Sample records for radiative heating rates

  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. 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

  4. 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

  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. 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.

  7. 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.

  8. 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.

  9. Cloud Effects on Radiative Heating Rate Profiles over Darwin using ARM and A-train Radar/Lidar Observations

    SciTech Connect (OSTI)

    Thorsen, Tyler J.; Fu, Qiang; Comstock, Jennifer M.

    2013-06-11T23:59:59.000Z

    Observations of clouds from the ground-based U.S. Department of Energy Atmospheric Radiation Measurement program (ARM) and satellite-based A-train are used to compute cloud radiative forcing profiles over the ARM Darwin, Australia site. Cloud properties are obtained from both radar (the ARM Millimeter Cloud Radar (MMCR) and the CloudSat satellite in the A-train) and lidar (the ARM Micropulse lidar (MPL) and the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite in the A-train) observations. Cloud microphysical properties are taken from combined radar and lidar retrievals for ice clouds and radar only or lidar only retrievals for liquid clouds. Large, statistically significant differences of up to 1.43 K/day exist between the mean ARM and A-train net cloud radiative forcing profiles. The majority of the difference in cloud radiative forcing profiles is shown to be due to a large difference in the cloud fraction above 12 km. Above this altitude the A-train cloud fraction is significantly larger because more clouds are detected by CALIPSO than by the ground-based MPL. It is shown that the MPL is unable to observe as many high clouds as CALIPSO due to being more frequently attenuated and a poorer sensitivity even in otherwise clear-sky conditions. After accounting for cloud fraction differences and instrument sampling differences due to viewing platform we determined that differences in cloud radiative forcing due to the retrieved ice cloud properties is relatively small. This study demonstrates that A-train observations are better suited for the calculation cloud radiative forcing profiles. In addition, we find that it is necessary to supplement CloudSat with CALIPSO observations to obtain accurate cloud radiative forcing profiles since a large portion of clouds at Darwin are detected by CALIPSO only.

  10. 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.

  11. 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.

  12. Tropical Cloud Properties and Radiative Heating Profiles

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

    Mather, James

    We have generated a suite of products that includes merged soundings, cloud microphysics, and radiative fluxes and heating profiles. The cloud microphysics is strongly based on the ARM Microbase value added product (Miller et al., 2003). We have made a few changes to the microbase parameterizations to address issues we observed in our initial analysis of the tropical data. The merged sounding product is not directly related to the product developed by ARM but is similar in that it uses the microwave radiometer to scale the radiosonde column water vapor. The radiative fluxes also differ from the ARM BBHRP (Broadband Heating Rate Profile) product in terms of the radiative transfer model and the sampling interval.

  13. 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

  14. Solid state radiative heat pump

    DOE Patents [OSTI]

    Berdahl, P.H.

    1984-09-28T23:59:59.000Z

    A solid state radiative heat pump operable at room temperature (300 K) utilizes a semiconductor having a gap energy in the range of 0.03-0.25 eV and operated reversibly to produce an excess or deficit of change carriers as compared equilibrium. In one form of the invention an infrared semiconductor photodiode is used, with forward or reverse bias, to emit an excess or deficit of infrared radiation. In another form of the invention, a homogenous semiconductor is subjected to orthogonal magnetic and electric fields to emit an excess or deficit of infrared radiation. Three methods of enhancing transmission of radiation the active surface of the semiconductor are disclosed. In one method, an anti-refection layer is coated into the active surface of the semiconductor, the anti-reflection layer having an index of refraction equal to the square root of that of the semiconductor. In the second method, a passive layer is speaced trom the active surface of the semiconductor by a submicron vacuum gap, the passive layer having an index of refractive equal to that of the semiconductor. In the third method, a coupler with a paraboloid reflecting surface surface is in contact with the active surface of the semiconductor, the coupler having an index of refraction about the same as that of the semiconductor.

  15. Solid state radiative heat pump

    DOE Patents [OSTI]

    Berdahl, Paul H. (Oakland, CA)

    1986-01-01T23:59:59.000Z

    A solid state radiative heat pump (10, 50, 70) operable at room temperature (300.degree. K.) utilizes a semiconductor having a gap energy in the range of 0.03-0.25 eV and operated reversibly to produce an excess or deficit of charge carriers as compared to thermal equilibrium. In one form of the invention (10, 70) an infrared semiconductor photodiode (21, 71) is used, with forward or reverse bias, to emit an excess or deficit of infrared radiation. In another form of the invention (50), a homogeneous semiconductor (51) is subjected to orthogonal magnetic and electric fields to emit an excess or deficit of infrared radiation. Three methods of enhancing transmission of radiation through the active surface of the semiconductor are disclosed. In one method, an anti-reflection layer (19) is coated into the active surface (13) of the semiconductor (11), the anti-reflection layer (19) having an index of refraction equal to the square root of that of the semiconductor (11). In the second method, a passive layer (75) is spaced from the active surface (73) of the semiconductor (71) by a submicron vacuum gap, the passive layer having an index of refractive equal to that of the semiconductor. In the third method, a coupler (91) with a paraboloid reflecting surface (92) is in contact with the active surface (13, 53) of the semiconductor (11, 51), the coupler having an index of refraction about the same as that of the semiconductor.

  16. Radiative Heat Transfer in Enhanced Hydrogen Outgassing of Glass

    E-Print Network [OSTI]

    Kitamura, Rei; Pilon, Laurent

    2009-01-01T23:59:59.000Z

    Kaviany and B.P. Singh, “Radiative heat transfer in porousmedia”, Advances in Heat Transfer, vol. 23, no. 23, pp. 133–Thermal radiation heat transfer, Hemisphere Publishing Co. ,

  17. 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.

  18. Radiative heat transfer between dielectric bodies

    E-Print Network [OSTI]

    Svend-Age Biehs

    2011-03-16T23:59:59.000Z

    The recent development of a scanning thermal microscope (SThM) has led to measurements of radiative heat transfer between a heated sensor and a cooled sample down to the nanometer range. This allows for comparision of the known theoretical description of radiative heat transfer, which is based on fluctuating electrodynamics, with experiment. The theory itself is a macroscopic theory, which can be expected to break down at distances much smaller than 10-8m. Against this background it seems to be reasonable to revisit the known macroscopic theory of fluctuating electrodynamics and of radiative heat transfer.

  19. Impact of subgrid-scale radiative heating variability on the...

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

    subgrid-scale radiative heating variability on the stratocumulus-to-trade cumulus transition in climate models. Impact of subgrid-scale radiative heating variability on the...

  20. Analysis of tropical radiative heating profiles: A comparison...

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

    diurnal variability in the radiative heating profiles; and a significantly lower level of zero net radiative heating. Citation: McFarlane SA, JH Mather, and TP...

  1. Photon Radiation in a Heat Bath

    E-Print Network [OSTI]

    P V Landshoff; J C Taylor

    1994-04-26T23:59:59.000Z

    We discuss the bremsstrahlung of photons into a heat bath, and calculate from first principles the energy radiated. Even to lowest order the spectrum of the radiation at low frequency is no more singular than at zero temperature. In addition to the obvious contributions, this spectrum includes terms associated with fluctuations. [Revised version has additional explanations

  2. 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.

  3. Radiation detector system having heat pipe based cooling

    DOE Patents [OSTI]

    Iwanczyk, Jan S.; Saveliev, Valeri D.; Barkan, Shaul

    2006-10-31T23:59:59.000Z

    A radiation detector system having a heat pipe based cooling. The radiation detector system includes a radiation detector thermally coupled to a thermo electric cooler (TEC). The TEC cools down the radiation detector, whereby heat is generated by the TEC. A heat removal device dissipates the heat generated by the TEC to surrounding environment. A heat pipe has a first end thermally coupled to the TEC to receive the heat generated by the TEC, and a second end thermally coupled to the heat removal device. The heat pipe transfers the heat generated by the TEC from the first end to the second end to be removed by the heat removal device.

  4. 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

  5. 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

  6. RADIATIVE HEAT TRANSFER WITH QUASI-MONTE CARLO METHODS

    E-Print Network [OSTI]

    RADIATIVE HEAT TRANSFER WITH QUASI-MONTE CARLO METHODS A. Kersch1 W. Moroko2 A. Schuster1 1Siemens of Quasi-Monte Carlo to this problem. 1.1 Radiative Heat Transfer Reactors In the manufacturing of the problems which can be solved by such a simulation is high accuracy modeling of the radiative heat transfer

  7. Radiation Leukemogenesis at Low Dose Rates

    SciTech Connect (OSTI)

    Weil, Michael; Ullrich, Robert

    2013-09-25T23:59:59.000Z

    The major goals of this program were to study the efficacy of low dose rate radiation exposures for the induction of acute myeloid leukemia (AML) and to characterize the leukemias that are caused by radiation exposures at low dose rate. An irradiator facility was designed and constructed that allows large numbers of mice to be irradiated at low dose rates for protracted periods (up to their life span). To the best of our knowledge this facility is unique in the US and it was subsequently used to study radioprotectors being developed for radiological defense (PLoS One. 7(3), e33044, 2012) and is currently being used to study the role of genetic background in susceptibility to radiation-induced lung cancer. One result of the irradiation was expected; low dose rate exposures are ineffective in inducing AML. However, another result was completely unexpected; the irradiated mice had a very high incidence of hepatocellular carcinoma (HCC), approximately 50%. It was unexpected because acute exposures are ineffective in increasing HCC incidence above background. This is a potential important finding for setting exposure limits because it supports the concept of an 'inverse dose rate effect' for some tumor types. That is, for the development of some tumor types low dose rate exposures carry greater risks than acute exposures.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. RADIATIVE HEAT TRANSFER WITH QUASIMONTE CARLO METHODS \\Lambda

    E-Print Network [OSTI]

    RADIATIVE HEAT TRANSFER WITH QUASI­MONTE CARLO METHODS \\Lambda A. Kersch 1 W. Morokoff 2 A accuracy modeling of the radiative heat transfer from the heater to the wafer. Figure 1 shows the draft Carlo simulation is often used to solve radiative transfer problems where complex physical phenomena

  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. Reduce Radiation Losses from Heating Equipment

    SciTech Connect (OSTI)

    Not Available

    2006-01-01T23:59:59.000Z

    This DOE Industrial Technologies Program tip sheet describes how to save energy and costs by reducing expensive heat losses from industrial heating equipment, such as furnaces.

