Sample records for approximate heat rates

  1. Inverse bremsstrahlung heating rate in xenon clusters in the eikonal approximation

    SciTech Connect (OSTI)

    Dey, R. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstr. 2, 85748 Garching (Germany); Roy, A. C. [School of Mathematical Sciences, Ramakrishna Mission Vivekananda University, Belur Math, 711202 West Bengal (India)

    2013-03-15T23:59:59.000Z

    We report inverse bremsstrahlung (IB) heating rates in the eikonal approximation (EA). The present analysis is performed using the plasma-screened Rogers and Debye potentials for Xe clusters with two different charge states (6 and 10). We compare the eikonal results with the first Born approximation (FBA) and classical-simulation (CL-sim) (Moll et al., Phys. Plasmas 19, 033303 (2012)) calculations for clusters in infrared light. Calculations have been performed for the field strength of 2.6 Multiplication-Sign 10{sup 8} V/cm. We find that compared to the FBA and CL-sim methods, the IB heating rate in the EA is less sensitive to the choice of the two potentials considered here. The present EA calculation shows that the influence of the inner structure of atomic ion on the heating rate is more prominent for the smaller ion charge (Xe{sup 6+}). In the case of low laser field approximation based on the elastic transport cross sections, it is seen that in contrast to the FBA and classical methods, the heating rate predicted by the EA does not deviate much all over the range of mean kinetic energy of electrons (20-500 eV) considered here for both the charge states of xenon (Xe{sup 6+} and Xe{sup 10+}). Furthermore, for the Rogers potential, EA is found to be in closer agreement with the classical method than the FBA. We also compare the results of the IB heating rate using the present and low-field approximation approaches to the above three methods and observe that the magnitudes of the IB heating rate calculated in the low field approximation are, in general, higher than the corresponding values predicted by the present approach for both the electron-ion potentials.

  2. Combined Retrieval, Microphysical Retrievals and Heating Rates

    SciTech Connect (OSTI)

    Feng, Zhe

    2013-02-22T23:59:59.000Z

    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. Fabrication and heating rate study of microscopic surface electrode ion traps

    E-Print Network [OSTI]

    Daniilidis, N.

    We report heating rate measurements in a microfabricated gold-on-sapphire surface electrode ion trap with a trapping height of approximately 240 ?m. Using the Doppler recooling method, we characterize the trap heating rates ...

  5. Heating Rate Profiles in Galaxy Clusters

    E-Print Network [OSTI]

    Edward C. D. Pope; Georgi Pavlovski; Christian R. Kaiser; Hans Fangohr

    2006-01-05T23:59:59.000Z

    In recent years evidence has accumulated suggesting that the gas in galaxy clusters is heated by non-gravitational processes. Here we calculate the heating rates required to maintain a physically motived mass flow rate, in a sample of seven galaxy clusters. We employ the spectroscopic mass deposition rates as an observational input along with temperature and density data for each cluster. On energetic grounds we find that thermal conduction could provide the necessary heating for A2199, Perseus, A1795 and A478. However, the suppression factor, of the clasical Spitzer value, is a different function of radius for each cluster. Based on the observations of plasma bubbles we also calculate the duty cycles for each AGN, in the absence of thermal conduction, which can provide the required energy input. With the exception of Hydra-A it appears that each of the other AGNs in our sample require duty cycles of roughly $10^{6}-10^{7}$ yrs to provide their steady-state heating requirements. If these duty cycles are unrealistic, this may imply that many galaxy clusters must be heated by very powerful Hydra-A type events interspersed between more frequent smaller-scale outbursts. The suppression factors for the thermal conductivity required for combined heating by AGN and thermal conduction are generally acceptable. However, these suppression factors still require `fine-tuning` of the thermal conductivity as a function of radius. As a consequence of this work we present the AGN duty cycle as a cooling flow diagnostic.

  6. Fabrication and heating rate study of microscopic surface electrode ion traps

    E-Print Network [OSTI]

    N. Daniilidis; S. Narayanan; S. A. Möller; R. Clark; T. E. Lee; P. J. Leek; A. Wallraff; St. Schulz; F. Schmidt-Kaler; H. Häffner

    2010-09-15T23:59:59.000Z

    We report heating rate measurements in a microfabricated gold-on-sapphire surface electrode ion trap with trapping height of approximately 240 micron. Using the Doppler recooling method, we characterize the trap heating rates over an extended region of the trap. The noise spectral density of the trap falls in the range of noise spectra reported in ion traps at room temperature. We find that during the first months of operation the heating rates increase by approximately one order of magnitude. The increase in heating rates is largest in the ion loading region of the trap, providing a strong hint that surface contamination plays a major role for excessive heating rates. We discuss data found in the literature and possible relation of anomalous heating to sources of noise and dissipation in other systems, namely impurity atoms adsorbed on metal surfaces and amorphous dielectrics.

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

    SciTech Connect (OSTI)

    Bacellar, Daniel [University of Maryland, College Park; Ling, Jiazhen [University of Maryland, College Park; Aute, Vikrant [University of Maryland, College Park; Radermacher, Reinhard [University of Maryland, College Park; Abdelaziz, Omar [ORNL

    2014-01-01T23:59:59.000Z

    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.

  8. Approximation Algorithms for Wireless Link Scheduling with Flexible Data Rates

    E-Print Network [OSTI]

    Kesselheim, Thomas

    2012-01-01T23:59:59.000Z

    We consider scheduling problems in wireless networks with respect to flexible data rates. That is, more or less data can be transmitted per time depending on the signal quality, which is determined by the signal-to-interference-plus-noise ratio (SINR). Each wireless link has a utility function mapping SINR values to the respective data rates. We have to decide which transmissions are performed simultaneously and (depending on the problem variant) also which transmission powers are used. In the capacity-maximization problem, one strives to maximize the overall network throughput, i.e., the summed utility of all links. For arbitrary utility functions (not necessarily continuous ones), we present an O(log n)-approximation when having n communication requests. This algorithm is built on a constant-factor approximation for the special case of the respective problem where utility functions only consist of a single step. In other words, each link has an individual threshold and we aim at maximizing the number of lin...

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

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

    Riihimaki, Laura; Shippert, Timothy

    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.

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

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

    Riihimaki, Laura; Shippert, Timothy

    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.

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

    SciTech Connect (OSTI)

    Riihimaki, Laura; Shippert, Timothy

    2014-11-05T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Riihimaki, Laura; Shippert, Timothy

    2014-11-05T23:59:59.000Z

    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.

  13. Heat transfer rates in fixed bed catalytic reactors

    E-Print Network [OSTI]

    Levelton, Bruce Harding

    1951-01-01T23:59:59.000Z

    HEAT TRANSFER RATES IN FIXED BED CATALYTIC REACTORS H EATTRNSFSAIX DB DNCLR YFNOAXa rRJRuSIX nSeR 1951i HssNIJFu FT SI TSBuR FXO LIXSRXS NRLIeeRXOROt HEAT TRANSFER RATES IN FIXED BED CATALYTIC REACTORS H EATTRNSFSAIX BSar DNCLR YFNOAXa r...RJRuSIX June 1951 HEAT TRANSFER RATES IN FIXED BED CATALYTIC REACTORS A Dissertation Submitted to the Faculty of the Agricultural and Mechanical College of Texas in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Major...

  14. Proceedings of the 1992 EPRI heat rate improvement conference

    SciTech Connect (OSTI)

    Henry, R.E. (Sargent and Lundy, Chicago, IL (United States))

    1993-03-01T23:59:59.000Z

    Diverse but compelling forces such as increasing fuel prices, greater power demands, growing competition, and ever more aggressive regulatory incentives are causing utilities to place additional focus on power plant heat rate. The 1992 heat rate improvement conference was a gathering of utility industry experts to share knowledge and concerns on such key issues as on-line measurement of stack gas mass flow rate-increasingly important because of the regulations of the Clean Air Act of 1990. These proceedings present the latest developments by EPRI and the utility industry to improve heat rate. Representatives of utilities, architect/engineering firms, research firms, and manufacturers presented 71 papers, and a panel discussion by the ASME performance test code committee on PTC 46 provided a forum on the overall plant performance test code. These proceedings report on a number of heat rate improvement programs, both in development and in place, including EPRI's Plant Monitoring Workstation (PMW), the State-of-the-Art Power Plant (SOAPP) conceptual design tool, and several developments in boiler performance monitoring, including an on-line system at PEPCO's Morgantown unit 2. Other conference papers describe advances in heat rate improvement through (1) computer software tools modeling boiler cleanliness, heat balance, duct system dynamics, heat rate root cause diagnosis, and conceptual plant design; (2) new instruments and testing systems in the areas of performance testing, heat rate monitoring, circulating water flow measurement, and low-pressure turbine efficiency measurement; and (3) auxiliary equipment improvements such as condensing heat exchangers, macrobiofouling control, condenser in-leakage and air binding control, air heater monitoring, and feedwater heater level control. Individual papers are indexed separately.

  15. Sinc Approximation of the Heat Distribution on the Boundary of a Two-Dimensional Finite Slab

    E-Print Network [OSTI]

    Dinh, Alain Pham Ngoc; Trong, Dang Duc

    2007-01-01T23:59:59.000Z

    We consider the two-dimensional problem of recovering globally in time the heat distribution on the surface of a layer inside of a heat conducting body from two interior temperature measurements. The problem is ill-posed. The approximation function is represented by a two-dimensional Sinc series and the error estimate is given.

  16. Simplified motional heating rate measurements of trapped ions

    E-Print Network [OSTI]

    Epstein, R J; Leibfried, D; Wesenberg, J H; Bollinger, J J; Amini, J M; Blakestad, R B; Britton, J; Home, J P; Itano, W M; Jost, J D; Knill, E; Langer, C; Ozeri, R; Shiga, N; Wineland, D J

    2007-01-01T23:59:59.000Z

    We have measured motional heating rates of trapped atomic ions, a factor that can influence multi-ion quantum logic gate fidelities. Two simplified techniques were developed for this purpose: one relies on Raman sideband detection implemented with a single laser source, while the second is even simpler and is based on time-resolved fluorescence detection during Doppler recooling. We applied these methods to determine heating rates in a microfrabricated surface-electrode trap made of gold on fused quartz, which traps ions 40 microns above its surface. Heating rates obtained from the two techniques were found to be in reasonable agreement. In addition, the trap gives rise to a heating rate of 300 plus or minus 30 per second for a motional frequency of 5.25 MHz, substantially below the trend observed in other traps.

  17. Property:HeatRate | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal PwerPerkins County, Nebraska:PrecourtOid Jump to:DocketFlowGpmGrossGen JumpRating Jump

  18. Cooling rate, heating rate, and aging effects in glassy water Nicolas Giovambattista,1

    E-Print Network [OSTI]

    Sciortino, Francesco

    be glassified by cooling using hyper- quenching techniques (i.e., with rates of the order of 105 K/s [8Cooling rate, heating rate, and aging effects in glassy water Nicolas Giovambattista,1 H. Eugene of water molecules during the process of generating a glass by cooling, and during the process

  19. Standby Rates for Combined Heat and Power Systems

    SciTech Connect (OSTI)

    Sedano, Richard [Regulatory Assistance Partnership; Selecky, James [Brubaker & Associates, Inc.; Iverson, Kathryn [Brubaker & Associates, Inc.; Al-Jabir, Ali [Brubaker & Associates, Inc.

    2014-02-01T23:59:59.000Z

    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.

  20. Resistive Wall Heating of the Undulator in High Repetition Rate

    SciTech Connect (OSTI)

    Qiang, J; Corlett, J; Emma, P; Wu, J

    2012-05-20T23:59:59.000Z

    In next generation high repetition rate FELs, beam energy loss due to resistive wall wakefields will produce significant amount of heat. The heat load for a superconducting undulator (operating at low temperature), must be removed and will be expensive to remove. In this paper, we study this effect in an undulator proposed for a Next Generation Light Source (NGLS) at LBNL. We benchmark our calculations with measurements at the LCLS and carry out detailed parameter studies using beam from a start-to-end simulation. Our preliminarym results suggest that the heat load in the undulator is about 2 W/m or lower with an aperture size of 6 mm for nominal NGLS preliminary design parameters.

  1. Cloud Properties and Radiative Heating Rates for TWP

    SciTech Connect (OSTI)

    Comstock, Jennifer

    2013-11-07T23:59:59.000Z

    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.

  2. 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.

  3. Heat Transfer -1 A satellite in space orbits the sun. The satellite can be approximated as a flat plate with

    E-Print Network [OSTI]

    Virginia Tech

    Heat Transfer - 1 A satellite in space orbits the sun. The satellite can be approximated as a flat plate with dimensions and properties given below. (a) Calculate the solar heat flux (W/m2 is at a distance where the solar heat flux (as defined above) is 500 W/m2 , and the flat plate is oriented

  4. Insensitivity of the rate of ion motional heating to trap-electrode material over a large temperature range

    E-Print Network [OSTI]

    Chiaverini, John

    We present measurements of trapped-ion motional-state heating rates in niobium and gold surface-electrode ion traps over a range of trap-electrode temperatures from approximately 4 K to room temperature (295 K) in a single ...

  5. ELECTRIC CO-HEATING: A METHOD FOR EVALUATING SEASONAL HEATING EFFICIENCIES AND HEAT LOSS RATES IN DWELLINGS

    E-Print Network [OSTI]

    Modera, M.P.

    2012-01-01T23:59:59.000Z

    Effi~ ciency of Fossil~Fired Heating Systems for LabelingInfo. Division, Ext. 6782 Electric Co-heating: A Methodfor Evaluating Seasonal Heating Efficiencies and Heat Loss

  6. 7-111 A Carnot heat engine is used to drive a Carnot refrigerator. The maximum rate of heat removal from the refrigerated space and the total rate of heat rejection to the ambient air are to be determined.

    E-Print Network [OSTI]

    Bahrami, Majid

    7-42 7-111 A Carnot heat engine is used to drive a Carnot refrigerator. The maximum rate of heat removal from the refrigerated space and the total rate of heat rejection to the ambient air are to be determined. Assumptions The heat engine and the refrigerator operate steadily. Analysis (a) The highest

  7. Effect of Heating Rate on Glass Foaming: Transition to Bulk Foam

    SciTech Connect (OSTI)

    Hrma, Pavel R.

    2009-02-15T23:59:59.000Z

    Foaming of glass is an undesirable side effect of glass fining. According to a recent experimental study, the gas-phase volume in the melt heated at a constant rate dramatically increased with an increased rate of heating. This observation indicates that an increased rate of heating (a natural consequence of the increased processing rate experienced as a result of transition to oxy-fuel firing) may exert a substantial influence on glass foaming in advanced glass-melting furnaces. This paper attributes this effect to the change of mode of foam formation in response to an increased rate of heating.

  8. Calculation Methods for the Heat Release Rate of Materials of Unknown Composition 

    E-Print Network [OSTI]

    Biteau, Hubert; Steinhaus, Thomas; Simeoni, Albert; Schemel, Christopher; Marlair, Guy; Bal, Nicolas; Torero, Jose L

    The Heat Release Rate (HRR) is a critical parameter to characterise a fire. Different methods have been developed to estimate it. The most widespread techniques are based on mass balance. If the heat of combustion of the ...

  9. A study of the volatile matter of coal as a function of the heating rate

    SciTech Connect (OSTI)

    Yanes, E.; Wilhite, D.; Riley, J.M. Jr. [Western Kentucky Univ., Bowling Green, KY (United States)] [and others

    1996-12-31T23:59:59.000Z

    A study of the volatile matter yields as a function of the heating rate was conducted. A suite of 21 coal and coke samples varying in rank from anthracitic to lignitic and heating rates from 10{degrees}C/min to about 450{degrees}C/min were used in the study. Heating rates up to 60{degrees}C per minute, which are typically used in ASTM Test Method 5142 (instrumental Proximate Analysis), were achieved in a macro thermogravimetric analysis (TGA) system. Heating rates of 50-200{degrees}C/min were obtained in a micro TGA system. All measurements were made in a nitrogen atmosphere. The results of the study illustrate the dependence of the volatile matter yield on the heating rate. For most coals and cokes the optimum heating rate for determining volatile matter values that agree with those obtained by ASTM Method D 3175 appears to be in the 100-150{degrees}C range.

  10. 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: bjornsson@astro.su.se, E-mail: peter@astro.su.se [Department of Astronomy, AlbaNova University Center, Stockholm University, SE-106 91 Stockholm (Sweden)

    2014-06-01T23:59:59.000Z

    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}.

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

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

    Riihimaki, Laura; Shippert, Timothy

    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.

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

    SciTech Connect (OSTI)

    Riihimaki, Laura; Shippert, Timothy

    2014-11-05T23:59:59.000Z

    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.

  13. Stellar electron-capture rates calculated with the finite-temperature relativistic random-phase approximation

    SciTech Connect (OSTI)

    Niu, Y. F. [State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China); Paar, N.; Vretenar, D. [Physics Department, Faculty of Science, University of Zagreb, Zagreb (Croatia); Meng, J. [School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191 (China); State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China); Department of Physics, University of Stellenbosch, Stellenbosch 7602 (South Africa)

    2011-04-15T23:59:59.000Z

    We introduce a self-consistent microscopic theoretical framework for modeling the process of electron capture on nuclei in stellar environment, based on relativistic energy density functionals. The finite-temperature relativistic mean-field model is used to calculate the single-nucleon basis and the occupation factors in a target nucleus, and J{sup {pi}}=0{sup {+-}}, 1{sup {+-}}, and 2{sup {+-}} charge-exchange transitions are described by the self-consistent finite-temperature relativistic random-phase approximation. Cross sections and rates are calculated for electron capture on {sup 54,56}Fe and {sup 76,78}Ge in stellar environment, and results compared with predictions of similar and complementary model calculations.

  14. On the rate of approximation in finite-alphabet longest increasing subsequence problems

    E-Print Network [OSTI]

    Houdre, Christian; Talata, Zsolt

    2012-09-05T23:59:59.000Z

    =1 ?rB˜r (jr n ) ,(4.4) APPROXIMATION RATE IN LIS PROBLEMS 11 we have for any ? > 0 P(|Ln/ ?pmax ? Jk|> 2?) (4.5) ? P(|Ln ? H˜n,k|> ? ?pmax) + P(|H˜n,k ? ?pmaxJk|> ? ?pmax). Using Lemmas 4.4 and 4.5 below, (4.5) can be upper bounded by 1 + (m? 1)2?2...max 2 ? ?pmax + exp ( ??? ?npmax 16(m? 1) )m?1? r=1 ( 1 + ?r ?n 1? |µr| ) (4.6) + 4(m? 1)n exp ( ??2npmax 8?2max(m? 1)2 ) . Now, from Proposition 3.1, |P(Ln/ ?pmax ? x)? P(Jk ? x)| ? P(|Ln/ ?pmax ? Jk| ? 2?) + P(x? 2?? Jk ? x+2?) ? 1 + (m? 1) 2?2max 2...

  15. Evidence for thermalization of surface-desorbed molecules at heating rates of 108

    E-Print Network [OSTI]

    Zare, Richard N.

    Evidence for thermalization of surface-desorbed molecules at heating rates of 108 K/s C. R of aniline-d7 from a single-crystal surface 0001 of sapphire Al2O3 at a heating rate on the order of 108 K/s was studied using pulsed infrared laser radiation for desorption and resonance enhanced multiphoton ionization

  16. Cloud properties and associated radiative heating rates in the tropical western Pacific

    E-Print Network [OSTI]

    Cloud properties and associated radiative heating rates in the tropical western Pacific James H set of atmospheric remote sensing instruments at sites around the world, including three radiative fluxes and heating rates. Maxima in cloud occurrence are found in the boundary layer and the upper

  17. Semilinear response for the heating rate of cold atoms in vibrating traps

    E-Print Network [OSTI]

    Cohen, Doron

    OFFPRINT Semilinear response for the heating rate of cold atoms in vibrating traps A. Stotland, D;Europhysics Letters (EPL) has a new online home at www.epljournal.org Take a look for the latest journal news.epljournal.org doi: 10.1209/0295-5075/86/10004 Semilinear response for the heating rate of cold atoms in vibrating

  18. Assessment of uncertainty in cloud radiative effects and heating rates through retrieval algorithm differences: Analysis using

    E-Print Network [OSTI]

    Protat, Alain

    Assessment of uncertainty in cloud radiative effects and heating rates through retrieval algorithm. The effect of uncertainty in retrieved quantities on the cloud radiative effect and radiative heating rates translates into sometimes large differences in cloud shortwave radiative effect (CRE) though the majority

  19. High pressure low heat rate phosphoric acid fuel cell stack

    SciTech Connect (OSTI)

    Wertheim, R.J.

    1987-07-07T23:59:59.000Z

    A high pressure phosphoric acid fuel cell stack assembly is described comprising: (a) a stack of fuel cells for producing electricity, the stack including cathode means, anode means, and heat exchange means; (b) means for delivering pressurized air to the cathode means; (c) means for delivering a hydrogen rich fuel gas to the anode means for electrochemically reacting with oxygen in the pressurized air to produce electricity and water; (d) first conduit means connected to the cathode means for exhausting a mixture of oxygen-depleted air and reaction water from the cathode means; (e) second conduit means connected to the first conduit means for delivering a water fog to the first conduit means for entrainment in the mixture of oxygen-depleted air and reaction water to form a two phase coolant having a gaseous air phase and an entrained water droplet phase; (f) means for circulating the coolant to the heat exchange means to cool the stack solely through vaporization of the water droplet phase in the heat exchange means whereby a mixed gas exhaust of air and water vapor is exhausted from the heat exchange means; and (g) means for heating the mixed gas exhaust and delivering the heated mixed gas exhaust at reformer reaction temperatures to an autothermal reformer in the stack assembly for autothermal reaction with a raw fuel to form the hydrogen rich fuel.

  20. Nano-engineering the boiling surface for optimal heat transfer rate and critical heat flux

    E-Print Network [OSTI]

    Phillips, Bren Andrew

    2011-01-01T23:59:59.000Z

    The effects on pool boiling characteristics such as critical heat flux and the heat transfer coefficient of different surface characteristics such as surface wettability, roughness, morphology, and porosity are not well ...

  1. ELECTRIC CO-HEATING: A METHOD FOR EVALUATING SEASONAL HEATING EFFICIENCIES AND HEAT LOSS RATES IN DWELLINGS

    E-Print Network [OSTI]

    Modera, M.P.

    2012-01-01T23:59:59.000Z

    and heating efficiency, inexpensive and practical diagnosti.c techniques are needed, such as pressuriza- tion, infrared

  2. Dependency of Heat Transfer Rate on the Brinkman Number in Microchannels

    E-Print Network [OSTI]

    H. S. Park

    2008-01-07T23:59:59.000Z

    Heat generation from electronics increases with the advent of high-density integrated circuit technology. To come up with the heat generation, microscale cooling has been thought as a promising technology. Prediction of heat transfer rate is crucial in design of microscale cooling device but is not clearly understood yet. This work proposes a new correlation between heat transfer rate and Brinkman number which is nondimensional number of viscosity, flow velocity and temperature. It is expected that the equation proposed by this work can be useful to design microchannel cooling device.

  3. A convex approximation approach to Weighted Sum Rate Maximization of Multiuser MISO Interference Channel under outage constraints

    E-Print Network [OSTI]

    Li, Wei-Chiang; Lin, Che; Chi, Chong-Yung

    2010-01-01T23:59:59.000Z

    This paper considers weighted sum rate maximization of multiuser multiple-input single-output interference channel (MISO-IFC) under outage constraints. The outage-constrained weighted sum rate maximization problem is a nonconvex optimization problem and is difficult to solve. While it is possible to optimally deal with this problem in an exhaustive search manner by finding all the Pareto-optimal rate tuples in the (discretized) outage-constrained achievable rate region, this approach, however, suffers from a prohibitive computational complexity and is feasible only when the number of transmitter-receive pairs is small. In this paper, we propose a convex optimization based approximation method for efficiently handling the outage-constrained weighted sum rate maximization problem. The proposed approximation method consists of solving a sequence of convex optimization problems, and thus can be efficiently implemented by interior-point methods. Simulation results show that the proposed method can yield near-optim...

  4. Multigroup half space moment approximations to the radiative heat transfer equations q

    E-Print Network [OSTI]

    Coudière, Yves

    cooling) over astrophysics to combustion (e.g., in gas turbine combustion chambers). Since radiative heat into direction l 2 ½À1; 1. Furthermore, T ðx; tÞ is the material temperature. The heat conductivity is denoted with the following boundary conditions. For the material temper

  5. JP2.3 CLOUD RADIATIVE HEATING RATE FORCING FROM PROFILES OF RETRIEVED ARCTIC CLOUD MICROPHYSICS

    E-Print Network [OSTI]

    Shupe, Matthew

    JP2.3 CLOUD RADIATIVE HEATING RATE FORCING FROM PROFILES OF RETRIEVED ARCTIC CLOUD MICROPHYSICS surface. In 1997-1998, a large multi-agency effort made the Surface Heat Budget of the Arctic (SHEBA with the ice pack in the Beaufort and Chukchi Seas for one year. Surface-based remote sensors generated

  6. Development of an On-Line Expert System: Heat Rate Degradation Expert System Advisor

    E-Print Network [OSTI]

    Sopocy, D. M.; Henry, R. E.; Gehl, S.; Divakaruni, S. M.

    and performance monitors in evaluating and diagnosing plant performance. Recognizing an industry-wide need for this advanced capability, the Electric Power Research Institute (EPRI) has undertaken the development and demonstration of an on-line expert system... called "Heat Rate Degradation Expert System Advisor." This expert system will enhance the logic trees previously developed and documented in EPRI Report CS-4554, "Heat Rate Improvement Guidelines for Existing Fossil Plants" (1), with analytical...

  7. 7-106 A reversible heat pump is considered. The temperature of the source and the rate of heat transfer to the sink are to be determined.

    E-Print Network [OSTI]

    Bahrami, Majid

    7-39 7-106 A reversible heat pump is considered. The temperature of the source and the rate of heat transfer to the sink are to be determined. Assumptions The heat pump operates steadily. Analysis Combining.5¸ ¹ · ¨ © § ¸ ¸ ¹ · ¨ ¨ © § 1.6 1 1)K300( COP 1 1 maxHP, HL TT Based upon the definition of the heat pump coefficient

  8. Property:Heat Recovery Rating | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal PwerPerkins County, Nebraska:PrecourtOid Jump to:DocketFlowGpmGrossGen JumpRating Jump to:

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

    SciTech Connect (OSTI)

    Mamum, Md Abdullah A. [Old Dominion Univ., Norfolk, VA (United States); Elmustafa, Abdelmageed A, [Old Dominion Univ., Norfolk, VA (United States); Stutzman, Marcy L. [JLAB, Newport News, VA (United States); Adderley, Philip A. [JLAB, Newport News, VA (United States); Poelker, Matthew [JLAB, Newport News, VA (United States)

    2014-03-01T23:59:59.000Z

    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.

  10. Standard Test Method for Measuring Heat Transfer Rate Using a Thin-Skin Calorimeter

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2005-01-01T23:59:59.000Z

    1.1 This test method covers the design and use of a thin metallic calorimeter for measuring heat transfer rate (also called heat flux). Thermocouples are attached to the unexposed surface of the calorimeter. A one-dimensional heat flow analysis is used for calculating the heat transfer rate from the temperature measurements. Applications include aerodynamic heating, laser and radiation power measurements, and fire safety testing. 1.2 Advantages 1.2.1 Simplicity of ConstructionThe calorimeter may be constructed from a number of materials. The size and shape can often be made to match the actual application. Thermocouples may be attached to the metal by spot, electron beam, or laser welding. 1.2.2 Heat transfer rate distributions may be obtained if metals with low thermal conductivity, such as some stainless steels, are used. 1.2.3 The calorimeters can be fabricated with smooth surfaces, without insulators or plugs and the attendant temperature discontinuities, to provide more realistic flow conditions for ...

  11. Proceedings: 2003 EPRI Heat Rate Improvement Conference: January 28-30, 2003, Birmingham, AL

    SciTech Connect (OSTI)

    None

    2003-04-01T23:59:59.000Z

    Every utility strives both to become a low-cost electricity producer and to meet the emission standards set by the Clean Air Act Amendment. In the early round of cost and emission reduction, most utilities opted to blend or switch to lower-cost fuels such as Powder River Basin coal and natural gas. Over the years, EPRI, industry vendors, and the utilities themselves have learned not only to reduce the difficulties encountered with fuel blending and switching, but also to improve plant heat rate with various cost-effective solutions. The 2003 Heat Rate Improvement Conference provided an opportunity for the industry to share its knowledge and experience.

  12. Existing and Past Methods of Test and Rating Standards Related to Integrated Heat Pump Technologies

    SciTech Connect (OSTI)

    Reedy, Wayne R. [Sentech, Inc.

    2010-07-01T23:59:59.000Z

    This report evaluates existing and past US methods of test and rating standards related to electrically operated air, water, and ground source air conditioners and heat pumps, 65,000 Btu/hr and under in capacity, that potentiality incorporate a potable water heating function. Two AHRI (formerly ARI) standards and three DOE waivers were identified as directly related. Six other AHRI standards related to the test and rating of base units were identified as of interest, as they would form the basis of any new comprehensive test procedure. Numerous other AHRI and ASHRAE component test standards were also identified as perhaps being of help in developing a comprehensive test procedure.

  13. Methodology for Calculating Cooling and Heating Energy-Imput-Ratio (EIR) From the Rated Seasonal Performance Efficiency (SEER or HSPF) 

    E-Print Network [OSTI]

    Kim, H.; Baltazar, J. C.; Haberl, J. S.

    2013-01-01T23:59:59.000Z

    This report provides the recommendations to calculate cooling and heating energy-input-ratio (EIR) for DOE-2 simulations excluding indoor fan energy, from the rated cooling and heating seasonal performance efficiency (i.e., ...

  14. Heat-rate improvements obtained by retubing condensers with new, enhanced tube types

    SciTech Connect (OSTI)

    Rabas, T.J. [Argonne National Lab., IL (United States); Taborek, J. [Consulting Services, Virginia Beach, VA (United States)

    1995-01-01T23:59:59.000Z

    Significant fuel savings can be achieved at power plants by retubing the condensers with enhanced tubes. Because of the higher overall heat-transfer coefficient, the exhaust steam is condensed at a lower pressure and the plant efficiency is therefore increased or plant heat rate is reduced. Only the spirally indented type of enhanced tube is currently being used in the U.S. and most other countries; however, different types of enhanced tubes have been proposed for power-plant condensers, each with their own set of attributes. This paper determines what attributes and their magnitudes of enhanced tubes lead to the most energy savings as measured by reduction of the plant heat rate. The particular attributes considered are the inside and outside enhancement levels, the inside efficiency index (inside enhancement level divided by pressure-drop increase), and the enhanced-tube fouling-rate multiplier. Two particular condensers were selected because all necessary information were known from previous heat-rate studies such as the condenser geometry, the circulating-water pump and system information, and the low-pressure turbine characteristics. These are {open_quotes}real-world{close_quotes} condensers and therefore the finding will be representative for many other condenser-retubing applications. However, the authors strongly recommend that an economic evaluation be performed at each site to determine the energy savings and payback time. This generic investigation showed that the outside enhancement level is the most important attribute, and a value of about 1.5 can lead to heat-rate savings of about 20 to 40 Btu/kW-hr. Increasing the inside enhancement is less effective because of the increased pressure drop that leads to a reduction of the coolant flow rate and velocity.

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

    SciTech Connect (OSTI)

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

    2014-07-07T23:59:59.000Z

    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.

