National Library of Energy BETA

Sample records for approximate heat rates

  1. ARM - Measurement - Radiative heating rate

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    govMeasurementsRadiative heating rate ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Radiative heating rate The heating rate due to the divergence of long and shortwave radiative flux. Categories Radiometric, Atmospheric State Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a

  2. Combined Retrieval, Microphysical Retrievals and Heating Rates

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Feng, Zhe

    2013-02-22

    Microphysical retrievals and heating rates from the AMIE/Gan deployment using the PNNL Combined Retrieval.

  3. Combined Retrieval, Microphysical Retrievals and Heating Rates

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Feng, Zhe

    Microphysical retrievals and heating rates from the AMIE/Gan deployment using the PNNL Combined Retrieval.

  4. Combined Retrieval, Microphysical Retrievals and Heating Rates...

    Office of Scientific and Technical Information (OSTI)

    Shortwave broadband total upwelling irradiance; Liquid water content; Liquid water path; Radiative heating rate Dataset File size NAView Dataset View Dataset DOI: 10.5439116949

  5. MULTI-SCALE MODELING AND APPROXIMATION ASSISTED OPTIMIZATION OF BARE TUBE HEAT EXCHANGERS

    SciTech Connect (OSTI)

    Bacellar, Daniel; Ling, Jiazhen; Aute, Vikrant; Radermacher, Reinhard; Abdelaziz, Omar

    2014-01-01

    Air-to-refrigerant heat exchangers are very common in air-conditioning, heat pump and refrigeration applications. In these heat exchangers, there is a great benefit in terms of size, weight, refrigerant charge and heat transfer coefficient, by moving from conventional channel sizes (~ 9mm) to smaller channel sizes (< 5mm). This work investigates new designs for air-to-refrigerant heat exchangers with tube outer diameter ranging from 0.5 to 2.0mm. The goal of this research is to develop and optimize the design of these heat exchangers and compare their performance with existing state of the art designs. The air-side performance of various tube bundle configurations are analyzed using a Parallel Parameterized CFD (PPCFD) technique. PPCFD allows for fast-parametric CFD analyses of various geometries with topology change. Approximation techniques drastically reduce the number of CFD evaluations required during optimization. Maximum Entropy Design method is used for sampling and Kriging method is used for metamodeling. Metamodels are developed for the air-side heat transfer coefficients and pressure drop as a function of tube-bundle dimensions and air velocity. The metamodels are then integrated with an air-to-refrigerant heat exchanger design code. This integration allows a multi-scale analysis of air-side performance heat exchangers including air-to-refrigerant heat transfer and phase change. Overall optimization is carried out using a multi-objective genetic algorithm. The optimal designs found can exhibit 50 percent size reduction, 75 percent decrease in air side pressure drop and doubled air heat transfer coefficients compared to a high performance compact micro channel heat exchanger with same capacity and flow rates.

  6. Broadband Heating Rate Profile Project (BBHRP) - SGP ripbe1mcfarlane

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Riihimaki, Laura; Shippert, Timothy

    2014-11-05

    The objective of the ARM Broadband Heating Rate Profile (BBHRP) Project is to provide a structure for the comprehensive assessment of our ability to model atmospheric radiative transfer for all conditions. Required inputs to BBHRP include surface albedo and profiles of atmospheric state (temperature, humidity), gas concentrations, aerosol properties, and cloud properties. In the past year, the Radiatively Important Parameters Best Estimate (RIPBE) VAP was developed to combine all of the input properties needed for BBHRP into a single gridded input file. Additionally, an interface between the RIPBE input file and the RRTM was developed using the new ARM integrated software development environment (ISDE) and effort was put into developing quality control (qc) flags and provenance information on the BBHRP output files so that analysis of the output would be more straightforward. This new version of BBHRP, sgp1bbhrpripbeC1.c1, uses the RIPBE files as input to RRTM, and calculates broadband SW and LW fluxes and heating rates at 1-min resolution using the independent column approximation. The vertical resolution is 45 m in the lower and middle troposphere to match the input cloud properties, but is at coarser resolution in the upper atmosphere. Unlike previous versions, the vertical grid is the same for both clear-sky and cloudy-sky calculations.

  7. Broadband Heating Rate Profile Project (BBHRP) - SGP ripbe370mcfarlane

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Riihimaki, Laura; Shippert, Timothy

    2014-11-05

    The objective of the ARM Broadband Heating Rate Profile (BBHRP) Project is to provide a structure for the comprehensive assessment of our ability to model atmospheric radiative transfer for all conditions. Required inputs to BBHRP include surface albedo and profiles of atmospheric state (temperature, humidity), gas concentrations, aerosol properties, and cloud properties. In the past year, the Radiatively Important Parameters Best Estimate (RIPBE) VAP was developed to combine all of the input properties needed for BBHRP into a single gridded input file. Additionally, an interface between the RIPBE input file and the RRTM was developed using the new ARM integrated software development environment (ISDE) and effort was put into developing quality control (qc) flags and provenance information on the BBHRP output files so that analysis of the output would be more straightforward. This new version of BBHRP, sgp1bbhrpripbeC1.c1, uses the RIPBE files as input to RRTM, and calculates broadband SW and LW fluxes and heating rates at 1-min resolution using the independent column approximation. The vertical resolution is 45 m in the lower and middle troposphere to match the input cloud properties, but is at coarser resolution in the upper atmosphere. Unlike previous versions, the vertical grid is the same for both clear-sky and cloudy-sky calculations.

  8. Spatially resolved heat release rate measurements in turbulent premixed flames

    SciTech Connect (OSTI)

    Ayoola, B.O.; Kaminski, C.F.; Balachandran, R.; Mastorakos, E.; Frank, J.H.

    2006-01-01

    Heat release rate is a fundamental property of great importance for the theoretical and experimental elucidation of unsteady flame behaviors such as combustion noise, combustion instabilities, and pulsed combustion. Investigations of such thermoacoustic interactions require a reliable indicator of heat release rate capable of resolving spatial structures in turbulent flames. Traditionally, heat release rate has been estimated via OH or CH radical chemiluminescence; however, chemiluminescence suffers from being a line-of-sight technique with limited capability for resolving small-scale structures. In this paper, we report spatially resolved two-dimensional measurements of a quantity closely related to heat release rate. The diagnostic technique uses simultaneous OH and CH{sub 2}O planar laser-induced fluorescence (PLIF), and the pixel-by-pixel product of the OH and CH{sub 2}O PLIF signals has previously been shown to correlate well with local heat release rates. Results from this diagnostic technique, which we refer to as heat release rate imaging (HR imaging), are compared with traditional OH chemiluminescence measurements in several flames. Studies were performed in lean premixed ethylene flames stabilized between opposed jets and with a bluff body. Correlations between bulk strain rates and local heat release rates were obtained and the effects of curvature on heat release rate were investigated. The results show that the heat release rate tends to increase with increasing negative curvature for the flames investigated for which Lewis numbers are greater than unity. This correlation becomes more pronounced as the flame gets closer to global extinction.

  9. Sensitivity of Radiative Fluxes and Heating Rates to Cloud Microphysics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Sensitivity of Radiative Fluxes and Heating Rates to Cloud Microphysics S. F. Iacobellis and R. C. J. Somerville Scripps Institution of Oceanography University of California, San Diego La Jolla, California G. M. McFarquhar University of Illinois at Urbana-Champaign Urbana, Illinois D. L. Mitchell Desert Research Institute Reno, Nevada Introduction A single-column model (SCM) is used to examine the sensitivity of basic quantities such as atmospheric radiative heating rates and surface and top of

  10. Status of the Broadband Heating Rate Profile (BBHRP) VAP

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Status of the Broadband Heating Rate Profile (BBHRP) VAP Mlawer, Eli Atmospheric & Environmental Research, Inc. Clough, Shepard Atmospheric and Environmental Research Delamere, Jennifer Atmospheric and Environmental Research, Inc. Miller, Mark Brookhaven National Laboratory Johnson, Karen Brookhaven National Laboratory Troyan, David Brookhaven National Laboratory Jensen, Michael Brookhaven National Laboratory Shippert, Timothy Pacific Northwest National Laboratory Long, Chuck Pacific

  11. High heating rate thermal desorption for molecular surface sampling

    DOE Patents [OSTI]

    Ovchinnikova, Olga S.; Van Berkel, Gary J.

    2016-03-29

    A method for analyzing a sample having at least one analyte includes the step of heating the sample at a rate of at least 10.sup.6 K/s to thermally desorb at least one analyte from the sample. The desorbed analyte is collected. The analyte can then be analyzed.

  12. Standby Rates for Combined Heat and Power Systems

    SciTech Connect (OSTI)

    Sedano, Richard; Selecky, James; Iverson, Kathryn; Al-Jabir, Ali

    2014-02-01

    Improvements in technology, low natural gas prices, and more flexible and positive attitudes in government and utilities are making distributed generation more viable. With more distributed generation, notably combined heat and power, comes an increase in the importance of standby rates, the cost of services utilities provide when customer generation is not operating or is insufficient to meet full load. This work looks at existing utility standby tariffs in five states. It uses these existing rates and terms to showcase practices that demonstrate a sound application of regulatory principles and ones that do not. The paper also addresses areas for improvement in standby rates.

  13. Selection, Evaluation, And Rating of Compact Heat exchangers

    Energy Science and Technology Software Center (OSTI)

    2014-10-07

    SEARCH determines and optimizes the design of a compact heat exchanger for specified process conditions. The user specifies process boundary conditions including the fluid state and flow rate and SEARCH will determine the optimum flow arrangement, channel geometry, and mechanical design for the unit. Fluids are modeled using NUST Refprop or tabulated values. A variety of thermal-hydraulic correlations are available including user-defined equations to accurately capture the heat transfer and pressure drop behavior of themore » process flows.« less

  14. Cloud Properties and Radiative Heating Rates for TWP

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Comstock, Jennifer

    A cloud properties and radiative heating rates dataset is presented where cloud properties retrieved using lidar and radar observations are input into a radiative transfer model to compute radiative fluxes and heating rates at three ARM sites located in the Tropical Western Pacific (TWP) region. The cloud properties retrieval is a conditional retrieval that applies various retrieval techniques depending on the available data, that is if lidar, radar or both instruments detect cloud. This Combined Remote Sensor Retrieval Algorithm (CombRet) produces vertical profiles of liquid or ice water content (LWC or IWC), droplet effective radius (re), ice crystal generalized effective size (Dge), cloud phase, and cloud boundaries. The algorithm was compared with 3 other independent algorithms to help estimate the uncertainty in the cloud properties, fluxes, and heating rates (Comstock et al. 2013). The dataset is provided at 2 min temporal and 90 m vertical resolution. The current dataset is applied to time periods when the MMCR (Millimeter Cloud Radar) version of the ARSCL (Active Remotely-Sensed Cloud Locations) Value Added Product (VAP) is available. The MERGESONDE VAP is utilized where temperature and humidity profiles are required. Future additions to this dataset will utilize the new KAZR instrument and its associated VAPs.

  15. Cloud Properties and Radiative Heating Rates for TWP

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Comstock, Jennifer

    2013-11-07

    A cloud properties and radiative heating rates dataset is presented where cloud properties retrieved using lidar and radar observations are input into a radiative transfer model to compute radiative fluxes and heating rates at three ARM sites located in the Tropical Western Pacific (TWP) region. The cloud properties retrieval is a conditional retrieval that applies various retrieval techniques depending on the available data, that is if lidar, radar or both instruments detect cloud. This Combined Remote Sensor Retrieval Algorithm (CombRet) produces vertical profiles of liquid or ice water content (LWC or IWC), droplet effective radius (re), ice crystal generalized effective size (Dge), cloud phase, and cloud boundaries. The algorithm was compared with 3 other independent algorithms to help estimate the uncertainty in the cloud properties, fluxes, and heating rates (Comstock et al. 2013). The dataset is provided at 2 min temporal and 90 m vertical resolution. The current dataset is applied to time periods when the MMCR (Millimeter Cloud Radar) version of the ARSCL (Active Remotely-Sensed Cloud Locations) Value Added Product (VAP) is available. The MERGESONDE VAP is utilized where temperature and humidity profiles are required. Future additions to this dataset will utilize the new KAZR instrument and its associated VAPs.

  16. Diagnosis system to improve heat rate in fossil power plants

    SciTech Connect (OSTI)

    Arroyo-Figueroa, G.; Villavicencio R., A.

    1996-05-01

    Today fossil fuel power plants is showing a trend toward full automation. This increases the difficulty for human operators to follow in detail the progress of power plants, and also limit the contribution of human operators to diagnostic task. Therefore, automated and intelligent fault diagnostic systems have been intensively investigated. Despite several successful examples of diagnostic systems, often called expert systems, the development task of a diagnostic system still remains empiric and is unique for each system. This paper discusses the design of a Diagnostic System to improve Heat Rate for fossil fuel power plant. The approach is characterized as an fault tree diagnostic system. The prototype of this system has showed the benefits and the feasibility of using this system to diagnose equipment in power plants.

  17. Minimally allowed neutrinoless double beta decay rates from approximate flavor symmetries

    SciTech Connect (OSTI)

    Jenkins, James [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States) and Northwestern University, Department of Physics and Astronomy, Evanston, Illinois 60208 (United States)

    2009-06-01

    Neutrinoless double beta decay ({beta}{beta}0{nu}) is among the only realistic probes of Majorana neutrinos. In the standard scenario, dominated by light neutrino exchange, the process amplitude is proportional to m{sub ee}, the e-e element of the Majorana mass matrix. Naively, current data allow for vanishing m{sub ee}, but this should be protected by an appropriate flavor symmetry. All such symmetries lead to mass matrices inconsistent with oscillation phenomenology. I perform a spurion analysis to break all possible Abelian symmetries that guarantee vanishing {beta}{beta}0{nu} rates and search for minimally allowed values. I survey 230 broken structures to yield m{sub ee} values and current phenomenological constraints under a variety of scenarios. This analysis also extracts predictions for both neutrino oscillation parameters and kinematic quantities. Assuming reasonable tuning levels, I find that m{sub ee}>4x10{sup -6} eV at 99% confidence. Bounds below this value might indicate the Dirac neutrino nature or the existence of new light (eV-MeV scale) degrees of freedom that can potentially be probed elsewhere.

  18. Minimally allowed beta beata 0_nu rates from approximate flavor symmetries

    SciTech Connect (OSTI)

    Jenkins, James [Los Alamos National Laboratory

    2008-01-01

    Neutrinoless double beta decay ({beta}{beta}0{nu}) is the only realistic probe of Majorana neutrinos. In the standard scenario, dominated by light neutrino exchange, the process amplitude is proportional to m{sub ee} , the e - e element of the Majorana mass matrix. This is expected to hold true for small {beta}{beta}{nu} rates ({Gamma}{sub {beta}{beta}0{nu}}), even in the presence of new physics. Naively, current data allows for vanishing m{sub ee} , but this should be protected by an appropriate flavor symmetry. All such symmetries lead to mass matrices inconsistent with oscillation phenomenology. Hence, Majorana neutrinos imply nonzero {Gamma}{sub {beta}{beta}0{nu}}. I perform a spurion analysis to break all possible abelian symmetries that guarantee {Gamma}{sub {beta}{beta}0{nu}} = 0 and search for minimally allowed m{sub ee} values. Specifically, I survey 259 broken structures to yield m{sub ee} values and current phenomenological constraints under a variety of scenarios. This analysis also extracts predictions for both neutrino oscillation parameters and kinematic quantities. Assuming reasonable tuning levels, I find that m{sub ee} > 4 x 10{sup -6} eV at 99% confidence. Bounds below this value would indicate the Dirac neutrino nature or the existence of new light (eV-MeV scale) degrees of freedom that can potentially be probed elsewhere. This limit can be raised by improvements in neutrino parameter measurements, particularly of the reactor mixing angle, depending on the best fit parameter values. Such improvements will also significantly constrain the available model space and aid in future constructions.

  19. Broadband Heating Rate Profile Project (BBHRP) - SGP 1bbhrpripbe1mcfarlane

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Riihimaki, Laura; Shippert, Timothy

    2014-11-05

    The objective of the ARM Broadband Heating Rate Profile (BBHRP) Project is to provide a structure for the comprehensive assessment of our ability to model atmospheric radiative transfer for all conditions. Required inputs to BBHRP include surface albedo and profiles of atmospheric state (temperature, humidity), gas concentrations, aerosol properties, and cloud properties. In the past year, the Radiatively Important Parameters Best Estimate (RIPBE) VAP was developed to combine all of the input properties needed for BBHRP into a single gridded input file. Additionally, an interface between the RIPBE input file and the RRTM was developed using the new ARM integrated software development environment (ISDE) and effort was put into developing quality control (qc) flags and provenance information on the BBHRP output files so that analysis of the output would be more straightforward. This new version of BBHRP, sgp1bbhrpripbeC1.c1, uses the RIPBE files as input to RRTM, and calculates broadband SW and LW fluxes and heating rates at 1-min resolution using the independent column approximation. The vertical resolution is 45 m in the lower and middle troposphere to match the input cloud properties, but is at coarser resolution in the upper atmosphere. Unlike previous versions, the vertical grid is the same for both clear-sky and cloudy-sky calculations.

  20. In-Cylinder Mechanisms of PCI Heat-Release Rate Control by Fuel Reactivity

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Stratification | Department of Energy Mechanisms of PCI Heat-Release Rate Control by Fuel Reactivity Stratification In-Cylinder Mechanisms of PCI Heat-Release Rate Control by Fuel Reactivity Stratification Explores in-cylinder mechanisms by which fuel reactivity stratification via a two fuel system affects premixed charge compression ignition heat release rate to achieve diesel-like efficiency deer11_kokjohn.pdf (3.98 MB) More Documents & Publications Heavy-Duty Low-Temperature and

  1. Heating from free-free absorption and the mass-loss rate of the progenitor stars to supernovae

    SciTech Connect (OSTI)

    Björnsson, C.-I.; Lundqvist, P. E-mail: peter@astro.su.se

    2014-06-01

    An accurate determination of the mass-loss rate of the progenitor stars to core-collapse supernovae is often limited by uncertainties pertaining to various model assumptions. It is shown that under conditions when the temperature of the circumstellar medium is set by heating due to free-free absorption, observations of the accompanying free-free optical depth allow a direct determination of the mass-loss rate from observed quantities in a rather model-independent way. The temperature is determined self-consistently, which results in a characteristic time dependence of the free-free optical depth. This can be used to distinguish free-free heating from other heating mechanisms. Since the importance of free-free heating is quite model dependent, this also makes possible several consistency checks of the deduced mass-loss rate. It is argued that the free-free absorption observed in SN 1993J is consistent with heating from free-free absorption. The deduced mass-loss rate of the progenitor star is, approximately, 10{sup –5} M {sub ☉} yr{sup –1} for a wind velocity of 10 km s{sup –1}.

  2. ARM - PI Product - Cloud Properties and Radiative Heating Rates for TWP

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ProductsCloud Properties and Radiative Heating Rates for TWP ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Cloud Properties and Radiative Heating Rates for TWP A cloud properties and radiative heating rates dataset is presented where cloud properties retrieved using lidar and radar observations are input into a radiative transfer model to compute radiative fluxes and heating rates at three ARM sites

  3. Analysis of Heat Rate Improvement Potential at Coal-Fired Power...

    U.S. Energy Information Administration (EIA) Indexed Site

    Analysis of Heat Rate Improvement Potential at Coal-Fired Power Plants Release date: May 19, ... can vary depending in part on the type of equipment installed at a generating plant. ...

  4. Heat-Rate Improvement Obtained by Retubing Power-Plant Condenser Enhanced Tubes

    Energy Science and Technology Software Center (OSTI)

    1994-01-21

    A utility will only retube a condenser with enhanced tubes if the incremental cost of the enhanced tubes can be offset with reduced fuel costs. The reduced fuel cost is obtained for some units because of the higher heat-transfer coefficient of enhanced tubes. They lead to improved condenser performance measured by a lower condenser pressure and therefore a more efficient power plant. However, the higher haet-transfer coefficients do not always guarantee that enhanced tubes willmore » be more cost effective. Other issues must be considered such as the cooling-water flow reduction due to the increased pressure drop, the low-pressure turbine heat-rate variation with backpressure, and the cooling-water pump and system characteristics. These and other parameters must be considered to calculate the efficiency improvement of the power plant as commonly measured by the quantity known as the heat rate. Knowing the heat-rate improvement, the fuel cost, and the incremental increase of the enhanced tubes from the supplier, the payback time can be determined. This program calculates the heat-rate improvement that can be obtained by retubing a power plant condenser with enhanced tubes of a particular type called Korodense LPD made by Wolverine Tube, Inc. The fuel savings are easily established knowing the heat-rate improvement. All electrical utilities are potential users because a condenser is used as the heat sink for every power plant.« less

  5. An analysis of representative heating load lines for residential HSPF ratings

    SciTech Connect (OSTI)

    Rice, C. Keith; Shen, Bo; Shrestha, Som S.

    2015-07-01

    This report describes an analysis to investigate representative heating loads for single-family detached homes using current EnergyPlus simulations (DOE 2014a). Hourly delivered load results are used to determine binned load lines using US Department of Energy (DOE) residential prototype building models (DOE 2014b) developed by Pacific Northwest National Laboratory (PNNL). The selected residential single-family prototype buildings are based on the 2006 International Energy Conservation Code (IECC 2006) in the DOE climate regions. The resulting load lines are compared with the American National Standards Institute (ANSI)/Air-Conditioning, Heating, and Refrigeration Institute (AHRI) Standard 210/240 (AHRI 2008) minimum and maximum design heating requirement (DHR) load lines of the heating seasonal performance factor (HSPF) ratings procedure for each region. The results indicate that a heating load line closer to the maximum DHR load line, and with a lower zero load ambient temperature, is more representative of heating loads predicted for EnergyPlus prototype residential buildings than the minimum DHR load line presently used to determine HSPF ratings. An alternative heating load line equation was developed and compared to binned load lines obtained from the EnergyPlus simulation results. The effect on HSPF of the alternative heating load line was evaluated for single-speed and two-capacity heat pumps, and an average HSPF reduction of 16% was found. The alternative heating load line relationship is tied to the rated cooling capacity of the heat pump based on EnergyPlus autosizing, which is more representative of the house load characteristics than the rated heating capacity. The alternative heating load line equation was found to be independent of climate for the six DOE climate regions investigated, provided an adjustable zero load ambient temperature is used. For Region IV, the default DOE climate region used for HSPF ratings, the higher load line results in an ~28

  6. The Effect of Heat Treatments and Coatings on the Outgassing Rate of Stainless Steel Chambers

    SciTech Connect (OSTI)

    Mamum, Md Abdullah A.; Elmustafa, Abdelmageed A,; Stutzman, Marcy L.; Adderley, Philip A.; Poelker, Matthew

    2014-03-01

    The outgassing rates of four nominally identical 304L stainless steel vacuum chambers were measured to determine the effect of chamber coatings and heat treatments. One chamber was coated with titanium nitride (TiN) and one with amorphous silicon (a-Si) immediately following fabrication. One chamber remained uncoated throughout, and the last chamber was first tested without any coating, and then coated with a-Si following a series of heat treatments. The outgassing rate of each chamber was measured at room temperatures between 15 and 30 deg C following bakes at temperatures between 90 and 400 deg C. Measurements for bare steel showed a significant reduction in the outgassing rate by more than a factor of 20 after a 400 deg C heat treatment (3.5 x 10{sup 12} TorrL s{sup -1}cm{sup -2} prior to heat treatment, reduced to 1.7 x 10{ sup -13} TorrL s{sup -1}cm{sup -2} following heat treatment). The chambers that were coated with a-Si showed minimal change in outgassing rates with heat treatment, though an outgassing rate reduced by heat treatments prior to a-Si coating was successfully preserved throughout a series of bakes. The TiN coated chamber exhibited remarkably low outgassing rates, up to four orders of magnitude lower than the uncoated stainless steel. An evaluation of coating composition suggests the presence of elemental titanium which could provide pumping and lead to an artificially low outgassing rate. The outgassing results are discussed in terms of diffusion-limited versus recombination-limited processes.

  7. Microbase Cloud Products and Associated Heating Rates in the Tropical Western Pacific

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Microbase Cloud Products and Associated Heating Rates in the Tropical Western Pacific J. H. Mather and S. A. McFarlane Pacific Northwest National Laboratory Richland, Washington Introduction The microbase value added product (Miller et al. 2003) provides a standardized framework for calculating and storing continuous retrievals of cloud microphysical properties including liquid water content (LWC), ice water content (IWC), and cloud droplet size. Microbase is part of the larger broadband heating

  8. Kinetics of silicide formation over a wide range of heating rates spanning six orders of magnitude

    SciTech Connect (OSTI)

    Molina-Ruiz, Manel; Lopeanda, Aitor F.; Gonzalez-Silveira, Marta; Garcia, Gemma; Clavaguera-Mora, Maria T. [Grup de Nanomaterials i Microsistemes, Departament de Fsica, Universitat Autnoma de Barcelona, 08193 Bellaterra (Spain); Peral, Inma [ALBA Synchrotron Light Facility, 08290 Cerdanyola del Valls (Spain); Rodrguez-Viejo, Javier, E-mail: javier.rodriguez@uab.cat [Grup de Nanomaterials i Microsistemes, Departament de Fsica, Universitat Autnoma de Barcelona, 08193 Bellaterra (Spain); MATGAS Research Centre, UAB Campus, 08193 Bellaterra (Spain)

    2014-07-07

    Kinetic processes involving intermediate phase formation are often assumed to follow an Arrhenius temperature dependence. This behavior is usually inferred from limited data over narrow temperature intervals, where the exponential dependence is generally fully satisfied. However, direct evidence over wide temperature intervals is experimentally challenging and data are scarce. Here, we report a study of silicide formation between a 12?nm film of palladium and 15?nm of amorphous silicon in a wide range of heating rates, spanning six orders of magnitude, from 0.1 to 10{sup 5?}K/s, or equivalently more than 300?K of variation in reaction temperature. The calorimetric traces exhibit several distinct exothermic events related to interdiffusion, nucleation of Pd{sub 2}Si, crystallization of amorphous silicon, and vertical growth of Pd{sub 2}Si. Interestingly, the thickness of the initial nucleation layer depends on the heating rate revealing enhanced mass diffusion at the fastest heating rates during the initial stages of the reaction. In spite of this, the formation of the silicide strictly follows an Arrhenius temperature dependence over the whole temperature interval explored. A kinetic model is used to fit the calorimetric data over the complete heating rate range. Calorimetry is complemented by structural analysis through transmission electron microscopy and both standard and in-situ synchrotron X-ray diffraction.

  9. ITER Generic Diagnostic Upper Port Plug Nuclear Heating and Personnel Dose Rate Assesment

    SciTech Connect (OSTI)

    Russell E. Feder and Mahmoud Z. Youssef

    2009-01-28

    Neutronics analysis to find nuclear heating rates and personnel dose rates were conducted in support of the integration of diagnostics in to the ITER Upper Port Plugs. Simplified shielding models of the Visible-Infrared diagnostic and of a large aperture diagnostic were incorporated in to the ITER global CAD model. Results for these systems are representative of typical designs with maximum shielding and a small aperture (Vis-IR) and minimal shielding with a large aperture. The neutronics discrete-ordinates code ATTILA and SEVERIAN (the ATTILA parallel processing version) was used. Material properties and the 500 MW D-T volume source were taken from the ITER Brand Model MCNP benchmark model. A biased quadrature set equivelant to Sn=32 and a scattering degree of Pn=3 were used along with a 46-neutron and 21-gamma FENDL energy subgrouping. Total nuclear heating (neutron plug gamma heating) in the upper port plugs ranged between 380 and 350 kW for the Vis-IR and Large Aperture cases. The Large Aperture model exhibited lower total heating but much higher peak volumetric heating on the upper port plug structure. Personnel dose rates are calculated in a three step process involving a neutron-only transport calculation, the generation of activation volume sources at pre-defined time steps and finally gamma transport analyses are run for selected time steps. ANSI-ANS 6.1.1 1977 Flux-to-Dose conversion factors were used. Dose rates were evaluated for 1 full year of 500 MW DT operation which is comprised of 3000 1800-second pulses. After one year the machine is shut down for maintenance and personnel are permitted to access the diagnostic interspace after 2-weeks if dose rates are below 100 ?Sv/hr. Dose rates in the Visible-IR diagnostic model after one day of shutdown were 130 ?Sv/hr but fell below the limit to 90 ?Sv/hr 2-weeks later. The Large Aperture style shielding model exhibited higher and more persistent dose rates. After 1-day the dose rate was 230 ?Sv/hr but

  10. Recent Developments on the Broadband Heating Rate Profile Value-Added Product

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Recent Developments on the Broadband Heating Rate Profile Value-Added Product E. J. Mlawer, J. S. Delamere, and S. A. Clough Atmospheric and Environmental Research, Inc. Cambridge, Massachusetts M. A. Miller and K. L. Johnson Brookhaven National Laboratory Upton, New York T. R. Shippert and C. N. Long Pacific Northwest National Laboratory Richland, Washington R. G. Ellingson Florida State University Tallahassee, Florida M. H. Zhang State University of New York - Stony Brook Albany, New York R.

  11. Thermophysical properties of the Zr-0.01 Nb alloy at various heating rates and repeated cycles of heating-cooling

    SciTech Connect (OSTI)

    Petrova, I.I.; Peletsky, V.E.; Samsonov, B.N.

    1999-07-01

    The results of an experimental study of the heat capacity, enthalpy, electrical resistivity, and spectral emissivity (for the wavelength of 0.65 {micro}m) of the Zr-0.01 Nb alloy in the temperature range from 900 to 2,000 K are presented. The study was carried out using subsecond pulse heating of the samples by passing electrical current through them. Experiments were conducted at different heating rates (10{sup 3} to 10{sup 4} K {center{underscore}dot} s {sup minus}{sup 1}) and a series of experiments consisted of several cycles of pulse heating and subsequent cooling. The effect of these parameters on the temperature dependence of thermophysical properties in the region of the {alpha}-{beta} transition was studied. With an increase in the heating rate, the temperature of the {alpha}-{beta} transition, and the maximum in the heat capacity shifted to higher temperatures. There are significant differences in properties over the temperature range of the {alpha}-{beta} transition for the various heating cycles.

  12. Building America Expert Meeting: Exploring the Disconnect Between Rated and Field Performance of Water Heating Systems

    Broader source: Energy.gov [DOE]

    Water heating represents a major residential energy end use, especially in highly efficient homes where space conditioning loads and energy use has been significantly reduced. Future efforts to reduce water heating energy use requires the development of an improved understanding of equipment performance, as well as recognizing system interactions related to the distribution system and the fixture use characteristics. By bringing together a group of water heating experts, we hope to advance the shared knowledge on key water heating performance issues and identify additional data needs that will further this critical research area.

  13. SISGR - In situ characterization and modeling of formation reactions under extreme heating rates in nanostructured multilayer foils

    SciTech Connect (OSTI)

    Hufnagel, Todd C.

    2014-06-09

    Materials subjected to extreme conditions, such as very rapid heating, behave differently than materials under more ordinary conditions. In this program we examined the effect of rapid heating on solid-state chemical reactions in metallic materials. One primary goal was to develop experimental techniques capable of observing these reactions, which can occur at heating rates in excess of one million degrees Celsius per second. One approach that we used is x-ray diffraction performed using microfocused x-ray beams and very fast x-ray detectors. A second approach is the use of a pulsed electron source for dynamic transmission electron microscopy. With these techniques we were able to observe how the heating rate affects the chemical reaction, from which we were able to discern general principles about how these reactions proceed. A second thrust of this program was to develop computational tools to help us understand and predict the reactions. From atomic-scale simulations were learned about the interdiffusion between different metals at high heating rates, and about how new crystalline phases form. A second class of computational models allow us to predict the shape of the reaction front that occurs in these materials, and to connect our understanding of interdiffusion from the atomistic simulations to measurements made in the laboratory. Both the experimental and computational techniques developed in this program are expected to be broadly applicable to a wider range of scientific problems than the intermetallic solid-state reactions studied here. For example, we have already begun using the x-ray techniques to study how materials respond to mechanical deformation at very high rates.

  14. Method and apparatus for active control of combustion rate through modulation of heat transfer from the combustion chamber wall

    DOE Patents [OSTI]

    Roberts, Jr., Charles E.; Chadwell, Christopher J.

    2004-09-21

    The flame propagation rate resulting from a combustion event in the combustion chamber of an internal combustion engine is controlled by modulation of the heat transfer from the combustion flame to the combustion chamber walls. In one embodiment, heat transfer from the combustion flame to the combustion chamber walls is mechanically modulated by a movable member that is inserted into, or withdrawn from, the combustion chamber thereby changing the shape of the combustion chamber and the combustion chamber wall surface area. In another embodiment, heat transfer from the combustion flame to the combustion chamber walls is modulated by cooling the surface of a portion of the combustion chamber wall that is in close proximity to the area of the combustion chamber where flame speed control is desired.

  15. Zero-point cooling and heating-rate measurements of a single {sup 88}Sr{sup +} ion

    SciTech Connect (OSTI)

    Letchumanan, V.; Wilpers, G.; Brownnutt, M.; Gill, P.; Sinclair, A. G.

    2007-06-15

    A single {sup 88}Sr{sup +} ion has been cooled to the zero point of its axial motion in a radio frequency endcap trap. A ground-state occupation probability of 98.6(8)% was achieved using resolved sideband laser cooling on the 674 nm {sup 2}S{sub 1/2}-{sup 2}D{sub 5/2} quadrupole transition. The ion's heating rate was measured to be 0.054(4) quanta/ms, implying a spectral density of electric field noise comparable to the other reported values, summarized in the paper by Deslauriers et al. [Phys. Rev. A 70, 043048 (2004)]. Low heating rates were only observed using a trap that had minimal exposure to atomic flux.

  16. Heat

    U.S. Energy Information Administration (EIA) Indexed Site

    Release date: April 2015 Revised date: May 2016 Heat pumps Furnaces Indiv- idual space heaters District heat Boilers Pack- aged heating units Other All buildings 87,093 80,078 11,846 8,654 20,766 5,925 22,443 49,188 1,574 Building floorspace (square feet) 1,001 to 5,000 8,041 6,699 868 1,091 1,747 Q 400 3,809 Q 5,001 to 10,000 8,900 7,590 1,038 1,416 2,025 Q 734 4,622 Q 10,001 to 25,000 14,105 12,744 1,477 2,233 3,115 Q 2,008 8,246 Q 25,001 to 50,000 11,917 10,911 1,642 1,439 3,021 213 2,707

  17. Economic analysis of solar industrial process heat systems: a methodology to determine annual required revenue and internal rate of return

    SciTech Connect (OSTI)

    Dickinson, W.C.; Brown, K.C.

    1981-08-11

    To permit an economic evaluation of solar industrial process heat systems, a methodology was developed to determine the annual required revenue and the internal rate of return. First, a format is provided to estimate the solar system's installed cost, annual operating and maintenance expenses, and net annual solar energy delivered to the industrial process. Then an expression is presented that gives the annual required revenue and the price of solar energy. The economic attractiveness of the potential solar investment can be determined by comparing the price of solar energy with the price of fossil fuel, both expressed in levelized terms. This requires calculation of the internal rate of return on the solar investment or, in certain cases, the growth rate of return.

  18. Rapid heating tensile tests of hydrogen-charged high-energy-rate-forged 316L stainless steel

    SciTech Connect (OSTI)

    Mosley, W.C.

    1989-05-19

    316L stainless steel is a candidate material for construction of equipment that will be exposed to tritium. Proper design of the equipment will require an understanding of how tritium and its decay product helium affect mechanical properties. This memorandum describes results of rapid heating tensile testing of hydrogen-charged specimens of high-energy-rate-forged (HERF) 316L stainless steel. These results provide a data base for comparison with uncharged and tritium-charged-and-aged specimens to distinguish the effects of hydrogen and helium. Details of the experimental equipment and procedures and results for uncharged specimens were reported previously. 3 refs., 10 figs.

  19. The Stress Corrosion Crack Growth Rate of Alloy 600 Heat Affected Zones Exposed to High Purity Water

    SciTech Connect (OSTI)

    George A. Young; Nathan Lewis

    2003-04-05

    Grain boundary chromium carbides improve the resistance of nickel based alloys to primary water stress corrosion cracking (PWSCC). However, in weld heat affected zones (HAZ's), thermal cycles from fusion welding can solutionize beneficial grain boundary carbides, produce locally high residual stresses and strains, and promote PWSCC. The present research investigates the crack growth rate of an A600 HAZ as a function of test temperature. The A600 HAZ was fabricated by building up a gas-tungsten-arc-weld deposit of EN82H filler metal onto a mill-annealed A600 plate. Fracture mechanics based, stress corrosion crack growth rate testing was performed in high purity water between 600 F and 680 F at an initial stress intensity factor of 40 ksi {radical}in and at a constant electrochemical potential. The HAZ samples exhibited significant SCC, entirely within the HAZ at all temperatures tested. While the HAZ samples showed the same temperature dependence for SCC as the base material (HAZ: 29.8 {+-} 11.2{sub 95%} kcal/mol vs A600 Base: 35.3 {+-} 2.58{sub 95%} kcal/mol), the crack growth rates were {approx} 30X faster than the A600 base material tested at the same conditions. The increased crack growth rates of the HAZ is attributed to fewer intergranular chromium rich carbides and to increased plastic strain in the HAZ as compared to the unaffected base material.

  20. Heat Release Rates

    Broader source: Energy.gov [DOE]

    Supporting Technical Document for the Radiological Release Accident Investigation Report (Phase II Report)

  1. Research, development, and testing of a prototype two-stage low-input rate oil burner for variable output heating system applications

    SciTech Connect (OSTI)

    Krajewski, R.F.; Butcher, T.A.

    1997-09-01

    The use of a Two-Stage Fan Atomized Oil Burner (TSFAB) in space and water heating applications will have dramatic advantages in terms of it`s potential for a high Annual Fuel Utilization Efficiency (AFUE) and/or Energy Factor (EF) rating for the equipment. While demonstrations of a single rate burner in an actual application have already yielded sufficient confidence that space and domestic heating loads can be met at a single low firing rate, this represents only a narrow solution to the diverse nature of building space heating and domestic water loads that the industry must address. The mechanical development, proposed control, and testing of the Two-Stage burner is discussed in terms of near term and long term goals.

  2. ITER Generic Diagnostic Upper Port Plug Nuclear Heating and Personnel Dose Rate Assesment Neutronics Analysis using the ATTILA Discrete Ordinates Code

    SciTech Connect (OSTI)

    Russell Feder and Mahmoud Z. Yousef

    2009-05-29

    Neutronics analysis to find nuclear heating rates and personnel dose rates were conducted in support of the integration of diagnostics in to the ITER Upper Port Plugs. Simplified shielding models of the Visible-Infrared diagnostic and of the ECH heating system were incorporated in to the ITER global CAD model. Results for these systems are representative of typical designs with maximum shielding and a small aperture (Vis-IR) and minimal shielding with a large aperture (ECH). The neutronics discrete-ordinates code ATTILA and SEVERIAN (the ATTILA parallel processing version) was used. Material properties and the 500 MW D-T volume source were taken from the ITER Brand Model MCNP benchmark model. A biased quadrature set equivelant to Sn=32 and a scattering degree of Pn=3 were used along with a 46-neutron and 21-gamma FENDL energy subgrouping. Total nuclear heating (neutron plug gamma heating) in the upper port plugs ranged between 380 and 350 kW for the Vis-IR and ECH cases. The ECH or Large Aperture model exhibited lower total heating but much higher peak volumetric heating on the upper port plug structure. Personnel dose rates are calculated in a three step process involving a neutron-only transport calculation, the generation of activation volume sources at pre-defined time steps and finally gamma transport analyses are run for selected time steps. ANSI-ANS 6.1.1 1977 Flux-to-Dose conversion factors were used. Dose rates were evaluated for 1 full year of 500 MW DT operation which is comprised of 3000 1800-second pulses. After one year the machine is shut down for maintenance and personnel are permitted to access the diagnostic interspace after 2-weeks if dose rates are below 100 ?Sv/hr. Dose rates in the Visible-IR diagnostic model after one day of shutdown were 130 ?Sv/hr but fell below the limit to 90 ?Sv/hr 2-weeks later. The Large Aperture or ECH style shielding model exhibited higher and more persistent dose rates. After 1-day the dose rate was 230 ?Sv

  3. Tips: Heat Pumps | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    climates, providing up to three times more heat than the energy they use. Today's heat pump can reduce your electricity use for heating by approximately 50% compared to...