  15. 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...

  16. 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.

  17. AOSC 621AOSC 621 Radiative Heating/CoolingRadiative Heating/Cooling

    E-Print Network [OSTI]

    Li, Zhanqing

    ? Why drop off near sfc? 4 #12;Net flux Net flux: F = F+ - F- 1 2 F-(1) F+(1) F-(2) F+(2) Net energy at the top of the atmosphere is zero. Then we can write 1' ' )',( )'()0,()( 0 * dz dz zzdT zBzTBzF z z F F · The heating rate at z is defined as follows: )( )( d zdF zH net four termsofconsistwilland dz A

  18. 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.

  19. Small distance expansion for radiative heat transfer between curved objects

    E-Print Network [OSTI]

    Golyk, Vladyslav A.

    We develop a small distance expansion for the radiative heat transfer between gently curved objects, in terms of the ratio of distance to radius of curvature. A gradient expansion allows us to go beyond the lowest-order ...

  20. Effect of radiative heat transfer on the coagulation dynamics of combustion-generated particles

    SciTech Connect (OSTI)

    Mackowski, D.W. (Auburn Univ., AL (United States)); Tassopoulos, M.; Rosner, D.E. (Yale Univ., New Haven, CT (United States))

    1994-01-01T23:59:59.000Z

    We examine the influences of radiation heat transfer on the size and number density evolution of small coagulating particles. On a microscopic level, radiative emission and/or absorption by the particle will perturb the gas temperature field adjacent to each particle. As a result of thermophoretic particle transport, the nonequilibrium condition can alter the collision rates with neighboring particles. A simplified analysis of the thermophoretic coagulation mechanism suggests that net radiative cooling of the particles can lead to an accelerated growth of [mu]m-sized particles, whereas net radiative heating can act to essentially freeze coagulation rates. On the macroscopic level, the addition or removal of heat in the gas through radiative absorption emission by the particle cloud can also significantly alter, through thermophoretic transport, the local particle number density. Under certain cases these effects can augment the accelerated coagulation rates that occur under radiative cooling conditions. We also examine the particular situation of equilibrium between particle cloud radiative absorption and emission - which results in no net macroscopic effect on the gas. 30 refs., 9 figs.

  1. Enhanced radiative heat transfer between nanostructured gold plates

    E-Print Network [OSTI]

    R. Guérout; J. Lussange; F. S. S. Rosa; J. -P. Hugonin; D. A. R. Dalvit; J. -J. Greffet; A. Lambrecht; S. Reynaud

    2012-03-07T23:59:59.000Z

    We compute the radiative heat transfer between nanostructured gold plates in the framework of the scattering theory. We predict an enhancement of the heat transfer as we increase the depth of the corrugations while keeping the distance of closest approach fixed. We interpret this effect in terms of the evolution of plasmonic and guided modes as a function of the grating's geometry.

  2. 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

  3. Computation of radiative heat transport across a nanoscale vacuum gap

    SciTech Connect (OSTI)

    Budaev, Bair V., E-mail: bair@berkeley.edu; Bogy, David B., E-mail: dbogy@berkeley.edu [University of California, Etcheverry Hall, MC 1740, Berkeley, California 94720-1740 (United States)

    2014-02-10T23:59:59.000Z

    Radiation heat transport across a vacuum gap between two half-spaces is studied. By consistently applying only the fundamental laws of physics, we obtain an algebraic equation that connects the temperatures of the half-spaces and the heat flux between them. The heat transport coefficient generated by this equation for such structures matches available experimental data for nanoscale and larger gaps without appealing to any additional specific mechanisms of energy transfer.

  4. Radiative Heating in Underexplored Bands Campaign (RHUBC)

    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's PossibleRadiation Protection Radiation Protection Regulations: The FederalRadiative Effects of

  5. Radiative Heating in Underexplored Bands Campaign (RHUBC)

    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's PossibleRadiation Protection Radiation Protection Regulations: The FederalRadiative Effects of

  6. Selective radiative heating of nanostructures using hyperbolic metamaterials

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

    Ding, Ding; Minnich, Austin J

    2015-01-01T23:59:59.000Z

    Hyperbolic metamaterials (HMM) are of great interest due to their ability to break the diffraction limit for imaging and enhance near-field radiative heat transfer. Here we demonstrate that an annular, transparent HMM enables selective heating of a sub-wavelength plasmonic nanowire by controlling the angular mode number of a plasmonic resonance. A nanowire emitter, surrounded by an HMM, appears dark to incoming radiation from an adjacent nanowire emitter unless the second emitter is surrounded by an identical lens such that the wavelength and angular mode of the plasmonic resonance match. Our result can find applications in radiative thermal management.

  7. High-power ELF radiation generated by modulated HF heating of the ionosphere can cause Earthquakes, Cyclones and localized heating

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    transmitter radiates a strong beam of high- frequency (HF) waves modulated at ELF. This HF heating modulates-frequency (HF) radiation in the megahertz range [7]. This heating modulates the electron's temperature in the D

  8. 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

  9. Radiation dose rates from UF{sub 6} cylinders

    SciTech Connect (OSTI)

    Friend, P.J. [Urenco, Capenhurst (United Kingdom)

    1991-12-31T23:59:59.000Z

    This paper describes the results of many studies, both theoretical and experimental, which have been carried out by Urenco over the last 15 years into radiation dose rates from uranium hexafluoride (UF{sub 6}) cylinders. The contents of the cylinder, its history, and the geometry all affect the radiation dose rate. These factors are all examined in detail. Actual and predicted dose rates are compared with levels permitted by IAEA transport regulations.

  10. Giant radiation heat transfer through the micron gaps

    E-Print Network [OSTI]

    Nefedov, Igor

    2011-01-01T23:59:59.000Z

    Near-field heat transfer between two closely spaced radiating media can exceed in orders radiation through the interface of a single black body. This effect is caused by exponentially decaying (evanescent) waves which form the photon tunnel between two transparent boundaries. However, in the mid-infrared range it holds when the gap between two media is as small as few tens of nanometers. We propose a new paradigm of the radiation heat transfer which makes possible the strong photon tunneling for micron thick gaps. For it the air gap between two media should be modified, so that evanescent waves are transformed inside it into propagating ones. This modification is achievable using a metamaterial so that the direct thermal conductance through the metamaterial is practically absent and the photovoltaic conversion of the transferred heat is not altered by the metamaterial.

  11. 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 ...

  12. Radiative heat transfer in a hydrous mantle transition zone Sylvia-Monique Thomas a,n

    E-Print Network [OSTI]

    Jacobsen, Steven D.

    Radiative heat transfer in a hydrous mantle transition zone Sylvia-Monique Thomas a,n , Craig R contribute significantly to heat transfer in the mantle and demonstrate the importance of radiative heat, radiative heat transfer was considered relatively unimportant in the mantle. Earlier experimental work

  13. 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.

  14. Historical mutation rates predict susceptibility to radiation in Chernobyl birds

    E-Print Network [OSTI]

    Mousseau, Timothy A.

    Historical mutation rates predict susceptibility to radiation in Chernobyl birds A. P. MÃ?LLER* , J in the evolutionary past. Radioactive contamination from Chernobyl constitutes one such extreme perturbation of radiation from Chernobyl are also the species that in the past have been most susceptible to factors

  15. A new method for solving radiative heat problems in glass

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    RANA 99­06 A new method for solving radiative heat problems in glass B.J. van der Linden --- R, The Netherlands e­mail: linden@win.tue.nl 15th May 2000 #12; Abstract In the production of glass, temperature Conclusion 25 2 #12; Chapter 1 Introduction The production of glass belongs to the oldest forms of human

  16. A new method for solving radiative heat problems in glass

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    RANA 99-06 A new method for solving radiative heat problems in glass B.J. van der Linden -- R, The Netherlands e-mail: linden@win.tue.nl 15th May 2000 #12;Abstract In the production of glass, temperature plays Conclusion 25 2 #12;Chapter 1 Introduction The production of glass belongs to the oldest forms of human

  17. Temperature measurements using multicolor pyrometry in thermal radiation heating environments

    SciTech Connect (OSTI)

    Fu, Tairan, E-mail: trfu@mail.tsinghua.edu.cn [Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China) [Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China); Beijing Key Laboratory of CO2 Utilization and Reduction Technology, Beijing 100084 (China); Liu, Jiangfan; Duan, Minghao; Zong, Anzhou [Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China)] [Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China)

    2014-04-15T23:59:59.000Z

    Temperature measurements are important for thermal-structural experiments in the thermal radiation heating environments such as used for thermal-structural stress analyses. This paper describes the use of multicolor pyrometry for the measurements of diffuse surfaces in thermal radiation environments that eliminates the effects of background radiation reflections and unknown emissivities based on a least-squares algorithm. The near-infrared multicolor pyrometer had a spectral range of 1100–2400 nm, spectrum resolution of 6 nm, maximum sampling frequency of 2 kHz, working distance of 0.6 m to infinity, temperature range of 700–1700 K. The pyrometer wavelength response, nonlinear intensity response, and spectral response were all calibrated. The temperature of a graphite sample irradiated by quartz lamps was then measured during heating and cooling using the least-squares algorithm based on the calibrated irradiation data. The experiments show that higher temperatures and longer wavelengths are more suitable for the thermal measurements in the quartz lamp radiation heating system. This analysis provides a valuable method for temperature measurements of diffuse surfaces in thermal radiation environments.

