; Williams, C.

    1996-01-01

    The probability for simultaneously dissociating and efficiently ionizing the individual atomic constituents of molecular feed materials with conventional, hot-cathode, electron-impact ion sources is low and consequently, the ion beams from these sources often appear as mixtures of several molecular sideband beams. This fragmentation process leads to dilution of the intensity of the species of interest for radioactive ion beam (RIB) applications where beam intensity is at a premium. We have conceived an ion source that combines the excellent molecular dissociation properties of a thermal dissociator and the high ionization efficiency characteristics of an electron impact ionization source that will, in principle, overcome this handicap. The source concept will be evaluated as a potential candidate for use for RIB generation at the Holifield Radioactive Ion Beam Facility, now under construction at the Oak Ridge National Laboratory. The design features and principles of operation of the source are described in this article. copyright 1996 American Institute of Physics

  20. Memory for future generations. To preserve and to transmit the memory of radioactive wastes. Press file - September 2014

    International Nuclear Information System (INIS)

    2014-09-01

    This publication by the ANDRA describes the approach adopted to develop, to preserve and to transmit the memory about radioactive wastes. This approach comprises three components: messages (texts, archives, drawings...), physical supports (paper, disk, markers), and relays (institutions, companies, etc.). The publication describes how these components are already used or implemented for the different radioactive waste storage centres managed by the ANDRA. It also outlines that this memory is an issue of international concern. It evokes issues related to linguistics (how future generations will understand our messages?), to the ageing of materials used as physical support, to archaeology because of the evolution of landscapes, and to the evolution of archival systems. Some simple ideas and projects are briefly indicated which can be a support in memory building

  1. Volume reduction/solidification of liquid radioactive waste using bitumen at Ontario Hydro's Bruce Nuclear Generating Station 'A'

    International Nuclear Information System (INIS)

    Day, J.E.; Baker, R.L.

    1995-01-01

    Ontario Hydro at the Bruce Nuclear Generating Station 'A' has undertaken a program to render the station's liquid radioactive waste suitable for discharge to Lake Huron by removing sufficient radiological and chemical contaminants to satisfy regulatory requirements for emissions. The system will remove radionuclide and chemical contaminants from five different plant waste streams. The contaminants will be immobilized and stored at on-site radioactive waste storage facilities and the purified streams will be discharged. The discharge targets established by Ontario Hydro are set well below the limits established by the Ontario Ministry of Environment (MOE) and are based on the Best Available Technology Economically Achievable Approach (B.A.T.E.A.). ADTECHS Corporation has been selected by Ontario Hydro to provide volume reduction/solidification technology for one of the five waste streams. The system will dry and immobilize the contaminants from a liquid waste stream in emulsified asphalt using thin film evaporation technology

  2. Treatment of Radioactive Waste Generated from the Production of Molybdenum-99 Radioisotope

    International Nuclear Information System (INIS)

    Aisyah; Herlan Martono

    2007-01-01

    The 99 Mo is produced as the parent radionuclide for 99m Tc radioisotope which is used as medical radiodiagnostic for certain disease. In Indonesia 99 Mo is produced by irradiating target of high enriched U in the reactor. The characteristics of radioactive waste from the production of 99 Mo depend on the U enrichment of the target and the irradiation time. The characteristic of the radioactive waste can be directly determined by laboratory analysis or by ORIGEN 2 code. Producing 99 Mo from high enriched uranium target will produce radioactive waste containing 235 U, 238 U and fission product, while from low enriched uranium target will produce radioactive waste containing large amount of 239 Pu. Plutonium-239 is a long half life actinide that need to be separated from the fission product due to a different treatment is required. The fission product, after it is allowed to decay then needs to be categorized as low or medium level waste, while 239 Pu are categorized as transuranic waste. The disposal of low and medium level waste are stored in near surface disposal, while the disposal of transuranic waste is stored in a geologic formation. (author)

  3. Radiological dose assessment related to management of naturally occurring radioactive materials generated by the petroleum industry

    International Nuclear Information System (INIS)

    Smith, K.P.; Blunt, D.L.; Williams, G.P.; Tebes, C.L.

    1995-01-01

    A preliminary radiological dose assessment related to equipment decontamination, subsurface disposal, landspreading, equipment smelting, and equipment burial was conducted to address concerns regarding the presence of naturally occurring radioactive materials in production waste streams. The assessment evaluated the relative dose of these activities and included a sensitivity analysis of certain input parameters. Future studies and potential policy actions are recommended

  4. Numerical analysis for thermal waves in gas generated by impulsive heating of a boundary surface

    International Nuclear Information System (INIS)

    Utsumi, Takayuki; Kunugi, Tomoaki

    1996-01-01

    Thermal wave in gas generated by an impulsive heating of a solid boundary was analyzed numerically by the Differential Algebraic CIP (Cubic Interpolated Propagation) scheme. Numerical results for the ordinary heat conduction equation were obtained with a high accuracy. As for the hyperbolic thermal fluid dynamics equation, the fundamental feature of the experimental results by Brown and Churchill with regard to thermoacoustic convection was qualitatively reproduced by the DA-CIP scheme. (author)

  5. Dense strongly non-ideal plasma generation by laser isobaric heating

    International Nuclear Information System (INIS)

    Kulik, P.P.; Rozanov, E.K.; Riabii, V.A.; Titov, M.A.

    1975-01-01

    A method of generation of a dense strongly non-ideal plasma by slow isobaric heating of a small target in a high inert gas medium is discussed. The characteristic life-time of dense plasma is 10 -3 sec. Estimations show that such a plasma is homogeneous. Conditions are found for temperature uniformity. The experimental results of the isobaric heating of a thin potassium foil target by a ruby laser beam at 500 atm are described. (Auth.)

  6. On the heat exchange tube failures in steam generators at NPPs with WWER reactors

    International Nuclear Information System (INIS)

    Titov, V.F.; Banyuk, G.F.; Brykov, S.I.

    1992-01-01

    Data on dynamics of failed heat exchanging tube closing in steam generators of NPPs with WWER type reactors for the whole period of their operation are presented. It is shown that the main cause of the tube failures consists in their corrosion cracking under stresses. The effect of chlorine ions on tubes is intensified by the presence of porous sediments on heat exchaning surfaces in quantities exceeding 150 g/m 2

  7. Thermal analysis and entropy generation of pulsating heat pipes using nanofluids

    International Nuclear Information System (INIS)

    Jafarmadar, Samad; Azizinia, Nazli; Razmara, Nayyer; Mobadersani, Farrokh

    2016-01-01

    Highlights: • Performance of PHP containing 0.5% Al_2O_3, CuO and silver nanofluids is reported. • The rate of entropy generation of PHP is investigated for different nanofluids. • The effects of particle volume concentration on the entropy generation of PHP are studied. • The appropriate volume concentration for the best thermal efficiency is 0.5–1%. • Al_2O_3 and CuO nanofluids show approximately same rate of entropy generation. - Abstract: Demanding of high-performance cooling systems is one of the most challenging and virtual issues in the industry and pulsating heat pipes (PHPs) are effective solutions for this concern. Nanofluids also have attracted attentions, due to its superior heat transfer properties in recent years. In the present study, the flow, heat transfer and entropy generation based on the second law of thermodynamics have been investigated and compared with the flow of Al_2O_3, CuO, Ag nanofluid and pure water through PHPs. The results show that, silver nanofluid provides the highest entropy generation. Also, the effects of different particle volume concentrations on the heat and flow characteristics of Al_2O_3 nanofluid have been studied. It is indicated that the optimal volume concentration of nanoparticles is about 0.5–1% to minimize the entropy generation and appropriate thermal operation.

  8. Potential ability of zeolite to generate high-temperature vapor using waste heat

    Science.gov (United States)

    Fukai, Jun; Wijayanta, Agung Tri

    2018-02-01

    In various material product industries, a large amount of high temperature steam as heat sources are produced from fossil fuel, then thermal energy retained by condensed water at lower than 100°C are wasted. Thermal energies retained by exhaust gases at lower than 200°C are also wasted. Effective utilization of waste heat is believed to be one of important issues to solve global problems of energy and environment. Zeolite/water adsorption systems are introduced to recover such low-temperature waste heats in this study. Firstly, an adsorption steam recovery system was developed to generate high temperature steam from unused hot waste heat. The system used a new principle that adsorption heat of zeolite/water contact was efficiently extracted. A bench-scaled system was constructed, demonstrating contentious generation of saturated steam nearly 150°C from hot water at 80°C. Energy conservation is expected by returning the generated steam to steam lines in the product processes. Secondly, it was demonstrated that superheated steam/vapor at higher than 200°C could be generated from those at nearly 120°C using a laboratory-scaled setup. The maximum temperature and the time variation of output temperature were successfully estimated using macroscopic heat balances. Lastly, the maximum temperatures were estimated whose saturate air at the relative humidity 20-80% were heated by the present system. Theoretically, air at higher than 200°C was generated from saturate air at higher than 70°C. Consequently, zeolite/water adsorption systems have potential ability to regenerate thermal energy of waste water and exhaust gases.

  9. Entropy generation in natural convection in a symmetrically and uniformly heated vertical channel

    Energy Technology Data Exchange (ETDEWEB)

    Andreozzi, Assunta [Dipartimento di Energetica, Termofluidodinamica applicata e Condizionamenti ambientali, Universita degli Studi di Napoli Federico II, Piazzale Tecchio 80, 80125 Napoli (Italy); Auletta, Antonio [CIRA - Centro Italiano Ricerche Aerospaziali, Via Maiorise 1, 81043 Capua (CE) (Italy); Manca, Oronzio [Dipartimento di Ingegneria Aerospaziale e Meccanica, Seconda Universita degli Studi di Napoli, Real Casa dell' Annunziata, Via Roma 29, 81031 Aversa (CE) (Italy)

    2006-08-15

    In this study numerical predictions of local and global entropy generation rates in natural convection in air in a vertical channel symmetrically heated at uniform heat flux are reported. Results of entropy generation analysis are obtained by solving the entropy generation equation based on the velocity and temperature data. The analyzed regime is two-dimensional, laminar and steady state. The numerical procedure expands an existing computer code on natural convection in vertical channels. Results in terms of fields and profiles of local entropy generation, for various Rayleigh number, Ra, and aspect ratio values, L/b, are given. The distributions of local values show different behaviours for the different Ra values. A correlation between global entropy generation rates, Rayleigh number and aspect ratio is proposed in the ranges 10{sup 3}=

  10. Efficient heat generation in large-area graphene films by electromagnetic wave absorption

    Science.gov (United States)

    Kang, Sangmin; Choi, Haehyun; Lee, Soo Bin; Park, Seong Chae; Park, Jong Bo; Lee, Sangkyu; Kim, Youngsoo; Hong, Byung Hee

    2017-06-01

    Graphene has been intensively studied due to its outstanding electrical and thermal properties. Recently, it was found that the heat generation by Joule heating of graphene is limited by the conductivity of graphene. Here we suggest an alternative method to generate heat on a large-area graphene film more efficiently by utilizing the unique electromagnetic (EM) wave absorption property of graphene. The EM wave induces an oscillating magnetic moment generated by the orbital motion of moving electrons, which efficiently absorbs the EM energy and dissipate it as a thermal energy. In this case, the mobility of electron is more important than the conductivity, because the EM-induced diamagnetic moment is directly proportional to the speed of electron in an orbital motion. To control the charge carrier mobility of graphene we functionalized substrates with self-assembled monolayers (SAM). As the result, we find that the graphene showing the Dirac voltage close to zero can be more efficiently heated by EM waves. In addition, the temperature gradient also depends on the number of graphene. We expect that the efficient and fast heating of graphene films by EM waves can be utilized for smart heating windows and defogging windshields.