  4. Heat release characteristics of stratified-charge rotary engines

    SciTech Connect (OSTI)

    Dimpelfeld, P.; Humke, A.

    1987-01-01

    A computer program for calculating heat release rates from stratified-charge rotary engines is described. Important aspects of the program include calculation of equilibrium combustion product properties, treatment of both liquid and gas phase fuel in the chamber, heat transfer, leakage past side and apex seals, and crevice effects. Heat release rates are presented from 580 and 70 Series rotary engines. Combustion in the 580 Series engine exhibits two distinct phases. The first phase occurs rapidly, with a duration of approximately 40 shaft degrees. The second phase of combustion proceeds more slowly, with a duration of approximately 70 shaft degrees. Three phases of combustion are observed for the 70 Series engine.

  5. Vapor pressure and evaporation rate of certain heat-resistant compounds in a vacuum at high temperatures

    SciTech Connect (OSTI)

    Bolgar, A.S.; Verkhoglyadova, T.S.; Samsonov, G.V.

    1985-02-01

    The vapor pressure and evaporation rate of borides of titanium, zirconium, and chrome and of strontium and carbides of titanium, zirconium, and chrome, molybdenum silicide and nitrides of titanium, niobium, and tantalum in a vacuum were studied. It is concluded that all subject compounds evaporate by molecular structures except AlB sub 12' which dissociates, losing the aluminum.

  6. Approximate option pricing

    SciTech Connect (OSTI)

    Chalasani, P.; Saias, I.; Jha, S.

    1996-04-08

    As increasingly large volumes of sophisticated options (called derivative securities) are traded in world financial markets, determining a fair price for these options has become an important and difficult computational problem. Many valuation codes use the binomial pricing model, in which the stock price is driven by a random walk. In this model, the value of an n-period option on a stock is the expected time-discounted value of the future cash flow on an n-period stock price path. Path-dependent options are particularly difficult to value since the future cash flow depends on the entire stock price path rather than on just the final stock price. Currently such options are approximately priced by Monte carlo methods with error bounds that hold only with high probability and which are reduced by increasing the number of simulation runs. In this paper the authors show that pricing an arbitrary path-dependent option is {number_sign}-P hard. They show that certain types f path-dependent options can be valued exactly in polynomial time. Asian options are path-dependent options that are particularly hard to price, and for these they design deterministic polynomial-time approximate algorithms. They show that the value of a perpetual American put option (which can be computed in constant time) is in many cases a good approximation to the value of an otherwise identical n-period American put option. In contrast to Monte Carlo methods, the algorithms have guaranteed error bounds that are polynormally small (and in some cases exponentially small) in the maturity n. For the error analysis they derive large-deviation results for random walks that may be of independent interest.

  7. Tips: Heat Pumps | Department of Energy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    electric heating, providing up to three times more heat than the energy they use. Today's heat pump can reduce your electricity use for heating by approximately 50% compared to...

  8. Evaluating temperature and fuel stratification for heat-release rate control in a reactivity-controlled compression-ignition engine using optical diagnostics and chemical kinetics modeling

    SciTech Connect (OSTI)

    Musculus, Mark P. B.; Kokjohn, Sage L.; Reitz, Rolf D.

    2015-04-23

    We investigated the combustion process in a dual-fuel, reactivity-controlled compression-ignition (RCCI) engine using a combination of optical diagnostics and chemical kinetics modeling to explain the role of equivalence ratio, temperature, and fuel reactivity stratification for heat-release rate control. An optically accessible engine is operated in the RCCI combustion mode using gasoline primary reference fuels (PRF). A well-mixed charge of iso-octane (PRF = 100) is created by injecting fuel into the engine cylinder during the intake stroke using a gasoline-type direct injector. Later in the cycle, n-heptane (PRF = 0) is delivered through a centrally mounted diesel-type common-rail injector. This injection strategy generates stratification in equivalence ratio, fuel blend, and temperature. The first part of this study uses a high-speed camera to image the injection events and record high-temperature combustion chemiluminescence. Moreover, the chemiluminescence imaging showed that, at the operating condition studied in the present work, mixtures in the squish region ignite first, and the reaction zone proceeds inward toward the center of the combustion chamber. The second part of this study investigates the charge preparation of the RCCI strategy using planar laser-induced fluorescence (PLIF) of a fuel tracer under non-reacting conditions to quantify fuel concentration distributions prior to ignition. The fuel-tracer PLIF data show that the combustion event proceeds down gradients in the n-heptane distribution. The third part of the study uses chemical kinetics modeling over a range of mixtures spanning the distributions observed from the fuel-tracer fluorescence imaging to isolate the roles of temperature, equivalence ratio, and PRF number stratification. The simulations predict that PRF number stratification is the dominant factor controlling the ignition location and growth rate of the reaction zone. Equivalence ratio has a smaller, but still significant

  9. Geothermal Heat Pump Manufacturing Activities

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    8 Geothermal heat pump shipments by origin, 2008 and 2009 (rated capacity in tons) Origin ... Administration (EIA), Form EIA-902, "Annual Geothermal Heat Pump Manufacturers Survey

  10. Geothermal Heat Pump Manufacturing Activities

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    0 Geothermal heat pump domestic shipments by customer type, 2008 and 2009 (rated capacity ... Administration (EIA), Form EIA-902, "Annual Geothermal Heat Pump Manufacturers Survey

  11. Geothermal Heat Pump Manufacturing Activities

    Gasoline and Diesel Fuel Update (EIA)

    1 Geothermal heat pump domestic shipments by sector and model type, 2009 (rated capacity ... Administration (EIA), Form EIA-902, "Annual Geothermal Heat Pump Manufacturers Survey

  12. Geothermal Heat Pump Manufacturing Activities

    Gasoline and Diesel Fuel Update (EIA)

    Rated capacity of geothermal heat pump shipments by model type, 2000 - 2009 (tons) ARI-320 ... Administration (EIA), Form EIA-902, "Annual Geothermal Heat Pump Manufacturers Survey."

  13. Development of advanced low-temperature heat transfer fluids for district heating and cooling, final report

    SciTech Connect (OSTI)

    Cho, Y.I.; Lorsch, H.G.

    1991-03-31

    The feasibility of adding phase change materials (PCMS) and surfactants to the heat transfer fluids in district cooling systems was investigated. It increases the thermal capacity of the heat transfer fluid and therefore decreases the volume that needs to be pumped. It also increases the heat transfer rate, resulting in smaller heat exchangers. The thermal behavior of two potential PCMS, hexadecane and tetradecane paraffin wax, was experimentally evaluated. The heat of fusion of these materials is approximately 60% of that of ice. They exhibit no supercooling and are stable under repeated thermal cycling. While test results for laboratory grade materials showed good agreement with data in the literature, both melting point and heat of fusion for commercial grade hexadecane were found to be considerably lower than literature values. PCM/water mixtures were tested in a laboratory-scale test loop to determine heat transfer and flow resistance properties. For 10% and 25% PCM/water slurries, the heat transfer enhancement was found to be approximately 18 and 30 percent above the value for water, respectively. Within the turbulent region, there is only a minor pumping penalty from the addition of up to 25% PCM to the water. Research is continuing on these fluids in order to determine their behavior in large-size loops and to arrive at optimum formulations.

  14. Heat exchanger

    DOE Patents [OSTI]

    Wolowodiuk, Walter

    1976-01-06

    A heat exchanger of the straight tube type in which different rates of thermal expansion between the straight tubes and the supply pipes furnishing fluid to those tubes do not result in tube failures. The supply pipes each contain a section which is of helical configuration.

  15. Approximate circuits for increased reliability

    DOE Patents [OSTI]

    Hamlet, Jason R.; Mayo, Jackson R.

    2015-08-18

    Embodiments of the invention describe a Boolean circuit having a voter circuit and a plurality of approximate circuits each based, at least in part, on a reference circuit. The approximate circuits are each to generate one or more output signals based on values of received input signals. The voter circuit is to receive the one or more output signals generated by each of the approximate circuits, and is to output one or more signals corresponding to a majority value of the received signals. At least some of the approximate circuits are to generate an output value different than the reference circuit for one or more input signal values; however, for each possible input signal value, the majority values of the one or more output signals generated by the approximate circuits and received by the voter circuit correspond to output signal result values of the reference circuit.

  16. Approximate circuits for increased reliability

    DOE Patents [OSTI]

    Hamlet, Jason R.; Mayo, Jackson R.

    2015-12-22

    Embodiments of the invention describe a Boolean circuit having a voter circuit and a plurality of approximate circuits each based, at least in part, on a reference circuit. The approximate circuits are each to generate one or more output signals based on values of received input signals. The voter circuit is to receive the one or more output signals generated by each of the approximate circuits, and is to output one or more signals corresponding to a majority value of the received signals. At least some of the approximate circuits are to generate an output value different than the reference circuit for one or more input signal values; however, for each possible input signal value, the majority values of the one or more output signals generated by the approximate circuits and received by the voter circuit correspond to output signal result values of the reference circuit.

  17. Compare All CBECS Activities: District Heat Use

    U.S. Energy Information Administration (EIA) Indexed Site

    District Heat Use Compare Activities by ... District Heat Use Total District Heat Consumption by Building Type Commercial buildings in the U.S. used a total of approximately 433...

  18. Evaluating temperature and fuel stratification for heat-release rate control in a reactivity-controlled compression-ignition engine using optical diagnostics and chemical kinetics modeling

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Musculus, Mark P. B.; Kokjohn, Sage L.; Reitz, Rolf D.

    2015-04-23

    We investigated the combustion process in a dual-fuel, reactivity-controlled compression-ignition (RCCI) engine using a combination of optical diagnostics and chemical kinetics modeling to explain the role of equivalence ratio, temperature, and fuel reactivity stratification for heat-release rate control. An optically accessible engine is operated in the RCCI combustion mode using gasoline primary reference fuels (PRF). A well-mixed charge of iso-octane (PRF = 100) is created by injecting fuel into the engine cylinder during the intake stroke using a gasoline-type direct injector. Later in the cycle, n-heptane (PRF = 0) is delivered through a centrally mounted diesel-type common-rail injector. This injectionmore » strategy generates stratification in equivalence ratio, fuel blend, and temperature. The first part of this study uses a high-speed camera to image the injection events and record high-temperature combustion chemiluminescence. Moreover, the chemiluminescence imaging showed that, at the operating condition studied in the present work, mixtures in the squish region ignite first, and the reaction zone proceeds inward toward the center of the combustion chamber. The second part of this study investigates the charge preparation of the RCCI strategy using planar laser-induced fluorescence (PLIF) of a fuel tracer under non-reacting conditions to quantify fuel concentration distributions prior to ignition. The fuel-tracer PLIF data show that the combustion event proceeds down gradients in the n-heptane distribution. The third part of the study uses chemical kinetics modeling over a range of mixtures spanning the distributions observed from the fuel-tracer fluorescence imaging to isolate the roles of temperature, equivalence ratio, and PRF number stratification. The simulations predict that PRF number stratification is the dominant factor controlling the ignition location and growth rate of the reaction zone. Equivalence ratio has a smaller, but still

  19. Miniature heat pumps for portable and distributed space conditioning applications

    SciTech Connect (OSTI)

    Drost, M.K.; Friedrich, M.

    1997-12-31

    The Pacific Northwest National Laboratory (PNNL) is developing a miniature absorption heat pump for a range of microclimate control applications, including manportable cooling and distributed space conditioning. The miniature absorption heat pump will be sized to provide 350 W cooling, will have dimensions of 9 cm x 9 cm x 6 cm, and will weigh approximately 0.65 kg. Compared to a macroscale absorption heat pump, this represents reduction in volume by a factor of 60. A complete manportable cooling system including the heat pump, an air-cooled heat exchanger, batteries, and fuel is estimated to weight between 4 and 5 kg, compared to the 10 kg weight of alternative systems. Size and weight reductions are obtained by developing a device that can simultaneously take advantage of the high heat and mass transfer rates attainable in microscale structures while being large enough to allow electric powered pumping.

  20. Explicit approximations to estimate the perturbative diffusivity in the presence of convectivity and damping. I. Semi-infinite slab approximations

    SciTech Connect (OSTI)

    Berkel, M. van; Zwart, H. J.; Tamura, N.; Ida, K.; Hogeweij, G. M. D.; Inagaki, S.; Baar, M. R. de

    2014-11-15

    In this paper, a number of new approximations are introduced to estimate the perturbative diffusivity (χ), convectivity (V), and damping (τ) in cylindrical geometry. For this purpose, the harmonic components of heat waves induced by localized deposition of modulated power are used. The approximations are based on semi-infinite slab approximations of the heat equation. The main result is the approximation of χ under the influence of V and τ based on the phase of two harmonics making the estimate less sensitive to calibration errors. To understand why the slab approximations can estimate χ well in cylindrical geometry, the relationships between heat transport models in slab and cylindrical geometry are studied. In addition, the relationship between amplitude and phase with respect to their derivatives, used to estimate χ, is discussed. The results are presented in terms of the relative error for the different derived approximations for different values of frequency, transport coefficients, and dimensionless radius. The approximations show a significant region in which χ, V, and τ can be estimated well, but also regions in which the error is large. Also, it is shown that some compensation is necessary to estimate V and τ in a cylindrical geometry. On the other hand, errors resulting from the simplified assumptions are also discussed showing that estimating realistic values for V and τ based on infinite domains will be difficult in practice. This paper is the first part (Part I) of a series of three papers. In Part II and Part III, cylindrical approximations based directly on semi-infinite cylindrical domain (outward propagating heat pulses) and inward propagating heat pulses in a cylindrical domain, respectively, will be treated.

  1. Heat pipe array heat exchanger

    DOE Patents [OSTI]

    Reimann, Robert C.

    1987-08-25

    A heat pipe arrangement for exchanging heat between two different temperature fluids. The heat pipe arrangement is in a ounterflow relationship to increase the efficiency of the coupling of the heat from a heat source to a heat sink.

  2. Approximate Model for Turbulent Stagnation Point Flow.

    SciTech Connect (OSTI)

    Dechant, Lawrence

    2016-01-01

    Here we derive an approximate turbulent self-similar model for a class of favorable pressure gradient wedge-like flows, focusing on the stagnation point limit. While the self-similar model provides a useful gross flow field estimate this approach must be combined with a near wall model is to determine skin friction and by Reynolds analogy the heat transfer coefficient. The combined approach is developed in detail for the stagnation point flow problem where turbulent skin friction and Nusselt number results are obtained. Comparison to the classical Van Driest (1958) result suggests overall reasonable agreement. Though the model is only valid near the stagnation region of cylinders and spheres it nonetheless provides a reasonable model for overall cylinder and sphere heat transfer. The enhancement effect of free stream turbulence upon the laminar flow is used to derive a similar expression which is valid for turbulent flow. Examination of free stream enhanced laminar flow suggests that the rather than enhancement of a laminar flow behavior free stream disturbance results in early transition to turbulent stagnation point behavior. Excellent agreement is shown between enhanced laminar flow and turbulent flow behavior for high levels, e.g. 5% of free stream turbulence. Finally the blunt body turbulent stagnation results are shown to provide realistic heat transfer results for turbulent jet impingement problems.

  3. Explicit approximations to estimate the perturbative diffusivity in the presence of convectivity and damping. II. Semi-infinite cylindrical approximations

    SciTech Connect (OSTI)

    Berkel, M. van; Hogeweij, G. M. D.; Tamura, N.; Ida, K.; Zwart, H. J.; Inagaki, S.; Baar, M. R. de

    2014-11-15

    In this paper, a number of new explicit approximations are introduced to estimate the perturbative diffusivity (χ), convectivity (V), and damping (τ) in a cylindrical geometry. For this purpose, the harmonic components of heat waves induced by localized deposition of modulated power are used. The approximations are based upon the heat equation in a semi-infinite cylindrical domain. The approximations are based upon continued fractions, asymptotic expansions, and multiple harmonics. The relative error for the different derived approximations is presented for different values of frequency, transport coefficients, and dimensionless radius. Moreover, it is shown how combinations of different explicit formulas can yield good approximations over a wide parameter space for different cases, such as no convection and damping, only damping, and both convection and damping. This paper is the second part (Part II) of a series of three papers. In Part I, the semi-infinite slab approximations have been treated. In Part III, cylindrical approximations are treated for heat waves traveling towards the center of the plasma.

  4. Plasma Physics Approximations in Ares

    SciTech Connect (OSTI)

    Managan, R. A.

    2015-01-08

    Lee & More derived analytic forms for the transport properties of a plasma. Many hydro-codes use their formulae for electrical and thermal conductivity. The coefficients are complex functions of Fermi-Dirac integrals, Fn( μ/θ ), the chemical potential, μ or ζ = ln(1+e μ/θ ), and the temperature, θ = kT. Since these formulae are expensive to compute, rational function approximations were fit to them. Approximations are also used to find the chemical potential, either μ or ζ . The fits use ζ as the independent variable instead of μ/θ . New fits are provided for Aα (ζ ),Aβ (ζ ), ζ, f(ζ ) = (1 + e-μ/θ)F1/2(μ/θ), F1/2'/F1/2, Fcα, and Fcβ. In each case the relative error of the fit is minimized since the functions can vary by many orders of magnitude. The new fits are designed to exactly preserve the limiting values in the non-degenerate and highly degenerate limits or as ζ→ 0 or ∞. The original fits due to Lee & More and George Zimmerman are presented for comparison.

  5. Home Heating

    Broader source: Energy.gov [DOE]

    Your choice of heating technologies impacts your energy bill. Learn about the different options for heating your home.

  6. Geothermal District Heating Economics

    Energy Science and Technology Software Center (OSTI)

    1995-07-12

    GEOCITY is a large-scale simulation model which combines both engineering and economic submodels to systematically calculate the cost of geothermal district heating systems for space heating, hot-water heating, and process heating based upon hydrothermal geothermal resources. The GEOCITY program simulates the entire production, distribution, and waste disposal process for geothermal district heating systems, but does not include the cost of radiators, convectors, or other in-house heating systems. GEOCITY calculates the cost of district heating basedmore » on the climate, population, and heat demand of the district; characteristics of the geothermal resource and distance from the distribution center; well-drilling costs; design of the distribution system; tax rates; and financial conditions.« less

  7. Expert Meeting Report: Exploring the Disconnect Between Rated...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Exploring the Disconnect Between Rated and Field Performance of Water Heating Systems M. ... Between Rated and Field Performance of Water Heating Systems Prepared for: The National ...

  8. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard

    1980-01-01

    A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer. The heat pump part of the system heats or cools a house or other structure through a combination of evaporation and absorption or, conversely, condensation and desorption, in a pair of containers. A set of automatic controls change the system for operation during winter and summer months and for daytime and nighttime operation to satisfactorily heat and cool a house during an entire year. The absorber chamber is subjected to solar heating during regeneration cycles and is covered by one or more layers of glass or other transparent material. Daytime home air used for heating the home is passed at appropriate flow rates between the absorber container and the first transparent cover layer in heat transfer relationship in a manner that greatly reduce eddies and resultant heat loss from the absorbant surface to ambient atmosphere.

  9. An approximation technique for jet impingement flow

    SciTech Connect (OSTI)

    Najafi, Mahmoud; Fincher, Donald; Rahni, Taeibi; Javadi, KH.; Massah, H.

    2015-03-10

    The analytical approximate solution of a non-linear jet impingement flow model will be demonstrated. We will show that this is an improvement over the series approximation obtained via the Adomian decomposition method, which is itself, a powerful method for analysing non-linear differential equations. The results of these approximations will be compared to the Runge-Kutta approximation in order to demonstrate their validity.

  10. Magnetic reconnection under anisotropic magnetohydrodynamic approximation

    SciTech Connect (OSTI)

    Hirabayashi, K.; Hoshino, M.

    2013-11-15

    We study the formation of slow-mode shocks in collisionless magnetic reconnection by using one- and two-dimensional collisionless MHD codes based on the double adiabatic approximation and the Landau closure model. We bridge the gap between the Petschek-type MHD reconnection model accompanied by a pair of slow shocks and the observational evidence of the rare occasion of in-situ slow shock observations. Our results showed that once magnetic reconnection takes place, a firehose-sense (p{sub ?}>p{sub ?}) pressure anisotropy arises in the downstream region, and the generated slow shocks are quite weak comparing with those in an isotropic MHD. In spite of the weakness of the shocks, however, the resultant reconnection rate is 10%30% higher than that in an isotropic case. This result implies that the slow shock does not necessarily play an important role in the energy conversion in the reconnection system and is consistent with the satellite observation in the Earth's magnetosphere.

  11. Development of Versatile Compressor Modeling using Approximation Techniques for Alternative Refrigerants Evaluation

    SciTech Connect (OSTI)

    Abdelaziz, Omar; Shrestha, Som S

    2014-01-01

    Refrigerants are the life-blood of vapor compression systems that are widely used in Heating, Ventilation, Air-Conditioning, and Refrigeration (HVAC&R) applications. The HVAC&R community is currently transitioning from main-stream refrigerants that have high Global Warming Potential (GWP) to alternative lower-GWP refrigerants. During this transition, it is important to account for the life cycle climate performance of alternative refrigerants since their performance will be different than that of higher-GWP refrigerants. This requires the evaluation of the system performance with the new refrigerants. Unfortunately, it is extremely difficult to predict the realistic performance of new alternative refrigerants without experimental validation. One of the main challenges in this regard is modeling the compressor performance with high fidelity due to the complex interaction of operating parameters, geometry, boundary conditions, and fluid properties. High fidelity compressor models are computationally expensive and require significant pre-processing to evaluate the performance of alternative refrigerants. This paper presents a new approach to modeling compressor performance when alternative refrigerants are used. The new modeling concept relies on using existing compressor performance to create an approximate model that captures the dependence of compressor performance on key operating parameters and fluid properties. The model can be built using a myriad of approximation techniques. This paper focuses on Kriging-based techniques to develop higher fidelity approximate compressor models. Baseline and at least one alternative refrigerant performance data are used to build the model. The model accuracy was evaluated by comparing the model results with compressor performance data using other refrigerants. Preliminary results show that the approximate model can predict the compressor mass flow rate and power consumption within 5%.

  12. HEAT TRANSFER METHOD

    DOE Patents [OSTI]

    Gambill, W.R.; Greene, N.D.

    1960-08-30

    A method is given for increasing burn-out heat fluxes under nucleate boiling conditions in heat exchanger tubes without incurring an increase in pumping power requirements. This increase is achieved by utilizing a spinning flow having a rotational velocity sufficient to produce a centrifugal acceleration of at least 10,000 g at the tube wall. At this acceleration the heat-transfer rate at burn out is nearly twice the rate which can be achieved in a similar tube utilizing axial flow at the same pumping power. At higher accelerations the improvement over axial flow is greater, and heat fluxes in excess of 50 x 10/sup 6/ Btu/hr/sq ft can be achieved.

  13. Heat exchanger

    DOE Patents [OSTI]

    Daman, Ernest L.; McCallister, Robert A.

    1979-01-01

    A heat exchanger is provided having first and second fluid chambers for passing primary and secondary fluids. The chambers are spaced apart and have heat pipes extending from inside one chamber to inside the other chamber. A third chamber is provided for passing a purge fluid, and the heat pipe portion between the first and second chambers lies within the third chamber.

  14. The Broadband Heating Rate Profile (BBHRP) VAP

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    National Laboratory Richland, Washington R. G. Ellingson Florida State University Tallahassee, Florida M. H. Zhang State University of New York at Albany Albany, New York Stony ...

  15. Property:HeatRate | Open Energy Information

    Open Energy Info (EERE)

    Landfi Biomass Facility + 12,916.67 + Atlantic County Util Biomass Facility + 13,648 + Avon Energy Partners LLC Biomass Facility + 10,366.7 + B BJ Gas Recovery Biomass Facility +...

  16. Trigonometric Pade approximants for functions with regularly decreasing Fourier coefficients

    SciTech Connect (OSTI)

    Labych, Yuliya A; Starovoitov, Alexander P [Gomel State University, Gomel (Belarus)

    2009-08-31

    Sufficient conditions describing the regular decrease of the coefficients of a Fourier series f(x)=a{sub 0}/2 + {sigma} a{sub n} cos kx are found which ensure that the trigonometric Pade approximants {pi}{sup t}{sub n,m}(x;f) converge to the function f in the uniform norm at a rate which coincides asymptotically with the highest possible one. The results obtained are applied to problems dealing with finding sharp constants for rational approximations. Bibliography: 31 titles.

  17. Rate Information

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases Rate Information Current Power Rates Current Transmission Rates...

  18. Susanville District Heating District Heating Low Temperature...

    Open Energy Info (EERE)

    Susanville District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Susanville District Heating District Heating Low Temperature...

  19. Total Space Heating Water Heating Cook-

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    Commercial Buildings Energy Consumption Survey: Energy End-Use Consumption Tables Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing...

  20. Total Space Heating Water Heating Cook-

    Gasoline and Diesel Fuel Update (EIA)

    Released: September, 2008 Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All Buildings* ... 1,870 1,276...

  1. Total Space Heating Water Heating Cook-

    Gasoline and Diesel Fuel Update (EIA)

    Energy Consumption Survey: Energy End-Use Consumption Tables Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All...

  2. Total Space Heating Water Heating Cook-

    Gasoline and Diesel Fuel Update (EIA)

    Released: September, 2008 Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All Buildings* ... 1,602 1,397...

  3. Total Space Heating Water Heating Cook-

    Gasoline and Diesel Fuel Update (EIA)

    Released: September, 2008 Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All Buildings ... 2,037...

  4. Approximate error conjugation gradient minimization methods

    DOE Patents [OSTI]

    Kallman, Jeffrey S

    2013-05-21

    In one embodiment, a method includes selecting a subset of rays from a set of all rays to use in an error calculation for a constrained conjugate gradient minimization problem, calculating an approximate error using the subset of rays, and calculating a minimum in a conjugate gradient direction based on the approximate error. In another embodiment, a system includes a processor for executing logic, logic for selecting a subset of rays from a set of all rays to use in an error calculation for a constrained conjugate gradient minimization problem, logic for calculating an approximate error using the subset of rays, and logic for calculating a minimum in a conjugate gradient direction based on the approximate error. In other embodiments, computer program products, methods, and systems are described capable of using approximate error in constrained conjugate gradient minimization problems.

  5. Whistler turbulence heating of electrons and ions: Three-dimensional particle-in-cell simuations

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gary, S. Peter; Hughes, R. Scott; Wang, Joseph

    2016-01-14

    In this study, the decay of whistler turbulence in a collisionless, homogeneous, magnetized plasma is studied using three-dimensional particle-in-cell simulations. The simulations are initialized with a narrowband, relatively isotropic distribution of long wavelength whistler modes. A first ensemble of simulations at electron betamore » $${\\beta }_{{\\rm{e}}}$$ = 0.25 and ion-to-electron mass ratio $${m}_{{\\rm{i}}}$$/$${m}_{{\\rm{e}}}$$ = 400 is carried out on a domain cube of dimension $$L{\\omega }_{\\mathrm{pi}}$$/c = 5.12 where $${\\omega }_{\\mathrm{pi}}$$ is the ion plasma frequency. The simulations begin with a range of dimensionless fluctuating field energy densities, $${\\epsilon }_{{\\rm{o}}}$$, and follow the fluctuations as they cascade to broadband, anisotropic turbulence which dissipates at shorter wavelengths, heating both electrons and ions. The electron heating is stronger and preferentially parallel/antiparallel to the background magnetic field $${{\\boldsymbol{B}}}_{{\\rm{o}}};$$ the ion energy gain is weaker and is preferentially in directions perpendicular to $${{\\boldsymbol{B}}}_{{\\rm{o}}}$$. The important new results here are that, over 0.01 < $${\\epsilon }_{{\\rm{o}}}$$ < 0.25, the maximum rate of electron heating scales approximately as $${\\epsilon }_{{\\rm{o}}}$$, and the maximum rate of ion heating scales approximately as $${\\epsilon }_{{\\rm{o}}}^{1.5}$$. A second ensemble of simulations at $${\\epsilon }_{{\\rm{o}}}$$ = 0.10 and $${\\beta }_{{\\rm{e}}}$$ = 0.25 shows that, over 25 < $${m}_{{\\rm{i}}}$$/$${m}_{{\\rm{e}}}\\;$$< 1836, the ratio of the maximum ion heating rate to the maximum electron heating rate scales approximately as $${m}_{{\\rm{e}}}$$/$${m}_{{\\rm{i}}}$$.« less

  6. A Survey of Techniques for Approximate Computing

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Mittal, Sparsh

    2016-03-18

    Approximate computing trades off computation quality with the effort expended and as rising performance demands confront with plateauing resource budgets, approximate computing has become, not merely attractive, but even imperative. Here, we present a survey of techniques for approximate computing (AC). We discuss strategies for finding approximable program portions and monitoring output quality, techniques for using AC in different processing units (e.g., CPU, GPU and FPGA), processor components, memory technologies etc., and programming frameworks for AC. Moreover, we classify these techniques based on several key characteristics to emphasize their similarities and differences. Finally, the aim of this paper is tomore » provide insights to researchers into working of AC techniques and inspire more efforts in this area to make AC the mainstream computing approach in future systems.« less

  7. Drag reducing effects of polymer additives in a plate heat exchanger for the OTEC system

    SciTech Connect (OSTI)

    Kim, N.; Yoon, S.; Kim, C.; Seo, T.

    1999-07-01

    Experiments were undertaken for a 15kW Alfa-Laval plate heat exchanger utilizing polyethylene oxide as a polymer additive. Concentrations of polymer additives were 5, 10, 20, 30, 40, 50, 100, 200 and 400 wppm at 25 C and mass flow rates were 0.6kg/s, 0.7kg/s, 0.8kg/s and 0.9kg/s in normal operating ranges of the plate heat exchanger. The maximum effects of drag reductions were found at 20 wppm polymer concentration and at approximately 0.7kg/s of mass flow rate. The results show that there exist optimum polymer concentration and at approximately 0.7kg/s of mass flow rate. The results show that there exist optimum polymer concentration and mass flow rate for the plate heat exchanger for maximum drag reduction effects. In most cases, drag reduction of approximately 20% has been obtained. It means considerable savings in pumping power for a large size OTEC plant.

  8. An improved proximity force approximation for electrostatics

    SciTech Connect (OSTI)

    Fosco, Cesar D.; Instituto Balseiro, Universidad Nacional de Cuyo, R8402AGP Bariloche ; Lombardo, Fernando C.; IFIBA ; Mazzitelli, Francisco D.

    2012-08-15

    A quite straightforward approximation for the electrostatic interaction between two perfectly conducting surfaces suggests itself when the distance between them is much smaller than the characteristic lengths associated with their shapes. Indeed, in the so called 'proximity force approximation' the electrostatic force is evaluated by first dividing each surface into a set of small flat patches, and then adding up the forces due two opposite pairs, the contributions of which are approximated as due to pairs of parallel planes. This approximation has been widely and successfully applied in different contexts, ranging from nuclear physics to Casimir effect calculations. We present here an improvement on this approximation, based on a derivative expansion for the electrostatic energy contained between the surfaces. The results obtained could be useful for discussing the geometric dependence of the electrostatic force, and also as a convenient benchmark for numerical analyses of the tip-sample electrostatic interaction in atomic force microscopes. - Highlights: Black-Right-Pointing-Pointer The proximity force approximation (PFA) has been widely used in different areas. Black-Right-Pointing-Pointer The PFA can be improved using a derivative expansion in the shape of the surfaces. Black-Right-Pointing-Pointer We use the improved PFA to compute electrostatic forces between conductors. Black-Right-Pointing-Pointer The results can be used as an analytic benchmark for numerical calculations in AFM. Black-Right-Pointing-Pointer Insight is provided for people who use the PFA to compute nuclear and Casimir forces.

  9. Geothermal Heat Pump Manufacturing Activities

    Gasoline and Diesel Fuel Update (EIA)

    ARI-320 ARI-325330 ARI-870 Other Non-ARI Rated 2008 13.1 19.5 17.5 13.5 2009 14.6 20.4 18.2 14.3 ARI-320 Water-Source Heat Pumps. ARI-325 Ground Water-Source Heat Pumps. ...

  10. Geothermal Heat Pump Manufacturing Activities

    Gasoline and Diesel Fuel Update (EIA)

    ARI-320 ARI-325330 ARI-870 Other Non-ARI Rated 2008 4.4 4.0 4.2 3.6 2009 3.9 4.1 4.3 3.8 ARI-320 Water-Source Heat Pumps. ARI-325 Ground Water-Source Heat Pumps. ARI-330 ...

  11. Heat collector

    DOE Patents [OSTI]

    Merrigan, M.A.

    1981-06-29

    A heat collector and method suitable for efficiently and cheaply collecting solar and other thermal energy are provided. The collector employs a heat pipe in a gravity-assist mode and is not evacuated. The collector has many advantages, some of which include ease of assembly, reduced structural stresses on the heat pipe enclosure, and a low total materials cost requirement. Natural convective forces drive the collector, which after startup operates entirely passively due in part to differences in molecular weights of gaseous components within the collector.

  12. Heat collector

    DOE Patents [OSTI]

    Merrigan, Michael A.

    1984-01-01

    A heat collector and method suitable for efficiently and cheaply collecting solar and other thermal energy are provided. The collector employs a heat pipe in a gravity-assist mode and is not evacuated. The collector has many advantages, some of which include ease of assembly, reduced structural stresses on the heat pipe enclosure, and a low total materials cost requirement. Natural convective forces drive the collector, which after startup operates entirely passively due in part to differences in molecular weights of gaseous components within the collector.

  13. Low-order modeling of internal heat transfer in biomass particle pyrolysis

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wiggins, Gavin M.; Daw, C. Stuart; Ciesielski, Peter N.

    2016-05-11

    We present a computationally efficient, one-dimensional simulation methodology for biomass particle heating under conditions typical of fast pyrolysis. Our methodology is based on identifying the rate limiting geometric and structural factors for conductive heat transport in biomass particle models with realistic morphology to develop low-order approximations that behave appropriately. Comparisons of transient temperature trends predicted by our one-dimensional method with three-dimensional simulations of woody biomass particles reveal good agreement, if the appropriate equivalent spherical diameter and bulk thermal properties are used. Here, we conclude that, for particle sizes and heating regimes typical of fast pyrolysis, it is possible to simulatemore » biomass particle heating with reasonable accuracy and minimal computational overhead, even when variable size, aspherical shape, anisotropic conductivity, and complex, species-specific internal pore geometry are incorporated.« less

  14. Approximations of very weak solutions to boundary-value problems.

    SciTech Connect (OSTI)

    Berggren, Martin Olof

    2003-03-01

    Standard weak solutions to the Poisson problem on a bounded domain have square-integrable derivatives, which limits the admissible regularity of inhomogeneous data. The concept of solution may be further weakened in order to define solutions when data is rough, such as for inhomogeneous Dirichlet data that is only square-integrable over the boundary. Such very weak solutions satisfy a nonstandard variational form (u, v) = G(v). A Galerkin approximation combined with an approximation of the right-hand side G defines a finite-element approximation of the very weak solution. Applying conforming linear elements leads to a discrete solution equivalent to the text-book finite-element solution to the Poisson problem in which the boundary data is approximated by L{sub 2}-projections. The L{sub 2} convergence rate of the discrete solution is O(h{sub s}) for some s {element_of} (0,1/2) that depends on the shape of the domain, asserting a polygonal (two-dimensional) or polyhedral (three-dimensional) domain without slits and (only) square-integrable boundary data.

  15. HEAT EXCHANGER

    DOE Patents [OSTI]

    Fox, T.H. III; Richey, T. Jr.; Winders, G.R.

    1962-10-23

    A heat exchanger is designed for use in the transfer of heat between a radioactive fiuid and a non-radioactive fiuid. The exchanger employs a removable section containing the non-hazardous fluid extending into the section designed to contain the radioactive fluid. The removable section is provided with a construction to cancel out thermal stresses. The stationary section is pressurized to prevent leakage of the radioactive fiuid and to maintain a safe, desirable level for this fiuid. (AEC)

  16. Acoustically enhanced heat exchange and drying apparatus

    DOE Patents [OSTI]

    Bramlette, T.T.; Keller, J.O.

    1987-07-10

    A heat transfer drying apparatus includes an acoustically augmented heat transfer chamber for receiving material to be dried. The chamber includes a first heat transfer gas inlet, a second heat transfer gas inlet, a material inlet, and a gas outlet which also serves as a dried material and gas outlet. A non-pulsing first heat transfer gas source provides a first drying gas to the acoustically augmented heat transfer chamber through the first heat transfer gas inlet. A valveless, continuous second heat transfer gas source provides a second drying gas to the acoustically augmented heat transfer chamber through the second heat transfer gas inlet. The second drying gas also generates acoustic waves which bring about acoustical coupling with the gases in the acoustically augmented heat transfer chamber. The second drying gas itself oscillates at an acoustic frequency of approximately 180 Hz due to fluid mechanical motion in the gas. The oscillations of the second heat transfer gas coupled to the first heat transfer gas in the acoustically augmented heat transfer chamber enhance heat and mass transfer by convection within the chamber. 3 figs.

  17. Corrosive resistant heat exchanger

    DOE Patents [OSTI]

    Richlen, Scott L.

    1989-01-01

    A corrosive and errosive resistant heat exchanger which recovers heat from a contaminated heat stream. The heat exchanger utilizes a boundary layer of innocuous gas, which is continuously replenished, to protect the heat exchanger surface from the hot contaminated gas. The innocuous gas is conveyed through ducts or perforations in the heat exchanger wall. Heat from the heat stream is transferred by radiation to the heat exchanger wall. Heat is removed from the outer heat exchanger wall by a heat recovery medium.

  18. Thermal effects and sudden decay approximation in the curvaton scenario

    SciTech Connect (OSTI)

    Kitajima, Naoya; Takesako, Tomohiro; Yokoyama, Shuichiro; Langlois, David; Takahashi, Tomo E-mail: langlois@apc.univ-paris7.fr E-mail: takesako@icrr.u-tokyo.ac.jp

    2014-10-01

    We study the impact of a temperature-dependent curvaton decay rate on the primordial curvature perturbation generated in the curvaton scenario. Using the familiar sudden decay approximation, we obtain an analytical expression for the curvature perturbation after the decay of the curvaton. We then investigate numerically the evolution of the background and of the perturbations during the decay. We first show that the instantaneous transfer coefficient, related to the curvaton energy fraction at the decay, can be extended into a more general parameter, which depends on the net transfer of the curvaton energy into radiation energy or, equivalently, on the total entropy ratio after the complete curvaton decay. We then compute the curvature perturbation and compare this result with the sudden decay approximation prediction.

  19. Cooperative heat transfer and ground coupled storage system

    DOE Patents [OSTI]

    Metz, P.D.

    A cooperative heat transfer and ground coupled storage system wherein collected solar heat energy is ground stored and permitted to radiate into the adjacent ground for storage therein over an extended period of time when such heat energy is seasonally maximally available. Thereafter, when said heat energy is seasonally minimally available and has propagated through the adjacent ground a substantial distance, the stored heat energy may be retrieved by a circumferentially arranged heat transfer means having a high rate of heat transfer.

  20. Cooperative heat transfer and ground coupled storage system

    DOE Patents [OSTI]

    Metz, Philip D.