  18. 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.

  19. Calculating Radiative Heat Transfer in an Axisymmetric Closed Chamber: An Application

    E-Print Network [OSTI]

    New York at Stoney Brook, State University of

    the parallelization of the radiative heat transfer model introduced by Naraghi and Nunes of Manhattan College [8

  20. 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.

  1. Radiative heat transfer at nanoscale mediated by surface plasmons for highly doped Emmanuel Rousseau

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Radiative heat transfer at nanoscale mediated by surface plasmons for highly doped silicon the role of surface plasmons for nanoscale radiative heat transfer between doped silicon surfaces. We derive a new accurate and closed-form expression of the radiative near- field heat transfer. We also

  2. Radiative heat transfer in anisotropic many-body systems: Tuning and enhancement

    SciTech Connect (OSTI)

    Nikbakht, Moladad, E-mail: mnik@znu.ac.ir [Department of Physics, Faculty of Sciences, University of Zanjan, Zanjan 45371-38791 (Iran, Islamic Republic of)

    2014-09-07T23:59:59.000Z

    A general formalism for calculating the radiative heat transfer in many body systems with anisotropic component is presented. Our scheme extends the theory of radiative heat transfer in isotropic many body systems to anisotropic cases. In addition, the radiative heating of the particles by the thermal bath is taken into account in our formula. It is shown that the radiative heat exchange (HE) between anisotropic particles and their radiative cooling/heating (RCH) could be enhanced several order of magnitude than that of isotropic particles. Furthermore, we demonstrate that both the HE and RCH can be tuned dramatically by particles relative orientation in many body systems.

  3. 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 ...

  4. 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...

  5. High pressure argon ionization chamber systems for the measurement of environmental radiation exposure rates

    E-Print Network [OSTI]

    DeCampo, J A; Raft, P D

    1972-01-01T23:59:59.000Z

    High pressure argon ionization chamber systems for the measurement of environmental radiation exposure rates

  6. 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

  7. 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

  8. Reduce Radiation Losses from Heating Equipment | Department of Energy

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

    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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreakingMay 2015 < prevQuick Guide:U.N.June 8,PastRadiation Losses from Heating

  9. 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.

  10. 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.

  11. Modeling ofHybrid (Heat Radiation and Microwave) High Temperature Processing ofLimestone

    E-Print Network [OSTI]

    Yakovlev, Vadim

    Modeling ofHybrid (Heat Radiation and Microwave) High Temperature Processing ofLimestone Shawn M (electromagnetic and thermal) modeling to cover practically valuable scenarios of hybrid (heat radiation is applied to the process of hybrid heating of cylindrical samples of limestone in Ceralink's MAT TM kiln

  12. Heat transfer through a water spray curtain under the effect of a strong radiative source

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Heat transfer through a water spray curtain under the effect of a strong radiative source P. Boulet - mail Pascal.Boulet@lemta.uhp-nancy.fr Keywords : heat transfer, radiative transfer, vaporization, convection, water spray Abstract Heat transfer inside a participating medium, made of droplets flowing in gas

  13. 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.

  14. Thermal heat radiation, near-field energy density and near-field radiative heat transfer of coated materials

    E-Print Network [OSTI]

    Svend-Age Biehs

    2011-03-15T23:59:59.000Z

    We investigate the thermal radiation and thermal near-field energy density of a metal-coated semi-infinite body for different substrates. We show that the surface polariton coupling within the metal coating leads to an enhancement of the TM-mode part of the thermal near-field energy density when a polar substrate is used. In this case the result obtained for a free standing metal film is retrieved. In contrast, in the case of a metal substrate there is no enhancement in the TM-mode part, as can also be explained within the framework of surface plasmon coupling within the coating. Finally, we discuss the influence of the enhanced thermal energy density on the near-field radiative heat transfer between a simple semi-infinite and a coated semi-infinite body for different material combinations.

  15. Field dependent emission rates in radiation damaged GaAs

    SciTech Connect (OSTI)

    Fleming, R. M.; Myers, S. M.; Wampler, W. R.; Lang, D. V.; Seager, C. H.; Campbell, J. M. [Sandia National Laboratories, Albuquerque, New Mexico 87185-1415 (United States)

    2014-07-07T23:59:59.000Z

    We have measured the temperature and field dependence of emission rates from five traps in electron damaged GaAs. Four of the traps have previously been identified as radiation defects. One of the traps, seen in higher doped diodes, has not been previously identified. We have fit the data to a multiphonon emission theory that allows recombination in GaAs to be characterized over a broad range of temperature and electric field. These results demonstrate an efficient method to calculate field-dependent emission rates in GaAs.

  16. Analysis of a flexible polymeric film with imbedded micro heat pipes for spacecraft radiators

    E-Print Network [OSTI]

    McDaniels, Deborah Marie

    2001-01-01T23:59:59.000Z

    radiators are being developed to accommodate deployment mechanisms. An analytical model suggests that a lightweight polymeric material with imbedded micro heat pipe arrays can meet heat dissipation requirements while contributing less mass than competing...

  17. On the Tropospheric Response to Anomalous Stratospheric Wave Drag and Radiative Heating

    E-Print Network [OSTI]

    On the Tropospheric Response to Anomalous Stratospheric Wave Drag and Radiative Heating DAVID W. J of anomalous diabatic heating in the polar stratosphere as stratospheric temperatures relax to climatology

  18. Radiative Heat Transfer in Enhanced Hydrogen Outgassing of Glass

    E-Print Network [OSTI]

    Kitamura, Rei; Pilon, Laurent

    2009-01-01T23:59:59.000Z

    slabs. Moreover, the total heat input during furnace heatingperformed for the same heat input. The optical propertiesheating for the same total heat input. Similarly, Figure 7

  19. 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.

  20. 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 ...

  1. Radiative component and combined heat transfer in the thermal calculation of finned tube banks

    SciTech Connect (OSTI)

    Stehlik, P. [Technical Univ. of Brno (Czech Republic). Dept. of Process Engineering] [Technical Univ. of Brno (Czech Republic). Dept. of Process Engineering

    1999-01-01T23:59:59.000Z

    For more exact calculation of combined heat transfer in the case of finned tube banks (e.g., in the convective section of a furnace), the radiative heat transfer cannot be neglected. A new method for relatively simple calculation of total heat flux (convection + radiation + conduction in fins) is fully compatible with that for bare tube banks/bundles developed earlier. It is based on the method of radiative coefficients. However, the resulting value of heat flux must be corrected due to fin thickness and especially due to the fin radiative influence. For this purpose the so-called multiplicator of heat flux was introduced. The applicability of this methods has been demonstrated on a tubular fired heater convective section. A developed computer program based on the method has also been used for an analysis of the influence of selected parameters to show the share of radiation on the total heat flux.

  2. 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.

  3. Near field radiative heat transfer between two nonlocal dielectrics

    E-Print Network [OSTI]

    Singer, F; Joulain, Karl

    2015-01-01T23:59:59.000Z

    We explore in the present work the near-field radiative heat transfer between two semi-infinite parallel nonlocal dielectric planes by means of fluctuational electrodynamics. We use atheory for the nonlocal dielectric permittivityfunction proposed byHalevi and Fuchs. This theory has the advantage to includedifferent models performed in the literature. According to this theory, the nonlocal dielectric function is described by a Lorenz-Drude like single oscillator model, in which the spatial dispersion effects are represented by an additional term depending on the square of the total wavevector k. The theory takes into account the scattering of the electromagneticexcitation at the surface of the dielectric material, which leads to the need of additional boundary conditions in order to solve Maxwell's equations and treat the electromagnetic transmission problem. The additional boundary conditions appear as additional surface scattering parameters in the expressions of the surface impedances. It is shown that the...

  4. 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

  5. Radiation protection instrumentation - ambient and/or directional dose equivalent (rate) meters and/or monitors for beta, X and gamma radiation part 2: high range beta and photon dose and dose rate portable instruments for emergency radiation protection purposes

    E-Print Network [OSTI]

    International Electrotechnical Commission. Geneva

    2007-01-01T23:59:59.000Z

    Radiation protection instrumentation - ambient and/or directional dose equivalent (rate) meters and/or monitors for beta, X and gamma radiation

  6. 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

  7. 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.

  8. Radiative Heat Transfer Analysis of Fibrous Insulation Materials Using the ZonalGEF Method

    E-Print Network [OSTI]

    Yuen, Walter W.