  16. RIS-M-2185 CALCULATION OF HEAT RATING AND BURN-UP FOR TEST FUEL PINS

    E-Print Network [OSTI]

    RISØ-M-2185 CALCULATION OF HEAT RATING AND BURN-UP FOR TEST FUEL PINS IRRADIATED IN DR3 C. Bagger of fuel pins irradiated in HP1 rigs. The calculations are carried out rather detailed, especially of the data. INIS Descriptors . BURN-UP, CALORIMETRY, COMPUTER CALCULATIONS, DR-3, FISSION, FUEL ASSEMBLIES

  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)

    2009-06-01T23:59:59.000Z

    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

    2008-01-01T23:59:59.000Z

    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. On-line continuous unit heat rate measurement using EPRI`s plant monitoring workstation

    SciTech Connect (OSTI)

    Levy, E.; Sarunac, N. [Lehigh Univ., Bethlehem, PA (United States); Schnetzler, D. [Potomac Electric Power Company, Newburg, MD (United States)] [and others

    1995-06-01T23:59:59.000Z

    Software for both the Output/Loss and Boiler-Turbine Cycle Efficiency (BTCE) methods for measuring unit heat rate of pulverized coal units is now available with the latest version of EPRI`s Plant Monitoring Workstation (PMW). Both methods are the latest version of EPRI`s Plant Monitoring Workstation (PMW). Both methods are running continuously and on-line at PEPCO`s Morgantown Unit 2. Comparisons have been made between the results generated by the two methods and with measured plant data for parameters such as coal feed rate and stack gas flow rate. This paper reviews the basis of the two measurement methods, explains how they were implemented at Morgantown Unit 2, and gives results showing how the calculated values compare with measurements for a range of unit operating conditions.

  20. Trade-offs between NO{sub x} heat rate and opacity at Morgantown Unit 2

    SciTech Connect (OSTI)

    D`Agostini, M.; Walsh, R.; Eskenazi, D.; Levy, E. [Lehigh Univ., Bethlehem, PA (United States)] [and others

    1996-05-01T23:59:59.000Z

    In work carried out at Morgantown Unit 2, PEPCO and Lehigh University developed techniques for optimizing the operation of an ABB-CE LNCFS III low NO{sub x} firing system. Because of marginal ESP capacity, the ability to reduce NO{sub x} is limited by opacity excursions at this unit. Using a parametric boiler testing approach, and guided by neural network techniques for analysis of the data, control settings were identified which minimize the full load heat rate as a function of the target NO{sub x} level, subject to a stack opacity constraint.

  1. On the approximation of local and linear radiative damping in the middle

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    atmosphere. In general, this damping is a nonlocal process in which heat is transferred to and from remote form 13 November 2009) ABSTRACT The validity of approximating radiative heating rates in the middle'') is investigated. Using radiative heating rate and temperature output from a chemistry­climate model with realistic

  2. Crack growth rates of irradiated austenitic stainless steel weld heat affected zone in BWR environments.

    SciTech Connect (OSTI)

    Chopra, O. K.; Alexandreanu, B.; Gruber, E. E.; Daum, R. S.; Shack, W. J.; Energy Technology

    2006-01-31T23:59:59.000Z

    Austenitic stainless steels (SSs) are used extensively as structural alloys in the internal components of reactor pressure vessels because of their superior fracture toughness. However, exposure to high levels of neutron irradiation for extended periods can exacerbate the corrosion fatigue and stress corrosion cracking (SCC) behavior of these steels by affecting the material microchemistry, material microstructure, and water chemistry. Experimental data are presented on crack growth rates of the heat affected zone (HAZ) in Types 304L and 304 SS weld specimens before and after they were irradiated to a fluence of 5.0 x 10{sup 20} n/cm{sup 2} (E > 1 MeV) ({approx} 0.75 dpa) at {approx}288 C. Crack growth tests were conducted under cycling loading and long hold time trapezoidal loading in simulated boiling water reactor environments on Type 304L SS HAZ of the H5 weld from the Grand Gulf reactor core shroud and on Type 304 SS HAZ of a laboratory-prepared weld. The effects of material composition, irradiation, and water chemistry on growth rates are discussed.

  3. Effects of surface enhancement, film-feed supply rate, and bundle geometry on spray evaporation heat transfer performance

    SciTech Connect (OSTI)

    Moeykens, S.A. [Trane Co., La Crosse, WI (United States); Newton, B.J. [Univ. of Wisconsin, Madison, WI (United States). Mechanical Engineering Dept.; Pate, M.B. [Iowa State Univ., Ames, IA (United States). Mechanical Engineering Dept.

    1995-12-31T23:59:59.000Z

    Testing was conducted with R-134a through an overfeed ratio range of 1.4 to 7.9 in order to evaluate the effects of Reynolds number on shell-side heat transfer performance in the spray evaporation environment. The overfeed ratio is defined as the ratio of the refrigerant flow rate supplied to the tube bundle to the refrigerant flow rate that vaporizes. Data were taken with a fixed refrigerant supply rate while varying the shell-side heat flux from 40 kW/m{sup 2} (12,688 Btu/[h{center_dot}ft{sup 2}]) to 19 kW/m{sup 2} (6,027 Btu/[h{center_dot}ft{sup 2}]). Both triangular and square-pitch tube bundles were tested to determine the effects of bundle geometry on heat transfer performance. Two enhanced condensation surfaces, one enhanced boiling surface, and one low-finned surface tube were used in this study. Plain-surface bundle testing was conducted in parallel with the enhanced surface testing to determine the degree of improvement obtained with the different surface enhancements relative to that of a smooth tube. In addition, the effect of bundle depth on heat transfer performance was evaluated. Refrigerant was introduced into the test section with wide-angle, solid-cone nozzles. To determine the amount of refrigerant contacting the tube bundle, collector testing was performed in parallel with the heat transfer analysis experiments. Using results form the collector tests, bundle overfeed ratios were calculated and are reported. Heat transfer performance showed dependence on film-feed supply rate (i.e., overfeed ratio) to varying degrees, depending on the type of surface enhancement. Those surfaces that limited axial flow of the liquid film yielded poor heat transfer performance in lower rows of the bundle. The spray evaporation heat transfer performance for one of the enhanced condensation surfaces was better than the flooded evaporator performance for the enhanced boiling surface.

  4. Quarterly technical progress report No. 2, December 20-March 19, 1982. Second quarterly report on the effect of rapid heating rate on coal nitrogen and sulfur release

    SciTech Connect (OSTI)

    Gat, N.

    1982-04-26T23:59:59.000Z

    A laser pyrolysis technique is applied to the investigation of the effects of heating rate on release of coal-bound sulfur and nitrogen. An experimental system characterization and calibration has been completed. A detailed documentation was prepared describing the 3-color pyrometer and the data analysis technique. The coal particle feed system has been calibrated to provide accurate mass flow rate at pre-selected particle velocities. The first batch of samples submitted for chemical analysis will be used for the determination of kinetics parameters at a high heating rate (approximately equal to 10/sup 6/ K/s). The coal used presently is a Montana Rosebud. Two other coals are available; one is ILL No. 6 (through EERC) which will need to be pulverized and the second is a Pitt. hv-A (through KVB). It was confirmed that sieve and drag size distribution of coal differ significantly, and that particle shape effects may be significant in the modelling of particle dynamics.

  5. Coal plasticity at high heating rates and temperatures. Final technical progress report

    SciTech Connect (OSTI)

    Gerjarusak, S.; Peters, W.A.; Howard, J.B.

    1995-05-01T23:59:59.000Z

    Plastic coals are important feedstocks in coke manufacture, coal liquefaction, gasification, and combustion. During these processes, the thermoplastic behavior of these coals is also important since it may contribute to desirable or undesirable characteristics. For example, during liquefaction, the plastic behavior is desired since it leads to liquid-liquid reactions which are faster than solid-liquid reactions. During gasification, the elastic behavior is undesired since it leads to caking and agglomeration of coal particles which result in bed bogging in fixed or fluidized bed gasifiers. The plastic behavior of different coals was studied using a fast-response plastometer. A modified plastometer was used to measure the torque required to turn at constant angular speed a cone-shaped disk embedded in a thin layer of coal. The coal particles were packed between two metal plates which are heated electrically. Heating rates, final temperatures, pressures, and durations of experiment ranged from 200--800 K/s, 700--1300 K, vacuum-50 atm helium, and 0--40 s, respectively. The apparent viscosity of the molten coal was calculated from the measured torque using the governing equation of the cone-and-plate viscometer. Using a concentrated suspension model, the molten coal`s apparent viscosity was related to the quantity of the liquid metaplast present during pyrolysis. Seven coals from Argonne National Laboratory Premium Coal Sample Bank were studied. Five bituminous coals, from high-volatile to low-volatile bituminous, were found to have very good plastic behavior. Coal type strongly affects the magnitude and duration of plasticity. Hvb coals were most plastic. Mvb and lvb coals, though the maximum plasticity and plastic period were less. Low rank coals such as subbituminous and lignite did not exhibit any plasticity in the present studies. Coal plasticity is moderately well correlated with simple indices of coal type such as the elemental C,O, and H contents.

  6. Methodology for Calculating Cooling and Heating Energy-Imput-Ratio (EIR) From the Rated Seasonal Performance Efficiency (SEER or HSPF)

    E-Print Network [OSTI]

    Kim, H.; Baltazar, J. C.; Haberl, J. S.

    2013-01-01T23:59:59.000Z

    in the simulations. For a simulation input, a SEER or a HSPF rating needs to be converted to COP95 (i.e., Energy Efficiency Ratio (EER)/3.412) or COP47, respectively, which is the steady-state efficiency at certain test conditions specified in the ANSI.../AHRI Standard 210/240-2008 (AHRI 2008). Issue 2: Fan Energy Removal • The system efficiency ratings currently available (i.e., SEER, EER, or HSPF) are based on net cooling or heating capacity (i.e., total cooling capacity less supply fan heat for cooling...

  7. RATES

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

    Planning & Projects Power Marketing Rates You are here: SN Home page > Power Marketing > RATES Rates and Repayment Services Rates Current Rates FY 15 PRR worksheet (PDF - 31K) FY...

  8. Heat transfer rates for filmwise, dropwise, and superhydrophobic condensation on silicon substrates

    E-Print Network [OSTI]

    Hery, Travis M

    2011-01-01T23:59:59.000Z

    Condensation, a two-phase heat transfer processes, is commonly utilized in industrial systems. Condensation heat transfer can be optimized by using surfaces in which dropwise condensation (DWC) occurs, and even further ...

  9. Approximate Methods for Estimating the Pattern of Nucleotide Substitution and the Variation of Substitution Rates Among Sites

    E-Print Network [OSTI]

    Kumar, Sudhir

    Approximate Methods for Estimating the Pattern of Nucleotide Substitution and the Variation on parsimony and one on pairwise sequence comparison) for estimating the pattern of nucleotide substitution. Introduction Estimation of the pattern of nucleotide substitution, i.e., the relative probabilities

  10. RATES

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

    RATES Rates Document Library SNR Rates Process Calendar (PDF - 171K) Procedures Informal Process Transmission Action Items List (PDF - 144K) Power Action Item List updated on...

  11. A comparison of techniques for on-line monitoring of unit heat rate of coal fired units

    SciTech Connect (OSTI)

    Sarunac, N.; Levy, E. (Lehigh Univ., Bethlehem, PA (USA). Energy Research Center); Williams, S.; Cramer, D. (Potomac Electric Power Co. (US)); Leyse, R. (Electric Power Research Inst., Palo Alto, CA (USA))

    1990-01-01T23:59:59.000Z

    The input/output method is one of the most commonly used approaches for measuring unit performance, but it is rarely used on-line because of difficulties in accurate on-line measurement of coal heating value and flow rate. Two other techniques for monitoring unit heat rate are much more suitable for on-line application. One of these, the boiler turbine cycle efficiency. The output/loss method utilizes information on turbine cycle performance along with measurements of stack gas flow rate, unburned carbon and other commonly available information such as O{sub 2} levels, gas and air temperatures and gross and auxiliary power. This paper provides a summary of the three techniques, describes their characteristics, gives instrumentation requirements and compares accuracies. Guidelines on the applications for which each technique should be considered are also given.

  12. RATES

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

    Marketing > RATES RATES Current Rates Past Rates 2006 2007 2008 2009 2010 2011 2012 Rates Schedules Power CV-F13 CPP-2 Transmissions CV-T3 CV-NWT5 PACI-T3 COTP-T3 CV-TPT7 CV-UUP1...

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

    SciTech Connect (OSTI)

    Hufnagel, Todd C.

    2014-06-09T23:59:59.000Z

    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.

    2004-09-21T23:59:59.000Z

    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. MODEL FOR ALFVEN WAVE TURBULENCE IN SOLAR CORONAL LOOPS: HEATING RATE PROFILES AND TEMPERATURE FLUCTUATIONS

    SciTech Connect (OSTI)

    Asgari-Targhi, M.; Van Ballegooijen, A. A. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street MS-15, Cambridge, MA 02138 (United States)

    2012-02-10T23:59:59.000Z

    It has been suggested that the solar corona may be heated by dissipation of Alfven waves that propagate up from the solar photosphere. According to this theory, counterpropagating Alfven waves are subject to nonlinear interactions that lead to turbulent decay of the waves and heating of the chromospheric and coronal plasma. To test this theory, better models for the dynamics of Alfven waves in coronal loops are required. In this paper, we consider wave heating in an active region observed with the Solar Dynamics Observatory in 2010 May. First a three-dimensional (3D) magnetic model of the region is constructed, and ten magnetic field lines that match observed coronal loops are selected. For each loop we construct a 3D magnetohydrodynamic model of the Alfven waves near the selected field line. The waves are assumed to be generated by footpoint motions inside the kilogauss magnetic flux elements at the two ends of the loop. Based on such models, we predict the spatial and temporal profiles of the heating along the selected loops. We also estimate the temperature fluctuations resulting from such heating. We find that the Alfven wave turbulence model can reproduce the observed characteristics of the hotter loops in the active region core, but the loops at the periphery of the region have large expansion factors and are predicted to be thermally unstable.

  16. Heat Transfer Modeling and Use of Distributed Temperature Measurements to Predict Rate

    E-Print Network [OSTI]

    Hashmi, Gibran Mushtaq

    2014-07-08T23:59:59.000Z

    . .......................................... 53 Figure 21 – Rate simulation for the same case as Fig. 20. ............................................... 54 Figure 22 – Buildup charts for the same case as in Fig. 10. ............................................. 54 Figure 23 – Pareto chart... ................................................................................ 10 CHAPTER III MODEL DEVELOPMENT .................................................................... 12 Introduction .................................................................................................................. 12 Steady...

  17. Particle loading rates for HVAC filters, heat exchangers, and ducts Nomenclature

    E-Print Network [OSTI]

    Siegel, Jeffrey

    particle mass emission rate distribution func- tion for resuspension (mg/lm h) Es particle mass emission The results in this paper suggest important factors that lead to particle deposition on HVAC components

  18. 7-58 A commercial refrigerator with R-134a as the working fluid is considered. The evaporator inlet and exit states are specified. The mass flow rate of the refrigerant and the rate of heat rejected are to be

    E-Print Network [OSTI]

    Bahrami, Majid

    7-22 7-58 A commercial refrigerator with R-134a as the working fluid is considered. The evaporator inlet and exit states are specified. The mass flow rate of the refrigerant and the rate of heat rejected are to be determined. Assumptions 1 The refrigerator operates steadily. 2 The kinetic and potential energy changes

  19. What is Wind Chill Temperature? It is the temperature it "feels like" outside and is based on the rate of heat loss

    E-Print Network [OSTI]

    What is Wind Chill Temperature? It is the temperature it "feels like" outside and is based on the rate of heat loss from exposed skin caused by the effects of wind and cold. As the wind increases, the body is cooled at a faster rate causing the skin temperature to drop. Wind Chill does not impact

  20. Partial fuel stratification to control HCCI heat release rates : fuel composition and other factors affecting pre-ignition reactions of two-stage ignition fuels.

    SciTech Connect (OSTI)

    Dec, John E.; Sjoberg, Carl-Magnus G.; Cannella, William (Chevron USA Inc.); Yang, Yi; Dronniou, Nicolas

    2010-11-01T23:59:59.000Z

    Homogeneous charge compression ignition (HCCI) combustion with fully premixed charge is severely limited at high-load operation due to the rapid pressure-rise rates (PRR) which can lead to engine knock and potential engine damage. Recent studies have shown that two-stage ignition fuels possess a significant potential to reduce the combustion heat release rate, thus enabling higher load without knock.

  1. Fuel-disruption experiments under high-ramp-rate heating conditions. [LMFBR

    SciTech Connect (OSTI)

    Wright, S.A.; Worledge, D.H.; Cano, G.L.; Mast, P.K.; Briscoe, F.

    1983-10-01T23:59:59.000Z

    This topical report presents the preliminary results and analysis of the High Ramp Rate fuel-disruption experiment series. These experiments were performed in the Annular Core Research Reactor at Sandia National Laboratories to investigate the timing and mode of fuel disruption during the prompt-burst phase of a loss-of-flow accident. High-speed cinematography was used to observe the timing and mode of the fuel disruption in a stack of five fuel pellets. Of the four experiments discussed, one used fresh mixed-oxide fuel, and three used irradiated mixed-oxide fuel. Analysis of the experiments indicates that in all cases, the observed disruption occurred well before fuel-vapor pressure was high enough to cause the disruption. The disruption appeared as a rapid spray-like expansion and occurred near the onset of fuel melting in the irradiated-fuel experiments and near the time of complete fuel melting in the fresh-fuel experiment. This early occurrence of fuel disruption is significant because it can potentially lower the work-energy release resulting from a prompt-burst disassembly accident.

  2. Heating, Current Drive, Operations and Diagnostics Issues Understand implications of reduced repetition rate, is it adequate for the

    E-Print Network [OSTI]

    Heating, Current Drive, Operations and Diagnostics Issues Operations · Understand implications of ECRH to improve startup. Heating · ICRF is the base line heating system, compare with NBI and ECRH withstand the anticipated heat loads? Diagnostics · Capability of beam diagnostics for J(r), E(r), etc

  3. Identification of Convection Heat Transfer Coefficient of Secondary Cooling Zone of CCM based on Least Squares Method and Stochastic Approximation Method

    E-Print Network [OSTI]

    Ivanova, Anna

    2010-01-01T23:59:59.000Z

    The detailed mathematical model of heat and mass transfer of steel ingot of curvilinear continuous casting machine is proposed. The process of heat and mass transfer is described by nonlinear partial differential equations of parabolic type. Position of phase boundary is determined by Stefan conditions. The temperature of cooling water in mould channel is described by a special balance equation. Boundary conditions of secondary cooling zone include radiant and convective components of heat exchange and account for the complex mechanism of heat-conducting due to airmist cooling using compressed air and water. Convective heat-transfer coefficient of secondary cooling zone is unknown and considered as distributed parameter. To solve this problem the algorithm of initial adjustment of parameter and the algorithm of operative adjustment are developed.

  4. Sideband cooling an ion to the quantum ground state in a Penning trap with very low heating rate

    E-Print Network [OSTI]

    J. F. Goodwin; G. Stutter; R. C. Thompson; D. M. Segal

    2014-08-23T23:59:59.000Z

    We report the laser cooling of a single $^{40}\\text{Ca}^+$ ion in a Penning trap to the motional ground state in one dimension. Cooling is performed in the strong binding limit on the 729-nm electric quadrupole $S_{1/2}\\leftrightarrow D_{5/2}$ transition, broadened by a quench laser coupling the $D_{5/2}$ and $P_{3/2}$ levels. We find the final phonon number to be $\\bar{n}=0.014\\pm0.009$. We measure the heating rate of the trap to be very low with $\\dot{\\bar{n}}=2.5\\pm 0.3\\textrm{s}^{-1}$ and a scaled spectral noise density of $\\omega S_{E}(\\omega)\\sim1.6^{-8}\\textrm{V}^2\\textrm{m}^{-2}\\textrm{Hz}^{-1}\\textrm{s}^{-1}$, which is consistent with the large ion-electrode distance. We perform Rabi oscillations on the sideband-cooled ion and observe a coherence time of $0.7\\pm 0.1\\textrm{ms}$, noting that the practical performance is currently limited by the intensity noise of the probe laser.

  5. Simplified motional heating rate measurements of trapped ions R. J. Epstein,* S. Seidelin, D. Leibfried, J. H. Wesenberg, J. J. Bollinger, J. M. Amini, R. B. Blakestad, J. Britton,

    E-Print Network [OSTI]

    Simplified motional heating rate measurements of trapped ions R. J. Epstein,* S. Seidelin, D. Leibfried, J. H. Wesenberg, J. J. Bollinger, J. M. Amini, R. B. Blakestad, J. Britton, J. P. Home, W. M have measured motional heating rates of trapped atomic ions, a factor that can influence multi

  6. 11-14 An ideal vapor-compression refrigeration cycle with refrigerant-134a as the working fluid is considered. The rate of heat removal from the refrigerated space, the power input to the compressor, the rate of heat rejection to the environment,

    E-Print Network [OSTI]

    Kostic, Milivoje M.

    to the compressor, the rate of heat rejection to the environment, and the COP are to be determined. Assumptions 1 enters the compressor as a saturated vapor at the evaporator pressure, and leaves the condenser space and the power input to the compressor are determined from s and ( ) ( )( ) ( ) ( )( ) kW1.83 kW7

  7. 7-88 A geothermal power plant uses geothermal liquid water at 160C at a specified rate as the heat source. The actual and maximum possible thermal efficiencies and the rate of heat rejected from this power plant

    E-Print Network [OSTI]

    Bahrami, Majid

    7-31 7-88 A geothermal power plant uses geothermal liquid water at 160ºC at a specified rate and potential energy changes are zero. 3 Steam properties are used for geothermal water. Properties Using saturated liquid properties, the source and the sink state enthalpies of geothermal water are (Table A-4) k

  8. Assessment of Uncertainty in Cloud Radiative Effects and Heating Rates through Retrieval Algorithm Differences: Analysis using 3-years of ARM data at Darwin, Australia

    SciTech Connect (OSTI)

    Comstock, Jennifer M.; Protat, Alain; McFarlane, Sally A.; Delanoe, Julien; Deng, Min

    2013-05-22T23:59:59.000Z

    Ground-based radar and lidar observations obtained at the Department of Energy’s Atmospheric Radiation Measurement Program’s Tropical Western Pacific site located in Darwin, Australia are used to retrieve ice cloud properties in anvil and cirrus clouds. Cloud microphysical properties derived from four different retrieval algorithms (two radar-lidar and two radar only algorithms) are compared by examining mean profiles and probability density functions of effective radius (Re), ice water content (IWC), extinction, ice number concentration, ice crystal fall speed, and vertical air velocity. Retrieval algorithm uncertainty is quantified using radiative flux closure exercises. The effect of uncertainty in retrieved quantities on the cloud radiative effect and radiative heating rates are presented. Our analysis shows that IWC compares well among algorithms, but Re shows significant discrepancies, which is attributed primarily to assumptions of particle shape. Uncertainty in Re and IWC translates into sometimes-large differences in cloud radiative effect (CRE) though the majority of cases have a CRE difference of roughly 10 W m-2 on average. These differences, which we believe are primarily driven by the uncertainty in Re, can cause up to 2 K/day difference in the radiative heating rates between algorithms.

  9. Internal Heat Transfer Coefficient Determination in a Packed Bed From the Transient Response Due to Solid Phase Induction Heating

    E-Print Network [OSTI]

    Geb, David; Zhou, Feng; Catton, Ivan

    2012-01-01T23:59:59.000Z

    to Solid Phase Induction Heating Nonintrusive measurementsgeneration rate via induction heating. The fluid temperaturetechnique, induction heating, bypass effect, channeling

  10. Diplomarbeit Reverse approximation of rate-independent

    E-Print Network [OSTI]

    Sengun, Mehmet Haluk

    -discretizations have been used to construct energetic solutions, but it is also possible to reverse this process zeitdiskreten Gegenstück untersuchen. Solche Zeitdiskretisierungen werden ver- wende

  11. Geothermal heating for Caliente, Nevada

    SciTech Connect (OSTI)

    Wallis, F.; Schaper, J.

    1981-02-01T23:59:59.000Z

    Utilization of geothermal resources in the town of Caliente, Nevada (population 600) has been the objective of two grants. The first grant was awarded to Ferg Wallis, part-owner and operator of the Agua Caliente Trailer Park, to assess the potential of hot geothermal water for heating the 53 trailers in his park. The results from test wells indicate sustainable temperatures of 140/sup 0/ to 160/sup 0/F. Three wells were drilled to supply all 53 trailers with domestic hot water heating, 11 trailers with space heating and hot water for the laundry from the geothermal resource. System payback in terms of energy cost-savings is estimated at less than two years. The second grant was awarded to Grover C. Dils Medical Center in Caliente to drill a geothermal well and pipe the hot water through a heat exchanger to preheat air for space heating. This geothermal preheater served to convert the existing forced air electric furnace to a booster system. It is estimated that the hospital will save an average of $5300 in electric bills per year, at the current rate of $.0275/KWH. This represents a payback of approximately two years. Subsequent studies on the geothermal resource base in Caliente and on the economics of district heating indicate that geothermal may represent the most effective supply of energy for Caliente. Two of these studies are included as appendices.

  12. ARM - Measurement - Radiative heating rate

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDCnarrowband upwellingpolarization ARM Data Discovery

  13. Fast Approximate Convex Decomposition 

    E-Print Network [OSTI]

    Ghosh, Mukulika

    2012-10-19T23:59:59.000Z

    Approximate convex decomposition (ACD) is a technique that partitions an input object into "approximately convex" components. Decomposition into approximately convex pieces is both more efficient to compute than exact ...

  14. Approximate Maximum Principle for Discrete Approximations of ...

    E-Print Network [OSTI]

    2012-03-20T23:59:59.000Z

    Approximations of Optimal Control Systems with. Nonsmooth .... of any endpoint constraints on trajectories of linear one-dimensional control systems in (PN ).

  15. Determination of temperature-dependent heat conductivity and thermal diffusivity of waste glass melter feed

    SciTech Connect (OSTI)

    Pokorny, Richard; Rice, Jarrett A.; Schweiger, Michael J.; Hrma, Pavel R.

    2013-06-01T23:59:59.000Z

    The cold cap is a layer of reacting glass batch floating on the surface of melt in an all-electric continuous glass melter. The heat needed for the conversion of the melter feed to molten glass must be transferred to and through the cold cap. Since the heat flux into the cold cap determines the rate of melting, the heat conductivity is a key property of the reacting feed. We designed an experimental setup consisting of a large cylindrical crucible with an assembly of thermocouples that monitors the evolution of the temperature field while the crucible is heated at a constant rate. Then we used two methods to calculate the heat conductivity and thermal diffusivity of the reacting feed: the approximation of the temperature field by polynomial functions and the finite-volume method coupled with least-squares analysis. Up to 680°C, the heat conductivity of the reacting melter feed was represented by a linear function of temperature.

  16. Geothermal heating

    SciTech Connect (OSTI)

    Aureille, M.

    1982-01-01T23:59:59.000Z

    The aim of the study is to demonstrate the viability of geothermal heating projects in energy and economic terms and to provide nomograms from which an initial estimate may be made without having to use data-processing facilities. The effect of flow rate and temperature of the geothermal water on drilling and on the network, and the effect of climate on the type of housing are considered.

  17. Heat transfer via dropwise condensation on hydrophobic microstructured surfaces

    E-Print Network [OSTI]

    Ruleman, Karlen E. (Karlen Elizabeth)

    2009-01-01T23:59:59.000Z

    Dropwise condensation has the potential to greatly increase heat transfer rates. Heat transfer coefficients by dropwise condensation and film condensation on microstructured silicon chips were compared. Heat transfer ...

  18. TRANSPARENT HEAT MIRRORS FOR PASSIVE SOLAR HEATING APPLICATIONS

    E-Print Network [OSTI]

    Selkowitz, S.

    2011-01-01T23:59:59.000Z

    heating purposes. BACKGROUND The reduction of heat transfer rates by the use of thermal infraredheating applications should become available on the marketplace. Due to their high reflectivity to thermal infrared

  19. Heat-transfer coefficients in agitated vessels. Latent heat models

    SciTech Connect (OSTI)

    Kumpinsky, E. [Ashland Chemical Co., Columbus, OH (United States)] [Ashland Chemical Co., Columbus, OH (United States)

    1996-03-01T23:59:59.000Z

    Latent heat models were developed to calculate heat-transfer coefficients in agitated vessels for two cases: (1) heating with a condensable fluid flowing through coils and jackets; (2) vacuum reflux cooling with an overhead condenser. In either case the mathematical treatment, based on macroscopic balances, requires no iterative schemes. In addition to providing heat-transfer coefficients, the models predict flow rates of service fluid through the coils and jackets, estimate the percentage of heat transfer due to latent heat, and compute reflux rates.

  20. Approximation of Stochastic Process

    E-Print Network [OSTI]

    Alois Pichler

    2012-05-08T23:59:59.000Z

    May 8, 2012 ... The approximation of stochastic processes by trees is an important topic in ... process ? is replaced by a finitely valued stochastic scenario ...

  1. Geothermal heating from Pinkerton Hot Springs at Colorado Timberline Academy, Durango, Colorado. Final technical report

    SciTech Connect (OSTI)

    Allen, C.C.; Allen, R.W.; Beldock, J.

    1981-11-08T23:59:59.000Z

    The efforts to establish a greater pool of knowledge in the field of low temperature heat transfer for the application of geothermal spring waters to space heating are described. A comprehensive set of heat loss experiments involving passive radiant heating panels is conducted and the results presented in an easily interpretable form. Among the conclusions are the facts that heating a 65 to 70 F/sup 0/ space with 90 to 100 F/sup 0/ liquids is a practical aim. The results are compared with the much lower rates published in the American Society of Heating Refrigeration and Air Conditioning Engineers SYSTEMS, 1976. A heat exchange chamber consisting of a 1000 gallon three compartment, insulated and buried tank is constructed and a control and pumping building erected over the tank. The tank is intended to handle the flow of geothermal waters from Pinkerton Hot Springs at 50 GPM prior to the wasting of the spring water at a disposal location. Approximately 375,000 Btu per hour should be available for heating assuming a 15 F/sup 0/ drop in water temperature. A combination of the panel heat loss experiments, construction of the heat exchange devices and ongoing collection of heat loss numbers adds to the knowledge available to engineers in sizing low temperature heat systems, useful in both solar and geothermal applications where source temperature may be often below 110 F/sup 0/.

  2. Heat resistances and thermal acclimation rates in the mosquitofish, Gambusia affinis (Baird and Girard) and the red shiner, Notropis lutrensis (Baird and Girard)

    E-Print Network [OSTI]

    Cox, Myron Isaiah

    1970-01-01T23:59:59.000Z

    , Gambusia ai'finis (Baird and Girard) and the Red Sh', ~Nt 1 1t ' (2 ' d dG d). (Ny1970) Myron I. Cox, B. S. , University of Utah Directed by: Dr. Kirk Strawn Nosquitofish and red shiners were collected from the Little Brazos River and Country Club Lake... CONCLUSIONS. 8 e 22 26 31 31 34 39 4B 59 REI"ERENCES. VITA. 63 LIST OF TABLES Table 1. Analysis of covariance of heat resistances of mosquitofish collected June 28, 1968 from Country Club lake and tested at 40 C ~ Table 2. Analysis of covs...

  3. Determination of Thermal-Degradation Rates of Some Candidate Rankine-Cycle Organic Working Fluids for Conversion of Industrial Waste Heat Into Power 

    E-Print Network [OSTI]

    Jain, M. L.; Demirgian, J.; Krazinski, J. L.; Bushby, H.; Mattes, H.; Purcell, J.

    1984-01-01T23:59:59.000Z

    performance and economic on system performance, reliability, and overall considerations (rate of return on investment economics have impeded widespread development and [ROI]), six organic fluids were identified to deployment of organic Rankine-cycle power... included with the GC unit inte grates the peaks and produc s a report consisting of retention time, peak area, and area percent. The detector's analog output is connected via an A/D converter to a Perkin Elmer (PE) Sigma 15 chromatography data station...

  4. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard (2750-C Segerstrom Ave., Santa Ana, CA 92704)

    1980-01-01T23:59:59.000Z

    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.

  5. Boundary approximate controllability of some linear parabolic April 5, 2013

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Boundary approximate controllability of some linear parabolic systems April 5, 2013 Guillaume Olive controllability of two classes of linear parabolic systems, namely a system of n heat equations coupled through are the only ones concerning the boundary controllability of linear parabolic systems of heat-type. For more

  6. Cluster Heating by Viscous Dissipation of Sound Waves

    E-Print Network [OSTI]

    Mateusz Ruszkowski; Marcus Bruggen; Mitchell C. Begelman

    2004-04-23T23:59:59.000Z

    We simulate the effects of viscous dissipation of waves that are generated by AGN activity in clusters of galaxies. We demonstrate that the amount of viscous heating associated with the dissipation of these waves can offset radiative cooling rates in cooling flow clusters of galaxies. This heating mechanism leads to spatially distributed and approximately symmetrical dissipation. The heating waves reach a given distance from the cluster center on a timescale shorter than the cooling time. This means that this heating mechanism has the potential of quenching cooling flows in a quasi-stable fashion. Moreover, the heating is gentle as no strong shocks are present in the simulations. We first investigated whether a single continuous episode of AGN activity can lead to adequate dissipation to balance cooling rates. These simulations demonstrated that, whereas secondary waves generated by the interaction of the rising bubble with the intracluster medium are clearly present, viscous heating associated with the dissipation of these waves is insufficient to balance radiative cooling. It is only when the central source is intermittent that the viscous dissipation of waves associated with subsequent episodes of activity can offset cooling. This suggests that the ripples observed in the Perseus cluster can be interpreted as being due to the AGN duty cycle, i.e., they trace AGN activity history. The simulations were performed using the PPM adaptive mesh refinement code FLASH in two dimensions.