  11. A thermoelectric power generating heat exchanger: Part II – Numerical modeling and optimization

    DEFF Research Database (Denmark)

    Sarhadi, Ali; Bjørk, Rasmus; Lindeburg, N.

    2016-01-01

    In Part I of this study, the performance of an experimental integrated thermoelectric generator (TEG)-heat exchanger was presented. In the current study, Part II, the obtained experimental results are compared with those predicted by a finite element (FE) model. In the simulation of the integrated...... TEG-heat exchanger, the thermal contact resistance between the TEG and the heat exchanger is modeled assuming either an ideal thermal contact or using a combined Cooper–Mikic–Yovanovich (CMY) and parallel plate gap formulation, which takes into account the contact pressure, roughness and hardness...

  12. Temperature anisotropy in a cyclotron resonance heated tokamak plasma and the generation of poloidal electric field

    International Nuclear Information System (INIS)

    Choe, W.; Ono, M.; Chang, C.S.

    1994-11-01

    The temperature anisotropy generated by cyclotron resonance heating of tokamak plasmas is calculated and the poloidal equilibrium electric field due to the anisotropy is studied. For the calculation of anisotropic temperatures, bounce-averaged Fokker-Planck equation with a bi-Maxwellian distribution function of heated particles is solved, assuming a moderate wave power and a constant quasilinear cyclotron resonance diffusion coefficient. The poloidal electrostatic potential variation is found to be proportional to the particle density and the degree of temperature anisotropy of warm species created by cyclotron resonance heating

  13. Effect of Heat Generation of Ultrasound Transducer on Ultrasonic Power Measured by Calorimetric Method

    Science.gov (United States)

    Uchida, Takeyoshi; Kikuchi, Tsuneo

    2013-07-01

    Ultrasonic power is one of the key quantities closely related to the safety of medical ultrasonic equipment. An ultrasonic power standard is required for establishment of safety. Generally, an ultrasonic power standard below approximately 20 W is established by the radiation force balance (RFB) method as the most accurate measurement method. However, RFB is not suitable for high ultrasonic power because of thermal damage to the absorbing target. Consequently, an alternative method to RFB is required. We have been developing a measurement technique for high ultrasonic power by the calorimetric method. In this study, we examined the effect of heat generation of an ultrasound transducer on ultrasonic power measured by the calorimetric method. As a result, an excessively high ultrasonic power was measured owing to the effect of heat generation from internal loss in the transducer. A reference ultrasound transducer with low heat generation is required for a high ultrasonic power standard established by the calorimetric method.

  14. Random generation of bubble sizes on the heated wall during subcooled boiling

    International Nuclear Information System (INIS)

    Koncar, B.; Mavko, B.

    2003-01-01

    In subcooled flow boiling, a locally averaged bubble diameter significantly varies in the transverse direction to the flow. From the experimental data of Bartel, a bent crosssectional profile of local bubble diameter with the maximum value shifted away from the heated wall may be observed. In the present paper, the increasing part of the profile (near the heated wall) is explained by a random generation of bubble sizes on the heated wall. The hypothesis was supported by a statistical analysis of different CFD simulations, varying by the size of the generated bubble (normal distribution) and the number of generated bubbles per unit surface. Local averaging of calculated void fraction distributions over different bubble classes was performed. The increasing curve of the locally averaged bubble diameter in the near-wall region was successfully predicted. (author)

  15. A review on heat sink for thermo-electric power generation: Classifications and parameters affecting performance

    International Nuclear Information System (INIS)

    Elghool, Ali; Basrawi, Firdaus; Ibrahim, Thamir Khalil; Habib, Khairul; Ibrahim, Hassan; Idris, Daing Mohamad Nafiz Daing

    2017-01-01

    Highlights: • Coupling a thermoelectric power generation (TEG) to a heat sink is presented. • Review the classifications and parameters affecting performance of the TEG with heat sink. • Discuss different mathematical models of the heat sinks. • The passive heat sinks are most appropriate because of the inherent efficiency of TEG. • Medium temperature range below 300 °C is found to be most suitable for HPHS. - Abstract: In recent years, there have been growing interests in key areas related to global warming resulting from environmental emissions, and the diminishing sources of fossil fuel. The increased interest has led to significant research efforts towards finding novel technologies in clean energy production. Consequently, the merits of a thermo-electric generator (TEG) have promised a revival of alternative means of producing green energy. It is, however, impractical to account for the cost of thermal energy input to the TEG which is in the form of final waste heat. This is because the technology presents critical limitations in determining its cost efficiency nor its economic disadvantages. This paper reviews the principles of thermo-electric power production, as well the materials use, performance achieved, and application areas. The paper also takes a particular deliberation on TEG heat sinks geometries and categories. The review emphasizes more on the TEG performance while considering a number of heat sink parameters related to its performance.

  16. Thermoelectric Generators for Automotive Waste Heat Recovery Systems Part I: Numerical Modeling and Baseline Model Analysis

    Science.gov (United States)

    Kumar, Sumeet; Heister, Stephen D.; Xu, Xianfan; Salvador, James R.; Meisner, Gregory P.

    2013-04-01

    A numerical model has been developed to simulate coupled thermal and electrical energy transfer processes in a thermoelectric generator (TEG) designed for automotive waste heat recovery systems. This model is capable of computing the overall heat transferred, the electrical power output, and the associated pressure drop for given inlet conditions of the exhaust gas and the available TEG volume. Multiple-filled skutterudites and conventional bismuth telluride are considered for thermoelectric modules (TEMs) for conversion of waste heat from exhaust into usable electrical power. Heat transfer between the hot exhaust gas and the hot side of the TEMs is enhanced with the use of a plate-fin heat exchanger integrated within the TEG and using liquid coolant on the cold side. The TEG is discretized along the exhaust flow direction using a finite-volume method. Each control volume is modeled as a thermal resistance network which consists of integrated submodels including a heat exchanger and a thermoelectric device. The pressure drop along the TEG is calculated using standard pressure loss correlations and viscous drag models. The model is validated to preserve global energy balances and is applied to analyze a prototype TEG with data provided by General Motors. Detailed results are provided for local and global heat transfer and electric power generation. In the companion paper, the model is then applied to consider various TEG topologies using skutterudite and bismuth telluride TEMs.

  17. Heat transfer characteristics of horizontal steam generators under natural circulation conditions

    International Nuclear Information System (INIS)

    Hyvaerinen, J.

    1996-01-01

    This paper deals with the heat transfer characteristics of horizontal steam generators, particularly under natural circulation (decay heat removal) conditions on the primary side. Special emphasis is on the inherent features of horizontal steam generator behaviour. A mathematical model of the horizontal steam generator primary side is developed and qualitative results are obtained analytically. A computer code, called HSG, is developed to solve the model numerically, and its predictions are compared with experimental data. The code is employed to obtain for VVER 440 steam generators quantitative results concerning the dependence of primary-to-secondary heat transfer efficiency on the primary side flow rate, temperature and secondary level. It turns out that the depletion of the secondary inventory leads to an inherent limitation of the decay energy removal in VVER steam generators. The limitation arises as a consequence of the steam generator tube bundle geometry. As an example, it is shown that the grace period associated with pressurizer safety valve opening during a station black-out is 2 1/2-3 hours instead of the 5-6 hours reported in several earlier studies. (However, the change in core heat-up timing is much less-about 1 h at most.) The heat transfer limitation explains the fact that, in the Greifswald VVER 440 station black-out accident in 1975, the steam generators never boiled dry. In addition, the stability of single-phase natural circulation is discussed and insights on the modelling of horizontal steam generators with general-purpose thermal-hydraulic system codes are also presented. (orig.)

  18. Next-generation heat pump systems in residential buildings and commercial premises; Naesta generations vaermepumpssystem i bostaeder och lokaler

    Energy Technology Data Exchange (ETDEWEB)

    Haglund Stignor, Caroline; Lindahl, Markus; Alsbjer, Markus; Nordman, Roger; Rolfsman, Lennart; Axell, Monica

    2009-07-01

    Summarising, the following conclusions can be drawn from this work. - Installation of a heat pump system is a very efficient way of reducing a building's energy demand without making any greater changes to the building's climate screen, and can therefore assist Sweden's achievement of its energy efficiency improvement targets. - A new generation of cost-effective smaller heat pumps is needed for installation in new detached houses or those being renovated and upgraded. - There also seems to be an excellent market potential for heat pumps that are larger than has previously been common: there should be good prospects for selling them for use in apartment buildings and in commercial or similar premises. - Heat pump installations are particularly competitive in applications where there are simultaneous heating and cooling demands in the property, and also in those cases where heating is required for most of the year and cooling for some other part of the year. If these suggested system arrangements are to be fully realised, there will be a need for further research in certain cases. Particularly, there is a need for research and development of more efficient pumps, fans and speed-controlled compressors in order to get such products on to the market. Performance measurements and follow-up of real systems are needed in order to obtain a clear picture of the efficiency of both present-day and proposed systems. This knowledge is essential for further development of systems, not only for residential buildings but also, even more importantly, for commercial and similar premises. Actual heating and cooling requirements in different types of non-residential premises need to be known more accurately in order to decide how systems should be controlled in order to minimise total energy use. Much indicates that future detached houses will be more energy-efficient, which could have the undesirable result of greater use of direct electric heating, as the investment

  19. 3D-nuclear heat generation in PCC-charcoal filter in TAPP-3 and 4

    International Nuclear Information System (INIS)

    Kaushal, Manish; Pradhan, A.S.; Kumar, A.N.