    Radiative Heat Transfer Analysis of Fibrous Insulation Materials Using the Zonal­GEF Method Walter to analyze radiative heat transfer in high porosity insulation materials which have a large scattering for LI900, a material used in the insulation tile for the space shuttle. Comparisons are presented

  9. Radiative Heating and the Buoyant Rise of Magnetic Flux Tubes in the Solar Interior

    E-Print Network [OSTI]

    California at Berkeley, University of

    Radiative Heating and the Buoyant Rise of Magnetic Flux Tubes in the Solar Interior Y. Fan National the e ect of radiative heating on the evolution of thin magnetic ux tubes in the solar interior Solar Observatoryy, 950 N. Cherry Ave., Tucson, AZ 85719. G. H. Fisher Space Sciences Laboratory, Univ

  10. RADIATION HEAT TRANSFER IN TISSUE WELDING AND SOLDERING WITH ULTRAFAST LASERS

    E-Print Network [OSTI]

    Guo, Zhixiong "James"

    RADIATION HEAT TRANSFER IN TISSUE WELDING AND SOLDERING WITH ULTRAFAST LASERS Kyunghan Kim to incorporate transient radiation heat transfer in tissue welding and soldering with use of ultrafast lasers are performed between laser welding and laser soldering. The use of solder is found to substantially enhance

  11. Improved method for calculating the radiation heat generation in the BOR-60 reactor

    SciTech Connect (OSTI)

    Varivtsev, A. V., E-mail: vav3@niiar.ru; Zhemkov, I. Yu. [JSC “SSC RIAR,” Dimitrovgrad-10 (Russian Federation)

    2014-12-15T23:59:59.000Z

    The results of theoretical and experimental studies aimed at determining the radiation heat generation in the BOR-60 reactor reveal the drawbacks of the computational methods used at present. An algorithm that is free from these drawbacks and allows one to determine the radiation heat generation computationally is proposed.

  12. Glass foams: formation, transport properties, and heat, mass, and radiation transfer

    E-Print Network [OSTI]

    Pilon, Laurent

    Glass foams: formation, transport properties, and heat, mass, and radiation transfer Andrei G depend, to a large extent, on foams formed on the surface of the molten glass and of the batch due models for thermophysical and transport properties and heat, mass, and radiation transfer in glass foams

  13. Radiative Heat Transfer in Enhanced Hydrogen Outgassing of Glass

    E-Print Network [OSTI]

    Kitamura, Rei; Pilon, Laurent

    2009-01-01T23:59:59.000Z

    by a heating lamp emitting in the visible and near infraredwith heating in a furnace at 400 o C. The infrared lamp was

  14. 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

  15. 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.

  16. 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 ...

  17. Modulation and amplification of radiative far field heat transfer : towards a simple radiative thermal transistor

    E-Print Network [OSTI]

    Joulain, Karl; Drevillon, Jeremie; Ben-Abdallah, Philippe

    2015-01-01T23:59:59.000Z

    We show in this article that phase change materials (PCM) exhibiting a phase transition between a dielectric state and a metallic state are good candidates to perform modulation as well as amplification of radiative thermal flux. We propose a simple situation in plane parallel geometry where a so-called radiative thermal transistor could be achieved. In this configuration, we put a PCM between two blackbodies at different temperatures. We show that the transistor effect can be achieved easily when this material has its critical temperature between the two blackbody temperatures. We also see, that the more the material is reflective in the metallic state, the more switching effect is realized whereas the more PCM transition is stiff in temperature, the more thermal amplification is high. We finally take the example of VO2 that exhibits an insulator-metallic transition at 68{\\textdegree}C. We show that a demonstrator of a radiative transistor could easily be achieved in view of the heat flux levels predicted. F...

  18. Investigation of spectral radiation heat transfer and NO{sub x} emission in a glass furnace

    SciTech Connect (OSTI)

    Golchert, B.; Zhou, C. Q.; Chang, S. L.; Petrick, M.

    2000-08-02T23:59:59.000Z

    A comprehensive radiation heat transfer model and a reduced NOx kinetics model were coupled with a computational fluid dynamics (CFD) code and then used to investigate the radiation heat transfer, pollutant formation and flow characteristics in a glass furnace. The radiation model solves the spectral radiative transport equation in the combustion space of emitting and absorbing media, i.e., CO{sub 2}, H{sub 2}O, and soot and emission/reflection from the furnace crown. The advanced numerical scheme for calculating the radiation heat transfer is extremely effective in conserving energy between radiation emission and absorption. A parametric study was conducted to investigate the impact of operating conditions on the furnace performance with emphasis on the investigation into the formation of NOx.

  19. 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

  20. 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.

  1. 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.

  2. Graphene-assisted near-field radiative heat transfer between corrugated polar materials

    SciTech Connect (OSTI)

    Liu, X. L.; Zhang, Z. M., E-mail: zhuomin.zhang@me.gatech.edu [G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

    2014-06-23T23:59:59.000Z

    Graphene has attracted great attention in nanoelectronics, optics, and energy harvesting. Here, the near-field radiative heat transfer between graphene-covered corrugated silica is investigated based on the exact scattering theory. It is found that graphene can improve the radiative heat flux between silica gratings by more than one order of magnitude and alleviate the performance sensitivity to lateral shift. The underlying mechanism is mainly attributed to the improved photon tunneling of modes away from phonon resonances. Besides, coating with graphene leads to nonlocal radiative transfer that breaks Derjaguin's proximity approximation and enables corrugated silica to outperform bulk silica in near-field radiation.

  3. Irradiators for measuring the biological effects of low dose-rate ionizing radiation fields

    E-Print Network [OSTI]

    Davidson, Matthew Allen

    2011-01-01T23:59:59.000Z

    Biological response to ionizing radiation differs with radiation field. Particle type, energy spectrum, and dose-rate all affect biological response per unit dose. This thesis describes methods of spectral analysis, ...

  4. Technological Advancements and Error Rates in Radiation Therapy Delivery

    SciTech Connect (OSTI)

    Margalit, Danielle N., E-mail: dmargalit@partners.org [Harvard Radiation Oncology Program, Boston, MA (United States); Harvard Cancer Consortium and Brigham and Women's Hospital/Dana Farber Cancer Institute, Boston, MA (United States); Chen, Yu-Hui; Catalano, Paul J.; Heckman, Kenneth; Vivenzio, Todd; Nissen, Kristopher; Wolfsberger, Luciant D.; Cormack, Robert A.; Mauch, Peter; Ng, Andrea K. [Harvard Cancer Consortium and Brigham and Women's Hospital/Dana Farber Cancer Institute, Boston, MA (United States)

    2011-11-15T23:59:59.000Z

    Purpose: Technological advances in radiation therapy (RT) delivery have the potential to reduce errors via increased automation and built-in quality assurance (QA) safeguards, yet may also introduce new types of errors. Intensity-modulated RT (IMRT) is an increasingly used technology that is more technically complex than three-dimensional (3D)-conformal RT and conventional RT. We determined the rate of reported errors in RT delivery among IMRT and 3D/conventional RT treatments and characterized the errors associated with the respective techniques to improve existing QA processes. Methods and Materials: All errors in external beam RT delivery were prospectively recorded via a nonpunitive error-reporting system at Brigham and Women's Hospital/Dana Farber Cancer Institute. Errors are defined as any unplanned deviation from the intended RT treatment and are reviewed during monthly departmental quality improvement meetings. We analyzed all reported errors since the routine use of IMRT in our department, from January 2004 to July 2009. Fisher's exact test was used to determine the association between treatment technique (IMRT vs. 3D/conventional) and specific error types. Effect estimates were computed using logistic regression. Results: There were 155 errors in RT delivery among 241,546 fractions (0.06%), and none were clinically significant. IMRT was commonly associated with errors in machine parameters (nine of 19 errors) and data entry and interpretation (six of 19 errors). IMRT was associated with a lower rate of reported errors compared with 3D/conventional RT (0.03% vs. 0.07%, p = 0.001) and specifically fewer accessory errors (odds ratio, 0.11; 95% confidence interval, 0.01-0.78) and setup errors (odds ratio, 0.24; 95% confidence interval, 0.08-0.79). Conclusions: The rate of errors in RT delivery is low. The types of errors differ significantly between IMRT and 3D/conventional RT, suggesting that QA processes must be uniquely adapted for each technique. There was a lower error rate with IMRT compared with 3D/conventional RT, highlighting the need for sustained vigilance against errors common to more traditional treatment techniques.

  5. Effective-medium model of wire metamaterials in the problems of radiative heat transfer

    SciTech Connect (OSTI)

    Mirmoosa, M. S., E-mail: mohammad.mirmoosa@aalto.fi; Nefedov, I. S., E-mail: igor.nefedov@aalto.fi; Simovski, C. R., E-mail: konstantin.simovski@aalto.fi [Department of Radio Science and Engineering, School of Electrical Engineering, Aalto University, P. O. Box 13000, 00076 Aalto (Finland); Rüting, F., E-mail: felix.ruting@uam.es [Departamento de Física Teorica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autonoma de Madrid, E-28049 (Spain)

    2014-06-21T23:59:59.000Z

    In the present work, we check the applicability of the effective medium model (EMM) to the problems of radiative heat transfer (RHT) through so-called wire metamaterials (WMMs)—composites comprising parallel arrays of metal nanowires. It is explained why this problem is so important for the development of prospective thermophotovoltaic (TPV) systems. Previous studies of the applicability of EMM for WMMs were targeted by the imaging applications of WMMs. The analogous study referring to the transfer of radiative heat is a separate problem that deserves extended investigations. We show that WMMs with practically realizable design parameters transmit the radiative heat as effectively homogeneous media. Existing EMM is an adequate tool for qualitative prediction of the magnitude of transferred radiative heat and of its effective frequency band.