    1982-01-01

    A cooperative heat transfer and ground coupled storage system wherein collected solar heat energy is ground stored and permitted to radiate into the adjacent ground for storage therein over an extended period of time when such heat energy is seasonally maximally available. Thereafter, when said heat energy is seasonally minimally available and has propagated through the adjacent ground a substantial distance, the stored heat energy may be retrieved by a circumferentially arranged heat transfer means having a high rate of heat transfer.

  1. Total Space Heating Water Heating Cook-

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    Tables Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All Buildings* ... 634 578 46 1 Q 116.4 106.3...

  2. Second derivatives for approximate spin projection methods

    SciTech Connect (OSTI)

    Thompson, Lee M.; Hratchian, Hrant P.

    2015-02-07

    The use of broken-symmetry electronic structure methods is required in order to obtain correct behavior of electronically strained open-shell systems, such as transition states, biradicals, and transition metals. This approach often has issues with spin contamination, which can lead to significant errors in predicted energies, geometries, and properties. Approximate projection schemes are able to correct for spin contamination and can often yield improved results. To fully make use of these methods and to carry out exploration of the potential energy surface, it is desirable to develop an efficient second energy derivative theory. In this paper, we formulate the analytical second derivatives for the Yamaguchi approximate projection scheme, building on recent work that has yielded an efficient implementation of the analytical first derivatives.

  3. Rate Schedules

    Broader source: Energy.gov [DOE]

    One of the major responsibilities of Southeastern is to design, formulate, and justify rate schedules. Repayment studies prepared by the agency determine revenue requirements and appropriate rate...

  4. Heating apparatus

    SciTech Connect (OSTI)

    Page, V. J.

    1981-02-10

    A solar energy heating apparatus is described comprising means for concentrating solar energy incident thereon at an absorption station, an absorber located at the said absorption station for absorbing solar energy concentrated thereat, a first passageway associated with the said energy concentrating means for directing fluid so as to be preheated by the proportion of the incident energy absorbed by the said means, a second passageway associated with the absorber for effecting principal heating of fluid directed therethrough. The second passageway is such that on directing fluid through the first passageway it is initially preheated by the proportion of the incident energy absorbed by the energy concentrating means, the preheated fluid thereafter being directed to the second passageway where the principal heating takes place.

  5. PIA - Northeast Home Heating Oil Reserve System (Heating Oil...

    Energy Savers [EERE]

    Northeast Home Heating Oil Reserve System (Heating Oil) PIA - Northeast Home Heating Oil Reserve System (Heating Oil) PIA - Northeast Home Heating Oil Reserve System (Heating Oil)...

  6. Relativistic Random Phase Approximation At Finite Temperature

    SciTech Connect (OSTI)

    Niu, Y. F.; Paar, N.; Vretenar, D.; Meng, J.

    2009-08-26

    The fully self-consistent finite temperature relativistic random phase approximation (FTRRPA) has been established in the single-nucleon basis of the temperature dependent Dirac-Hartree model (FTDH) based on effective Lagrangian with density dependent meson-nucleon couplings. Illustrative calculations in the FTRRPA framework show the evolution of multipole responses of {sup 132}Sn with temperature. With increased temperature, in both monopole and dipole strength distributions additional transitions appear in the low energy region due to the new opened particle-particle and hole-hole transition channels.

  7. Waste Heat to Power Market Assessment

    SciTech Connect (OSTI)

    Elson, Amelia; Tidball, Rick; Hampson, Anne

    2015-03-01

    Waste heat to power (WHP) is the process of capturing heat discarded by an existing process and using that heat to generate electricity. In the industrial sector, waste heat streams are generated by kilns, furnaces, ovens, turbines, engines, and other equipment. In addition to processes at industrial plants, waste heat streams suitable for WHP are generated at field locations, including landfills, compressor stations, and mining sites. Waste heat streams are also produced in the residential and commercial sectors, but compared to industrial sites these waste heat streams typically have lower temperatures and much lower volumetric flow rates. The economic feasibility for WHP declines as the temperature and flow rate decline, and most WHP technologies are therefore applied in industrial markets where waste heat stream characteristics are more favorable. This report provides an assessment of the potential market for WHP in the industrial sector in the United States.

  8. Bayonet heat exchangers in heat-assisted Stirling heat pump

    SciTech Connect (OSTI)

    Yagyu, S.; Fukuyama, Y.; Morikawa, T.; Isshiki, N.; Satoh, I.; Corey, J.; Fellows, C.

    1998-07-01

    The Multi-Temperature Heat Supply System is a research project creating a city energy system with lower environmental load. This system consists of a gas-fueled internal combustion engine and a heat-assisted Stirling heat pump utilizing shaft power and thermal power in a combination of several cylinders. The heat pump is mainly driven by engine shaft power and is partially assisted by thermal power from engine exhaust heat source. Since this heat pump is operated by proportioning the two energy sources to match the characteristics of the driving engine, the system is expected to produce cooling and heating water at high COP. This paper describes heat exchanger development in the project to develop a heat-assisted Stirling heat pump. The heat pump employs the Bayonet type heat exchangers (BHX Type I) for supplying cold and hot water and (BHX Type II) for absorbing exhaust heat from the driving engine. The heat exchanger design concepts are presented and their heat transfer and flow loss characteristics in oscillating gas flow are investigated. The main concern in the BHX Type I is an improvement of gas side heat transfer and the spirally finned tubes were applied to gas side of the heat exchanger. For the BHX Type II, internal heat transfer characteristics are the main concern. Shell-and-tube type heat exchangers are widely used in Stirling machines. However, since brazing is applied to the many tubes for their manufacturing processes, it is very difficult to change flow passages to optimize heat transfer and loss characteristics once they have been made. The challenge was to enhance heat transfer on the gas side to make a highly efficient heat exchanger with fewer parts. It is shown that the Bayonet type heat exchanger can have good performance comparable to conventional heat exchangers.

  9. Heat exchanger for power generation equipment

    DOE Patents [OSTI]

    Nirmalan, Nirm Velumylm; Bowman, Michael John

    2005-06-14

    A heat exchanger for a turbine is provided wherein the heat exchanger comprises a heat transfer cell comprising a sheet of material having two opposed ends and two opposed sides. In addition, a plurality of concavities are disposed on a surface portion of the sheet of material so as to cause hydrodynamic interactions and affect a heat transfer rate of the turbine between a fluid and the concavities when the fluid is disposed over the concavities.

  10. Rate of reduction of ore-carbon composites: Part II. Modeling of reduction in extended composites

    SciTech Connect (OSTI)

    Fortini, O.M.; Fruehan, R.J.

    2005-12-01

    A new process for ironmaking was proposed using a rotary hearth furnace and an iron bath smelter to produce iron employing wood charcoal as an energy source and reductant. This paper examines reactions in composite pellet samples with sizes close to sizes used in industrial practice (10 to 16 min in diameter). A model was constructed using the combined kinetic mechanism developed in Part I of this series of articles along with equations for the computation of pellet temperature and shrinkage during the reaction. The analysis of reaction rates measured for pellets with wood charcoal showed that heat transfer plays a significant role in their overall rate of reaction at elevated temperatures. The slower rates measured in pellets containing coal char show that the intrinsic kinetics of carbon oxidation is more significant than heat transfer. Model calculations suggest that the rates are highly sensitive to the thermal conductivity of pellets containing wood charcoal and are less sensitive to the external conditions of heat transfer. It was seen that the changes in pellet surface area and diameter due to shrinkage introduce little change on reaction rates. The model developed provides an adequate description of pellets of wood charcoal up to circa 90% of reduction. Experimentally determined rates of reduction of iron oxide by wood charcoal were approximately 5 to 10 times faster than rates measured in pellets with coal char.

  11. Comparison of Methods for Calculating Radiative Heat Transfer

    SciTech Connect (OSTI)

    Schock, Alfred; Abbate, M J

    2012-01-19

    Various approximations for calculating radioactive heat transfer between parallel surfaces are evaluated. This is done by applying the approximations based on total emissivities to a special case of known spectral emissivities, for which exact heat transfer calculations are possible. Comparison of results indicates that the best approximation is obtained by basing the emissivity of the receiving surface primarily on the temperature of the emitter. A specific model is shown to give excellent agreement over a very wide range of values.

  12. Semiclassical approximation to supersymmetric quantum gravity

    SciTech Connect (OSTI)

    Kiefer, Claus; Lueck, Tobias; Moniz, Paulo

    2005-08-15

    We develop a semiclassical approximation scheme for the constraint equations of supersymmetric canonical quantum gravity. This is achieved by a Born-Oppenheimer type of expansion, in analogy to the case of the usual Wheeler-DeWitt equation. The formalism is only consistent if the states at each order depend on the gravitino field. We recover at consecutive orders the Hamilton-Jacobi equation, the functional Schroedinger equation, and quantum gravitational correction terms to this Schroedinger equation. In particular, the following consequences are found: (i) the Hamilton-Jacobi equation and therefore the background spacetime must involve the gravitino, (ii) a (many-fingered) local time parameter has to be present on super Riem {sigma} (the space of all possible tetrad and gravitino fields) (iii) quantum supersymmetric gravitational corrections affect the evolution of the very early Universe. The physical meaning of these equations and results, in particular, the similarities to and differences from the pure bosonic case, are discussed.

  13. Heat exchanger containing a component capable of discontinuous movement

    DOE Patents [OSTI]

    Wilson, David Gordon

    2001-04-17

    Regenerative heat exchangers are described for transferring heat between hot and cold fluids. The heat exchangers have seal-leakage rates significantly less than those of conventional regenerative heat exchangers because the matrix is discontinuously moved and is releasably sealed while in a stationary position. Both rotary and modular heat exchangers are described. Also described are methods for transferring heat between a hot and cold fluid using the discontinuous movement of matrices.

  14. Heat exchanger containing a component capable of discontinuous movement

    DOE Patents [OSTI]

    Wilson, D.G.

    1993-11-09

    Regenerative heat exchangers are described for transferring heat between hot and cold fluids. The heat exchangers have seal-leakage rates significantly less than those of conventional regenerative heat exchangers because the matrix is discontinuously moved and is releasably sealed while in a stationary position. Both rotary and modular heat exchangers are described. Also described are methods for transferring heat between a hot and cold fluid using the discontinuous movement of matrices. 11 figures.

  15. Heat exchanger containing a component capable of discontinuous movement

    DOE Patents [OSTI]

    Wilson, David G.

    1993-01-01

    Regenerative heat exchangers are described for transferring heat between hot and cold fluids. The heat exchangers have seal-leakage rates significantly less than those of conventional regenerative heat exchangers because the matrix is discontinuously moved and is releasably sealed while in a stationary position. Both rotary and modular heat exchangers are described. Also described are methods for transferring heat between a hot and cold fluid using the discontinuous movement of matrices.

  16. Heat exchanger containing a component capable of discontinuous movement

    DOE Patents [OSTI]

    Wilson, David Gordon

    2002-01-01

    Regenerative heat exchangers are described for transferring heat between hot and cold fluids. The heat exchangers have seal-leakage rates significantly less than those of conventional regenerative heat exchangers because the matrix is discontinuously moved and is releasably sealed while in a stationary position. Both rotary and modular heat exchangers are described. Also described are methods for transferring heat between a hot and cold fluid using the discontinuous movement of matrices.

  17. Heat pump system

    DOE Patents [OSTI]

    Swenson, Paul F.; Moore, Paul B.

    1979-01-01

    An air heating and cooling system for a building includes an expansion-type refrigeration circuit and a heat engine. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The heat engine includes a heat rejection circuit having a source of rejected heat and a primary heat exchanger connected to the source of rejected heat. The heat rejection circuit also includes an evaporator in heat exchange relation with the primary heat exchanger, a heat engine indoor heat exchanger, and a heat engine outdoor heat exchanger. The indoor heat exchangers are disposed in series air flow relationship, with the heat engine indoor heat exchanger being disposed downstream from the refrigeration circuit indoor heat exchanger. The outdoor heat exchangers are also disposed in series air flow relationship, with the heat engine outdoor heat exchanger disposed downstream from the refrigeration circuit outdoor heat exchanger. A common fluid is used in both of the indoor heat exchangers and in both of the outdoor heat exchangers. In a first embodiment, the heat engine is a Rankine cycle engine. In a second embodiment, the heat engine is a non-Rankine cycle engine.

  18. Heat pump system

    DOE Patents [OSTI]

    Swenson, Paul F.; Moore, Paul B.

    1982-01-01

    An air heating and cooling system for a building includes an expansion-type refrigeration circuit and a heat engine. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The heat engine includes a heat rejection circuit having a source of rejected heat and a primary heat exchanger connected to the source of rejected heat. The heat rejection circuit also includes an evaporator in heat exchange relation with the primary heat exchanger, a heat engine indoor heat exchanger, and a heat engine outdoor heat exchanger. The indoor heat exchangers are disposed in series air flow relationship, with the heat engine indoor heat exchanger being disposed downstream from the refrigeration circuit indoor heat exchanger. The outdoor heat exchangers are also disposed in series air flow relationship, with the heat engine outdoor heat exchanger disposed downstream from the refrigeration circuit outdoor heat exchanger. A common fluid is used in both of the indoor heat exchanges and in both of the outdoor heat exchangers. In a first embodiment, the heat engine is a Rankine cycle engine. In a second embodiment, the heat engine is a non-Rankine cycle engine.

  19. Heat transfer and heat exchangers reference handbook

    SciTech Connect (OSTI)

    Not Available

    1991-01-15

    The purpose of this handbook is to provide Rocky Flats personnel with an understanding of the basic concepts of heat transfer and the operation of heat exchangers.

  20. Heating systems for heating subsurface formations

    DOE Patents [OSTI]

    Nguyen, Scott Vinh; Vinegar, Harold J.

    2011-04-26

    Methods and systems for heating a subsurface formation are described herein. A heating system for a subsurface formation includes a sealed conduit positioned in an opening in the formation and a heat source. The sealed conduit includes a heat transfer fluid. The heat source provides heat to a portion of the sealed conduit to change phase of the heat transfer fluid from a liquid to a vapor. The vapor in the sealed conduit rises in the sealed conduit, condenses to transfer heat to the formation and returns to the conduit portion as a liquid.

  1. Heat exchanger

    DOE Patents [OSTI]

    Brackenbury, P.J.

    1983-12-08

    A heat exchanger comparising a shell attached at its open end to one side of a tube sheet and a detachable head connected to the other side of said tube sheet. The head is divided into a first and second chamber in fluid communication with a nozzle inlet and nozzle outlet, respectively, formed in said tube sheet. A tube bundle is mounted within said shell and is provided with inlets and outlets formed in said tube sheet in communication with said first and second chambers, respectively.

  2. Heat exchanger

    DOE Patents [OSTI]

    Brackenbury, Phillip J.

    1986-01-01

    A heat exchanger comparising a shell attached at its open end to one side of a tube sheet and a detachable head connected to the other side of said tube sheet. The head is divided into a first and second chamber in fluid communication with a nozzle inlet and nozzle outlet, respectively, formed in said tube sheet. A tube bundle is mounted within said shell and is provided with inlets and outlets formed in said tube sheet in communication with said first and second chambers, respectively.

  3. Heat exchanger

    DOE Patents [OSTI]

    Brackenbury, Phillip J.

    1986-04-01

    A heat exchanger comparising a shell attached at its open end to one side of a tube sheet and a detachable head connected to the other side of said tube sheet. The head is divided into a first and second chamber in fluid communication with a nozzle inlet and nozzle outlet, respectively, formed in said tube sheet. A tube bundle is mounted within said shell and is provided with inlets and outlets formed in said tube sheet in communication with said first and second chambers, respectively.

  4. Examination of frit vent from Sixty-Watt Heat Source simulant fueled clad vent set

    SciTech Connect (OSTI)

    Ulrich, G.B.

    1995-11-01

    The flow rate and the metallurgical condition of a frit vent from a simulant-fueled clad vent set (CVS) that had been hot isostatically pressed (HIP) for the Sixty-Watt Heat Source program were evaluated. The flow rate form the defueled vent cup subassembly was reduced approximately 25% from the original flow rate. No obstructions were found to account for the reduced flow rate. Measurements indicate that the frit vent powder thickness was reduced about 30%. Most likely, the powder was compressed during the HIP operation, which increased the density of the powder layer and thus reduced the flow rate of the assembly. All other observed manufacturing attributes appeared to be normal, but the vent hole activation technique needs further refinement before it is used in applications requiring maximum CVS integrity.

  5. Finance & Rates

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    all of its costs in the rates it charges customers for wholesale electricity and transmission services. The agency is committed to careful cost management consistent with its...

  6. Molecular Solid EOS based on Quasi-Harmonic Oscillator approximation for phonons

    SciTech Connect (OSTI)

    Menikoff, Ralph

    2014-09-02

    A complete equation of state (EOS) for a molecular solid is derived utilizing a Helmholtz free energy. Assuming that the solid is nonconducting, phonon excitations dominate the specific heat. Phonons are approximated as independent quasi-harmonic oscillators with vibrational frequencies depending on the specific volume. The model is suitable for calibrating an EOS based on isothermal compression data and infrared/Raman spectroscopy data from high pressure measurements utilizing a diamond anvil cell. In contrast to a Mie-Gr ̈uneisen EOS developed for an atomic solid, the specific heat and Gr ̈uneisen coefficient depend on both density and temperature.

  7. Bond selective chemistry beyond the adiabatic approximation

    SciTech Connect (OSTI)

    Butler, L.J.

    1993-12-01

    One of the most important challenges in chemistry is to develop predictive ability for the branching between energetically allowed chemical reaction pathways. Such predictive capability, coupled with a fundamental understanding of the important molecular interactions, is essential to the development and utilization of new fuels and the design of efficient combustion processes. Existing transition state and exact quantum theories successfully predict the branching between available product channels for systems in which each reaction coordinate can be adequately described by different paths along a single adiabatic potential energy surface. In particular, unimolecular dissociation following thermal, infrared multiphoton, or overtone excitation in the ground state yields a branching between energetically allowed product channels which can be successfully predicted by the application of statistical theories, i.e. the weakest bond breaks. (The predictions are particularly good for competing reactions in which when there is no saddle point along the reaction coordinates, as in simple bond fission reactions.) The predicted lack of bond selectivity results from the assumption of rapid internal vibrational energy redistribution and the implicit use of a single adiabatic Born-Oppenheimer potential energy surface for the reaction. However, the adiabatic approximation is not valid for the reaction of a wide variety of energetic materials and organic fuels; coupling between the electronic states of the reacting species play a a key role in determining the selectivity of the chemical reactions induced. The work described below investigated the central role played by coupling between electronic states in polyatomic molecules in determining the selective branching between energetically allowed fragmentation pathways in two key systems.

  8. OBSERVATIONAL TEST OF STOCHASTIC HEATING IN LOW-{beta} FAST-SOLAR-WIND STREAMS

    SciTech Connect (OSTI)

    Bourouaine, Sofiane; Chandran, Benjamin D. G.

    2013-09-10

    Spacecraft measurements show that protons undergo substantial perpendicular heating during their transit from the Sun to the outer heliosphere. In this paper, we use Helios 2 measurements to investigate whether stochastic heating by low-frequency turbulence is capable of explaining this perpendicular heating. We analyze Helios 2 magnetic field measurements in low-{beta} fast-solar-wind streams between heliocentric distances r = 0.29 AU and r = 0.64 AU to determine the rms amplitude of the fluctuating magnetic field, {delta}B{sub p}, near the proton gyroradius scale {rho}{sub p}. We then evaluate the stochastic heating rate Q{sub stoch} using the measured value of {delta}B{sub p} and a previously published analytical formula for Q{sub stoch}. Using Helios measurements we estimate the ''empirical'' perpendicular heating rate Q{sub Up-Tack emp} = (k{sub B}/m{sub p}) BV (d/dr) (T{sub Up-Tack p}/B) that is needed to explain the T{sub p} profile. We find that Q{sub stoch} {approx} Q{sub emp}, but only if a key dimensionless constant appearing in the formula for Q{sub stoch} lies within a certain range of values. This range is approximately the same throughout the radial interval that we analyze and is consistent with the results of numerical simulations of the stochastic heating of test particles in reduced magnetohydrodynamic turbulence. These results support the hypothesis that stochastic heating accounts for much of the perpendicular proton heating occurring in low-{beta} fast-wind streams.

  9. Heat pipe methanator

    DOE Patents [OSTI]

    Ranken, William A.; Kemme, Joseph E.

    1976-07-27

    A heat pipe methanator for converting coal gas to methane. Gravity return heat pipes are employed to remove the heat of reaction from the methanation promoting catalyst, transmitting a portion of this heat to an incoming gas pre-heat section and delivering the remainder to a steam generating heat exchanger.

  10. Dual source heat pump

    DOE Patents [OSTI]

    Ecker, Amir L.; Pietsch, Joseph A.

    1982-01-01

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

  11. Segmented heat exchanger

    DOE Patents [OSTI]

    Baldwin, Darryl Dean; Willi, Martin Leo; Fiveland, Scott Byron; Timmons, Kristine Ann

    2010-12-14

    A segmented heat exchanger system for transferring heat energy from an exhaust fluid to a working fluid. The heat exchanger system may include a first heat exchanger for receiving incoming working fluid and the exhaust fluid. The working fluid and exhaust fluid may travel through at least a portion of the first heat exchanger in a parallel flow configuration. In addition, the heat exchanger system may include a second heat exchanger for receiving working fluid from the first heat exchanger and exhaust fluid from a third heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the second heat exchanger in a counter flow configuration. Furthermore, the heat exchanger system may include a third heat exchanger for receiving working fluid from the second heat exchanger and exhaust fluid from the first heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the third heat exchanger in a parallel flow configuration.

  12. Climate, extreme heat, and electricity demand in California

    SciTech Connect (OSTI)

    Miller, N.L.; Hayhoe, K.; Jin, J.; Auffhammer, M.

    2008-04-01

    Climate projections from three atmosphere-ocean climate models with a range of low to mid-high temperature sensitivity forced by the Intergovernmental Panel for Climate Change SRES higher, middle, and lower emission scenarios indicate that, over the 21st century, extreme heat events for major cities in heavily air-conditioned California will increase rapidly. These increases in temperature extremes are projected to exceed the rate of increase in mean temperature, along with increased variance. Extreme heat is defined here as the 90 percent exceedance probability (T90) of the local warmest summer days under the current climate. The number of extreme heat days in Los Angeles, where T90 is currently 95 F (32 C), may increase from 12 days to as many as 96 days per year by 2100, implying current-day heat wave conditions may last for the entire summer, with earlier onset. Overall, projected increases in extreme heat under the higher A1fi emission scenario by 2070-2099 tend to be 20-30 percent higher than those projected under the lower B1 emission scenario, ranging from approximately double the historical number of days for inland California cities (e.g. Sacramento and Fresno), up to four times for previously temperate coastal cities (e.g. Los Angeles, San Diego). These findings, combined with observed relationships between high temperature and electricity demand for air-conditioned regions, suggest potential shortfalls in transmission and supply during T90 peak electricity demand periods. When the projected extreme heat and peak demand for electricity are mapped onto current availability, maintaining technology and population constant only for demand side calculations, we find the potential for electricity deficits as high as 17 percent. Similar increases in extreme heat days are suggested for other locations across the U.S. southwest, as well as for developing nations with rapidly increasing electricity demands. Electricity response to recent extreme heat events, such

  13. Particle-number conservation in static-path approximation for thermal superfluid systems

    SciTech Connect (OSTI)

    Kaneko, K.; Schiller, A.

    2007-12-15

    By applying particle-number projection to the static-path approximation (SPA), the heat capacity and the breakdown of pairing correlations are investigated in the thermally excited, superfluid systems {sup 172}Yb, {sup 94}Mo, and {sup 56}Fe. For the heavy nucleus {sup 172}Yb, the heat capacities in both the SPA and the number-projected SPA (NPSPA) exhibit an S shape; the difference between the SPA and NPSPA heat-capacity curves is not very large and the particle-number projection thereby enhances the S shape already seen in the SPA. The temperature at which the S-shape of heat capacity curve occurs parallels the temperature of the breakdown of pairing correlations as indicated by the effective pairing gap. However, for the comparatively lighter nuclei {sup 94}Mo and {sup 56}Fe, the SPA does not produce an S-shaped heat capacity on its own; only after particle-number projection the S shape appears in the heat-capacity curve. For {sup 94}Mo, we compare the NPSPA result with thermal odd-even mass differences, which are regarded as a direct measure of the pairing gap.

  14. Radiative Heating in Underexplored Bands Campaign (RHUBC)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Bands Campaign (RHUBC) D. Turner and E. Mlawer RHUBC Breakout Session 2008 ARM Science Team Meeting 13 March, 2008 Norfolk, Virginia Motivation * Radiative heating/cooling in the mid-troposphere modulate the vertical motions of the atmosphere - This heating/cooling occurs primarily in water vapor absorption bands that are opaque at the surface * Approximately 40% of the OLR comes from the far-IR * Until recently, the observational tools were not available to evaluate the accuracy of the far-IR

  15. Approximate simulation of CO[sub 2] and H[sub 2]S absorption into aqueous alkanolamines

    SciTech Connect (OSTI)

    Glasscock, D.A.; Rochelle, G.T. . Dept. of Chemical Engineering)

    1993-08-01

    Rigorous and approximate methods are compared for the simulation of CO[sub 2] absorption into aqueous alkanolamine mixtures of methyldiethanolamine and diethanolamine. In addition, data for the mixtures containing monoethanolamine and the simultaneous absorption of CO[sub 2] and H[sub 2]S are presented. For the rigorous approach, the simplified eddy diffusivity theory is used to simulate the liquid-phase hydrodynamic characteristics. The approximation methods examined are the pseudo-first-order approximation, the interpolation approximation of Wellek et al. (1978), the algebraic combined flux (ACFLUX) approximation and the modified combined flux (MCFLUX) approximation. The latter approximation utilizes the reaction zone concept to determine the kinetic preference of the absorbing gas at the gas-liquid interface. Under the range of conditions studied, the MCFLUX approximation predicts very accurately the CO[sub 2] and H[sub 2]S flux rates in mixed amine systems, as compared with the rigorous solution of the differential equations.

  16. DOE to Sell 35,000 Barrels of Oil from the Northeast Home Heating Oil Reserve

    Broader source: Energy.gov [DOE]

    WASHINGTON, DC - The U.S. Department of Energy announced today that it will sell approximately 35,000 barrels of home heating oil from the Northeast Home Heating Oil Reserve (NEHHOR).  The Reserve...

  17. Comparison of Alternatives to the 2004 Vacuum Vessel Heat Transfer...

    Office of Scientific and Technical Information (OSTI)

    as well as including a small safety-rated pump and HX in parallel to the main circulation pump and HX. The Vacuum Vessel (VV) Primary Heat Transfer System (PHTS) removes heat...

  18. Multiple source heat pump

    DOE Patents [OSTI]

    Ecker, Amir L.

    1983-01-01

    A heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating a fluid in heat exchange relationship with a refrigerant fluid, at least three refrigerant heat exchangers, one for effecting heat exchange with the fluid, a second for effecting heat exchange with a heat exchange fluid, and a third for effecting heat exchange with ambient air; a compressor for compressing the refrigerant; at least one throttling valve connected at the inlet side of a heat exchanger in which liquid refrigerant is vaporized; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circuit and pump for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and directional flow of refrigerant therethrough for selecting a particular mode of operation. Also disclosed are a variety of embodiments, modes of operation, and schematics therefor.

  19. Heat release analysis of engine pressure data

    SciTech Connect (OSTI)

    Gatowski, J.A.; Balles, E.N.; Chun, K.M.; Nelson, F.E.; Ekchian, J.A.; Heywood, J.B.

    1984-01-01

    In analyzing the processes inside the cylinder of an internal combustion engine, the principal diagnostic at the experimenter's disposal is a measured time history of the cylinder pressure. This paper develops, tests, and applies a heat release analysis procedure that maintains simplicity while including the effects of heat transfer, crevice flows and fuel injection. The heat release model uses a one zone description of the cylinder contents with thermodynamic properties represented by a linear approximation. Applications of the analysis to a single-cylinder spark-ignition engine, a special square cross-section visualization spark-ignition engine, and a direct-injection stratified charge engine are presented.

  20. Heating 7. 2 user's manual

    SciTech Connect (OSTI)

    Childs, K.W.

    1993-02-01

    HEATING is a general-purpose conduction heat transfer program written in Fortran 77. HEATING can solve steady-state and/or transient heat conduction problems in one-, two-, or three-dimensional Cartesian, cylindrical, or spherical coordinates. A model may include multiple materials, and the thermal conductivity, density, and specific heat of each material may be both time- and temperature-dependent. The thermal conductivity may also be anisotropic. Materials may undergo change of phase. Thermal properties of materials may be input or may be extracted from a material properties library. Heat-generation rates may be dependent on time, temperature, and position, and boundary temperatures may be time- and position-dependent. The boundary conditions, which may be surface-to-environment or surface-to-surface, may be specified temperatures or any combination of prescribed heat flux, forced convection, natural convection, and radiation. The boundary condition parameters may be time- and/or temperature-dependent. General gray-body radiation problems may be modeled with user-defined factors for radiant exchange. The mesh spacing may be variable along each axis. HEATING uses a runtime memory allocation scheme to avoid having to recompile to match memory requirements for each specific problem. HEATING utilizes free-form input. Three steady-state solution techniques are available: point-successive-overrelaxation iterative method with extrapolation, direct-solution, and conjugate gradient. Transient problems may be solved using any one of several finite-difference schemes: Crank-Nicolson implicit, Classical Implicit Procedure (CIP), Classical Explicit Procedure (CEP), or Levy explicit method. The solution of the system of equations arising from the implicit techniques is accomplished by point-successive-overrelaxation iteration and includes procedures to estimate the optimum acceleration parameter.

  1. Solar heating panel

    SciTech Connect (OSTI)

    Ellsworth, R.L.

    1983-01-18

    A solar heating panel for collecting solar heat energy and method for making same having a heat insulative substrate with a multiplicity of grooves and structural supporting ribs formed therein covered by a thin, flexible heat conductive film to form fluid conducting channels which in turn are connected to manifolds from which fluid is directed into the channels and heated fluid is removed therefrom.

  2. Heat Exchangers for Solar Water Heating Systems | Department...

    Energy Savers [EERE]

    Heat Exchangers for Solar Water Heating Systems Heat Exchangers for Solar Water Heating Systems Image of a heat exchanger. | Photo from iStockphoto.com Image of a heat exchanger. |...

  3. Multifamily Individual Heating and Ventilation Systems, Lawrence...

    Energy Savers [EERE]

    than the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) 62.2 rate; an extensive system of ductwork, smoke and fre dampers, and duct chases ...

  4. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, G.

    1982-06-16

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  5. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, Gershon

    1984-01-01

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  6. Concentrating solar heat collector

    SciTech Connect (OSTI)

    Fattor, A.P.

    1980-09-23

    A heat storage unit is integrated with a collection unit providing a heat supply in off-sun times, and includes movable insulation means arranged to provide insulation during off-sun times for the heat storage unit.

  7. Kethcum District Heating District Heating Low Temperature Geothermal...

    Open Energy Info (EERE)

    Kethcum District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Kethcum District Heating District Heating Low Temperature Geothermal...

  8. Midland District Heating District Heating Low Temperature Geothermal...

    Open Energy Info (EERE)

    Midland District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Midland District Heating District Heating Low Temperature Geothermal...

  9. PIA - Northeast Home Heating Oil Reserve System (Heating Oil...

    Broader source: Energy.gov (indexed) [DOE]

    Northeast Home Heating Oil Reserve System (Heating Oil) PIA - Northeast Home Heating Oil Reserve System (Heating Oil) (3.31 MB) More Documents & Publications PIA - WEB Physical ...

  10. Pagosa Springs District Heating District Heating Low Temperature...

    Open Energy Info (EERE)

    Pagosa Springs District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Pagosa Springs District Heating District Heating Low...

  11. Philip District Heating District Heating Low Temperature Geothermal...

    Open Energy Info (EERE)

    Philip District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Philip District Heating District Heating Low Temperature Geothermal...

  12. Woven heat exchanger

    DOE Patents [OSTI]

    Piscitella, R.R.

    1984-07-16

    This invention relates to a heat exchanger for waste heat recovery from high temperature industrial exhaust streams. In a woven ceramic heat exchanger using the basic tube-in-shell design, each heat exchanger consisting of tube sheets and tube, is woven separately. Individual heat exchangers are assembled in cross-flow configuration. Each heat exchanger is woven from high temperature ceramic fiber, the warp is continuous from tube to tube sheet providing a smooth transition and unitized construction.

  13. Convergence properties of polynomial chaos approximations for L2 random variables.

    SciTech Connect (OSTI)

    Field, Richard V., Jr. (.,; .); Grigoriu, Mircea (Cornell University, Ithaca, NY)

    2007-03-01

    Polynomial chaos (PC) representations for non-Gaussian random variables are infinite series of Hermite polynomials of standard Gaussian random variables with deterministic coefficients. For calculations, the PC representations are truncated, creating what are herein referred to as PC approximations. We study some convergence properties of PC approximations for L{sub 2} random variables. The well-known property of mean-square convergence is reviewed. Mathematical proof is then provided to show that higher-order moments (i.e., greater than two) of PC approximations may or may not converge as the number of terms retained in the series, denoted by n, grows large. In particular, it is shown that the third absolute moment of the PC approximation for a lognormal random variable does converge, while moments of order four and higher of PC approximations for uniform random variables do not converge. It has been previously demonstrated through numerical study that this lack of convergence in the higher-order moments can have a profound effect on the rate of convergence of the tails of the distribution of the PC approximation. As a result, reliability estimates based on PC approximations can exhibit large errors, even when n is large. The purpose of this report is not to criticize the use of polynomial chaos for probabilistic analysis but, rather, to motivate the need for further study of the efficacy of the method.

  14. Total Space Heat-

    Gasoline and Diesel Fuel Update (EIA)

    Commercial Buildings Energy Consumption Survey: Energy End-Use Consumption Tables Total Space Heat- ing Cool- ing Venti- lation Water Heat- ing Light- ing Cook- ing Refrig- eration...

  15. Total Space Heat-

    Gasoline and Diesel Fuel Update (EIA)

    Revised: December, 2008 Total Space Heat- ing Cool- ing Venti- lation Water Heat- ing Light- ing Cook- ing Refrig- eration Office Equip- ment Com- puters Other All Buildings...

  16. Total Space Heat-

    Gasoline and Diesel Fuel Update (EIA)

    Released: September, 2008 Total Space Heat- ing Cool- ing Venti- lation Water Heat- ing Light- ing Cook- ing Refrig- eration Office Equip- ment Com- puters Other All Buildings*...

  17. Waste Heat Recovery

    Office of Environmental Management (EM)

    - PRE-DECISIONAL - DRAFT 1 Waste Heat Recovery 1 Technology Assessment 2 Contents 3 1. ... 2 4 1.1. Introduction to Waste Heat Recovery ......

  18. DOE Announces Award of a Contract to Repurchase Heating Oil for the

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Northeast Home Heating Oil Reserve | Department of Energy Award of a Contract to Repurchase Heating Oil for the Northeast Home Heating Oil Reserve DOE Announces Award of a Contract to Repurchase Heating Oil for the Northeast Home Heating Oil Reserve July 23, 2008 - 2:15pm Addthis WASHINGTON, DC - The U.S. Department of Energy today announced the award of a contract to Hess Corporation for the delivery of approximately 808,625 gallons (approximately 19,250 barrels) of home heating oil for the

  19. Guide to Geothermal Heat Pumps

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    among the most effcient and comfortable heating and cooling technologies available because they use the earth's natural heat to provide heating, cooling, and often, water heating. ...

  20. Rates Meetings and Workshops (pbl/rates)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Rate Case Workshops Other Power Rates-Related Workshops July 1, 2004 - Rates and Finances Workshop (updated June 25, 2004) (financial and rate forecasts and scenarios for FY...

  1. Helically coiled tube heat exchanger

    SciTech Connect (OSTI)

    Harris, A.M.

    1981-08-18

    In a heat exchanger such as a steam generator for a nuclear reactor, two or more bundles of helically coiled tubes are arranged in series with the tubes in each bundle integrally continuing through the tube bundles arranged in series therewith. Pitch values for the tubing in any pair of tube bundles, taken transverse to the path of the reactor coolant flow about the tubes, are selected as a ratio of two unequal integers to permit efficient operation of each tube bundle while maintaining the various tube bundles of the heat exchanger within a compact envelope. Preferably, the helix angle and tube pitch parallel to the path of coolant flow are constant for all tubes in a single bundle so that the tubes are of approximately the same length within each bundle.

  2. Grid-Interactive Renewable Water Heating Economic and Environmental...

    Broader source: Energy.gov (indexed) [DOE]

    1 Grid-Interactive Renewable Water Heating Economic and Environmental Value Grid-interactive renewable water heaters have smart controls that quickly change their charge rate and ...

  3. Increasing Confidence In Geothermal Heat Pump Design Methods...

    Office of Scientific and Technical Information (OSTI)

    ... rate in the ground heat exchangers, allowed us to determine the thermal properties of the soil formation being experienced by the operating GHP system. Outputs from the models ...

  4. Energy and IAQ Implications of Alternative Minimum Ventilation Rates in California Retail and School Buildings

    SciTech Connect (OSTI)

    Dutton, Spencer M.; Fisk, William J.

    2015-01-01

    For a stand-alone retail building, a primary school, and a secondary school in each of the 16 California climate zones, the EnergyPlus building energy simulation model was used to estimate how minimum mechanical ventilation rates (VRs) affect energy use and indoor air concentrations of an indoor-generated contaminant. The modeling indicates large changes in heating energy use, but only moderate changes in total building energy use, as minimum VRs in the retail building are changed. For example, predicted state-wide heating energy consumption in the retail building decreases by more than 50% and total building energy consumption decreases by approximately 10% as the minimum VR decreases from the Title 24 requirement to no mechanical ventilation. The primary and secondary schools have notably higher internal heat gains than in the retail building models, resulting in significantly reduced demand for heating. The school heating energy use was correspondingly less sensitive to changes in the minimum VR. The modeling indicates that minimum VRs influence HVAC energy and total energy use in schools by only a few percent. For both the retail building and the school buildings, minimum VRs substantially affected the predicted annual-average indoor concentrations of an indoor generated contaminant, with larger effects in schools. The shape of the curves relating contaminant concentrations with VRs illustrate the importance of avoiding particularly low VRs.

  5. Cab Heating and Cooling

    SciTech Connect (OSTI)

    Damman, Dennis

    2005-10-31

    Schneider National, Inc., SNI, has concluded the Cab Heating and Cooling evaluation of onboard, engine off idling solutions. During the evaluation period three technologies were tested, a Webasto Airtronic diesel fired heater for cold weather operation, and two different approaches to cab cooling in warm weather, a Webasto Parking Cooler, phase change storage system and a Bergstrom Nite System, a 12 volt electrical air conditioning approach to cooling. Diesel fired cab heaters were concluded to provide adequate heat in winter environments down to 10 F. With a targeted idle reduction of 17%, the payback period is under 2 years. The Webasto Parking Cooler demonstrated the viability of this type of technology, but required significant driver involvement to achieve maximum performance. Drivers rated the technology as ''acceptable'', however, in individual discussions it became apparent they were not satisfied with the system limitations in hot weather, (over 85 F). The Bergstrom Nite system was recognized as an improvement by drivers and required less direct driver input to operate. While slightly improved over the Parking Cooler, the hot temperature limitations were only slightly better. Neither the Parking Cooler or the Nite System showed any payback potential at the targeted 17% idle reduction. Fleets who are starting at a higher idle baseline may have a more favorable payback.

  6. Direct fired heat exchanger

    DOE Patents [OSTI]

    Reimann, Robert C. (Lafayette, NY); Root, Richard A. (Spokane, WA)

    1986-01-01

    A gas-to-liquid heat exchanger system which transfers heat from a gas, generally the combustion gas of a direct-fired generator of an absorption machine, to a liquid, generally an absorbent solution. The heat exchanger system is in a counterflow fluid arrangement which creates a more efficient heat transfer.