    2006-01-01

    This paper deals with the calculations of 3D nuclear heat generation profile in the charcoal filter and subsequently the commencement time of Primary Containment Cleanup (PCC) system of 540MWe Pressurized Heavy Water Reactor (PHWR). Fuel failure is predicted due to overheating of the fuel under loss of Coolant Accident (LOCA) without Emergency Core Cooling System (LOCA without ECCS). Subsequently fission product gasses along with water vapours are released to Reactor Building (RB) atmosphere. Plate-out and water trapping mechanism stabilizes the concentration of significant fission products i.e. radioiodines in about 4 hours before being circulated through charcoal filters of Containment Cleanup system. After cleaning up the RB atmosphere, it is discharged to outside atmosphere through stack. The isotopes of radioiodine emit beta and gamma radiations. Gamma radiations are partly stopped within the charcoal and heat is generated. The part of gamma radiations escaping the bed produce heat in the adjacent beds also. PCC system can be operated, after 4 hours of LOCA, based on radioiodine concentration in RB atmosphere. During iodine removal, the iodine concentration in the charcoal filter goes through a peak value. Maximum heat is generated in the filter if PCC fans stops eventually when iodine concentration in the filter is maximum. Analysis done by TRAFIC code indicates that the system can be commenced after 7 hrs of LOCA so that desorption temperature of charcoal is not reached. Accuracy in estimating heat generation rates in charcoal helps in deciding commencement of the system after LOCA

  20. D'' Layer Activation via Tidal Dissipation: A Link Between Non-Hydrostatic Ellipticity, Non-Chondritic Heat Flux, and Non-Plume Head Generation of Flood Basalts

    Science.gov (United States)

    Hager, B. H.; Mazarico, E.; Touma, J.; Wisdom, J.

    2003-12-01

    Quantitative understanding of Earth's heat budget has eluded a list of distinguished physicists and geochemists ranging from Lord Kelvin to Don L Anderson. The global heat flux is substantially greater than that generated by the estimated inventory of radioactive heat sources, so simple energy balance considerations demand an additional heat source. Secular cooling is commonly invoked to balance Earth's energy budget, but the required cooling rates are difficult to reconcile with both traditional convection calculations and petrologic estimates of ancient upper mantle temperatures. A non-geochemical heat source seems plausible. Indeed, Tuoma and Wisdom (Astron. J., 122, 2001) showed that tidal dissipation of rotational energy associated with resonant coupling could provide a substantial heat pulse to the CMB. D'' Layer Activation (DLA) by dumping of rotational energy could have important geodynamical consequences that we explore here. DLA could lead to a sudden (but modest) increase in the temperature of preexisting plumes, leading to a sudden increase in melt volume without the need for a troublesome plume head. The dissipation depends on non-hydrostatic CMB ellipticity, which itself is a result of mantle convection, leading to the possibility of an important feedback mechanism - DLA would lead to an increase in CMB ellipticity, further increasing the geodynamic importance of DLA.

  1. Diagnostic system of steam generator, especially molten metal heated steam generator

    International Nuclear Information System (INIS)

    Matal, O.; Martoch, J.

    1986-01-01

    A diagnostic system is described and graphically represented consisting of a leak detector, a medium analyzer and sensors placed on the piping connected to the indication sections of both tube plates. The advantage of the designed system consists in the possibility of detecting tube failure immediately on leak formation, especially in generators with duplex tubes. This shortens the period of steam generator shutdown for repair and reduces power losses. The design also allows to make periodical leak tests during planned steam generator shutdowns. (A.K.)

  2. Characteristics of entropy generation and heat transfer in double-layered micro heat sinks with complex structure

    International Nuclear Information System (INIS)

    Zhai, Y.L.; Xia, G.D.; Liu, X.F.; Wang, J.

    2015-01-01

    Highlights: • A novel DL-MCHS with complex structure is presented. • A model of entropy generation rate of DL-MCHSs is derived from the first and second laws of thermodynamics. • DL-MCHSs show better thermodynamic advantage and thermal performance under large volumetric flow rate. - Abstract: A new type of double-layered micro heat sink (DL-MCHS) with complex structure is designed and investigated numerically. Moreover, a model of entropy generation rate of DL-MCHSs is also derived from the first and second laws of thermodynamics. Results for the relationship of entropy generation rate between the first and second layer of DL-MCHSs, total entropy generation rate, the average temperature on the bottom wall, thermal resistance and pressure drop are investigated in detail, respectively. The results indicate that the effect of entropy generation rate of the first layer on total entropy generation rate is dominant. The thermal characteristic of DL-MCHSs with complex structure is better than that of all DL-MCHSs and single-layered micro heat sinks (SL-MCHSs) with simple structure under the same volumetric flow rate. However, DL-MCHSs only show better thermodynamic advantage and thermal performance than SL-MCHSs with complex structure when the volumetric flow rate larger than a certain value. It is not reasonable to use DL-MCHSs for cooling microelectronic equipments under small volumetric flow rate due to the larger irreversibility. Finally, the pressure drop of DL-MHCSs can be reduced by properly changing the channel height under various volumetric flow rates. Due to the less irreversibility and more uniform temperature distribution on the bottom wall, DL-MCHSs can effectively eliminate the internal thermal stresses in microelectronic equipments. Therefore, DL-MCHSs are an alternative method for the electronic cooling. Moreover, the thermodynamic analysis provides references for the actual application design

  3. Multi-boiling Heat Transfer Analysis of a Convective Straight Fin with Temperature-Dependent Thermal Properties and Internal Heat Generation

    Directory of Open Access Journals (Sweden)

    Gbeminiyi Sobamowo

    2017-10-01

    Full Text Available In this study, by using the finite volume method, the heat transfer in a convective straight fin with temperature-dependent thermal properties and an internal heat generation under multi-boiling heat transfer modes are analyzed. In this regard, the local heat transfer coefficient is considered to vary within a power-law function of temperature. In the present study, the coexistence of all the boiling modes is taken into consideration. The developed heat transfer models and the corresponding numerical solutions are used to investigate the effects of various thermo-geometric parameters on the thermal performance of the longitudinal rectangular fin. The results shows that the fin temperature distribution, the total heat transfer, and the fin efficiency are significantly affected by the thermo-geometric parameters of the fin and the internal heat generation within the fin. The obtained results can provide a platform for improvements in the design of the fin in the heat transfer equipment.

  4. Experimental investigation of thermoelectric power generation versus coolant pumping power in a microchannel heat sink

    DEFF Research Database (Denmark)

    Kolaei, Alireza Rezania; Rosendahl, Lasse; Andreasen, Søren Juhl

    2012-01-01

    The coolant heat sinks in thermoelectric generators (TEG) play an important role in order to power generation in the energy systems. This paper explores the effective pumping power required for the TEGs cooling at five temperature difference of the hot and cold sides of the TEG. In addition......, the temperature distribution and the pressure drop in sample microchannels are considered at four sample coolant flow rates. The heat sink contains twenty plate-fin microchannels with hydraulic diameter equal to 0.93 mm. The experimental results show that there is a unique flow rate that gives maximum net-power...

  5. Steam generators and waste heat boilers for process and plant engineers

    CERN Document Server

    Ganapathy, V

    2014-01-01

    Incorporates Worked-Out Real-World ProblemsSteam Generators and Waste Heat Boilers: For Process and Plant Engineers focuses on the thermal design and performance aspects of steam generators, HRSGs and fire tube, water tube waste heat boilers including air heaters, and condensing economizers. Over 120 real-life problems are fully worked out which will help plant engineers in evaluating new boilers or making modifications to existing boiler components without assistance from boiler suppliers. The book examines recent trends and developments in boiler design and technology and presents novel idea

  6. Waste heat recovery from the exhaust of a diesel generator using Rankine Cycle

    International Nuclear Information System (INIS)

    Hossain, Shekh Nisar; Bari, Saiful

    2013-01-01

    Highlights: • Diesel engine exhaust contains 40% energy which can be used to produce extra power. • Extra 11% power gained with optimized heat exchangers using water as working fluid. • As a result brake specific fuel consumption improved by 12%. • Parallel arrangement of heat exchangers showed better performance than series. • Optimum working fluid pressure varies with the engine power. - Abstract: Exhaust heat from diesel engines can be an important heat source to provide additional power using a separate Rankine Cycle (RC). In this research, experiments were conducted to measure the available exhaust heat from a 40 kW diesel generator using two ‘off-the-shelf’ heat exchangers. The effectiveness of the heat exchangers using water as the working fluid was found to be 0.44 which seems to be lower than a standard one. This lower performance of the existing heat exchangers indicates the necessity of optimization of the design of the heat exchangers for this particular application. With the available experimental data, computer simulations were carried out to optimize the design of the heat exchangers. Two heat exchangers were used to generate super-heated steam to expand in the turbine using two orientations: series and parallel. The optimized heat exchangers were then used to estimate additional power considering actual turbine isentropic efficiency. The proposed heat exchanger was able to produce 11% additional power using water as the working fluid at a pressure of 15 bar at rated engine load. This additional power resulted into 12% improvement in brake-specific fuel consumption (bsfc). The effects of the working fluid pressure were also investigated to maximize the additional power production. The pressure was limited to 15 bar which was constrained by the exhaust gas temperature. However, higher pressure is possible for higher exhaust gas temperatures from higher capacity engines. This would yield more additional power with further improvements in

  7. Heat transfer enhancement of a modularised thermoelectric power generator for passenger vehicles

    International Nuclear Information System (INIS)

    Li, Bo; Huang, Kuo; Yan, Yuying; Li, Yong; Twaha, Ssennoga; Zhu, Jie

    2017-01-01

    Highlights: •Shape-adapted thermoelectric module for highly compact heat recovery exchanger assembly. •Heat pipe-assisted heat transfer enhancement method for better power output. •Highest power output ratio to the total volume of heat recovery exchanger. •Cascaded thermoelectric system can be scaled and extended for various power output. •Self-clamping design of thermoelectric module can solve the thermomechanical imbalances. -- Abstract: Transport represents over a quarter of Europe's greenhouse gas emissions and is the leading cause of air pollution in cities. It has not seen the same gradual decline in emissions as other sectors. Recently, the thermoelectric power generation (TEG) technology emerges as an alternative solution to the emission reduction challenge in this area. In this paper, we present an innovative pathway to an improved heat supply into the concentric shape-adapted TEG modules, integrating the heat pipe technologies. It relies on a phase changing approach which enhances the heat flux through the TEG surface. In order to improve the heat transfer for higher efficiency, in our work, the heat pipes are configured in the radial direction of the exhaust streams. The analysis shows that the power output is adequate for the limited space under the chassis of the passenger car. Much effort can also be applied to obtain enhanced convective heat transfer by adjusting the heat pipes at the dual sides of the concentric TEG modules. Heat enhancement at the hot side of the TEG has an effective impact on the total power out of the TEG modules. However, such improvements can be offset by the adjustment made from the coolant side. Predictably, the whole temperature profile of TEG system is subject to the durability and operational limitations of each component. Furthermore, the results highlight the importance of heat transfer versus the TEG power generation under two possible configurations in the passenger car. The highest power output per

  8. Radioactive materials

    International Nuclear Information System (INIS)

    Sugiura, Yoshio; Shimizu, Makoto.