  7. Modeling of ion heating from viscous damping of reconnection flows in the reversed field pinch

    SciTech Connect (OSTI)

    Svidzinski, V. A.; Fiksel, G.; Mirnov, V. V.; Prager, S. C. [Center for Magnetic Self-Organization in Laboratory and Astrophysical Plasmas and University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

    2008-06-15T23:59:59.000Z

    Strong self-heating of ions is observed in the reversed field pinch (RFP). During a sawtooth crash in the Madison Symmetric Torus RFP, the ion temperature can spontaneously double in {approx}100 {mu}s. It is also observed that high Z impurities are heated more strongly than bulk ions. The possibility of ion heating due to tearing instabilities at sawtooth crash is examined. Heating scenarios due to viscous damping of strongly localized perpendicular and parallel flows driven in the vicinity of resonant surface in tearing mode are considered. Flow amplitudes and spatial scales are estimated from linear and nonlinear resistive magnetohydrodynamic modeling. The heating rates are found from kinetic models with different levels of approximation, up to solving kinetic equation with a Landau collision operator. Results show reasonable agreement of the modeled impurity heating rate with the experiment, while the estimated bulk ions heating is somewhat weaker than in the experiment. Further theoretical and experimental study are required for a more definite conclusion as to whether it is the main ion heating mechanism or if there is some other important ion heating scenario.

  8. Rates & Repayment

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

    Environmental Review-NEPA Financial Data Operations Planning & Projects Power Marketing Rates Rate Adjustments Transmission Ancillary Services Rates WAPA-137 Rate Order Rates and...

  9. Grain growth in a conventional titanium alloy during rapid, continuous heat treatment

    SciTech Connect (OSTI)

    Semiatin, S.L. (Wright Lab., Wright-Patterson AFB, OH (United States)); Soper, J.C. (Wright State Univ., Dayton, OH (United States)); Sukonnik, I.M. (Texas Instruments, Inc., Attleboro, MA (United States))

    1994-04-01T23:59:59.000Z

    The objective of the present work was to analyze the kinetics of beta grain growth during rapid, continuous heating of a conventional alpha-beta titanium alloy. The analysis was based on approximate, closed-form theoretical expressions derived by Bourell and Kaysser and Soper and Semiatin as well as a fully numerical, computer-based approach. The problem and approach discussed here differs from previous investigations of grain growth during continuous heating and cooling, most of which have been for austenite grain growth in the heat-affected zone during welding of steels. In this regard, the main features of the present work are the very high heating rates involved, the avoidance of the application of complex numerical integration schemes, and the avoidance of using isothermal grain growth kinetic data to fit continuous heating results.

  10. Multicriteria approximation through decomposition

    SciTech Connect (OSTI)

    Burch, C. [Carnegie Mellon Univ., Pittsburgh, PA (United States). School of Computer Sciences]|[Sandia National Labs., Albuquerque, NM (United States); Krumke, S. [Univ. of Wuerzburg (Germany). Dept. of Computer Science; Marathe, M. [Los Alamos National Lab., NM (United States); Phillips, C. [Sandia National Labs., Albuquerque, NM (United States). Applied Mathematics Dept.; Sundberg, E. [Rutgers Univ., NJ (United States). Dept. of Computer Science]|[Sandia National Labs., Albuquerque, NM (United States)

    1997-12-01T23:59:59.000Z

    The authors propose a general technique called solution decomposition to devise approximation algorithms with provable performance guarantees. The technique is applicable to a large class of combinatorial optimization problems that can be formulated as integer linear programs. Two key ingredients of the technique involve finding a decomposition of a fractional solution into a convex combination of feasible integral solutions and devising generic approximation algorithms based on calls to such decompositions as oracles. The technique is closely related to randomized rounding. The method yields as corollaries unified solutions to a number of well studied problems and it provides the first approximation algorithms with provable guarantees for a number of new problems. The particular results obtained in this paper include the following: (1) The authors demonstrate how the technique can be used to provide more understanding of previous results and new algorithms for classical problems such as Multicriteria Spanning Trees, and Suitcase Packing. (2) They show how the ideas can be extended to apply to multicriteria optimization problems, in which they wish to minimize a certain objective function subject to one or more budget constraints. As corollaries they obtain first non-trivial multicriteria approximation algorithms for problems including the k-Hurdle and the Network Inhibition problems.

  11. Multicriteria approximation through decomposition

    SciTech Connect (OSTI)

    Burch, C. [Carnegie Mellon Univ., Pittsburgh, PA (United States). School of Computer Science; Krumke, S. [Univ. of Wuerzburg (Germany). Dept. of Computer Science; Marathe, M. [Los Alamos National Lab., NM (United States); Phillips, C. [Sandia National Labs., Albuquerque, NM (United States). Applied Mathematics Dept.; Sundberg, E. [Rutgers Univ., NJ (United States). Dept. of Computer Science

    1998-06-01T23:59:59.000Z

    The authors propose a general technique called solution decomposition to devise approximation algorithms with provable performance guarantees. The technique is applicable to a large class of combinatorial optimization problems that can be formulated as integer linear programs. Two key ingredients of their technique involve finding a decomposition of a fractional solution into a convex combination of feasible integral solutions and devising generic approximation algorithms based on calls to such decompositions as oracles. The technique is closely related to randomized rounding. Their method yields as corollaries unified solutions to a number of well studied problems and it provides the first approximation algorithms with provable guarantees for a number of new problems. The particular results obtained in this paper include the following: (1) the authors demonstrate how the technique can be used to provide more understanding of previous results and new algorithms for classical problems such as Multicriteria Spanning Trees, and Suitcase Packing; (2) they also show how the ideas can be extended to apply to multicriteria optimization problems, in which they wish to minimize a certain objective function subject to one or more budget constraints. As corollaries they obtain first non-trivial multicriteria approximation algorithms for problems including the k-Hurdle and the Network Inhibition problems.

  12. Hybrid Heat Pump Design and Application 

    E-Print Network [OSTI]

    Wagner, J. R.; Koebberman, W. F.

    1985-01-01T23:59:59.000Z

    The Hybrid Heat Pump (HHP) converts industrial waste heat into process steam. Waste heat at temperatures as low as approximately 200°F can be used. Steam output covers a range between 12,000 Ib/h and 50,000 Ib/h, depending on the application...

  13. A convective-radiative heat transfer model for gas core reactors

    SciTech Connect (OSTI)

    Chen, G.; Anghaie, S. [Univ. of Florida, Gainesville, FL (United States)

    1995-12-31T23:59:59.000Z

    A convective-radiative heat transfer model is developed and used to predict the temperature distribution in gaseous fuel nuclear reactor cores. The axisymmetric, thin layer Navier-Stokes equations with diffusive radiation source term are the basis for this modeling approach. An algebraic turbulence model is used to calculate the eddy viscosity. The Rosseland diffusion approximation is used to model the radiative heat transfer. A hybrid implicit-explicit numerical scheme with Gauss-Seidel iterative process and a highly stretched grid system near wall is employed to solve the governing equations. Several cases with different internal heat generation rates are modeled and analyzed. Results of the temperature distribution, wall heat flux and the associated Nusselt number are presented. The influence of the internal heat generation rate and the wall temperature on the radiative and convective wall heat fluxes are discussed. At gas and wall temperatures close to 3,500 K and 1,600 K, respectively, the radiative and convective heat transfer rates have similar values.

  14. Convective heat-transfer predictions and experiments in an IC engine

    SciTech Connect (OSTI)

    Yang, J.

    1988-01-01T23:59:59.000Z

    Knowledge of heat transfer in engines is critical to engine efficiency, hydrocarbon and particulate emissions, engine-component thermal stress analysis, as well as engine cycle simulation accuracy. However, the relationship between pressure, heat-release rate, turbulent flow, and the heat transfer is not known. Previous engine heat-transfer models, including the law-of-the-wall used for multi-dimensional calculations, are based on a steady-state incompressible flow which is not the case in engines. A new heat-transfer model was developed which is based on an approximate solution of the linearized and normalized one-dimensional energy equation. An empirical turbulent viscosity relation has been used to include the effects of turbulence. The response of this equation to a unit step function was acquired by multi-parameter fit to the numerical solution. The effects of initial thermal boundary layer formed before compression were also considered. The proposed heat-transfer model was extended to include the effects of combustion. Thus, the relationship between pressure variation, spatially-resolved heat-release rate, local flow condition, initial thermal boundary layer, and the surface heat flux and temperature profile was developed.

  15. Polynomial Approximations for Continuous Linear Programs

    E-Print Network [OSTI]

    2012-04-05T23:59:59.000Z

    where the cost rate c(t), the right hand side vector b(t) as well as the matrices. G(t) and H(t, ... dual approximations, respectively, estimates the degree of suboptimality of the ...... the matrix of capital coefficients, where Bij defines the stock of good i required per unit of ...... In Optimization methods for resource allocation (Proc.

  16. Approximate Primal Solutions and Rate Analysis for Dual ...

    E-Print Network [OSTI]

    2007-03-29T23:59:59.000Z

    Mar 28, 2007 ... grams with application to multicommodity network flows, ... [15] S. Low and D.E. Lapsley, Optimization flow control, I: Basic algorithm and con-.

  17. 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...

  18. 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...

  19. 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...

  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)

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

  2. Heat release rate markers for premixed combustion

    E-Print Network [OSTI]

    Nikolaou, Zacharias M.; Swaminathan, Nedunchezhian

    2014-06-16T23:59:59.000Z

    of CO, H2, H2O, CO2 and CH4 and the mole fraction percentages of these species are given in Table 1. This composition is typical of a BFG mixture [18], or a low hydrogen content syngas mixture [21–23]. At these conditions the laminar flame speed is sl... -based correlation and propose new correlations, if required, for a syngas containing multiple fuel species and other species, specifically CO, H2, CH4, H2O and CO2 in a proportion akin to Blast Furnace Gas (BFG). Although this gas has low calorific value, its use...

  3. The Broadband Heating Rate Profile (BBHRP) VAP

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our InstagramStructureProposedPAGESafetyTed5, 2015 IndependentThe

  4. Application Study of a Single House Horizontal Heating System

    E-Print Network [OSTI]

    Hang, Y.; Ying, D.

    2006-01-01T23:59:59.000Z

    It is imperative to get new heating systems into the market and implement rate structures with heat meters for the purpose of energy conservation and environmental protection. Based on analysis of current heating technology, this paper analyzes...

  5. Demonstration, testing, and evaluation of in situ heating of soil. Volume 1, Final report

    SciTech Connect (OSTI)

    Dev, H.; Enk, J.; Jones, D.; Sabato, W.

    1996-04-05T23:59:59.000Z

    This document is a final reports in two volumes. Volume I contains the technical report and Volume II contains appendices with background information and data. In this project approximately 300 cubic yards of clayey soil containing a low concentration plume of volatile organic chemicals was heated in situ by the application of electrical energy. It was shown that as a result of heating the effective permeability of soil to air flow was increased such that in situ soil vapor extraction could be performed. The initial permeability of soil was so low that the soil gas flow rate was immeasurably small even at high vacuum levels. It was demonstrated that the mass flow rate of the volatile organic chemicals was enhanced in the recovered soil gas as a result of heating.

  6. The flow and heat transfer in a viscous fluid over an unsteady stretching surface

    E-Print Network [OSTI]

    Ene, Remus-Daniel; Marinca, Bogdan

    2015-01-01T23:59:59.000Z

    In this paper we have studied the flow and heat transfer in a viscous fluid by a horizontal sheet. The stretching rate and temperature of the sheet vary with time. The governing equations for momentum and thermal energy are reduced to ordinary differential equations by means of similarity transformation. These equations are solved approximately by means of the Optimal Homotopy Asymptotic Method (OHAM) which provides us with a convenient way to control the convergence of approximation solutions and adjust convergence rigorous when necessary. Some examples are given and the results obtained reveal that the proposed method is effective and easy to use.

  7. Uniform asymptotic approximations of integrals 

    E-Print Network [OSTI]

    Khwaja, Sarah Farid

    2014-07-01T23:59:59.000Z

    In this thesis uniform asymptotic approximations of integrals are discussed. In order to derive these approximations, two well-known methods are used i.e., the saddle point method and the Bleistein method. To start with ...

  8. Heating system

    SciTech Connect (OSTI)

    Nishman, P.J.

    1983-03-08T23:59:59.000Z

    A heating system utilizing solar panels and buried ground conduits to collect and store heat which is delivered to a heatpump heat exchanger. A heat-distribution fluid continuously circulates through a ground circuit to transfer heat from the ground to the heat exchanger. The ground circuit includes a length of buried ground conduit, a pump, a check valve and the heat exchanger. A solar circuit, including a solar panel and a second pump, is connected in parallel with the check valve so that the distribution fluid transfers solar heat to the heat exchanger for utilization and to the ground conduit for storage when the second pump is energized. A thermostatically instrumented control system energizes the second pump only when the temperature differential between the solar panel inlet and outlet temperatures exceeds a predetermined value and the ground temperature is less than a predetermined value. Consequently, the distribution fluid flows through the solar panel only when the panel is capable of supplying significant heat to the remainder of the system without causing excessive drying of the ground.

  9. The Temperature of Interstellar Clouds from Turbulent Heating

    E-Print Network [OSTI]

    Liubin Pan; Paolo Padoan

    2008-10-22T23:59:59.000Z

    To evaluate the effect of turbulent heating in the thermal balance of interstellar clouds, we develop an extension of the log-Poisson intermittency model to supersonic turbulence. The model depends on a parameter, d, interpreted as the dimension of the most dissipative structures. By comparing the model with the probability distribution of the turbulent dissipation rate in a simulation of supersonic and super-Alfvenic turbulence, we find a best-fit value of d=1.64. We apply this intermittency model to the computation of the mass-weighted probability distribution of the gas temperature of molecular clouds, high-mass star-forming cores, and cold diffuse HI clouds. Our main results are: i) The mean gas temperature in molecular clouds can be explained as the effect of turbulent heating alone, while cosmic ray heating may dominate only in regions where the turbulent heating is low; ii) The mean gas temperature in high-mass star-forming cores with typical FWHM of ~6 km/s (corresponding to a 1D rms velocity of 2.5 km/s) may be completely controlled by turbulent heating, which predicts a mean value of approximately 36 K, two to three times larger than the mean gas temperature in the absence of turbulent heating; iii) The intermittency of the turbulent heating can generate enough hot regions in cold diffuse HI clouds to explain the observed CH+ abundance, if the rms velocity on a scale of 1 pc is at least 3 km/s, in agreement with previous results based on incompressible turbulence. Because of its importance in the thermal balance of molecular clouds and high-mass star-forming cores, the process of turbulent heating may be central in setting the characteristic stellar mass and in regulating molecular chemical reactions.

  10. Feedstock blending studies with laboratory indirectly heated gasifiers

    SciTech Connect (OSTI)

    Green, A.E.S.; Mullin, J.P.

    1999-10-01T23:59:59.000Z

    To support the further development of indirectly heated gasifiers intended to provide fuels for advanced gas turbines, several indirectly heated laboratory gasifiers were constructed. During many comparative tests, advantages and problems with each system were observed. The most useful systems make use of laboratory tube furnaces in conjunction with temperature, time and pressure or volume yield measuring systems and a gas chromatograph with a thermal conductivity detector. In this paper, high temperature pyrolysis results obtained with the latest system are presented. Contrasting feedstocks suitable for commercial systems separately or in blends are used. Yield versus time measurements are used to determine relevant rate constants and outputs. Since the rate constants are mainly reflective of heat transfer effects, cylindrical dowel sticks of varying radii were volatilized. The data set leads to an analytic heat transfer model that considers the hemicellulose, cellulose, and lignin components of the dowels. Also developed from the dowel experiments is an approximate procedure for estimating the proportionate releases of CO, CO{sub 2}, CH{sub 4}, and H{sub 2} for any type of biomass whose component proportions are known.

  11. Cooperative heat transfer and ground coupled storage system

    DOE Patents [OSTI]

    Metz, Philip D. (Rocky Point, NY)

    1982-01-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Fortini, O.M.; Fruehan, R.J. [US Steel Research & Technological Center, Monroeville, PA (United States)

    2005-12-01T23:59:59.000Z

    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.

  13. Heat Transfer of a Multiple Helical Coil Heat Exchanger Using a Microencapsulated Phase Change Material Slurry 

    E-Print Network [OSTI]

    Gaskill, Travis

    2012-02-14T23:59:59.000Z

    The present study has focused on the use of coil heat exchangers (CHEs) with microencapsulated phase change material (MPCM) slurries to understand if CHEs can yield greater rates of heat transfer. An experimental study was conducted using a...

  14. Heat Transfer of a Multiple Helical Coil Heat Exchanger Using a Microencapsulated Phase Change Material Slurry

    E-Print Network [OSTI]

    Gaskill, Travis

    2012-02-14T23:59:59.000Z

    The present study has focused on the use of coil heat exchangers (CHEs) with microencapsulated phase change material (MPCM) slurries to understand if CHEs can yield greater rates of heat transfer. An experimental study was conducted using a...

  15. Acoustically enhanced heat exchange and drying apparatus

    DOE Patents [OSTI]

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

    1987-07-10T23:59:59.000Z

    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.

  16. Calorimetric measurements of nuclear heating in small probes of plasma-facing materials

    SciTech Connect (OSTI)

    Kumar, A.; Abdou, M.A.; Youssef, M.Z. [Univ. of California, Los Angeles, CA (United States)] [and others

    1994-12-31T23:59:59.000Z

    Direct measurements of nuclear heating in small probes of materials subjected to D-T neutrons from an accelerator based source were initiated during 1989 under USDOE/JAERI collaborative program. A calorimetric technique was utilized to make these measurements. The probes of plasma facing materials, among others, were kept very close, {approximately}3 to {approximately}7 cm, to the neutron source inside an evacuated vacuum chamber. A typical probe measured 20 mm in diameter by 20 mm in length. Typical source intensity was {approximately}2 x 10{sup 12} n/s. The temperature changes in the probe medium were detected by thermal sensors spatially distributed in the probe. The thermal sensors included bead-thermistors, and platinum RTD`s. The change in resistance of a thermal sensor due to onset of nuclear heating was picked up by an automated data acquisition and control system that included a highly sensitive digital voltmeter that had a resolution of 100 nV in voltage range of 300 mV or less. Usually, an individual probe was subjected to spaced neutron pulses of time duration 3 m to 10 m. Two consecutive source neutron pulses were separated by a cooling interval of almost the same duration as that of a source pulse. This approach made it possible to clearly distinguish between the heating and drift phases of the probe medium, on one hand, and to ascertain and verify the reproducibility of measured heating rates from one neutron pulse to another, on the other hand.

  17. Supporting Text Approximation of the Multinomial. Using Stirling's approximation

    E-Print Network [OSTI]

    Peterson, Carsten

    Supporting Text Approximation of the Multinomial. Using Stirling's approximation n! (n/e)n 2n! . [S12] To calculate B L (^n) limN BN L (^n), we apply Stirling's formula to N!, n0!, and n1!, which that r Stirling's formula

  18. 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...

  19. Corrosive resistant heat exchanger

    DOE Patents [OSTI]

    Richlen, Scott L. (Annandale, VA)

    1989-01-01T23:59:59.000Z

    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.

  20. Heat collector

    DOE Patents [OSTI]

    Merrigan, Michael A. (Santa Cruz, NM)

    1984-01-01T23:59:59.000Z

    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.

  1. Heat collector

    DOE Patents [OSTI]

    Merrigan, M.A.

    1981-06-29T23:59:59.000Z

    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.

  2. AGN Heating through Cavities and Shocks

    E-Print Network [OSTI]

    P. E. J. Nulsen; C. Jones; W. R. Forman; L. P. David; B. R. McNamara; D. A. Rafferty; L. Birzan; M. W. Wise

    2006-11-04T23:59:59.000Z

    Three comments are made on AGN heating of cooling flows. A simple physical argument is used to show that the enthalpy of a buoyant radio lobe is converted to heat in its wake. Thus, a significant part of ``cavity'' enthalpy is likely to end up as heat. Second, the properties of the repeated weak shocks in M87 are used to argue that they can plausibly prevent gas close to the AGN from cooling. As the most significant heating mechanism at work closest to the AGN, shock heating probably plays a critical role in the feedback mechanism. Third, results are presented from a survey of AGN heating rates in nearby giant elliptical galaxies. With inactive systems included, the overall AGN heating rate is reasonably well matched to the total cooling rate for the sample. Thus, intermittent AGN outbursts are energetically capable of preventing the hot atmospheres of these galaxies from cooling and forming stars.

  3. Determination of heat conductivity and thermal diffusivity of waste glass melter feed: Extension to high temperatures

    SciTech Connect (OSTI)

    Rice, Jarrett A. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Pokorny, Richard [Inst. of Chemical Technology, Prague (Czech Republic); Schweiger, Michael J. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Hrma, Pavel R. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Pohang Univ. of Science and Technology (Korea, Republic of)

    2014-06-01T23:59:59.000Z

    The heat conductivity ({lambda}) and the thermal diffusivity (a) of reacting glass batch, or melter feed, control the heat flux into and within the cold cap, a layer of reacting material floating on the pool of molten glass in an all-electric continuous waste glass melter. After previously estimating {lambda} of melter feed at temperatures up to 680 deg C, we focus in this work on the {lambda}(T) function at T > 680 deg C, at which the feed material becomes foamy. We used a customized experimental setup consisting of a large cylindrical crucible with an assembly of thermocouples, which monitored the evolution of the temperature field while the crucible with feed was heated at a constant rate from room temperature up to 1100°C. Approximating measured temperature profiles by polynomial functions, we used the heat transfer equation to estimate the {lambda}(T) approximation function, which we subsequently optimized using the finite-volume method combined with least-squares analysis. The heat conductivity increased as the temperature increased until the feed began to expand into foam, at which point the conductivity dropped. It began to increase again as the foam turned into a bubble-free glass melt. We discuss the implications of this behavior for the mathematical modeling of the cold cap.

  4. Heat exchanger for power generation equipment

    DOE Patents [OSTI]

    Nirmalan, Nirm Velumylm; Bowman, Michael John

    2005-06-14T23:59:59.000Z

    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.

  5. Coal home heating and environmental tobacco smoke in relation to lower respiratory illness in Czech children, from birth to 3 years of age

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    still com- monly used in home heating and smoking rates arefound exposure to coal home heating and ETS increase youngcigarette smoke, coal heating, and respiratory symptoms of

  6. Heating System Specification Specification of Heating System

    E-Print Network [OSTI]

    Day, Nancy

    Appendix A Heating System Specification /* Specification of Heating System (loosely based */ requestHeat : Room ­? bool; 306 #12; APPENDIX A. HEATING SYSTEM SPECIFICATION 307 /* user inputs */ livingPattern : Room ­? behaviour; setTemp : Room ­? num; heatSwitchOn, heatSwitchOff, userReset : simple

  7. Heat exchanger containing a component capable of discontinuous movement

    DOE Patents [OSTI]

    Wilson, David Gordon

    2001-04-17T23:59:59.000Z

    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.

  8. Heat exchanger containing a component capable of discontinuous movement

    DOE Patents [OSTI]

    Wilson, David Gordon (Winchester, MA)

    2002-01-01T23:59:59.000Z

    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.

  9. Heat exchanger containing a component capable of discontinuous movement

    DOE Patents [OSTI]

    Wilson, David G. (Winchester, MA)

    1993-01-01T23:59:59.000Z

    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.

  10. Near-field heat transfer between a nanoparticle and a rough surface

    E-Print Network [OSTI]

    Svend-Age Biehs; Jean-Jacques Greffet

    2011-03-11T23:59:59.000Z

    In this work we focus on the surface roughness correction to the near-field radiative heat transfer between a nanoparticle and a material with a rough surface utilizing a direct perturbation theory up to second order in the surface profile. We discuss the different distance regimes for the local density of states above the rough material and the heat flux analytically and numerically. We show that the heat transfer rate is larger than that corresponding to a flat surface at short distances. At larger distances it can become smaller due to surface polariton scattering by the rough surface. For distances much smaller than the correlation length of the surface profile, we show that the results converge to a proximity approximation, whereas in the opposite limit the rough surface can be replaced by an equivalent surface layer.

  11. Mechanism design with approximate types

    E-Print Network [OSTI]

    Zhu, Zeyuan Allen

    2012-01-01T23:59:59.000Z

    In mechanism design, we replace the strong assumption that each player knows his own payoff type exactly with the more realistic assumption that he knows it only approximately: each player i only knows that his true type ...

  12. Transient approximations in queueing networks

    E-Print Network [OSTI]

    Andrewartha, John Michael

    1989-01-01T23:59:59.000Z

    TRANSIENT APPROXIMATIONS IN QUEUEING NETWORKS A Thesis by JOHN MICHAEL ANDREWARTHA Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1989... Major Subject: Electrical Engineering TRANSIENT APPROXIMATIONS IN QUEUEING NETWORKS A Thesis JOHN MICHAEL ANDREWARTHA Approved as to style and content by: P. E. Cantrell (Chair of Committee) m P7~ W. K. Tsai (Member) J. D. Gibson (Member) R...

  13. E-Print Network 3.0 - area blockage rate Sample Search Results

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

    of increase of the differential pressure across the generating bank is correlated... the heat transfer impact of fouling is an important issue, heat transfer rates are easily...

  14. Proceedings of HT'03 2003 Summer Heat Transfer Conference

    E-Print Network [OSTI]

    Walker, D. Greg

    Proceedings of HT'03 2003 Summer Heat Transfer Conference July 21­23, 2003, Las Vegas, Nevada, USA HT2003-47016 A NEW TECHNIQUE FOR HEAT FLUX DETERMINATION D.G. Walker Department of Mechanical@vt.edu ABSTRACT A new method for estimating heat fluxes from heating rate measurements and an approach to measure

  15. Original article Heat balance of a multistage spray-dryer

    E-Print Network [OSTI]

    Boyer, Edmond

    into account. From these data, the heat balance showed a dif- ference between inputs and outputs of 2.9% which may be interpreted as heat losses and probable errors. The specific heat consumption was close to 4 of the small flow rates of air used in both fluid beds. This specific heat consumption corresponds to 2.1 times

  16. NBSBR 84-2867 Test Procedures for Rating

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    NBSBR 84-2867 Test Procedures for Rating Residential Heating and Cooling Absorption Equipment U the heating mode. Both air-source and ground water source absorption heat pumps are considered, as well as air for estimating the heating and cooling seasonal performance and cost of operation of residential water chillers

  17. Efficiency Ratings for the Daiken AC (Americas), Inc.

    E-Print Network [OSTI]

    Efficiency Ratings for the Daiken AC (Americas), Inc. Altherma Air-to-Water Source Heat Pump System is used to provide water heating, the EF for that separate water heater shall be used for performance Description Model No. Capacity (tons) Space Heating Space Cooling SEER Water Heating Efficiency

  18. Approximate model checking of stochastic hybrid systems , J.-P. Katoen

    E-Print Network [OSTI]

    Abate, Alessandro

    -room heating system. 1 Introduction Stochastic hybrid systems are a broad and widely applicable classApproximate model checking of stochastic hybrid systems A. Abate , J.-P. Katoen , J. Lygeros , and M. Prandini§ Abstract A method for approximate model checking of stochastic hybrid systems

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

    SciTech Connect (OSTI)

    Abdelaziz, Omar [ORNL] [ORNL; Shrestha, Som S [ORNL] [ORNL

    2014-01-01T23:59:59.000Z

    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%.

  20. Shock-Wave Heating Model for Chondrule Formation: Prevention of Isotopic Fractionation

    E-Print Network [OSTI]

    Hitoshi Miura; Taishi Nakamoto

    2006-07-03T23:59:59.000Z

    Chondrules are considered to have much information on dust particles and processes in the solar nebula. It is naturally expected that protoplanetary disks observed in present star forming regions have similar dust particles and processes, so study of chondrule formation may provide us great information on the formation of the planetary systems. Evaporation during chondrule melting may have resulted in depletion of volatile elements in chondrules. However, no evidence for a large degree of heavy-isotope enrichment has been reported in chondrules. In order to meet this observed constraint, the rapid heating rate at temperatures below the silicate solidus is required to suppress the isotopic fractionation. We have developed a new shock-wave heating model taking into account the radiative transfer of the dust thermal continuum emission and the line emission of gas molecules and calculated the thermal history of chondrules. We have found that optically-thin shock waves for the thermal continuum emission from dust particles can meet the rapid heating constraint, because the dust thermal emission does not keep the dust particles high temperature for a long time in the pre-shock region and dust particles are abruptly heated by the gas drag heating in the post-shock region. We have also derived the upper limit of optical depth of the pre-shock region using the radiative diffusion approximation, above which the rapid heating constraint is not satisfied. It is about 1 - 10.

  1. Radiation Pressure Supported AGN Tori with Hard X-Ray and Stellar Heating

    E-Print Network [OSTI]

    Jiming Shi; Julian H. Krolik

    2008-02-13T23:59:59.000Z

    The dynamics and structure of toroidal obscuration around AGN remain uncertain and controversial. In this paper we extend earlier work on the dynamical role of infrared radiation pressure by adding the effects of two kinds of distributed heating: Compton-heating due to hard X-rays from the nucleus and local starlight heating. We find numerical solutions to the axisymmetric hydrostatic equilibrium, energy balance, and photon diffusion equations including these effects. Within the regime of typical parameters, the two different sources of additional heating have very similar effects: the density profile within the torus becomes shallower both radially and vertically, but for plausible heating rates, there is only minor change (relative to the source-free case) in the distribution of column density with solid angle. The most interesting consequence of distributed heating is that it selects out a relatively narrow range of parameters permitting an equilibrium, particularly $(L/L_E)/\\tau_T$. We discuss the implications of both the narrowness of the permitted range and its approximate coincidence with the range inferred from observations.

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

    SciTech Connect (OSTI)

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

    2008-04-01T23:59:59.000Z

    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 as the July 2006 heat wave in California, suggests that peak electricity demand will challenge current supply, as well as future planned supply capacities when population and income growth are taken into account.

  3. Convergence of the Approximation Scheme to American Option Pricing via the Discrete Morse Semiflow

    SciTech Connect (OSTI)

    Ishii, Katsuyuki, E-mail: ishii@maritime.kobe-u.ac.jp [Kobe University, Graduate School of Maritime Sciences (Japan); Omata, Seiro, E-mail: omata@kenroku.kanazawa-u.ac.jp [Kanazawa University, School of Mathematics and Physics, Institute of Science and Engineering (Japan)

    2011-12-15T23:59:59.000Z

    We consider the approximation scheme to the American call option via the discrete Morse semiflow, which is a minimizing scheme of a time semi-discretized variational functional. In this paper we obtain a rate of convergence of approximate solutions and the convergence of approximate free boundaries. We mainly apply the theory of variational inequalities and that of viscosity solutions to prove our results.

  4. Heat pump system

    DOE Patents [OSTI]

    Swenson, Paul F. (Cleveland, OH); Moore, Paul B. (Fedhaurn, FL)

    1982-01-01T23:59:59.000Z

    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.

  5. Water and Space Heating Heat Pumps 

    E-Print Network [OSTI]

    Kessler, A. F.

    1985-01-01T23:59:59.000Z

    This paper discusses the design and operation of the Trane Weathertron III Heat Pump Water Heating System and includes a comparison of features and performance to other domestic water heating systems. Domestic water is generally provided through...

  6. Water and Space Heating Heat Pumps

    E-Print Network [OSTI]

    Kessler, A. F.

    1985-01-01T23:59:59.000Z

    This paper discusses the design and operation of the Trane Weathertron III Heat Pump Water Heating System and includes a comparison of features and performance to other domestic water heating systems. Domestic water is generally provided through...