  7. Rotary magnetic heat pump

    DOE Patents [OSTI]

    Kirol, Lance D.

    1988-01-01

    A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation.

  8. Woven heat exchanger

    DOE Patents [OSTI]

    Piscitella, Roger R.

    1987-05-05

    In a woven ceramic heat exchanger using the basic tube-in-shell design, each heat exchanger consisting of tube sheets and tube, is woven separately. Individual heat exchangers are assembled in cross-flow configuration. Each heat exchanger is woven from high temperature ceramic fiber, the warp is continuous from tube to tube sheet providing a smooth transition and unitized construction.

  9. Woven heat exchanger

    DOE Patents [OSTI]

    Piscitella, Roger R.

    1987-01-01

    In a woven ceramic heat exchanger using the basic tube-in-shell design, each heat exchanger consisting of tube sheets and tube, is woven separately. Individual heat exchangers are assembled in cross-flow configuration. Each heat exchanger is woven from high temperature ceramic fiber, the warp is continuous from tube to tube sheet providing a smooth transition and unitized construction.

  10. Rotary magnetic heat pump

    DOE Patents [OSTI]

    Kirol, L.D.

    1987-02-11

    A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation. 5 figs.

  11. Evaporative heat transfer in beds of sensible heat pellets

    SciTech Connect (OSTI)

    Arimilli, R.V.; Moy, C.A.

    1989-03-01

    An experimental study of boiling/evaporative heat transfer from heated spheres in vertical packed beds with downward liquid-vapor flow of Refrigerant-113 was conducted. Surface superheats of 1 to 50{degrees}C, mass flow rates of 1.7 to 5.6 Kg/min, sphere diameters of 1.59 and 2.54 cm, quality (i.e., mass fraction of vapor) of the inlet flow of 0.02 to 1.0, and two surface conditions were considered. Instrumented smooth and rough aluminum spheres were used to measure the heat transfer coefficients under steady state conditions. Heat transfer coefficients were independently determined for each sphere at three values three values of surface superheat. The quantitative results of this extensive experimental study are successfully correlated. The correlation equation for the boiling heat transfer coefficients is presented in terms of a homogeneous model. The correlation may be used in the development of numerical models to simulate the transient thermal performance of packed bed thermal energy storage unit while operating as an evaporator. The boiling of the liquid-vapor flow around the spheres in the packed bed was visually observed with a fiber-optic baroscope and recorded on a videotape. The visualization results showed qualitatively the presence of four distinct flow regimes. One of these occurs under saturated inlet conditions and are referred to as the Low-quality, Medium-quality, and High-quality Regimes. The regimes are discussed in detail in this paper.

  12. Charge-conjugation symmetric complete impulse approximation for...

    Office of Scientific and Technical Information (OSTI)

    from the spectator quark (referred to as the relativistic impulse approximation). In this study we also include the contributions from the poles of the quark which interacts with ...

  13. How to Solve Schroedinger Problems by Approximating the Potential Function

    SciTech Connect (OSTI)

    Ledoux, Veerle; Van Daele, Marnix

    2010-09-30

    We give a survey over the efforts in the direction of solving the Schroedinger equation by using piecewise approximations of the potential function. Two types of approximating potentials have been considered in the literature, that is piecewise constant and piecewise linear functions. For polynomials of higher degree the approximating problem is not so easy to integrate analytically. This obstacle can be circumvented by using a perturbative approach to construct the solution of the approximating problem, leading to the so-called piecewise perturbation methods (PPM). We discuss the construction of a PPM in its most convenient form for applications and show that different PPM versions (CPM,LPM) are in fact equivalent.

  14. Quasiparticle random-phase approximation with interactions from...

    Office of Scientific and Technical Information (OSTI)

    Quasiparticle random-phase approximation with interactions from the Similarity Renormalization Group Citation Details In-Document Search Title: Quasiparticle random-phase ...

  15. A Multithreaded Algorithm for Network Alignment Via Approximate...

    Office of Scientific and Technical Information (OSTI)

    The best current approaches are entirely heuristic, and are iterative in nature. They generate real-valued heuristic approximations that must be rounded to find integer solutions. ...

  16. ANALOG QUANTUM NEURON FOR FUNCTIONS APPROXIMATION A. EZHOV; A...

    Office of Scientific and Technical Information (OSTI)

    FOR FUNCTIONS APPROXIMATION A. EZHOV; A. KHROMOV; G. BERMAN 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; IMPLEMENTATION; NERVE CELLS; WAVEGUIDES We describe a system able...

  17. Thulium-170 heat source

    DOE Patents [OSTI]

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

    1992-01-01

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

  18. Heat Treating Apparatus

    DOE Patents [OSTI]

    De Saro, Robert; Bateman, Willis

    2002-09-10

    Apparatus for heat treating a heat treatable material including a housing having an upper opening for receiving a heat treatable material at a first temperature, a lower opening, and a chamber therebetween for heating the heat treatable material to a second temperature higher than the first temperature as the heat treatable material moves through the chamber from the upper to the lower opening. A gas supply assembly is operatively engaged to the housing at the lower opening, and includes a source of gas, a gas delivery assembly for delivering the gas through a plurality of pathways into the housing in countercurrent flow to movement of the heat treatable material, whereby the heat treatable material passes through the lower opening at the second temperature, and a control assembly for controlling conditions within the chamber to enable the heat treatable material to reach the second temperature and pass through the lower opening at the second temperature as a heated material.

  19. Thermoelectric heat exchange element

    DOE Patents [OSTI]

    Callas, James J.; Taher, Mahmoud A.

    2007-08-14

    A thermoelectric heat exchange module includes a first substrate including a heat receptive side and a heat donative side and a series of undulatory pleats. The module may also include a thermoelectric material layer having a ZT value of 1.0 or more disposed on at least one of the heat receptive side and the heat donative side, and an electrical contact may be in electrical communication with the thermoelectric material layer.

  20. Waste Heat Management Options for Improving Industrial Process Heating

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Systems | Department of Energy Waste Heat Management Options for Improving Industrial Process Heating Systems Waste Heat Management Options for Improving Industrial Process Heating Systems This presentation covers typical sources of waste heat from process heating equipment, characteristics of waste heat streams, and options for recovery including Combined Heat and Power. Waste Heat Management Options for Improving Industrial Process Heating Systems (August 20, 2009) (494.7 KB) More

  1. Heat Exchangers for Solar Water Heating Systems | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Exchangers for Solar Water Heating Systems Heat Exchangers for Solar Water Heating Systems Image of a heat exchanger. | Photo from iStockphoto.com Image of a heat exchanger. | Photo from iStockphoto.com Solar water heating systems use heat exchangers to transfer solar energy absorbed in solar collectors to the liquid or air used to heat water or a space. Heat exchangers can be made of steel, copper, bronze, stainless steel, aluminum, or cast iron. Solar heating systems usually use copper,

  2. Comparison of natural convection heat exchangers for solar water heating systems

    SciTech Connect (OSTI)

    Davidson, J.; Liu, W.

    1998-09-15

    Thermosyphon heat exchangers are used in indirect solar water heating systems to avoid using a pump to circulate water from the storage tank to the heat exchanger. In this study, the authors consider the effect of heat exchanger design on system performance. They also compare performance of a system with thermosyphon flow to the same system with a 40W pump in the water loop. In the first part of the study, the authors consider the impact of heat exchanger design on the thermal performance of both one- and two-collector solar water heaters. The comparison is based on Solar Rating and Certification Corporation (SRCC) OG300 simulations. The thermosyphon heat exchangers considered are (1) a one-pass, double wall, 0.22 m{sup 2}, four tube-in-shell heat exchanger manufactured by AAA Service and Supply, Inc., (the Quad-Rod); (2) a two-pass, double wall, 0.2 m{sup 2}, tube-in-shell made by Heliodyne, Inc., but not intended for commercial development; (3) a one-pass, single wall, 0.28 m{sup 2}, 31 tube-in-shell heat exchanger from Young Radiator Company, and (4) a one-pass single-wall, 0.61 m{sup 2}, four coil-in-shell heat exchanger made by ThermoDynamics Ltd. The authors compare performance of the systems with thermosyphon heat exchangers to a system with a 40 W pump used with the Quad-Rod heat exchanger. In the second part of the study, the effects of reducing frictional losses through the heat exchanger and/or the pipes connecting the heat exchanger to the storage tank, and increasing heat transfer area are evaluated in terms of OG300 ratings.

  3. Properties of the Boltzmann equation in the classical approximation

    SciTech Connect (OSTI)

    Tanji, Naoto; Epelbaum, Thomas; Gelis, Francois; Wu, Bin

    2014-12-30

    We study the Boltzmann equation with elastic point-like scalar interactions in two different versions of the the classical approximation. Although solving numerically the Boltzmann equation with the unapproximated collision term poses no problem, this allows one to study the effect of the ultraviolet cutoff in these approximations. This cutoff dependence in the classical approximations of the Boltzmann equation is closely related to the non-renormalizability of the classical statistical approximation of the underlying quantum field theory. The kinetic theory setup that we consider here allows one to study in a much simpler way the dependence on the ultraviolet cutoff, since one has also access to the non-approximated result for comparison.

  4. Properties of the Boltzmann equation in the classical approximation

    SciTech Connect (OSTI)

    Epelbaum, Thomas; Gelis, François; Tanji, Naoto; Wu, Bin

    2014-12-30

    We examine the Boltzmann equation with elastic point-like scalar interactions in two different versions of the the classical approximation. Although solving numerically the Boltzmann equation with the unapproximated collision term poses no problem, this allows one to study the effect of the ultraviolet cutoff in these approximations. This cutoff dependence in the classical approximations of the Boltzmann equation is closely related to the non-renormalizability of the classical statistical approximation of the underlying quantum field theory. The kinetic theory setup that we consider here allows one to study in a much simpler way the dependence on the ultraviolet cutoff, since one has also access to the non-approximated result for comparison.

  5. Properties of the Boltzmann equation in the classical approximation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Epelbaum, Thomas; Gelis, François; Tanji, Naoto; Wu, Bin

    2014-12-30

    We examine the Boltzmann equation with elastic point-like scalar interactions in two different versions of the the classical approximation. Although solving numerically the Boltzmann equation with the unapproximated collision term poses no problem, this allows one to study the effect of the ultraviolet cutoff in these approximations. This cutoff dependence in the classical approximations of the Boltzmann equation is closely related to the non-renormalizability of the classical statistical approximation of the underlying quantum field theory. The kinetic theory setup that we consider here allows one to study in a much simpler way the dependence on the ultraviolet cutoff, since onemore » has also access to the non-approximated result for comparison.« less

  6. Heat transfer system

    DOE Patents [OSTI]

    Not Available

    1980-03-07

    A heat transfer system for a nuclear reactor is described. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

  7. Heat transfer system

    DOE Patents [OSTI]

    McGuire, Joseph C.

    1982-01-01

    A heat transfer system for a nuclear reactor. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

  8. Wound tube heat exchanger

    DOE Patents [OSTI]

    Ecker, Amir L.

    1983-01-01

    What is disclosed is a wound tube heat exchanger in which a plurality of tubes having flattened areas are held contiguous adjacent flattened areas of tubes by a plurality of windings to give a double walled heat exchanger. The plurality of windings serve as a plurality of effective force vectors holding the conduits contiguous heat conducting walls of another conduit and result in highly efficient heat transfer. The resulting heat exchange bundle is economical and can be coiled into the desired shape. Also disclosed are specific embodiments such as the one in which the tubes are expanded against their windings after being coiled to insure highly efficient heat transfer.

  9. Higher-degree linear approximations of nonlinear systems

    SciTech Connect (OSTI)

    Karahan, S.

    1989-01-01

    In this dissertation, the author develops a new method for obtaining higher degree linear approximations of nonlinear control systems. The standard approach in the analysis and synthesis of nonlinear systems is a first order approximation by a linear model. This is usually performed by obtaining a series expansion of the system at some nominal operating point and retaining only the first degree terms in the series. The accuracy of this approximation depends on how far the system moves away from the normal point, and on the relative magnitudes of the higher degree terms in the series expansion. The approximation is achieved by finding an appropriate nonlinear coordinate transformation-feedback pair to perform the higher degree linearization. With the proposed method, one can improve the accuracy of the approximation up to arbitrarily higher degrees, provided certain solvability conditions are satisfied. The Hunt-Su linearizability theorem makes these conditions precise. This approach is similar to Poincare's Normal Form Theorem in formulation, but different in its solution method. After some mathematical background the author derives a set of equations (called the Homological Equations). A solution to this system of linear equations is equivalent to the solution to the problem of approximate linearization. However, it is generally not possible to solve the system of equations exactly. He outlines a method for systematically finding approximate solutions to these equations using singular value decomposition, while minimizing an error with respect to some defined norm.

  10. Current BPA Power Rates (pbl/rates)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and Workshops WP-10 Rate Case WP-07 Rate Case WP-07 Supplemental Rate Case ASC Methodology Adjustments (2007-2009) Adjustments (2002-2006) Previous Rate Cases Financial...

  11. Power Rates Announcements (pbl/rates)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    WP-10 Rate Case WP-07 Rate Case WP-07 Supplemental Rate Case ASC Methodology Adjustments (2007-2009) Adjustments (2002-2006) Previous Rate Cases Financial Choices (2003-06) Power...

  12. Communication: Improved pair approximations in local coupled-cluster methods

    SciTech Connect (OSTI)

    Schwilk, Max; Werner, Hans-Joachim; Usvyat, Denis

    2015-03-28

    In local coupled cluster treatments the electron pairs can be classified according to the magnitude of their energy contributions or distances into strong, close, weak, and distant pairs. Different approximations are introduced for the latter three classes. In this communication, an improved simplified treatment of close and weak pairs is proposed, which is based on long-range cancellations of individually slowly decaying contributions in the amplitude equations. Benchmark calculations for correlation, reaction, and activation energies demonstrate that these approximations work extremely well, while pair approximations based on local second-order Møller-Plesset theory can lead to errors that are 1-2 orders of magnitude larger.

  13. Improved approximate formulas for flux from cylindrical and rectangular sources

    SciTech Connect (OSTI)

    Wallace, O.J.; Bokharee, S.A.

    1993-03-01

    This report provides two new approximate formulas for the flux at detector points outside the radial and axial extensions of a homogeneous cylindrical source and improved approximate formulas for the flux at points opposite rectangular surface sources. These formulas extend the range of geometries for which analytic approximations may be used by shield design engineers to make rapid scoping studies and check more extensive calculations for reasonableness. These formulas can be used to support skeptical, independent evaluations and are also valuable teaching tools for introducing shield designers to complex shield analyses.

  14. Fusion heating technology

    SciTech Connect (OSTI)

    Cole, A.J.

    1982-06-01

    John Lawson established the criterion that in order to produce more energy from fusion than is necessary to heat the plasma and replenish the radiation losses, a minimum value for both the product of plasma density and confinement time t, and the temperature must be achieved. There are two types of plasma heating: neutral beam and electromagnetic wave heating. A neutral beam system is shown. Main development work on negative ion beamlines has focused on the difficult problem of the production of high current sources. The development of a 30 keV-1 ampere multisecond source module is close to being accomplished. In electromagnetic heating, the launcher, which provides the means of coupling the power to the plasma, is most important. The status of heating development is reviewed. Electron cyclotron resonance heating (ECRH), lower hybrid heating (HHH), and ion cyclotron resonance heating (ICRH) are reviewed.

  15. Total Space Heat-

    Gasoline and Diesel Fuel Update (EIA)

    Survey: Energy End-Use Consumption Tables Total Space Heat- ing Cool- ing Venti- lation Water Heat- ing Light- ing Cook- ing Refrig- eration Office Equip- ment Com- puters Other...

  16. ARM - Atmospheric Heat Budget

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    The Atmospheric Heat Budget shows where the atmospheric heat energy comes from and where it goes. Practically all this energy ultimately comes from the sun in the form of the ...

  17. ARM - Heat Index Calculations

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans Heat Index Calculations Heat Index is an index that ...

  18. Electron Heat Transport Measured

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Heat Transport Measured in a Stochastic Magnetic Field T. M. Biewer, * C. B. Forest, ... limit of s &29; 1, RR assumed the electron heat flux to be diffusive, obeying Fourier's ...

  19. Evaluation of Heat Checking and Washout of Heat Resistant Superalloys...

    Office of Scientific and Technical Information (OSTI)

    Evaluation of Heat Checking and Washout of Heat Resistant Superalloys and Coatings for Die inserts Citation Details In-Document Search Title: Evaluation of Heat Checking and ...

  20. Buildings","All Buildings with Water Heating","Water-Heating...

    U.S. Energy Information Administration (EIA) Indexed Site

    5. Water-Heating Energy Sources, Number of Buildings, 1999" ,"Number of Buildings (thousand)" ,"All Buildings","All Buildings with Water Heating","Water-Heating Energy Sources Used ...

  1. Consolidated Electric Cooperative- Heat Pump and Water Heating Rebates

    Office of Energy Efficiency and Renewable Energy (EERE)

    Consolidated Electric Cooperative provides rebates to residential customers who install electric water heaters, dual-fuel heating system or geothermal heat pumps. A dual-fuel heating systems...

  2. HEATING 7. 1 user's manual

    SciTech Connect (OSTI)

    Childs, K.W.

    1991-07-01

    HEATING is a FORTRAN program designed to solve steady-state and/or transient heat conduction problems in one-, two-, or three- dimensional Cartesian, cylindrical, or spherical coordinates. A model may include multiple materials, and the thermal conductivity, density, and specific heat of each material may be both time- and temperature-dependent. The thermal conductivity may be anisotropic. Materials may undergo change of phase. Thermal properties of materials may be input or may be extracted from a material properties library. Heating generation rates may be dependent on time, temperature, and position, and boundary temperatures may be time- and position-dependent. The boundary conditions, which may be surface-to-boundary or surface-to-surface, may be specified temperatures or any combination of prescribed heat flux, forced convection, natural convection, and radiation. The boundary condition parameters may be time- and/or temperature-dependent. General graybody radiation problems may be modeled with user-defined factors for radiant exchange. The mesh spacing may be variable along each axis. HEATING is variably dimensioned and utilizes free-form input. Three steady-state solution techniques are available: point-successive-overrelaxation iterative method with extrapolation, direct-solution (for one-dimensional or two-dimensional problems), and conjugate gradient. Transient problems may be solved using one of several finite-difference schemes: Crank-Nicolson implicit, Classical Implicit Procedure (CIP), Classical Explicit Procedure (CEP), or Levy explicit method (which for some circumstances allows a time step greater than the CEP stability criterion). The solution of the system of equations arising from the implicit techniques is accomplished by point-successive-overrelaxation iteration and includes procedures to estimate the optimum acceleration parameter.

  3. Abrasion resistant heat pipe

    DOE Patents [OSTI]

    Ernst, Donald M. (Leola, PA)

    1984-10-23

    A specially constructed heat pipe for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.

  4. Abrasion resistant heat pipe

    DOE Patents [OSTI]

    Ernst, D.M.

    1984-10-23

    A specially constructed heat pipe is described for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.

  5. Solar heat receiver

    DOE Patents [OSTI]

    Hunt, Arlon J.; Hansen, Leif J.; Evans, David B.

    1985-01-01

    A receiver for converting solar energy to heat a gas to temperatures from 700.degree.-900.degree. C. The receiver is formed to minimize impingement of radiation on the walls and to provide maximum heating at and near the entry of the gas exit. Also, the receiver is formed to provide controlled movement of the gas to be heated to minimize wall temperatures. The receiver is designed for use with gas containing fine heat absorbing particles, such as carbon particles.

  6. Solar heat receiver

    DOE Patents [OSTI]

    Hunt, A.J.; Hansen, L.J.; Evans, D.B.

    1982-09-29

    A receiver is described for converting solar energy to heat a gas to temperatures from 700 to 900/sup 0/C. The receiver is formed to minimize impingement of radiation on the walls and to provide maximum heating at and near the entry of the gas exit. Also, the receiver is formed to provide controlled movement of the gas to be heated to minimize wall temperatures. The receiver is designed for use with gas containing fine heat absorbing particles, such as carbon particles.

  7. Residential heating oil price

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 7.6 cents from a week ago to $2.97 per gallon. That's down $1.05 from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $2.94 per gallon, down 6.7 cents from last week, and down $1.07

  8. Residential heating oil price

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 6.3 cents from a week ago to $2.91 per gallon. That's down $1.10 from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $2.88 per gallon, down 6.8 cents from last week, and down $1.13

  9. Residential heating oil price

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 7.5 cents from a week ago to $2.84 per gallon. That's down $1.22 from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $2.80 per gallon, down 7.4 cents from last week, and down $1.23

  10. Residential heating oil price

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 4.1 cents from a week ago to $2.89 per gallon, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $2.84 per gallon, down 5.4 cents from last week

  11. Residential heating oil price

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 3.6 cents from a week ago to $3.04 per gallon. That's down 99.4 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $3.01 per gallon, down 3.6 cents from last week, and down $1.01

  12. MA HEAT Loan Overview

    Broader source: Energy.gov [DOE]

    Presents information on the success of Massachusetts's HEAT loan offerings and how the financing tool is funded.

  13. Heat pipes for industrial waste heat recovery

    SciTech Connect (OSTI)

    Merrigan, M.A.

    1981-01-01

    Development work on the high temperature ceramic recuperator at Los Alamos National Laboratory is described and involved material investigations, fabrication methods development, compatibility tests, heat pipe operation, and the modeling of application conditions based on current industrial usage. Solid ceramic heat pipes, ceramic coated refractory pipes, and high-temperature oxide protected metallic pipes have been investigated. Economic studies of the use of heat-pipe based recuperators in industrial furnaces have been conducted and payback periods determined as a function of material, fabrication, and installation cost.

  14. Broadband Heating Rate Profile Project (BBHRP) - SGP ripbe370mcfarlane...

    Office of Scientific and Technical Information (OSTI)

    Additionally, an interface between the RIPBE input file and the RRTM was developed using the new ARM integrated software development environment (ISDE) and effort was put into ...

  15. Broadband Heating Rate Profile Project (BBHRP) - SGP ripbe1mcfarlane...

    Office of Scientific and Technical Information (OSTI)

    Additionally, an interface between the RIPBE input file and the RRTM was developed using the new ARM integrated software development environment (ISDE) and effort was put into ...

  16. Property:Heat Recovery Rating | Open Energy Information

    Open Energy Info (EERE)

    + 2,000 + Distributed Generation StudyPatterson Farms CHP System Using Renewable Biogas + 1,366,072 + Distributed Generation StudySUNY Buffalo + 600,000 + Distributed...

  17. ARM - Evaluation Product - Broadband Heating Rate Profile Project...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    information on the BBHRP output files so that analysis of the output would be more straightforward. This new version of BBHRP, sgp1bbhrpripbeC1.c1, uses the RIPBE files as input to...

  18. Cloud Properties and Radiative Heating Rates for TWP (Dataset...

    Office of Scientific and Technical Information (OSTI)

    This Combined Remote Sensor Retrieval Algorithm (CombRet) produces vertical profiles of liquid or ice water content (LWC or IWC), droplet effective radius (re), ice crystal ...

  19. Integral approximations to classical diffusion and smoothed particle hydrodynamics

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Du, Qiang; Lehoucq, R. B.; Tartakovsky, A. M.

    2014-12-31

    The contribution of the paper is the approximation of a classical diffusion operator by an integral equation with a volume constraint. A particular focus is on classical diffusion problems associated with Neumann boundary conditions. By exploiting this approximation, we can also approximate other quantities such as the flux out of a domain. Our analysis of the model equation on the continuum level is closely related to the recent work on nonlocal diffusion and peridynamic mechanics. In particular, we elucidate the role of a volumetric constraint as an approximation to a classical Neumann boundary condition in the presence of physical boundary.more » The volume-constrained integral equation then provides the basis for accurate and robust discretization methods. As a result, an immediate application is to the understanding and improvement of the Smoothed Particle Hydrodynamics (SPH) method.« less

  20. Second post-Newtonian approximation of Einstein-aether theory

    SciTech Connect (OSTI)

    Xie Yi; Huang Tianyi

    2008-06-15

    In this paper, second post-Newtonian approximation of Einstein-aether theory is obtained by Chandrasekhar's approach. Five parametrized post-Newtonian parameters in first post-Newtonian approximation are presented after a time transformation and they are identical with previous works, in which {gamma}=1, {beta}=1, and two preferred-frame parameters remain. Meanwhile, in second post-Newtonian approximation, a parameter, which represents third order nonlinearity for gravity, is zero--the same as in general relativity. For an application for future deep space laser ranging missions, we reduce the metric coefficients for light propagation in a case of N point masses as a simplified model of the Solar System. The resulting light deflection angle in second post-Newtonian approximation poses another constraint on the Einstein-aether theory.

  1. Exact and approximate Kohn-Sham potentials in ensemble density...

    Office of Scientific and Technical Information (OSTI)

    Title: Exact and approximate Kohn-Sham potentials in ensemble density-functional theory Authors: Yang, Zeng-hui ; Trail, John R. ; Pribram-Jones, Aurora ; Burke, Kieron ; Needs, ...

  2. Liquid heat capacity lasers

    DOE Patents [OSTI]

    Comaskey, Brian J.; Scheibner, Karl F.; Ault, Earl R.

    2007-05-01

    The heat capacity laser concept is extended to systems in which the heat capacity lasing media is a liquid. The laser active liquid is circulated from a reservoir (where the bulk of the media and hence waste heat resides) through a channel so configured for both optical pumping of the media for gain and for light amplification from the resulting gain.

  3. HEAT TRANSFER MEANS

    DOE Patents [OSTI]

    Fraas, A.P.; Wislicenus, G.F.

    1961-07-11

    A heat exchanger is adapted to unifomly cool a spherical surface. Equations for the design of a spherical heat exchanger hav~g tubes with a uniform center-to-center spining are given. The heat exchanger is illustrated in connection with a liquid-fueled reactor.

  4. Waste Heat Recovery

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    - PRE-DECISIONAL - DRAFT 1 Waste Heat Recovery 1 Technology Assessment 2 Contents 3 1. Introduction to the Technology/System ............................................................................................... 2 4 1.1. Introduction to Waste Heat Recovery .......................................................................................... 2 5 1.2. Challenges and Barriers for Waste Heat Recovery ..................................................................... 13 6 1.3. Public

  5. Heat pipe effect in porous medium

    SciTech Connect (OSTI)

    Joseph, M.

    1992-12-01

    In this thesis a parametric study of the thermal and hydrologic characteristics of the fractured porous tuffs at Yucca Mountain, Nevada was conducted. The effects of different fracture and matrix properties including permeability, thermal conductivity, specific heat, porosity, and tortuosity on heat pipe performance in the vicinity of the waste package were observed. Computer simulations were carried out using TOUGH code on a Cray YMP-2 supercomputer. None of the fracture parameters affected the heat pipe performance except the mobility of the liquid in the fracture. Matrix permeability and thermal conductivity were found to have significant effect on the heat pipe performance. The effect of mass injection was studied for liquid water and air injected at the fracture boundary. A high rate of mass injection was required to produce any effect on the heat pipe. The fracture-matrix equilibrium is influenced by the matrix permeability and the matrix thermal conductivity.

  6. Control system for fluid heated steam generator

    DOE Patents [OSTI]

    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.

  7. Control system for fluid heated steam generator

    DOE Patents [OSTI]

    Boland, James F.; Koenig, John F.

    1985-01-01

    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.

  8. Port Graham Biomass Community Heat Project

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Sink, Chugachmiut Recipient Principal Investigator For Port Graham Village Council US Department of Energy Office of Indian Energy & Economic Development-May 5, 2015 Port Graham population of 177 (2010 Census) Southern tip of Kenai Peninsula, about 28-miles off the road system from Homer, Alaska, accessible by air or water only Unemployment rate 22%; 44.6% out of labor force; Median household income $18,942 Heat 5-community buildings with cord wood biomass heating system Displace

  9. A corrosive resistant heat exchanger

    DOE Patents [OSTI]

    Richlen, S.L.

    1987-08-10

    A corrosive and erosive resistant heat exchanger which recovers heat from a contaminated heat stream. The heat exchanger utilizes a boundary layer of innocuous gas, which is continuously replenished, to protect the heat exchanger surface from the hot contaminated gas. The innocuous gas is pumped through ducts or perforations in the heat exchanger wall. Heat from the heat stream is transferred by radiation to the heat exchanger wall. Heat is removed from the outer heat exchanger wall by a heat recovery medium. 3 figs., 3 tabs.

  10. Solar Process Heat Basics | NREL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Solar Process Heat Basics Commercial and industrial buildings may use the same solar technologies-photovoltaics, passive heating, daylighting, and water heating-that are used for ...

  11. Geothermal Heat Pump Manufacturing Activities

    Gasoline and Diesel Fuel Update (EIA)

    defined as geothermal heat pump unit with all the necessary functional components, except for installation materials. These include geothermal heat pump, air handler, heat ...

  12. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, Gershon; Perez-Blanco, Horacio

    1984-01-01

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  13. Heat recovery casebook

    SciTech Connect (OSTI)

    Lawn, J.

    1980-10-01

    Plants and factories could apply a great variety of sources and uses for valuable waste heat. Applications may be evaluated on the basis of real use for a specific waste heat, high-enough temperature and quality of work, and feasibility of mechanical heat transfer method. Classification may be by temperature, application, heat-transfer equipment, etc. Many buildings and industrial processes lend themselves well to heat-recovery strategies. Five case histories describe successful systems used by the Continental Corporation Data Center; Nabisco, Inc.; Kasper Foundry Company; Seven Up Bottling Company of Indiana; and Lehr Precision Tool company. (DCK)

  14. Current Power Rates

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases Rate Information Current Power Rates Current Transmission Rates...

  15. Current Transmission Rates

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases Rate Information Current Power Rates Current Transmission Rates...

  16. Previous Power Rates

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases Rate Information Current Power Rates Current Transmission Rates...

  17. Previous Transmission Rates

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases Rate Information Current Power Rates Current Transmission Rates...

  18. Heat Transfer Fluids for Solar Water Heating Systems | Department...

    Broader source: Energy.gov (indexed) [DOE]

    Illustration of a solar water heater. Illustration of a solar water heater. Heat-transfer fluids carry heat through solar collectors and a heat exchanger to the heat storage tanks...

  19. Heat pump apparatus

    DOE Patents [OSTI]

    Nelson, Paul A.; Horowitz, Jeffrey S.

    1983-01-01

    A heat pump apparatus including a compact arrangement of individual tubular reactors containing hydride-dehydride beds in opposite end sections, each pair of beds in each reactor being operable by sequential and coordinated treatment with a plurality of heat transfer fluids in a plurality of processing stages, and first and second valves located adjacent the reactor end sections with rotatable members having multiple ports and associated portions for separating the hydride beds at each of the end sections into groups and for simultaneously directing a plurality of heat transfer fluids to the different groups. As heat is being generated by a group of beds, others are being regenerated so that heat is continuously available for space heating. As each of the processing stages is completed for a hydride bed or group of beds, each valve member is rotated causing the heat transfer fluid for the heat processing stage to be directed to that bed or group of beds. Each of the end sections are arranged to form a closed perimeter and the valve member may be rotated repeatedly about the perimeter to provide a continuous operation. Both valves are driven by a common motor to provide a coordinated treatment of beds in the same reactors. The heat pump apparatus is particularly suitable for the utilization of thermal energy supplied by solar collectors and concentrators but may be used with any source of heat, including a source of low-grade heat.

  20. Active microchannel heat exchanger

    DOE Patents [OSTI]

    Tonkovich, Anna Lee Y. [Pasco, WA; Roberts, Gary L. [West Richland, WA; Call, Charles J. [Pasco, WA; Wegeng, Robert S. [Richland, WA; Wang, Yong [Richland, WA

    2001-01-01

    The present invention is an active microchannel heat exchanger with an active heat source and with microchannel architecture. The microchannel heat exchanger has (a) an exothermic reaction chamber; (b) an exhaust chamber; and (c) a heat exchanger chamber in thermal contact with the exhaust chamber, wherein (d) heat from the exothermic reaction chamber is convected by an exothermic reaction exhaust through the exhaust chamber and by conduction through a containment wall to the working fluid in the heat exchanger chamber thereby raising a temperature of the working fluid. The invention is particularly useful as a liquid fuel vaporizer and/or a steam generator for fuel cell power systems, and as a heat source for sustaining endothermic chemical reactions and initiating exothermic reactions.

  1. SU-E-T-196: Heat Diffusion Modeling for Digital Holographic Interferometry Dosimetry

    SciTech Connect (OSTI)

    Cavan, A; Meyer, J

    2014-06-01

    Purpose: We have previously demonstrated that with Digital Holographic Interferometry (DHI) 2D spatial calorimetric measurements of high dose rate radiation sources can be obtained. The impact of heat transfer must be considered when undertaking any form of calorimetric measurement, as the radiation induced temperature distributions are subject to degradation due to heat diffusion. Unaccounted for, this limits the accuracy of the approach especially for long delivery times. Methods: 3D modelling of the heat diffusion in water was undertaken, and two different approaches developed to account for this effect. The mathematical framework to describe heat diffusion in 3D was applied, with the differential equations solved numerically using an implicit method. The first approach involved the comparison of the DHI measurements to an independent dose model of the source. The model was forward modeled to account for the heat diffusion during irradiation, allowing a direct comparison to validate the measured results. The second approach involved the correction of the measured data directly, by comparing the temperature distribution of two instances and subtracting the effects of heat diffusion of the first distribution from the second instance. This required the use of the Abel transform to approximate the 3D dose distribution from the 2D DHI results, thus limiting the approach to radiation applications possessing cylindrical symmetry. Results: The first approach resulted in higher accuracy and was more straightforward, but has a major limitation in that the measured results are only able to be utilized in comparison with an independent dose model. The applicability of the second approach is affected by noise in the measurement data and introduces higher uncertainties, but results in higher usability of the final data. Conclusion: Both approaches were implemented, and if used in conjunction would provide the most utility for the interpretation and use of DHI measurements.

  2. ACHILLES: Heat Transfer in PWR Core During LOCA Reflood Phase

    Energy Science and Technology Software Center (OSTI)

    2013-11-01

    1. NAME AND TITLE OF DATA LIBRARY ACHILLES -Heat Transfer in PWR Core During LOCA Reflood Phase. 2. NAME AND TITLE OF DATA RETRIEVAL PROGRAMS N/A 3. CONTRIBUTOR AEA Technology, Winfrith Technology Centre, Dorchester DT2 8DH United Kingdom through the OECD Nuclear Energy Agency Data Bank, Issy-les-Moulineaux, France. 4. DESCRIPTION OF TEST FACILITY The most important features of the Achilles rig were the shroud vessel, which contained the test section, and the downcomer. These maymore » be thought of as representing the core barrel and the annular downcomer in the reactor pressure vessel. The test section comprises a cluster of 69 rods in a square array within a circular shroud vessel. The rod diameter and pitch (9.5 mm and 12.6 mm) were typical of PWR dimensions. The internal diameter of the shroud vessel was 128 mm. Each rod was electrically heated over a length of 3.66 m, which is typical of the nuclear heated length in a PWR fuel rod, and each contained 6 internal thermocouples. These were arranged in one of 8 groupings which concentrated the thermocouples in different axial zones. The spacer grids were at prototypic PWR locations. Each grid had two thermocouples attached to its trailing edge at radial locations. The axial power profile along the rods was an 11 step approximation to a "chopped cosine". The shroud vessel had 5 heating zones whose power could be independently controlled. 5. DESCRIPTION OF TESTS The Achilles experiments investigated the heat transfer in the core of a Pressurized Water Reactor during the re-flood phase of a postulated large break loss of coolant accident. The results provided data to validate codes and to improve modeling. Different types of experiments were carried out which included single phase cooling, re-flood under low flow conditions, level swell and re-flood under high flow conditions. Three series of experiments were performed. The first and the third used the same test section but the second used another test section

  3. ACHILLES: Heat Transfer in PWR Core During LOCA Reflood Phase

    SciTech Connect (OSTI)

    2013-11-01

    1. NAME AND TITLE OF DATA LIBRARY ACHILLES -Heat Transfer in PWR Core During LOCA Reflood Phase. 2. NAME AND TITLE OF DATA RETRIEVAL PROGRAMS N/A 3. CONTRIBUTOR AEA Technology, Winfrith Technology Centre, Dorchester DT2 8DH United Kingdom through the OECD Nuclear Energy Agency Data Bank, Issy-les-Moulineaux, France. 4. DESCRIPTION OF TEST FACILITY The most important features of the Achilles rig were the shroud vessel, which contained the test section, and the downcomer. These may be thought of as representing the core barrel and the annular downcomer in the reactor pressure vessel. The test section comprises a cluster of 69 rods in a square array within a circular shroud vessel. The rod diameter and pitch (9.5 mm and 12.6 mm) were typical of PWR dimensions. The internal diameter of the shroud vessel was 128 mm. Each rod was electrically heated over a length of 3.66 m, which is typical of the nuclear heated length in a PWR fuel rod, and each contained 6 internal thermocouples. These were arranged in one of 8 groupings which concentrated the thermocouples in different axial zones. The spacer grids were at prototypic PWR locations. Each grid had two thermocouples attached to its trailing edge at radial locations. The axial power profile along the rods was an 11 step approximation to a "chopped cosine". The shroud vessel had 5 heating zones whose power could be independently controlled. 5. DESCRIPTION OF TESTS The Achilles experiments investigated the heat transfer in the core of a Pressurized Water Reactor during the re-flood phase of a postulated large break loss of coolant accident. The results provided data to validate codes and to improve modeling. Different types of experiments were carried out which included single phase cooling, re-flood under low flow conditions, level swell and re-flood under high flow conditions. Three series of experiments were performed. The first and the third used the same test section but the second used another test section, similar in

  4. Subsurface heaters with low sulfidation rates

    DOE Patents [OSTI]

    John, Randy Carl; Vinegar, Harold J

    2013-12-10

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

  5. Variational principles with Pad approximants for tearing mode analysis

    SciTech Connect (OSTI)

    Cole, Andrew J.; Finn, John M.

    2014-03-15

    Tearing modes occur in several distinct physical regimes, and it is often important to compute the inner layer response for these modes with various effects. There is a need for an approximate and efficient method of solving the inner layer equations in all these regimes. In this paper, we introduce a method of solving the inner layer equations based on using a variational principle with Pad approximants. For all the regimes considered, the main layer equations to be solved are inhomogeneous, and Pad approximants give a convenient and efficient method of satisfying the correct asymptotic behavior at the edge of the layer. Results using this variational principlePad approximant method in three of these regimes is presented. These regimes are the constant-? resistive-inertial (RI) regime, the constant-? viscoresistive regime, and the non-constant-? inviscid tearing regime. The last regime includes the constant-? RI regime and the inertial regime. The results show that reasonable accuracy can be obtained very efficiently with Pad approximants having a small number of parameters.

  6. Fourier heat conduction as a phenomenon described within the scope of the second law

    SciTech Connect (OSTI)

    Jesudason, Christopher G.

    2014-12-10

    unfortunately linked to mechanical reversibility, that has discouraged such an association. The modeling is based on an application of a 'recoverable transition', defined and developed earlier on ideas derived from thermal desorption of particles from a surface where the Fourier heat conduction process is approximated as a series of such desorption processes. We recall that the original Carnot engine required both adiabatic and isothermal steps to complete the zero entropy cycle, and this construct lead to the consequent deduction that any Second law statement that refers to heat-work conversion processes are only globally relevant. Here, on the other hand, we examine Fourier heat conduction from MD simulation and model this process as a zero-entropy forward scattering process relative to each of the atoms in the lattice chain being treated as a system where the Carnot cycle can be applied individually. The equations developed predicts the 'work' done to be equal to the energy transfer rate. The MD simulations conducted shows excellent agreement with the theory. Such views and results as these, if developed to a successful conclusion could imply that the Carnot cycle be viewed as describing a local process of energy-work conversion and that irreversible local processes might be brought within the scope of this cycle, implying a unified treatment of thermodynamically (i) irreversible, (ii) reversible, (iii) isothermal and (iv) adiabatic processes.