    1975-01-01

    The problems of radioactivity in the ocean with marine life are various. Activities in this field, especially the measurements of the radioactivity in sea water and marine life are described. The works first started in Japan concerning nuclear weapon tests. Then the port call to Japan by U.S. nuclear-powered naval ships began. On the other hand, nuclear power generation is advancing with its discharge of warm water. The radioactive pollution of sea water, and hence the contamination of marine life are now major problems. Surveys of the sea areas concerned and study of the radioactivity intake by fishes and others are carried out extensively in Japan. (Mori, K.)

  9. Effect of constant and uniform heat generation on the thermal behaviour of porous solids with asymmetric boundary conditions

    International Nuclear Information System (INIS)

    Heggs, P.J.; Dare, J.

    2007-01-01

    The generation of heat due to chemical reaction will have a significant effect on the temperature profile and heat transfer within a porous body. Most forms of analysis only consider the symmetric situation or else make use of various assumptions that greatly simplify the analysis, for example: the Semenov or the Frak-kamenetskii models. The objective of this paper is to develop an improved understanding of the thermal behaviour of a porous body with uniform internal heat generation, which is in contact with two fluids at different temperatures and with different heat transfer coefficients. The mathematical representation is a one dimensional Poisson equation with asymmetric boundary conditions. The analytical solution reveals four regimes for heat flow: (a) purely conduction at zero heat generation, (b) a combination of heat flow by conduction through the body between the hot and cold fluids and all heat generated passing to the colder fluid, (c) no heat flow by conduction between the two fluids and all heat generated passing the cold flow - the so-called critical heat generation, and (d) the heat generated passes to both the cold and hot fluids and there is a maximum temperature within the body greater than that of the hot fluid, the so-called supercritical region. Expressions are developed to allow predictions of the conditions pertaining to each regime. This new representation covers the Semenov and Frank-Kamenetskii models and all possible solutions intermediate of the them. (authors)

  10. Simulation and Optimization of the Heat Exchanger for Automotive Exhaust-Based Thermoelectric Generators

    Science.gov (United States)

    Su, C. Q.; Huang, C.; Deng, Y. D.; Wang, Y. P.; Chu, P. Q.; Zheng, S. J.

    2016-03-01

    In order to enhance the exhaust waste heat recovery efficiency of the automotive exhaust-based thermoelectric generator (TEG) system, a three-segment heat exchanger with folded-shaped internal structure for the TEG system is investigated in this study. As the major effect factors of the performance for the TEG system, surface temperature, and thermal uniformity of the heat exchanger are analyzed in this research, pressure drop along the heat exchanger is also considered. Based on computational fluid dynamics simulations and temperature distribution, the pressure drop along the heat exchanger is obtained. By considering variable length and thickness of folded plates in each segment of the heat exchanger, response surface methodology and optimization by a multi-objective genetic algorithm is applied for surface temperature, thermal uniformity, and pressure drop for the folded-shaped heat exchanger. An optimum design based on the optimization is proposed to improve the overall performance of the TEG system. The performance of the optimized heat exchanger in different engine conditions is discussed.

  11. Hydrous mineral dehydration around heat-generating nuclear waste in bedded salt formations.

    Science.gov (United States)

    Jordan, Amy B; Boukhalfa, Hakim; Caporuscio, Florie A; Robinson, Bruce A; Stauffer, Philip H

    2015-06-02

    Heat-generating nuclear waste disposal in bedded salt during the first two years after waste emplacement is explored using numerical simulations tied to experiments of hydrous mineral dehydration. Heating impure salt samples to temperatures of 265 °C can release over 20% by mass of hydrous minerals as water. Three steps in a series of dehydration reactions are measured (65, 110, and 265 °C), and water loss associated with each step is averaged from experimental data into a water source model. Simulations using this dehydration model are used to predict temperature, moisture, and porosity after heating by 750-W waste canisters, assuming hydrous mineral mass fractions from 0 to 10%. The formation of a three-phase heat pipe (with counter-circulation of vapor and brine) occurs as water vapor is driven away from the heat source, condenses, and flows back toward the heat source, leading to changes in porosity, permeability, temperature, saturation, and thermal conductivity of the backfill salt surrounding the waste canisters. Heat pipe formation depends on temperature, moisture availability, and mobility. In certain cases, dehydration of hydrous minerals provides sufficient extra moisture to push the system into a sustained heat pipe, where simulations neglecting this process do not.

  12. Numerical and experimental analysis for exhaust heat exchangers in automobile thermoelectric generators

    Directory of Open Access Journals (Sweden)

    Shengqiang Bai

    2014-11-01

    Full Text Available Ideal heat exchangers recover as much heat as possible from an engine exhaust at the cost of an acceptable pressure drop. They provide primary heat for a thermoelectric generator (TEG, and their capacity and efficiency is dependent on the material, shape, and type of the heat exchanger. Six different exhaust heat exchangers were designed within the same shell, and their computational fluid dynamics (CFD models were developed to compare heat transfer and pressure drop in typical driving cycles for a vehicle with a 1.2 L gasoline engine. The result showed that the serial plate structure enhanced heat transfer by 7 baffles and transferred the maximum heat of 1737 W. It also produced a maximum pressure drop of 9.7 kPa in a suburban driving cycle. The numerical results for the pipe structure and an empty cavity were verified by experiments. Under the maximum power output condition, only the inclined plate and empty cavity structure undergoes a pressure drop less than 80 kPa, and the largest pressure drop exceeds 190 kPa. In this case, a mechanism with a differential pressure switch is essential to bypass part of the exhaust.

  13. Effect of heat transfer tube leak on dynamic characteristic of steam generator

    International Nuclear Information System (INIS)

    Sun Baozhi; Shi Jianxin; Li Na; Zheng Lusong; Liu Shanghua; Lei Yu

    2015-01-01

    Taking the steam generator of Daya Bay Nuclear Power Station as the research object, one-dimensional dynamic model of the steam generator based on drift flux theory and leak model of heat transfer tube were established. Steady simulation of steam generator under different conditions was carried out. Based on verifying the drift flux model and leak model of heat transfer tube, the effect of leak location and flow rate under different conditions on steam generator's key parameters was studied. The results show that the drift flux model and leak model can reflect the law of key parameter change accurately such as vapor mass fraction and steam pressure under different leak cases. The variation of the parameters is most apparent when the leak is at the entrance of boiling section and vapor mass fraction varies from 0.261 to 0.163 when leakage accounts for 5% of coolant flow rate. The successful prediction of the effect of heat transfer tube leak on dynamic characteristics of the steam generator based on drift flux theory supplies some references for monitoring and taking precautionary measures to prevent heat transfer tube leak accident. (authors)

  14. Condition monitoring of steam generator by estimating the overall heat transfer coefficient

    International Nuclear Information System (INIS)

    Furusawa, Hiroaki; Gofuku, Akio

    2013-01-01

    This study develops a technique for monitoring in on-line the state of the steam generator of the fast-breeder reactor (FBR) “Monju”. Because the FBR uses liquid sodium as coolant, it is necessary to handle liquid sodium with caution due to its chemical characteristics. The steam generator generates steam by the heat of secondary sodium coolant. The sodium-water reaction may happen if a pinhole or crack occurs at the thin metal tube wall that separates the secondary sodium coolant and water/steam. Therefore, it is very important to detect an anomaly of the wall of heat transfer tubes at an early stage. This study aims at developing an on-line condition monitoring technique of the steam generator by estimating overall heat transfer coefficient from process signals. This paper describes simplified mathematical models of superheater and evaporator to estimate the overall heat transfer coefficient and a technique to diagnose the state of the steam generator. The applicability of the technique is confirmed by several estimations using simulated process signals with artificial noises. The results of the estimations show that the developed technique can detect the occurrence of an anomaly. (author)

  15. Estimation of the heat generation in vitrified waste product and shield thickness of the cask for the transportation of vitrified waste product using Monte Carlo technique

    International Nuclear Information System (INIS)

    Deepa, A.K.; Jakhete, A.P.; Mehta, D.; Kaushik, C.P.

    2011-01-01

    High Level Liquid waste (HLW) generated during reprocessing of spent fuel contains most of the radioactivity present in the spent fuel resulting in the need for isolation and surveillance for extended period of time. Major components in HLW are the corrosion products, fission products such as 137 Cs, 90 Sr, 106 Ru, 144 Ce, 125 Sb etc, actinides and various chemicals used during reprocessing of spent fuel. Fresh HLW having an activity concentration of around 100Ci/l is to be vitrified into borosilicate glass and packed in canisters which are placed in S.S overpacks for better confinement. These overpacks contain around 0.7 Million Curies of activity. Characterisation of activity in HLW and activity profile of radionuclides for various cooling periods sets the base for the study. For transporting the vitrified waste product (VWP), two most important parameters is the shield thickness of the transportation cask and the heat generation in the waste product. This paper describes the methodology used in the estimation of lead thickness for the transportation cask using the Monte Carlo Technique. Heat generation due to decay of fission products results in the increase in temperature of the vitrified waste product during interim storage and disposal. Glass being the material, not having very high thermal conductivity, temperature difference between the canister and surrounding bears significance in view of the possibility of temperature based devitrification of VWP. The heat generation in the canister and the overpack containing vitrified glass is also estimated using MCNP. (author)

  16. Radioactive waste in Federal Germany

    International Nuclear Information System (INIS)

    Brennecke, P.; Schumacher, J.; Warnecke, E.

    1988-01-01

    The Physikalisch-Technische Bundesanstalt (PTB) is responsible for the long-term storage and disposal of radioactive waste according to the Federal Atomic Energy Act. On behalf of the Federal Minister of the Environment, Nature Conservation and Nuclear Safety, since 1985, the PTB has been carrying out annual inquiries into the amounts of radioactive waste produced in the Federal Republic of Germany. Within the scope of this inquiry performed for the preceding year, the amounts of unconditioned and conditioned waste are compiled on a producer- and plant-specific basis. On the basis of the inquiry for 1986 and of data presented to the PTB by the waste producers, future amounts of radioactive waste have been estimated up to the year 2000. The result of this forecast is presented. In the Federal Republic of Germany two sites are under consideration for disposal of radioactive waste. In the abandoned Konrad iron mine in Salzgitter-Bleckenstedt it is intended to dispose of such radioactive waste which has a negligible thermal influence upon the host rock. The Gorleben salt dome is being investigated for its suitability for the disposal of all kinds of solid and solidified radioactive wastes, especially of heat-generating waste. Comparing the estimated amount of radioactive wastes with the capacity of both repositories it may be concluded that the Konrad and Gorleben repositories will provide sufficient capacity to ensure the disposal of all kinds of radioactive waste on a long-term basis in the Federal Republic of Germany. 1 fig., 2 tabs

  17. Proceedings of the third international steam generator and heat exchanger conference

    International Nuclear Information System (INIS)

    1998-01-01

    The Third International Steam Generator and Heat Exchanger conference had the objective to present the state of knowledge of steam generator performance and life management, and also heat exchanger technology. As this conference followed on from the previous conferences held in Toronto in 1990 and 1994, the emphasis was on recent developments, particularly those of the last 4 years. The conference provided an opportunity to operators, designers and researchers in the field of steam generation associated with electricity generation by nuclear energy to present their findings and exchange ideas. The conference endeavoured to do this over the widest possible range of subject areas, including: general operating experience, life management and fitness for service strategies, maintenance and inspection, thermalhydraulics, vibration, fretting and fatigue, materials, chemistry and corrosion and the regulatory issues

  18. Proceedings of the third international steam generator and heat exchanger conference

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    The Third International Steam Generator and Heat Exchanger conference had the objective to present the state of knowledge of steam generator performance and life management, and also heat exchanger technology. As this conference followed on from the previous conferences held in Toronto in 1990 and 1994, the emphasis was on recent developments, particularly those of the last 4 years. The conference provided an opportunity to operators, designers and researchers in the field of steam generation associated with electricity generation by nuclear energy to present their findings and exchange ideas. The conference endeavoured to do this over the widest possible range of subject areas,including: general operating experience, life management and fitness for service strategies, maintenance and inspection, thermalhydraulics, vibration, fretting and fatigue, materials, chemistry and corrosion and the regulatory issues.