  6. Radiative Impacts on the Growth of Drops within Simulated Marine Stratocumulus. Part I: Maximum Solar Heating

    E-Print Network [OSTI]

    Harrington, Jerry Y.

    Radiative Impacts on the Growth of Drops within Simulated Marine Stratocumulus. Part I: Maximum Solar Heating CHRISTOPHER M. HARTMAN AND JERRY Y. HARRINGTON Department of Meteorology, The Pennsylvania November 2004) ABSTRACT The effects of solar heating and infrared cooling on the vapor depositional growth

  7. 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

  8. 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...

  9. AEROSOL-CLOUD INTERACTIONS CONTROL OF EARTH RADIATION AND LATENT HEAT RELEASE BUDGETS

    E-Print Network [OSTI]

    Daniel, Rosenfeld

    role in energizing the climate system: they reflect much of the solar radiation back to space and so and aerosols reflect back to space 22.5% of the solar radiation (Figure 1). An additional 8.8% is reflected.1% are absorbed by the surface. Surface evaporation consumes 22.8% of the solar energy that subsequently heats

  10. Radiative Heating in Underexplored Bands Campaign, Phase II

    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's PossibleRadiation Protection Radiation Protection Regulations: The FederalRadiative Effects

  11. Radiative heat transfer in a parallelogram shaped cavity

    E-Print Network [OSTI]

    Dez, V Le

    2015-01-01T23:59:59.000Z

    An exact analytical description of the internal radiative field inside an emitting-absorbing gray semi-transparent medium enclosed in a two-dimensional parallelogram cavity is proposed. The expressions of the incident radiation and the radiative flux field are angularly and spatially discretized with a double Gauss quadrature, and the temperature field is obtained by using an iterative process. Some numerical solutions are tabulated and graphically presented as the benchmark solutions. Temperature and two components of the radiative flux are finally sketched on the whole domain. It is shown that the proposed method gives perfectly smooth results.

  12. Author's personal copy Radiative heat transfer in enhanced hydrogen

    E-Print Network [OSTI]

    Pilon, Laurent

    the physical mechanisms responsible for experimental observations that led to the definition of ``photo tube and heated in a furnace or by an incandescent lamp. It was observed that hydrogen release from the glass sample was faster and stronger when heated by an incandescent lamp than within a furnace. Here

  13. 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

  14. Thermal radiation of laser heated niobium clusters Nb{sub N}{sup +}, 8 ? N ? 22

    SciTech Connect (OSTI)

    Hansen, Klavs [Department of Physics, University of Gothenburg, 41296 Gothenburg (Sweden); Li, Yejun; Kaydashev, Vladimir; Janssens, Ewald [Laboratory of Solid State Physics and Magnetism, KU Leuven, B-3001 Leuven (Belgium)

    2014-07-14T23:59:59.000Z

    The thermal radiation from small, laser heated, positively charged niobium clusters has been measured. The emitted power was determined by the quenching effect on the metastable decay, employing two different experimental protocols. The radiative power decreases slightly with cluster size and shows no strong size-to-size variations. The magnitude is 40–50 keV/s at the timescale of several microseconds, which is the measured crossover time from evaporative to radiative cooling.

  15. The effect of the number of wavebands used in spectral radiation heat transfer calculations

    SciTech Connect (OSTI)

    Chang, S. L.; Golchert, B.; Petrick, M.

    2000-05-09T23:59:59.000Z

    A spectral radiation heat transfer model that conserves emitted and absorbed energy has been developed and used to model the combustion space of an industrial glass furnace. This comprehensive radiation heat transfer model coupled with a computational fluid dynamics (CFD) code was used to investigate the effect of spectral dependencies on the computed results. The results of this work clearly indicate the need for a spectral approach as opposed to a gray body approach since the gray body approach (one waveband) severely underestimates the energy emitted via radiation.

  16. 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:

  17. Radiation Heat Transfer in Particle-Laden Gaseous Flame: Flame Acceleration and Triggering Detonation

    E-Print Network [OSTI]

    Liberman, M A; Kiverin, A D

    2015-01-01T23:59:59.000Z

    In this study we examine influence of the radiation heat transfer on the combustion regimes in the mixture, formed by suspension of fine inert particles in hydrogen gas. The gaseous phase is assumed to be transparent for the thermal radiation, while the radiant heat absorbed by the particles is then lost by conduction to the surrounding gas. The particles and gas ahead of the flame is assumed to be heated by radiation from the original flame. It is shown that the maximum temperature increase due to the radiation preheating becomes larger for a flame with lower velocity. For a flame with small enough velocity temperature of the radiation preheating may exceed the crossover temperature, so that the radiation heat transfer may become a dominant mechanism of the flame propagation. In the case of non-uniform distribution of particles, the temperature gradient formed due to the radiation preheating can initiate either deflagration or detonation ahead of the original flame via the Zel'dovich's gradient mechanism. Th...

  18. 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

    An experimental study concerned with different modes of heal transfer in fibrous and cellulose insulating material is presented. A series of experiments were conducted using an attic simulator to determine the effects of ventilation on attic heat...

  19. 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...

  20. 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.

  1. Energy levels, radiative rates and electron impact excitation rates for transitions in C III

    E-Print Network [OSTI]

    Aggarwal, K M

    2015-01-01T23:59:59.000Z

    We report energy levels, radiative rates (A-values) and lifetimes for the astrophysically-important Be-like ion C III. For the calculations, 166 levels belonging to the $n \\le$ 5 configurations are considered and the {\\sc grasp} (General-purpose Relativistic Atomic Structure Package) is adopted. Einstein A-coefficients are provided for all E1, E2, M1 and M2 transitions, while lifetimes are compared with available measurements as well as theoretical results, and no large discrepancies noted. Our energy levels are assessed to be accurate to better than 1\\% for a majority of levels, and A-values to better than 20\\% for most transitions. Collision strengths are also calculated, for which the Dirac Atomic R-matrix Code ({\\sc darc}) is used. A wide energy range, up to 21 Ryd, is considered and resonances resolved in a fine energy mesh in the thresholds region. The collision strengths are subsequently averaged over a Maxwellian velocity distribution to determine effective collision strengths up to a temperature of 8...

  2. Heat transfer including radiation and slag particles evolution in MHD channel-I

    SciTech Connect (OSTI)

    Im, K.H.; Ahluwalia, R.K.

    1980-01-01T23:59:59.000Z

    Accurate estimates of convective and radiative heat transfer in the magnetohydrodynamic channel are provided. Calculations performed for a base load-size channel indicate that heat transfer by gas radiation almost equals that by convection for smooth walls, and amounts to 70% as much as the convective heat transfer for rough walls. Carbon dioxide, water vapor, and potassium atoms are the principal participating gases. The evolution of slag particles by homogeneous nucleation and condensation is also investigated. The particle-size spectrum so computed is later utilized to analyze the radiation enhancement by slag particles in the MHD diffuser. The impact of the slag particle spectrum on the selection of a workable and design of an efficient seed collection system is discussed.

  3. 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.

  4. Difference between radiative transition rates in atoms and antiatoms

    E-Print Network [OSTI]

    Dolgov, A D; Rudenko, A S

    2012-01-01T23:59:59.000Z

    We demonstrate that CP violation results in a difference of the partial decay rates of atoms and antiatoms. The magnitude of this difference is estimated.

  5. Difference between radiative transition rates in atoms and antiatoms

    E-Print Network [OSTI]

    A. D. Dolgov; I. B. Khriplovich; A. S. Rudenko

    2012-08-17T23:59:59.000Z

    We demonstrate that CP violation results in a difference of the partial decay rates of atoms and antiatoms. The magnitude of this difference is estimated.

  6. 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.

  7. 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.

  8. Nonlocal study of the near field radiative heat transfer between two n-doped semiconductors

    E-Print Network [OSTI]

    Singer, F; Joulain, Karl

    2015-01-01T23:59:59.000Z

    We study in this work the near-field radiative heat transfer between two semi-infinite parallel planes of highly n-doped semiconductors. Using a nonlocal model of the dielectric permittivity, usually used for the case of metallic planes, we show that the radiative heat transfer coefficientsaturates as the separation distance is reduced for high doping concentration. These results replace the 1/d${}^2$ infinite divergence obtained in the local model case. Different features of the obtained results are shown to relate physically to the parameters of the materials, mainly the doping concentration and the plasmon frequency.

  9. 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.