  7. Industrial Waste Heat Recovery Using Heat Pipes 

    E-Print Network [OSTI]

    Ruch, M. A.

    1981-01-01T23:59:59.000Z

    For almost a decade now, heat pipes with secondary finned surfaces have been utilized in counter flow heat exchangers to recover sensible energy from industrial exhaust gases. Over 3,000 such heat exchangers are now in service, recovering...

  8. Testing and analysis of immersed heat exchangers

    SciTech Connect (OSTI)

    Farrington, R.B.; Bingham, C.E.

    1986-08-01T23:59:59.000Z

    The objectives were to determine the performance of four immersed, ''supply-side'' heat exchangers used in solar domestic-hot-water systems; to examine the effects of flow rate, temperature difference, and coil configuration on performance; and to develop a simple model to predict the performance of immersed heat exchangers. We tested four immersed heat exchangers: a smooth coil, a finned spiral, a single-wall bayonet, and a double-wall bayonet. We developed two analyticl models and a simple finite difference model. We experimentally verified that the performance of these heat exchangers depends on the flow rate through them; we also showed that the temperature difference between the heat exchanger's inlet and the storage tank can strongly affect a heat exchanger's performance. We also compared the effects of the heat exchanger's configuration and correlated Nusselt and Rayleigh numbers for each heat exchanger tested. The smooth coil had a higher effectiveness than the others, while the double-wall bayonet had a very low effectiveness. We still do not know the long-term effectiveness of heat exchangers regarding scale accumulation, nor do we know the effects of very low flow rates on a heat exchanger's performance.

  9. Radiative heat transfer in porous uranium dioxide

    SciTech Connect (OSTI)

    Hayes, S.L. [Texas A and M Univ., College Station, TX (United States)] [Texas A and M Univ., College Station, TX (United States)

    1992-12-01T23:59:59.000Z

    Due to low thermal conductivity and high emissivity of UO{sub 2}, it has been suggested that radiative heat transfer may play a significant role in heat transfer through pores of UO{sub 2} fuel. This possibility was computationally investigated and contribution of radiative heat transfer within pores to overall heat transport in porous UO{sub 2} quantified. A repeating unit cell was developed to model approximately a porous UO{sub 2} fuel system, and the heat transfer through unit cells representing a wide variety of fuel conditions was calculated using a finite element computer program. Conduction through solid fuel matrix as wekk as pore gas, and radiative exchange at pore surface was incorporated. A variety of pore compositions were investigated: porosity, pore size, shape and orientation, temperature, and temperature gradient. Calculations were made in which pore surface radiation was both modeled and neglected. The difference between yielding the integral contribution of radiative heat transfer mechanism to overall heat transport. Results indicate that radiative component of heat transfer within pores is small for conditions representative of light water reactor fuel, typically less than 1% of total heat transport. It is much larger, however, for conditions present in liquid metal fast breeder reactor fuel; during restructuring of this fuel type early in life, the radiative heat transfer mode was shown to contribute as much as 10-20% of total heat transport in hottest regions of fuel.

  10. Heating systems for heating subsurface formations

    DOE Patents [OSTI]

    Nguyen, Scott Vinh (Houston, TX); Vinegar, Harold J. (Bellaire, TX)

    2011-04-26T23:59:59.000Z

    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.

  11. Development of a compensation chamber for use in a multiple condenser loop heat pipe

    E-Print Network [OSTI]

    Roche, Nicholas Albert

    2013-01-01T23:59:59.000Z

    The performance of many electronic devices is presently limited by heat dissipation rates. One potential solution lies in high-performance air-cooled heat exchangers like PHUMP, the multiple condenser loop heat pipe presented ...

  12. Rheology and Convective Heat Transfer of Colloidal Gas Aphrons in Horizontal Minichannels

    E-Print Network [OSTI]

    Tseng, H.; Pilon, L.; Warrier, G.

    2006-01-01T23:59:59.000Z

    volumetric flow rates and heat input of 2.68×10 -6 m 3 /s attime for different heat input but identical pump setting.per channel, m 3 /s total heat input in the five channels, W

  13. Building wall heat flux calculations

    SciTech Connect (OSTI)

    Park, J.E.; Kirkpatrick, J.R.; Tunstall, J.N.; Childs, K.W.

    1987-01-01T23:59:59.000Z

    Calculations of the heat transfer through the standard stud wall structure of a residential building are described. The wall cavity contains no insulation. Four of the five test cases represent progressively more complicated approximations to the heat transfer through and within a hollow wall structure. The fifth adds the model components necessary to severely inhibit the radiative energy transport across the empty cavity. Flow within the wall cavity is calculated from the Navier-Stokes equations and the energy conservation equation for an ideal gas using the Implicit Compressible Eulerian (ICE) algorithm. The fluid flow calculation is coupled to the radiation-conduction model for the solid portions of the system. Conduction through sill plates is about 4% of the total heat transferred through a composite wall.

  14. An analytical model for the design of in-slab electric heating panels

    SciTech Connect (OSTI)

    Ritter, T.L.; Kilkis, B.I. [Heatway, Springfield, MO (United States)

    1998-10-01T23:59:59.000Z

    In this paper, a steady-state heat transfer model is described for design and sizing of electric radiant panel heating systems embedded in a slab. This model is applicable both for ceiling and floor panels. An approximate panel surface heat output algorithm is also given as a function of size and orientation of the heated space and outdoor exposure.

  15. Research Note on a Parabolic Heat-Balance Integral Method with Unspecified Exponent: An Entropy Generation Approach in Optimal Profile Determination

    E-Print Network [OSTI]

    Jordan Hristov

    2010-12-12T23:59:59.000Z

    The heat-balance integral method of Goodman is studied with two simple 1-D heat conduction problems with prescribed temperature and flux boundary conditions. These classical problems with well known exact solutions enable to demonstrate the heat-balance integral method performance by a parabolic profile and the entropy generation minimization concept in definition of the appropriate profile exponent. The basic assumption generating the additional constraints needed to perform the solution is based on the requirement to minimize the difference in the local thermal entropy generation rates calculated by the approximate and the exact profile, respectively. This concept is easily applicable since the general concept has simple implementation of the condition requiring the thermal entropy generations calculated through both profiles to be the same at the boundary. The entropy minimization generation approach automatically generates the additional requirement which is deficient in the set of conditions defined by the heat-balance integral method concept.

  16. Dead heat

    SciTech Connect (OSTI)

    Oppenheimer, M.; Boyle, R.H.

    1990-01-01T23:59:59.000Z

    This paper reports on the prospect of global warming. This paper proposes a workable solution, and a road map for getting there. The author explains how we became addicted to fossil fuels and evokes a bleak picture should this dependence continue. But the book also explores how industry can become a vehicle for solving, instead of precipitating, the global environmental crisis. The decoupling of energy from pollution can be accomplished without sacrificing prosperity by powering the economy with solar energy. Dead Heat takes us step by step to a greenhouse-friendly world fueled only by the sun.

  17. Spring 2014 Heat Transfer -1

    E-Print Network [OSTI]

    Virginia Tech

    Spring 2014 1 Heat Transfer - 1 Consider a cylindrical nuclear fuel rod of length L and diameter df the fuel rod, and the volumetric generation rate is known to vary sinusoidally with distance along the rod to exist between the surface of the rod and the water. Axial conduction can be neglected in rod and fluid

  18. Convex approximations in stochastic programming by semidefinite ...

    E-Print Network [OSTI]

    2010-04-19T23:59:59.000Z

    This experience leads us to force the convexity of the approximating quadratic ..... As we can see, the least-squares approximation works well only if the data ...

  19. Dual source heat pump

    DOE Patents [OSTI]

    Ecker, Amir L. (Dallas, TX); Pietsch, Joseph A. (Dallas, TX)

    1982-01-01T23:59:59.000Z

    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.

  20. Segmented heat exchanger

    DOE Patents [OSTI]

    Baldwin, Darryl Dean (Lafayette, IN); Willi, Martin Leo (Dunlap, IL); Fiveland, Scott Byron (Metamara, IL); Timmons, Kristine Ann (Chillicothe, IL)

    2010-12-14T23:59:59.000Z

    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.

  1. Rates and Repayment Services

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

    Tariff Rates FY 2015 Rates and Rate Schedules **Effective October 1, 2014** FY 2014 Rates and Rate Schedules FY 2013 Rates and Rate Schedules FY 2012 Rates and Rate Schedules FY...

  2. Comparative evaluation of the impacts of domestic gas and electric heat pump heating on air pollution in California. Final report

    SciTech Connect (OSTI)

    Ganji, A. [San Francisco State Univ., CA (United States). Div. of Engineering

    1992-07-01T23:59:59.000Z

    Residential space and water heating accounts for approximately 12% of California`s and 15% of the United States, energy consumption. most Of the residential heating is by direct use of natural gas. combustion of natural gas is a contributor to the overall air pollution,, especially CO and NO{sub x} in the urban areas. Another efficient method for domestic water and space heating is use of electric heat pumps, the most popular category of which uses air as its heat source. Electric heat pumps do not emit air pollutants at the point of use, but use electric power, which is a major contributor to air pollution at its point of generation from fossil fuels. It is the specific objective of this report to evaluate and compare the energy efficiency and source air pollutants of natural gas heaters and electric heat pumps used for domestic heating. Effect of replacing natural gas heaters with electric heat pumps on air pollutant emissions due to domestic heating in two urban areas and in California as a whole has also been evaluated. The analysis shows that with the present state of technology, electric heat pumps have higher heating efficiencies than natural gas heaters. Considering the current electricity generation mix in the US, electric heat pumps produce two to four times more NO{sub x}, much less CO, and comparable amount of CO{sub 2} per unit of useful heating energy compared to natural gas heaters. With California mix, electric heat pumps produce comparable NO{sub x} and much less CO and approximately 30% less CO{sub 2} per unit heat output. Replacement of natural gas heaters with electric heat pumps will slightly increase the overall NO{sub x}, and reduce CO and CO{sub 2} emissions in California. The effect of advanced technology power generation and heat pump heating has also been analyzed.

  3. Comparative evaluation of the impacts of domestic gas and electric heat pump heating on air pollution in California

    SciTech Connect (OSTI)

    Ganji, A. (San Francisco State Univ., CA (United States). Div. of Engineering)

    1992-07-01T23:59:59.000Z

    Residential space and water heating accounts for approximately 12% of California's and 15% of the United States, energy consumption. most Of the residential heating is by direct use of natural gas. combustion of natural gas is a contributor to the overall air pollution,, especially CO and NO{sub x} in the urban areas. Another efficient method for domestic water and space heating is use of electric heat pumps, the most popular category of which uses air as its heat source. Electric heat pumps do not emit air pollutants at the point of use, but use electric power, which is a major contributor to air pollution at its point of generation from fossil fuels. It is the specific objective of this report to evaluate and compare the energy efficiency and source air pollutants of natural gas heaters and electric heat pumps used for domestic heating. Effect of replacing natural gas heaters with electric heat pumps on air pollutant emissions due to domestic heating in two urban areas and in California as a whole has also been evaluated. The analysis shows that with the present state of technology, electric heat pumps have higher heating efficiencies than natural gas heaters. Considering the current electricity generation mix in the US, electric heat pumps produce two to four times more NO{sub x}, much less CO, and comparable amount of CO{sub 2} per unit of useful heating energy compared to natural gas heaters. With California mix, electric heat pumps produce comparable NO{sub x} and much less CO and approximately 30% less CO{sub 2} per unit heat output. Replacement of natural gas heaters with electric heat pumps will slightly increase the overall NO{sub x}, and reduce CO and CO{sub 2} emissions in California. The effect of advanced technology power generation and heat pump heating has also been analyzed.

  4. 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...

  5. Geothermal heat pumps for heating and cooling

    SciTech Connect (OSTI)

    Garg, S.C.

    1994-03-01T23:59:59.000Z

    Naval Facilities Engineering Service Center (NFESC) has been tasked by Naval Shore Facilities Energy Office to evaluate the NAS Patuxent River ground-source heat pump (GHP) installation. A large part of a building`s energy consumption consists of heating and air conditioning for occupant comfort. The space heating requirements are normally met by fossil-fuel-fired equipment or electric resistance heating. Cooling is provided by either air conditioners or heat pumps, both using electricity as an energy source.

  6. Rates and Repayment Services

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

    Customer Letter - Preliminary Review of Drought Adder Component for 2011 Firm Power Rates 2015 Rates and Rate Schedule - Current * 2010 Rates and Rate Schedule 2009 Rates and...

  7. Rates and Repayment Services

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

    Rates and Repayment Services Consolidated Rate Schedules FY 2015 Consolidated Rate Schedules FY 2014 Rates BCP Annual Rate Process Central Arizona Project Transmission Rate Process...

  8. Building wall heat flux calculations

    SciTech Connect (OSTI)

    Park, J.E.; Kirkpatrick, J.R.; Tunstall, J.N.; Childs, K.W.

    1987-06-01T23:59:59.000Z

    Calculations of the heat transfer through the standard stud wall structure of a residential building are described. The wall cavity contains no insulation. Four of the five test cases represent progressively more complicated approximations to the heat transfer through and within a hollow wall structure. The fifth adds the model components necessary to severely inhibit the radiative energy transport across the empty cavity. Flow within the wall cavity is calculated from the Navier-Stokes equations and the energy conservation equation for an ideal gas using the Implicit Compressible Eulerian (ICE) algorithm. The fluid flow calculation is coupled to the radiation-conduction model for the solid portions of the system. Conduction through sill plates is about 4% of the total heat transferred through a composite wall. All of the other model elements (conduction through wall board, sheathing, and siding; convection from siding and wallboard to ambients; and radiation across the wall cavity) are required to accurately predict the heat transfer through a wall. Addition of a foil liner on one inner surface of the wall cavity reduces the total heat transferred by almost 50%.

  9. Heating 7. 2 user's manual

    SciTech Connect (OSTI)

    Childs, K.W.

    1993-02-01T23:59:59.000Z

    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.

  10. Influence of Infrared Radiation on Attic Heat Transfer 

    E-Print Network [OSTI]

    Katipamula, S.; Turner, W. D.; Murphy, W. E.; O'Neal, D. L.

    1985-01-01T23:59:59.000Z

    roof temperatures. It was found that a radiant barrier such as aluminum foil can reduce the heat flux significantly. Experimental results were compared to a Three-Region approximate solution developed at Oak Ridge National Laboratories (ORNL). The model...

  11. Approximating Metal-Insulator Transitions

    E-Print Network [OSTI]

    C. Danieli; K. Rayanov; B. Pavlov; G. Martin; S. Flach

    2014-05-06T23:59:59.000Z

    We consider quantum wave propagation in one-dimensional quasiperiodic lattices. We propose an iterative construction of quasiperiodic potentials from sequences of potentials with increasing spatial period. At each finite iteration step the eigenstates reflect the properties of the limiting quasiperiodic potential properties up to a controlled maximum system size. We then observe approximate metal-insulator transitions (MIT) at the finite iteration steps. We also report evidence on mobility edges which are at variance to the celebrated Aubry-Andre model. The dynamics near the MIT shows a critical slowing down of the ballistic group velocity in the metallic phase similar to the divergence of the localization length in the insulating phase.

  12. Mpemba effect, Newton cooling law and heat transfer equation

    E-Print Network [OSTI]

    Vladan Pankovic; Darko V. Kapor

    2012-12-11T23:59:59.000Z

    In this work we suggest a simple theoretical solution of the Mpemba effect in full agreement with known experimental data. This solution follows simply as an especial approximation (linearization) of the usual heat (transfer) equation, precisely linearization of the second derivation of the space part of the temperature function (as it is well-known Newton cooling law can be considered as the effective approximation of the heat (transfer) equation for constant space part of the temperature function).

  13. Heat-Of-Reaction Chemical Heat Pumps--Possible Configurations 

    E-Print Network [OSTI]

    Kirol, L. D.

    1986-01-01T23:59:59.000Z

    Chemical heat pumps utilize working fluids which undergo reversible chemical changes. Mechanically driven reactive heat pump cycles or, alternatively, heat driven heat pumps in which either heat engine or heat pump working fluid is reactive...

  14. Multiple source heat pump

    DOE Patents [OSTI]

    Ecker, Amir L. (Duncanville, TX)

    1983-01-01T23:59:59.000Z

    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.

  15. Calculation of tunneling rates across a barrier with continuous potential

    E-Print Network [OSTI]

    Sina Khorasani

    2011-04-10T23:59:59.000Z

    Here, approximate, but accurate expressions for calculation of wavefunctions and tunneling rates are obtained using the method of uniform asymptotic expansion.

  16. Does Growth Rate Determine the Rate of Metabolism in Shorebird Chicks Living in the Arctic?

    E-Print Network [OSTI]

    Williams, Jos. B.

    primarily of greater metabolic inten- sities of heat-generating tissues. The maximum temperature gradient500 Does Growth Rate Determine the Rate of Metabolism in Shorebird Chicks Living in the Arctic/22/2007; Electronically Published 7/13/2007 ABSTRACT We measured resting and peak metabolic rates (RMR and PMR

  17. Waste Heat Recovery – Submerged Arc Furnaces (SAF) 

    E-Print Network [OSTI]

    O'Brien, T.

    2008-01-01T23:59:59.000Z

    designed consumes power and fuel that yields an energy efficiency of approximately 40% (Total Btu’s required to reduce to elemental form/ Btu Input). The vast majority of heat is lost to the atmosphere or cooling water system. The furnaces can be modified...

  18. San Bernardino District Heating District Heating Low Temperature...

    Open Energy Info (EERE)

    San Bernardino District Heating District Heating Low Temperature Geothermal Facility Facility San Bernardino District Heating Sector Geothermal energy Type District Heating...

  19. 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...

  20. Boise City Geothermal District Heating District Heating Low Temperatur...

    Open Energy Info (EERE)

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

  1. 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...

  2. Midland District Heating District Heating Low Temperature Geothermal...

    Open Energy Info (EERE)

    Midland District Heating District Heating Low Temperature Geothermal Facility Facility Midland District Heating Sector Geothermal energy Type District Heating Location Midland,...

  3. 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...

  4. Northeast Home Heating Oil Reserve System Heating Oil, PIA Office...

    Energy Savers [EERE]

    Northeast Home Heating Oil Reserve System Heating Oil, PIA Office of Fossil Energy Headquaters Northeast Home Heating Oil Reserve System Heating Oil, PIA Office of Fossil Energy...

  5. Application Study of a Single House Horizontal Heating System 

    E-Print Network [OSTI]

    Hang, Y.; Ying, D.

    2006-01-01T23:59:59.000Z

    the different forms of heating systems suited for single household metering. We introduce especially the single house horizontal spanning system and show how to select the heat flow rate of the radiator. We also study the distribution rule of the heat...

  6. Thermophoretic interaction of heat releasing particles Yu. Dolinskya)

    E-Print Network [OSTI]

    Elperin, Tov

    Thermophoretic interaction of heat releasing particles Yu. Dolinskya) and T. Elperinb) Department investigates thermophoretic force acting at heat releasing absorbing particles near the interface between two of the thermophoretic force is proportional to the rate of heat release absorption by the particle, and its direction

  7. Intergalactic dust and its photoelectric heating

    E-Print Network [OSTI]

    Akio K. Inoue; Hideyuki Kamaya

    2008-10-31T23:59:59.000Z

    We have examined the dust photoelectric heating in the intergalactic medium (IGM). The heating rate in a typical radiation field of the IGM is represented by $\\Gamma_{\\rm pe} = 1.2\\times10^{-34}$ erg s$^{-1}$ cm$^{-3}$ $({\\cal D}/10^{-4})(n_{\\rm H}/10^{-5} {\\rm cm^{-3}})^{4/3} (J_{\\rm L}/10^{-21} {\\rm erg s^{-1} cm^{-2} Hz^{-1} sr^{-1}})^{2/3} (T/10^4 {\\rm K})^{-1/6}$, where ${\\cal D}$ is the dust-to-gas mass ratio, $n_{\\rm H}$ is the hydrogen number density, $J_{\\rm L}$ is the mean intensity at the hydrogen Lyman limit of the background radiation, and $T$ is the gas temperature, if we assume the new X-ray photoelectric yield model by Weingartner et al. (2006) and the dust size distribution in the Milky Way by Mathis, Rumpl, & Nordsieck (1977). This heating rate dominates the HI and HeII photoionization heating rates when the hydrogen number density is less than $\\sim10^{-6}$ cm$^{-3}$ if ${\\cal D}=10^{-4}$ which is 1% of that in the Milky Way, although the heating rate is a factor of 2--4 smaller than that with the old yield model by Weingartner & Draine (2001). The grain size distribution is very important. If only large ($\\ge0.1$ $\\mu$m) grains exist in the IGM, the heating rate is reduced by a factor of $\\simeq5$. Since the dust heating is more efficient in a lower density medium relative to the photoionization heating, it may cause an inverted temperature--density relation in the low density IGM suggested by Bolton et al. (2008). Finally, we have found that the dust heating is not very important in the mean IGM before the cosmic reionization.

  8. Heat Pump for High School Heat Recovery 

    E-Print Network [OSTI]

    Huang, K.; Wang, H.; Zhou, X.

    2006-01-01T23:59:59.000Z

    The heat pump system used for recycling and reusing waste heat in s high school bathroom was minutely analyzed in its coefficient of performance, onetime utilization ratio of energy, economic property and so on. The results showed that this system...

  9. Industrial Waste Heat Recovery Using Heat Pipes

    E-Print Network [OSTI]

    Ruch, M. A.

    1981-01-01T23:59:59.000Z

    -expanding variety of industrial processes. One notable application in recent years has been for combustion airs preheat of fired heaters in petroleum refineries and petrochemical plants. Another recent development has been a waste heat recovery boiler using heat...

  10. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, Gershon (Oak Ridge, TN)

    1984-01-01T23:59:59.000Z

    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.

  11. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, G.

    1982-06-16T23:59:59.000Z

    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.

  12. Locating Heat Recovery Opportunities 

    E-Print Network [OSTI]

    Waterland, A. F.

    1981-01-01T23:59:59.000Z

    Basic concepts of heat recovery are defined as they apply to the industrial community. Methods for locating, ranking, and developing heat recovery opportunities are presented and explained. The needs for useful heat 'sinks' are emphasized as equal...

  13. Locating Heat Recovery Opportunities

    E-Print Network [OSTI]

    Waterland, A. F.

    1981-01-01T23:59:59.000Z

    Basic concepts of heat recovery are defined as they apply to the industrial community. Methods for locating, ranking, and developing heat recovery opportunities are presented and explained. The needs for useful heat 'sinks' are emphasized as equal...

  14. Photovoltaic roof heat flux

    E-Print Network [OSTI]

    Samady, Mezhgan Frishta

    2011-01-01T23:59:59.000Z

    transient the heat transfer model. T h i s required the roofto develop and calibrate heat transfer models to be able toE S station, the heat transfer models described i n sections

  15. Design of chemical reactors of the heat exchanger type

    E-Print Network [OSTI]

    McBeth, Lloyd Theodore

    1956-01-01T23:59:59.000Z

    , of the coolant varies with respect to its position in the tubes. A heat balance on the reactants is shown below. Heat balance on the reacting mass during time ae Heat in by generation = rV QR& 9 R R Heat transferred from p i = the tubes to the mass: na... at constant temper- ature, less and less heat must be removed as the reaction proceeds. This is accomplished by the gradual reduction of the coolant flow rate. A mefhod for the determination of the inanner in which the coolant rate must be varied...

  16. Woven heat exchanger

    DOE Patents [OSTI]

    Piscitella, R.R.

    1984-07-16T23:59:59.000Z

    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.

  17. Rates and Repayment Services

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

    Rates and Repayment Services Rates Loveland Area Projects Firm Power Rates Open Access Transmission Tariff Rates Chart of Loveland Area Projects Historical Transmission Rates...

  18. HEATING AND COOLING PROTOSTELLAR DISKS

    SciTech Connect (OSTI)

    Hirose, S. [Institute for Research on Earth Evolution, Japan Agency for Marine-Earth Science and Technology, 3173-25 Showamachi, Kanazawa-ku, Yokohama, Kanagawa 236-0001 (Japan); Turner, N. J., E-mail: shirose@jamstec.go.jp, E-mail: neal.turner@jpl.nasa.gov [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)

    2011-05-10T23:59:59.000Z

    We examine heating and cooling in protostellar disks using three-dimensional radiation-MHD calculations of a patch of the Solar nebula at 1 AU, employing the shearing-box and flux-limited radiation diffusion approximations. The disk atmosphere is ionized by stellar X-rays, well coupled to magnetic fields, and sustains a turbulent accretion flow driven by magnetorotational instability, while the interior is resistive and magnetically dead. The turbulent layers are heated by absorbing the light from the central star and by dissipating the magnetic fields. They are optically thin to their own radiation and cool inefficiently. The optically thick interior in contrast is heated only weakly, by re-emission from the atmosphere. The interior is colder than a classical viscous model and isothermal. The magnetic fields support an extended atmosphere that absorbs the starlight 1.5 times higher than the hydrostatic viscous model. The disk thickness thus measures not the internal temperature, but the magnetic field strength. Fluctuations in the fields move the starlight-absorbing surface up and down. The height ranges between 13% and 24% of the radius over timescales of several orbits, with implications for infrared variability. The fields are buoyant, so the accretion heating occurs higher in the atmosphere than the stresses. The heating is localized around current sheets, caused by magnetorotational instability at lower elevations and by Parker instability at higher elevations. Gas in the sheets is heated above the stellar irradiation temperature, even though accretion is much less than irradiation power when volume averaged. The hot optically thin current sheets might be detectable through their line emission.

  19. Total Space Heat-

    Annual Energy Outlook 2013 [U.S. Energy Information Administration (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...

  20. 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...

  1. Modeling Thermal-Hydrologic Processes for a Heated Fractured Rock System: Impact of a Capillary-Pressure Maximum

    E-Print Network [OSTI]

    Sun, Y.; Buscheck, T. A.; Lee, K. H.; Hao, Y.; James, S. C.

    2010-01-01T23:59:59.000Z

    package spac- ing and waste-package heat generation rate,Radioactive heat of decay from waste packages emplaced inwaste packages and emplacement drifts, and for heat ?ow at

  2. Reflectance Function Approximation for Material Classification

    E-Print Network [OSTI]

    Dyer, Charles R.

    Reflectance Function Approximation for Material Classification Edward Wild CS 766 Final Project This report summarizes the results of a project to approximate reflectance functions and classify materials to classify materials. Classification algorithms are proposed to deal with unseen materials. Experimental

  3. Analysis of radial fin assembly heat transfer with dehumidification

    SciTech Connect (OSTI)

    Rosario, L.; Rahman, M.M. [Univ. of South Florida, Tampa, FL (United States). Dept. of Mechanical Engineering

    1996-12-31T23:59:59.000Z

    The aim of this paper is the analysis of heat transfer in a radial fin assembly during the process of dehumidification. An individual finned tube geometry is a reasonable representation of heat exchangers used in air conditioning. The condensation process involves both heat and mass transfer and the cooling takes place by the removal of sensible as well as latent heat. The ratio of sensible to total heat is an important quantity that defines the heat transfer process during a dehumidifier operation. A one-dimensional model for heat transfer in the fin and the heat exchanger block is developed to study the effects of condensation on the fin surface. The combined heat and mass transfer process is modeled by incorporating the ratio of sensible to total heat in the formulation. The augmentation of heat transfer due to fin was established by comparing heat transfer rate with and without fins under the same operating conditions. Numerical calculations were carried out to study the effects of relative humidity and dry bulb temperature of the incoming air, and cold fluid temperature inside the coil on the performance of the heat exchanger. Results were compared to those published for rectangular fin under humid condition showed excellent agreement when the present model was used to compute that limiting condition. It was found that the heat transfer rate increased with increment in both dry bulb temperature and relative humidity of the air. The augmentation factor, however, decreased with increment in relative humidity and the dry bulb temperature.

  4. Constructal multi-scale package of vertical channels with natural convection and maximal heat transfer density. CONSTRUCTAL DESIGN: THE GENERATION OF MULTI-SCALE HEAT

    E-Print Network [OSTI]

    Kihm, IconKenneth David

    transfer density. CONSTRUCTAL DESIGN: THE GENERATION OF MULTI-SCALE HEAT AND FLUID FLOW STRUCTURES-scale structures in natural convection with the objective of maximizing the heat transfer density, or the heat transfer rate per unit of volume§ . The flow volume is filled with vertical equidistant heated blades

  5. Kinetic Modeling and Thermodynamic Closure Approximation of ...

    E-Print Network [OSTI]

    2007-10-03T23:59:59.000Z

    Oct 5, 2007 ... Kinetic Modeling and Thermodynamic Closure. Approximation of Liquid Crystal Polymers. Haijun Yu. Program in Applied and Computational ...

  6. Fast Local Approximation to Global Illumination

    E-Print Network [OSTI]

    Wyman, Chris

    based technique #12;Approach to Shadows · Assume: ­ Approximate shadow umbra with hard shadow ­ Object

  7. Radiative heating of the ISCCP upper level cloud regimes and its impact on the large-scale tropical circulation

    E-Print Network [OSTI]

    Radiative heating of the ISCCP upper level cloud regimes and its impact on the large-scale tropical 2012; accepted 14 December 2012; published 31 January 2013. [1] Radiative heating profiles. The resulting radiative heating profiles have maxima of approximately 1 K/day near 12 km, with equal heating

  8. Cab Heating and Cooling

    SciTech Connect (OSTI)

    Damman, Dennis

    2005-10-31T23:59:59.000Z

    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.

  9. Fragmentation of suddenly heated liquids

    SciTech Connect (OSTI)

    Blink, J.A.

    1985-03-01T23:59:59.000Z

    Fragmentation of free liquids in Inertial Confinement Fusion reactors could determine the upper bound on reactor pulse rate. The x-ray ablated materials must cool and recondense to allow driver beam propagation. The increased surface area caused by fragmentation will enhance the cooling and condensation rates. Relaxation from the suddenly heated state will move a liquid into the negative pressure region under the liquid-vapor P-V dome. The lithium equation of state was used to demonstrate that neutron-induced vaporization uses only a minor fraction of the added heat, much less than would be required to drive the expansion. A 77% expansion of the lithium is required before the rapid vaporization process of spinodal decomposition could begin, and nucleation and growth are too slow to contribute to the expansion.

  10. The Influence of Heat-Treatment Temperature on the Cation Distribution of LiNi0.5Mn0.5O2 and Its Rate Capability in Lithium Rechargeable Batteries

    SciTech Connect (OSTI)

    N Yabuuchi; Y Lu; A Mansour; S Chen; Y Shao-Horn

    2011-12-31T23:59:59.000Z

    LiNi{sub 0.5}Mn{sub 0.5}O{sub 2} samples were prepared from NiMnO{sub 3} and Li{sub 2}CO{sub 3} in a range of temperatures from 900 to 1050 C. Synchrotron X-ray diffraction analysis combined with X-ray absorption spectroscopy showed that LiNi{sub 0.5}Mn{sub 0.5}O{sub 2} segregated into one major Ni{sup 2+}O-enriched phase and one minor Li{sub 2}Mn{sup 4+}O{sub 3}-enriched phase, where the extent of segregation decreased with increasing synthesis temperature from 900 to 1050 C. Scanning and transmission electron microscopy combined with energy dispersive X-ray spectroscopy revealed that the segregated domains exist in individual particles. Although all of the LiNi{sub 0.5}Mn{sub 0.5}O{sub 2} samples showed comparable specific capacity ({approx}200 mAh/g) and capacity retention at low current densities, the rate capability of LiNi{sub 0.5}Mn{sub 0.5}O{sub 2} of 900 C is lower than that of LiNi{sub 0.5}Mn{sub 0.5}O{sub 2} of 1000 C. As X-ray photoelectron spectroscopy analysis showed that all of the LiNi{sub 0.5}Mn{sub 0.5}O{sub 2} samples had comparable surface chemistry, the higher rate capability of LiNi{sub 0.5}Mn{sub 0.5}O{sub 2} of 1000 C can be attributed to reduced cation segregation of Ni{sup 2+}O-enriched domains in the layered structure of the major phase, having potentially faster lithium diffusion than that of LiNi{sub 0.5}Mn{sub 0.5}O{sub 2} of 900 C.