  19. Thermoelectric Power Generation Utilizing the Waste Heat from a Biomass Boiler

    Science.gov (United States)

    Brazdil, Marian; Pospisil, Jiri

    2013-07-01

    The objective of the presented work is to test the possibility of using thermoelectric power to convert flue gas waste heat from a small-scale domestic pellet boiler, and to assess the influence of a thermoelectric generator on its function. A prototype of the generator, able to be connected to an existing device, was designed, constructed, and tested. The performance of the generator as well as the impact of the generator on the operation of the boiler was investigated under various operating conditions. The boiler gained auxiliary power and could become a combined heat and power unit allowing self-sufficient operation. The created unit represents an independent source of electricity with effective use of fuel.

  20. Nanophotonic-Engineered Photothermal Harnessing for Waste Heat Management and Pyroelectric Generation.

    Science.gov (United States)

    Wang, Xiao-Qiao; Tan, Chuan Fu; Chan, Kwok Hoe; Xu, Kaichen; Hong, Minghui; Kim, Sang-Woo; Ho, Ghim Wei

    2017-10-24

    At present, there are various limitations to harvesting ambient waste heat which include the lack of economically viable material and innovative design features that can efficiently recover low grade heat for useful energy conversion. In this work, a thermal nanophotonic-pyroelectric (TNPh-pyro) scheme consisting of a metamaterial multilayer and pyroelectric material, which performs synergistic waste heat rejection and photothermal heat-to-electricity conversion, is presented. Unlike any other pyroelectric configuration, this conceptual design deviates from the conventional by deliberately employing back-reflecting NIR to enable waste heat reutilization/recuperation to enhance pyroelectric generation, avoiding excessive solar heat uptake and also retaining high visual transparency of the device. Passive solar reflective cooling up to 4.1 °C is demonstrated. Meanwhile, the photothermal pyroelectric performance capitalizing on the back-reflecting effect shows an open circuit voltage (V oc ) and short circuit current (I sc ) enhancement of 152 and 146%, respectively. In addition, the designed photoactive component (TiO 2 /Cu) within the metamaterial multilayer provides the TNPh-pyro system with an effective air pollutant photodegradation functionality. Finally, proof-of-concept for concurrent photothermal management and enhanced solar pyroelectric generation under a real outdoor environment is demonstrated.

  1. Heat transfer and pressure drop characteristics of the tube bank fin heat exchanger with fin punched with flow redistributors and curved triangular vortex generators

    Science.gov (United States)

    Liu, Song; Jin, Hua; Song, KeWei; Wang, LiangChen; Wu, Xiang; Wang, LiangBi

    2017-10-01

    The heat transfer performance of the tube bank fin heat exchanger is limited by the air-side thermal resistance. Thus, enhancing the air-side heat transfer is an effective method to improve the performance of the heat exchanger. A new fin pattern with flow redistributors and curved triangular vortex generators is experimentally studied in this paper. The effects of the flow redistributors located in front of the tube stagnation point and the curved vortex generators located around the tube on the characteristics of heat transfer and pressure drop are discussed in detail. A performance comparison is also carried out between the fins with and without flow redistributors. The experimental results show that the flow redistributors stamped out from the fin in front of the tube stagnation points can decrease the friction factor at the cost of decreasing the heat transfer performance. Whether the combination of the flow redistributors and the curved vortex generators will present a better heat transfer performance depends on the size of the curved vortex generators. As for the studied two sizes of vortex generators, the heat transfer performance is promoted by the flow redistributors for the fin with larger size of vortex generators and the performance is suppressed by the flow redistributors for the fin with smaller vortex generators.

  2. The effects of heat generation and wall interaction on freezing and melting in a finite slab

    International Nuclear Information System (INIS)

    Cheung, F.B.; Chawla, T.C.; Pedersen, D.R.

    1984-01-01

    The processes of freezing and melting occurring in a heat-generating slab bounded by two semi-infinite cold walls is studied numerically. The method of collocation is employed to solve the various sets of governing equations describing the unsteady behavior of the system during different periods of time. Depending on the rate of internal heat generation and the thermal properties of the wall and the slab, several changes may take place in the system. These changes, as indicated by the transient locations of the solid-liquid interface, include transitions from freezing directly to melting, from freezing to cooling with phase change, from cooling to heating without phase change, and from heating to melting. Numerical predictions of the occurrence of these transitions, the rates of freezing and melting, and the duration of the transients are obtained as functions of several controlling dimensionless parameters of the system. Comparison is made with the case of a heat-generating sphere to further explore the effect of system geometry. (author)

  3. 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

  4. A study on heat transfer enhancement using flow channel inserts for thermoelectric power generation

    International Nuclear Information System (INIS)

    Lesage, Frédéric J.; Sempels, Éric V.; Lalande-Bertrand, Nathaniel

    2013-01-01

    Highlights: • Thermal enhancement in a thermoelectric liquid generator is tested. • Thermal enhancement is brought upon by flow impeding inserts. • CFD simulations attribute thermal enhancement to velocity field alterations. • Thermoelectric power enhancement is measured and discussed. • Power enhancement relative to adverse pressure drop is investigated. - Abstract: Thermoelectric power production has many potential applications that range from microelectronics heat management to large scale industrial waste-heat recovery. A low thermoelectric conversion efficiency of the current state of the art prevents wide spread use of thermoelectric modules. The difficulties lie in material conversion efficiency, module design, and thermal system management. The present study investigates thermoelectric power improvement due to heat transfer enhancement at the channel walls of a liquid-to-liquid thermoelectric generator brought upon by flow turbulating inserts. Care is taken to measure the adverse pressure drop due to the presence of flow impeding obstacles in order to measure the net thermoelectric power enhancement relative to an absence of inserts. The results illustrate the power enhancement performance of three different geometric forms fitted into the channels of a thermoelectric generator. Spiral inserts are shown to offer a minimal improvement in thermoelectric power production whereas inserts with protruding panels are shown to be the most effective. Measurements of the thermal enhancement factor which represents the ratio of heat flux into heat flux out of a channel and numerical simulations of the internal flow velocity field attribute the thermal enhancement resulting in the thermoelectric power improvement to thermal and velocity field synergy

  5. Equipment for secondary water distribution in heat exchanger, especially saturated steam generator for nuclear power plants and heat plants

    Energy Technology Data Exchange (ETDEWEB)

    Riman, J; Manek, O; Rybnicek, J

    1979-09-15

    A special structure consisting of a system of channels and a distribution plate with ports in-built above the tube-plate of a vertical-type steam generator prevents secondary water vaporization in the space above the tube-plate and thus also salt and sludge sedimentation which causes increased corrosion of heat transfer tubes. The size of the distribution plate ports is variable in the radial direction. The distribution plate is divided by means of the system of channels into at least two parts. The middle section of each part is of the through-flow type.

  6. Steam generation device with heat exchange between a liquid metal coolant and the feedwater

    International Nuclear Information System (INIS)

    Malaval, C.

    1983-01-01

    The invention is particularly applicable to a liquid metal fast breeder reactor plant, the liquid metal being sodium. The steam generation device is described in detail, it allows to get an upper liquid metal level without turbulence and an easier passage for the shock wave towards the steam generator up to the liquid metal level without being laterally reflected back to the intermediate heat exchangers [fr

  7. Co-optimized design of microchannel heat exchangers and thermoelectric generators

    DEFF Research Database (Denmark)

    Kolaei, Alireza Rezania; Yazawa, K.; Rosendahl, Lasse

    2013-01-01

    Designs of heat exchangers have mostly been disconnected to the performance of thermoelectric generator (TEG) systems. The development work, mostly focused on thermoelectric materials, required a significant amount of engineering parametric analysis. In this work, a micro plate-fin heat exchanger...... applied to a TEG is investigated and optimized to maximize the output power and the cost performance of generic TEG systems. The cost per performance is counted by a measure of price per power output ($/W). The channel width, channel height, fin thickness of heat exchanger, and fill factor of TEG...... are theoretically optimized for a wide range of pumping power. In conjunction with effective numeric tests, the model discusses the optimum size of the system components’ dimensions at two area sizes of the substrate plate of heat exchanger. Results show that at every pumping power, there are particular values...

  8. Nuclear heat generating plants - technical concepts and market potentials. Chapter 11

    International Nuclear Information System (INIS)

    Hasenkopf, O.; Erhard, W.D.; Nonnenmacher, A.; Hanselmann, M.

    1988-01-01

    Within the framework of a case study under the Federal Ministry of Research and Technology project 'Nuclear heat generating plants - technological concepts and market potentials', the possible applications of such plants were studied giving the district heat supply network of the Technische Werke der Stadt Stuttgart AG (Technical Works of the City of Stuttgart, Inc.) as an example. The use of district heating systems concentrated specifically on areas identified for economical supply because of their topographical position, existing heat density, distance from power plants, and a reasonable delimination from the available gas network. Based on the results of optimization calculations made by the Stuttgart Institute for Nuclear Technology and Energy Conversion, the required investment capital can be estimated as a function of the amount of fuel savings under the Stuttgart case study. (orig./UA) [de

  9. Micro scale CHP based on biomass intelligent heat transfer with thermoelectric generators

    Energy Technology Data Exchange (ETDEWEB)

    Moser, W.; Aigenbauer, S.; Heckmann, M.; Friedl, G. (Austrian Bioenergy Centre GmbH, Wieselburg (Austria)); Hofbauer, H. (Institute of Chemical Engineering, Vienna University of Technology (Austria))

    2007-07-01

    Pellet burners need auxiliary electrical power to provide CO{sub 2} balanced heat in a comfortable and environment friendly way. The idea is to produce this and some extra electricity within the device in order to save resources and to gain operation reliability and independency. An option for micro scale CHP is the usage of thermoelectric generators (TEGs). They allow direct conversion of heat into electrical power. They have the advantage of a long maintenance free durability and noiseless operation without moving parts or any working fluid. The useful heat remains almost unaffected and can still be used for heating. TEGs are predestined for the use in micro scale CHP based on solid biomass. In this paper the first results from the fully integrated prototype are presented. The performance of the TEG was observed for different loads and operating conditions in order to realise an optimised micro scale CHP based on solid biomass. (orig.)