  10. The role of radiation transport in the thermal response of semitransparent materials to localized laser heating

    SciTech Connect (OSTI)

    Colvin, Jeffrey; Shestakov, Aleksei; Stoelken, James; Vignes, Ryan [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551 (United States)

    2011-03-01T23:59:59.000Z

    Lasers are widely used to modify the internal structure of semitransparent materials for a wide variety of applications, including waveguide fabrication and laser glass damage healing. The gray diffusion approximation used in past models to describe radiation cooling is not adequate for these materials, particularly near the heated surface layer. In this paper we describe a computational model based upon solving the radiation transport equation in 1D by the P{sub n} method with {approx}500 photon energy bands, and by multi-group radiation diffusion in 2D with fourteen photon energy bands. The model accounts for the temperature-dependent absorption of infrared laser light and subsequent redistribution of the deposited heat by both radiation and conductive transport. We present representative results for fused silica irradiated with 2-12 W of 4.6 or 10.6 {mu}m laser light for 5-10 s pulse durations in a 1 mm spot, which is small compared to the diameter and thickness of the silica slab. We show that, unlike the case for bulk heating, in localized infrared laser heating radiation transport plays only a very small role in the thermal response of silica.

  11. 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., ...

  12. 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.

  13. ARM - Publications: Science Team Meeting Documents: Radiative Heating

    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 for4,645U.S. DOE Office of ScienceandMesa-Anomalous Radiative AbsorptionARM InArctic Facilityand Newand thewith the

  14. A parametric study of the source rate for outer radiation belt electrons using a Kalman filter

    E-Print Network [OSTI]

    Li, Xinlin

    A parametric study of the source rate for outer radiation belt electrons using a Kalman filter Q increasingly popular to describe the outer radiation belt energetic electron environment. We use a Kalman included. We augment the Kalman filter to include the intensity of local acceleration in the state vector

  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. Energy levels, radiative rates, and electron impact excitation rates for transitions in Li-like ions with 21?Z?28

    SciTech Connect (OSTI)

    Aggarwal, Kanti M., E-mail: K.Aggarwal@qub.ac.uk; Keenan, Francis P.

    2012-11-15T23:59:59.000Z

    We report calculations of energy levels, radiative rates, and electron impact excitation rates for transitions in Li-like ions with 21?Z?28. The General-Purpose Relativistic Atomic Structure Package is adopted for calculating energy levels and radiative rates, while for determining the collision strengths and subsequently the excitation rates, the Dirac Atomic R-matrix Code is used. Oscillator strengths, radiative rates, and line strengths are listed for all E1, E2, M1, and M2 transitions among the lowest 24 levels of the Li-like ions considered. Collision strengths have been averaged over a Maxwellian velocity distribution, and the effective collision strengths obtained are given over a wide temperature range up to 10{sup 7.8} K. Additionally, lifetimes are listed for all calculated levels of these ions. Finally, extensive comparisons are made with results available in the literature, as well as with our analogous calculations for all parameters with the Flexible Atomic Code, in order to assess the accuracy of the results.

  18. Energy levels, radiative rates, and electron impact excitation rates for transitions in Li-like ions with 12?Z?20

    SciTech Connect (OSTI)

    Aggarwal, Kanti M., E-mail: K.Aggarwal@qub.ac.uk; Keenan, Francis P.

    2013-03-15T23:59:59.000Z

    We report calculations of energy levels, radiative rates, and electron impact excitation rates for transitions in Li-like ions with 12?Z?20. The GRASP (general-purpose relativistic atomic structure package) is adopted for calculating energy levels and radiative rates, while for determining the collision strengths and subsequently the excitation rates, the Dirac atomic R-matrix code is used. Oscillator strengths, radiative rates, and line strengths are reported for all E1, E2, M1, and M2 transitions among the lowest 24 levels of the Li-like ions considered. Collision strengths have been averaged over a Maxwellian velocity distribution, and the effective collision strengths obtained are reported over a wide temperature range up to 10{sup 7.4} K. Additionally, lifetimes are also listed for all calculated levels of the ions. Finally, extensive comparisons are made with results available in the literature, as well as with our parallel calculations for all parameters with the Flexible Atomic Code, in order to assess the accuracy of the reported results.

  19. Homogenization of a Conductive, Convective and Radiative Heat Transfer Problem in a Heterogeneous Domain

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    -cooled reactor. It is typically made of many prismatic blocks of graphite in which are inserted the nuclear fuel in the homogenization of heat transfer in periodic porous media where the fluid part is made of long thin parallel in the solid part of the domain and by conduction, convection and radiative transfer in the fluid part (the

  20. Black carbon radiative heating effects on cloud microphysics and implications for the aerosol indirect

    E-Print Network [OSTI]

    Nenes, Athanasios

    thought. 1. Introduction Black Carbon (BC) has important effects on climate, owing to its ability of Technology, Pasadena, California, 91125, USA Abstract. This work examines the effect of black carbon (BC) radiative heating on cloud droplet formation. Changes in cloud droplet concentration and cloud albedo due

  1. Lecture 3 week 2/3 2012: Solar radiation, the greenhouse, global heat engine

    E-Print Network [OSTI]

    ....cycles of cold and warm climate. Averaged over the globe, sunlight falling on Earth in July (aphelion) is indeedLecture 3 week 2/3 2012: H 222c Solar radiation, the greenhouse, global heat engine http://en.wikipedia.org/ #12;#12;The 3 streams of this course (see syllabus) 1.Energy forms of energy concentrated, dilute

  2. PARALLEL COMPUTATIONS OF RADIATIVE HEAT TRANSFER USING THE DISCRETE ORDINATES METHOD

    E-Print Network [OSTI]

    Utah, University of

    of the important radiatively active species (CO2, H2O, soot) and temperature, which are calculated on the spatially increasingly tractable. Issues relating to the use of high-performance computing in participating media heat properties. First we summarize previous applications of spatial decomposition strategies to finite

  3. Radiation-induced chromosomal aberrations at different dose-rates

    E-Print Network [OSTI]

    McDaniel, Jackson Dean

    1965-01-01T23:59:59.000Z

    and sincere gratitude to Dr. G. M. Krise, for his advice and generosity, and to Dr. S. 0. Brown, for his vigilance throughout the course of this investigaticn. To Dr. H. R. Crookshank, I would like to acknowledge my indebtedness for serving as a sember... testicular cells eight hours postirradiation in animals given a total-body dose of 300 r at various dose rates . ; . . . . . . . . . . . , . . . . . . . . . . 17 II. Percentage of cells with aberrations per total dividing cells in the rat testes eight...

  4. -Improved estimates of incident radiation and heat load -751 Journal of Vegetation Science 18: 751-754, 2007

    E-Print Network [OSTI]

    McCune, Bruce

    as predictors. Heat load was calculated as a 45 degree rotation of the PDIR response surface. Results- Improved estimates of incident radiation and heat load - 751 Journal of Vegetation Science 18 regression (NPMR) improve estimates of potential direct incident radia- tion (PDIR) and heat load based

  5. Heating and cooling of a two-dimensional electron gas by terahertz radiation

    SciTech Connect (OSTI)

    Budkin, G. V.; Tarasenko, S. A., E-mail: tarasenko@coherent.ioffe.ru [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation)

    2011-04-15T23:59:59.000Z

    The absorption of terahertz radiation by free charge carriers in n-type semiconductor quantum wells accompanied by the interaction of electrons with acoustic and optical phonons is studied. It is shown that intrasubband optical transitions can cause both heating and cooling of the electron gas. The cooling of charge carriers occurs in a certain temperature and radiation frequency region where light is most efficiently absorbed due to intrasubband transitions with emission of optical phonons. In GaAs quantum wells, the optical cooling of electrons occurs most efficiently at liquid nitrogen temperatures, while cooling is possible even at room temperature in GaN heterostructures.

  6. The radiative heat transfer between a rotating nanoparticle and a plane surface

    E-Print Network [OSTI]

    Vahid Ameri; Mehdi Shafei Aporvari; Fardin Kheirandish

    2015-06-03T23:59:59.000Z

    Based on a microscopic approach, we propose a Lagrangian for the combined system of a rotating dielectric nanoparticle above a plane surface in the presence of electromagnetic vacuum fluctuations. In the framework of canonical quantization, the electromagnetic vacuum field is quantized in the presence of dielectric fields describing the nanoparticle and a semi-infinite dielectric with planar interface. The radiative heat power absorbed by the rotating nanoparticle is obtained and the result is in agreement with previous results when the the rotational frequency of the nanoparticle is zero or much smaller than the relaxation frequency of the dielectrics. The well known near field effect is reexamined and discussed in terms of the rotational frequency. The radiative heat power absorbed by the nanoparticle for well-known peak frequencies, is plotted in terms of the rotational frequency showing an interesting effect resembling a phase transition around a critical frequency, determined by the relaxation frequency of the dielectrics.

  7. A parametric study of shock jump chemistry, electron temperature, and radiative heat transfer models in hypersonic flows 

    E-Print Network [OSTI]

    Greendyke, Robert Brian

    1988-01-01T23:59:59.000Z

    will examine the radiance model and various step models in order to determine their appropriateness to the flight regime of the AOTV. The final area to be investigated will be the effect of nonequilibrium corrections on the radiative heat transfer models... of T and e T will be valid as long as there is a reasonable amount vNs of nitrogen molecules in the flow. Radiative Heat Transfer Models For this study, four radiative heat transfer models were examined. One of these models is an optically thin radiance...