  11. 5. Heat transfer Ron Zevenhoven

    E-Print Network [OSTI]

    Zevenhoven, Ron

    ) Heat conductance as Gheat =1/Rheat = Q/T (unit: W/K or W/°C) For a plane material with thickness L (m) and conductivity (W/mK): Gheat = ·A/L Rheat = L/(·A) . . . Åbo Akademi University | Thermal and Flow Engineering rate Q through a cross-sectional area A (m2). If is a constant: with thermal conductivity , unit: W

  12. Resonances and the thermonuclear reaction rate

    E-Print Network [OSTI]

    M. S. Hussein; M. Ueda; A. J. Sargeant; M. P. Pato

    2003-07-21T23:59:59.000Z

    We present an approximate analytic expression for thermonuclear reaction rate of charged particles when the cross section contains a single narrow or wide resonance described by a Breit-Wigner shape. The resulting expression is uniformly valid as the effective energy and resonance energy coalesce. We use our expressions to calculate the reaction rate for $^{12}$C(p,$\\gamma$)$^{13}$N.

  13. Rotary magnetic heat pump

    DOE Patents [OSTI]

    Kirol, Lance D. (Shelly, ID)

    1988-01-01T23:59:59.000Z

    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.

  14. Rotary magnetic heat pump

    DOE Patents [OSTI]

    Kirol, L.D.

    1987-02-11T23:59:59.000Z

    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.

  15. Mass and Heat Recovery 

    E-Print Network [OSTI]

    Hindawai, S. M.

    2010-01-01T23:59:59.000Z

    In the last few years heat recovery was under spot and in air conditioning fields usually we use heat recovery by different types of heat exchangers. The heat exchanging between the exhaust air from the building with the fresh air to the building...

  16. Shape-independent limits to near-field radiative heat transfer

    E-Print Network [OSTI]

    Miller, Owen D; Rodriguez, Alejandro W

    2015-01-01T23:59:59.000Z

    We derive shape-independent limits to the spectral radiative heat-transfer rate between two closely spaced bodies, generalizing the concept of a black body to the case of near-field energy transfer. By conservation of energy, we show that each body of susceptibility $\\chi$ can emit and absorb radiation at enhanced rates bounded by $|\\chi|^2 / \\operatorname{Im} \\chi$, optimally mediated by near-field photon transfer proportional to $1/d^2$ across a separation distance $d$. Dipole--dipole and dipole--plate structures approach restricted versions of the limit, but common large-area structures do not exhibit the material enhancement factor and thus fall short of the general limit. By contrast, we find that particle arrays interacting in an idealized Born approximation exhibit both enhancement factors, suggesting the possibility of orders-of-magnitude improvement beyond previous designs and the potential for radiative heat transfer to be comparable to conductive heat transfer through air at room temperature, and s...

  17. Infrared Emission from Interstellar Dust. I. Stochastic Heating of Small Grains

    E-Print Network [OSTI]

    B. T. Draine; Aigen Li

    2000-11-16T23:59:59.000Z

    We present a method for calculating the infrared emission from a population of dust grains heated by starlight, including very small grains for which stochastic heating by starlight photons results in high temperature transients. Because state-to-state transition rates are generally unavailable for complex molecules, we consider model PAH, graphitic, and silicate grains with realistic vibrational mode spectra and realistic radiative properties. The vibrational density of states is used in a statistical-mechanical description of the emission process. Unlike previous treatments, our approach fully incorporates multiphoton heating effects, important for large grains or strong radiation fields. We discuss how the "temperature" of the grain is related to its vibrational energy. By comparing with an "exact" statistical calculation of the emission process, we determine the conditions under which the "thermal" and the "continuous cooling" approximations can be used to calculate the emission spectrum. We present results for the infrared emission spectra of PAH grains of various sizes heated by starlight. We show how the relative strengths of the 6.2, 7.7, and 11.3um features depend on grain size, starlight spectrum and intensity, and grain charging conditions. We show results for grains in the "cold neutral medium", "warm ionized medium", and representative conditions in photodissociation regions. Our model results are compared to observed ratios of emission features for reflection nebulae and photodissociation regions, the Milky Way, normal spiral galaxies, and starburst galaxies.

  18. Thulium-170 heat source

    DOE Patents [OSTI]

    Walter, Carl E. (Pleasanton, CA); Van Konynenburg, Richard (Livermore, CA); VanSant, James H. (Tracy, CA)

    1992-01-01T23:59:59.000Z

    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.

  19. Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow

    E-Print Network [OSTI]

    Boyer, Edmond

    Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow S in a rotor-stator cavity subjected to a superimposed throughflow with heat transfer. Nu- merical predictions field from the heat transfer process. The turbulent flux is approximated by a gradient hypothesis

  20. Thermoelectric heat exchange element

    DOE Patents [OSTI]

    Callas, James J. (Peoria, IL); Taher, Mahmoud A. (Peoria, IL)

    2007-08-14T23:59:59.000Z

    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.

  1. Mass and Heat Recovery

    E-Print Network [OSTI]

    Hindawai, S. M.

    2010-01-01T23:59:59.000Z

    - 1 - MASS AND HEAT RECOVERY SYSTEM SALAH MAHMOUD HINDAWI DIRECTOR HINDAWI FOR ENGINEERING SERVICES & CONTRACTING NEW DAMIETTA , EGYPT ABSTRACT : In the last few years heat recovery was under spot . and in air conditioning fields... ) as a heat recovery . and I use the water as a mass recovery . The source of mass and heat recovery is the condensate water which we were dispose and connect it to the drain lines . THE BENEFIT OF THIS SYSTEM ARE : 1) Using the heat energy from...

  2. Dealing with Uncertainties During Heat Exchanger Design

    E-Print Network [OSTI]

    Polley, G. T.; Pugh, S. J.

    heat capacity flow rate of 30 kW/K. The cold stream flowing through E I bas a heat capacity flow rate of 55 kW/K and that flowing through E2 a value of 35 kW/K. 123 ESL-IE-01-05-20 Proceedings from the Twenty-third National Industrial Energy... Technology Conference, Houston, TX, May 1-4, 2001 E2 Area = 100 m 2 cp= 35 kW/K El Area = 300 m 2 Figure 1. Simple Heat Exchanger Network CP = 30 kW/K CP= 55 kWIK Assume that exchangers EI (of heat transfer area 100 m 2 ) and E2 (of 300 m 2...

  3. The cyclo-synchrotron process and particle heating through the absorption of photons

    E-Print Network [OSTI]

    K. Katarzynski; G. Ghisellini; R. Svensson; J. Gracia

    2006-02-08T23:59:59.000Z

    We propose a new approximation for the cyclo-synchrotron emissivity of a single electron. In the second part of this work, we discuss a simple application for our approximation, and investigate the heating of electrons through the self-absorption process. Finally, we investigate the self-absorbed part of the spectrum produced by a power-law population of electrons. In comparison to earlier approximations, our formula provides a few significant advantages. Integration of the emissivity over the whole frequency range, starting from the proper minimal emitting frequency, gives the correct cooling rate for any energy particle. Further, the spectrum of the emission is well approximated over the whole frequency range, even for relatively low particle energies (beta energy particles, independent of the shape of the particle distribution responsible for the self-absorbed synchrotron emission. We find that the energy gains for low energy particles are always higher than energy losses by cyclo-synchrotron emission. We show also that the spectral index of the self-absorbed part of the spectrum at very low frequencies differs significantly from the well known standard relation I(nu) ~ nu^(5/2).

  4. Heat Integrate Heat Engines in Process Plants

    E-Print Network [OSTI]

    Hindmarsh, E.; Boland, D.; Townsend, D. W.

    ~C. T min Table 3. Problem Table Algorithm Applied to Petrochemicals Process Interval GJ ltiour 'Temperatures ! C! 2 ) ? ~ Cold. Hot Aecumulated Heat Heat FJ.owa Interval Streams StrePlS Deficit. Input OUtput -OUtt!utInput. 20 30 -2... of heat which can be passed on in this manner is performed in column 2 and column 3 of Table 3. It is initially assumed that the heat input from external utilities is zero. This is represented in Table 3 by a zero input to the top interval. Having...

  5. Experimental Research on Solar Assisted Heat Pump Heating System with Latent Heat Storage 

    E-Print Network [OSTI]

    Han, Z.; Zheng, M.; Liu, W.; Wang, F.

    2006-01-01T23:59:59.000Z

    Assisted Heat Pump Heating System with Latent Heat Storage. In this system, solar energy is the major heat source for a heat pump, and the supplementary heat source is soil. The disagreement in time between the space heat load and heat collected by solar...

  6. A Coupled AtmosphereOcean Radiative Transfer System Using the Analytic Four-Stream Approximation

    E-Print Network [OSTI]

    Liou, K. N.

    of the ocean. Shortwave radiation from the sun contributes most of the heat fluxes that penetrate the airA Coupled Atmosphere­Ocean Radiative Transfer System Using the Analytic Four-Stream Approximation WEI-LIANG LEE AND K. N. LIOU Department of Atmospheric and Oceanic Sciences, University of California

  7. Surface-induced heating of cold polar molecules

    E-Print Network [OSTI]

    Stefan Yoshi Buhmann; M. R. Tarbutt; Stefan Scheel; E. A. Hinds

    2009-12-14T23:59:59.000Z

    We study the rotational and vibrational heating of diatomic molecules placed near a surface at finite temperature on the basis of macroscopic quantum electrodynamics. The internal molecular evolution is governed by transition rates that depend on both temperature and position. Analytical and numerical methods are used to investigate the heating of several relevant molecules near various surfaces. We determine the critical distances at which the surface itself becomes the dominant source of heating and we investigate the transition between the long-range and short-range behaviour of the heating rates. A simple formula is presented that can be used to estimate the surface-induced heating rates of other molecules of interest. We also consider how the heating depends on the thickness and composition of the surface.

  8. Control system for fluid heated steam generator

    DOE Patents [OSTI]

    Boland, James F. (Bonneville County, ID); Koenig, John F. (Idaho Falls, ID)

    1985-01-01T23:59:59.000Z

    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.

  9. Control system for fluid heated steam generator

    DOE Patents [OSTI]

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

    1984-05-29T23:59:59.000Z

    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.

  10. Heating Cooling Flows with Weak Shock Waves

    E-Print Network [OSTI]

    W. G. Mathews; A. Faltenbacher; F. Brighenti

    2005-11-05T23:59:59.000Z

    The discovery of extended, approximately spherical weak shock waves in the hot intercluster gas in Perseus and Virgo has precipitated the notion that these waves may be the primary heating process that explains why so little gas cools to low temperatures. This type of heating has received additional support from recent gasdynamical models. We show here that outward propagating, dissipating waves deposit most of their energy near the center of the cluster atmosphere. Consequently, if the gas is heated by (intermittent) weak shocks for several Gyrs, the gas within 30-50 kpc is heated to temperatures that far exceed observed values. This heating can be avoided if dissipating shocks are sufficiently infrequent or weak so as not to be the primary source of global heating. Local PV and viscous heating associated with newly formed X-ray cavities are likely to be small, which is consistent with the low gas temperatures generally observed near the centers of groups and clusters where the cavities are located.

  11. Dynamics of heat transfer between nano systems

    E-Print Network [OSTI]

    Svend-Age Biehs; Girish S. Agarwal

    2012-10-18T23:59:59.000Z

    We develop a dynamical theory of heat transfer between two nano systems. In particular, we consider the resonant heat transfer between two nanoparticles due to the coupling of localized surface modes having a finite spectral width. We model the coupled nanosystem by two coupled quantum mechanical oscillators, each interacting with its own heat bath, and obtain a master equation for the dynamics of heat transfer. The damping rates in the master equation are related to the lifetimes of localized plasmons in the nanoparticles. We study the dynamics towards the steady state and establish connection with the standard theory of heat transfer in steady state. For strongly coupled nano particles we predict Rabi oscillations in the mean occupation number of surface plasmons in each nano particle.

  12. Uncertainty in the Oceanic Heat and Carbon Uptake and Their Impact on Climate Projections

    E-Print Network [OSTI]

    . These disagreements are, in part, due to differences in the rate of the penetration of heat into the deep ocean. SinceUncertainty in the Oceanic Heat and Carbon Uptake and Their Impact on Climate Projections Andrei P in the rate of heat and carbon uptake by the deep ocean on climate response to increases in greenhouse gas

  13. Evaporation and Condensation Heat Transfer Performance of Flammable Refrigerants in a

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    Evaporation and Condensation Heat Transfer Performance of Flammable Refrigerants in a Brazed Plate and Condensation Heat Transfer Performance of Flammable Refrigerants in a Brazed Plate Heat Exchanger Sheila C ........................................................... 8 3. Average relative difference (%) in calculated heat transfer rates for refrigerants and HTF

  14. Subsurface heaters with low sulfidation rates

    DOE Patents [OSTI]

    John, Randy Carl; Vinegar, Harold J

    2013-12-10T23:59:59.000Z

    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.

  15. 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)

    2006-05-16T23:59:59.000Z

    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.

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

    DOE Patents [OSTI]

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

    2003-09-09T23:59:59.000Z

    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.

  17. HEATING 7. 1 user's manual

    SciTech Connect (OSTI)

    Childs, K.W.

    1991-07-01T23:59:59.000Z

    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.

  18. RADIATIVE HEATING OF THE SOLAR CORONA

    SciTech Connect (OSTI)

    Moran, Thomas G., E-mail: moran@grace.nascom.nasa.gov [Physics Department, Catholic University of America, 200 Hannan Hall, Washington, DC 20064 (United States) and NASA/GSFC, Code 671, Greenbelt, MD 20771 (United States)

    2011-10-20T23:59:59.000Z

    We investigate the effect of solar visible and infrared radiation on electrons in the Sun's atmosphere using a Monte Carlo simulation of the wave-particle interaction and conclude that sunlight provides at least 40% and possibly all of the power required to heat the corona, with the exception of dense magnetic flux loops. The simulation uses a radiation waveform comprising 100 frequency components spanning the solar blackbody spectrum. Coronal electrons are heated in a stochastic manner by low coherence solar electromagnetic radiation. The wave 'coherence time' and 'coherence volume' for each component is determined from optical theory. The low coherence of solar radiation allows moving electrons to gain energy from the chaotic wave field which imparts multiple random velocity 'kicks' to these particles causing their velocity distribution to broaden or heat. Monte Carlo simulations of broadband solar radiative heating on ensembles of 1000 electrons show heating at per particle levels of 4.0 x 10{sup -21} to 4.0 x 10{sup -20} W, as compared with non-loop radiative loss rates of {approx}1 x 10{sup -20} W per electron. Since radiative losses comprise nearly all of the power losses in the corona, sunlight alone can explain the elevated temperatures in this region. The volume electron heating rate is proportional to density, and protons are assumed to be heated either by plasma waves or through collisions with electrons.

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

    SciTech Connect (OSTI)

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

    2013-05-01T23:59:59.000Z

    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.

  20. Modern hot water district heating

    SciTech Connect (OSTI)

    Karnitz, M.A.; Barnes, M.H.; Kadrmas, C.; Nyman, H.O.

    1984-06-01T23:59:59.000Z

    The history of district heating in Europe is drastically different from that in the United States. The development of district heating in northern and eastern Europe started in the early 1950s. Hot water rather than steam was used as the transport medium and the systems have proven to be more economical. Recently, the northern European concept has been introduced into two US cities - St. Paul and Willmar, Minnesota. The hot water project in St. Paul started construction and operation in the summer and fall of 1983, respectively. The entire first phase of the St. Paul project will take two summers to construct and will connect approximately 80 buildings for a total of 150 MW(t). The system spans the entire St. Paul business district and includes privately owned offices and retail buildings, city and county government buildings, hospitals, the state Capitol complex, and several industrial customers. The City of Willmar, Minnesota, replaced an old steam system with a modern hot water system in the summer of 1982. The first phase of the hot water system was constructed in the central business district. The system serves a peak thermal load of about 10 MW(t) and includes about 12,000 ft of network. The Willmar system completed the second stage of development in the fall of 1983. These two new systems demonstrate the benefits of the low-temperature hot water district heating technology. The systems are economical to build, have high reliability, and have low maintenance and operating cost.

  1. Finite element approximation of coupled seismic and ...

    E-Print Network [OSTI]

    zyserman

    layer, having a thickness of about 10 nm. Finite element approximation of coupled seismic and electromagnetic waves in gas hydrate-bearing sediments – p.

  2. Optimization Online - Equivalence of an Approximate Linear ...

    E-Print Network [OSTI]

    Alejandro Toriello

    2013-02-07T23:59:59.000Z

    Feb 7, 2013 ... Equivalence of an Approximate Linear Programming Bound with the Held-Karp Bound for the Traveling Salesman Problem. Alejandro Toriello ...

  3. Optimization Online - Probabilistic optimization via approximate p ...

    E-Print Network [OSTI]

    W. van vAckooij

    2015-05-27T23:59:59.000Z

    May 27, 2015 ... Probabilistic optimization via approximate p-efficient points and bundle methods. W. van vAckooij(wim.van-ackooij ***at*** edf.fr )

  4. Successive Convex Approximations to Cardinality-Constrained ...

    E-Print Network [OSTI]

    2012-04-16T23:59:59.000Z

    Replacing the ?0-norm (car- dinality) constraint in (P) by the above DC approximation ?(x, t), we obtain the following quadratic program with a DC constraint: (Pt).

  5. Approximations by Orthonormal Mapped Chebyshev Functions for ...

    E-Print Network [OSTI]

    2014-03-12T23:59:59.000Z

    a School of Mathematical Science, Xiamen University, 361005 Xiamen, China .... suitable mapping can be used to approximate functions on the whole line R (cf.

  6. Section 2.5: Approximations Using Increments

    E-Print Network [OSTI]

    2014-04-05T23:59:59.000Z

    Feb 26, 2014 ... Lesson 19. Definition. Examples. In this lesson we will discuss a method for approximating the value of a function at a specified point.

  7. HEATING6 verification

    SciTech Connect (OSTI)

    Bryan, C.B.; Childs, K.W.; Giles, G.E.

    1986-12-01T23:59:59.000Z

    The HEATING series of general purpose, finite-difference, conduction heat transfer codes have been in use for many years. During this time the codes have been used extensively, and a general confidence has been developed in regard to their accuracy. However, there has never been a formal verification in a published, citable document. This report documents just such a verification study for the latest code in the HEATING series, HEATING6. This study confirms that HEATING6 is capable of producing accurate results for a large class of heat transfer problems. 11 refs., 170 figs., 82 tabs.

  8. Heat Pump for High School Heat Recovery

    E-Print Network [OSTI]

    Huang, K.; Wang, H.; Zhou, X.

    2006-01-01T23:59:59.000Z

    ) [3] Yayun FAN. Experimental study on a heat pump technology in solar thermal utilization[J]. Acta Energiae Solaris Sinica, Oct.,2002; Vol.23,No.5 ? 581-585.(In Chinese) [4] Nengxi JIANG. Air-conditioning Heat Pump Technology and Its Applications...

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

    Broader source: Energy.gov [DOE]

    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...

  10. Photovoltaic roof heat flux

    E-Print Network [OSTI]

    Samady, Mezhgan Frishta

    2011-01-01T23:59:59.000Z

    designs (relatively) Photovoltaic Solar P a n e l AtmosphereCALIFORNIA, SAN DIEGO Photovoltaic Roof Heat Flux A ThesisABSTRACT OF T H E THESIS Photovoltaic Roof Heat Flux by

  11. DistrictHeating Nuevasaladecalderasydistribucin

    E-Print Network [OSTI]

    Fraguela, Basilio B.

    DistrictHeating Nuevasaladecalderasydistribución decaloreneláreauniversitariade AZapateira Jesús, difusión. DISTRICT HEATING O CALEFACCIÓN DE BARRIO #12;MATERIALIZACIÓN INTEGRACIÓN VISUAL DE ELEMENTOS rendimiento global de la instalación. - Contabilización de pérdidas en tuberías de distribución. #12;DISTRICT

  12. HEAT TRANSFER FLUIDS

    E-Print Network [OSTI]

    Lenert, Andrej

    2012-01-01T23:59:59.000Z

    The choice of heat transfer fluids has significant effects on the performance, cost, and reliability of solar thermal systems. In this chapter, we evaluate existing heat transfer fluids such as oils and molten salts based ...

  13. Neutron behavior, reactor control, and reactor heat transfer. Volume four

    SciTech Connect (OSTI)

    Not Available

    1986-01-01T23:59:59.000Z

    Volume four covers neutron behavior (neutron absorption, how big are nuclei, neutron slowing down, neutron losses, the self-sustaining reactor), reactor control (what is controlled in a reactor, controlling neutron population, is it easy to control a reactor, range of reactor control, what happens when the fuel burns up, controlling a PWR, controlling a BWR, inherent safety of reactors), and reactor heat transfer (heat generation in a nuclear reactor, how is heat removed from a reactor core, heat transfer rate, heat transfer properties of the reactor coolant).

  14. Magnetars as cooling neutron stars with internal heating

    E-Print Network [OSTI]

    A. D. Kaminker; D. G. Yakovlev; A. Y. Potekhin; N. Shibazaki; P. S. Shternin; O. Y. Gnedin

    2006-05-18T23:59:59.000Z

    We study thermal structure and evolution of magnetars as cooling neutron stars with a phenomenological heat source in a spherical internal layer. We explore the location of this layer as well as the heating rate that could explain high observable thermal luminosities of magnetars and would be consistent with the energy budget of neutron stars. We conclude that the heat source should be located in an outer magnetar's crust, at densities rho heat intensity of the order of 1e20 erg/s/cm^3. Otherwise the heat energy is mainly emitted by neutrinos and cannot warm up the surface.

  15. A climatic heat budget study of the Gulf of Mexico

    E-Print Network [OSTI]

    Etter, Paul Courtney

    1975-01-01T23:59:59.000Z

    of heat storage (G ) is calo~ lated apparently for the first time directly by use of available bathythermograph (BT) data. Heat flux di rergence due to currents (0 ), calculated as a residual in the heat budget equation, is small. The monthly mean... surface ( CA) . . 16 C. The rate of heat storage (Q ) 32 0. Solution of the oceanic heat budget 39 Comparison with Earlier Studies Summary 56 References Appendix A App ndix 3 Vita 61 79 vi LIST OF TA. '3LES Table Page Number of observations...

  16. On the design of heat-transfer probes

    SciTech Connect (OSTI)

    Brich, M.A.; Ganzha, V.L.; Saxena, S.C. [Univ. of Illinois, Chicago, IL (United States)] [Univ. of Illinois, Chicago, IL (United States)

    1997-03-01T23:59:59.000Z

    Saxena and coworkers have reported heat-transfer coefficient values for magnetofluidized beds using electrically heated heat-transfer probes. Here, a two-dimensional heat-transfer model is employed to investigate the influence of significant design features on measured parameters. Numerical calculations reveal that the thermal conductivity of the probe material has an insignificant contribution but the material of end caps and relative sizes and locations of the probe and heater appreciably influence the heat-transfer rates through end-conduction.

  17. Blood Management Using Approximate Linear Programming

    E-Print Network [OSTI]

    Shenoy, Prashant

    Blood Management Using Approximate Linear Programming Marek Petrik and Shlomo Zilberstein January 13th, 2009 Marek Petrik and Shlomo Zilberstein () Blood Management Using Approximate Linear ProgrammingJanuary 13th, 2009 1 / 36 #12;Blood Inventory Management Problem Regional blood banks: Aggregate

  18. 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.

  19. Abrasion resistant heat pipe

    DOE Patents [OSTI]

    Ernst, Donald M. (Leola, PA)

    1984-10-23T23:59:59.000Z

    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.

  20. Solar heat receiver

    DOE Patents [OSTI]

    Hunt, Arlon J. (Oakland, CA); Hansen, Leif J. (Berkeley, CA); Evans, David B. (Orinda, CA)

    1985-01-01T23:59:59.000Z

    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.

  1. Solar heat receiver

    DOE Patents [OSTI]

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

    1982-09-29T23:59:59.000Z

    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.

  2. Industrial Waste Heat Recovery

    E-Print Network [OSTI]

    Ward, M. E.; Solomon, N. G.; Tabb, E. S.

    1980-01-01T23:59:59.000Z

    INDUSTRIAL WASTE HEAT RECOVREY M. E. Ward and N. G. Solomon E. S. Tabb Solar Turbines International and Gas Research Institute San Diego, California Chicago, Illinois ABSTRACT i I One hundred fifty reports were reviewed along with interviews... tests, promising low temperature heat exchanger tube alloys and coated surfaces were identified. 1INTROUCTION of advanced technology heat recovery techniques 1_ Recovering waste heat from the flue gases of the pr~ary objective. Specific objectives...

  3. A corrosive resistant heat exchanger

    DOE Patents [OSTI]

    Richlen, S.L.

    1987-08-10T23:59:59.000Z

    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.

  4. Approximate error conjugation gradient minimization methods

    DOE Patents [OSTI]

    Kallman, Jeffrey S

    2013-05-21T23:59:59.000Z

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

    SciTech Connect (OSTI)

    Not Available

    1982-06-30T23:59:59.000Z

    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)

  6. Impingement cooling and heat transfer measurement using transient liquid crystal technique

    E-Print Network [OSTI]

    Huang, Yizhe

    1996-01-01T23:59:59.000Z

    A heat transfer study on jet impingement cooling is presented. The study focuses on the effect of impingement jet flow rate, jet angle, and flow exit direction on various target surface heat transfer distributions. A two-channel test section...

  7. ASSESSMENT OF COMBINED HEAT AND POWER SYSTEM "PREMIUM POWER" APPLICATIONS IN CALIFORNIA

    E-Print Network [OSTI]

    Norwood, Zack

    2010-01-01T23:59:59.000Z

    Cooling Heat and Power (CCHP) systems are being installed atand heating loads. These CCHP systems can also act as backupgenerators. In all cases the CCHP systems are rated at a

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

    SciTech Connect (OSTI)

    Duignan, M.R.; Greene, G.A. [Brookhaven National Lab., Upton, NY (United States); Irvine, T.F., Jr. [State Univ. of New York, Stony Brook, NY (United States). Dept. of Mechanical Engineering

    1992-04-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Duignan, M.R.; Greene, G.A. (Brookhaven National Lab., Upton, NY (United States)); Irvine, T.F., Jr. (State Univ. of New York, Stony Brook, NY (United States). Dept. of Mechanical Engineering)

    1992-04-01T23:59:59.000Z

    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.

  10. Acoustic Heating Peter Ulmschneider

    E-Print Network [OSTI]

    Ulmschneider, Peter

    mechanisms. 1. The acoustic heating theory Only a few years after Edlen's (1941) discovery that the solar acoustic wave radiation- · b. field acoustic wave Figure 1. Panel a: Acoustic heating in late-type stars: effective temperature TeJ f, gravity g and mixing length parameter fr. Panel b: Acoustic heating in early

  11. Heat Transfer Guest Editorial

    E-Print Network [OSTI]

    Kandlikar, Satish

    Journal of Heat Transfer Guest Editorial We are indeed delighted in bringing out this special issue was showcased in diverse areas such as traditional heat and mass transfer, lab-on-chip, sensors, biomedical applica- tions, micromixers, fuel cells, and microdevices. Selected papers in the field of heat transfer

  12. Pioneering Heat Pump Project

    Broader source: Energy.gov [DOE]

    Project objectives: To install and monitor an innovative WaterFurnace geothermal system that is technologically advanced and evolving; To generate hot water heating from a heat pump that uses non-ozone depleting refrigerant CO2. To demonstrate the energy efficiency of this system ground source heat pump system.

  13. Liquid heat capacity lasers

    DOE Patents [OSTI]

    Comaskey, Brian J. (Walnut Creek, CA); Scheibner, Karl F. (Tracy, CA); Ault, Earl R. (Livermore, CA)

    2007-05-01T23:59:59.000Z

    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.

  14. Calculations of Heat-Capacities of Adsorbates

    E-Print Network [OSTI]

    LAWRENCE, WR; Allen, Roland E.

    1976-01-01T23:59:59.000Z

    PHYSICAL REVIEW B VOLUME 14, NUMBER 7 1 OCTOBER 1976 Calculations of heat capacities of adsorbates W. R. Lawrence and R. E. Allen Department of Physics, Texas A& M University, College Station, Texas 77843 (Received 2 September 1975) The phonon... the substrate has a perfect (100) surface and the adsorbate goes down as a solid monolayer in registry with the substrate. The quasiharmonic approximation was used, and the results for Ne adsorbates were considerably different from those obtained...

  15. On approximate controllability of generalized KdV solitons

    E-Print Network [OSTI]

    Claudio Muñoz

    2014-05-24T23:59:59.000Z

    We consider the approximate control of solitons in generalized Korteweg-de Vries equations. By introducing a suitable internal bilinear control on the equation, we prove that any soliton is locally null controllable, and moreover, any soliton can be accelerated to any particular positive velocity, after a suitable large amount of time. Precise estimates on the error terms and the rate of decay in the approximate null controllability result are also given. Our method introduces a new insight on the control of nonlinear objects, from the point of view of interaction and collision problems for nonlinear dispersive equations, recently developed by Y. Martel and F. Merle. It can be applied in principle, to several other models with soliton solutions.

  16. On the Peterlin approximation for turbulent flows of polymer solutions

    E-Print Network [OSTI]

    Dario Vincenzi; Prasad Perlekar; Luca Biferale; Federico Toschi

    2015-05-26T23:59:59.000Z

    We study the impact of the Peterlin approximation on the statistics of the end-to-end separation of poly- mers in a turbulent flow. The FENE and FENE-P models are numerically integrated along a large number of Lagrangian trajectories resulting from a direct numerical simulation of three-dimensional homogeneous isotropic turbulence. Although the FENE-P model yields results in qualitative agreement with those of the FENE model, quantitative differences emerge. The steady-state probability of large extensions is overesti- mated by the FENE-P model. The alignment of polymers with the eigenvectors of the rate-of-strain tensor and with the direction of vorticity is weaker when the Peterlin approximation is used. At large Weissenberg numbers, both the correlation times of the extension and of the orientation of polymers are underestimated by the FENE-P model.

  17. On the Peterlin approximation for turbulent flows of polymer solutions

    E-Print Network [OSTI]

    Vincenzi, Dario; Biferale, Luca; Toschi, Federico

    2015-01-01T23:59:59.000Z

    We study the impact of the Peterlin approximation on the statistics of the end-to-end separation of poly- mers in a turbulent flow. The FENE and FENE-P models are numerically integrated along a large number of Lagrangian trajectories resulting from a direct numerical simulation of three-dimensional homogeneous isotropic turbulence. Although the FENE-P model yields results in qualitative agreement with those of the FENE model, quantitative differences emerge. The steady-state probability of large extensions is overesti- mated by the FENE-P model. The alignment of polymers with the eigenvectors of the rate-of-strain tensor and with the direction of vorticity is weaker when the Peterlin approximation is used. At large Weissenberg numbers, both the correlation times of the extension and of the orientation of polymers are underestimated by the FENE-P model.

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

    DOE Patents [OSTI]

    Meisner, Gregory P

    2013-10-08T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Xing, Lu [Oklahoma State University; Cullin, James [Oklahoma State University; Spitler, Jeffery [Oklahoma State University; Im, Piljae [ORNL; Fisher, Daniel [Oklahoma State University

    2011-01-01T23:59:59.000Z

    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.

  20. ARM - Evaluation Product - Broadband Heating Rate Profile Project (BBHRP)

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006Datastreamstwrcam40m Documentation DataDatastreamsxsaprhsrhi1-min (NAVBE1M) Value AddedProductsBroadband

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

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our Instagram Secretary900 SpecialNanoparticulateEmissions

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

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our Instagram Secretary Moniz is TakingDepartmentSensitivities of SCMs

  3. Thermal stability of a spherical shell heated by convection and cooled by boiling

    E-Print Network [OSTI]

    Qaim-Maqami, Hassan

    1973-01-01T23:59:59.000Z

    such high heat transfer rates by forced convection would require extremely high veloc- ities with subsequent high pressure dropsy With nuclee, boiling, however, such high heat transfe. rates an be obtained at much smaller velocities. Boiling heat...THERMAL STABILITY OF A. SPHERICAL SHELL HEATED BY CONVECTION AND COOLED BY BOILING A Thesis HASSAN @AIM-MAQAMI Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement for the degree of MASTER...

  4. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, Gershon (Oak Ridge, TN); Perez-Blanco, Horacio (Knoxville, TN)

    1984-01-01T23:59:59.000Z

    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.