  7. Geothermal Heat Pump Manufacturing Activities

    Gasoline and Diesel Fuel Update (EIA)

    ARI-320 Water-Source Heat Pumps 10 ARI-325 Ground Water-Source Heat Pumps 13 ARI-330 Ground Source Closed-Loop Heat Pumps 11 ARI-870 Direct Geoexhange Heat Pumps 2 Other Non-ARI ...

  8. Foundation heat exchangers for residential ground source heat pump systems Numerical modeling and experimental validation

    SciTech Connect (OSTI)

    Xing, Lu; Cullin, James; Spitler, Jeffery; Im, Piljae; Fisher, Daniel

    2011-01-01

    A new type of ground heat exchanger that utilizes the excavation often made for basements or foundations has been proposed as an alternative to conventional ground heat exchangers. This article describes a numerical model that can be used to size these foundation heat exchanger (FHX) systems. The numerical model is a two-dimensional finite-volume model that considers a wide variety of factors, such as soil freezing and evapotranspiration. The FHX numerical model is validated with one year of experimental data collected at an experimental house located near Oak Ridge, Tennessee. The model shows good agreement with the experimental data-heat pump entering fluid temperatures typically within 1 C (1.8 F) - with minor discrepancies due to approximations, such as constant moisture content throughout the year, uniform evapotranspiration over the seasons, and lack of ground shading in the model.

  9. Heat pump system

    DOE Patents [OSTI]

    Swenson, Paul F.; Moore, Paul B.

    1983-01-01

    An air heating and cooling system for a building includes an expansion type refrigeration circuit and a vapor power circuit. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The vapor power circuit includes two heat exchangers, one of which is disposed in series air flow relationship with the indoor refrigeration circuit heat exchanger and the other of which is disposed in series air flow relationship with the outdoor refrigeration circuit heat exchanger. Fans powered by electricity generated by a vapor power circuit alternator circulate indoor air through the two indoor heat exchangers and circulate outside air through the two outdoor heat exchangers. The system is assembled as a single roof top unit, with a vapor power generator and turbine and compressor thermally insulated from the heat exchangers, and with the indoor heat exchangers thermally insulated from the outdoor heat exchangers.

  10. Heat pump system

    DOE Patents [OSTI]

    Swenson, Paul F.; Moore, Paul B.

    1977-01-01

    An air heating and cooling system for a building includes an expansion type refrigeration circuit and a vapor power circuit. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The vapor power circuit includes two heat exchangers, one of which is disposed in series air flow relationship with the indoor refrigeration circuit heat exchanger and the other of which is disposed in series air flow relationship with the outdoor refrigeration circuit heat exchanger. Fans powered by electricity generated by a vapor power circuit alternator circulate indoor air through the two indoor heat exchangers and circulate outside air through the two outdoor heat exchangers. The system is assembled as a single roof top unit, with a vapor power generator and turbine and compressor thermally insulated from the heat exchangers, and with the indoor heat exchangers thermally insulated from the outdoor heat exchangers.

  11. Heat pump system

    DOE Patents [OSTI]

    Swenson, Paul F.; Moore, Paul B.

    1983-06-21

    An air heating and cooling system for a building includes an expansion type refrigeration circuit and a vapor power circuit. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The vapor power circuit includes two heat exchangers, one of which is disposed in series air flow relationship with the indoor refrigeration circuit heat exchanger and the other of which is disposed in series air flow relationship with the outdoor refrigeration circuit heat exchanger. Fans powered by electricity generated by a vapor power circuit alternator circulate indoor air through the two indoor heat exchangers and circulate outside air through the two outdoor heat exchangers. The system is assembled as a single roof top unit, with a vapor power generator and turbine and compressor thermally insulated from the heat exchangers, and with the indoor heat exchangers thermally insulated from the outdoor heat exchangers.

  12. Approximate Bisimulation-Based Reduction of Power System Dynamic Models

    SciTech Connect (OSTI)

    Stankovic, AM; Dukic, SD; Saric, AT

    2015-05-01

    In this paper we propose approximate bisimulation relations and functions for reduction of power system dynamic models in differential- algebraic (descriptor) form. The full-size dynamic model is obtained by linearization of the nonlinear transient stability model. We generalize theoretical results on approximate bisimulation relations and bisimulation functions, originally derived for a class of constrained linear systems, to linear systems in descriptor form. An algorithm for transient stability assessment is proposed and used to determine whether the power system is able to maintain the synchronism after a large disturbance. Two benchmark power systems are used to illustrate the proposed algorithm and to evaluate the applicability of approximate bisimulation relations and bisimulation functions for reduction of the power system dynamic models.

  13. Fokker-Planck approximation of monoenergetic transport processes

    SciTech Connect (OSTI)

    Boergers, C.; Larsen, E.W.

    1994-12-31

    For transport problems with highly forward-peaked scattering, the transport equation is often approximated by the Fokker-Planck equation or, if large-angle scattering is deemed sufficiently important, by the Boltzmann-Fokker-Planck equation. In this paper, we state a simple, necessary, and sufficient condition for the validity of the simpler Fokker-Planck approximation for monoenergetic particle transport. We also show that for screened Rutherford scattering, the Fokker-Planck approximation is only marginally valid and is inaccurate unless the scattering is extremely forward peaked. (The same is true for more sophisticated models of elastic scattering of charged particles. In this paper, we restrict ourselves to screened Rutherford scattering for simplicity). More details on the results presented here will be given in forthcoming publications.

  14. PNCA-02 Rate Case (rates/ratecases)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Proposed Adjustment to the Rate for Interchange Energy Imbalances Under the Pacific Northwest Coordination Agreement (PNCA-02 Rate Case) (updated on April 26, 2002) BPA has issued...

  15. ARM - PI Product - Combined Retrieval, Microphysical Retrievals & Heating

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Rates ProductsCombined Retrieval, Microphysical Retrievals & Heating Rates ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Combined Retrieval, Microphysical Retrievals & Heating Rates [ research data - ASR funded ] The PNNL Combined Remote Sensor retrieval algorithm (CombRet) is designed to retrieve cloud and precipitation properties for all sky conditions. The retrieval is based on a

  16. Potential vertical movement of large heat-generating waste packages in salt.

    SciTech Connect (OSTI)

    Clayton, Daniel James; Martinez, Mario J.; Hardin, Ernest L.

    2013-05-01

    With renewed interest in disposal of heat-generating waste in bedded or domal salt formations, scoping analyses were conducted to estimate rates of waste package vertical movement. Vertical movement is found to result from thermal expansion, from upward creep or heave of the near-field salt, and from downward buoyant forces on the waste package. A two-pronged analysis approach was used, with thermal-mechanical creep modeling, and coupled thermal-viscous flow modeling. The thermal-mechanical approach used well-studied salt constitutive models, while the thermal-viscous approach represented the salt as a highly viscous fluid. The Sierra suite of coupled simulation codes was used for both approaches. The waste package in all simulations was a right-circular cylinder with the density of steel, in horizontal orientation. A time-decaying heat generation function was used to represent commercial spent fuel with typical burnup and 50-year age. Results from the thermal-mechanical base case showed approximately 27 cm initial uplift of the package, followed by gradual relaxation closely following the calculated temperature history. A similar displacement history was obtained with the package density set equal to that of salt. The slight difference in these runs is attributable to buoyant displacement (sinking) and is on the order of 1 mm in 2,000 years. Without heat generation the displacement stabilizes at a fraction of millimeter after a few hundred years. Results from thermal-viscous model were similar, except that the rate of sinking was constant after cooldown, at approximately 0.15 mm per 1,000 yr. In summary, all calculations showed vertical movement on the order of 1 mm or less in 2,000 yr, including calculations using well-established constitutive models for temperature-dependent salt deformation. Based on this finding, displacement of waste packages in a salt repository is not a significant repository performance issue.

  17. On the approximation of crack shapes found during inservice inspection

    SciTech Connect (OSTI)

    Bhate, S.R.; Chawla, D.S.; Kushwaha, H.S.

    1997-04-01

    This paper addresses the characterization of axial internal flaw found during inservice inspection of a pipe. J-integral distribution for various flaw shapes is obtained using line spring finite, element method. The peak J-value and its distribution across the crack is found to be characteristic feature of each shape. The triangular shape yields peak J-value away from the center, the point of depth. The elliptic approximation results in large overestimate of J-value for unsymmetric flaws. Triangular approximation is recommended for such flaws so that further service can be obtained from the component.

  18. Enhanced convective and film boiling heat transfer by surface gas injection

    SciTech Connect (OSTI)

    Duignan, M.R.; Greene, G.A. ); Irvine, T.F., Jr. . Dept. of Mechanical Engineering)

    1992-04-01

    Heat transfer measurements were made for stable film boiling of water over a horizontal, flat stainless steel plate from the minimum film boiling point temperature, T{sub SURFACE} {approximately}500K, to T{sub SURFACE} {approximately}950K. The pressure at the plate was approximately 1 atmosphere and the temperature of the water pool was maintained at saturation. The data were compared to the Berenson film-boiling model, which was developed for minimum film-boiling-point conditions. The model accurately represented the data near the minimum film-boiling point and at the highest temperatures measured, as long it was corrected for the heat transferred by radiation. On the average, the experimental data lay within {plus minus}7% of the model. Measurements of heat transfer were made without film boiling for nitrogen jetting into an overlying pool of water from nine 1-mm- diameter holes, drilled in the heat transfer plate. The heat flux was maintained constant at approximately 26.4 kW/m{sup 2}. For water-pool heights of less than 6cm the heat transfer coefficient deceased linearly with a decrease in heights. Above 6cm the heat transfer coefficient was unaffected. For the entire range of gas velocities measured (0 to 8.5 cm/s), the magnitude of the magnitude of the heat transfer coefficient only changed by approximately 20%. The heat transfer data bound the Konsetov model for turbulent pool heat transfer which was developed for vertical heat transfer surfaces. This agreement suggests that surface orientation may not be important when the gas jets do not locally affect the surface heat transfer. Finally, a database was developed for heat transfer from the plate with both film boiling and gas jetting occurring simultaneously, in a pool of water maintained at its saturation temperature. The effect of passing nitrogen through established film boiling is to increase the heat transfer from that surface. 60 refs.

  19. Enhanced convective and film boiling heat transfer by surface gas injection

    SciTech Connect (OSTI)

    Duignan, M.R.; Greene, G.A.; Irvine, T.F., Jr.

    1992-04-01

    Heat transfer measurements were made for stable film boiling of water over a horizontal, flat stainless steel plate from the minimum film boiling point temperature, T{sub SURFACE} {approximately}500K, to T{sub SURFACE} {approximately}950K. The pressure at the plate was approximately 1 atmosphere and the temperature of the water pool was maintained at saturation. The data were compared to the Berenson film-boiling model, which was developed for minimum film-boiling-point conditions. The model accurately represented the data near the minimum film-boiling point and at the highest temperatures measured, as long it was corrected for the heat transferred by radiation. On the average, the experimental data lay within {plus_minus}7% of the model. Measurements of heat transfer were made without film boiling for nitrogen jetting into an overlying pool of water from nine 1-mm- diameter holes, drilled in the heat transfer plate. The heat flux was maintained constant at approximately 26.4 kW/m{sup 2}. For water-pool heights of less than 6cm the heat transfer coefficient deceased linearly with a decrease in heights. Above 6cm the heat transfer coefficient was unaffected. For the entire range of gas velocities measured [0 to 8.5 cm/s], the magnitude of the magnitude of the heat transfer coefficient only changed by approximately 20%. The heat transfer data bound the Konsetov model for turbulent pool heat transfer which was developed for vertical heat transfer surfaces. This agreement suggests that surface orientation may not be important when the gas jets do not locally affect the surface heat transfer. Finally, a database was developed for heat transfer from the plate with both film boiling and gas jetting occurring simultaneously, in a pool of water maintained at its saturation temperature. The effect of passing nitrogen through established film boiling is to increase the heat transfer from that surface. 60 refs.

  20. Cold Climate Heat Pumps Using Tandem Compressors

    SciTech Connect (OSTI)

    Shen, Bo; Abdelaziz, Omar; Rice, C Keith; Baxter, Van D

    2016-01-01

    In cold climate zones, e.g. ASHRAE climate regions IV and V, conventional electric air-source heat pumps (ASHP) do not work well, due to high compressor discharge temperatures, large pressure ratios and inadequate heating capacities at low ambient temperatures. Consequently, significant use of auxiliary strip heating is required to meet the building heating load. We introduce innovative ASHP technologies as part of continuing efforts to eliminate auxiliary strip heat use and maximize heating COP with acceptable cost-effectiveness and reliability. These innovative ASHP were developed using tandem compressors, which are capable of augmenting heating capacity at low temperatures and maintain superior part-load operation efficiency at moderate temperatures. Two options of tandem compressors were studied; the first employs two identical, single-speed compressors, and the second employs two identical, vapor-injection compressors. The investigations were based on system modeling and laboratory evaluation. Both designs have successfully met the performance criteria. Laboratory evaluation showed that the tandem, single-speed compressor ASHP system is able to achieve heating COP = 4.2 at 47 F (8.3 C), COP = 2.9 at 17 F (-8.3 C), and 76% rated capacity and COP = 1.9 at -13 F (-25 C). This yields a HSPF = 11.0 (per AHRI 210/240). The tandem, vapor-injection ASHP is able to reach heating COP = 4.4 at 47 F, COP = 3.1 at 17 F, and 88% rated capacity and COP = 2.0 at -13 F. This yields a HSPF = 12.0. The system modeling and further laboratory evaluation are presented in the paper.

  1. On how differently the quasi-harmonic approximation works for two isostructural crystals: Thermal properties of periclase and lime

    SciTech Connect (OSTI)

    Erba, A. Dovesi, R.; Shahrokhi, M.; Moradian, R.

    2015-01-28

    Harmonic and quasi-harmonic thermal properties of two isostructural simple oxides (periclase, MgO, and lime, CaO) are computed with ab initio periodic simulations based on the density-functional-theory (DFT). The more polarizable character of calcium with respect to magnesium cations is found to dramatically affect the validity domain of the quasi-harmonic approximation that, for thermal structural properties (such as temperature dependence of volume, V(T), bulk modulus, K(T), and thermal expansion coefficient, α(T)), reduces from [0 K-1000 K] for MgO to just [0 K-100 K] for CaO. On the contrary, thermodynamic properties (such as entropy, S(T), and constant-volume specific heat, C{sub V}(T)) are described reliably at least up to 2000 K and quasi-harmonic constant-pressure specific heat, C{sub P}(T), up to about 1000 K in both cases. The effect of the adopted approximation to the exchange-correlation functional of the DFT is here explicitly investigated by considering five different expressions of three different classes (local-density approximation, generalized-gradient approximation, and hybrids). Computed harmonic thermodynamic properties are found to be almost independent of the adopted functional, whereas quasi-harmonic structural properties are more affected by the choice of the functional, with differences that increase as the system becomes softer.

  2. Heat Distribution Systems | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Heat & Cool Home Heating Systems Heat Distribution Systems Heat Distribution Systems Radiators are used in steam and hot water heating. | Photo courtesy of iStockphoto...

  3. Waste Heat Management Options: Industrial Process Heating Systems

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Heat Management Options Industrial Process Heating Systems By Dr. Arvind C. Thekdi E-mail: athekdi@e3minc.com E3M, Inc. August 20, 2009 2 Source of Waste Heat in Industries * Steam Generation * Fluid Heating * Calcining * Drying * Heat Treating * Metal Heating * Metal and Non-metal Melting * Smelting, agglomeration etc. * Curing and Forming * Other Heating Waste heat is everywhere! Arvind Thekdi, E3M Inc Arvind Thekdi, E3M Inc 3 Waste Heat Sources from Process Heating Equipment * Hot gases -

  4. Water-heating dehumidifier

    DOE Patents [OSTI]

    Tomlinson, John J.

    2006-04-18

    A water-heating dehumidifier includes a refrigerant loop including a compressor, at least one condenser, an expansion device and an evaporator including an evaporator fan. The condenser includes a water inlet and a water outlet for flowing water therethrough or proximate thereto, or is affixed to the tank or immersed into the tank to effect water heating without flowing water. The immersed condenser design includes a self-insulated capillary tube expansion device for simplicity and high efficiency. In a water heating mode air is drawn by the evaporator fan across the evaporator to produce cooled and dehumidified air and heat taken from the air is absorbed by the refrigerant at the evaporator and is pumped to the condenser, where water is heated. When the tank of water heater is full of hot water or a humidistat set point is reached, the water-heating dehumidifier can switch to run as a dehumidifier.

  5. Fluidized bed heat treating system

    SciTech Connect (OSTI)

    Ripley, Edward B; Pfennigwerth, Glenn L

    2014-05-06

    Systems for heat treating materials are presented. The systems typically involve a fluidized bed that contains granulated heat treating material. In some embodiments a fluid, such as an inert gas, is flowed through the granulated heat treating medium, which homogenizes the temperature of the heat treating medium. In some embodiments the fluid may be heated in a heating vessel and flowed into the process chamber where the fluid is then flowed through the granulated heat treating medium. In some embodiments the heat treating material may be liquid or granulated heat treating material and the heat treating material may be circulated through a heating vessel into a process chamber where the heat treating material contacts the material to be heat treated. Microwave energy may be used to provide the source of heat for heat treating systems.

  6. Heat storage duration

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1981-01-01

    Both the amount and duration of heat storage in massive elements of a passive building are investigated. Data taken for one full winter in the Balcomb solar home are analyzed with the aid of sub-system simulation models. Heat storage duration is tallied into one-day intervals. Heat storage location is discussed and related to overall energy flows. The results are interpreted and conclusions drawn.

  7. Hydride heat pump

    DOE Patents [OSTI]

    Cottingham, James G.

    1977-01-01

    Method and apparatus for the use of hydrides to exhaust heat from one temperature source and deliver the thermal energy extracted for use at a higher temperature, thereby acting as a heat pump. For this purpose there are employed a pair of hydridable metal compounds having different characteristics working together in a closed pressure system employing a high temperature source to upgrade the heat supplied from a low temperature source.

  8. Wood and Pellet Heating

    Broader source: Energy.gov [DOE]

    Looking for an efficient, renewable way to heat your home? Wood or pellets are renewable fuel sources, and modern wood and pellet stoves are efficient heaters.

  9. Passive solar space heating

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1980-01-01

    An overview of passive solar space heating is presented indicating trends in design, new developments, performance measures, analytical design aids, and monitored building results.

  10. Heat and mass exchanger

    DOE Patents [OSTI]

    Lowenstein, Andrew; Sibilia, Marc J.; Miller, Jeffrey A.; Tonon, Thomas

    2007-09-18

    A mass and heat exchanger includes at least one first substrate with a surface for supporting a continuous flow of a liquid thereon that either absorbs, desorbs, evaporates or condenses one or more gaseous species from or to a surrounding gas; and at least one second substrate operatively associated with the first substrate. The second substrate includes a surface for supporting the continuous flow of the liquid thereon and is adapted to carry a heat exchange fluid therethrough, wherein heat transfer occurs between the liquid and the heat exchange fluid.

  11. Heat and mass exchanger

    DOE Patents [OSTI]

    Lowenstein, Andrew; Sibilia, Marc J.; Miller, Jeffrey A.; Tonon, Thomas

    2011-06-28

    A mass and heat exchanger includes at least one first substrate with a surface for supporting a continuous flow of a liquid thereon that either absorbs, desorbs, evaporates or condenses one or more gaseous species from or to a surrounding gas; and at least one second substrate operatively associated with the first substrate. The second substrate includes a surface for supporting the continuous flow of the liquid thereon and is adapted to carry a heat exchange fluid therethrough, wherein heat transfer occurs between the liquid and the heat exchange fluid.

  12. Total Space Heat-

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    12 1 18 (*) 2 1 Q 6 Buildings without Cooling ... 30 1 (*) 4 (*) 14 (*) 4 (*) 1 6 Water-Heating Energy Source Electricity ... 402 21 57 42...

  13. HEATS: Thermal Energy Storage

    SciTech Connect (OSTI)

    2012-01-01

    HEATS Project: The 15 projects that make up ARPA-Es HEATS program, short for High Energy Advanced Thermal Storage, seek to develop revolutionary, cost-effective ways to store thermal energy. HEATS focuses on 3 specific areas: 1) developing high-temperature solar thermal energy storage capable of cost-effectively delivering electricity around the clock and thermal energy storage for nuclear power plants capable of cost-effectively meeting peak demand, 2) creating synthetic fuel efficiently from sunlight by converting sunlight into heat, and 3) using thermal energy storage to improve the driving range of electric vehicles (EVs) and also enable thermal management of internal combustion engine vehicles.

  14. New Mexico Heat Flow

    SciTech Connect (OSTI)

    Shari Kelley

    2015-10-21

    This is an updated and simplified version of the New Mexico heat flow data already on the NGDS that was used for Play Fairway analysis.

  15. Heat rejection system

    DOE Patents [OSTI]

    Smith, Gregory C.; Tokarz, Richard D.; Parry, Jr., Harvey L.; Braun, Daniel J.

    1980-01-01

    A cooling system for rejecting waste heat consists of a cooling tower incorporating a plurality of coolant tubes provided with cooling fins and each having a plurality of cooling channels therein, means for directing a heat exchange fluid from the power plant through less than the total number of cooling channels to cool the heat exchange fluid under normal ambient temperature conditions, means for directing water through the remaining cooling channels whenever the ambient temperature rises above the temperature at which dry cooling of the heat exchange fluid is sufficient and means for cooling the water.

  16. Ductless Heat Pumps

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    & Events Expand News & Events Skip navigation links Residential Residential Lighting Energy Star Appliances Consumer Electronics Heat Pump Water Heaters Electric Storage Water...

  17. Heat Pump Water Heaters

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    & Events Expand News & Events Skip navigation links Residential Residential Lighting Energy Star Appliances Consumer Electronics Heat Pump Water Heaters Electric Storage Water...

  18. Geothermal Heat Pumps | Department of Energy

    Energy Savers [EERE]

    Heat Pump Systems Geothermal Heat Pumps Geothermal Heat Pumps Watch how geothermal heat ... As with any heat pump, geothermal and water-source heat pumps are able to heat, cool, and, ...

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

    SciTech Connect (OSTI)

    Mittereder, N.; Poerschke, A.

    2013-11-01

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

  20. Method and apparatus for obtaining enhanced production rate of thermal chemical reactions

    DOE Patents [OSTI]

    Tonkovich, Anna Lee Y.; Wang, Yong; Wegeng, Robert S.; Gao, Yufei

    2003-09-09

    Reactors and processes are disclosed that can utilize high heat fluxes to obtain fast, steady-state reaction rates. Porous catalysts used in conjunction with microchannel reactors to obtain high rates of heat transfer are also disclosed. Reactors and processes that utilize short contact times, high heat flux and low pressure drop are described. Improved methods of steam reforming are also provided.

  1. Method and apparatus for obtaining enhanced production rate of thermal chemical reactions

    DOE Patents [OSTI]

    Tonkovich, Anna Lee Y.; Wang, Yong; Wegeng, Robert S.; Gao, Yufei

    2006-05-16

    Reactors and processes are disclosed that can utilize high heat fluxes to obtain fast, steady-state reaction rates. Porous catalysts used in conjunction with microchannel reactors to obtain high rates of heat transfer are also disclosed. Reactors and processes that utilize short contact times, high heat flux and low pressure drop are described. Improved methods of steam reforming are also provided.

  2. Radiative heat transfer in 2D Dirac materials

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Rodriguez-López, Pablo; Tse, Wang -Kong; Dalvit, Diego A. R.

    2015-05-12

    We compute the radiative heat transfer between two sheets of 2D Dirac materials, including topological Chern insulators and graphene, within the framework of the local approximation for the optical response of these materials. In this approximation, which neglects spatial dispersion, we derive both numerically and analytically the short-distance asymptotic of the near-field heat transfer in these systems, and show that it scales as the inverse of the distance between the two sheets. In conclusion, we discuss the limitations to the validity of this scaling law imposed by spatial dispersion in 2D Dirac materials.

  3. Multimegawatt gyrotrons for plasma heating

    SciTech Connect (OSTI)

    Advani, R.; Denison, D.; Kreischer, K.E.; Shapiro, M.A.; Temkin, R.J.

    1999-07-01

    The gyrotron is under development as a high power source for plasma heating at electron cyclotron resonance. For heating large scale plasmas, such as the DIII-D machine at General Atomics, it is advantageous to have high unit power heating sources to reduce the cost and complexity of the system. The authors will present preliminary designs of 1.5 and 2 MW gyrotrons at a frequency of 110 GHz. The gyrotron designs are based on previous successful results at the 1 MW level at frequencies from 110 to 170 GHz. The baseline design is for a TE{sub 28.8} mode cavity with an electron beam of 80 to 110 kV and a current of up to 80A. The expected efficiency exceeds 30% but it should increase to over 50% with a depressed collector. The output beam will be a Gaussian TEM{sub 00} mode in free space. The gyrotron will be investigated experimentally in short pulse operation (approximately 3 microseconds) at MIT and, if successful, will be developed in a 10s pulsed or CW version by industry. There are two competing approaches for the design of multimegawatt gyrotrons: conventional, cylindrical cavity gyrotrons and coaxial cavity gyrotrons. The conventional cavity approach is being considered as an extension of present day gyrotron research at 110 GHz. The coaxial cavity gyrotron is under investigation at MIT with the goal of output powers of 3 MW at 140 GHz. Recent experimental results from the coaxial cavity gyrotron at power levels in excess of 1 MW will be presented.

  4. Compressor Selection and Equipment Sizing for Cold Climate Heat Pumps

    SciTech Connect (OSTI)

    Shen, Bo; Abdelaziz, Omar; Rice, C Keith

    2014-01-01

    In order to limit heating capacity degradation at -25 C (-13 F) ambient to 25%, compared to the nominal rating point capacity at 8.3 C (47 F), an extensive array of design and sizing options were investigated, based on fundamental equipment system modeling and building energy simulation. Sixteen equipment design options were evaluated in one commercial building and one residential building, respectively in seven cities. The energy simulation results were compared to three baseline cases: 100% electric resistance heating, a 9.6 HSPF single-speed heat pump unit, and 90% AFUE gas heating system. The general recommendation is that variable-speed compressors and tandem compressors, sized such that their rated heating capacity at a low speed matching the building design cooling load, are able to achieve the capacity goal at low ambient temperatures by over-speeding, for example, a home with a 3.0 ton design cooling load, a tandem heat pump could meet this cooling load running a single compressor, while running both compressors to meet heating load at low ambient temperatures in a cold climate. Energy savings and electric resistance heat reductions vary with building types, energy codes and climate zones. Oversizing a heat pump can result in larger energy saving in a less energy efficient building and colder regions due to reducing electric resistance heating. However, in a more energy-efficient building or for buildings in warmer climates, one has to consider balance between reduction of resistance heat and addition of cyclic loss.

  5. Indirect evaporative coolers with enhanced heat transfer

    DOE Patents [OSTI]

    Kozubal, Eric; Woods, Jason; Judkoff, Ron

    2015-09-22

    A separator plate assembly for use in an indirect evaporative cooler (IEC) with an air-to-air heat exchanger. The assembly includes a separator plate with a first surface defining a dry channel and a second surface defining a wet channel. The assembly includes heat transfer enhancements provided on the first surface for increasing heat transfer rates. The heat transfer enhancements may include slit fins with bodies extending outward from the first surface of separator plate or may take other forms including vortex generators, offset strip fins, and wavy fins. In slit fin implementations, the separator plate has holes proximate to each of the slit fins, and the separator plate assembly may include a sealing layer applied to the second surface of the separator plate to block air flow through the holes. The sealing layer can be a thickness of adhesive, and a layer of wicking material is applied to the adhesive.

  6. Rate Case Elements

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Proceeding Rate Information Residential Exchange Program Surplus Power Sales Reports Rate Case Elements BPA's rate cases are decided "on the record." That is, in making a decision...

  7. Heat-Pipe Wick Characterization

    SciTech Connect (OSTI)

    JONES II,JERRY LEE

    2000-08-15

    The development of liquid metal heat-pipes for use in solar powered Stirling engines has led to an in-depth analysis of heat-pipe wick properties. To model the flow of liquid sodium through the wick its two-phase permeability measurement is of interest. The permeability will be measured by constructing a test cell made up of a wick sample sintered to a manifold. Measuring the volumetric flow rate through the wick will allow for a determination of the wick's permeability as a function of pressure. Currently, simple estimates of permeability as a function of vapor fraction of a porous media are being used as a model to calculate the two-phase permeability. The above mentioned experiment will be used to test the existing formulas validity. The plan is to make use of a known procedure for testing permeability and apply those techniques to a felt-metal wick. The results will be used to verify and/or modify the two-phase permeability estimates. With the increasing desire to replace directly illuminated engines with the much more efficient heat-pipe apparatus it is inherently clear that the usefulness of known wick properties will make wick permeability design a simpler process.

  8. Microchannel heat sink assembly

    DOE Patents [OSTI]

    Bonde, W.L.; Contolini, R.J.

    1992-03-24

    The present invention provides a microchannel heat sink with a thermal range from cryogenic temperatures to several hundred degrees centigrade. The heat sink can be used with a variety of fluids, such as cryogenic or corrosive fluids, and can be operated at a high pressure. The heat sink comprises a microchannel layer preferably formed of silicon, and a manifold layer preferably formed of glass. The manifold layer comprises an inlet groove and outlet groove which define an inlet manifold and an outlet manifold. The inlet manifold delivers coolant to the inlet section of the microchannels, and the outlet manifold receives coolant from the outlet section of the microchannels. In one embodiment, the manifold layer comprises an inlet hole extending through the manifold layer to the inlet manifold, and an outlet hole extending through the manifold layer to the outlet manifold. Coolant is supplied to the heat sink through a conduit assembly connected to the heat sink. A resilient seal, such as a gasket or an O-ring, is disposed between the conduit and the hole in the heat sink in order to provide a watertight seal. In other embodiments, the conduit assembly may comprise a metal tube which is connected to the heat sink by a soft solder. In still other embodiments, the heat sink may comprise inlet and outlet nipples. The present invention has application in supercomputers, integrated circuits and other electronic devices, and is suitable for cooling materials to superconducting temperatures. 13 figs.

  9. Combined Heat and Power

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Combined Heat and Power 1 Technology Assessment 2 Contents 3 1. Introduction to the Technology/System ............................................................................................... 2 4 1.1 Combined Heat and Power overview ........................................................................................... 2 5 1.2 Benefits of CHP for the Nation ...................................................................................................... 4 6 1.3 Benefits of CHP for

  10. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard

    1984-01-01

    A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure, as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate intallation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer.

  11. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard

    1984-01-01

    A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure, as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to faciliate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer.

  12. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard

    1984-01-01

    A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure, as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer.

  13. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard

    1981-01-01

    A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure, as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer.

  14. Radioisotopic heat source

    DOE Patents [OSTI]

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

    1975-09-30

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

  15. Microchannel heat sink assembly

    DOE Patents [OSTI]

    Bonde, Wayne L.; Contolini, Robert J.

    1992-01-01

    The present invention provides a microchannel heat sink with a thermal range from cryogenic temperatures to several hundred degrees centigrade. The heat sink can be used with a variety of fluids, such as cryogenic or corrosive fluids, and can be operated at a high pressure. The heat sink comprises a microchannel layer preferably formed of silicon, and a manifold layer preferably formed of glass. The manifold layer comprises an inlet groove and outlet groove which define an inlet manifold and an outlet manifold. The inlet manifold delivers coolant to the inlet section of the microchannels, and the outlet manifold receives coolant from the outlet section of the microchannels. In one embodiment, the manifold layer comprises an inlet hole extending through the manifold layer to the inlet manifold, and an outlet hole extending through the manifold layer to the outlet manifold. Coolant is supplied to the heat sink through a conduit assembly connected to the heat sink. A resilient seal, such as a gasket or an O-ring, is disposed between the conduit and the hole in the heat sink in order to provide a watetight seal. In other embodiments, the conduit assembly may comprise a metal tube which is connected to the heat sink by a soft solder. In still other embodiments, the heat sink may comprise inlet and outlet nipples. The present invention has application in supercomputers, integrated circuits and other electronic devices, and is suitable for cooling materials to superconducting temperatures.

  16. Geothermal Heat Pumps - Heating Mode | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Heating Mode Geothermal Heat Pumps - Heating Mode In winter, fluid passing through this vertical, closed loop system is warmed by the heat of the earth; this heat is then transferred to the building. Heating Mode Animated Slide (PowerPoint 493 KB) Note: To view this animation in PowerPoint use 'Slide Show' mode. Simple illustration showing the transfer of heat from the ground to a building space to provide space heating. Simple illustration showing the transfer of heat from the ground to a

  17. Program listing for heat-pump seasonal-performance model (SPM). [CNHSPM

    SciTech Connect (OSTI)

    Not Available

    1982-06-30

    The computer program CNHSPM is listed which predicts heat pump seasonal energy consumption (including defrost, cyclic degradation, and supplementary heat) using steady state rating point performance and binned weather data. (LEW)

  18. Solar heating panel arrangement

    SciTech Connect (OSTI)

    Chang, M.K.

    1983-07-12

    A solar heating panel arrangement and method are disclosed wherein a plurality of spherical lenses transmit and focus solar radiation onto the upper surface of a fluid passage for various relative positions of the sun. The upper surface of the passage is in heat transfer proximity to the fluid therein, causing solar radiation focused thereon to be transferred to the fluid in the form of heat. Solar radiation not directly incident on the lenses may be reflected onto them to increase the amount of solar energy available for transfer to the fluid. A supplementary insulating flow of fluid may also be provided above the passage to absorb heat passing upwardly therefrom and retain the heat within the system.

  19. Improved solar heating systems

    DOE Patents [OSTI]

    Schreyer, J.M.; Dorsey, G.F.

    1980-05-16

    An improved solar heating system is described in which the incident radiation of the sun is absorbed on collector panels, transferred to a storage unit and then distributed as heat for a building and the like. The improvement is obtained by utilizing a storage unit comprising separate compartments containing an array of materials having different melting points ranging from 75 to 180/sup 0/F. The materials in the storage system are melted in accordance with the amount of heat absorbed from the sun and then transferred to the storage system. An efficient low volume storage system is provided by utilizing the latent heat of fusion of the materials as they change states in storing ad releasing heat for distribution.

  20. Solar heating system

    DOE Patents [OSTI]

    Schreyer, James M.; Dorsey, George F.

    1982-01-01

    An improved solar heating system in which the incident radiation of the sun is absorbed on collector panels, transferred to a storage unit and then distributed as heat for a building and the like. The improvement is obtained by utilizing a storage unit comprising separate compartments containing an array of materials having different melting points ranging from 75.degree. to 180.degree. F. The materials in the storage system are melted in accordance with the amount of heat absorbed from the sun and then transferred to the storage system. An efficient low volume storage system is provided by utilizing the latent heat of fusion of the materials as they change states in storing and releasing heat for distribution.

  1. Knudsen heat capacity

    SciTech Connect (OSTI)

    Babac, Gulru; Reese, Jason M.

    2014-05-15

    We present a Knudsen heat capacity as a more appropriate and useful fluid property in micro/nanoscale gas systems than the constant pressure heat capacity. At these scales, different fluid processes come to the fore that are not normally observed at the macroscale. For thermodynamic analyses that include these Knudsen processes, using the Knudsen heat capacity can be more effective and physical. We calculate this heat capacity theoretically for non-ideal monatomic and diatomic gases, in particular, helium, nitrogen, and hydrogen. The quantum modification for para and ortho hydrogen is also considered. We numerically model the Knudsen heat capacity using molecular dynamics simulations for the considered gases, and compare these results with the theoretical ones.

  2. Heat pipes and use of heat pipes in furnace exhaust

    DOE Patents [OSTI]

    Polcyn, Adam D.

    2010-12-28

    An array of a plurality of heat pipe are mounted in spaced relationship to one another with the hot end of the heat pipes in a heated environment, e.g. the exhaust flue of a furnace, and the cold end outside the furnace. Heat conversion equipment is connected to the cold end of the heat pipes.

  3. Shock heating of the solar wind plasma

    SciTech Connect (OSTI)

    Whang, Y.C.; Liu, Shaoliang ); Burlaga, L.F. )

    1990-11-01

    The authors present a study of all shocks observed from Pioneers and Voyagers in 1973-1982. The average shock strength increases with the heliocentric distance outside 1 AU, reaches a maximum near 5 AU, and then decreases with the distance. The increase in the entropy of the solar wind protons across shocks also reaches a maximum near 5 AU. When an average shock propagates through the solar wind, the shock heating increases the entropy of the solar wind protons by approximately 0.8 {times} 10{sup {minus}23} J/K/proton. They also use plasma data from Voyagers and Pioneers between 1 and 30 AU and data from IMP at 1 AU to calculate the increase in the average entropy of solar wind protons with the heliocentric distance. When the distance increases by a factor of 10, the entropy increases by about 4 {times} 10{sup {minus}23} J/K/proton. In order to evaluate the role played by shocks for the heating of the solar wind, they use a MHD simulation model to calculate the entropy changes for the November, 1977 event. Shock heating is the only heating mechanism included in the model. The calculated entropy increase agrees reasonably well with that calculated from observational data. The simulation result suggests that shocks are chiefly responsible for the heating of the solar wind plasma between 1 and 15 AU.

  4. Data approximation using a blending type spline construction

    SciTech Connect (OSTI)

    Dalmo, Rune; Bratlie, Jostein

    2014-11-18

    Generalized expo-rational B-splines (GERBS) is a blending type spline construction where local functions at each knot are blended together by C{sup k}-smooth basis functions. One way of approximating discrete regular data using GERBS is by partitioning the data set into subsets and fit a local function to each subset. Partitioning and fitting strategies can be devised such that important or interesting data points are interpolated in order to preserve certain features. We present a method for fitting discrete data using a tensor product GERBS construction. The method is based on detection of feature points using differential geometry. Derivatives, which are necessary for feature point detection and used to construct local surface patches, are approximated from the discrete data using finite differences.

  5. Doorway states in the random-phase approximation

    SciTech Connect (OSTI)

    De Pace, A.; Molinari, A.; Weidenmüller, H.A.

    2014-12-15

    By coupling a doorway state to a sea of random background states, we develop the theory of doorway states in the framework of the random-phase approximation (RPA). Because of the symmetry of the RPA equations, that theory is radically different from the standard description of doorway states in the shell model. We derive the Pastur equation in the limit of large matrix dimension and show that the results agree with those of matrix diagonalization in large spaces. The complexity of the Pastur equation does not allow for an analytical approach that would approximately describe the doorway state. Our numerical results display unexpected features: The coupling of the doorway state with states of opposite energy leads to strong mutual attraction.

  6. Process for heating coal-oil slurries

    DOE Patents [OSTI]

    Braunlin, W.A.; Gorski, A.; Jaehnig, L.J.; Moskal, C.J.; Naylor, J.D.; Parimi, K.; Ward, J.V.

    1984-01-03

    Controlling gas to slurry volume ratio to achieve a gas holdup of about 0.4 when heating a flowing coal-oil slurry and a hydrogen containing gas stream allows operation with virtually any coal to solvent ratio and permits operation with efficient heat transfer and satisfactory pressure drops. The critical minimum gas flow rate for any given coal-oil slurry will depend on numerous factors such as coal concentration, coal particle size distribution, composition of the solvent (including recycle slurries), and type of coal. Further system efficiency can be achieved by operating with multiple heating zones to provide a high heat flux when the apparent viscosity of the gas saturated slurry is highest. Operation with gas flow rates below the critical minimum results in system instability indicated by temperature excursions in the fluid and at the tube wall, by a rapid increase and then decrease in overall pressure drop with decreasing gas flow rate, and by increased temperature differences between the temperature of the bulk fluid and the tube wall. At the temperatures and pressures used in coal liquefaction preheaters the coal-oil slurry and hydrogen containing gas stream behaves essentially as a Newtonian fluid at shear rates in excess of 150 sec[sup [minus]1]. The gas to slurry volume ratio should also be controlled to assure that the flow regime does not shift from homogeneous flow to non-homogeneous flow. Stable operations have been observed with a maximum gas holdup as high as 0.72. 29 figs.