  10. The thermoelectric generators use for waste heat utilization from cement plant

    Directory of Open Access Journals (Sweden)

    Sztekler Karol

    2017-01-01

    Production often entails the formation of by-product which is waste heat. One of the equipment processing heat into electricity is a thermoelectric generator. Its operation is based on the principle of thermoelectric phenomenon, which is known as a Seebeck phenomenon. The simplicity of thermoelectric phenomena allows its use in various industries, in which the main waste product is in the form of heat with the temperature of several hundred degrees. The study analyses the possibility of the thermoelectric systems use for the waste heat utilization resulting in the cement production at the cement plant. The location and design of the thermoelectric system that could be implemented in cement plant is chosen. The analysis has been prepared in the IPSEpro software.

  11. District heating system of Belgrade supplied from the co-generation plant 'Obrenovac' (Yugoslavia)

    International Nuclear Information System (INIS)

    Tomic, P.; Dobric, Z.; Studovic, M.

    2000-01-01

    The paper presents most relevant technical and economic features of the Project called 'System for supplying Belgrade with heat' (SDGB) from the thermal power plant 'Obrenovac', based on domestic coal and reconstruction of condensing power plant for combined generation of electricity and heat for the needs of municipal energy consumption. The system is designed for transport thermal energy, with capacity of 730 MJ/s from the Thermal Power Plant 'Nikola Tesla' / A to the existing heat plant 'Novi Beograd' based on the natural gas. The paper also gives the comparison of most important technical and economic features of 'SDGB' Project with the similar Project of District Heating System for supplying Prague with the thermal energy from Thermal Power Plant Melnik. (Author)

  12. Anisotropic frictional heating and defect generation in cyclotrimethylene-trinitramine molecular crystals

    Science.gov (United States)

    Rajak, Pankaj; Mishra, Ankit; Sheng, Chunyang; Tiwari, Subodh; Kalia, Rajiv K.; Nakano, Aiichiro; Vashishta, Priya

    2018-05-01

    Anisotropic frictional response and corresponding heating in cyclotrimethylene-trinitramine molecular crystals are studied using molecular dynamics simulations. The nature of damage and temperature rise due to frictional forces is monitored along different sliding directions on the primary slip plane, (010), and on non-slip planes, (100) and (001). Correlations between the friction coefficient, deformation, and frictional heating are established. We find that the friction coefficients on slip planes are smaller than those on non-slip planes. In response to sliding on a slip plane, the crystal deforms easily via dislocation generation and shows less heating. On non-slip planes, due to the inability of the crystal to deform via dislocation generation, a large damage zone is formed just below the contact area, accompanied by the change in the molecular ring conformation from chair to boat/half-boat. This in turn leads to a large temperature rise below the contact area.

  13. Generating a heated fluid using an electromagnetic radiation-absorbing complex

    Science.gov (United States)

    Halas, Nancy J.; Nordlander, Peter; Neumann, Oara

    2018-01-09

    A vessel including a concentrator configured to concentrate electromagnetic (EM) radiation received from an EM radiation source and a complex configured to absorb EM radiation to generate heat. The vessel is configured to receive a cool fluid from the cool fluid source, concentrate the EM radiation using the concentrator, apply the EM radiation to the complex, and transform, using the heat generated by the complex, the cool fluid to the heated fluid. The complex is at least one of consisting of copper nanoparticles, copper oxide nanoparticles, nanoshells, nanorods, carbon moieties, encapsulated nanoshells, encapsulated nanoparticles, and branched nanostructures. Further, the EM radiation is at least one of EM radiation in an ultraviolet region of an electromagnetic spectrum, in a visible region of the electromagnetic spectrum, and in an infrared region of the electromagnetic spectrum.

  14. Radiation heat transfer within an open-cycle MHD generator channel

    Science.gov (United States)

    Delil, A. A. M.

    1983-05-01

    Radiation heat transfer in an MHD generator was modeled using the Sparrow and Cess model for radiation in an emitting, absorbing and scattering medium. The resulting general equations can be considerably reduced by introducing simplifying approximations for the channel and MHD gas properties. The simplifications lead to an engineering model, which is very useful for one-dimensional channel flow approximation. The model can estimate thermo-optical MHD gas properties, which can be substituted in the energy equation. The model considers the contribution of solid particles in the MHD gas to radiation heat transfer, considerable in coal-fired closed cycle MHD generators. The modeling is applicable also for other types of flow at elevated temperatures, where radiation heat transfer is an important quantity.

  15. The General-Purpose Heat Source Radioisotope Thermoelectric Generator: Power for the Galileo and Ulysses missions

    International Nuclear Information System (INIS)

    Bennett, G.L.; Lombardo, J.J.; Hemler, R.J.; Peterson, J.R.

    1986-01-01

    Electrical power for NASA's Galileo mission to Jupiter and ESA's Ulysses mission to explore the polar regions of the Sun will be provided by General-Purpose Heat Source Radioisotope Thermo-electric Generators (GPHS-RTGs). Building upon the successful RTG technology used in the Voyager program, each GPHS-RTG will provide at least 285 W(e) at beginning-of-mission. The design concept has been proven through extensive tests of an electrically heated Engineering Unit and a nuclear-heated Qualification Unit. Four flight generators have been successfully assembled and tested for use on the Galileo and Ulysses spacecraft. All indications are that the GPHS-RTGs will meet or exceed the power requirement of the missions

  16. Experimental investigations on waterside corrosion problems of sodium-heated steam generators

    International Nuclear Information System (INIS)

    Buescher, E.; Haubold, W.; Jansing, W.; Vinzens, K.

    1975-01-01

    Based on experimental results, it is shown that the formation of a protective magnetite layer in sodium-heated steam generators - operated with neutral demineralized water - proceeds very fast. The stability of the magnetite layer is excellent even at sudden load changes and at the start-up or shut-down operation. (author)

  17. Numerical Investigation of Heat Transfer Augmentation through Geometrical Optimization of Vortex Generators

    DEFF Research Database (Denmark)

    Gorji, Mofid; Mirgolbabaei, Hessam; Barari, Amin

    2010-01-01

    In this paper a two-dimensional numerical simulation of a steady incompressible and turbulent model has been carried out to study the effects of vortex generators in a compact heat exchanger in a curvilinear coordinate system. The mesh which is applied in this study is boundary fitted and has been...

  18. Numerical Analysis on Longitudinal Location Optimization of Vortex Generator in Compact Heat Exchangers

    DEFF Research Database (Denmark)

    Gorji, M.; Mirgolbababei, H.; Barari, Amin

    2011-01-01

    In this paper, numerical, curvilinear and turbulent model has been used to investigate the effect of vortex generator's longitudinal displacement on heat transfer and fluid flow in different Reynolds numbers ranging from 500 to 3000. The numerical model has been validated with experimental results...

  19. Heat priming induces trans-generational tolerance to high temperature stress in wheat

    Directory of Open Access Journals (Sweden)

    Xiao eWang

    2016-04-01

    Full Text Available Wheat plants are very sensitive to high temperature stress during grain filling. Effects of heat priming applied to the first generation on tolerance of the successive generation to post-anthesis high temperature stress were investigated. Compared with the progeny of non-heat primed plants (NH, the progeny of heat-primed plants (PH possessed higher grain yield, leaf photosynthesis and activities of antioxidant enzymes and lower cell membrane damage under high temperature stress. In the transcriptome profile, 1430 probes showed obvious difference in expression between PH and NH. These genes were related to signal transduction, transcription, energy, defense, and protein destination and storage, respectively. The gene encoding the lysine-specific histone demethylase 1 (LSD1 which was involved in histone demethylation related to epigenetic modification was up-regulated in the PH compared with NH. The proteome analysis indicated that the proteins involved in photosynthesis, energy production and protein destination and storage were up-regulated in the PH compared with NH. In short, thermos-tolerance was induced through heritable epigenetic alternation and signaling transduction, both processes further triggered prompt modifications of defense related responses in anti-oxidation, transcription, energy production, and protein destination and storage in the progeny of the primed plants under high temperature stress. It was concluded that trans-generation thermo-tolerance was induced by heat priming in the first generation, and this might be an effective measure to cope with severe high-temperature stresses during key growth stages in wheat production.

  20. Analysis and modeling of localized heat generation by tumor-targeted nanoparticles (Monte Carlo methods)

    Science.gov (United States)

    Sanattalab, Ehsan; SalmanOgli, Ahmad; Piskin, Erhan

    2016-04-01

    We investigated the tumor-targeted nanoparticles that influence heat generation. We suppose that all nanoparticles are fully functionalized and can find the target using active targeting methods. Unlike the commonly used methods, such as chemotherapy and radiotherapy, the treatment procedure proposed in this study is purely noninvasive, which is considered to be a significant merit. It is found that the localized heat generation due to targeted nanoparticles is significantly higher than other areas. By engineering the optical properties of nanoparticles, including scattering, absorption coefficients, and asymmetry factor (cosine scattering angle), the heat generated in the tumor's area reaches to such critical state that can burn the targeted tumor. The amount of heat generated by inserting smart agents, due to the surface Plasmon resonance, will be remarkably high. The light-matter interactions and trajectory of incident photon upon targeted tissues are simulated by MIE theory and Monte Carlo method, respectively. Monte Carlo method is a statistical one by which we can accurately probe the photon trajectories into a simulation area.

  1. Certification of materials for steam generator condensor and regeneration heat exchanger for nuclear plant

    International Nuclear Information System (INIS)

    Stevanovicj, M.V.; Jovashevicj, V.J.; Jovashevicj, V.D.J.; Spasicj, Zh.Lj.

    1977-01-01

    In the construction of a nuclear power plant almost all known materials are used. The choice depends on working conditions. In this work standard specifications of contemporary materials that take part in larger quantities in the following components of the secondary circuit of PWR-type nuclear power plant are proposed: steam generator with moisture separator, condensor and regenerative heat eXchanger

  2. Heat generation in agglomerated ferrite nanoparticles in an alternating magnetic field

    International Nuclear Information System (INIS)

    Lima, E Jr; De Biasi, E; Mansilla, M Vasquez; Saleta, M E; Granada, M; Troiani, H E; Zysler, R D; Effenberger, F B; Rossi, L M; Rechenberg, H R

    2013-01-01

    The role of agglomeration and magnetic interparticle interactions in heat generation of magnetic ferrofluids in an ac magnetic field is still unclear, with apparent discrepancy between the results presented in the literature. In this work, we measured the heat generating capability of agglomerated ferrite nanoparticles in a non-invasive ac magnetic field with f = 100 kHz and H 0 = 13 kA m -1 . The nanoparticles were morphologically and magnetically characterized, and the specific absorption rate (SAR) for our ac magnetic field presents a clear dependence on the diameter of the nanoparticles, with a maximum SAR = 48 W g -1 for 15 nm. Our agglomerated nanoparticles have large hydrodynamic diameters, thus the mechanical relaxation can be neglected as a heat generation mechanism. Therefore, we present a model that simulates the SAR dependence of the agglomerated samples on the diameter of the nanoparticles based on the hysteresis losses that is valid for the non-linear region (with H 0 comparable to the anisotropy field). Our model takes into account the magnetic interactions among the nanoparticles in the agglomerate. For comparison, we also measured the SAR of non-agglomerated nanoparticles in a similar diameter range, in which Néel and Brown relaxations dominate the heat generation.