  5. Applied heat transfer

    SciTech Connect (OSTI)

    Ganapathy, V.

    1982-01-01T23:59:59.000Z

    Heat transfer principles are discussed with emphasis on the practical aspects of the problems. Correlations for heat transfer and pressure drop from several worldwide sources for flow inside and outside of tubes, including finned tubes are presented, along with design and performance calculations of heat exchangers economizers, air heaters, condensers, waste-heat boilers, fired heaters, superheaters, and boiler furnaces. Vibration analysis for tube bundles and heat exchangers are also discussed, as are estimating gas-mixture properties at atmospheric and elevated pressures and life-cycle costing techniques. (JMT)

  6. Enhanced geothermal systems (EGS) with CO2 as heat transmission fluid--A scheme for combining recovery of renewable energy with geologic storage of CO2

    E-Print Network [OSTI]

    Pruess, K.

    2010-01-01T23:59:59.000Z

    effects on heat extraction rates and the water content ofof heat extraction for CO 2 and water- based systems, we hadover water-based systems, including larger heat extraction

  7. Coal home heating and environmental tobacco smoke in relation to lower respiratory illness in Czech children, from birth to 3 years of age

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    still com- monly used in home heating and smoking rates arefound exposure to coal home heating and ETS increase youngChildren’s Health Coal Home Heating and Environmental

  8. Transient Heat Transfer in TCAP Coils

    SciTech Connect (OSTI)

    Steimke, J.L.

    1999-03-09T23:59:59.000Z

    The Thermal Cycling Absorption Process (TCAP) is used to separate isotopes of hydrogen. TCAP involves passing a stream of mixed hydrogen isotopes through palladium deposited on kieselguhr (Pd/k) while cycling the temperature of the Pd/k. Kieselguhr is a silica mineral also called diatomite. To aid in the design of a full scale facility, the Thermal Fluids Laboratory was used by the Chemical and Hydrogen Technology Section to compare the heat transfer properties of three different configurations of stainless steel coils containing kieselguhr and helium. Testing of coils containing Pd/k and hydrogen isotopes would have been more prototypical but would have been too expensive. Three stainless steel coils filled with kieselguhr were tested; one made from 2.0 inch diameter tubing, one made from 2.0 inch diameter tubing with foam copper embedded in the kieselguhr and one made from 1.25 inch diameter tubing. It was known prior to testing that increasing the tubing diameter from 1.25 inch to 2.0 inch would slow the rate of temperature change. The primary purpose of the testing was to measure to what extent the presence of copper foam in a 2.0" tubing coil would compensate for the effect of larger diameter. Each coil was connected to a pressure gage and the coil was evacuated and backfilled with helium gas. Helium was used instead of a mixture of hydrogen isotopes for reasons of safety. Each coil was quickly immersed in a stirred bath of ethylene glycol at a temperature of approximately 100 degrees Celsius. The coil pressure increased, reflecting the increase in average temperature of its contents. The pressure transient was recored as a function of time after immersion. Because of the actual process will use Pd/k instead of kieselguhr, additional tests were run to determine the differences in thermal properties between the two materials. The method was to position a thermocouple at the center of a hollow sphere and pack the sphere with Pd/k. The sphere was sealed, quickly submerged in a bath of boiling water and the temperature transient was recorded. There sphere was then opened, the Pd/k was replaced with kieselguhr and the transient was repeated. The response was a factor of 1.4 faster for Pd/k than for kieselguhr, implying a thermal diffusivity approximately 40 percent higher than for kieselguhr. Another implication is that the transient tests with the coils would have proceeded faster if the coils had been filled with Pd/k rather than kieselguhr.

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

    SciTech Connect (OSTI)

    Shen, Bo [ORNL] [ORNL; Abdelaziz, Omar [ORNL] [ORNL; Rice, C Keith [ORNL] [ORNL

    2014-01-01T23:59:59.000Z

    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.

  10. Wave-mechanics and the adhesion approximation

    E-Print Network [OSTI]

    C. J. Short; P. Coles

    2006-11-22T23:59:59.000Z

    The dynamical equations describing the evolution of a self-gravitating fluid of cold dark matter (CDM) can be written in the form of a Schrodinger equation coupled to a Poisson equation describing Newtonian gravity. It has recently been shown that, in the quasi-linear regime, the Schrodinger equation can be reduced to the exactly solvable free-particle Schrodinger equation. The free-particle Schrodinger equation forms the basis of a new approximation scheme -the free-particle approximation - that is capable of evolving cosmological density perturbations into the quasi-linear regime. The free-particle approximation is essentially an alternative to the adhesion model in which the artificial viscosity term in Burgers' equation is replaced by a non-linear term known as the quantum pressure. Simple one-dimensional tests of the free-particle method have yielded encouraging results. In this paper we comprehensively test the free-particle approximation in a more cosmologically relevant scenario by appealing to an N-body simulation. We compare our results with those obtained from two established methods: the linearized fluid approach and the Zeldovich approximation. We find that the free-particle approximation comprehensively out-performs both of these approximation schemes in all tests carried out and thus provides another useful analytical tool for studying structure formation on cosmological scales.

  11. Heat pump apparatus

    DOE Patents [OSTI]

    Nelson, Paul A. (Wheaton, IL); Horowitz, Jeffrey S. (Woodridge, IL)

    1983-01-01T23:59:59.000Z

    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.

  12. Anisotropic turbulent model for solar coronal heating

    E-Print Network [OSTI]

    B. Bigot; S. Galtier; H. Politano

    2008-08-26T23:59:59.000Z

    Context : We present a self-consistent model of solar coronal heating, originally developed by Heyvaert & Priest (1992), in which we include the dynamical effect of the background magnetic field along a coronal structure by using exact results from wave MHD turbulence (Galtier et al. 2000). Aims : We evaluate the heating rate and the microturbulent velocity for comparison with observations in the quiet corona, active regions and also coronal holes. Methods :The coronal structures are assumed to be in a turbulent state maintained by the slow erratic motions of the magnetic footpoints. A description for the large-scale and the unresolved small-scale dynamics are given separately. From the latter, we compute exactly (or numerically for coronal holes) turbulent viscosites that are finally used in the former to close self-consistently the system and derive the heating flux expression. Results : We show that the heating rate and the turbulent velocity compare favorably with coronal observations. Conclusions : Although the Alfven wave turbulence regime is strongly anisotropic, and could reduce a priori the heating efficiency, it provides an unexpected satisfactory model of coronal heating for both magnetic loops and open magnetic field lines.

  13. Active microchannel heat exchanger

    DOE Patents [OSTI]

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

    2001-01-01T23:59:59.000Z

    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.

  14. Experimental Study of RF Pulsed Heating

    SciTech Connect (OSTI)

    Laurent, Lisa; Tantawi, Sami; Dolgashev, Valery; Nantista, Christopher; /SLAC; Higashi, Yasuo; /KEK, Tsukuba; Aicheler, Markus; Heikkinen, Samuli; Wuensch, Walter; /CERN

    2011-11-04T23:59:59.000Z

    Cyclic thermal stresses produced by rf pulsed heating can be the limiting factor on the attainable reliable gradients for room temperature linear accelerators. This is especially true for structures that have complicated features for wakefield damping. These limits could be pushed higher by using special types of copper, copper alloys, or other conducting metals in constructing partial or complete accelerator structures. Here we present an experimental study aimed at determining the potential of these materials for tolerating cyclic thermal fatigue due to rf magnetic fields. A special cavity that has no electric field on the surface was employed in these studies. The cavity shape concentrates the magnetic field on one flat surface where the test material is placed. The materials tested in this study have included oxygen free electronic grade copper, copper zirconium, copper chromium, hot isostatically pressed copper, single crystal copper, electroplated copper, Glidcop(reg. sign), copper silver, and silver plated copper. The samples were exposed to different machining and heat treatment processes prior to rf processing. Each sample was tested to a peak pulsed heating temperature of approximately 110 C and remained at this temperature for approximately 10 x 10{sup 6} rf pulses. In general, the results showed the possibility of pushing the gradient limits due to pulsed heating fatigue by the use of copper zirconium and copper chromium alloys.

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

    SciTech Connect (OSTI)

    Mittereder, N.; Poerschke, A.

    2013-11-01T23:59:59.000Z

    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.

  16. HEATING7.3. 1,2, or 3-d Heat Conduction Program

    SciTech Connect (OSTI)

    Childs, K.W. [Oak Ridge National Lab, TN (United States)

    1998-05-01T23:59:59.000Z

    HEATING7.2I and 7.3 is the most recent developmant in a series of heat-transfer codes and obsoletes all previous versions. HEATING can solve steady-state and/or transient heat conduction problems in one, two, or three-dimensional Cartesian, cylindrical coordinates 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 can be anisotropic. Materials may undergo a 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 graybody radiation problems may be modeled with user-defined factors for radiant exchange. The mesh spacing may be variable along each axis. HEATING uses a run time memory allocation scheme to avoid having to recompile to match memory requirements for each specific problem. HEATING utilizes free-form input.

  17. Power Generation From Waste Heat Using Organic Rankine Cycle Systems

    E-Print Network [OSTI]

    Prasad, A.

    1980-01-01T23:59:59.000Z

    universal bottoming cycle that can convert the energy in waste heat streams into usable shaft power. The nominal rating of the unit is 600 KWe or 900 SHP. The basic bottoming cycle concept is shown in Figure I. GAS TURBINE -, Y. DIESEL PROCESS HEAT... in Figure 2. The diverter valve directs the waste heat stream through the vaporizer. The working fluid is boiled and slightly superheated in the vaporizer. The superheated vapor expands through the turbine, generating mechanical power. This expansion...

  18. Optimization of Multibody Systems using Approximation Concepts

    E-Print Network [OSTI]

    Etman, L.F. Pascal

    UNIVERSITEIT EINDHOVEN Optimization of multibody systems using approximation concepts / Lodewijk Franciscus Pascal Etman. - Eindhoven : Technische Universiteit Eindhoven, 1997. - XVIII, 140 p. - With ref concepts / crashworthiness design / vehicle suspension Druk: Universiteitsdrukkerij TU Eindhoven Support

  19. Hardness of approximation for quantum problems

    E-Print Network [OSTI]

    Sevag Gharibian; Julia Kempe

    2012-09-05T23:59:59.000Z

    The polynomial hierarchy plays a central role in classical complexity theory. Here, we define a quantum generalization of the polynomial hierarchy, and initiate its study. We show that not only are there natural complete problems for the second level of this quantum hierarchy, but that these problems are in fact hard to approximate. Using these techniques, we also obtain hardness of approximation for the class QCMA. Our approach is based on the use of dispersers, and is inspired by the classical results of Umans regarding hardness of approximation for the second level of the classical polynomial hierarchy [Umans, FOCS 1999]. The problems for which we prove hardness of approximation for include, among others, a quantum version of the Succinct Set Cover problem, and a variant of the local Hamiltonian problem with hybrid classical-quantum ground states.

  20. Approximation algorithms for QMA-complete problems

    E-Print Network [OSTI]

    Sevag Gharibian; Julia Kempe

    2011-01-20T23:59:59.000Z

    Approximation algorithms for classical constraint satisfaction problems are one of the main research areas in theoretical computer science. Here we define a natural approximation version of the QMA-complete local Hamiltonian problem and initiate its study. We present two main results. The first shows that a non-trivial approximation ratio can be obtained in the class NP using product states. The second result (which builds on the first one), gives a polynomial time (classical) algorithm providing a similar approximation ratio for dense instances of the problem. The latter result is based on an adaptation of the "exhaustive sampling method" by Arora et al. [J. Comp. Sys. Sci. 58, p.193 (1999)] to the quantum setting, and might be of independent interest.

  1. Optimization Online - An Approximation Algorithm for Constructing ...

    E-Print Network [OSTI]

    Artur Pessoa

    2006-09-02T23:59:59.000Z

    Sep 2, 2006 ... In this paper, we propose an approximation algorithm for the 2-bit Hamming prefix code problem. Our algorithm spends $O(n \\log^3 n)$ time to ...

  2. RESTRICTED-TRACE APPROXIMATION FOR NUCLEAR ANTIFERROMAGNETISM

    E-Print Network [OSTI]

    Boyer, Edmond

    1353 RESTRICTED-TRACE APPROXIMATION FOR NUCLEAR ANTIFERROMAGNETISM M. GOLDMAN and G. SARMA Service to predict several properties of nuclear antiferromagnetic structures : sublattice magnetization of nuclear dipolar magnetic ordering, either antiferromagnetic or ferromagnetic, has been reported

  3. Approximate Bivariate Factorization, a Geometric Andre Galligo

    E-Print Network [OSTI]

    Hoeij, Mark van

    INRIA) Laboratoire de Mathematiques Parc Valrose 06108 Nice cedex 02, France galligo@unice.fr Mark van, Maple Code 1. INTRODUCTION 1.1 Approximate algebra Over the past ten years symbolic-numeric algorithms

  4. Optimization in Geometric Graphs: Complexity and Approximation

    E-Print Network [OSTI]

    Kahruman-Anderoglu, Sera

    2011-02-22T23:59:59.000Z

    We consider several related problems arising in geometric graphs. In particular, we investigate the computational complexity and approximability properties of several optimization problems in unit ball graphs and develop algorithms to find exact...

  5. Polymer state approximations of Schroedinger wave functions

    E-Print Network [OSTI]

    Klaus Fredenhagen; Felix Reszewski

    2006-08-25T23:59:59.000Z

    It is shown how states of a quantum mechanical particle in the Schroedinger representation can be approximated by states in the so-called polymer representation. The result may shed some light on the semiclassical limit of loop quantum gravity.

  6. A fresh look at the adhesion approximation

    E-Print Network [OSTI]

    Thomas Buchert

    1997-11-04T23:59:59.000Z

    I report on a systematic derivation of the phenomenological ``adhesion approximation'' from gravitational instability together with a brief evaluation of the related status of analytical modeling of large-scale structure.

  7. Linear source approximation in CASMO5

    SciTech Connect (OSTI)

    Ferrer, R.; Rhodes, J. [Studsvik Scandpower, Inc., 504 Shoup Ave., Idaho Falls, ID 83402 (United States); Smith, K. [Dept. of Nuclear Science and Engineering, Massachusetts Inst. of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States)

    2012-07-01T23:59:59.000Z

    A Linear Source (LS) approximation has been implemented in the two-dimensional Method of Characteristics (MOC) transport solver in a prototype version of CASMO5. The LS approximation, which relies on the computation of trajectory-based spatial moments over source regions to obtain the linear source expansion coefficients, improves the solution accuracy relative to the 'flat' or constant source approximation. In addition, the LS formulation is capable of treating arbitrarily-shaped source regions and is compatible with standard Coarse-Mesh Finite Difference (CMFD) acceleration. Numerical tests presented in this paper for the C5G7 MOX benchmark show that, for comparable accuracy with respect to the reference solution, the LS approximation can reduce the run time by a factor of four and the memory requirements by a factor often relative to the FS scheme. (authors)

  8. Approximate inference in Gaussian graphical models

    E-Print Network [OSTI]

    Malioutov, Dmitry M., 1981-

    2008-01-01T23:59:59.000Z

    The focus of this thesis is approximate inference in Gaussian graphical models. A graphical model is a family of probability distributions in which the structure of interactions among the random variables is captured by a ...

  9. Harmonic Wavelet Transform and Image Approximation

    E-Print Network [OSTI]

    Zhang, Zhihua; Saito, Naoki

    2010-01-01T23:59:59.000Z

    DOI 10.1007/s10851-010-0202-x Harmonic Wavelet Transform andwe approximate f by a harmonic function u such that thebanks. We call this the Harmonic Wavelet Transform (HWT).

  10. Radiative heat transfer in 2D Dirac materials

    E-Print Network [OSTI]

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

    2015-02-02T23:59:59.000Z

    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. Finally, we discuss the limitations to the validity of this scaling law imposed by spatial dispersion in 2D Dirac materials.

  11. Policies supporting Heat Pump Technologies

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    Policies supporting Heat Pump Technologies in Canada IEA Heat Pump Workshop London, UK November 13 in the world, with an average of 16,995 kilowatt-hours per annum. #12;Canada's Context for Heat Pumps Impacts avenues: Ground source heat pumps for cold climates (heating and cooling) Reversible air source heat

  12. Pulse*Star Inertial Confinement Fusion Reactor: heat transfer loop and balance of plant considerations

    SciTech Connect (OSTI)

    McDowell, M.W.; Murray, K.A.

    1984-05-09T23:59:59.000Z

    A conceptual heat transfer loop and balance of plant design for the Pulse*Star Inertial Confinement Fusion Reactor has been investigated and results are presented. The Pulse*Star reaction vessel, a perforated steel bell jar approximately 11 m in diameter, is immersed in Li/sub 17/Pb/sub 83/ coolant which flows through the perforations and forms a 1.5 m thick plenum of droplets around an 8 m diameter inner chamber. The reactor and associated pumps, piping, and steam generators are contained within a 17 m diameter pool of Li/sub 17/Pb/sub 83/ coolant to minimize structural requirements and occupied space, resulting in reduced cost. Four parallel heat transfer loops with flow rates of 5.5 m/sup 3//s each are necessary to transfer 3300 MWt of power. The steam generator design was optimized by finding the most cost-effective combination of heat exchanger area and pumping power. Power balance calculations based on an improved electrical conversion efficiency revealed a net electrical output of 1260 MWe to the bus bar and a resulting net efficiency of 39%. Suggested balance-of-plant layouts are also presented.

  13. Demonstration, testing, & evaluation of in situ heating of soil. Draft final report, Volume I

    SciTech Connect (OSTI)

    Dev, H.; Enk, J.; Jones, D.; Saboto, W.

    1996-02-12T23:59:59.000Z

    This document is a draft final report (Volume 1) for US DOE contract entitled, {open_quotes}Demonstration Testing and Evaluation of In Situ Soil Heating,{close_quotes} Contract No. DE-AC05-93OR22160, IITRI Project No. C06787. This report is presented in two volumes. Volume I contains the technical report and Volume II contains appendices with background information and data. In this project approximately 300 cu. yd. of clayey soil containing a low concentration plume of volatile organic chemicals was heated in situ by the application of electrical energy. It was shown that as a result of heating the effective permeability of soil to air flow was increased such that in situ soil vapor extraction could be performed. The initial permeability of soil was so low that the soil gas flow rate was immeasurably small even at high vacuum levels. When scaled up, this process can be used for the environmental clean up and restoration of DOE sites contaminated with VOCs and other organic chemicals boiling up to 120{degrees} to 130{degrees}C in the vadose zone. Although it may applied to many types of soil formations, it is particularly attractive for low permeability clayey soil where conventional in situ venting techniques are limited by low air flow.

  14. 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.

    1984-01-03T23:59:59.000Z

    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.

  15. Process for heating coal-oil slurries

    DOE Patents [OSTI]

    Braunlin, Walter A. (Spring, TX); Gorski, Alan (Lovington, NM); Jaehnig, Leo J. (New Orleans, LA); Moskal, Clifford J. (Oklahoma City, OK); Naylor, Joseph D. (Houston, TX); Parimi, Krishnia (Allison Park, PA); Ward, John V. (Arvada, CO)

    1984-01-03T23:59:59.000Z

    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.

  16. Condensing Heat Exchangers Optimize Steam Boilers

    E-Print Network [OSTI]

    Sullivan, B.; Sullivan, P. A.

    1983-01-01T23:59:59.000Z

    the flue gas from the p~oducts of combustion faom natural gas from 300 to the dew point of 129 results in an efficiency increase of 3%. Further cooling, resulting in condensa tion of water vapor, increases the rate of heat recovery dramatically and a...

  17. Transient queueing approximations for computer networks

    E-Print Network [OSTI]

    Baker, William A.

    1986-01-01T23:59:59.000Z

    for just the mean. Rothkopf/Oren's and Chang/Wang's methods obtained mean and variance values, and Clark's method produced several quantities which were used to find mean and variance statistics. For the M/M/1 case, the approximations by Gark and Chang... were very ac- curate over a wide range of input patterns and initial conditions. Rothkopf's was accurate over sll conditions but never as accurate as Chang or Clark. Johnston's and Rider's approximations performed acceptably only over some...

  18. Optimization of Heat Exchangers

    SciTech Connect (OSTI)

    Ivan Catton

    2010-10-01T23:59:59.000Z

    The objective of this research is to develop tools to design and optimize heat exchangers (HE) and compact heat exchangers (CHE) for intermediate loop heat transport systems found in the very high temperature reator (VHTR) and other Generation IV designs by addressing heat transfer surface augmentation and conjugate modeling. To optimize heat exchanger, a fast running model must be created that will allow for multiple designs to be compared quickly. To model a heat exchanger, volume averaging theory, VAT, is used. VAT allows for the conservation of mass, momentum and energy to be solved for point by point in a 3 dimensional computer model of a heat exchanger. The end product of this project is a computer code that can predict an optimal configuration for a heat exchanger given only a few constraints (input fluids, size, cost, etc.). As VAT computer code can be used to model characteristics )pumping power, temperatures, and cost) of heat exchangers more quickly than traditional CFD or experiment, optimization of every geometric parameter simultaneously can be made. Using design of experiment, DOE and genetric algorithms, GE, to optimize the results of the computer code will improve heat exchanger disign.

  19. Heat pump system

    DOE Patents [OSTI]

    Swenson, Paul F.; Moore, Paul B.

    1983-06-21T23:59:59.000Z

    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.

  20. Heat pump system

    DOE Patents [OSTI]

    Swenson, Paul F. (Shaker Heights, OH); Moore, Paul B. (Fedhaven, FL)

    1983-01-01T23:59:59.000Z

    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.

  1. 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.

  2. Chlorite Dissolution Rates

    SciTech Connect (OSTI)

    Carroll, Susan

    2013-07-01T23:59:59.000Z

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

  3. The Interest Rate Conundrum

    E-Print Network [OSTI]

    Craine, Roger; Martin, Vance L.

    2009-01-01T23:59:59.000Z

    Flows and US Interest Rates,” NBER Working Paper No 12560. [Working Paper # 2008 -03 The Interest Rate Conundrum Roger

  4. Fluidized bed heat treating system

    DOE Patents [OSTI]

    Ripley, Edward B; Pfennigwerth, Glenn L

    2014-05-06T23:59:59.000Z

    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.

  5. Summer HeatSummer Heat Heat stress solutions

    E-Print Network [OSTI]

    Liskiewicz, Maciej

    occur (then drink a lightly salted beverage like a sports drink). The water's temperature should be cool How should gardeners avoid becoming a safety threat to themselves and others when it's hot? Start to the heat. Become a weather watcher. Set up a small weather station (with a high/low thermom eter, rain

  6. Long term prediction of far-field heat conduction

    SciTech Connect (OSTI)

    Nassersharif, B.; Ma, L. [Univ. of Nevada, Las Vegas, NV (United States)

    1996-12-01T23:59:59.000Z

    A three dimensional numerical conduction only heat transfer model was developed to predict repository rock temperatures under the assumption of completely isolated burial. Sensitivity analyses were performed on the values of the thermal properties of the rock medium. Results indicate that rock temperatures at a distance of 100 m from the center of the repository peak at approximately 3000 years. A dry zone was established extending to approximately 80 times the volume of the repository after 10,000 years.

  7. Working on new gas turbine cycle for heat pump drive

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    Working on new gas turbine cycle for heat pump drive FILE COPY TAP By Irwin Stambler, Field Editor DO NOT 16 0 REMOVE 16 Small recuperated gas turbine engine, design rated at 13 hp and 27% efficiency of the cycle- as a heat pump drive for commercial installations. Company is testing prototype gas turbine

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

    Broader source: Energy.gov [DOE]

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

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

    Broader source: Energy.gov [DOE]

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

  10. Oscillating side-branch enhancements of thermoacoustic heat exchangers

    DOE Patents [OSTI]

    Swift, Gregory W.

    2003-05-13T23:59:59.000Z

    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.

  11. Water-heating dehumidifier

    DOE Patents [OSTI]

    Tomlinson, John J. (Knoxville, TN)

    2006-04-18T23:59:59.000Z

    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.

  12. Gas, Heat, Water, Sewerage Collection and Disposal, and Street Railway Companies (South Carolina)

    Broader source: Energy.gov [DOE]

    This legislation applies to public utilities and entities furnishing natural gas, heat, water, sewerage, and street railway services to the public. The legislation addresses rates and services,...

  13. Cooling Flows or Heating Flows?

    E-Print Network [OSTI]

    James Binney

    2003-10-08T23:59:59.000Z

    It is now clear that AGN heat cooling flows, largely by driving winds. The winds may contain a relativistic component that generates powerful synchrotron radiation, but it is not clear that all winds do so. The spatial and temporal stability of the AGN/cooling flow interaction are discussed. Collimation of the winds probably provides spatial stability. Temporal stability may be possible only for black holes with masses above a critical value. Both the failure of cooling flows to have adiabatic cores and the existence of X-ray cavities confirm the importance of collimated outflows. I quantify the scale of the convective flow that the AGN Hydra would need to drive if it balanced radiative inward flow by outward flow parallel to the jets. At least in Virgo any such flow must be confined to r<~20 kpc. Hydrodynamical simulations suggest that AGN outbursts cannot last longer than ~25 Myr. Data for four clusters with well studied X-ray cavities suggests that heating associated with cavity formation approximately balances radiative cooling. The role of cosmic infall and the mechanism of filament formation are briefly touched on.

  14. Heat storage duration

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1981-01-01T23:59:59.000Z

    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.

  15. Review of International Methods of Test to Rate the Efficiency of Water Heaters

    E-Print Network [OSTI]

    Lutz, Jim

    2012-01-01T23:59:59.000Z

    Energy factor (EF) rating Recovery Recovery efficiency Standby Standby heat loss coefficient Startup No energy Wasted No water European Union No Australia/

  16. HEATS: Thermal Energy Storage

    SciTech Connect (OSTI)

    None

    2012-01-01T23:59:59.000Z

    HEATS Project: The 15 projects that make up ARPA-E’s 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.

  17. Heat and mass exchanger

    DOE Patents [OSTI]

    Lowenstein, Andrew (Princeton, NJ); Sibilia, Marc J. (Princeton, NJ); Miller, Jeffrey A. (Hopewell, NJ); Tonon, Thomas (Princeton, NJ)

    2007-09-18T23:59:59.000Z

    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.

  18. Heat and mass exchanger

    DOE Patents [OSTI]

    Lowenstein, Andrew (Princeton, NJ); Sibilia, Marc J. (Princeton, NJ); Miller, Jeffrey A. (Hopewell, NJ); Tonon, Thomas (Princeton, NJ)

    2011-06-28T23:59:59.000Z

    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.

  19. Waste Heat Recovery

    Office of Environmental Management (EM)

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

  20. Passive solar space heating

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1980-01-01T23:59:59.000Z

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

  1. Heat rejection system

    DOE Patents [OSTI]

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

    1980-01-01T23:59:59.000Z

    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.

  2. 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

    2003-04-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Mathur, Anoop [Terrafore Inc.] [Terrafore Inc.

    2013-08-14T23:59:59.000Z

    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 experimentation.

  4. Comparison of Heating Methods for In-Situ Oil Shale Extraction 

    E-Print Network [OSTI]

    Hazra, Kaushik Gaurav

    2014-04-29T23:59:59.000Z

    Oil shales are lamellar, non-porous, impermeable hydrocarbon bearing rocks that contain organic matter called kerogen which, when heated at pyrolysis temperature of approximately 600-800 ?, thermo-chemically decomposes to liberate hydrocarbons...

  5. Comparison of Heating Methods for In-Situ Oil Shale Extraction

    E-Print Network [OSTI]

    Hazra, Kaushik Gaurav

    2014-04-29T23:59:59.000Z

    Oil shales are lamellar, non-porous, impermeable hydrocarbon bearing rocks that contain organic matter called kerogen which, when heated at pyrolysis temperature of approximately 600-800 ?, thermo-chemically decomposes to liberate hydrocarbons...

  6. Capture of Heat Energy from Diesel Engine Exhaust

    SciTech Connect (OSTI)

    Chuen-Sen Lin

    2008-12-31T23:59:59.000Z

    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, the synthetic fuel contained slightly less heat energy and fewer emissions. Test results obtained from adding different levels of a small amount of hydrogen into the intake manifold of a diesel-operated engine showed no effect on exhaust heat content. In other words, both synthetic fuel and conventional diesel with a small amount of hydrogen may not have a significant enough effect on the amount of recoverable heat and its feasibility. An economic analysis computer program was developed on Visual Basic for Application in Microsoft Excel. The program was developed to be user friendly, to accept different levels of input data, and to expand for other heat recovery applications (i.e., power, desalination, etc.) by adding into the program the simulation subroutines of the desired applications. The developed program has been validated using experimental data.

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

    SciTech Connect (OSTI)

    Elbel, Dr. Stefan W.; Petersen, Michael

    2013-04-25T23:59:59.000Z

    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.

  8. A generalized approximation for the thermophoretic force on a free-molecular particle.

    SciTech Connect (OSTI)

    Gallis, Michail A.; Rader, Daniel John; Torczynski, John Robert

    2003-07-01T23:59:59.000Z

    A general, approximate expression is described that can be used to predict the thermophoretic force on a free-molecular, motionless, spherical particle suspended in a quiescent gas with a temperature gradient. The thermophoretic force is equal to the product of an order-unity coefficient, the gas-phase translational heat flux, the particle cross-sectional area, and the inverse of the mean molecular speed. Numerical simulations are used to test the accuracy of this expression for monatomic gases, polyatomic gases, and mixtures thereof. Both continuum and noncontinuum conditions are examined; in particular, the effects of low pressure, wall proximity, and high heat flux are investigated. The direct simulation Monte Carlo (DSMC) method is used to calculate the local molecular velocity distribution, and the force-Green's-function method is used to calculate the thermophoretic force. The approximate expression is found to predict the calculated thermophoretic force to within 10% for all cases examined.

  9. Longitudinal variation of tides in the MLT region: 2. Relative effects of solar radiative and latent heating

    E-Print Network [OSTI]

    Forbes, Jeffrey

    of solar radiative and latent heating Xiaoli Zhang,1 Jeffrey M. Forbes,1 and Maura E. Hagan2 Received 11 study examines the relative importance of radiative heating and latent heating in accounting (GSWM) and new tidal heating rates derived from International Satellite Cloud Climatology Project (ISCCP

  10. IMPLEMENTING GROUND SOURCE HEAT PUMP AND GROUND LOOP HEAT EXCHANGER

    E-Print Network [OSTI]

    IMPLEMENTING GROUND SOURCE HEAT PUMP AND GROUND LOOP HEAT EXCHANGER MODELS IN THE ENERGYPLUS #12;ii IMPLEMENTING GROUND SOURCE HEAT PUMP AND GROUND LOOP HEAT EXCHANGER MODELS IN THE ENERGYPLUS............................................................... 2 1.3. Overview of the Parameter Estimation Water-to-Water Heat Pump Model ........... 5 1

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

    DOE Patents [OSTI]

    Polcyn, Adam D. (Pittsburgh, PA)

    2010-12-28T23:59:59.000Z

    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.

  12. First university owned district heating system using biomass heat

    E-Print Network [OSTI]

    Northern British Columbia, University of

    Highlights · First university owned district heating system using biomass heat · Capacity: 15 MMBtu Main Campus District Heating Performance · Avoided: 3500 tonnes of CO2 · Particulate: less than 10 mg District Heating Goals To displace 85% of natural gas used for core campus heating. Fuel Bunker Sawmill

  13. Longshore sediment transport rate calculated incorporating wave orbital velocity fluctuations

    E-Print Network [OSTI]

    Smith, Ernest Ray

    2006-10-30T23:59:59.000Z

    Laboratory experiments were performed to study and improve longshore sediment transport rate predictions. Measured total longshore transport in the laboratory was approximately three times greater for plunging breakers than spilling breakers. Three...

  14. Approximate Killing Fields as an Eigenvalue Problem

    E-Print Network [OSTI]

    Christopher Beetle

    2008-08-12T23:59:59.000Z

    Approximate Killing vector fields are expected to help define physically meaningful spins for non-symmetric black holes in general relativity. However, it is not obvious how such fields should be defined geometrically. This paper relates a definition suggested recently by Cook and Whiting to an older proposal by Matzner, which seems to have been overlooked in the recent literature. It also describes how to calculate approximate Killing fields based on these proposals using an efficient scheme that could be of immediate practical use in numerical relativity.