  7. Process for heating coal-oil slurries

    DOE Patents [OSTI]

    Braunlin, Walter A.; Gorski, Alan; Jaehnig, Leo J.; Moskal, Clifford J.; Naylor, Joseph D.; Parimi, Krishnia; Ward, John V.

    1984-01-03

    Controlling gas to slurry volume ratio to achieve a gas holdup of about 0.4 when heating a flowing coal-oil slurry and a hydrogen containing gas stream allows operation with virtually any coal to solvent ratio and permits operation with efficient heat transfer and satisfactory pressure drops. The critical minimum gas flow rate for any given coal-oil slurry will depend on numerous factors such as coal concentration, coal particle size distribution, composition of the solvent (including recycle slurries), and type of coal. Further system efficiency can be achieved by operating with multiple heating zones to provide a high heat flux when the apparent viscosity of the gas saturated slurry is highest. Operation with gas flow rates below the critical minimum results in system instability indicated by temperature excursions in the fluid and at the tube wall, by a rapid increase and then decrease in overall pressure drop with decreasing gas flow rate, and by increased temperature differences between the temperature of the bulk fluid and the tube wall. At the temperatures and pressures used in coal liquefaction preheaters the coal-oil slurry and hydrogen containing gas stream behaves essentially as a Newtonian fluid at shear rates in excess of 150 sec.sup. -1. The gas to slurry volume ratio should also be controlled to assure that the flow regime does not shift from homogeneous flow to non-homogeneous flow. Stable operations have been observed with a maximum gas holdup as high as 0.72.

  8. The Monte Carlo Independent Column Approximation Model Intercomparison

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Project (McMIP) The Monte Carlo Independent Column Approximation Model Intercomparison Project (McMIP) Barker, Howard Meteorological Service of Canada Cole, Jason Meteorological Service of Canada Raisanen, Petri Finnish Meteorological Institute Pincus, Robert NOAA-CIRES Climate Diagnostics Center Morcrette, Jean-Jacques European Centre for Medium-Range Weather Forecasts Li, Jiangnan Canadian Center for Climate Modelling Stephens, Graeme Colorado State University Vaillancourt, Paul

  9. Crossing contours in the interacting boson approximation (IBA) symmetry triangle

    SciTech Connect (OSTI)

    McCutchan, E. A.; Casten, R. F.

    2006-11-15

    Constant contours of basic observables are discussed in the context of the interacting boson approximation (IBA) symmetry triangle. Contours that exhibit orthogonal crossing within the triangle are presented as a method for determining a set of parameter values for a particular nucleus and trajectories for isotopic chains. A set of contours that highlights a class of nuclei that are outside the two-parameter IBA-1 Hamitonian space is also presented.

  10. COMPLEXITY & APPROXIMABILITY OF QUANTIFIED & STOCHASTIC CONSTRAINT SATISFACTION PROBLEMS

    SciTech Connect (OSTI)

    H. B. HUNT; M. V. MARATHE; R. E. STEARNS

    2001-06-01

    Let D be an arbitrary (not necessarily finite) nonempty set, let C be a finite set of constant symbols denoting arbitrary elements of D, and let S and T be an arbitrary finite set of finite-arity relations on D. We denote the problem of determining the satisfiability of finite conjunctions of relations in S applied to variables (to variables and symbols in C) by SAT(S) (by SATc(S).) Here, we study simultaneously the complexity of decision, counting, maximization and approximate maximization problems, for unquantified, quantified and stochastically quantified formulas. We present simple yet general techniques to characterize simultaneously, the complexity or efficient approximability of a number of versions/variants of the problems SAT(S), Q-SAT(S), S-SAT(S),MAX-Q-SAT(S) etc., for many different such D,C,S,T. These versions/variants include decision, counting, maximization and approximate maximization problems, for unquantified, quantified and stochastically quantified formulas. Our unified approach is based on the following two basic concepts: (i) strongly-local replacements/reductions and (ii) relational/algebraic representability. Some of the results extend the earlier results in [Pa85,LMP99,CF+93,CF+94] Our techniques and results reported here also provide significant steps towards obtaining dichotomy theorems, for a number of the problems above, including the problems MAX-Q-SAT(S), and MAX-S-SAT(S). The discovery of such dichotomy theorems, for unquantified formulas, has received significant recent attention in the literature [CF+93, CF+94, Cr95, KSW97]. Keywords: NP-hardness; Approximation Algorithms; PSPACE-hardness; Quantified and Stochastic Constraint Satisfaction Problems.

  11. Power Rate Cases (pbl/rates)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Choices (2003-06) Power Function Review (PFR) Firstgov Power Rate Cases BPA's wholesale power rates are set to recover its costs and repay the U.S. Treasury for the Federal...

  12. Chlorite Dissolution Rates

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Carroll, Susan

    Spreadsheets provides measured chlorite rate data from 100 to 300C at elevated CO2. Spreadsheet includes derived rate equation.

  13. Chlorite Dissolution Rates

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Carroll, Susan

    2013-07-01

    Spreadsheets provides measured chlorite rate data from 100 to 300C at elevated CO2. Spreadsheet includes derived rate equation.

  14. Radiant Heating | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Heating Systems » Radiant Heating Radiant Heating In-wall radiant heating in a house under construction near Denver. | Photo courtesy of Warren Gretz, NREL. In-wall radiant heating in a house under construction near Denver. | Photo courtesy of Warren Gretz, NREL. Radiant heating systems supply heat directly to the floor or to panels in the wall or ceiling of a house. The systems depend largely on radiant heat transfer -- the delivery of heat directly from the hot surface to the people and

  15. Bypass valve and coolant flow controls for optimum temperatures in waste heat recovery systems

    DOE Patents [OSTI]

    Meisner, Gregory P

    2013-10-08

    Implementing an optimized waste heat recovery system includes calculating a temperature and a rate of change in temperature of a heat exchanger of a waste heat recovery system, and predicting a temperature and a rate of change in temperature of a material flowing through a channel of the waste heat recovery system. Upon determining the rate of change in the temperature of the material is predicted to be higher than the rate of change in the temperature of the heat exchanger, the optimized waste heat recovery system calculates a valve position and timing for the channel that is configurable for achieving a rate of material flow that is determined to produce and maintain a defined threshold temperature of the heat exchanger, and actuates the valve according to the calculated valve position and calculated timing.

  16. Do-it-yourself solar heating. Final report

    SciTech Connect (OSTI)

    Stevenson, J.

    1984-01-01

    Presented is a do-it-yourself method of building a solar greenhouse for the purpose of heating a house. During the operational periods, following the construction of the greenhouse, severe problems were encountered. The heat losses at night during the heating season lowered temperatures inside the greenhouse to below freezing on some occasions. Overheating was a problem encountered during the summer months. Daily high and low temperatures are recorded for both inside and outside of the greenhouse. The payback period for the present greenhouse was calculated to be approximately 21.5 years. Recommendations for improving the greenhouse design and efficiency are included. (BCS)

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

    SciTech Connect (OSTI)

    Elbel, Dr. Stefan W.; Petersen, Michael

    2013-04-25

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

  18. Heat Transfer and Latent Heat Storage in Inorganic Molten Salts for Concentrating Solar Power Plants

    SciTech Connect (OSTI)

    Mathur, Anoop

    2013-08-14

    A key technological issue facing the success of future Concentrating Solar Thermal Power (CSP) plants is creating an economical Thermal Energy Storage (TES) system. Current TES systems use either sensible heat in fluids such as oil, or molten salts, or use thermal stratification in a dual-media consisting of a solid and a heat-transfer fluid. However, utilizing the heat of fusion in inorganic molten salt mixtures in addition to sensible heat , as in a Phase change material (PCM)-based TES, can significantly increase the energy density of storage requiring less salt and smaller containers. A major issue that is preventing the commercial use of PCM-based TES is that it is difficult to discharge the latent heat stored in the PCM melt. This is because when heat is extracted, the melt solidifies onto the heat exchanger surface decreasing the heat transfer. Even a few millimeters of thickness of solid material on heat transfer surface results in a large drop in heat transfer due to the low thermal conductivity of solid PCM. Thus, to maintain the desired heat rate, the heat exchange area must be large which increases cost. This project demonstrated that the heat transfer coefficient can be increase ten-fold by using forced convection by pumping a hyper-eutectic salt mixture over specially coated heat exchanger tubes. However,only 15% of the latent heat is used against a goal of 40% resulting in a projected cost savings of only 17% against a goal of 30%. Based on the failure mode effect analysis and experience with pumping salt at near freezing point significant care must be used during operation which can increase the operating costs. Therefore, we conclude the savings are marginal to justify using this concept for PCM-TES over a two-tank TES. The report documents the specialty coatings, the composition and morphology of hypereutectic salt mixtures and the results from the experiment conducted with the active heat exchanger along with the lessons learnt during

  19. Heat Exchangers for Solar Water Heating Systems | Department...

    Broader source: Energy.gov (indexed) [DOE]

    from iStockphoto.com Image of a heat exchanger. | Photo from iStockphoto.com Solar water heating systems use heat exchangers to transfer solar energy absorbed in solar...

  20. Integrating preconcentrator heat controller

    DOE Patents [OSTI]

    Bouchier, Francis A.; Arakaki, Lester H.; Varley, Eric S.

    2007-10-16

    A method and apparatus for controlling the electric resistance heating of a metallic chemical preconcentrator screen, for example, used in portable trace explosives detectors. The length of the heating time-period is automatically adjusted to compensate for any changes in the voltage driving the heating current across the screen, for example, due to gradual discharge or aging of a battery. The total deposited energy in the screen is proportional to the integral over time of the square of the voltage drop across the screen. Since the net temperature rise, .DELTA.T.sub.s, of the screen, from beginning to end of the heating pulse, is proportional to the total amount of heat energy deposited in the screen during the heating pulse, then this integral can be calculated in real-time and used to terminate the heating current when a pre-set target value has been reached; thereby providing a consistent and reliable screen temperature rise, .DELTA.T.sub.s, from pulse-to-pulse.

  1. Micro heat barrier

    DOE Patents [OSTI]

    Marshall, Albert C.; Kravitz, Stanley H.; Tigges, Chris P.; Vawter, Gregory A.

    2003-08-12

    A highly effective, micron-scale micro heat barrier structure and process for manufacturing a micro heat barrier based on semiconductor and/or MEMS fabrication techniques. The micro heat barrier has an array of non-metallic, freestanding microsupports with a height less than 100 microns, attached to a substrate. An infrared reflective membrane (e.g., 1 micron gold) can be supported by the array of microsupports to provide radiation shielding. The micro heat barrier can be evacuated to eliminate gas phase heat conduction and convection. Semi-isotropic, reactive ion plasma etching can be used to create a microspike having a cusp-like shape with a sharp, pointed tip (<0.1 micron), to minimize the tip's contact area. A heat source can be placed directly on the microspikes. The micro heat barrier can have an apparent thermal conductivity in the range of 10.sup.-6 to 10.sup.-7 W/m-K. Multiple layers of reflective membranes can be used to increase thermal resistance.

  2. Efficiency and large deviations in time-asymmetric stochastic heat engines

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gingrich, Todd R.; Rotskoff, Grant M.; Vaikuntanathan, Suriyanarayanan; Geissler, Phillip L.

    2014-10-24

    In a stochastic heat engine driven by a cyclic non-equilibrium protocol, fluctuations in work and heat give rise to a fluctuating efficiency. Using computer simulations and tools from large deviation theory, we have examined these fluctuations in detail for a model two-state engine. We find in general that the form of efficiency probability distributions is similar to those described by Verley et al (2014 Nat. Commun. 5 4721), in particular featuring a local minimum in the long-time limit. In contrast to the time-symmetric engine protocols studied previously, however, this minimum need not occur at the value characteristic of a reversible Carnot engine. Furthermore, while the local minimum may reside at the global minimum of a large deviation rate function, it does not generally correspond to the least likely efficiency measured over finite time. Lastly, we introduce a general approximation for the finite-time efficiency distribution,more » $$P(\\eta )$$, based on large deviation statistics of work and heat, that remains very accurate even when $$P(\\eta )$$ deviates significantly from its large deviation form.« less

  3. Approximate models for the study of exponential changed quantities: Application on the plasma waves growth rate or damping

    SciTech Connect (OSTI)

    Xaplanteris, C. L.; Xaplanteris, L. C.; Leousis, D. P.

    2014-03-15

    Many physical phenomena that concern the research these days are basically complicated because of being multi-parametric. Thus, their study and understanding meets with big if not unsolved obstacles. Such complicated and multi-parametric is the plasmatic state as well, where the plasma and the physical quantities that appear along with it have chaotic behavior. Many of those physical quantities change exponentially and at most times they are stabilized by presenting wavy behavior. Mostly in the transitive state rather than the steady state, the exponentially changing quantities (Growth, Damping etc) depend on each other in most cases. Thus, it is difficult to distinguish the cause from the result. The present paper attempts to help this difficult study and understanding by proposing mathematical exponential models that could relate with the study and understanding of the plasmatic wavy instability behavior. Such instabilities are already detected, understood and presented in previous publications of our laboratory. In other words, our new contribution is the study of the already known plasmatic quantities by using mathematical models (modeling and simulation). These methods are both useful and applicable in the chaotic theory. In addition, our ambition is to also conduct a list of models useful for the study of chaotic problems, such as those that appear into the plasma, starting with this paper's examples.

  4. Heat treatment furnace

    DOE Patents [OSTI]

    Seals, Roland D; Parrott, Jeffrey G; DeMint, Paul D; Finney, Kevin R; Blue, Charles T

    2014-10-21

    A furnace heats through both infrared radiation and convective air utilizing an infrared/purge gas design that enables improved temperature control to enable more uniform treatment of workpieces. The furnace utilizes lamps, the electrical end connections of which are located in an enclosure outside the furnace chamber, with the lamps extending into the furnace chamber through openings in the wall of the chamber. The enclosure is purged with gas, which gas flows from the enclosure into the furnace chamber via the openings in the wall of the chamber so that the gas flows above and around the lamps and is heated to form a convective mechanism in heating parts.

  5. Stirling engine heating system

    SciTech Connect (OSTI)

    Johansson, L.N.; Houtman, W.H.; Percival, W.H.

    1988-06-28

    A hot gas engine is described wherein a working gas flows back and forth in a closed path between a relatively cooler compression cylinder side of the engine and a relatively hotter expansion cylinder side of the engine and the path contains means including a heat source and a heat sink acting upon the gas in cooperation with the compression and expansion cylinders to cause the gas to execute a thermodynamic cycle wherein useful mechanical output power is developed by the engine, the improvement in the heat source which comprises a plurality of individual tubes each forming a portion of the closed path for the working gas.

  6. Condensing Heating and Water Heating Equipment Workshop Location...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Condensing Heating and Water Heating Equipment Workshop Location: Washington Gas Light Appliance Training Facility 6801 Industrial Road Springfield, VA Date: October 9, 2014 Time: ...

  7. Capture of Heat Energy from Diesel Engine Exhaust

    SciTech Connect (OSTI)

    Chuen-Sen Lin

    2008-12-31

    Diesel generators produce waste heat as well as electrical power. About one-third of the fuel energy is released from the exhaust manifolds of the diesel engines and normally is not captured for useful applications. This project studied different waste heat applications that may effectively use the heat released from exhaust of Alaskan village diesel generators, selected the most desirable application, designed and fabricated a prototype for performance measurements, and evaluated the feasibility and economic impact of the selected application. Exhaust flow rate, composition, and temperature may affect the heat recovery system design and the amount of heat that is recoverable. In comparison with the other two parameters, the effect of exhaust composition may be less important due to the large air/fuel ratio for diesel engines. This project also compared heat content and qualities (i.e., temperatures) of exhaust for three types of fuel: conventional diesel, a synthetic diesel, and conventional diesel with a small amount of hydrogen. Another task of this project was the development of a computer-aided design tool for the economic analysis of selected exhaust heat recovery applications to any Alaskan village diesel generator set. The exhaust heat recovery application selected from this study was for heating. An exhaust heat recovery system was fabricated, and 350 hours of testing was conducted. Based on testing data, the exhaust heat recovery heating system showed insignificant effects on engine performance and maintenance requirements. From measurements, it was determined that the amount of heat recovered from the system was about 50% of the heat energy contained in the exhaust (heat contained in exhaust was evaluated based on environment temperature). The estimated payback time for 100% use of recovered heat would be less than 3 years at a fuel price of $3.50 per gallon, an interest rate of 10%, and an engine operation of 8 hours per day. Based on experimental data

  8. Union Power Cooperative- Residential Energy Efficient Heat Pump Loan Program

    Office of Energy Efficiency and Renewable Energy (EERE)

    Union Power Cooperative offers low interest loans to help its qualifying residential customers finance new, energy-efficient heat pumps. Interest rates, currently at 9%, will be fixed for the term...

  9. Oscillating side-branch enhancements of thermoacoustic heat exchangers

    DOE Patents [OSTI]

    Swift, Gregory W.

    2003-05-13

    A regenerator-based engine or refrigerator has a regenerator with two ends at two different temperatures, through which a gas oscillates at a first oscillating volumetric flow rate in the direction between the two ends and in which the pressure of the gas oscillates, and first and second heat exchangers, each of which is at one of the two different temperatures. A dead-end side branch into which the gas oscillates has compliance and is connected adjacent to one of the ends of the regenerator to form a second oscillating gas flow rate additive with the first oscillating volumetric flow rate, the compliance having a volume effective to provide a selected total oscillating gas volumetric flow rate through the first heat exchanger. This configuration enables the first heat exchanger to be configured and located to better enhance the performance of the heat exchanger rather than being confined to the location and configuration of the regenerator.

  10. Reduce Radiation Losses from Heating Equipment; Industrial Technologie...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    line of sight, and the rate of heat transfer increases with the fourth power of the ... These graphs give results that are within 5% of the results of using detailed view- factor ...

  11. Haywood EMC- Residential Heat Pump and Weatherization Loan Program

    Broader source: Energy.gov [DOE]

    Haywood EMC offers a low interest loan to residential customers to finance the purchase of an energy efficient heat pump and certain weatherization measures. The current interest rate is 5% and the...

  12. Building America January 2015 Webinar: Multifamily Central Heat...

    Energy Savers [EERE]

    sensor placement - Non-optimal setpoints * 140F heat ... of power and capacity to outdoor dry bulb and entering water temperature. Monitored data: Avg. inlet 125.4 F, Flow rate ...

  13. Rechargeable Heat Battery's Secret Revealed

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Rechargeable Heat Battery Rechargeable Heat Battery's Secret Revealed Solar energy capture ... Contact: John Hules, JAHules@lbl.gov, +1 510 486 6008 2011-01-11-Heat-Battery.jpg A ...

  14. Water Heating | Department of Energy

    Energy Savers [EERE]

    Water Heating Water Heating September 2, 2015 - 11:07am Addthis Low-flow fixtures will help you reduce your hot water use and save money on your water heating bills. | Photo...

  15. Energy 101: Geothermal Heat Pumps

    Broader source: Energy.gov [DOE]

    An energy-efficient heating and cooling alternative, the geothermal heat pump system moves heat from the ground to a building (or from a building to the ground) through a series of flexible pipe ...

  16. Radiant Heating | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Radiant heating systems supply heat directly to the floor or to ... of heat directly from the hot surface to the people and ... wood-fired boilers, solar water heaters, or a combination ...

  17. Exploring the Random Phase Approximately for materials chemistry and physics

    SciTech Connect (OSTI)

    Ruzsinsky, Adrienn

    2015-03-23

    This proposal focuses on improved accuracy for the delicate energy differences of interest in materials chemistry with the fully nonlocal random phase approximation (RPA) in a density functional context. Could RPA or RPA-like approaches become standard methods of first-principles electronic-structure calculation for atoms, molecules, solids, surfaces, and nano-structures? Direct RPA includes the full exact exchange energy and a nonlocal correlation energy from the occupied and unoccupied Kohn-Sham orbitals and orbital energies, with an approximate but universal description of long-range van der Waals attraction. RPA also improves upon simple pair-wise interaction potentials or vdW density functional theory. This improvement is essential to capture accurate energy differences in metals and different phases of semiconductors. The applications in this proposal are challenges for the simpler approximations of Kohn-Sham density functional theory, which are part of the current “standard model” for quantum chemistry and condensed matter physics. Within this project we already applied RPA on different structural phase transitions on semiconductors, metals and molecules. Although RPA predicts accurate structural parameters, RPA has proven not equally accurate in all kinds of structural phase transitions. Therefore a correction to RPA can be necessary in many cases. We are currently implementing and testing a nonempirical, spatially nonlocal, frequency-dependent model for the exchange-correlation kernel in the adiabatic-connection fluctuation-dissipation context. This kernel predicts a nearly-exact correlation energy for the electron gas of uniform density. If RPA or RPA-like approaches prove to be reliably accurate, then expected increases in computer power may make them standard in the electronic-structure calculations of the future.

  18. COMPLEXITY&APPROXIMABILITY OF QUANTIFIED&STOCHASTIC CONSTRAINT SATISFACTION PROBLEMS

    SciTech Connect (OSTI)

    Hunt, H. B.; Marathe, M. V.; Stearns, R. E.

    2001-01-01

    Let D be an arbitrary (not necessarily finite) nonempty set, let C be a finite set of constant symbols denoting arbitrary elements of D, and let S and T be an arbitrary finite set of finite-arity relations on D. We denote the problem of determining the satisfiability of finite conjunctions of relations in S applied to variables (to variables and symbols in C) by SAT(S) (by SATc(S).) Here, we study simultaneously the complexity of decision, counting, maximization and approximate maximization problems, for unquantified, quantified and stochastically quantified formulas. We present simple yet general techniques to characterize simultaneously, the complexity or efficient approximability of a number of versions/variants of the problems SAT(S), Q-SAT(S), S-SAT(S),MAX-Q-SAT(S) etc., for many different such D,C ,S, T. These versions/variants include decision, counting, maximization and approximate maximization problems, for unquantified, quantified and stochastically quantified formulas. Our unified approach is based on the following two basic concepts: (i) strongly-local replacements/reductions and (ii) relational/algebraic represent ability. Some of the results extend the earlier results in [Pa85,LMP99,CF+93,CF+94O]u r techniques and results reported here also provide significant steps towards obtaining dichotomy theorems, for a number of the problems above, including the problems MAX-&-SAT( S), and MAX-S-SAT(S). The discovery of such dichotomy theorems, for unquantified formulas, has received significant recent attention in the literature [CF+93,CF+94,Cr95,KSW97

  19. Structural physical approximations of unphysical maps and generalized quantum measurements

    SciTech Connect (OSTI)

    Fiurasek, Jaromir

    2002-11-01

    We investigate properties of the structural physical approximation (SPA) of the partial transposition map recently introduced by Horodecki and Ekert [Phys. Rev. Lett. 89, 127902 (2002)]. We focus on the case of two-qubit states and show that in this case the map has the structure of a generalized quantum measurement followed by the preparation of a suitable output state. We also introduce SPA for a map that transforms two copies of density matrix of a single qubit onto a square of that matrix. We prove that also this map is essentially a generalized quantum measurement.

  20. Compton scattering from positronium and validity of the impulse approximation

    SciTech Connect (OSTI)

    Kaliman, Z.; Pisk, K.; Pratt, R. H.

    2011-05-15

    The cross sections for Compton scattering from positronium are calculated in the range from 1 to 100 keV incident photon energy. The calculations are based on the A{sup 2} term of the photon-electron or photon-positron interaction. Unlike in hydrogen, the scattering occurs from two centers and the interference effect plays an important role for energies below 8 keV. Because of the interference, the criterion for validity of the impulse approximation for positronium is more restrictive compared to that for hydrogen.

  1. Multigroup Free-atom Doppler-broadening Approximation. Experiment

    SciTech Connect (OSTI)

    Gray, Mark Girard

    2015-11-06

    The multigroup energy Doppler-broadening approximation agrees with continuous energy Dopplerbroadening generally to within ten percent for the total cross sections of 1H, 56Fe, and 235U at 250 lanl. Although this is probably not good enough for broadening from room temperature through the entire temperature range in production use, it is better than any interpolation scheme between temperatures proposed to date, and may be good enough for extrapolation from high temperatures. The method deserves further study since additional improvements are possible.

  2. Renewable Heat NY

    Office of Energy Efficiency and Renewable Energy (EERE)

    NOTE: On August 2015, NYSERDA increased the incentive levels for technologies offered under the Renewable Heat NY program. In general, new incentives fund up to 45% of the total project cost, which...

  3. Passive solar heating analysis

    SciTech Connect (OSTI)

    Balcomb, J.D.; Jones, R.W.; Mc Farland, R.D.; Wray, W.O.

    1984-01-01

    This book discusses about the design of solar heating systems. The terms and symbols are clearly defined. Step-by-step procedures are indicated. Worked examples are given with tables, graphs, appendixes.

  4. Heat exchange apparatus

    DOE Patents [OSTI]

    Degtiarenko, Pavel V.

    2003-08-12

    A heat exchange apparatus comprising a coolant conduit or heat sink having attached to its surface a first radial array of spaced-apart parallel plate fins or needles and a second radial array of spaced-apart parallel plate fins or needles thermally coupled to a body to be cooled and meshed with, but not contacting the first radial array of spaced-apart parallel plate fins or needles.

  5. Heat flux limiting sleeves

    DOE Patents [OSTI]

    Harris, William G. (Tampa, FL)

    1985-01-01

    A heat limiting tubular sleeve extending over only a portion of a tube having a generally uniform outside diameter, the sleeve being open on both ends, having one end thereof larger in diameter than the other end thereof and having a wall thickness which decreases in the same direction as the diameter of the sleeve decreases so that the heat transfer through the sleeve and tube is less adjacent the large diameter end of the sleeve than adjacent the other end thereof.

  6. Freezable heat pipe

    DOE Patents [OSTI]

    Ernst, Donald M.; Sanzi, James L.

    1981-02-03

    A heat pipe whose fluid can be repeatedly frozen and thawed without damage to the casing. An additional part is added to a conventional heat pipe. This addition is a simple porous structure, such as a cylinder, self-supporting and free standing, which is dimensioned with its diameter not spanning the inside transverse dimension of the casing, and with its length surpassing the depth of maximum liquid.

  7. Savannah River reactor process water heat exchanger tube structural integrity margin Task Number 92-005-1

    SciTech Connect (OSTI)

    Mertz, G.E.; Barnes, D.M.; Sindelar, R.L.

    1992-02-01

    Twelve process water heat exchangers are designed to remove heat generated in the reactor tank. Each heat exchanger has approximately 9000, 1/2 inch diameter {times} 0.049 inches thick tubes. Minimum structural tubing requirements and the leak rate through postulated tubing defects are developed in this report A comparison of the structural requirements and the defect size calculated to produce leak rates of 0.5 lbs./day demonstrate adequate structural margins against gross tube rupture. Commercial nuclear experience with pressurized water reactor (PWR) steam generator plugging criteria are used for guidance in performing this analysis. It is important to note that the SRS reactors are low energy systems with normal operating pressures of 203 psig at 130{degree}F while the PWR is a high energy system with operating pressures near 2200 psig at 600{degree}F. Clearly the PVM steam generator has loadings which are more severe than the SRS heat exchangers. Consistent with the Regulatory Guide 1.121 criteria both wastage (wall thinning) and cracking are addressed. Structural limits on wall thinning and crack size are developed to preclude gross rupture. ASME Section XI criteria, with the factors of safety recommended by Regulatory Guide 1.121 are used to develop the allowable crack size criteria. Normal operating conditions (pressure, dead weight, and hydraulic drag) are considered with seismic and water hammer accident conditions. Both the wall thinning and crack size criteria are developed for the end-of-evaluation period. Allowances for corrosion, wear, or crack growth have not been included in this analysis Structurally, the tubing is over designed and can tolerate large defects with adequate margins against gross rupture. The structural margins of heat exchanger tubing are evident by contrasting the tubing`s structural capacity, per the ASME Code, with its operating conditions/configuration.

  8. Savannah River reactor process water heat exchanger tube structural integrity margin Task Number 92-005-1

    SciTech Connect (OSTI)

    Mertz, G.E.; Barnes, D.M.; Sindelar, R.L.

    1992-02-01

    Twelve process water heat exchangers are designed to remove heat generated in the reactor tank. Each heat exchanger has approximately 9000, 1/2 inch diameter {times} 0.049 inches thick tubes. Minimum structural tubing requirements and the leak rate through postulated tubing defects are developed in this report A comparison of the structural requirements and the defect size calculated to produce leak rates of 0.5 lbs./day demonstrate adequate structural margins against gross tube rupture. Commercial nuclear experience with pressurized water reactor (PWR) steam generator plugging criteria are used for guidance in performing this analysis. It is important to note that the SRS reactors are low energy systems with normal operating pressures of 203 psig at 130{degree}F while the PWR is a high energy system with operating pressures near 2200 psig at 600{degree}F. Clearly the PVM steam generator has loadings which are more severe than the SRS heat exchangers. Consistent with the Regulatory Guide 1.121 criteria both wastage (wall thinning) and cracking are addressed. Structural limits on wall thinning and crack size are developed to preclude gross rupture. ASME Section XI criteria, with the factors of safety recommended by Regulatory Guide 1.121 are used to develop the allowable crack size criteria. Normal operating conditions (pressure, dead weight, and hydraulic drag) are considered with seismic and water hammer accident conditions. Both the wall thinning and crack size criteria are developed for the end-of-evaluation period. Allowances for corrosion, wear, or crack growth have not been included in this analysis Structurally, the tubing is over designed and can tolerate large defects with adequate margins against gross rupture. The structural margins of heat exchanger tubing are evident by contrasting the tubing's structural capacity, per the ASME Code, with its operating conditions/configuration.

  9. Beyond the random phase approximation: Stimulated Brillouin backscatter for finite laser coherence times

    SciTech Connect (OSTI)

    Korotkevich, Alexander O.; Lushnikov, Pavel M.; Rose, Harvey A.

    2015-01-15

    We developed a linear theory of backward stimulated Brillouin scatter (BSBS) of a spatially and temporally random laser beam relevant for laser fusion. Our analysis reveals a new collective regime of BSBS (CBSBS). Its intensity threshold is controlled by diffraction, once cT{sub c} exceeds a laser speckle length, with T{sub c} the laser coherence time. The BSBS spatial gain rate is approximately the sum of that due to CBSBS, and a part which is independent of diffraction and varies linearly with T{sub c}. The CBSBS spatial gain rate may be reduced significantly by the temporal bandwidth of KrF-based laser systems compared to the bandwidth currently available to temporally smoothed glass-based laser systems.

  10. Intrinsically irreversible heat engine

    DOE Patents [OSTI]

    Wheatley, J.C.; Swift, G.W.; Migliori, A.

    1984-01-01

    A class of heat engines based on an intrinsically irreversible heat transfer process is disclosed. In a typical embodiment the engine comprises a compressible fluid that is cyclically compressed and expanded while at the same time being driven in reciprocal motion by a positive displacement drive means. A second thermodynamic medium is maintained in imperfect thermal contact with the fluid and bears a broken thermodynamic symmetry with respect to the fluid. The second thermodynamic medium is a structure adapted to have a low fluid flow impedance with respect to the compressible fluid, and which is further adapted to be in only moderate thermal contact with the fluid. In operation, thermal energy is pumped along the second medium due to a phase lag between the cyclical heating and cooling of the fluid and the resulting heat conduction between the fluid and the medium. In a preferred embodiment the engine comprises an acoustical drive and a housing containing a gas which is driven at a resonant frequency so as to be maintained in a standing wave. Operation of the engine at acoustic frequencies improves the power density and coefficient of performance. The second thermodynamic medium can be coupled to suitable heat exchangers to utilize the engine as a simple refrigeration device having no mechanical moving parts. Alternatively, the engine is reversible in function so as to be utilizable as a prime mover by coupling it to suitable sources and sinks of heat.

  11. Intrinsically irreversible heat engine

    DOE Patents [OSTI]

    Wheatley, John C.; Swift, Gregory W.; Migliori, Albert

    1984-01-01

    A class of heat engines based on an intrinsically irreversible heat transfer process is disclosed. In a typical embodiment the engine comprises a compressible fluid that is cyclically compressed and expanded while at the same time being driven in reciprocal motion by a positive displacement drive means. A second thermodynamic medium is maintained in imperfect thermal contact with the fluid and bears a broken thermodynamic symmetry with respect to the fluid. the second thermodynamic medium is a structure adapted to have a low fluid flow impedance with respect to the compressible fluid, and which is further adapted to be in only moderate thermal contact with the fluid. In operation, thermal energy is pumped along the second medium due to a phase lag between the cyclical heating and cooling of the fluid and the resulting heat conduction between the fluid and the medium. In a preferred embodiment the engine comprises an acoustical drive and a housing containing a gas which is driven at a resonant frequency so as to be maintained in a standing wave. Operation of the engine at acoustic frequencies improves the power density and coefficient of performance. The second thermodynamic medium can be coupled to suitable heat exchangers to utilize the engine as a simple refrigeration device having no mechanical moving parts. Alternatively, the engine is reversible in function so as to be utilizable as a prime mover by coupling it to suitable sources and sinks of heat.

  12. Convective heat flow probe

    DOE Patents [OSTI]

    Dunn, J.C.; Hardee, H.C.; Striker, R.P.

    1984-01-09

    A convective heat flow probe device is provided which measures heat flow and fluid flow magnitude in the formation surrounding a borehole. The probe comprises an elongate housing adapted to be lowered down into the borehole; a plurality of heaters extending along the probe for heating the formation surrounding the borehole; a plurality of temperature sensors arranged around the periphery of the probe for measuring the temperature of the surrounding formation after heating thereof by the heater elements. The temperature sensors and heater elements are mounted in a plurality of separate heater pads which are supported by the housing and which are adapted to be radially expanded into firm engagement with the walls of the borehole. The heat supplied by the heater elements and the temperatures measured by the temperature sensors are monitored and used in providing the desired measurements. The outer peripheral surfaces of the heater pads are configured as segments of a cylinder and form a full cylinder when taken together. A plurality of temperature sensors are located on each pad so as to extend along the length and across the width thereof, with a heating element being located in each pad beneath the temperature sensors. An expansion mechanism driven by a clamping motor provides expansion and retraction of the heater pads and expandable packet-type seals are provided along the probe above and below the heater pads.

  13. Convective heat flow probe

    DOE Patents [OSTI]

    Dunn, James C.; Hardee, Harry C.; Striker, Richard P.

    1985-01-01

    A convective heat flow probe device is provided which measures heat flow and fluid flow magnitude in the formation surrounding a borehole. The probe comprises an elongate housing adapted to be lowered down into the borehole; a plurality of heaters extending along the probe for heating the formation surrounding the borehole; a plurality of temperature sensors arranged around the periphery of the probe for measuring the temperature of the surrounding formation after heating thereof by the heater elements. The temperature sensors and heater elements are mounted in a plurality of separate heater pads which are supported by the housing and which are adapted to be radially expanded into firm engagement with the walls of the borehole. The heat supplied by the heater elements and the temperatures measured by the temperature sensors are monitored and used in providing the desired measurements. The outer peripheral surfaces of the heater pads are configured as segments of a cylinder and form a full cylinder when taken together. A plurality of temperature sensors are located on each pad so as to extend along the length and across the width thereof, with a heating element being located in each pad beneath the temperature sensors. An expansion mechanism driven by a clamping motor provides expansion and retraction of the heater pads and expandable packer-type seals are provided along the probe above and below the heater pads.

  14. Radial flow heat exchanger

    DOE Patents [OSTI]

    Valenzuela, Javier

    2001-01-01

    A radial flow heat exchanger (20) having a plurality of first passages (24) for transporting a first fluid (25) and a plurality of second passages (26) for transporting a second fluid (27). The first and second passages are arranged in stacked, alternating relationship, are separated from one another by relatively thin plates (30) and (32), and surround a central axis (22). The thickness of the first and second passages are selected so that the first and second fluids, respectively, are transported with laminar flow through the passages. To enhance thermal energy transfer between first and second passages, the latter are arranged so each first passage is in thermal communication with an associated second passage along substantially its entire length, and vice versa with respect to the second passages. The heat exchangers may be stacked to achieve a modular heat exchange assembly (300). Certain heat exchangers in the assembly may be designed slightly differently than other heat exchangers to address changes in fluid properties during transport through the heat exchanger, so as to enhance overall thermal effectiveness of the assembly.

  15. Intrinsically irreversible heat engine

    DOE Patents [OSTI]

    Wheatley, J.C.; Swift, G.W.; Migliori, A.

    1984-12-25

    A class of heat engines based on an intrinsically irreversible heat transfer process is disclosed. In a typical embodiment the engine comprises a compressible fluid that is cyclically compressed and expanded while at the same time being driven in reciprocal motion by a positive displacement drive means. A second thermodynamic medium is maintained in imperfect thermal contact with the fluid and bears a broken thermodynamic symmetry with respect to the fluid. The second thermodynamic medium is a structure adapted to have a low fluid flow impedance with respect to the compressible fluid, and which is further adapted to be in only moderate thermal contact with the fluid. In operation, thermal energy is pumped along the second medium due to a phase lag between the cyclical heating and cooling of the fluid and the resulting heat conduction between the fluid and the medium. In a preferred embodiment the engine comprises an acoustical drive and a housing containing a gas which is driven at a resonant frequency so as to be maintained in a standing wave. Operation of the engine at acoustic frequencies improves the power density and coefficient of performance. The second thermodynamic medium can be coupled to suitable heat exchangers to utilize the engine as a simple refrigeration device having no mechanical moving parts. Alternatively, the engine is reversible in function so as to be utilizable as a prime mover by coupling it to suitable sources and sinks of heat. 11 figs.

  16. Roadmap for Process Heating Technology

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... Glass * Metal (ferrous and non- ferrous * Resin and plastic * Heat forming * Thermal forming * Paint and organic ... process heating into the Industries of the Future framework. ...

  17. Geothermal Heat Pump Manufacturing Activities

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    Type of Activity 2008 2009 Geothermal Heat Pump or System Design 17 17 Prototype Geothermal Heat Pump Development 12 13 Prototype Systems Geothermal Development 5 7 Wholesale ...

  18. Heat Pump Swimming Pool Heaters

    Broader source: Energy.gov [DOE]

    If you want an energy-efficient way to heat your swimming pool, consider using a heat pump pool heater in mild climates.

  19. Water Heating | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Public Services Homes Water Heating Water Heating Infographic: Water Heaters 101 Infographic: Water Heaters 101 Everything you need to know about saving money on water...

  20. Heating Oil and Propane Update

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Holiday Release Schedule The Heating Oil and Propane Update is produced during the winter heating season, which extends from October through March of each year. The standard ...

  1. Geothermal Heat Pump Manufacturing Activities

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    Geothermal heat pump shipments by model type, 2000 - 2009 (number of units) ARI-320 ... Administration (EIA), Form EIA-902, "Annual Geothermal Heat Pump Manufacturers Survey."