  8. Final Technical Report for "Radiative Heating Associated with Tropical Convective Cloud Systems: Its Importance at Meso and Global Scales"

    SciTech Connect (OSTI)

    Schumacher, Courtney

    2012-12-13T23:59:59.000Z

    Heating associated with tropical cloud systems drive the global circulation. The overall research objectives of this project were to i) further quantify and understand the importance of heating in tropical convective cloud systems with innovative observational techniques, and ii) use global models to determine the large-scale circulation response to variability in tropical heating profiles, including anvil and cirrus cloud radiative forcing. The innovative observational techniques used a diversity of radar systems to create a climatology of vertical velocities associated with the full tropical convective cloud spectrum along with a dissection of the of the total heating profile of tropical cloud systems into separate components (i.e., the latent, radiative, and eddy sensible heating). These properties were used to validate storm-scale and global climate models (GCMs) and were further used to force two different types of GCMs (one with and one without interactive physics). While radiative heating was shown to account for about 20% of the total heating and did not have a strong direct response on the global circulation, the indirect response was important via its impact on convection, esp. in how radiative heating impacts the tilt of heating associated with the Madden-Julian Oscillation (MJO), a phenomenon that accounts for most tropical intraseasonal variability. This work shows strong promise in determining the sensitivity of climate models and climate processes to heating variations associated with cloud systems.

  9. Radiative Heating of the ISCCP Upper Level Cloud Regimes and its Impact on the Large-scale Tropical Circulation

    SciTech Connect (OSTI)

    Li, Wei; Schumacher, Courtney; McFarlane, Sally A.

    2013-01-31T23:59:59.000Z

    Radiative heating profiles of the International Satellite Cloud Climatology Project (ISCCP) cloud regimes (or weather states) were estimated by matching ISCCP observations with radiative properties derived from cloud radar and lidar measurements from the Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) sites at Manus, Papua New Guinea, and Darwin, Australia. Focus was placed on the ISCCP cloud regimes containing the majority of upper level clouds in the tropics, i.e., mesoscale convective systems (MCSs), deep cumulonimbus with cirrus, mixed shallow and deep convection, and thin cirrus. At upper levels, these regimes have average maximum cloud occurrences ranging from 30% to 55% near 12 km with variations depending on the location and cloud regime. The resulting radiative heating profiles have maxima of approximately 1 K/day near 12 km, with equal heating contributions from the longwave and shortwave components. Upper level minima occur near 15 km, with the MCS regime showing the strongest cooling of 0.2 K/day and the thin cirrus showing no cooling. The gradient of upper level heating ranges from 0.2 to 0.4 K/(day?km), with the most convectively active regimes (i.e., MCSs and deep cumulonimbus with cirrus) having the largest gradient. When the above heating profiles were applied to the 25-year ISCCP data set, the tropics-wide average profile has a radiative heating maximum of 0.45Kday-1 near 250 hPa. Column-integrated radiative heating of upper level cloud accounts for about 20% of the latent heating estimated by the Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR). The ISCCP radiative heating of tropical upper level cloud only slightly modifies the response of an idealized primitive equation model forced with the tropics-wide TRMM PR latent heating, which suggests that the impact of upper level cloud is more important to large-scale tropical circulation variations because of convective feedbacks rather than direct forcing by the cloud radiative heating profiles. However, the height of the radiative heating maxima and gradient of the heating profiles are important to determine the sign and patterns of the horizontal circulation anomaly driven by radiative heating at upper levels.

  10. Comparison of Simulated and Observed Continental Tropical Anvil Clouds and Their Radiative Heating Profiles

    SciTech Connect (OSTI)

    Powell, Scott W.; Houze, R.; Kumar, Anil; McFarlane, Sally A.

    2012-09-06T23:59:59.000Z

    Vertically pointing millimeter-wavelength radar observations of anvil clouds extending from mesoscale convective systems (MCSs) that pass over an Atmospheric Radiation Measurement Program (ARM) field site in Niamey, Niger, are compared to anvil structures generated by the Weather Research and Forecasting (WRF) mesoscale model using six different microphysical schemes. The radar data provide the statistical distribution of the radar reflectivity values as a function of height and anvil thickness. These statistics are compared to the statistics of the modeled anvil cloud reflectivity at all altitudes. Requiring the model to be statistically accurate at all altitudes is a stringent test of the model performance. The typical vertical profile of radiative heating in the anvil clouds is computed from the radar observations. Variability of anvil structures from the different microphysical schemes provides an estimate of the inherent uncertainty in anvil radiative heating profiles. All schemes underestimate the optical thickness of thin anvils and cirrus, resulting in a bias of excessive net anvil heating in all of the simulations.

  11. Effects of gamma radiation on Serratia marcescens; a comparison of effects of two different exposure rates

    E-Print Network [OSTI]

    Moore, Christy Annette

    1972-01-01T23:59:59.000Z

    EFFECTS OF GAMMA RADIATION ON SL'RNATIA MARCESCENS A COMPARISON OF EFFECTS OF TWO DIFFERENT EXPOSURE RATES A Thesis by CHRISTY ANNETTE MOORE Submitted to the Graduate College of Texas ARM University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE December 1972 Major Subject: Biophysics (Health Physics) EFFECTS OF GAMF'K RADIATION ON O'Eccrid?2;!, 'i&Lo"", C, . ij, ", A COMFARISON OF EFFECTS OF TNO DIFFERENT EYPO s KE RATES A Thea's CHRISTi ANNETTE MOORE Approved...

  12. Parametric analysis of radiative-convective heat transfer around a circular cylinder in a cross flow using the finite volume radiation solution method

    SciTech Connect (OSTI)

    Lee, K.H.; Lee, J.S.; Choi, M. [Seoul National Univ. (Korea, Republic of). Dept. of Mechanical Engineering

    1996-02-09T23:59:59.000Z

    In the outside vapor deposition (OVD) process, silica particles are deposited by thermophoretic force on the surface of a cylinder. This process is associated with complex physical phenomena such as heat transfer between a torch and a cylinder, chemical reaction for silica particle formation, and particle deposition. Since the OVD process is carried out in a very high temperature environment, radiative heat transfer should be taken into consideration. Here, the radiative-convective heat transfer around a circular cylinder in a cross flow of a radiating gas has been numerically analyzed using the finite volume radiation solution method in a nonorthogonal coordinate system. The cross-flow Reynolds number based on the cylinder diameter is 40, and the fluid Prandtl number is assumed to be 0.7. The radiative heat transfer coupled with convection is reasonably predicted by the finite volume radiation solution method. Distributions of the local Nusselt number are investigated according to the variation of radiation parameters such as conduction-to-radiation parameter, optical thickness, scattering albedo, and cylinder wall emissivity.

  13. Friedmann-like collapsing model of a radiating sphere with heat flow

    SciTech Connect (OSTI)

    Kolassis, C.A.; Santos, N.O.; Tsoubelis, D.

    1988-04-01T23:59:59.000Z

    This paper considers a spherical body consisting of a fluid with heat flow which radiates in its exterior a null fluid described by the outgoing Vaidya's metric. A Friedmann-like exact solution of the interior Einstein field equations is given. It is proved that this solution, matched with the outgoing Vaidya matric, represents a physically reasonble collapsing model which, when the heat flow is switched off, reduces to the well-known collapsing model with dust. The proposed model has the remarkable property that even if the heat flow is small, the horizon will never be formed because, before this happens, the collapsing body will be destroyed by opposite gradients of pressure. 6 references.

  14. RADIATION HEAT TRANSFER ENVIRONMENT IN FIRE AND FURNACE TESTS OF RADIOACTIVE MATERIALS PAKCAGES

    SciTech Connect (OSTI)

    Smith, A

    2008-12-31T23:59:59.000Z

    The Hypothetical Accident Conditions (HAC) sequential test of radioactive materials packages includes a thermal test to confirm the ability of the package to withstand a transportation fire event. The test specified by the regulations (10 CFR 71) consists of a 30 minute, all engulfing, hydrocarbon fuel fire, with an average flame temperature of at least 800 C. The requirements specify an average emissivity for the fire of at least 0.9, which implies an essentially black radiation environment. Alternate test which provide equivalent total heat input at the 800 C time averaged environmental temperature may also be employed. When alternate tests methods are employed, such as furnace or gaseous fuel fires, the equivalence of the radiation environment may require justification. The effects of furnace and open confinement fire environments are compared with the regulatory fire environment, including the effects of gases resulting from decomposition of package overpack materials. The results indicate that furnace tests can produce the required radiation heat transfer environment, i.e., equivalent to the postulated pool fire. An open enclosure, with transparent (low emissivity) fire does not produce an equivalent radiation environment.

  15. 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.