  3. Experimental investigations on waterside corrosion problems of sodium-heated steam generators

    Energy Technology Data Exchange (ETDEWEB)

    Buescher, E; Haubold, W; Jansing, W; Vinzens, K

    1975-07-01

    Based on experimental results, it is shown that the formation of a protective magnetite layer in sodium-heated steam generators - operated with neutral demineralized water - proceeds very fast. The stability of the magnetite layer is excellent even at sudden load changes and at the start-up or shut-down operation. (author)

  4. Options for greenhouse emission reduction by using a module for combined heat and power generation

    International Nuclear Information System (INIS)

    Stankov, Nikola; Ivanov, Bozhidar

    2009-01-01

    This report contains example of CO 2 emission reduction assessment when using module for combined heat and power generation that is fueled by natural gas. Environmental benefits are related to the type of fuel that is used and the increased efficiency of the combined production process. Choosing of the CHP unit and the assessment scheme are also presented

  5. Selenide isotope generator for the Galileo Mission. Axially-grooved heat pipe: accelerated life test results

    International Nuclear Information System (INIS)

    1979-08-01

    The results through SIG/Galileo contract close-out of accelerated life testing performed from June 1978 to June 1979 on axially-grooved, copper/water heat pipes are presented. The primary objective of the test was to determine the expected lifetime of axially-grooved copper/water heat pipes. The heat pipe failure rate, due to either a leak or a build-up of non-condensible gas, was determined. The secondary objective of the test was to determine the effects of time and temperature on the thermal performance parameters relevant to long-term (> 50,000 h) operation on a space power generator. The results showed that the gas generation rate appears to be constant with time after an initial sharp rise although there are indications that it drops to approximately zero beyond approx. 2000 h. During the life test, the following pipe-hours were accumulated: 159,000 at 125 0 C, 54,000 at 165 0 C, 48,000 at 185 0 C, and 8500 at 225 0 C. Heated hours per pipe ranged from 1000 to 7500 with an average of 4720. Applying calculated acceleration factors yields the equivalent of 930,000 pipe-h at 125 0 C. Including the accelerated hours on vendor tested pipes raises this number to 1,430,000 pipe-hours at 125 0 C. It was concluded that, for a heat pipe temperature of 125 0 C and a mission time of 50,000 h, the demonstrated heat pipe reliability is between 80% (based on 159,000 actual pipe-h at 125 0 C) and 98% (based on 1,430,000 accelerated pipe-h at 125 0 C). Measurements indicate some degradation of heat transfer with time, but no detectable degradation of heat transport

  6. High-temperature and high-power-density nanostructured thermoelectric generator for automotive waste heat recovery

    International Nuclear Information System (INIS)

    Zhang, Yanliang; Cleary, Martin; Wang, Xiaowei; Kempf, Nicholas; Schoensee, Luke; Yang, Jian; Joshi, Giri; Meda, Lakshmikanth

    2015-01-01

    Highlights: • A thermoelectric generator (TEG) is fabricated using nanostructured half-Heusler materials. • The TE unicouple devices produce superior power density above 5 W/cm"2. • A TEG system with over 1 kW power output is demonstrated by recovering automotive waste heat. - Abstract: Given increasing energy use as well as decreasing fossil fuel sources worldwide, it is no surprise that interest in promoting energy efficiency through waste heat recovery is also increasing. Thermoelectric generators (TEGs) are one of the most promising pathways for waste heat recovery. Despite recent thermoelectric efficiency improvement in nanostructured materials, a variety of challenges have nevertheless resulted in few demonstrations of these materials for large-scale waste heat recovery. Here we demonstrate a high-performance TEG by combining high-efficiency nanostructured bulk materials with a novel direct metal brazing process to increase the device operating temperature. A unicouple device generates a high power density of 5.26 W cm"−"2 with a 500 °C temperature difference between hot and cold sides. A 1 kW TEG system is experimentally demonstrated by recovering the exhaust waste heat from an automotive diesel engine. The TEG system operated with a 2.1% heat-to-electricity efficiency under the average temperature difference of 339 °C between the TEG hot- and cold-side surfaces at a 550 °C exhaust temperature. The high-performance TEG reported here open up opportunities to use TEGs for energy harvesting and power generation applications.

  7. Joule-heated glass-furnace system for the incineration of low-level radioactive wastes

    International Nuclear Information System (INIS)

    Armstrong, K.M.; Klingler, L.M.; Doty, J.W.; Kramer, D.P.

    1982-01-01

    For the past 1-1/2 years, Mound has been preparing and evaluating a commercially available joule-heated glass furnace unit, coupled with a wet scrubbing system. The purpose of the glass furnace evaluation is to advance and document incinerator technology for such combustibles as solids, resins, and sludges, and to develop a stable waste form for subsequent disposal. Four (4) waste nonradioactive types were selected to determine the combustion efficiency of the furnace unit: (1) dry solid waste composed of paper, plastics, rubber, and cloth, (2) ion exchange resin of both the anionic and cationic type, (3) filter sludge composed of diatomaceous earth, organic cellulosic filter aid, and powdered ion exchange resin, and (4) cartridge filters having glass and plastic filter surfaces and nonmetallic cores. When completed, the combustion efficiency experiments for the proposed nonradioactive waste-types revealed the ability of the furnace to easily incinerate waste at feedrates of up to 150 lb/hr. During the course of the experiments, combustibles in the offgas remained consistently low, suggesting excellent combustion efficiency. Furthermore, ash produced by the combustion process was effectively incorporated into the melt by convective currents in the glass. Future work on the glass furnace incinerator will include spiking the waste to determine radioisotope behavior in the furnace

  8. Selection of efficient options for processing and storage of radioactive waste in countries with small amounts of waste generation

    International Nuclear Information System (INIS)

    2003-09-01

    The report is intended to assist decision makers in countries using nuclear energy for non-power applications to organize their waste management practices. It describes methodologies, criteria and options for the selection of appropriate technologies for processing and storage of low and intermediate level radioactive waste from different nuclear applications. The report reviews both technical and non-technical factors important for decision making and planning, and for implementation of waste management activities at the country and facility levels. It makes practical recommendations for the selection of particular technologies for different scales of waste generation. These wastes may arise from production of radionuclides and their application in industry, agriculture, medicine, education and research. The report also considers waste generated at research reactors, research centers and research laboratories using radioisotopes, as well as waste from decommissioning of research reactors and small nuclear facilities such as hot cells, laboratories and irradiation facilities. Management of uranium mining and milling waste and management of spent fuel from research reactors are not considered in this report. Discussed in detail are: the basic legal, regulatory, administrative and technical requirements set up in a national waste management system and review of the factors and components affecting the selection of an appropriate national waste management system. the origins and characteristics of radioactive waste from different nuclear applications. the technical factors that might affect the selection of waste processing and storage technologies, the main waste management steps, information on available technologies, the basis for planning of waste processing and storage and the selection of a particular option for radioactive waste processing and storage in countries with a different scale of nuclear applications

  9. Selection of efficient options for processing and storage of radioactive waste in countries with small amounts of waste generation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-09-01

    The report is intended to assist decision makers in countries using nuclear energy for non-power applications to organize their waste management practices. It describes methodologies, criteria and options for the selection of appropriate technologies for processing and storage of low and intermediate level radioactive waste from different nuclear applications. The report reviews both technical and non-technical factors important for decision making and planning, and for implementation of waste management activities at the country and facility levels. It makes practical recommendations for the selection of particular technologies for different scales of waste generation. These wastes may arise from production of radionuclides and their application in industry, agriculture, medicine, education and research. The report also considers waste generated at research reactors, research centers and research laboratories using radioisotopes, as well as waste from decommissioning of research reactors and small nuclear facilities such as hot cells, laboratories and irradiation facilities. Management of uranium mining and milling waste and management of spent fuel from research reactors are not considered in this report. Discussed in detail are: the basic legal, regulatory, administrative and technical requirements set up in a national waste management system and review of the factors and components affecting the selection of an appropriate national waste management system. the origins and characteristics of radioactive waste from different nuclear applications. the technical factors that might affect the selection of waste processing and storage technologies, the main waste management steps, information on available technologies, the basis for planning of waste processing and storage and the selection of a particular option for radioactive waste processing and storage in countries with a different scale of nuclear applications.

  10. Microbial aspects of gas generation from low level radioactive waste simulant

    International Nuclear Information System (INIS)

    Kidby, D.W.; Billington, R.S.

    1992-01-01

    This report details the experimental work undertaken to further the understanding of the kinetics of methanogenesis associated with radioactive LLW disposal. A series of treatments were established by inoculating a LLW simulant and investigating the kinetics of methanogenesis in small Wheaton bottles. Treatments were set up to study the effects of waste compaction, the addition of metal to the simulant, the initial aerobic phase, pH and temperature on gas production. A separate experiment was also established to determine whether cellulose in the simulant acted as a biogas precursor. Results are presented from the head space gas analysis and the solid and liquid phase analyses undertaken over a 600 day period. (Author)

  11. Techno-economic analysis of using corn stover to supply heat and power to a corn ethanol plant - Part 2: Cost of heat and power generation systems

    International Nuclear Information System (INIS)

    Mani, S.; Sokhansanj, S.; Tagore, S.; Turhollow, A.F.

    2010-01-01

    This paper presents a techno-economic analysis of corn stover fired process heating (PH) and the combined heat and power (CHP) generation systems for a typical corn ethanol plant (ethanol production capacity of 170 dam 3 ). Discounted cash flow method was used to estimate both the capital and operating costs of each system and compared with the existing natural gas fired heating system. Environmental impact assessment of using corn stover, coal and natural gas in the heat and/or power generation systems was also evaluated. Coal fired process heating (PH) system had the lowest annual operating cost due to the low fuel cost, but had the highest environmental and human toxicity impacts. The proposed combined heat and power (CHP) generation system required about 137 Gg of corn stover to generate 9.5 MW of electricity and 52.3 MW of process heat with an overall CHP efficiency of 83.3%. Stover fired CHP system would generate an annual savings of 3.6 M$ with an payback period of 6 y. Economics of the coal fired CHP system was very attractive compared to the stover fired CHP system due to lower fuel cost. But the greenhouse gas emissions per Mg of fuel for the coal fired CHP system was 32 times higher than that of stover fired CHP system. Corn stover fired heat and power generation system for a corn ethanol plant can improve the net energy balance and add environmental benefits to the corn to ethanol biorefinery.