  15. Extending the Eikonal Approximation to Low Energy

    E-Print Network [OSTI]

    Pierre Capel; Tokuro Fukui; Kazuyuki Ogata

    2014-11-21T23:59:59.000Z

    E-CDCC and DEA, two eikonal-based reaction models are compared to CDCC at low energy (e.g. 20AMeV) to study their behaviour in the regime at which the eikonal approximation is supposed to fail. We confirm that these models lack the Coulomb deflection of the projectile by the target. We show that a hybrid model, built on the CDCC framework at low angular momenta and the eikonal approximation at larger angular momenta gives a perfect agreement with CDCC. An empirical shift in impact parameter can also be used reliably to simulate this missing Coulomb deflection.

  16. Realizing Physical Approximation of the Partial Transpose

    E-Print Network [OSTI]

    Hyang-Tag Lim; Yong-Su Kim; Young-Sik Ra; Joonwoo Bae; Yoon-Ho Kim

    2011-04-18T23:59:59.000Z

    The partial transpose by which a subsystem's quantum state is solely transposed is of unique importance in quantum information processing from both fundamental and practical point of view. In this work, we present a practical scheme to realize a physical approximation to the partial transpose using local measurements on individual quantum systems and classical communication. We then report its linear optical realization and show that the scheme works with no dependence on local basis of given quantum states. A proof-of-principle demonstration of entanglement detection using the physical approximation of the partial transpose is also reported.

  17. Approximate initial data for binary black holes

    E-Print Network [OSTI]

    Kenneth A. Dennison; Thomas W. Baumgarte; Harald P. Pfeiffer

    2006-08-26T23:59:59.000Z

    We construct approximate analytical solutions to the constraint equations of general relativity for binary black holes of arbitrary mass ratio in quasicircular orbit. We adopt the puncture method to solve the constraint equations in the transverse-traceless decomposition and consider perturbations of Schwarzschild black holes caused by boosts and the presence of a binary companion. A superposition of these two perturbations then yields approximate, but fully analytic binary black hole initial data that are accurate to first order in the inverse of the binary separation and the square of the black holes' momenta.

  18. Energy identity of approximate biharmonic maps to Riemannian manifolds and its application

    E-Print Network [OSTI]

    Wang, Changyou

    2011-01-01T23:59:59.000Z

    We consider in dimension four weakly convergent sequences of approximate biharmonic maps to a Riemannian manifold with bi-tension fields bounded in $L^p$ for $p>\\frac43$. We prove an energy identity that accounts for the loss of hessian energies by the sum of hessian energies over finitely many nontrivial biharmonic maps on $\\mathbb R^4$. As a corollary, we obtain an energy identity for the heat flow of biharmonic maps at time infinity.

  19. Microchannel heat sink assembly

    DOE Patents [OSTI]

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

    1992-03-24T23:59:59.000Z

    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.

  20. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard (2853-A Hickory Pl., Costa Mesa, CA 92626)

    1984-01-01T23:59:59.000Z

    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.

  1. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard (2853-A Hickory Pl., Costa Mesa, CA 92626)

    1984-01-01T23:59:59.000Z

    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.

  2. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard (2853-A Hickory Pl., Costa Mesa, CA 92626)

    1984-01-01T23:59:59.000Z

    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.

  3. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard (2853-A Hickory Pl., Costa Mesa, CA 92626)

    1981-01-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Brown, P.G. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

    1991-12-31T23:59:59.000Z

    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.

  5. Solar heating system

    DOE Patents [OSTI]

    Schreyer, James M. (Oak Ridge, TN); Dorsey, George F. (Concord, TN)

    1982-01-01T23:59:59.000Z

    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.

  6. Knudsen heat capacity

    SciTech Connect (OSTI)

    Babac, Gulru, E-mail: babac@itu.edu.tr [Institute of Energy, Istanbul Technical University, Istanbul 34469 (Turkey)] [Institute of Energy, Istanbul Technical University, Istanbul 34469 (Turkey); Reese, Jason M. [School of Engineering, University of Edinburgh, Edinburgh EH9 3JL (United Kingdom)] [School of Engineering, University of Edinburgh, Edinburgh EH9 3JL (United Kingdom)

    2014-05-15T23:59:59.000Z

    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.

  7. Improved solar heating systems

    DOE Patents [OSTI]

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

    1980-05-16T23:59:59.000Z

    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.

  8. Tushino - 3 district heating project/Moscow

    SciTech Connect (OSTI)

    Mayer, H.W.

    1995-09-01T23:59:59.000Z

    The contract for supply and installation of Honeywell control equipment at the district heating plant in Moscow suburb of Tushino was signed between the Mayor of Moscow and Honeywell in December 1991. Total contract value is US$3 million. The aim is to demonstrate on a pilot project the potential energy savings and improved pleat safety which can be achieved by means of electronic control of latest design. The Honeywell contract basically covers modernization of instrumentation and control of the gas fired heating plant, comprising water preparation and 4 boilers, of 100 Gcal/h each, i.e., 400 Gcal/h total. The plant is feeding the hot water network which has 60 heat exchanger stations connected. The heat exchangers (thermal rating between 2 to 10 Gcal/h each) supply hot water mainly to residential building blocks for apartment heating and domestic hot water. Honeywell`s responsibility covers engineering, supply of TDC 3000 micro-processor based control system for the boilers and DeltaNet Excel control for the Heat Exchangers. The contract also includes installation and start-up of the total control system.

  9. Residential gas heat pump assessment: A market-based approach

    SciTech Connect (OSTI)

    Hughes, P.J.

    1995-09-01T23:59:59.000Z

    There has been considerable activity in recent years to develop technologies that could reduce or levelize residential and light-commercial building space cooling electrical use and heating/cooling energy use. For example, variable or multi-speed electric heat pumps, electric ground-source heat pumps, dual-fuel heat pumps, multi-function heat pumps, and electric cool storage concepts have been developed; and several types of gas heat pumps are emerging. A residential gas heat pump (GHP) benefits assessment is performed to assist gas utility and equipment manufacturer decision making on level of commitment to this technology. The methodology and generic types of results that can be generated are described. National market share is estimated using a market segmentation approach. The assessment design requires dividing the 334 Metropolitan Statistical Areas (MSAS) of the US into 42 market segments of relatively homogeneous weather and gas/electric rates (14 climate groupings by 3 rate groupings). Gas and electric rates for each MSA are evaluated to arrive at population-weighted rates for the market segments. GHPs are competed against 14 conventional equipment options in each homogeneous segment.

  10. BCP Annual Rate Process

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

    2015 BCP Annual Rate Process (FY 2016 Base Charge & Rate) Informal Process Rate Activity Schedule (doc) Informal Customer Meeting Thursday March 11, 2015 at 10:30 A.M. Conf Rms 3&4...

  11. Heat Flow, Heat Transfer And Lithosphere Rheology In Geothermal...

    Open Energy Info (EERE)

    heat flow values as high as several watts per meter squared can be found. Systematic interpretation of heat flow patterns sheds light on heat transfer mechanisms at depth on...

  12. Blind Channel Equalization and -Approximation Algorithms

    E-Print Network [OSTI]

    Ye, Yinyu

    Blind Channel Equalization and #15;-Approximation Algorithms #3; Qingyu Li 1 , Er-Wei Bai 1 University of Iowa Iowa City, IA 52242 Abstract In this paper, we show that a blind equalizer can be obtained without using any sta- tistical information on the input by formulating the blind channel equalization

  13. FRACTAL APPROXIMATION AND COMPRESSION USING PROJECTED IFS

    E-Print Network [OSTI]

    Baskurt, Atilla

    FRACTAL APPROXIMATION AND COMPRESSION USING PROJECTED IFS �ric Guérin, �ric Tosan and Atilla, or images) with fractal models is an important center of interest for research. The general inverse problem.The most known of them is the fractal image compression method introduced by Jacquin. Generally speaking

  14. Approximate Inference and Protein-Folding

    E-Print Network [OSTI]

    Weiss, Yair

    Approximate Inference and Protein-Folding Chen Yanover and Yair Weiss School of Computer Science Side-chain prediction is an important subtask in the protein-folding problem. We show that #12;nding algorithms, including a widely used protein-folding software (SCWRL). 1 Introduction Inference in graphical

  15. APPROXIMATION ALGORITHMS FOR SCHEDULING a dissertation

    E-Print Network [OSTI]

    Chekuri, Chandra

    Approved for the University Committee on Graduate Studies: iii #12; iv #12; Abstract This thesis describes instance of the problem, returns a solution whose value is within some guaranteed multiplicative factor ff release dates only we obtain an e e\\Gamma1 ' 1:58 approximation. For the parallel machine case we obtain

  16. Symbolic Test Selection Based on Approximate Analysis

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Symbolic Test Selection Based on Approximate Analysis Bertrand Jeannet, Thierry J´eron, Vlad Rusu}@irisa.fr Abstract. This paper addresses the problem of generating symbolic test cases for testing the conformance. The challenge we consider is the selection of test cases according to a test purpose, which is here a set

  17. Approximating Power Indices --Theoretical and Empirical Analysis

    E-Print Network [OSTI]

    Rosenschein, Jeff

    , by providing lower bounds for both deter- ministic and randomized algorithms for calculating power indices. WeApproximating Power Indices -- Theoretical and Empirical Analysis Yoram Bachrach School and Computer Science, The Hebrew University, Jerusalem, Israel Amin Saberi Department of Management Science

  18. Kirchhoff approximation for diffusive waves Jorge Ripoll*

    E-Print Network [OSTI]

    Lorenzo, Jorge Ripoll

    Laboratoire d'Energetique Moleculaire et Macroscopique, Combustion, Ecole Centrale Paris, Centre National de for accurately solving the direct scattering problem 17,18,23 for arbitrary geometries, but these methods,26 . This approximation is a linear method that does not involve matrix inversion while solving the forward problem

  19. IMPROVING THE APPROXIMATION AND CONVERGENCE CAPABILITIES OF

    E-Print Network [OSTI]

    Yeung, Dit-Yan

    ­dimensional data. Projection pursuit learning (PPL) formulates PPR in a neural network framework. One major difference between PPR and PPL is that the smoothers in PPR are nonparametric, whereas those in PPL are based known, we demonstrate that PPL networks do not have the universal approximation and strong convergence

  20. Approximating Human Reaching Volumes Using Inverse Kinematics

    E-Print Network [OSTI]

    Rodríguez, Inmaculada

    of reach: standing reach, which is useful in computer animation where virtual humans have to interact. Introduction Virtual Humans are a valuable medium for gaining knowledge and understanding about the human bodyApproximating Human Reaching Volumes Using Inverse Kinematics I. Rodrígueza , M. Peinadoa , R

  1. Exact controllability of the superlinear heat equation 1 Statement of ...

    E-Print Network [OSTI]

    2008-05-11T23:59:59.000Z

    y Xr (0,T ;V')? C(1+ a ?)K [ F Lr (Lr (V) + y L2(H2)?C(H1)]. ... Assume p be a solution of (2.1) associated to p0 ? L2(?) and f ? L2(Q). ...... J.-P. Puel and E. Zuazua, Approximate controllability of the semilinear heat equation. Proc. Roy. Soc.

  2. Research Rate Liaison Rate for outside academic &

    E-Print Network [OSTI]

    Gilchrist, James F.

    as of 12/9/13 External Rate Spark Plasma Sintering ) Spark Plasma Sintering > 24 hrs 2 8 Vacuum Hot Press

  3. Economic Options for Upgrading Waste Heat 

    E-Print Network [OSTI]

    Erickson, D. C.

    1983-01-01T23:59:59.000Z

    There are at least six major types of equipment that upgrade waste heat: (1) thermocompressor; (2) electric drive compressor heat pump; (3) absorption heat pump; (4) high temperature heat powered compressor heat pump; (5) reverse absorption heat...

  4. Economic Options for Upgrading Waste Heat

    E-Print Network [OSTI]

    Erickson, D. C.

    1983-01-01T23:59:59.000Z

    There are at least six major types of equipment that upgrade waste heat: (1) thermocompressor; (2) electric drive compressor heat pump; (3) absorption heat pump; (4) high temperature heat powered compressor heat pump; (5) reverse absorption heat...

  5. Heat-Of-Reaction Chemical Heat Pumps--Possible Configurations

    E-Print Network [OSTI]

    Kirol, L. D.

    for water and gas connections, and temperature variations. Recent work on heat pump cycles using complex compound reactions includes development of energy storage systems at laboratories in Europe (11) and the United States (12), and residential...ABSTRACT Chemical heat pumps utilize working fluids which undergo reversible chemical changes. Mechanically driven reactive heat pump cycles or, alternatively, hl~a: driven heat pumps in which either heat engine or heat pump working fluid...

  6. 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...

  7. Effective Rate Period

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

    10012014 - 03312015 Mid-Year Change (if applicable) 10012014 - 09302015 Power Rates Annual Revenue Requirement Rate Schedule Power Revenue Requirement 70,091,227 CV-F13...

  8. Effective Rate Period

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

    of the FY Mid-Year Change 10012013 - 03312014 04012014 - 09302014 Power Rates Annual Revenue Requirement Rate Schedule Power Revenue Requirement 73,441,557...

  9. 2004 Rate Adjustments

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

    for Transmission and Ancillary Services Federal Register Notice -- Rate Order WAPA-141: Notice of Extension of Formula Rates for Transmission and Ancillary Services If you have any...

  10. WAPA-169 Rate Order

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

    69 Rate Order Western is proposing adjustments to the Salt Lake City Area Integrated Projects firm power rate and the Colorado River Storage Project Transmission and ancillary...

  11. Multiple System Rate Process

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

    DSW Multiple System Transmission Rate Process Federal Register Notice Withdrawing Rate Proposal (PDF) Formal Process Extension Federal Register Notice (PDF) Customer Savisngs Under...

  12. Condensation heat transfer in square, triangular, and semi-circular mini-channels Melanie Derby a

    E-Print Network [OSTI]

    Peles, Yoav

    , and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, United States b Department was the coolant. The heat transfer rate was obtained through a coolant-side energy balance. To obtain condensation. An energy balance on the fluid-to-fluid heat exchanger measured heat duty while sensors in two obstructed

  13. Eric Moulton, Ferri Hassani, Pejman Nekoovaght Microwave-Assisted Heating in Rock

    E-Print Network [OSTI]

    Barthelat, Francois

    Eric Moulton, Ferri Hassani, Pejman Nekoovaght Microwave-Assisted Heating in Rock INTRODUCTION to expensive replacements. Expansive heating through microwaves breaks up the rock, which reduces the stress the mechanisms and parameters governing the heating rate of a material. Department of Mining and Materials

  14. Heating of trapped ions from the quantum ground state Q. A. Turchette,*,

    E-Print Network [OSTI]

    Sackett, Cass

    Heating of trapped ions from the quantum ground state Q. A. Turchette,*, D. Kielpinski, B. E. King. Monroe, and D. J. Wineland Time and Frequency Division, National Institute of Standards and Technology heating of laser-cooled 9 Be ions held in radio-frequency Paul traps. We have measured heating rates

  15. Heat generation from electronics increases with the advent of high-density integrated circuit technology. To

    E-Print Network [OSTI]

    Boyer, Edmond

    circuit technology. To come up with the heat generation, microscale cooling has been thought as a promising technology. Prediction of heat transfer rate is crucial in design of microscale cooling device1 Abstract Heat generation from electronics increases with the advent of high-density integrated

  16. 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)

    1983-01-01T23:59:59.000Z

    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.

  17. 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)

    1982-01-01T23:59:59.000Z

    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.

  18. Calculation of Heating Values for the High Flux Isotope Reactor

    SciTech Connect (OSTI)

    Peterson, Joshua L [ORNL] [ORNL; Ilas, Germina [ORNL] [ORNL

    2012-01-01T23:59:59.000Z

    Calculating the amount of energy released by a fission reaction (fission Q value) and the heating rate distribution in a nuclear reactor is an important part of the safety analysis. However, these calculations can become very complex. One of the codes that can be used for this type of analyses is the Monte Carlo transport code MCNP5. Currently it is impossible to calculate the Q value and heating rate disposition for delayed beta and delayed gamma particles directly from MCNP5. The purpose of this paper is to outline a rigorous method for indirectly calculating the Q values and heating rates in the High Flux Isotope Reactor (HFIR), based on previous similar studies carried out for very high-temperature reactor configurations. This method has been applied in this study to calculate heating rates for the beginning of cycle (BOC) and end-of-cycle (EOC) states of HFIR. In addition, the BOC results obtained for HFIR are compared with corresponding results for the Advanced Test Reactor. The fission Q value for HFIR was calculated as 200.2 MeV for the BOC and 201.3 MeV for the EOC. It was also determined that 95.1% and 95.4% of the heat was deposited within the HFIR fuel plates for the BOC and EOC models, respectively. This methodology can also be used for heating rate calculations for HFIR experiments.

  19. A COMPARISON OF LABORATORY AND FIELD-TEST MEASUREMENTS OF HEAT PUMP WATER HEATERS

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    #12;A COMPARISON OF LABORATORY AND FIELD-TEST MEASUREMENTS OF HEAT PUMP WATER HEATERS William P a heat pump water heater (HPWH). After developing the HPWH, a field-test plan was implemented whereby 20 evaluate this effect. #12;INTRODUCTION Domestic water heaters account for approximately 2.5 EJ (2.4 x 1015

  20. Workshop on Condensing Heating and Water Heating Equipment

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

    Workshop on Condensing Heating and Water Heating Equipment Thursday, October 9, 2014 List of Attendees OrganizationAttendees DOE - John Cymbalsky - Ashley Armstrong - Johanna...

  1. City of Klamath Falls District Heating District Heating Low Temperatur...

    Open Energy Info (EERE)

    Geothermal Facility Jump to: navigation, search Name City of Klamath Falls District Heating District Heating Low Temperature Geothermal Facility Facility City of Klamath Falls...

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

    Energy Savers [EERE]

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

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

    SciTech Connect (OSTI)

    Hellinger, Petr [Astronomical Institute and Institute of Atmospheric Physics, AS CR Bocni II/1401, CZ-14131 Prague (Czech Republic)] [Astronomical Institute and Institute of Atmospheric Physics, AS CR Bocni II/1401, CZ-14131 Prague (Czech Republic); Passot, Thierry; Sulem, Pierre-Louis [Université de Nice Sophia Antipolis, CNRS, Observatoire de la Côte d'Azur, BP 4229, 06304 Nice Cedex 4 (France)] [Université de Nice Sophia Antipolis, CNRS, Observatoire de la Côte d'Azur, BP 4229, 06304 Nice Cedex 4 (France); Trávní?ek, Pavel M. [Astronomical Institute and Institute of Atmospheric Physics, AS CR Bocni II/1401, CZ-14131 Prague (Czech Republic) [Astronomical Institute and Institute of Atmospheric Physics, AS CR Bocni II/1401, CZ-14131 Prague (Czech Republic); Space Sciences Laboratory, University of Berkeley, 7 Gauss Way, Berkeley, California 94720 (United States)

    2013-12-15T23:59:59.000Z

    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.

  4. Proceedings: Heat exchanger workshop

    SciTech Connect (OSTI)

    Not Available

    1987-07-01T23:59:59.000Z

    Heat transfer processes are of controlling importance in the operation of a thermal power plant. Heat exchangers are major cost items and are an important source of problems causing poor power plant availability and performance. A workshop to examine the improvements that can be made to heat exchangers was sponsored by the Electric Power Research Institute (EPRI) on June 10-11, 1986, in Palo Alto, California. This workshop was attended by 25 engineers and scientists representing EPRI-member utilities and EPRI consultants. A forum was provided for discussions related to the design, operation and maintenance of utility heat transfer equipment. The specific objectives were to identify research directions that could significantly improve heat exchanger performance, reliability and life cycle economics. Since there is a great diversity of utility heat transfer equipment in use, this workshop addressed two equipment categories: Boiler Feedwater Heaters (FWH) and Heat Recovery Steam Generators (HRSG). The workshop was divided into the following panel sessions: functional design, mechanical design, operation, suggested research topics, and prioritization. Each panel session began with short presentations by experts on the subject and followed by discussions by the attendees. This report documents the proceedings of the workshop and contains recommendations of potentially valuable areas of research and development. 4 figs.

  5. Micro heat barrier

    DOE Patents [OSTI]

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

    2003-08-12T23:59:59.000Z

    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.

  6. Integrating preconcentrator heat controller

    DOE Patents [OSTI]

    Bouchier, Francis A. (Albuquerque, NM); Arakaki, Lester H. (Edgewood, NM); Varley, Eric S. (Albuquerque, NM)

    2007-10-16T23:59:59.000Z

    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.

  7. Heat Balance Analysis to Validate the Heat Dissipation Rate of a Man-Made Lake as a Heat Rejection

    E-Print Network [OSTI]

    Song, L.; Hayes, T.; Dawson, M.

    2011-01-01T23:59:59.000Z

    Power plants were originally designed to use convenient bodies of water and cooling towers due to unavailability of these sources. Though the Environment Protection Agency (EPA) has been pushing regulation that requires all new generation created...

  8. Complex Compound Chemical Heat Pumps 

    E-Print Network [OSTI]

    Rockenfeller, U.; Langeliers, J.; Horn, G.

    1987-01-01T23:59:59.000Z

    Complex-compound solid-vapor fluid pairs can be used in heat of reaction heat pumps for temperature amplifier (TA) as well as heat amplifier (HA) cycle configurations. This report describes the conceptual hardware design for complex compound...

  9. 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 ...

  10. Complex Compound Chemical Heat Pumps

    E-Print Network [OSTI]

    Rockenfeller, U.; Langeliers, J.; Horn, G.

    Complex-compound solid-vapor fluid pairs can be used in heat of reaction heat pumps for temperature amplifier (TA) as well as heat amplifier (HA) cycle configurations. This report describes the conceptual hardware design for complex compound...

  11. Optimization of Heat Exchanger Cleaning 

    E-Print Network [OSTI]

    Siegell, J. H.

    1986-01-01T23:59:59.000Z

    The performance of heat integration systems is quantified in terms of the amount of heat that is recovered. This decreases with time due to increased fouling of the heat exchange surface. Using the "Total Fouling Related Expenses (TFRE)" approach...

  12. Comments on article 'symmetric heat and mass transfer in a rotating spherical layer,' JETP 94 (3), 459 (2002)

    SciTech Connect (OSTI)

    Alexandrov, D. V., E-mail: Dmitri.Alexandrov@usu.ru; Malygin, A. P. [Ural Federal University (Russian Federation)

    2012-02-15T23:59:59.000Z

    Analytic solutions to the heat and mass transfer equations, which were obtained in [1], are corrected. It is shown that the dependence of the growth rate of the Earth's inner core on heat flux changes in this case.

  13. Heat treatment furnace

    DOE Patents [OSTI]

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

    2014-10-21T23:59:59.000Z

    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.

  14. Molecular heat pump

    E-Print Network [OSTI]

    Dvira Segal; Abraham Nitzan

    2005-10-11T23:59:59.000Z

    We propose a novel molecular device that pumps heat against a thermal gradient. The system consists of a molecular element connecting two thermal reservoirs that are characterized by different spectral properties. The pumping action is achieved by applying an external force that periodically modulates molecular levels. This modulation affects periodic oscillations of the internal temperature of the molecule and the strength of its coupling to each reservoir resulting in a net heat flow in the desired direction. The heat flow is examined in the slow and fast modulation limits and for different modulation waveforms, thus making it possible to optimize the device performance.

  15. Specifying Waste Heat Boilers

    E-Print Network [OSTI]

    Ganapathy, V.

    or hydrochloric acid vapor should be mentioned upfront so the HRSG designer can take proper precauations while designing the unit.Material selection is also impacted by the presence of corrosive gases.If partial pressure of hydrogen is high in the gas stream...SPECIFYING WASTE HEAT BOILERS V.Ganapathy.ABCO Industries Abilene,Texas ABSTRACT Waste heat boilers or Heat Recovery Steam 'Generators(HRSGs) as they are often called are used to recover energy from waste gas streams in chemical plants...

  16. Simulation of Infrared Laser Heating of Silica Using Heat Conduction and Multifrequency Radiation Diffusion Equations Adapted for Homogeneous Refractive Lossy Media

    SciTech Connect (OSTI)

    Shestakov, A I; Matthews, M J; Vignes, R M; Stolken, J S

    2010-10-28T23:59:59.000Z

    Localized, transient heating of materials using micro-scale, highly absorbing laser light has been used in many industries to anneal, melt and ablate material with high precision. Accurate modeling of the relative contributions of conductive, convective and radiative losses as a function of laser parameters is essential to optimizing micro-scale laser processing of materials. In bulk semi-transparent materials such as silicate glass melts, radiation transport is known to play a significantly larger role as the temperature increases. Conventionally, radiation is treated in the frequency-averaged diffusive limit (Rosseland approximation). However, the role and proper treatment of radiative processes under rapidly heated, high thermal gradient conditions, often created through laser-matter interactions, is at present not clear. Starting from the radiation transport equation for homogeneous, refractive lossy media, they derive the corresponding time-dependent multi-frequency diffusion equations. Zeroth and first moments of the transport equation couple the energy density, flux and pressure tensor. The system is closed by neglecting the temporal derivative of the flux and replacing the pressure tensor by its diagonal analogue. The radiation equations are coupled to a diffusion equation for the matter temperature. They are interested in modeling infrared laser heating of silica over sub-millimeter length scales, and at possibly rapid rates. Hence, in contrast to related work, they retain the temporal derivative of the radiation field. They derive boundary conditions at a planar air-silica interface taking account of reflectivities obtained from the Fresnel relations that include absorption. The effect of a temperature-dependent absorption index is explored through construction of a multi-phonon dielectric function that includes mode dispersion. The spectral dimension is discretized into a finite number of intervals yielding a system of multigroup diffusion equations. Simulations are presented. To demonstrate the bulk heat loss due to radiation and the effect of the radiation's temporal derivative, they model cooling of a silica slab, initially at 2500 K, for 10 s. Retaining the derivative enables correctly modeling the loss of photons initially present in the slab. Other simulations model irradiating silica discs (of approximately 5 mm radii and thickness) with a CO2 laser: {lambda} = 10.59 and 4.6 um, Gaussian profile, r{sub 0} = 0.5 mm for 1/e decay. By surrounding the disks in room-temperature air, they make use of the boundary conditions described above.

  17. Asymptotic solution for heat convection-radiation equation

    SciTech Connect (OSTI)

    Mabood, Fazle; Ismail, Ahmad Izani Md [School of Mathematical Sciences, Universiti Sains Malaysia, 11800 USM, Penang (Malaysia); Khan, Waqar A. [Department of Engineering Sciences, National University of Sciences and Technology, PN Engineering College, Karachi, 75350 (Pakistan)

    2014-07-10T23:59:59.000Z

    In this paper, we employ a new approximate analytical method called the optimal homotopy asymptotic method (OHAM) to solve steady state heat transfer problem in slabs. The heat transfer problem is modeled using nonlinear two-point boundary value problem. Using OHAM, we obtained the approximate analytical solution for dimensionless temperature with different values of a parameter ?. Further, the OHAM results for dimensionless temperature have been presented graphically and in tabular form. Comparison has been provided with existing results from the use of homotopy perturbation method, perturbation method and numerical method. For numerical results, we used Runge-Kutta Fehlberg fourth-fifth order method. It was found that OHAM produces better approximate analytical solutions than those which are obtained by homotopy perturbation and perturbation methods, in the sense of closer agreement with results obtained from the use of Runge-Kutta Fehlberg fourth-fifth order method.

  18. Orthogonal Polynomial Approximation in Higher Dimensions: Applications in Astrodynamics

    E-Print Network [OSTI]

    Bani Younes, Ahmad H.

    2013-08-05T23:59:59.000Z

    harmonic series by a family of locally precise orthogonal polynomial approximations for efficient computation. A method is introduced which adapts the approximation degree radially, compatible with the truth that the highest degree approximations (to...

  19. VISCOSITY AND RELAXATION APPROXIMATIONS FOR HYPERBOLIC SYSTEMS OF CONSERVATION LAWS

    E-Print Network [OSTI]

    Tzavaras, Athanasios E.

    VISCOSITY AND RELAXATION APPROXIMATIONS FOR HYPERBOLIC SYSTEMS deal with the approximation of conservation * *laws via viscosity or relaxation. The following topics are covered: The general structure of viscosity and relaxation approximations is discu

  20. Radiative Heat Transfer between Neighboring Particles

    E-Print Network [OSTI]

    Alejandro Manjavacas; F. Javier Garcia de Abajo

    2012-01-26T23:59:59.000Z

    The near-field interaction between two neighboring particles is known to produce enhanced radiative heat transfer. We advance in the understanding of this phenomenon by including the full electromagnetic particle response, heat exchange with the environment, and important radiative corrections both in the distance dependence of the fields and in the particle absorption coefficients. We find that crossed terms of electric and magnetic interactions dominate the transfer rate between gold and SiC particles, whereas radiative corrections reduce it by several orders of magnitude even at small separations. Radiation away from the dimer can be strongly suppressed or enhanced at low and high temperatures, respectively. These effects must be taken into account for an accurate description of radiative heat transfer in nanostructured environments.

  1. Heat capacity at the glass transition

    E-Print Network [OSTI]

    Kostya Trachenko; Vadim Brazhkin

    2010-07-13T23:59:59.000Z

    A fundamental problem of glass transition is to explain the jump of heat capacity at the glass transition temperature $T_g$ without asserting the existence of a distinct solid glass phase. This problem is also common to other disordered systems, including spin glasses. We propose that if $T_g$ is defined as the temperature at which the liquid stops relaxing at the experimental time scale, the jump of heat capacity at $T_g$ follows as a necessary consequence due to the change of system's elastic, vibrational and thermal properties. In this picture, we discuss time-dependent effects of glass transition, and identify three distinct regimes of relaxation. Our approach explains widely observed logarithmic increase of $T_g$ with the quench rate and the correlation of heat capacity jump with liquid fragility.

  2. Value of solar thermal industrial process heat

    SciTech Connect (OSTI)

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

    1986-03-01T23:59:59.000Z

    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.

  3. Preliminary calculations on direct heating of a containment atmosphere by airborne core debris

    SciTech Connect (OSTI)

    Pilch, M.; Tarbell, W.W.

    1986-07-01T23:59:59.000Z

    Direct heating of the containment atmosphere by airborne core debris may be a significant source of containment pressurization in those accident sequences where the primary system is still at high pressure when the RPV fails. Vigorous blowdown of the primary system may result in nearly complete relocation of core debris out of the reactor cavity and possibly into the containment atmosphere where the liberation of thermal and chemical energy can directly heat the atmosphere. Rate independent and rate dependent models are developed and exercised parametrically to quantify the possible magnitude and rate of containment pressurization from direct heating. The possible mitigative effects of airborne water and subcompartment heating are also investigated.

  4. Experimental investigation of nucleate boiling heat transfer mechanisms for cylinders in water and FC-72

    SciTech Connect (OSTI)

    Ammerman, C.N.; You, S.M.; Hong, Y.S. [Univ. of Texas, Arlington, TX (United States). Dept. of Mechanical and Aerospace Engineering

    1995-12-31T23:59:59.000Z

    A recently developed photographic method is used to quantify vapor volumetric flow rate above a boiling wire. The volumetric flow rate is combined with additional analyses to determine the overall contributions to the total heat flux from four nucleate boiling heat transfer mechanisms (latent heat, natural convection, Marangoni flow, and micro-convection). This technique is used to quantify the boiling heat transfer mechanisms versus heat flux for a 510-{micro}m wire immersed in saturated water and in water with a small amount of liquid soap added. These data are compared with similar data taken for a 75-{micro}m wire boiling in saturated FC-72. For all cases, latent heat is the dominant heat transfer mechanism in the fully developed nucleate boiling regime. In addition, the latent heat component is significantly increased by the addition of small amounts of soap (surfactant).

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

    SciTech Connect (OSTI)

    Piyush Sabharwall; Mike Patterson; Vivek Utgikar; Fred Gunnerson

    2008-09-01T23:59:59.000Z

    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 heat exchanger with Na as the heat exchanger coolant. In order to design a very efficient and effective heat exchanger one must optimize the design such that we have a high heat transfer and a lower pressure drop, but there is always a trade-off between them. Based on NGNP operational parameters, a heat exchanger analysis with the sodium phase change will be presented to show that the heat exchanger has the potential for highly effective heat transfer, within a small volume at reasonable cost.