  2. NGNP Process Heat Utilization: Liquid Metal Phase Change Heat Exchanger

    SciTech Connect (OSTI)

    Piyush Sabharwall; Mike Patterson; Vivek Utgikar; Fred Gunnerson

    2008-09-01

    One key long-standing issue that must be overcome to fully realize the successful growth of nuclear power is to determine other benefits of nuclear energy apart from meeting the electricity demands. The Next Generation Nuclear Plant (NGNP) will most likely be producing electricity and heat for the production of hydrogen and/or oil retrieval from oil sands and oil shale to help in our national pursuit of energy independence. For nuclear process heat to be utilized, intermediate heat exchange is required to transfer heat from the NGNP to the hydrogen plant or oil recovery field in the most efficient way possible. Development of nuclear reactor - process heat technology has intensified the interest in liquid metals as heat transfer media because of their ideal transport properties. Liquid metal heat exchangers are not new in practical applications. An important rational for considering liquid metals is the potential convective heat transfer is among the highest known. Thus explains the interest in liquid metals as coolant for intermediate heat exchange from NGNP. For process heat it is desired that, intermediate heat exchangers (IHX) transfer heat from the NGNP in the most efficient way possible. The production of electric power at higher efficiency via the Brayton Cycle, and hydrogen production, requires both heat at higher temperatures and high effectiveness compact heat exchangers to transfer heat to either the power or process cycle. Compact heat exchangers maximize the heat transfer surface area per volume of heat exchanger; this has the benefit of reducing heat exchanger size and heat losses. High temperature IHX design requirements are governed in part by the allowable temperature drop between the outlet and inlet of the NGNP. In order to improve the characteristics of heat transfer, liquid metal phase change heat exchangers may be more effective and efficient. This paper explores the overall heat transfer characteristics and pressure drop of the phase change

  3. A multiscale two-point flux-approximation method

    SciTech Connect (OSTI)

    Myner, Olav Lie, Knut-Andreas

    2014-10-15

    A large number of multiscale finite-volume methods have been developed over the past decade to compute conservative approximations to multiphase flow problems in heterogeneous porous media. In particular, several iterative and algebraic multiscale frameworks that seek to reduce the fine-scale residual towards machine precision have been presented. Common for all such methods is that they rely on a compatible primaldual coarse partition, which makes it challenging to extend them to stratigraphic and unstructured grids. Herein, we propose a general idea for how one can formulate multiscale finite-volume methods using only a primal coarse partition. To this end, we use two key ingredients that are computed numerically: (i) elementary functions that correspond to flow solutions used in transmissibility upscaling, and (ii) partition-of-unity functions used to combine elementary functions into basis functions. We exemplify the idea by deriving a multiscale two-point flux-approximation (MsTPFA) method, which is robust with regards to strong heterogeneities in the permeability field and can easily handle general grids with unstructured fine- and coarse-scale connections. The method can easily be adapted to arbitrary levels of coarsening, and can be used both as a standalone solver and as a preconditioner. Several numerical experiments are presented to demonstrate that the MsTPFA method can be used to solve elliptic pressure problems on a wide variety of geological models in a robust and efficient manner.

  4. Energy Performance Ratings for Windows, Doors, and Skylights...

    Energy Savers [EERE]

    The NFRC label can be found on all ENERGY STAR qualified window, door, and skylight ... U-factor is the rate at which a window, door, or skylight conducts non-solar heat flow. ...

  5. UF{sub 6} pressure excursions during cylinder heating

    SciTech Connect (OSTI)

    Brown, P.G.

    1991-12-31

    As liquid UF{sub 6} inside a cylinder changes from a liquid to a solid, it forms a porous solid which occupies approximately the same volume as that of the liquid before cooling. Simultaneously as the liquid cools, UF{sub 6} vapor in the cylinder ullage above the liquid desublimes on the upper region of the inner cylinder wall. This solid is a dense, glass-like material which can accumulate to a significant thickness. The thickness of the solid coating on the upper cylinder wall and directly behind the cylinder valve area will vary depending on the conditions during the cooling stage. The amount of time lapsed between UF{sub 6} solidification and UF{sub 6} liquefaction can also affect the UF{sub 6} coating. This is due to the daily ambient heat cycle causing the coating to sublime from the cylinder wall to cooler areas, thus decreasing the thickness. Structural weakening of the dense UF{sub 6} layer also occurs due to cylinder transport vibration and thermal expansion. During cylinder heating, the UF{sub 6} nearest the cylinder wall will liquefy first. As the solid coating behind the cylinder valve begins to liquefy, it results in increased pressure depending upon the available volume for expansion. At the Paducah Gaseous Diffusion Plant (PGDP) during the liquefaction of the UF{sub 6} in cylinders in the UF{sub 6} feed and sampling autoclaves, this pressure increase has resulted in the activation of the systems rupture discs which are rated at 100 pounds per square inch differential.

  6. Method of extracting heat from dry geothermal reservoirs

    DOE Patents [OSTI]

    Potter, R.M.; Robinson, E.S.; Smith, M.C.

    1974-01-22

    Hydraulic fracturing is used to interconnect two or more holes that penetrate a previously dry geothermal reservoir, and to produce within the reservoir a sufficiently large heat-transfer surface so that heat can be extracted from the reservoir at a usefully high rate by a fluid entering it through one hole and leaving it through another. Introduction of a fluid into the reservoir to remove heat from it and establishment of natural (unpumped) convective circulation through the reservoir to accomplish continuous heat removal are important and novel features of the method. (auth)

  7. Geothermal district heating and cooling in Vicenza, Italy

    SciTech Connect (OSTI)

    Leoni, P.

    1995-06-01

    The discovery of a large low-enthalpy geothermal water reservoir under the city of Vicenza (110,000 people) in northern Italy, through an oil prospecting venture, opened up the opportunity to install a district heating system with low energy consumption. Although the geothermal water is at 67{degrees}C, this is insufficient for heating the city`s commercial and residential buildings using their existing high-temperature heat distribution systems. Heat pumps are, therefore, used to obtain optimum useful heat energy from the geothermal source. Experience so far suggests that the system can reduce energy consumption by up to 60%, or 3885 MWh/year. The 2000 m deep well was completed in 1983 and is the first such well in Italy to be located within an urban area, making it ideal as a heat source for a district heating system. It produces 100 m{sup 3}/h of low salt-content water. The {open_quotes}Vicenza{close_quotes} geothermal heating and cooling project was developed by {open_quotes}Aziende Industriali Muncipalizzate{close_quotes} from 1988 to 1991, a utility company owned by the city of Vicenza, with the purpose of distributing approximately 40,000 MWh year to residential and commercial buildings. The project includes the installation of a power plant, and a district heating and cooling network. A reduction in the consumption of conventional fuels both for heating and domestic water has been achieved through a highly-efficient thermodynamic system based on reversible heat pumps. The system provides heating in the winter and air conditioning in summer.

  8. Correction of the near threshold behavior of electron collisional excitation cross-sections in the plane-wave Born approximation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kilcrease, D. P.; Brookes, S.

    2013-08-19

    The modeling of NLTE plasmas requires the solution of population rate equations to determine the populations of the various atomic levels relevant to a particular problem. The equations require many cross sections for excitation, de-excitation, ionization and recombination. Additionally, a simple and computational fast way to calculate electron collisional excitation cross-sections for ions is by using the plane-wave Born approximation. This is essentially a high-energy approximation and the cross section suffers from the unphysical problem of going to zero near threshold. Various remedies for this problem have been employed with varying degrees of success. We present a correction procedure formore » the Born cross-sections that employs the Elwert–Sommerfeld factor to correct for the use of plane waves instead of Coulomb waves in an attempt to produce a cross-section similar to that from using the more time consuming Coulomb Born approximation. We compare this new approximation with other, often employed correction procedures. Furthermore, we also look at some further modifications to our Born Elwert procedure and its combination with Y.K. Kim's correction of the Coulomb Born approximation for singly charged ions that more accurately approximate convergent close coupling calculations.« less

  9. Heat exchanger device and method for heat removal or transfer

    DOE Patents [OSTI]

    Koplow, Jeffrey P

    2013-12-10

    Systems and methods for a forced-convection heat exchanger are provided. In one embodiment, heat is transferred to or from a thermal load in thermal contact with a heat conducting structure, across a narrow air gap, to a rotating heat transfer structure immersed in a surrounding medium such as air.

  10. Heat exchanger device and method for heat removal or transfer

    DOE Patents [OSTI]

    Koplow, Jeffrey P.

    2012-07-24

    Systems and methods for a forced-convection heat exchanger are provided. In one embodiment, heat is transferred to or from a thermal load in thermal contact with a heat conducting structure, across a narrow air gap, to a rotating heat transfer structure immersed in a surrounding medium such as air.

  11. Heat exchanger device and method for heat removal or transfer

    SciTech Connect (OSTI)

    Koplow, Jeffrey P

    2015-03-24

    Systems and methods for a forced-convection heat exchanger are provided. In one embodiment, heat is transferred to or from a thermal load in thermal contact with a heat conducting structure, across a narrow air gap, to a rotating heat transfer structure immersed in a surrounding medium such as air.

  12. Heat exchanger device and method for heat removal or transfer

    SciTech Connect (OSTI)

    Koplow, Jeffrey P.

    2015-12-08

    Systems and methods for a forced-convection heat exchanger are provided. In one embodiment, heat is transferred to or from a thermal load in thermal contact with a heat conducting structure, across a narrow air gap, to a rotating heat transfer structure immersed in a surrounding medium such as air.

  13. Approximate Weighted Matching On Emerging Manycore and Multithreaded Architectures

    SciTech Connect (OSTI)

    Halappanavar, Mahantesh; Feo, John T.; Villa, Oreste; Tumeo, Antonino; Pothen, Alex

    2012-11-30

    Graph matching is a prototypical combinatorial problem with many applications in computer science and scientific computing, but algorithms for computing optimal matchings are challenging to parallelize. Approximate matching algorithms provide an alternate route for parallelization, and in many contexts compute near-optimal matchings for large-scale graphs. We present sharedmemory parallel implementations for computing half-approximate weighted matching on state-of-the-art multicore (Intel Nehalem and AMD Magny-Cours), manycore (Nvidia Tesla and Nvidia Fermi) and massively multithreaded (Cray XMT) platforms. We provide two implementations: the first implementation uses shared work queues, and is suited to all these platforms; the second implementation is based on dataflow principles, and exploits the architectural features of the Cray XMT. Using a carefully chosen dataset that exhibits characteristics from a wide range of real-world applications, we show scalable performance across different platforms. In particular, for one instance of the input, an R-MAT graph (RMAT-G), we show speedups of: about 32 on 48 cores of an AMD Magny-Cours; 7 on 8 cores of Intel Nehalem; 3 on Nvidia Tesla and 10 on Nvidia Fermi relative to one core of Intel Nehalem; and 60 on 128 processors of Cray XMT. We demonstrate good weak and strong scaling for graphs with up to a billion edges using up to 12, 800 threads. Given the breadth of this work, we focus on simplicity and portability of software rather than excessive fine-tuning for each platform. To the best of our knowledge, this is the first such large-scale study of the half-approximate weighted matching problem on shared-memory platforms. Driven by the critical enabling role of combinatorial algorithms such as matching in scientific computing and the emergence of informatics applications, there is a growing demand to support irregular computations on current and future computing platforms. In this context, we evaluate the capability

  14. BP-18 Rate Proceeding

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Skip navigation links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases BP-18 Rate Case Related Publications Meetings...

  15. BP-12 Rate Case

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Skip navigation links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases BP-18 Rate Case Related Publications Meetings...

  16. BP-16 Rate Case

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Skip navigation links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases BP-18 Rate Case Related Publications Meetings...

  17. Before a Rate Case

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases BP-18 Rate Case Related Publications Meetings and Workshops Customer...

  18. Rating Agency Reports

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Liabilities Financial Plan Financial Public Processes Asset Management Cost Verification Process Rate Cases Rate Information Residential Exchange Program Surplus Power Sales...

  19. 2012 Transmission Rate Schedules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2014 Transmission, Ancillary, and Control Area Service Rate Schedules and General Rate Schedule Provisions (FY 2014-2015) October 2013 United States Department of Energy...

  20. Analytic derivation of an approximate SU(3) symmetry inside the symmetry triangle of the interacting boson approximation model

    SciTech Connect (OSTI)

    Bonatsos, Dennis; Karampagia, S.; Casten, R. F.

    2011-05-15

    Using a contraction of the SU(3) algebra to the algebra of the rigid rotator in the large-boson-number limit of the interacting boson approximation (IBA) model, a line is found inside the symmetry triangle of the IBA, along which the SU(3) symmetry is preserved. The line extends from the SU(3) vertex to near the critical line of the first-order shape/phase transition separating the spherical and prolate deformed phases, and it lies within the Alhassid-Whelan arc of regularity, the unique valley of regularity connecting the SU(3) and U(5) vertices in the midst of chaotic regions. In addition to providing an explanation for the existence of the arc of regularity, the present line represents an example of an analytically determined approximate symmetry in the interior of the symmetry triangle of the IBA. The method is applicable to algebraic models possessing subalgebras amenable to contraction. This condition is equivalent to algebras in which the equilibrium ground state and its rotational band become energetically isolated from intrinsic excitations, as typified by deformed solutions to the IBA for large numbers of valence nucleons.

  1. Surface wake in the random-phase approximation

    SciTech Connect (OSTI)

    Garcia de Abajo, F.J. ); Echenique, P.M. )

    1993-11-01

    The scalar-electric-potential distribution set up by an ion traveling in the vicinity of a plane solid-vacuum interface, that is, the surface-wake potential, is investigated with the specular-reflection model to describe the response of the surface and with the random-phase approximation for the dielectric function of the bulk material. This permits us to address the study of the low-velocity surface wake: the static potential is found to have a dip at the position of the ion; that dip is shifted towards the direction opposite to the velocity vector for velocities smaller than the threshold of creation of plasmons ([approx]1.3[ital v][sub [ital F

  2. Above-threshold ionization beyond the dipole approximation

    SciTech Connect (OSTI)

    Klaiber, Michael; Hatsagortsyan, Karen Z.; Keitel, Christoph H.

    2005-03-01

    A generalization of the analytical theory of above-threshold ionization in the single active electron approximation is developed while taking into account leading non-dipole and relativistic corrections in the starting Hamiltonian. Special interest is placed on the high energy part of the photoelectron spectrum which consists of a plateau and a characteristic cutoff. It is shown that the correction due to the magnetic component of the laser field gives rise to a decrease of the plateau height, an increase of the maximal cutoff energy, and a drift of the emitted electrons in propagation direction of the laser field. Furthermore, the influence of the relativistic mass shift may become non-neglible by reducing the cutoff energy significantly. Spin effects or the Zitterbewegung play a comparably minor role in the investigated parameter regime of suboptical frequencies and high but not ultra-high laser intensities.

  3. Mixed series in ultraspherical polynomials and their approximation properties

    SciTech Connect (OSTI)

    Sharapudinov, I I

    2003-04-30

    New (mixed) series in ultraspherical polynomials P{sub n}{sup {alpha}}{sup ,{alpha}}(x) are introduced. The basic difference between a mixed series in the polynomials P{sub n}{sup {alpha}}{sup ,{alpha}}(x) and a Fourier series in the same polynomials is as follows: a mixed series contains terms of the form (2{sup r}f{sub r,k}{sup {alpha}})/(k+2{alpha}){sup [r]}) P{sub k+r}{sup {alpha}}{sup -r,{alpha}}{sup -r}(x), where 1{<=}r is an integer and f{sub r,k}{sup {alpha}} is the kth Fourier coefficient of the derivative f{sup (r)}(x) with respect to the ultraspherical polynomials P{sub k}{sup {alpha}}{sup ,{alpha}}(x). It is shown that the partial sums Y{sub n+2r}{sup {alpha}}(f,x) of a mixed series in the polynomial P{sub k}{sup {alpha}}{sup ,{alpha}}(x) contrast favourably with Fourier sums S{sub n}{sup {alpha}}(f,x) in the same polynomials as regards their approximation properties in classes of differentiable and analytic functions, and also in classes of functions of variable smoothness. In particular, the Y{sub n+2r}{sup {alpha}}(f,x) can be used for the simultaneous approximation of a function f(x) and its derivatives of orders up to (r- 1), whereas the S{sub n}{sup {alpha}}(f,x) are not suitable for this purpose.

  4. Heat exchanger restart evaluation

    SciTech Connect (OSTI)

    Morrison, J.M.; Hirst, C.W.; Lentz, T.F.

    1992-02-28

    On December 24, 1991, the K-Reactor was in the shutdown mode with full AC process water flow and full cooling water flow. Safety rod testing was being performed as part of the power ascension testing program. The results of cooling water samples indicated tritium concentrations higher than allowable. Further sampling and testing confirmed a Process Water System to Cooling Water System leak in heat exchanger 4A (HX 4A). The heat exchanger was isolated and the plant shutdown. Heat exchanger 4kA was removed from the plant and moved to C-Area prior to performing examinations and diagnostic testing. This included locating and identifying the leaking tube or tubes, eddy current examination of the leaking tube and a number of adjacent tubes, visually inspecting the leaking tube from both the inside as well as the area surrounding the failure mechanism. In addition ten other tubes that either exhibited eddy current indications or would represent a baseline condition were removed from heat exchanger 4A for metallurgical examination. Additional analysis and review of heat exchanger leakage history was performed to determine if there are any patterns which can be used for predictive purposes. Compensatory actions have been taken to improve the sensitivity and response time to any future events of this type. The results of these actions are summarized herein.

  5. Heat exchanger restart evaluation

    SciTech Connect (OSTI)

    Morrison, J.M.; Hirst, C.W.; Lentz, T.F.

    1992-03-18

    On December 24, 1991, the K-Reactor was in the shutdown mode with full AC process water flow and full cooling water flow. Safety rod testing was being performed as part of the power ascension testing program. The results of cooling water samples indicated tritium concentrations higher than allowable. Further sampling and testing confirmed a Process Water System to Cooling Water System leak in heat exchanger 4A (HX 4A). The heat exchanger was isolated and the plant shutdown. Heat exchanger 4A was removed from the plant and moved to C-Area prior to performing examinations and diagnostic testing. This included locating and identifying the leaking tube or tubes, eddy current examination of the leaking tube and a number of adjacent tubes, visually inspecting the leaking tube from both the inside as well as the area surrounding the identified tube. The leaking tube was removed and examined metallurgically to determine the failure mechanism. In addition ten other tubes that either exhibited eddy current indications or would represent a baseline condition were removed from heat exchanger 4A for metallurgical examination. Additional analysis and review of heat exchanger leakage history was performed to determine if there are any patterns which can be used for predictive purposes. Compensatory actions have been taken to improve the sensitivity and response time to any future events of this type. The results of these actions are summary herein.

  6. Heat exchanger restart evaluation

    SciTech Connect (OSTI)

    Morrison, J.M.; Hirst, C.W.; Lentz, T.F.

    1992-03-18

    On December 24, 1991, the K-Reactor was in the shutdown mode with full AC process water flow and full cooling water flow. Safety rod testing was being performed as part of the power ascension testing program. The results of cooling water samples indicated tritium concentrations higher than allowable. Further sampling and testing confirmed a Process Water System to Cooling Water System leak in heat exchanger 4A (HX 4A). The heat exchanger was isolated and the plant shutdown. Heat exchanger 4A was removed from the plant and moved to C-Area prior to performing examinations and diagnostic testing. This included locating and identifying the leaking tube or tubes, eddy current examination of the leaking tube and a number of adjacent tubes, visually inspecting the leaking tube from both the inside as well as the area surrounding the identified tube. The leaking tube was removed and examined metallurgically to determine the failure mechanism. In addition ten other tubes that either exhibited eddy current indications or would represent a baseline condition were removed from heat exchanger 4A for metallurgical examination. Additional analysis and review of heat exchanger leakage history was performed to determine if there are any patterns which can be used for predictive purposes. Compensatory actions have been taken to improve the sensitivity and response time to any future events of this type. The results of these actions are summarized.

  7. Heat exchanger-accumulator

    DOE Patents [OSTI]

    Ecker, Amir L.

    1980-01-01

    What is disclosed is a heat exchanger-accumulator for vaporizing a refrigerant or the like, characterized by an upright pressure vessel having a top, bottom and side walls; an inlet conduit eccentrically and sealingly penetrating through the top; a tubular overflow chamber disposed within the vessel and sealingly connected with the bottom so as to define an annular outer volumetric chamber for receiving refrigerant; a heat transfer coil disposed in the outer volumetric chamber for vaporizing the liquid refrigerant that accumulates there; the heat transfer coil defining a passageway for circulating an externally supplied heat exchange fluid; transferring heat efficiently from the fluid; and freely allowing vaporized refrigerant to escape upwardly from the liquid refrigerant; and a refrigerant discharge conduit penetrating sealingly through the top and traversing substantially the length of the pressurized vessel downwardly and upwardly such that its inlet is near the top of the pressurized vessel so as to provide a means for transporting refrigerant vapor from the vessel. The refrigerant discharge conduit has metering orifices, or passageways, penetrating laterally through its walls near the bottom, communicating respectively interiorly and exteriorly of the overflow chamber for controllably carrying small amounts of liquid refrigerant and oil to the effluent stream of refrigerant gas.

  8. Set up of an experimental apparatus for the study of fragmentation of solid fuels upon severe heating

    SciTech Connect (OSTI)

    Senneca, O.; Allouis, C.; Chirone, R.; Russo, S.

    2010-04-15

    An experimental apparatus has been developed in order to perform tests of primary fragmentation of solid fuels under severe heating conditions. The device is a modified heated strip reactor, capable to reach 2000 C in less than 0.2 s. Particles are laid on the strip and pyrolysed under inert or moderately oxidizing conditions. The char particles and their fragments, generated upon pyrolysis, can be recovered and analysed to assess the fragmentation propensity of the fuel. Some preliminary experiments have been carried out on two biomass samples in order to assess the time-temperature history of particles in the experimental apparatus. In particular biomass particles of approximately 2-3 mm have been used. The temperature of the heated strip reactor in such preliminary tests was varied between 1000 and 1600 C, while the strip nominal heating rate was kept at 10{sup 4} C/s and the holding time was set at the value of 10 s. A near infrared fast camera (38,000 frames/s) has been used to measure the temperature of the heated strip and of the particles during the tests. A heat up model was developed and validated against experimental results. The model was then used to estimate the temperature gradients across particles of biomass and of coal as well. Results show that the strip of the reactor reaches the set temperature in less than 0.2 s. When particles are laid on the strip, their bottom surface, which is in physical contact with the strip, immediately reaches the set temperature value. For 1 mm coal particles the upper surface can be considered at the same temperature as well. Under the most severe conditions tested (strip temperature of 1600 C, biomass particles of 2 mm thickness) the temperature difference between the bottom and the upper face is 200 C after 3 s and drops to 100 C after 10 s. On the whole the experimental apparatus simulates uniform heating of the particles with reasonable approximation. In the next future the apparatus will be further upgraded to

  9. Method and apparatus for obtaining enhanced production rate of thermal chemical reactions

    DOE Patents [OSTI]

    Tonkovich, Anna Lee Y [Pasco, WA; Wang, Yong [Richland, WA; Wegeng, Robert S [Richland, WA; Gao, Yufei [Kennewick, WA

    2003-04-01

    The present invention is a method and apparatus (vessel) for providing a heat transfer rate from a reaction chamber through a wall to a heat transfer chamber substantially matching a local heat transfer rate of a catalytic thermal chemical reaction. The key to the invention is a thermal distance defined on a cross sectional plane through the vessel inclusive of a heat transfer chamber, reaction chamber and a wall between the chambers. The cross sectional plane is perpendicular to a bulk flow direction of the reactant stream, and the thermal distance is a distance between a coolest position and a hottest position on the cross sectional plane. The thermal distance is of a length wherein the heat transfer rate from the reaction chamber to the heat transfer chamber substantially matches the local heat transfer rate.

  10. Value of solar thermal industrial process heat

    SciTech Connect (OSTI)

    Brown, D.R.; Fassbender, L.L.; Chockie, A.D.

    1986-03-01

    This study estimated the value of solar thermal-generated industrial process heat (IPH) as a function of process heat temperature. The value of solar thermal energy is equal to the cost of producing energy from conventional fuels and equipment if the energy produced from either source provides an equal level of service. This requirement put the focus of this study on defining and characterizing conventional process heat equipment and fuels. Costs (values) were estimated for 17 different design points representing different combinations of conventional technologies, temperatures, and fuels. Costs were first estimated for median or representative conditions at each design point. The cost impact of capacity factor, efficiency, fuel escalation rate, and regional fuel price differences were then evaluated by varying each of these factors within credible ranges.

  11. Advanced Heat Transfer and Thermal Storage Fluids

    SciTech Connect (OSTI)

    Moens, L.; Blake, D.

    2005-01-01

    The design of the next generation solar parabolic trough systems for power production will require the development of new thermal energy storage options with improved economics or operational characteristics. Current heat-transfer fluids such as VP-1?, which consists of a eutectic mixture of biphenyl and diphenyl oxide, allow a maximum operating temperature of ca. 300 C, a limit above which the vapor pressure would become too high and would require pressure-rated tanks. The use of VP-1? also suffers from a freezing point around 13 C that requires heating during cold periods. One of the goals for future trough systems is the use of heat-transfer fluids that can act as thermal storage media and that allow operating temperatures around 425 C combined with lower limits around 0 C. This paper presents an outline of our latest approach toward the development of such thermal storage fluids.

  12. Guide to Geothermal Heat Pumps

    SciTech Connect (OSTI)

    2011-02-01

    Geothermal heat pumps, also known as ground source heat pumps, geoexchange, water-source, earth-coupled, and earth energy heat pumps, take advantage of this resource and represent one of the most efficient and durable options on the market to heat and cool your home.

  13. Residential heating oil prices available

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil prices available The average retail price for home heating oil is $2.41 per gallon, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region currently average $2.35 per gallon. This is Marcela Rourk with EIA, in Washington.

  14. Modular heat exchanger

    DOE Patents [OSTI]

    Culver, Donald W.

    1978-01-01

    A heat exchanger for use in nuclear reactors includes a heat exchange tube bundle formed from similar modules each having a hexagonal shroud containing a large number of thermally conductive tubes which are connected with inlet and outlet headers at opposite ends of each module, the respective headers being adapted for interconnection with suitable inlet and outlet manifold means. In order to adapt the heat exchanger for operation in a high temperature and high pressure environment and to provide access to all tube ports at opposite ends of the tube bundle, a spherical tube sheet is arranged in sealed relation across the chamber with an elongated duct extending outwardly therefrom to provide manifold means for interconnection with the opposite end of the tube bundle.

  15. Electrochemical heat engine

    DOE Patents [OSTI]

    Elliott, Guy R. B.; Holley, Charles E.; Houseman, Barton L.; Sibbitt, Jr., Wilmer L.

    1978-01-01

    Electrochemical heat engines produce electrochemical work, and mechanical motion is limited to valve and switching actions as the heat-to-work cycles are performed. The electrochemical cells of said heat engines use molten or solid electrolytes at high temperatures. One or more reactions in the cycle will generate a gas at high temperature which can be condensed at a lower temperature with later return of the condensate to electrochemical cells. Sodium, potassium, and cesium are used as the working gases for high temperature cells (above 600 K) with halogen gases or volatile halides being used at lower temperature. Carbonates and halides are used as molten electrolytes and the solid electrolyte in these melts can also be used as a cell separator.

  16. Heat transfer fluids containing nanoparticles

    DOE Patents [OSTI]

    Singh, Dileep; Routbort, Jules; Routbort, A.J.; Yu, Wenhua; Timofeeva, Elena; Smith, David S.; France, David M.

    2016-05-17

    A nanofluid of a base heat transfer fluid and a plurality of ceramic nanoparticles suspended throughout the base heat transfer fluid applicable to commercial and industrial heat transfer applications. The nanofluid is stable, non-reactive and exhibits enhanced heat transfer properties relative to the base heat transfer fluid, with only minimal increases in pumping power required relative to the base heat transfer fluid. In a particular embodiment, the plurality of ceramic nanoparticles comprise silicon carbide and the base heat transfer fluid comprises water and water and ethylene glycol mixtures.

  17. Air heating system

    DOE Patents [OSTI]

    Primeau, John J.

    1983-03-01

    A self-starting, fuel-fired, air heating system including a vapor generator, a turbine, and a condenser connected in a closed circuit such that the vapor output from the vapor generator is conducted to the turbine and then to the condenser where it is condensed for return to the vapor generator. The turbine drives an air blower which passes air over the condenser for cooling the condenser. Also, a condensate pump is driven by the turbine. The disclosure is particularly concerned with the provision of heat exchanger and circuitry for cooling the condensed fluid output from the pump prior to its return to the vapor generator.

  18. Solar industrial process heat

    SciTech Connect (OSTI)

    Lumsdaine, E.

    1981-04-01

    The aim of the assessment reported is to candidly examine the contribution that solar industrial process heat (SIPH) is realistically able to make in the near and long-term energy futures of the United States. The performance history of government and privately funded SIPH demonstration programs, 15 of which are briefly summarized, and the present status of SIPH technology are discussed. The technical and performance characteristics of solar industrial process heat plants and equipment are reviewed, as well as evaluating how the operating experience of over a dozen SIPH demonstration projects is influencing institutional acceptance and economoc projections. Implications for domestic energy policy and international implications are briefly discussed. (LEW)

  19. Acoustical heat pumping engine

    DOE Patents [OSTI]

    Wheatley, J.C.; Swift, G.W.; Migliori, A.

    1983-08-16

    The disclosure is directed to an acoustical heat pumping engine without moving seals. A tubular housing holds a compressible fluid capable of supporting an acoustical standing wave. An acoustical driver is disposed at one end of the housing and the other end is capped. A second thermodynamic medium is disposed in the housing near to but spaced from the capped end. Heat is pumped along the second thermodynamic medium toward the capped end as a consequence both of the pressure oscillation due to the driver and imperfect thermal contact between the fluid and the second thermodynamic medium. 2 figs.

  20. Acoustical heat pumping engine

    DOE Patents [OSTI]

    Wheatley, John C.; Swift, Gregory W.; Migliori, Albert

    1983-08-16

    The disclosure is directed to an acoustical heat pumping engine without moving seals. A tubular housing holds a compressible fluid capable of supporting an acoustical standing wave. An acoustical driver is disposed at one end of the housing and the other end is capped. A second thermodynamic medium is disposed in the housing near to but spaced from the capped end. Heat is pumped along the second thermodynamic medium toward the capped end as a consequence both of the pressure oscillation due to the driver and imperfect thermal contact between the fluid and the second thermodynamic medium.

  1. Heat distribution ceramic processing method

    DOE Patents [OSTI]

    Tiegs, Terry N. (Lenoir City, TN); Kiggans, Jr., James O. (Oak Ridge, TN)

    2001-01-01

    A multi-layered heat distributor system is provided for use in a microwave process. The multi-layered heat distributors includes a first inner layer of a high thermal conductivity heat distributor material, a middle insulating layer and an optional third insulating outer layer. The multi-layered heat distributor system is placed around the ceramic composition or article to be processed and located in a microwave heating system. Sufficient microwave energy is applied to provide a high density, unflawed ceramic product.

  2. Apparatus and method for controlling heat transfer between a fluidized bed and tubes immersed therein

    DOE Patents [OSTI]

    Hodges, James L. (3 Hilltop Ave., Vernon, CT 06066); Cerkanowicz, Anthony E. (8 Fieldstone Dr., Livingston, NJ 07039)

    1983-01-01

    In a fluidized bed of solid particles having one or more heat exchange tubes immersed therein, the rate of heat transfer between the fluidized particles and a fluid flowing through the immersed heat exchange tubes is controlled by rotating an arcuate shield apparatus about each tube to selectively expose various portions of the tube to the fluidized particles.

  3. Apparatus and method for controlling heat transfer between a fluidized bed and tubes immersed therein

    DOE Patents [OSTI]

    Hodges, James L. (3 Hilltop Ave., Vernon, CT 06066); Cerkanowicz, Anthony E. (8 Fieldstone Dr., Livingston, NJ 07039)

    1982-01-01

    In a fluidized bed of solid particles having one or more heat exchange tubes immersed therein, the rate of heat transfer between the fluidized particles and a fluid flowing through the immersed heat exchange tubes is controlled by rotating an arcuate shield apparatus about each tube to selectively expose various portions of the tube to the fluidized particles.

  4. Heat Transfer in Complex Fluids

    SciTech Connect (OSTI)

    Mehrdad Massoudi

    2012-01-01

    Amongst the most important constitutive relations in Mechanics, when characterizing the behavior of complex materials, one can identify the stress tensor T, the heat flux vector q (related to heat conduction) and the radiant heating (related to the radiation term in the energy equation). Of course, the expression 'complex materials' is not new. In fact, at least since the publication of the paper by Rivlin & Ericksen (1955), who discussed fluids of complexity (Truesdell & Noll, 1992), to the recently published books (Deshpande et al., 2010), the term complex fluids refers in general to fluid-like materials whose response, namely the stress tensor, is 'non-linear' in some fashion. This non-linearity can manifest itself in variety of forms such as memory effects, yield stress, creep or relaxation, normal-stress differences, etc. The emphasis in this chapter, while focusing on the constitutive modeling of complex fluids, is on granular materials (such as coal) and non-linear fluids (such as coal-slurries). One of the main areas of interest in energy related processes, such as power plants, atomization, alternative fuels, etc., is the use of slurries, specifically coal-water or coal-oil slurries, as the primary fuel. Some studies indicate that the viscosity of coal-water mixtures depends not only on the volume fraction of solids, and the mean size and the size distribution of the coal, but also on the shear rate, since the slurry behaves as shear-rate dependent fluid. There are also studies which indicate that preheating the fuel results in better performance, and as a result of such heating, the viscosity changes. Constitutive modeling of these non-linear fluids, commonly referred to as non-Newtonian fluids, has received much attention. Most of the naturally occurring and synthetic fluids are non-linear fluids, for example, polymer melts, suspensions, blood, coal-water slurries, drilling fluids, mud, etc. It should be noted that sometimes these fluids show Newtonian

  5. Heating element support clip

    DOE Patents [OSTI]

    Sawyer, William C.

    1995-01-01

    An apparatus for supporting a heating element in a channel formed in a heater base is disclosed. A preferred embodiment includes a substantially U-shaped tantalum member. The U-shape is characterized by two substantially parallel portions of tantalum that each have an end connected to opposite ends of a base portion of tantalum. The parallel portions are each substantially perpendicular to the base portion and spaced apart a distance not larger than a width of the channel and not smaller than a width of a graphite heating element. The parallel portions each have a hole therein, and the centers of the holes define an axis that is substantially parallel to the base portion. An aluminum oxide ceramic retaining pin extends through the holes in the parallel portions and into a hole in a wall of the channel to retain the U-shaped member in the channel and to support the graphite heating element. The graphite heating element is confined by the parallel portions of tantalum, the base portion of tantalum, and the retaining pin. A tantalum tube surrounds the retaining pin between the parallel portions of tantalum.

  6. Heating element support clip

    DOE Patents [OSTI]

    Sawyer, W.C.

    1995-08-15

    An apparatus for supporting a heating element in a channel formed in a heater base is disclosed. A preferred embodiment includes a substantially U-shaped tantalum member. The U-shape is characterized by two substantially parallel portions of tantalum that each have an end connected to opposite ends of a base portion of tantalum. The parallel portions are each substantially perpendicular to the base portion and spaced apart a distance not larger than a width of the channel and not smaller than a width of a graphite heating element. The parallel portions each have a hole therein, and the centers of the holes define an axis that is substantially parallel to the base portion. An aluminum oxide ceramic retaining pin extends through the holes in the parallel portions and into a hole in a wall of the channel to retain the U-shaped member in the channel and to support the graphite heating element. The graphite heating element is confined by the parallel portions of tantalum, the base portion of tantalum, and the retaining pin. A tantalum tube surrounds the retaining pin between the parallel portions of tantalum. 6 figs.

  7. Wastewater heat recovery apparatus

    DOE Patents [OSTI]

    Kronberg, J.W.

    1992-09-01

    A heat recovery system is described with a heat exchanger and a mixing valve. A drain trap includes a heat exchanger with an inner coiled tube, baffle plate, wastewater inlet, wastewater outlet, cold water inlet, and preheated water outlet. Wastewater enters the drain trap through the wastewater inlet, is slowed and spread by the baffle plate, and passes downward to the wastewater outlet. Cold water enters the inner tube through the cold water inlet and flows generally upward, taking on heat from the wastewater. This preheated water is fed to the mixing valve, which includes a flexible yoke to which are attached an adjustable steel rod, two stationary zinc rods, and a pivoting arm. The free end of the arm forms a pad which rests against a valve seat. The rods and pivoting arm expand or contract as the temperature of the incoming preheated water changes. The zinc rods expand more than the steel rod, flexing the yoke and rotating the pivoting arm. The pad moves towards the valve seat as the temperature of the preheated water rises, and away as the temperature falls, admitting a variable amount of hot water to maintain a nearly constant average process water temperature. 6 figs.

  8. Wastewater heat recovery apparatus

    DOE Patents [OSTI]

    Kronberg, James W.

    1992-01-01

    A heat recovery system with a heat exchanger and a mixing valve. A drain trap includes a heat exchanger with an inner coiled tube, baffle plate, wastewater inlet, wastewater outlet, cold water inlet, and preheated water outlet. Wastewater enters the drain trap through the wastewater inlet, is slowed and spread by the baffle plate, and passes downward to the wastewater outlet. Cold water enters the inner tube through the cold water inlet and flows generally upward, taking on heat from the wastewater. This preheated water is fed to the mixing valve, which includes a flexible yoke to which are attached an adjustable steel rod, two stationary zinc rods, and a pivoting arm. The free end of the arm forms a pad which rests against a valve seat. The rods and pivoting arm expand or contract as the temperature of the incoming preheated water changes. The zinc rods expand more than the steel rod, flexing the yoke and rotating the pivoting arm. The pad moves towards the valve seat as the temperature of the preheated water rises, and away as the temperature falls, admitting a variable amount of hot water to maintain a nearly constant average process water temperature.

  9. Absorption Heat Pumps | Department of Energy

    Energy Savers [EERE]

    Heat Pump Systems Absorption Heat Pumps Absorption Heat Pumps Absorption heat pumps are ... As in a standard heat pump, the refrigerant (in this case, ammonia) is condensed in one ...

  10. Heat exchange assembly

    DOE Patents [OSTI]

    Lowenstein, Andrew; Sibilia, Marc; Miller, Jeffrey; Tonon, Thomas S.

    2004-06-08

    A heat exchange assembly comprises a plurality of plates disposed in a spaced-apart arrangement, each of the plurality of plates includes a plurality of passages extending internally from a first end to a second end for directing flow of a heat transfer fluid in a first plane, a plurality of first end-piece members equaling the number of plates and a plurality of second end-piece members also equaling the number of plates, each of the first and second end-piece members including a recessed region adapted to fluidly connect and couple with the first and second ends of the plate, respectively, and further adapted to be affixed to respective adjacent first and second end-piece members in a stacked formation, and each of the first and second end-piece members further including at least one cavity for enabling entry of the heat transfer fluid into the plate, exit of the heat transfer fluid from the plate, or 180.degree. turning of the fluid within the plate to create a serpentine-like fluid flow path between points of entry and exit of the fluid, and at least two fluid conduits extending through the stacked plurality of first and second end-piece members for providing first fluid connections between the parallel fluid entry points of adjacent plates and a fluid supply inlet, and second fluid connections between the parallel fluid exit points of adjacent plates and a fluid discharge outlet so that the heat transfer fluid travels in parallel paths through each respective plate.

  11. Realization rates of the National Energy Audit

    SciTech Connect (OSTI)

    Berry, L.G.; Gettings, M.B.

    1998-11-01

    Engineering estimates of savings resulting from installation of energy conservation measures in homes are often greater than the savings actually realized. A brief review of prior studies of realization rates prefaces this study of rates from an engineering audit tool, NEAT, (developed for the Department of Energy`s Low-Income Weatherization Assistance Program) used in a New York state utility`s low-income program. Estimates of metered and predicted savings are compared for 49 homes taken from a data base of homes that participated in the first year of the utility`s program. Average realization rates ranging from 57% to 69% result, depending on the data quality. Detailed examinations of two houses using an alternate engineering method, the DOE-2 computer program (considered an industry standard), seem to indicate that the low realization rates mainly result from factors other than inaccuracies in the audit`s internal algorithms. Causes of the low realization rates are examined, showing that the strongest single factor linked to the low rates in this study is the use of secondary heating fuels that supplement the primary heating fuel. This study, like the other similar studies, concludes that engineering estimates are valuable tools in determining ranked lists of cost-effective weatherization measures, but may not be accurate substitutes for measured results in evaluating program performance.