  12. Development of a geopolymer solidification method for radioactive wastes by compression molding and heat curing

    International Nuclear Information System (INIS)

    Shimoda, Chiaki; Matsuyama, Kanae; Okabe, Hirofumi; Kaneko, Masaaki; Miyamoto, Shinya

    2017-01-01

    Geopolymer solidification is a good method for managing waste because of it is inexpensive as compared with vitrification and has a reduced risk of hydrogen generation. In general, when geopolymers are made, water is added to the geopolymer raw materials, and then the slurry is mixed, poured into a mold, and cured. However, it is difficult to control the reaction because, depending on the types of materials, the viscosity can immediately increase after mixing. Slurries of geopolymers easily attach to the agitating wing of the mixer and easily clog the plumbing during transportation. Moreover, during long-term storage of solidified wastes containing concentrated radionuclides in a sealed container without vents, the hydrogen concentration in the container increases over time. Therefore, a simple method using as little water as possible is needed. In this work, geopolymer solidification by compression molding was studied. As compared with the usual methods, it provides a simple and stable method for preparing waste for long-term storage. From investigations performed before and after solidification by compression molding, it was shown that the crystal structure changed. From this result, it was concluded that the geopolymer reaction proceeded during compression molding. This method (1) reduces the energy needed for drying, (2) has good workability, (3) reduces the overall volume, and (4) reduces hydrogen generation. (author)

  13. Method of producing a solution of radioactive lanthanum-140 from radioactive barium-140 in an isotope generator and installation to carry out the method

    International Nuclear Information System (INIS)

    Akerman, K.; Jacobs, G.; Sauerwein, K.

    1979-01-01

    A method of separating radioactive lanthanum-140 from radioactive Ba-140 is proposed. The lanthanum-140 will be washed out of a sulphate precipitate and separated from Ba-140-sulphate by a granular filter mass of CaSO 4 and BaSO 4 . Details of the process are given. (UWI) [de

  14. Optimization of the energy resolution and of the radioactive background rejection for ionization-heat detectors equipped with thermometric thin films for the direct WIMPs detection

    International Nuclear Information System (INIS)

    Dolgorouky, Y.W.

    2008-09-01

    The EDELWEISS experiment aims at the direct detection of WIMPs as possible candidates for dark matter. It uses heat-and-ionization detectors that can discriminate these particles from the radioactive background. To date, this method is limited by events with incomplete charge collection that occur just beneath the detectors electrodes. In order to identify and reject these undesirable events, we have developed detectors equipped with thin films used both as thermometers - and hence sensitive to the transient athermal regime - and as electrodes for the charge collection. This thesis focuses on the optimization of such thin films regarding surface events rejection and on the modelling of the physical processes enabling this identification. The optimization must both maximize the fiducial volume and conserve an energy resolution such that the recoil energy threshold is of the order of 30 keV. Our work explores four generations of detectors each of which corresponds to successive evolutions in their conception. In all cases, the electrode-thermometer is an amorphous Anderson insulator NbSi thin film polarized by two interleaved comb-shaped niobium electrodes. In spite of constant progress in the successive detectors performances, the latest generation does not display the performances required for the EDELWEISS II experiment. Our work has shown the difficulty of the transient thermal signal modelling due to the complex contribution of the charge collection. This works has lead to new ideas regarding the detectors configuration, so that the athermal regime can be optimized to enhance both the rejection capability and the resolution. (author)

  15. Research highlights : study of the noise generated by heat pumps in residential areas

    International Nuclear Information System (INIS)

    Rousseau, J.

    2000-01-01

    Rising energy costs and aggressive marketing played a major role in the substantial increase in the number of domestic heat pumps installed. As a rule, heat pumps are connected to the heating and ventilation systems on the outside of the house. Whether the heat pump is equipped with an integrated compressor or not, it creates noise. The noise is generated by the powerful fan designed to cool all the coils, and also by the compressor itself and the circulation of the refrigerant gas. Some municipalities received so many complaints on this topic that they are considering adopting noise bylaws. The first objective of the research undertaken by Canada Mortgage and Housing Corporation on heat pumps in residential areas was to analyze the noise pollution mode of commonly used heat pumps. A study of a simple noise reduction device was performed, and the extent to which it should be used. Finally, there had to be no reduction of the thermal capacities of the pumps. Phase 1 of the study took place between May and August 1990, in the area of Quebec City. A total of 125 heat pumps were identified. The four major manufacturers were Trane, Carrier, York, and Lennox. Initial sound pressure levels measurements were made at one metre from the unit, for 80 such units, respecting the ratio by brands in the sample of 125. A detailed global noise measurement determined the sound power of each pump. A detailed muffler feasibility study was then conducted, using a Trane heat pump. The results of the study indicated that heat pumps were a major source of continuous noise in low and mid-density areas. It was discovered that a noise attenuation device could always be built around heat pumps, which needed to be installed as close as possible to the casing of the heat pump. It is not possible to design a device to fit each and every heat pump, the design is specific to the dimensions and characteristics of each model of heat pump. The thermal performance of the pumps will not be affected by

  16. Performance analysis of a waste heat recovery thermoelectric generation system for automotive application

    International Nuclear Information System (INIS)

    Liu, X.; Deng, Y.D.; Li, Z.; Su, C.Q.

    2015-01-01

    Graphical abstract: A new automotive exhaust-based thermoelectric generator and its “four-TEGs” system are constructed, and the performance characteristics of system are discussed through road test and revolving drum test. - Highlights: • The automotive thermoelectric generator system was constructed and studied. • Road test and revolving drum test were used to measure the output power. • A performance of 201.7 V (open circuit voltage)/944 W obtained. - Abstract: Thermoelectric power generators are one of the promising green energy sources. In this case study, an energy-harvesting system which extracts heat from an automotive exhaust pipe and turns the heat into electricity by using thermoelectric power generators (TEGs) has been constructed. The test bench is developed to analysis the performance of TEG system characteristics, which are undertaken to assess the feasibility of automotive applications. Based on the test bench, a new system called “four-TEGs” system is designed and assembled into prototype vehicle called “Warrior”, through the road test and revolving drum test table, characteristics of the system such as hot-side temperature, cold-side temperature, open circuit voltage and power output are studied, and a maximum power of 944 W was obtained, which completely meets the automotive application. The present study shows the promising potential of using this kind of thermoelectric generator for low-temperature waste heat recovery vehicle

  17. The effect of turbulence-radiation interaction on radiative entropy generation and heat transfer

    International Nuclear Information System (INIS)

    Caldas, Miguel; Semiao, Viriato

    2007-01-01

    The analysis under the second law of thermodynamics is the gateway for optimisation in thermal equipments and systems. Through entropy minimisation techniques it is possible to increase the efficiency and overall performance of all kinds of thermal systems. Radiation, being the dominant mechanism of heat transfer in high-temperature systems, plays a determinant role in entropy generation within such equipments. Turbulence is also known to be a major player in the phenomenon of entropy generation. Therefore, turbulence-radiation interaction is expected to have a determinant effect on entropy generation. However, this is a subject that has not been dealt with so far, at least to the extent of the authors' knowledge. The present work attempts to fill that void, by studying the effect of turbulence-radiation interaction on entropy generation. All calculations are approached in such a way as to make them totally compatible with standard engineering methods for radiative heat transfer, namely the discrete ordinates method. It was found that turbulence-radiation interaction does not significantly change the spatial pattern of entropy generation, or heat transfer, but does change significantly their magnitude, in a way approximately proportional to the square of the intensity of turbulence

  18. Design of wearable hybrid generator for harvesting heat energy from human body depending on physiological activity

    Science.gov (United States)

    Kim, Myoung-Soo; Kim, Min-Ki; Kim, Kyongtae; Kim, Yong-Jun

    2017-09-01

    We developed a prototype of a wearable hybrid generator (WHG) that is used for harvesting the heat energy of the human body. This WHG is constructed by integrating a thermoelectric generator (TEG) in a circular mesh polyester knit fabric, circular-shaped pyroelectric generator (PEG), and quick sweat-pickup/dry-fabric. The fabric packaging enables the TEG part of the WHG to generate energy steadily while maintaining a temperature difference in extreme temperature environments. Moreover, when the body sweats, the evaporation heat of the sweat leads to thermal fluctuations in the WHG. This phenomenon further leads to an increase in the output power of the WHG. These characteristics of the WHG make it possible to produce electrical energy steadily without reduction in the conversion efficiency, as both TEG and PEG use the same energy source of the human skin and the ambient temperature. Under a temperature difference of ˜6.5 °C and temperature change rate of ˜0.62 °C s-1, the output power and output power density of the WHG, respectively, are ˜4.5 nW and ˜1.5 μW m-2. Our hybrid approach will provide a framework to enhance the output power of the wearable generators that harvest heat energy from human body in various environments.

  19. Entropy generation due to external fluid flow and heat transfer from a cylinder between parallel planes

    Directory of Open Access Journals (Sweden)

    Melhem Omar A.

    2017-01-01

    Full Text Available In the present study, second law analysis is introduced for circular cylinder confined between parallel planes. An analytical approach is adopted to study the effects of block age, Reynolds and Prandtl numbers on the entropy generation due to the laminar flow and heat transfer. Four different fluids are considered in the present analysis for comparison purposes. Heat transfer for the cylinder at an isothermal boundary condition is incorporated. In general, the entropy generation rate decreases as the blockage ratio decreases. In addition, the entropy generation rate increases with increasing Reynolds and Prandtl numbers. At a fixed Reynolds number, the effect of block age becomes more notice able for higher Prandtl number fluid. Similarly, for the same fluid, the effect of block age becomes more no tice able as the Reynolds number increases.

  20. Geothermal electricity generation and desalination: an integrated process design to conserve latent heat with operational improvements

    KAUST Repository

    Missimer, Thomas M.

    2016-02-05

    A new process combination is proposed to link geothermal electricity generation with desalination. The concept involves maximizing the utilization of harvested latent heat by passing the turbine exhaust steam into a multiple effect distillation system and then into an adsorption desalination system. Processes are fully integrated to produce electricity, desalted water for consumer consumption, and make-up water for the geothermal extraction system. Further improvements in operational efficiency are achieved by adding a seawater reverse osmosis system to the site to utilize some of the generated electricity and using on-site aquifer storage and recovery to maximize water production with tailoring of seasonal capacity requirements and to meet facility maintenance requirements. The concept proposed conserves geothermally harvested latent heat and maximizes the economics of geothermal energy development. Development of a fully renewable energy electric generation-desalination-aquifer storage campus is introduced within the framework of geothermal energy development. © 2016 The Author(s). Published by Taylor & Francis