  6. Liquid Phase Heating Systems

    E-Print Network [OSTI]

    Mordt, E. H.

    1979-01-01T23:59:59.000Z

    Temperature Water (HTW) central district heating systems are far superior to steam systems in large, spread out installations such as airports, universities and office complexes. Water, pressurized to keep it in the liquid state, is distributed at 400o...

  7. Composite heat damage assessment

    SciTech Connect (OSTI)

    Janke, C.J.; Wachter, E.A. [Oak Ridge National Lab., TN (United States); Philpot, H.E. [Oak Ridge K-25 Site, TN (United States); Powell, G.L. [Oak Ridge Y-12 Plant, TN (United States)

    1993-12-31T23:59:59.000Z

    The effects of heat damage were determined on the residual mechanical, physical, and chemical properties of IM6/3501-6 laminates, and potential nondestructive techniques to detect and assess material heat damage were evaluated. About one thousand preconditioned specimens were exposed to elevated temperatures, then cooled to room temperature and tested in compression, flexure, interlaminar shear, shore-D hardness, weight loss, and change in thickness. Specimens experienced significant and irreversible reduction in their residual properties when exposed to temperatures exceeding the material upper service temperature of this material (350{degrees}F). The Diffuse Reflectance Infrared Fourier Transform and Laser-Pumped Fluorescence techniques were found to be capable of rapid, in-service, nondestructive detection and quantitation of heat damage in IM6/3501- 6. These techniques also have the potential applicability to detect and assess heat damage effects in other polymer matrix composites.

  8. Mechanical Compression Heat Pumps 

    E-Print Network [OSTI]

    Apaloo, T. L.; Kawamura, K.; Matsuda, J.

    1986-01-01T23:59:59.000Z

    to develop, design and test compressors built to meet the needs of the mechanically demanding industrial heat pump applications which often require high compression ratios and temperatures in excess of 200 degrees F. This paper will review the theoretical...

  9. Photovoltaic roof heat flux

    E-Print Network [OSTI]

    Samady, Mezhgan Frishta

    2011-01-01T23:59:59.000Z

    e l Atmosphere ceiling, back panel roof, exposed roof insideSAN DIEGO Photovoltaic Roof Heat Flux A Thesis submitted i no n Convection Exposed Roof Temperature Seasonal Temperature

  10. Photovoltaic roof heat flux

    E-Print Network [OSTI]

    Samady, Mezhgan Frishta

    2011-01-01T23:59:59.000Z

    under the offset unit's solar panel, the hf formula (16) wasdrop below the angle unit's solar panel at night time. D u rfor both the units, the solar panel covered roof was a heat

  11. Passive solar heating analysis

    SciTech Connect (OSTI)

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

    1984-01-01T23:59:59.000Z

    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.

  12. A numerical approximation to distribution function

    E-Print Network [OSTI]

    Tuttle, Keith Allan

    1977-01-01T23:59:59.000Z

    then is to approximate F(Y) numerically. We sub- divide the unit cube Q into N cubes eqch of length h I/N on a n n side. Within each individual subcube Q , we will define an affine approximation to f, W = g(x , . . . , x ), which requires the gradient of 1' ' 'n our... & h/2, k k i + 1/2 2 n k k = 1, 2, . . . , n]. Let f(x) f C [Q ] the space of twice continuously n differentiable functions on Q , and define the auxiliary function g(x) as the tangent to f at x. i + 1 2 for x f Q. . That is, if x I Q i (x) f (x1 2...

  13. Mechanical Compression Heat Pumps

    E-Print Network [OSTI]

    Apaloo, T. L.; Kawamura, K.; Matsuda, J.

    dampened because there is a current abundance of the basic sources of industrial energy (namely oil and natural gas). Meanwhile, Mycom used the window of the current opportunities to develop, design and test compressors built to meet the needs... requirements of the compressors which constitute the heart and soul of the system. It will also provide a quick survey of the available types of compressors for heat pumping and some of the industrial processes where simultaneous heating and cooling...

  14. Compressed Indexes for Approximate String Matching

    E-Print Network [OSTI]

    Sung, Wing-Kin Ken"

    Compressed Indexes for Approximate String Matching Ho-Leung Chan1 Tak-Wah Lam1, Wing-Kin Sung2 Siu the index space to O(n log n). Huynh et al. [10] and Lam et al. [11] further compressed the index to O,wongss}@comp.nus.edu.sg Abstract. We revisit the problem of indexing a string S[1..n] to support searching all substrings

  15. Approximating spheroid inductive responses using spheres

    SciTech Connect (OSTI)

    Smith, J. Torquil; Morrison, H. Frank

    2003-12-12T23:59:59.000Z

    The response of high permeability ({mu}{sub r} {ge} 50) conductive spheroids of moderate aspect ratios (0.25 to 4) to excitation by uniform magnetic fields in the axial or transverse directions is approximated by the response of spheres of appropriate diameters, of the same conductivity and permeability, with magnitude rescaled based on the differing volumes, D.C. magnetizations, and high frequency limit responses of the spheres and modeled spheroids.

  16. BLOCK DIAGONALLY DOMINANT POSITIVE DEFINITE APPROXIMATE FILTERS AND SMOOTHERS

    E-Print Network [OSTI]

    BLOCK DIAGONALLY DOMINANT POSITIVE DEFINITE APPROXIMATE FILTERS AND SMOOTHERS Running title: BLOCKÆciently small as to preclude the loss of positive de#12;niteness in the approximate equations. Therefore

  17. BLOCK DIAGONALLY DOMINANT POSITIVE DEFINITE APPROXIMATE FILTERS AND SMOOTHERS

    E-Print Network [OSTI]

    BLOCK DIAGONALLY DOMINANT POSITIVE DEFINITE APPROXIMATE FILTERS AND SMOOTHERS Running title: BLOCK the loss of positive definiteness in the approximate equations. Therefore previous analyses have

  18. Verified integrity properties for safe approximate program transformations

    E-Print Network [OSTI]

    Kim, Deokhwan

    Approximate computations (for example, video, audio, and image processing, machine learning, and many scientific computations) have the freedom to generate a range of acceptable results. Approximate program transformations ...

  19. System Modeling and Building Energy Simulations of Gas Engine Driven Heat Pump

    SciTech Connect (OSTI)

    Mahderekal, Isaac [Oak Ridge National Laboratory (ORNL); Vineyard, Edward [Oak Ridge National Laboratory (ORNL)

    2013-01-01T23:59:59.000Z

    To improve the system performance of a gas engine driven heat pump (GHP) system, an analytical modeling and experimental study has been made by using desiccant system in cooling operation (particularly in high humidity operations) and suction line waste heat recovery to augment heating capacity and efficiency. The performance of overall GHP system has been simulated with a detailed vapor compression heat pump system design model. The modeling includes: (1) GHP cycle without any performance improvements (suction liquid heat exchange and heat recovery) as a baseline (both in cooling and heating mode), (2) the GHP cycle in cooling mode with desiccant system regenerated by waste heat from engine incorporated, (3) GHP cycle in heating mode with heat recovery (recovered heat from engine). According to the system modeling results, by using the desiccant system the sensible heat ratio (SHR- sensible heat ratio) can be lowered to 40%. The waste heat of the gas engine can boost the space heating efficiency by 25% at rated operating conditions. In addtion,using EnergyPlus, building energy simulations have been conducted to assess annual energy consumptions of GHP in sixteen US cities, and the performances are compared to a baseline unit, which has a electrically-driven air conditioner with the seasonal COP of 4.1 for space cooling and a gas funace with 90% fuel efficiency for space heating.

  20. Intrinsically irreversible heat engine

    DOE Patents [OSTI]

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

    1984-01-01T23:59:59.000Z

    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.

  1. Intrinsically irreversible heat engine

    DOE Patents [OSTI]

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

    1984-12-25T23:59:59.000Z

    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.

  2. Intrinsically irreversible heat engine

    DOE Patents [OSTI]

    Wheatley, John C. (Los Alamos, NM); Swift, Gregory W. (Los Alamos, NM); Migliori, Albert (Santa Fe, NM)

    1984-01-01T23:59:59.000Z

    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.

  3. Convective heat flow probe

    DOE Patents [OSTI]

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

    1984-01-09T23:59:59.000Z

    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.

  4. Radial flow heat exchanger

    DOE Patents [OSTI]

    Valenzuela, Javier (Hanover, NH)

    2001-01-01T23:59:59.000Z

    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.

  5. Heat Transfer Research 44(1), 130 (2013) ENTROPY GENERATION ANALYSIS

    E-Print Network [OSTI]

    Zhang, Yuwen

    Heat Transfer Research 44(1), 1­30 (2013) ENTROPY GENERATION ANALYSIS FOR A PULSATING HEAT, m R gas constant of vapor, g gravity, m/s2 kJ/kgK h(hlsen, hlv) coefficient of convective heat Re, kg/m3 of left vapor plug, W p shear stress, N/m3 Qout,v1 condensation heat transfer rate Subscripts

  6. A Sample Approximation Approach for Optimization with ...

    E-Print Network [OSTI]

    2008-05-02T23:59:59.000Z

    which has m = 200 rows and n = 1000 columns. ..... Optimization of a continuous distillation process under random inflow rate. Comput. ... F. Dabbene, editors, Probabilistic and Randomized Methods for Design Under Uncertainty, pages 3–

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

    DOE Patents [OSTI]

    Koplow, Jeffrey P

    2013-12-10T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Solar air heating system for combined DHW and space heating solar air collector PV-panel fannon-return valve DHW tank mantle cold waterhot water roof Solar Energy Centre Denmark Danish Technological Institute SEC-R-29 #12;Solar air heating system for combined DHW and space heating Søren Østergaard Jensen

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

    DOE Patents [OSTI]

    Koplow, Jeffrey P. (San Ramon, CA)

    2012-07-24T23:59:59.000Z

    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. PERFORMANCE OF A STIRLING ENGINE POWERED HEAT ACTIVATED HEAT PUMP

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    PERFORMANCE OF A STIRLING ENGINE POWERED HEAT ACTIVATED HEAT PUMP W. D. C. Richards and W. L. Auxer) which employs a natural gas fired Stirling engine to drive a Rankine cycle vapor compressor is presently by the heat pump effect. The Stirling engine/Rankine cycle refrigeration loop heat pump being developed would

  11. Waste Heat Recovery Using a Circulating Heat Medium Loop

    E-Print Network [OSTI]

    Manning, E., Jr.

    1981-01-01T23:59:59.000Z

    by a circulating heat medium loop where waste heat is recovered for useful purposes. The heat medium chosen is turbine fuel. It is pumped around the refinery to pick up heat at the crude distilling unit, the hydrocracker, the catalytic cracker...

  12. A Note on Euler Approximations for Stochastic Differential Equations with Delay

    SciTech Connect (OSTI)

    Gyöngy, Istvan; Sabanis, Sotirios, E-mail: s.sabanis@ed.ac.uk [University of Edinburgh, Maxwell Institute for Mathematical Sciences and School of Mathematics (United Kingdom)

    2013-12-15T23:59:59.000Z

    An existence and uniqueness theorem for a class of stochastic delay differential equations is presented, and the convergence of Euler approximations for these equations is proved under general conditions. Moreover, the rate of almost sure convergence is obtained under local Lipschitz and also under monotonicity conditions.

  13. FINITE VOLUME APPROXIMATION OF THE EFFECTIVE DIFFUSION MATRIX: THE CASE OF INDEPENDENT BOND

    E-Print Network [OSTI]

    FINITE VOLUME APPROXIMATION OF THE EFFECTIVE DIFFUSION MATRIX: THE CASE OF INDEPENDENT BOND with independent jump rates across nearest neighbour bonds of the lattice. We show that the infinite volume effective diffusion matrix can be almost surely recovered as the limit of finite volume periodized effective

  14. Quasiparticle random phase approximation uncertainties and their correlations in the analysis of neutrinoless double beta decay

    E-Print Network [OSTI]

    Amand Faessler; G. L. Fogli; E. Lisi; V. Rodin; A. M. Rotunno; F. Simkovic

    2009-03-06T23:59:59.000Z

    The variances and covariances associated to the nuclear matrix elements (NME) of neutrinoless double beta decay are estimated within the quasiparticle random phase approximation (QRPA). It is shown that correlated NME uncertainties play an important role in the comparison of neutrinoless double beta decay rates for different nuclei, and that they are degenerate with the uncertainty in the reconstructed Majorana neutrino mass.

  15. Utilizing secondary heat to heat wash oil in the coke-oven gas desulfurization division

    SciTech Connect (OSTI)

    Volkov, E.L.

    1981-01-01T23:59:59.000Z

    Removal of hydrogen sulfide from the coke-oven gas by the vacuum-carbonate method involves significant energy costs, comprising about 47% of the total costs of the process. This is explained by the significant demand of steam for regeneration of the wash oil, the cost of which exceeds 30% of the total operating costs. The boiling point of the saturated wash oil under vacuum does not exceed 70/sup 0/C, thus the wash oil entering the regenerator can be heated either by the direct coke-oven gas or by the tar supernatant from the gas collection cycle. Utilizing the secondary heat of the direct coke-oven gas and the tar supernatant liquor (the thermal effect is approximately the same) to heat the wash oil from the gas desulfurization shops significantly improves the industrial economic indices. Heating the wash oil from gas desulfurization shops using the vacuum-carbonate method by the heat of the tar supernatant liquor may be adopted at a number of coking plants which have a scarcity of thermal resources and which have primary coolers with vertical tubes.

  16. Joule Heating and Anomalous Resistivity in the Solar Corona

    E-Print Network [OSTI]

    Steven R. Spangler

    2008-12-22T23:59:59.000Z

    Recent radioastronomical observations of Faraday rotation in the solar corona can be interpreted as evidence for coronal currents, with values as large as $2.5 \\times 10^9$ Amperes (Spangler 2007). These estimates of currents are used to develop a model for Joule heating in the corona. It is assumed that the currents are concentrated in thin current sheets, as suggested by theories of two dimensional magnetohydrodynamic turbulence. The Spitzer result for the resistivity is adopted as a lower limit to the true resistivity. The calculated volumetric heating rate is compared with an independent theoretical estimate by Cranmer et al (2007). This latter estimate accounts for the dynamic and thermodynamic properties of the corona at a heliocentric distance of several solar radii. Our calculated Joule heating rate is less than the Cranmer et al estimate by at least a factor of $3 \\times 10^5$. The currents inferred from the observations of Spangler (2007) are not relevant to coronal heating unless the true resistivity is enormously increased relative to the Spitzer value. However, the same model for turbulent current sheets used to calculate the heating rate also gives an electron drift speed which can be comparable to the electron thermal speed, and larger than the ion acoustic speed. It is therefore possible that the coronal current sheets are unstable to current-driven instabilities which produce high levels of waves, enhance the resistivity and thus the heating rate.

  17. The dynamic response of heated glass

    E-Print Network [OSTI]

    Sewall, Roy Edward

    1972-01-01T23:59:59.000Z

    rates of strain. This research was prompted, in part, by NASA studies on ductile-type craters in glassy lunar rocks. The dynamic response of Apollo spacecraft windows, made of fused silica, also led to this research. The investigation consists... Response of Heated Glass. (December 1972) Roy Edward Sewall, B. S. , Texas AS? University Directed by: Dr. James L. Rand The purpose of this research is to investigate the dynamic behavior of fused silica glass subjected to high temperatures and high...

  18. Oil production models with normal rate curves Dudley Stark

    E-Print Network [OSTI]

    Stark, Dudley

    Oil production models with normal rate curves Dudley Stark School of Mathematical Sciences Queen;Abstract The normal curve has been used to fit the rate of both world and U.S.A. oil production sizes are lognormally distributed, and the starting time of the production of a field is approximately

  19. Toolbox Safety Talk Heat Stress

    E-Print Network [OSTI]

    Pawlowski, Wojtek

    Toolbox Safety Talk Heat Stress Environmental Health & Safety Facilities Safety & Health Section for inducing heat stress. When the body is unable to cool itself by sweating, several heat-induced illnesses Stress · Know signs/symptoms of heat-related illnesses; monitor yourself and coworkers. · Block out

  20. temperature heat pumps applied to

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    losses (waste heat) 250-300°C......1100°C ~ 100 TWh/year Low temperature thermal losses (waste heat) 25°C;Waste heat recovery (1) In a decreasing energetic interest order Achema 2012 Frankfurt June 21th 2012>>Twaste #12;Waste heat recovery (2) Achema 2012 Frankfurt June 21th 2012 There is no interesting thermal

  1. Heat Transfer in Complex Fluids

    SciTech Connect (OSTI)

    Mehrdad Massoudi

    2012-01-01T23:59:59.000Z

    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 (linear) behavior for a given range of parameters or geometries; there are many empirical or semi-empirical constitutive equations suggested for these fluids. There have also been many non-linear constitutive relations which have been derived based on the techniques of continuum mechanics. The non-linearities oftentimes appear due to higher gradient terms or time derivatives. When thermal and or chemical effects are also important, the (coupled) momentum and energy equations can give rise to a variety of interesting problems, such as instability, for example the phenomenon of double-diffusive convection in a fluid layer. In Conclusion, we have studied the flow of a compressible (density gradient type) non-linear fluid down an inclined plane, subject to radiation boundary condition. The heat transfer is also considered where a source term, similar to the Arrhenius type reaction, is included. The non-dimensional forms of the equations are solved numerically and the competing effects of conduction, dissipation, heat generation and radiation are discussed. It is observed that the velocity increases rapidly in the region near the inclined surface and is slower in the region near the free surface. Since R{sub 7} is a measure of the heat generation due to chemical reaction, when the reaction is frozen (R{sub 7}=0.0) the temperature distributions would depend only on R{sub 1}, and R{sub 2}, representing the effects of the pressure force developed in the material due to the distribution, R{sub 3} and R{sub 4} viscous dissipation, R{sub 5} the normal stress coefficient, R{sub 6} the measure of the emissivity of the particles to the thermal conductivity, etc. When the flow is not frozen (RP{sub 7} > 0) the temperature inside the flow domain is much higher than those at the inclined and free surfaces. As a result, heat is transferred away from the flow toward both the inclined surface and the free surface with a rate that increases as R{sub 7} increases. For a given temperature, an increase in {zeta} implies that the activation energy is smaller and thus, the reaction ra

  2. Relativistic Random Phase Approximation At Finite Temperature

    SciTech Connect (OSTI)

    Niu, Y. F. [State Key Laboratory for Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China); Physics Department, Faculty of Science, University of Zagreb (Croatia); Paar, N.; Vretenar, D. [Physics Department, Faculty of Science, University of Zagreb (Croatia); Meng, J. [State Key Laboratory for Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China)

    2009-08-26T23:59:59.000Z

    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.

  3. New insights into self-heating in double-gate transistors by solving Boltzmann transport equations

    SciTech Connect (OSTI)

    Thu Trang Nghiêm, T., E-mail: tthutrang.nghiem@gmail.com [Institute of Fundamental Electronics, UMR 8622, CNRS-University of Paris-Sud, Orsay (France); The Center for Thermal Sciences of Lyon, UMR 5008, CNRS–INSA–University of Lyon 1, Villeurbanne (France); Saint-Martin, J.; Dollfus, P. [Institute of Fundamental Electronics, UMR 8622, CNRS-University of Paris-Sud, Orsay (France)

    2014-08-21T23:59:59.000Z

    Electro-thermal effects become one of the most critical issues for continuing the downscaling of electron devices. To study this problem, a new efficient self-consistent electron-phonon transport model has been developed. Our model of phonon Boltzmann transport equation (pBTE) includes the decay of optical phonons into acoustic modes and a generation term given by electron-Monte Carlo simulation. The solution of pBTE uses an analytic phonon dispersion and the relaxation time approximation for acoustic and optical phonons. This coupled simulation is applied to investigate the self-heating effects in a 20?nm-long double gate MOSFET. The temperature profile per mode and the comparison between Fourier temperature and the effective temperature are discussed. Some significant differences occur mainly in the hot spot region. It is shown that under the influence of self-heating effects, the potential profile is modified and both the drain current and the electron ballisticity are reduced because of enhanced electron-phonon scattering rates.

  4. 500°F Absorption Heat Pump Under Development 

    E-Print Network [OSTI]

    Davidson, W. F.; Erickson, D. C.

    1986-01-01T23:59:59.000Z

    stainless steels having corrosion rates of less than 1 mil per year at temperatures up to approximately the chemical stability limit, and mild steel at temperatures about lOOoe lower. Also, the alkali metal nitrates are routinely added to aqueous... vacuums measurements were also taken. Three materials were tested: mild steel (A36), stainless steel (304), and pack aluminized stainless steel. The latter has been found to be effective in resisting anhydrous nitrate corrosion at temperatures above...

  5. Heat distribution ceramic processing method

    DOE Patents [OSTI]

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

    2001-01-01T23:59:59.000Z

    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.

  6. Heat and Power Systems Design

    E-Print Network [OSTI]

    Spriggs, H. D.; Shah, J. V.

    HEAT AND POWER SYSTEMS DESIGN H. D. Spriggs and J. V. Shah, Leesburg. VA ABSTRACT The selection of heat and power systems usually does not include a thorough analysis of the process heating. cooling and power requirements. In most cases..., these process requirements are accepted as specifications before heat and power systems are selected and designed. In t~is article we describe how Process Integration using Pinch Technology can be used to understand and achieve the minimum process heating...

  7. TEMP: A finite line heat transfer code for geologic repositories for nuclear waste

    SciTech Connect (OSTI)

    Wurm, K.J.; Bloom, S.G.; Atterbury, W.G.; Hetteberg, J.R.

    1987-10-01T23:59:59.000Z

    TEMP is a FORTRAN computer code for calculating temperatures in a geologic repository for nuclear waste. It will calculate the incremental temperature contributed by a single heat source, by an infinite array of heat sources, or by heat sources geometrically arranged in a finite array. In the finite array geometry, different types of heat sources can be placed in different regions at different times to more closely approximate the emplacement of waste in a repository. TEMP uses a semi-analytical technique for solving the equation for a heat producing finite length line source in an infinite and isotropic medium. Temperature contributions from individual heat sources are superimposed to determine the temperature at a specific location and time in a repository of multiple heat sources. Thermal conductivity of the geologic medium can be a function of temperature, and, when it is, an approximation is made for the temperature dependence of thermal diffusivity. This report derives the equations solved by TEMP and documents its accuracy by comparing its results to known analytical solutions and to the finite-difference and finite-element heat transfer codes HEATING5, HEATING6, THAC-SIP-3D, SPECTROM-41, and STEALTH-2D. The temperature results from TEMP are shown to be very accurate when compared to the analytical solutions and to the results from the finite-difference and finite-element codes. 8 refs., 97 figs., 39 tabs.

  8. Overshooting by differential heating

    E-Print Network [OSTI]

    Andrássy, R

    2015-01-01T23:59:59.000Z

    On the long nuclear time scale of stellar main-sequence evolution, even weak mixing processes can become relevant for redistributing chemical species in a star. We investigate a process of "differential heating," which occurs when a temperature fluctuation propagates by radiative diffusion from the boundary of a convection zone into the adjacent radiative zone. The resulting perturbation of the hydrostatic equilibrium causes a flow that extends some distance from the convection zone. We study a simplified differential-heating problem with a static temperature fluctuation imposed on a solid boundary. The astrophysically relevant limit of a high Reynolds number and a low P\\'eclet number (high thermal diffusivity) turns out to be interestingly non-intuitive. We derive a set of scaling relations for the stationary differential heating flow. A numerical method adapted to a high dynamic range in flow amplitude needed to detect weak flows is presented. Our two-dimensional simulations show that the flow reaches a sta...

  9. Entangled games are hard to approximate

    E-Print Network [OSTI]

    Julia Kempe; Hirotada Kobayashi; Keiji Matsumoto; Ben Toner; Thomas Vidick

    2007-11-21T23:59:59.000Z

    We establish the first hardness results for the problem of computing the value of one-round games played by a verifier and a team of provers who can share quantum entanglement. In particular, we show that it is NP-hard to approximate within an inverse polynomial the value of a one-round game with (i) quantum verifier and two entangled provers or (ii) classical verifier and three entangled provers. Previously it was not even known if computing the value exactly is NP-hard. We also describe a mathematical conjecture, which, if true, would imply hardness of approximation to within a constant. We start our proof by describing two ways to modify classical multi-prover games to make them resistant to entangled provers. We then show that a strategy for the modified game that uses entanglement can be ``rounded'' to one that does not. The results then follow from classical inapproximability bounds. Our work implies that, unless P=NP, the values of entangled-prover games cannot be computed by semidefinite programs that are polynomial in the size of the verifier's system, a method that has been successful for more restricted quantum games.

  10. Analytic approximate radiation effects due to Bremsstrahlung

    SciTech Connect (OSTI)

    Ben-Zvi I.

    2012-02-01T23:59:59.000Z

    The purpose of this note is to provide analytic approximate expressions that can provide quick estimates of the various effects of the Bremsstrahlung radiation produced relatively low energy electrons, such as the dumping of the beam into the beam stop at the ERL or field emission in superconducting cavities. The purpose of this work is not to replace a dependable calculation or, better yet, a measurement under real conditions, but to provide a quick but approximate estimate for guidance purposes only. These effects include dose to personnel, ozone generation in the air volume exposed to the radiation, hydrogen generation in the beam dump water cooling system and radiation damage to near-by magnets. These expressions can be used for other purposes, but one should note that the electron beam energy range is limited. In these calculations the good range is from about 0.5 MeV to 10 MeV. To help in the application of this note, calculations are presented as a worked out example for the beam dump of the R&D Energy Recovery Linac.

  11. Solar heating and hot water system installed at Shoney's Restaurant, North Little Rock, Arkansas. Final report

    SciTech Connect (OSTI)

    None

    1980-08-01T23:59:59.000Z

    The solar heating system is designed to supply a major portion of the space and water heating requirements for a newly built Shoney's Big Boy Restaurant which was installed with completion occurring in December 1979. The restaurant has a floor space of approximately 4,650 square feet and requires approximately 1500 gallons of hot water daily. The solar energy system consists of 1,428 square feet of Chamberlain flat plate liquid collector subsystem, and a 1500 gallon storage subsystem circulating hot water producing 321 x 10/sup 6/ Btu/yr (specified) building heating and hot water heating. Designer - Energy Solutions, Incorporated. Contractor - Stephens Brothers, Incorporated. This report includes extracts from site files, specification references for solar modifications to existing building heating and hot water systems, drawings installation, operation and maintenance instructions.

  12. Air heating system

    DOE Patents [OSTI]

    Primeau, John J. (19800 Seminole Rd., Euclid, OH 44117)

    1983-03-01T23:59:59.000Z

    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.

  13. Acoustical heat pumping engine

    DOE Patents [OSTI]

    Wheatley, John C. (Los Alamos, NM); Swift, Gregory W. (Los Alamos, NM); Migliori, Albert (Santa Fe, NM)

    1983-08-16T23:59:59.000Z

    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.

  14. Acoustical heat pumping engine

    DOE Patents [OSTI]

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

    1983-08-16T23:59:59.000Z

    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.

  15. Solar industrial process heat

    SciTech Connect (OSTI)

    Lumsdaine, E.

    1981-04-01T23:59:59.000Z

    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)

  16. Geothermal space heating applications for the Fort Peck Indian Reservation in the vicinity of Poplar, Montana. Final report, August 20, 1979-May 31, 1980

    SciTech Connect (OSTI)

    Birman, J.H.; Cohen, J.; Spencer, G.J.

    1980-10-01T23:59:59.000Z

    The results of a first-stage evaluation of the overall feasibility of utilizing geothermal waters from the Madison aquifer in the vicinity of Poplar, Montana for space heating are reported. A preliminary assessment of the resource characteristics, a preliminary design and economic evaluation of a geothermal heating district and an analysis of environmental and institutional issues are included. Preliminary investigations were also made into possible additional uses of the geothermal resource, including ethanol production. The results of the resource analysis showed that the depth to the top of the Madison occurs at approximately 5,500 feet at Poplar, and the Madison Group is characterized by low average porosity (about 5 percent) and permeability (about 0.004 gal/day-ft), and by hot water production rates of a few tens of gallons per minute from intervals a few feet thick. The preliminary heating district system effort for the town of Poplar included design heat load estimates, a field development concept, and preliminary design of heat extraction and hot water distribution systems. The environmental analysis, based on current data, indicated that resource development is not expected to result in undue impacts. The institutional analysis concluded that a Tribal geothermal utility could be established, but no clear-cut procedure can be identified without a more comprehensive evaluation of legal and jurisdistional issues. The economic evaluation found that, if the current trend of rapidly increasing prices for fossil fuels continues, a geothermal heating district within Poplar could be a long-term, economically attractive alternative to current energy sources.

  17. Stochastic Approximation and Its Application in MCMC

    E-Print Network [OSTI]

    Cheng, Yichen

    2013-05-31T23:59:59.000Z

    for optimization problems. However, it can not guarantee the global optima to be located unless a logarithmic cooling schedule is used. However, the logarithm rate is so slow that no one can afford such a long cpu time. We proposed a new stochastic optimization...

  18. On the Computational Power of Molecular Heat Engines

    E-Print Network [OSTI]

    Dominik Janzing

    2005-02-02T23:59:59.000Z

    A heat engine is a machine which uses the temperature difference between a hot and a cold reservoir to extract work. Here both reservoirs are quantum systems and a heat engine is described by a unitary transformation which decreases the average energy of the bipartite system. On the molecular scale, the ability of implementing such a unitary heat engine is closely connected to the ability of performing logical operations and classical computing. This is shown by several examples: (1) The most elementary heat engine is a SWAP-gate acting on 1 hot and 1 cold two-level systems with different energy gaps. (2) An optimal unitary heat engine on a pair of 3-level systems can directly implement OR and NOT gates, as well as copy operations. The ability to implement this heat engine on each pair of 3-level systems taken from the hot and the cold ensemble therefore allows universal classical computation. (3) Optimal heat engines operating on one hot and one cold oscillator mode with different frequencies are able to calculate polynomials and roots approximately. (4) An optimal heat engine acting on 1 hot and n cold 2-level systems with different level spacings can even solve the NP-complete problem KNAPSACK. Whereas it is already known that the determination of ground states of interacting many-particle systems is NP-hard, the optimal heat engine is a thermodynamic problem which is NP-hard even for n non-interacting spin systems. This result suggest that there may be complexity-theoretic limitations on the efficiency of molecular heat engines.

  19. Enhanced Heat Flow in the Hydrodynamic Collisionless Regime

    SciTech Connect (OSTI)

    Meppelink, R.; Rooij, R. van; Vogels, J. M.; Straten, P. van der [Atom Optics and Ultrafast Dynamics, Utrecht University, P.O. Box 80000, 3508 TA Utrecht (Netherlands)

    2009-08-28T23:59:59.000Z

    We study the heat conduction of a cold, thermal cloud in a highly asymmetric trap. The cloud is axially hydrodynamic, but due to the asymmetric trap radially collisionless. By locally heating the cloud we excite a thermal dipole mode and measure its oscillation frequency and damping rate. We find an unexpectedly large heat conduction compared to the homogeneous case. The enhanced heat conduction in this regime is partially caused by atoms with a high angular momentum spiraling in trajectories around the core of the cloud. Since atoms in these trajectories are almost collisionless they strongly contribute to the heat transfer. We observe a second, oscillating hydrodynamic mode, which we identify as a standing wave sound mode.

  20. Hydrogen capacity and absorption rate of the SAES St707 non-evaporable getter at various temperatures.

    SciTech Connect (OSTI)

    Hsu, Irving; Mills, Bernice E.

    2010-08-01T23:59:59.000Z

    A prototype of a tritium thermoelectric generator (TTG) is currently being developed at Sandia. In the TTG, a vacuum jacket reduces the amount of heat lost from the high temperature source via convection. However, outgassing presents challenges to maintaining a vacuum for many years. Getters are chemically active substances that scavenge residual gases in a vacuum system. In order to maintain the vacuum jacket at approximately 1.0 x 10{sup -4} torr for decades, nonevaporable getters that can operate from -55 C to 60 C are going to be used. This paper focuses on the hydrogen capacity and absorption rate of the St707{trademark} non-evaporable getter by SAES. Using a getter testing manifold, we have carried out experiments to test these characteristics of the getter over the temperature range of -77 C to 60 C. The results from this study can be used to size the getter appropriately.