  12. DOE Science Showcase - Heat Pump Research | OSTI, US Dept of...

    Office of Scientific and Technical Information (OSTI)

    HEATING PERFORMANCE GEOTHERMAL HEATING WATER SOURCE HEAT PUMPS EVALUATION DOCUMENT ... Geothermal Heat Pumps - Heating Mode Cooling Mode Animations Heat Pump Water Heaters ...

  13. Markov Jump Processes Approximating a Non-Symmetric Generalized Diffusion

    SciTech Connect (OSTI)

    Limic, Nedzad

    2011-08-15

    Consider a non-symmetric generalized diffusion X( Dot-Operator ) in Double-Struck-Capital-R {sup d} determined by the differential operator A(x) = -{Sigma}{sub ij} {partial_derivative}{sub i}a{sub ij}(x){partial_derivative}{sub j} + {Sigma}{sub i} b{sub i}(x){partial_derivative}{sub i}. In this paper the diffusion process is approximated by Markov jump processes X{sub n}( Dot-Operator ), in homogeneous and isotropic grids G{sub n} Subset-Of Double-Struck-Capital-R {sup d}, which converge in distribution in the Skorokhod space D([0,{infinity}), Double-Struck-Capital-R {sup d}) to the diffusion X( Dot-Operator ). The generators of X{sub n}( Dot-Operator ) are constructed explicitly. Due to the homogeneity and isotropy of grids, the proposed method for d{>=}3 can be applied to processes for which the diffusion tensor {l_brace}a{sub ij}(x){r_brace}{sub 11}{sup dd} fulfills an additional condition. The proposed construction offers a simple method for simulation of sample paths of non-symmetric generalized diffusion. Simulations are carried out in terms of jump processes X{sub n}( Dot-Operator ). For piece-wise constant functions a{sub ij} on Double-Struck-Capital-R {sup d} and piece-wise continuous functions a{sub ij} on Double-Struck-Capital-R {sup 2} the construction and principal algorithm are described enabling an easy implementation into a computer code.

  14. Irradiation creep of various ferritic alloys irradiated {approximately}400 C in the PFR and FFTF reactors

    SciTech Connect (OSTI)

    Toloczko, M.B.; Garner, F.A.; Eiholzer, C.R.

    1998-03-01

    Three ferritic alloys were irradiated in two fast reactors to doses of 50 dpa or more at temperatures near 400 C. One martensitic alloy, HT9, was irradiated in both the FFTF and PFR reactors. PFR is the Prototype Fast Reactor in Dourneay, Scotland, and FFTF is the Fast Flux Test Facility in Richland, WA. D57 is a developmental alloy that was irradiated in PFR only, and MA957 is a Y{sub 2}O{sub 3} dispersion-hardened ferritic alloy that was irradiated only in FFTF. These alloys exhibited little or no void swelling at {approximately}400 C. Depending on the alloy starting condition, these steels develop a variety of non-creep strains early in the irradiation that are associated with phase changes. Each of these alloys creeps at a rate that is significantly lower than that of austenitic steels irradiated in the same experiments. The creep compliance for ferritic alloys in general appears to be {approximately}0.5 {times} 10{sup {minus}6} MPa{sup {minus}1} dpa{sup {minus}1}, independent of both composition and starting state. The addition of Y{sub 2}O{sub 3} as a dispersoid does not appear to change the creep behavior.

  15. Quasi-linear heating and acceleration in bi-Maxwellian plasmas

    SciTech Connect (OSTI)

    Hellinger, Petr; Trávníček, Pavel M.

    2013-12-15

    Quasi-linear acceleration and heating rates are derived for drifting bi-Maxwellian distribution functions in a general nonrelativistic case for arbitrary wave vectors, propagation angles, and growth/damping rates. The heating rates in a proton-electron plasma due to ion-cyclotron/kinetic Alfvén and mirror waves for a wide range of wavelengths, directions of propagation, and growth or damping rates are explicitly computed.

  16. SELF HELPS ST. LUCIE RESIDENTS BEAT THE FLORIDA HEAT | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    SELF HELPS ST. LUCIE RESIDENTS BEAT THE FLORIDA HEAT SELF HELPS ST. LUCIE RESIDENTS BEAT THE FLORIDA HEAT SELF HELPS ST. LUCIE RESIDENTS BEAT THE FLORIDA HEAT In the hot Florida climate, poor insulation or inefficient equipment can have a large impact on homeowners' energy use. Because the state has some of the highest energy consumption per capita and fairly high electricity rates, summer heat waves can send Floridians' utility bills soaring. St. Lucie County in the heart of Florida's Treasure

  17. Total heat gain and the split between radiant and convective heat gain from office and laboratory equipment in buildings

    SciTech Connect (OSTI)

    Hosni, M.H.; Jones, B.W.; Sipes, J.M.; Xu, Y.

    1998-10-01

    An accurate determination of the cooling load is important in the proper sizing of air-conditioning equipment. Improvements on the thermal insulation characteristics of building materials and recent advances in building envelope systems have reduced the building cooling load from external sources. However, the number of internal cooling load sources have increased due to the addition of various office and laboratory equipment (e.g., microcomputer, monitor, printer copier, scanner, overhead projector, microwave oven, incubator, etc.). In this article, typical office and laboratory equipment such as desktop computers (with a Pentium and a 486DX2-33 processor), monitors, a copier, a laser printer, and a biological incubator are evaluated to determine the total heat gain and the split between radiant and convective heat gain from these items. In addition, two standard objects with well-defined radiant heat loss characteristics, a heated flat slab, and a heated sphere are used to verify the accuracy of measurement and data reduction procedures. The total heat gain from tested office equipment was significantly less than the name plate ratings even when operated continuously. The actual power consumption ranged from 14% to 36% of the name plate ratings. Thus, care must be taken when using equipment nameplate ratings in estimating total heat gain for air-conditioning equipment sizing.

  18. Heat Pump Water Heaters | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Heat Pump Water Heaters Heat Pump Water Heaters A diagram of a heat pump water heater. A diagram of a heat pump water heater. Most homeowners who have heat pumps use them to heat and cool their homes. But a heat pump also can be used to heat water -- either as stand-alone water heating system, or as combination water heating and space conditioning system. How They Work Heat pump water heaters use electricity to move heat from one place to another instead of generating heat directly. Therefore,

  19. Fast reactor power plant design having heat pipe heat exchanger

    DOE Patents [OSTI]

    Huebotter, P.R.; McLennan, G.A.

    1984-08-30

    The invention relates to a pool-type fission reactor power plant design having a reactor vessel containing a primary coolant (such as liquid sodium), and a steam expansion device powered by a pressurized water/steam coolant system. Heat pipe means are disposed between the primary and water coolants to complete the heat transfer therebetween. The heat pipes are vertically oriented, penetrating the reactor deck and being directly submerged in the primary coolant. A U-tube or line passes through each heat pipe, extended over most of the length of the heat pipe and having its walls spaced from but closely proximate to and generally facing the surrounding walls of the heat pipe. The water/steam coolant loop includes each U-tube and the steam expansion device. A heat transfer medium (such as mercury) fills each of the heat pipes. The thermal energy from the primary coolant is transferred to the water coolant by isothermal evaporation-condensation of the heat transfer medium between the heat pipe and U-tube walls, the heat transfer medium moving within the heat pipe primarily transversely between these walls.

  20. Fast reactor power plant design having heat pipe heat exchanger

    DOE Patents [OSTI]

    Huebotter, Paul R.; McLennan, George A.

    1985-01-01

    The invention relates to a pool-type fission reactor power plant design having a reactor vessel containing a primary coolant (such as liquid sodium), and a steam expansion device powered by a pressurized water/steam coolant system. Heat pipe means are disposed between the primary and water coolants to complete the heat transfer therebetween. The heat pipes are vertically oriented, penetrating the reactor deck and being directly submerged in the primary coolant. A U-tube or line passes through each heat pipe, extended over most of the length of the heat pipe and having its walls spaced from but closely proximate to and generally facing the surrounding walls of the heat pipe. The water/steam coolant loop includes each U-tube and the steam expansion device. A heat transfer medium (such as mercury) fills each of the heat pipes. The thermal energy from the primary coolant is transferred to the water coolant by isothermal evaporation-condensation of the heat transfer medium between the heat pipe and U-tube walls, the heat transfer medium moving within the heat pipe primarily transversely between these walls.

  1. Metal-Organic Heat Carrier Nanofluids

    SciTech Connect (OSTI)

    McGrail, B. Peter; Thallapally, Praveen K.; Blanchard, Jeremy; Nune, Satish K.; Jenks, Jeromy WJ; Dang, Liem X.

    2013-09-01

    Nanofluids, dispersions of metal or oxide nanoparticles in a base working fluid, are being intensively studied due to improvements they offer in thermal properties of the working fluid. However, these benefits have been erratically demonstrated and proven impacts on thermal conductivity are modest and well described from long-established effective medium theory. In this paper, we describe a new class of metal-organic heat carrier (MOHC) nanofluid that offers potential for a larger performance boost in thermal vapor-liquid compression cycles. MOHCs are nanophase porous coordination solids designed to reversibly uptake the working fluid molecules in which the MOHCs are suspended. Additional heat can be extracted in a heat exchanger or solar collector from the endothermic enthalpy of desorption, which is then released as the nanofluid transits through a power generating device such as a turboexpander. Calculations for an R123 MOHC nanofluid indicated potential for up to 15% increase in power output. Capillary tube experiments show that liquid-vapor transitions occur without nanoparticle deposition on the tube walls provided entrance Reynolds number exceeds approximately 100.

  2. Optical heat flux gauge

    DOE Patents [OSTI]

    Noel, B.W.; Borella, H.M.; Cates, M.R.; Turley, W.D.; MacArthur, C.D.; Cala, G.C.

    1991-04-09

    A heat flux gauge is disclosed comprising first and second thermographic phosphor layers separated by a layer of a thermal insulator, wherein each thermographic layer comprises a plurality of respective thermographic sensors in a juxtaposed relationship with respect to each other. The gauge may be mounted on a surface with the first thermographic phosphor in contact with the surface. A light source is directed at the gauge, causing the phosphors to luminesce. The luminescence produced by the phosphors is collected and its spectra analyzed in order to determine the heat flux on the surface. First and second phosphor layers must be different materials to assure that the spectral lines collected will be distinguishable. 9 figures.

  3. Heat transfer probe

    DOE Patents [OSTI]

    Frank, Jeffrey I.; Rosengart, Axel J.; Kasza, Ken; Yu, Wenhua; Chien, Tai-Hsin; Franklin, Jeff

    2006-10-10

    Apparatuses, systems, methods, and computer code for, among other things, monitoring the health of samples such as the brain while providing local cooling or heating. A representative device is a heat transfer probe, which includes an inner channel, a tip, a concentric outer channel, a first temperature sensor, and a second temperature sensor. The inner channel is configured to transport working fluid from an inner inlet to an inner outlet. The tip is configured to receive at least a portion of the working fluid from the inner outlet. The concentric outer channel is configured to transport the working fluid from the inner outlet to an outer outlet. The first temperature sensor is coupled to the tip, and the second temperature sensor spaced apart from the first temperature sensor.

  4. Heat transport system

    DOE Patents [OSTI]

    Harkness, Samuel D.

    1982-01-01

    A falling bed of ceramic particles receives neutron irradiation from a neutron-producing plasma and thereby transports energy as heat from the plasma to a heat exchange location where the ceramic particles are cooled by a gas flow. The cooled ceramic particles are elevated to a location from which they may again pass by gravity through the region where they are exposed to neutron radiation. Ceramic particles of alumina, magnesia, silica and combinations of these materials are contemplated as high-temperature materials that will accept energy from neutron irradiation. Separate containers of material incorporating lithium are exposed to the neutron flux for the breeding of tritium that may subsequently be used in neutron-producing reactions. The falling bed of ceramic particles includes velocity partitioning between compartments near to the neutron-producing plasma and compartments away from the plasma to moderate the maximum temperature in the bed.

  5. Low Cost Polymer heat Exchangers for Condensing Boilers

    SciTech Connect (OSTI)

    Butcher, Thomas; Trojanowski, Rebecca; Wei, George; Worek, Michael

    2015-09-30

    Work in this project sought to develop a suitable design for a low cost, corrosion resistant heat exchanger as part of a high efficiency condensing boiler. Based upon the design parameters and cost analysis several geometries and material options were explored. The project also quantified and demonstrated the durability of the selected polymer/filler composite under expected operating conditions. The core material idea included a polymer matrix with fillers for thermal conductivity improvement. While the work focused on conventional heating oil, this concept could also be applicable to natural gas, low sulfur heating oil, and biodiesel- although these are considered to be less challenging environments. An extruded polymer composite heat exchanger was designed, built, and tested during this project, demonstrating technical feasibility of this corrosion-resistant material approach. In such flue gas-to-air heat exchangers, the controlling resistance to heat transfer is in the gas-side convective layer and not in the tube material. For this reason, the lower thermal conductivity polymer composite heat exchanger can achieve overall heat transfer performance comparable to a metal heat exchanger. However, with the polymer composite, the surface temperature on the gas side will be higher, leading to a lower water vapor condensation rate.

  6. Heat exchanger tube mounts

    DOE Patents [OSTI]

    Wolowodiuk, W.; Anelli, J.; Dawson, B.E.

    1974-01-01

    A heat exchanger in which tubes are secured to a tube sheet by internal bore welding is described. The tubes may be moved into place in preparation for welding with comparatively little trouble. A number of segmented tube support plates are provided which allow a considerable portion of each of the tubes to be moved laterally after the end thereof has been positioned in preparation for internal bore welding to the tube sheet. (auth)

  7. APPARATUS FOR HEATING IONS

    DOE Patents [OSTI]

    Chambers, E.S.; Garren, A.A.; Kippenhan, D.O.; Lamb, W.A.S.; Riddell, R.J. Jr.

    1960-01-01

    The heating of ions in a magnetically confined plasma is accomplished by the application of an azimuthal radiofrequency electric field to the plasma at ion cyclotron resonance. The principal novelty resides in the provision of an output tank coil of a radiofrequency driver to induce the radiofrequency field in the plasma and of electron current bridge means at the ends of the plasma for suppressing radial polarization whereby the radiofrequency energy is transferred to the ions with high efficiency.

  8. SPECIFIC HEAT INDICATOR

    DOE Patents [OSTI]

    Horn, F.L.; Binns, J.E.

    1961-05-01

    Apparatus for continuously and automatically measuring and computing the specific heat of a flowing solution is described. The invention provides for the continuous measurement of all the parameters required for the mathematical solution of this characteristic. The parameters are converted to logarithmic functions which are added and subtracted in accordance with the solution and a null-seeking servo reduces errors due to changing voltage drops to a minimum. Logarithmic potentiometers are utilized in a unique manner to accomplish these results.

  9. Heat transport system

    DOE Patents [OSTI]

    Pierce, Bill L.

    1978-01-01

    A heat transport system of small size which can be operated in any orientation consists of a coolant loop containing a vaporizable liquid as working fluid and includes in series a vaporizer, a condenser and two one-way valves and a pressurizer connected to the loop between the two valves. The pressurizer may be divided into two chambers by a flexible diaphragm, an inert gas in one chamber acting as a pneumatic spring for the system.

  10. Total Space Heat-

    Gasoline and Diesel Fuel Update (EIA)

    Cooling ... 96.7 33.7 8.1 6.6 7.5 20.2 2.9 5.8 1.1 2.4 8.4 Buildings with Water Heating ..... 98.0 34.7 7.8 6.6 8.0 20.1 3.0 5.8 1.1 2.4 8.5 Note: Due to rounding,...

  11. Central Multifamily Water Heating Systems

    Broader source: Energy.gov [DOE]

    The Building America Program is hosting a no-cost, webinar-based training on Central Multifamily Water Heating Systems. The webinar will focus the effective use of central heat pump water heaters...

  12. ARM - Measurement - Sensible heat flux

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    heat flux ARM Data Discovery Browse Data Comments? We would love to hear from you Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Sensible heat flux The time ...

  13. ARM - Measurement - Latent heat flux

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    heat flux ARM Data Discovery Browse Data Comments? We would love to hear from you Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Latent heat flux The time ...

  14. Geothermal Heat Pump Manufacturing Activities

    Gasoline and Diesel Fuel Update (EIA)

    6 Geothermal heat pump-related sales as a percentage of total company sales revenue, 2008 ... U.S. Energy Information Administration (EIA), Form EIA-902, "Annual Geothermal Heat Pump

  15. Industrial Process Heating - Technology Assessment

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Industrial Process Heating - Technology Assessment 1 2 Contents 3 4 1. Introduction to the Technology/System ............................................................................................... 2 5 1.1. Industrial Process Heating Overview ............................................................................................ 2 6 2. Technology Assessment and Potential ................................................................................................. 6 7 2.1. Status

  16. Port Graham Woody Biomass Community Waste Heat Project

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Woody Biomass Community Waste Heat Project Charlie Sink, Chugachmiut For Port Graham Tribal Council U.S. of Energy Tribal Energy Program Annual Tribal Energy Conference 2012 November 13-16, 2012 Nanwalek Nanwalek Port Graham, Alaska Approximately 134 people Annual fuel consumption 53,100 gallons diesel fuel for heat Annual electrical usage 1,340,000 kWh/yr Funding Agencies US Department of Energy Tribal Energy Program (DOE/TEP) http://apps1.eere.energy.gov/tribalenergy/ Alaska Energy Authority

  17. Development of a 75-kW heat-pipe receiver for solar heat-engines

    SciTech Connect (OSTI)

    Adkins, D.R.; Andraka, C.E.; Moss, T.A.

    1995-05-01

    A program is now underway to develop commercial power conversion systems that use parabolic dish mirrors in conjunction with Stirling engines to convert solar energy to electric power. In early prototypes, the solar concentrator focused light directly on the heater tubes of the Stirling engine. Liquid-metal heat-pipes are now being developed to transfer energy from the focus of the solar concentrator to the heater tubes of the engine. The dome-shaped heat-pipe receivers are approximately one-half meters in diameter and up to 77-kW of concentrated solar energy is delivered to the absorber surface. Over the past several years, Sandia National Laboratories, through the sponsorship of the Department of Energy, has conducted a major program to explore receiver designs and identify suitable wick materials. A high-flux bench-scale system has been developed to test candidate wick designs, and full-scale systems have been tested on an 11-meter test-bed solar concentrator. Procedures have also been developed in this program to measure the properties of wick materials, and an extensive data-base on wick materials for high temperature heat pipes has been developed. This paper provides an overview of the receiver development program and results from some of the many heat-pipe tests.

  18. [Waste water heat recovery system

    SciTech Connect (OSTI)

    Not Available

    1993-04-28

    The production capabilities for and field testing of the heat recovery system are described briefly. Drawings are included.

  19. Tubing for augmented heat transfer

    SciTech Connect (OSTI)

    Yampolsky, J.S.; Pavlics, P.

    1983-08-01

    The objectives of the program reported were: to determine the heat transfer and friction characteristics on the outside of spiral fluted tubing in single phase flow of water, and to assess the relative cost of a heat exchanger constructed with spiral fluted tubing with one using conventional smooth tubing. An application is examined where an isolation water/water heat exchanger was used to transfer the heat from a gaseous diffusion plant to an external system for energy recovery. (LEW)

  20. Roadmap for Process Heating Technology

    SciTech Connect (OSTI)

    Eichner, Melissa; Thekdi, Arvind

    2001-03-16

    This roadmap identifies priority research & development goals and near-rerm non- research goals to improve industrial process heating.

  1. Heating Oil and Propane Update

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    Maps of states participating in Winter Fuels Survey Residential propane PADD map Residential heating oil PADD map

  2. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price increases The average retail price for home heating oil rose 6-tenths of a cent from a week ago to $2.18 per gallon. That's down 79 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region are at $2.13 per gallon, unchanged from last week, and down 88

  3. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 1.9 cents from a week ago to $2.16 per gallon. That's down 75 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region are at $2.11 per gallon, down 2.8 cents from last week, and down 77

  4. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 5.1 cents from a week ago to $2.11 per gallon. That's down 72 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region are at $2.05 per gallon, down 5.3 cents from last week, and down 75

  5. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 5 cents from a week ago to $2.06 per gallon. That's down 75 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region are at $2.01 per gallon, down 4.1 cents from last week, and down 78

  6. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 1.8 cents from a week ago to $2.82 per gallon. That's down $1.36 from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $2.79 per gallon, down 1.5 cents from last week, and down $1.34

  7. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price increases The average retail price for home heating oil rose 1.8 cents from a week ago to $2.08 per gallon. That's down 72 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region are at $2.02 per gallon, up 3-tenths of a cent from last week, and down 76

  8. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 1.9 cents from a week ago to $2.80 per gallon. That's down $1.44 from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $2.78 per gallon, down 1.2 cents from last week, and down $1.40

  9. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price increases The average retail price for home heating oil rose 1 cent from a week ago to $2.09 per gallon. That's down 82 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region are at $2.02 per gallon, up 8-tenths of a cent from last week, and down 85

  10. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    Residential heating oil price increases The average retail price for home heating oil rose 1.1 cents from a week ago to $2.10 per gallon. That's down 94 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region are at $2.04 per gallon, up 2.3 cents from last week, and down 95

  11. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    Residential heating oil price decreases The average retail price for home heating oil fell 9-tenths of a cent from a week ago to $2.09 per gallon. That's down $1.09 from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region are at $2.04 per gallon, down 1-tenth of a cent from last week, and down $1.11

  12. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    Residential heating oil price decreases The average retail price for home heating oil fell 5-tenths of a cent from a week ago to $2.09 per gallon. That's down $1.20 from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region are at $2.03 per gallon, down 9-tenths of a cent from last week, and down $1.22

  13. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    Residential heating oil price increases The average retail price for home heating oil rose 6-tenths of a cent from a week ago to $2.10 per gallon. That's down $1.11 from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region are at $2.04 per gallon, up 5-tenths of a cent from last week, and down $1.14

  14. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    Residential heating oil price increases The average retail price for home heating oil rose 2.6 cents from a week ago to $2.12 per gallon. That's down 91 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region are at $2.06 per gallon, up 2.1 cents from last week, and down 94

  15. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    Residential heating oil price increases The average retail price for home heating oil rose 1 cent from a week ago to $2.13 per gallon. That's down 80 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region are at $2.07 per gallon, up 9-tenths of a cent from last week, and down 83

  16. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 10.5 cents from a week ago to $2.93 per gallon, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $2.90 per gallon, down 10.4 cents from last week. This is Marcela Rourk

  17. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 2.3 cents from a week ago to $2.38 per gallon. That's down 99 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $2.32 per gallon, down 3.1 cents from last week, and down $1.00

  18. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 1.5 cents from a week ago to $2.36 per gallon. That's down 97 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $2.31 per gallon, down 2-tenths of a cent from last week, and down 96

  19. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 3 cents from a week ago to $2.33 per gallon. That's down 89 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $2.28 per gallon, down 3.5 cents from last week, and down 9

  20. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 7.6 cents from a week ago to $2.26 per gallon. That's down 89 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $2.19 per gallon, down 8.9 cents from last week, and down 92

  1. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 4.5 cents from a week ago to $2.21 per gallon. That's down 87 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $2.15 per gallon, down 3.6 cents from last week, and down 89

  2. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 3.5 cents from a week ago to $2.18 per gallon. That's down 87 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $2.13 per gallon, down 2.2 cents from last week, and down 88

  3. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    5, 2014 Residential heating oil price decreases The average retail price for home heating oil fell 1.9 cents from a week ago to $3.43 per gallon. That's down 39 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $3.38 per gallon, down 2.6 cents from last week, and down 38.7

  4. Residential heating oil price decreases

    U.S. Energy Information Administration (EIA) Indexed Site

    7, 2014 Residential heating oil price decreases The average retail price for home heating oil fell 7.8 cents from a week ago to $3.14 per gallon. That's down 81.1 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $3.12 per gallon, down 6.5 cents from last week, and down 79.9

  5. Residential heating oil prices available

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil prices available The average retail price for home heating oil is $3.52 per gallon. That's down 32.7 cents from a year ago, based on the U.S. Energy Information Administration's weekly residential heating fuel price survey. Heating oil prices in the New England region are at $3.48 per gallon, down 29.1 cents from a year ago. This is Marcela Rourk, with EIA, in Washington

  6. Residential heating oil prices decline

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 2 cents from a week ago to $3.36 per gallon. That's down 52.5 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $3.31 per gallon, down 1.3 cents from last week, and down 52.6

  7. Residential heating oil prices decline

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil price decreases The average retail price for home heating oil fell 6.3 cents from a week ago to $3.08 per gallon. That's down 90.3 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $3.05 per gallon, down 6.8 cents from last week, and down 91.6

  8. Residential heating oil prices decline

    U.S. Energy Information Administration (EIA) Indexed Site

    2, 2014 Residential heating oil prices decline The average retail price for home heating oil is $3.48 per gallon. That's down 4.5 cents from a week ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region are at $3.43 per gallon, down 5.7 cents from last week. This is Amerine Woodyard

  9. Residential heating oil prices decrease

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil prices decrease The average retail price for home heating oil fell 1.7 cents from a week ago to $4.02 per gallon. That's up 1.7 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to 4.01 per gallon, down 6-tenths of a cent from last week, and up 5.8

  10. Residential heating oil prices decrease

    U.S. Energy Information Administration (EIA) Indexed Site

    9, 2014 Residential heating oil price decreases The average retail price for home heating oil fell 2.9 cents from a week ago to $3.45 per gallon. That's down 36.6 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region fell to $3.41 per gallon, down 3 cents from last week, and down 35

  11. Residential heating oil prices increase

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil prices increase The average retail price for home heating oil rose 5.4 cents from a week ago to $4.04 per gallon. That's up 4.9 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region rose to 4.02 per gallon, up 5.6 cents from last week, and up 8

  12. Residential heating oil prices increase

    U.S. Energy Information Administration (EIA) Indexed Site

    3, 2014 Residential heating oil prices increase The average retail price for home heating oil rose 4.4 cents from a week ago to $4.06 per gallon. That's up 4.1 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region rose to 4.03 per gallon, up 2.5 cents from last week, and up 6

  13. Residential heating oil prices increase

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil prices increase The average retail price for home heating oil rose 12 cents from a week ago to $4.18 per gallon. That's up 13 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region rose to 4.13 per gallon, up 9.8 cents from last week, and up 12.9 cents from a

  14. Residential heating oil prices increase

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil prices increase The average retail price for home heating oil rose 3.9 cents last week to $3.96 per gallon. That's down 2.6 cents from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. The price for heating oil in the New England region averaged 3.92 per gallon, up 5.2 cents from last week, and 1.7

  15. Residential heating oil prices increase

    U.S. Energy Information Administration (EIA) Indexed Site

    heating oil prices increase The average retail price for home heating oil rose 2.9 cents from a week ago to $3.98 per gallon. That's up 6-tenths of a penny from a year ago, based on the residential heating fuel survey by the U.S. Energy Information Administration. Heating oil prices in the New England region rose to 3.96 per gallon, up 4.1 cents from last week, and up 4.8

  16. Characterization of industrial process waste heat and input heat streams

    SciTech Connect (OSTI)

    Wilfert, G.L.; Huber, H.B.; Dodge, R.E.; Garrett-Price, B.A.; Fassbender, L.L.; Griffin, E.A.; Brown, D.R.; Moore, N.L.

    1984-05-01

    The nature and extent of industrial waste heat associated with the manufacturing sector of the US economy are identified. Industry energy information is reviewed and the energy content in waste heat streams emanating from 108 energy-intensive industrial processes is estimated. Generic types of process equipment are identified and the energy content in gaseous, liquid, and steam waste streams emanating from this equipment is evaluated. Matchups between the energy content of waste heat streams and candidate uses are identified. The resultant matrix identifies 256 source/sink (waste heat/candidate input heat) temperature combinations. (MHR)

  17. Heat and mass transfer considerations in advanced heat pump systems

    SciTech Connect (OSTI)

    Panchal, C.B.; Bell, K.J.

    1992-08-01

    Advanced heat-pump cycles are being investigated for various applications. However, the working media and associated thermal design aspects require new concepts for maintaining high thermal effectiveness and phase equilibrium for achieving maximum possible thermodynamic advantages. In the present study, the heat- and mass-transfer processes in two heat-pump systems -- those based on absorption processes, and those using refrigerant mixtures -- are analyzed. The major technical barriers for achieving the ideal performance predicted by thermodynamic analysis are identified. The analysis provides general guidelines for the development of heat- and mass-transfer equipment for advanced heat-pump systems.

  18. Heat and mass transfer considerations in advanced heat pump systems

    SciTech Connect (OSTI)

    Panchal, C.B.; Bell, K.J.

    1992-01-01

    Advanced heat-pump cycles are being investigated for various applications. However, the working media and associated thermal design aspects require new concepts for maintaining high thermal effectiveness and phase equilibrium for achieving maximum possible thermodynamic advantages. In the present study, the heat- and mass-transfer processes in two heat-pump systems -- those based on absorption processes, and those using refrigerant mixtures -- are analyzed. The major technical barriers for achieving the ideal performance predicted by thermodynamic analysis are identified. The analysis provides general guidelines for the development of heat- and mass-transfer equipment for advanced heat-pump systems.

  19. Final Report - National Database of Utility Rates and Rate Structure...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    National Database of Utility Rates and Rate Structure Final Report - National Database of Utility Rates and Rate Structure Awardee: Illinois State University Location: Normal, IL ...

  20. Energy 101: Geothermal Heat Pumps

    ScienceCinema (OSTI)

    None

    2013-05-29

    An energy-efficient heating and cooling alternative, the geothermal heat pump system moves heat from the ground to a building (or from a building to the ground) through a series of flexible pipe "loops" containing water. This edition of Energy 101 explores the benefits Geothermal and the science behind how it all comes together.

  1. DOE - NNSA/NFO -- Rate our Site

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Rate our Site U.S. DOE/NNSA - Nevada Field Office Rate our website The Nevada Field Office is committed to providing high-quality products and services that meet your needs. Your participation in our customer satisfaction survey will help us achieve this goal. NFO would appreciate your taking the time to complete this survey. Responses are confidential. The survey should take approximately 15 minutes or 1 minute per question. You do not have to answers all the questions. How did you feel working

  2. Innovative Miniaturized Heat Pumps for Buildings: Modular Thermal Hub for Building Heating, Cooling and Water Heating

    SciTech Connect (OSTI)

    2010-09-01

    BEETIT Project: Georgia Tech is using innovative components and system design to develop a new type of absorption heat pump. Georgia Tech’s new heat pumps are energy efficient, use refrigerants that do not emit greenhouse gases, and can run on energy from combustion, waste heat, or solar energy. Georgia Tech is leveraging enhancements to heat and mass transfer technology possible in microscale passages and removing hurdles to the use of heat-activated heat pumps that have existed for more than a century. Use of microscale passages allows for miniaturization of systems that can be packed as monolithic full-system packages or discrete, distributed components enabling integration into a variety of residential and commercial buildings. Compared to conventional heat pumps, Georgia Tech’s design innovations will create an absorption heat pump that is much smaller, has higher energy efficiency, and can also be mass produced at a lower cost and assembly time.

  3. Heating Oil Reserve History | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Heating Oil Reserve History Heating Oil Reserve History Creation of an emergency reserve of heating oil was directed by President Clinton on July 10, 2000, when he directed ...

  4. Home Heating Systems | Department of Energy

    Office of Environmental Management (EM)

    separately, many homes use the following approaches: Active Solar Heating Uses the sun to heat either air or liquid and can serve as a supplemental heat source. Electric...

  5. Heat Transfer Laboratory | Argonne National Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Heat Transfer Laboratory Materials in solids or fluid forms play an important role in a ... Argonne's Heat Transfer Laboratory enables researchers to: Synthesize and prepare heat ...

  6. Water Heating Projects | Department of Energy

    Office of Environmental Management (EM)

    HVAC, Water Heating, & Appliances Water Heating Projects Water Heating Projects Figure 1: The system model for the combined Water heater, dehumidifier and cooler (WHDC). A ...

  7. Absorption Heat Pumps | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Heat Pump Systems » Absorption Heat Pumps Absorption Heat Pumps Absorption heat pumps are essentially air-source heat pumps driven not by electricity, but by a heat source such as natural gas, propane, solar-heated water, or geothermal-heated water. Because natural gas is the most common heat source for absorption heat pumps, they are also referred to as gas-fired heat pumps. There are also absorption (or gas-fired) coolers available that work on the same principle. Unlike some absorption heat

  8. Research & Development Roadmap: Emerging Water Heating Technologies...

    Office of Environmental Management (EM)

    Water Heating Technologies Research & Development Roadmap: Emerging Water Heating Technologies The Research and Development (R&D) Roadmap for Emerging Water Heating Technologies ...

  9. Biomass Derivatives Competitive with Heating Oil Costs.

    Energy Savers [EERE]

    Biomass Derivatives Competitive with Heating Oil Costs Transportation fuel Heat or electricity * Data are from literature, except heating oil is adjusted from 2011 winter average * ...

  10. Microsoft Word - Heating Oil Season.docx

    Broader source: Energy.gov (indexed) [DOE]

    4-2015 Heating Oil Season Northeast Home Heating Oil Reserve Trigger Mechanism (Cents per Gallon, Except Where Noted) Week Residential Heating Oil Price Average Brent Spot Price ...

  11. Water Heating Standing Technical Committee Presentation | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Water Heating Standing Technical Committee Presentation Water Heating Standing Technical Committee Presentation This presentation outlines the goals of the Water Heating Standing...

  12. Designs for maximum utilization of district heating systems ...

    Office of Scientific and Technical Information (OSTI)

    AND UTILIZATION; DISTRICT HEATING; DESIGN; ECONOMIC ANALYSIS; GEOTHERMAL DISTRICT HEATING; COST; EFFICIENCY; SENSITIVITY; ECONOMICS; GEOTHERMAL HEATING; HEATING Geothermal ...

  13. Heat Transfer Fluids for Solar Water Heating Systems | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Solar Water Heaters » Heat Transfer Fluids for Solar Water Heating Systems Heat Transfer Fluids for Solar Water Heating Systems Illustration of a solar water heater. Illustration of a solar water heater. Heat-transfer fluids carry heat through solar collectors and a heat exchanger to the heat storage tanks in solar water heating systems. When selecting a heat-transfer fluid, you and your solar heating contractor should consider the following criteria: Coefficient of expansion - the fractional

  14. Improving Entrainment Rate Parameterization

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Entrainment Rate Parameterization For original submission and image(s), see ARM Research Highlights http://www.arm.gov/science/highlights/ Research Highlight Parameterization of entrainment rate is critical for improving representation of cloud- and convection-related processes in climate models; however, much remains unclear. This work seeks to improve understanding and parameterization of entrainment rate by use of aircraft observations and large-eddy simulations of shallow cumulus clouds over

  15. Resonant thermonuclear reaction rate

    SciTech Connect (OSTI)

    Haubold, H.J.; Mathai, A.M.

    1986-08-01

    Basic physical principles for the resonant and nonresonant thermonuclear reaction rates are applied to find their standard representations for nuclear astrophysics. Closed-form representations for the resonant reaction rate are derived in terms of Meijer's G-italic-function. Analytic representations of the resonant and nonresonant nuclear reaction rates are compared and the appearance of Meijer's G-italic-function is discussed in physical terms.

  16. Rate of coal devolatilization in iron and steelmaking processes

    SciTech Connect (OSTI)

    Sampaio, R.S.; Rio Doce, C.V. do; Fruehan, R.J.; Ozturk, B. . Center for Iron and Steel Making Research)

    1991-01-01

    The devolatilization of coal particles under ironmaking and steelmaking conditions was studied. A new experimental technique was developed to measure the rates of devolatilization. A unique method was used to prepare coal particles based on thick coal bands rich in a given maceral group. Experiments with these single particles gave good reproducibility. The rates of devolatilization for all coal types from low to high rank coals were measured in the gaseous atmosphere and within the slag phase. Real time x-ray images were taken for high volatile, low volatile and anthracite coals devolatilizing in a molten smelting slag. The rate in terms of percentage devolatilization were relatively independent of coal type and a small function of furnace temperature at high heating rates and temperatures studied. The rates depended on particle size and heating rates. The results were consistent with internal transport controlled processes primarily heat transfer. Furthermore the rates were the same in the gas and slag phase which is consistent with heat transfer control.

  17. Method of measuring heat influx of a cryogenic transfer system

    DOE Patents [OSTI]

    Niemann, Ralph C.; Zelipsky, Steven A.; Rezmer, Ronald R.; Smelser, Peter

    1981-01-01

    A method is provided for measuring the heat influx of a cryogenic transfer system. A gaseous phase of the cryogen used during normal operation of the system is passed through the system. The gaseous cryogen at the inlet to the system is tempered to duplicate the normal operating temperature of the system inlet. The temperature and mass flow rate of the gaseous cryogen is measured at the outlet of the system, and the heat capacity of the cryogen is determined. The heat influx of the system is then determined from known thermodynamic relationships.

  18. Practical Physiological Monitoring Protocol for Heat Strain Control

    SciTech Connect (OSTI)

    Anderson, R B; Johnson, J S; Burastero, S R; Gilmore, O

    2003-07-01

    This protocol is indicated when employees are: (1) Exposed to Heat Stress above the TLV; (2) Performing low to moderate work rates with rare excursions to heavy rates; NOT for heavy and very heavy work rates or requiring peak outputs for extended periods; and, (3) Determined to need physiological heat strain monitoring by the cognizant Industrial Hygienist. The requirements are: (1) A work/rest regimen must be established at outset and adjusted as needed during operations (see Appendix A); (2) On-going data collection and review; (3) Rest times must be increased if indicated; (4) Intended for normal, healthy adults. Seasonal medical screening is recommended; and (5) Training for affected employees regarding this protocol, hydration, self-limitation, lifestyle effects and signs, symptoms and treatment of heat related illnesses. This protocol is to aid industrial hygienists in assessing individual physiological response to employee heat exposures, and provides guidance to identify and reduce heat strain as needed. Physiological monitoring is recommended when heat exposure exceeds the TLV by {ge} 2 C and/or when evaporative cooling is limited or eliminated. Typically, this occurs when the use of personal protective equipment includes impermeable or water vapor restrictive outer garments. This protocol is used to identify when heat strain may be excessive. This is determined through measurements taken during each rest period. If decision criteria are exceeded, changes in work practices shall be implemented immediately to reduce employee heat strain and prevent heat related illnesses up to and including heat stroke, a life threatening condition. This protocol may not be appropriate under all conditions. Sound Industrial Hygiene professional judgment is required. Because the measurements for this protocol occur during the rest phase of the work/rest regimen, the conditions affecting employee heat strain during the work phase must be carefully weighed. Work rate

  19. Absorption-heat-pump system

    DOE Patents [OSTI]

    Grossman, G.; Perez-Blanco, H.

    1983-06-16

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  20. Waste heat: Utilization and management

    SciTech Connect (OSTI)

    Sengupta, S.; Lee, S.S.

    1983-01-01

    This book is a presentation on waste heat management and utilization. Topics covered include cogeneration, recovery technology, low grade heat recovery, heat dispersion models, and ecological effects. The book focuses on the significant fraction of fuel energy that is rejected and expelled into the environment either as industrial waste or as a byproduct of installation/equipment operation. The feasibility of retrieving this heat and energy is covered, including technical aspects and potential applications. Illustrations demonstrate that recovery methods have become economical due to recent refinements. The book includes theory and practice concerning waste heat management and utilization.