  16. Multi-level effects of low dose rate ionizing radiation on southern toad, Anaxyrus [Bufo] terrestris

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

    Stark, Karolina; Scott, David E.; Tsyusko, Olga; Coughlin, Daniel P.; Hinton, Thomas G.; Amendola, Roberto

    2015-04-30T23:59:59.000Z

    Despite their potential vulnerability to contaminants from exposure at multiple life stages, amphibians are one of the least studied groups of vertebrates in ecotoxicology, and research on radiation effects in amphibians is scarce. We used multiple endpoints to assess the radiosensitivity of the southern toad (Anaxyrus [Bufo] terrestris) during its pre-terrestrial stages of development –embryonic, larval, and metamorphic. Toads were exposed, from several hours after oviposition through metamorphosis (up to 77 days later), to four low dose rates of ¹³?Cs at 0.13, 2.4, 21, and 222 mGy d?¹, resulting in total doses up to 15.8 Gy. Radiation treatments did notmore »affect hatching success of embryos, larval survival, or the length of the larval period. The individual family variation in hatching success of embryos was larger than the radiation response. In contrast, newly metamorphosed individuals from the higher dose-rate treatments had higher mass and mass/length body indices, a measure which may relate to higher post-metamorphic survival. The increased mass and index at higher dose rates may indicate that the chronic, low dose rate radiation exposures triggered secondary responses. Additionally, the increases in growth were linked to a decrease in DNA damage (as measured by the Comet Assay) in red blood cells at a dose rate of 21mGy d?¹ and a total dose of 1.1 Gy. In conclusion, the complex effects of low dose rates of ionizing radiation may trigger growth and cellular repair mechanisms in amphibian larvae.« less

  17. Multi-level effects of low dose rate ionizing radiation on southern toad, Anaxyrus [Bufo] terrestris

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

    Stark, Karolina [Stockholm Univ. (Sweden); Univ. of Georgia, Aiken, SC (United States); Scott, David E. [Univ. of Georgia, Aiken, SC (United States); Tsyusko, Olga [Univ. of Georgia, Aiken, SC (United States); Univ. of Kentucky, Lexington, KY (United States); Coughlin, Daniel P. [Univ. of Georgia, Aiken, SC (United States); Hinton, Thomas G. [Univ. of Georgia, Aiken, SC (United States); Inst. of Radiation Protection and Nuclear Safety, Cadarache (France); Amendola, Roberto [ENEA, (Italy)

    2015-04-30T23:59:59.000Z

    Despite their potential vulnerability to contaminants from exposure at multiple life stages, amphibians are one of the least studied groups of vertebrates in ecotoxicology, and research on radiation effects in amphibians is scarce. We used multiple endpoints to assess the radiosensitivity of the southern toad (Anaxyrus [Bufo] terrestris) during its pre-terrestrial stages of development –embryonic, larval, and metamorphic. Toads were exposed, from several hours after oviposition through metamorphosis (up to 77 days later), to four low dose rates of ¹³?Cs at 0.13, 2.4, 21, and 222 mGy d?¹, resulting in total doses up to 15.8 Gy. Radiation treatments did not affect hatching success of embryos, larval survival, or the length of the larval period. The individual family variation in hatching success of embryos was larger than the radiation response. In contrast, newly metamorphosed individuals from the higher dose-rate treatments had higher mass and mass/length body indices, a measure which may relate to higher post-metamorphic survival. The increased mass and index at higher dose rates may indicate that the chronic, low dose rate radiation exposures triggered secondary responses. Additionally, the increases in growth were linked to a decrease in DNA damage (as measured by the Comet Assay) in red blood cells at a dose rate of 21mGy d?¹ and a total dose of 1.1 Gy. In conclusion, the complex effects of low dose rates of ionizing radiation may trigger growth and cellular repair mechanisms in amphibian larvae.

  18. A parametric study of shock jump chemistry, electron temperature, and radiative heat transfer models in hypersonic flows

    E-Print Network [OSTI]

    Greendyke, Robert Brian

    1988-01-01T23:59:59.000Z

    A PARAMETRIC STUDY OF SHOCK JUMP CHEMISTRY, ELECTRON TEMPERATURE, AND RADIATIVE HEAT TRANSFER MODELS IN HYPERSONIC FLOWS A Thesis by ROBERT BRIAN GREENDYKE Submitted to the Graduate College of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE August 1988 Major Subject: Aerospace Engineering A PARAMETRIC STUDY OF SHOCK JUMP CHEMISTRY, ELECTRON TEMPERATURE, AND RADIATIVE HEAT TRANSFER MODELS IN HYPERSONIC FLOWS A Thesis by ROBERT BRIAN...

  19. Radiation and Reason Why radiation at modest dose rates is quite harmless and current radiation safety regulations are flawed

    E-Print Network [OSTI]

    CERN. Geneva

    2013-01-01T23:59:59.000Z

    Data on the impact of ionising radiation on life are examined in the light of evolutionary biology. This comparison confirms that fear of nuclear radiation is not justified by science itself; rather it originates in a failure of public trust in nuclear science, a relic of the international politics of the Cold War era. Current ionisation safety regulations appease this fear but without scientific support and they need fundamental reformulation. This should change the reaction to accidents like Fukushima, the cost of nuclear energy and the application of nuclear technology to the supply of food and fresh water. Such a boost to the world economy would require that more citizens study and appreciate the science involved – and then tell others -- not as much fun as the Higgs, perhaps, but no less important! www.radiationandreason.com

  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. Radiation bronchitis and stenosis secondary to high dose rate endobronchial irradiation

    SciTech Connect (OSTI)

    Speiser, B.L. (St. Joseph's Hospital and Medical Center, Phoenix, AZ (United States)); Spratling, L.

    1993-03-15T23:59:59.000Z

    The purpose of the study was to describe a new clinical entity observed in follow-up bronchoscopies in patients who were treated with high dose rate and medium dose rate remote afterloading brachytherapy of the tracheobronchial tree. Patients were treated by protocol with medium dose rate, 47 patients receiving 1000 cGy at a 5 mm depth times three fractions, high dose rate 144 patients receiving 1000 cGy at a 10 mm depth for three fractions and high dose rate 151 patients receiving cGy at a 10 mm depth for three fractions followed by bronchoscopy. Incidence of this entity was 9% for the first group, 12% for the second, and 13% for the third group. Reactions were grade 1 consisting of mild inflammatory response with a partial whitish circumferential membrane in an asymptomatic patient; grade 2, thicker complete white circumferential membrane with cough and/or obstructive problems requiring intervention; grade 3, severe inflammatory response with marked membranous exudate and mild fibrotic reaction; and grade 4 a predominant fibrotic reaction with progressive stenosis. Variables associated with a slightly increased incidence of radiation bronchitis and stenosis included: large cell carcinoma histology, curative intent, prior laser photoresection, and/or concurrent external radiation. Survival was the strongest predictor of the reaction. Radiation bronchitis and stenosis is a new clinical entity that must be identified in bronchial brachytherapy patients and treated appropriately. 23 refs., 3 figs., 7 tabs.

  2. Direct and sequential radiative three-body reaction rates at low temperatures

    E-Print Network [OSTI]

    E. Garrido; R. de Diego; D. V. Fedorov; A. S. Jensen

    2011-08-24T23:59:59.000Z

    We investigate the low-temperature reaction rates for radiative capture processes of three particles. We compare direct and sequential capture mechanisms and rates using realistic phenomenological parametrizations of the corresponding photodissociation cross sections.Energy conservation prohibits sequential capture for energies smaller than that of the intermediate two-body structure. A finite width or a finite temperature allows this capture mechanism. We study generic effects of positions and widths of two- and three-body resonances for very low temperatures. We focus on nuclear reactions relevant for astrophysics, and we illustrate with realistic estimates for the $\\alpha$-$\\alpha$-$\\alpha$ and $\\alpha$-$\\alpha$-$n$ radiative capture processes. The direct capture mechanism leads to reaction rates which for temperatures smaller than 0.1 GK can be several orders of magnitude larger than those of the NACRE compilation.

  3. Eurotherm Seminar N81 Reactive Heat Transfer in Porous Media, Ecole des Mines d'Albi, France June 4-6, 2007 ET81-1 HEAT TRANSFER BY SIMULTANEOUS RADIATION-CONDUCTION

    E-Print Network [OSTI]

    Boyer, Edmond

    Eurotherm Seminar N°81 Reactive Heat Transfer in Porous Media, Ecole des Mines d'Albi, France June 4-6, 2007 ET81- 1 HEAT TRANSFER BY SIMULTANEOUS RADIATION-CONDUCTION AND CONVECTION IN A HIGH for the packed bed. The comparison between the radiative heat transfer and the exchanges by conduction and forced

  4. Electromagnetic Radiation in Hot QCD Matter: Rates, Electric Conductivity, Flavor Susceptibility and Diffusion

    E-Print Network [OSTI]

    Chang-Hwan Lee; Ismail Zahed

    2014-03-07T23:59:59.000Z

    We discuss the general features of the electromagnetic radiation from a thermal hadronic gas as constrained by chiral symmetry. The medium effects on the electromagnetic spectral functions and the partial restoration of chiral symmetry are quantified in terms of the pion densities. The results are compared with the electromagnetic radiation from a strongly interacting quark-gluon plasma in terms of the leading gluon condensate operators. We use the spectral functions as constrained by the emission rates to estimate the electric conductivity, the light flavor susceptibility and diffusion constant across the transition from the correlated hadronic gas to a strongly interacting quark-gluon plasma.

  5. Radiation heat transfer in multitube, alkaline-metal thermal-to-electric converter

    SciTech Connect (OSTI)

    Tournier, J.M.P.; El-Genk, M.S. [Univ. of New Mexico, Albuquerque, NM (United States)

    1999-02-01T23:59:59.000Z

    Vapor anode, multitube Alkali-Metal Thermal-to-Electric Converters (AMTECs) are being considered for a number of space missions, such as the NASA Pluto/Express (PX) and Europa missions, scheduled for the years 2004 and 2005, respectively. These static converters can achieve a high fraction of Carnot efficiency at relatively low operating temperatures. An optimized cell can potentially provide a conversion efficiency between 20 and 30 percent, when operated at a hot-side temperature of 1000--1200 K and a cold-side temperature of 550--650 K. A comprehensive modeling and testing program of vapor anode, multitube AMTEC cells has been underway for more than three years at the Air Force Research Laboratory`s Power and Thermal Group (AFRL/VSDVP), jointly with the University of New Mexico`s Institute for Space and Nuclear Power Studies. The objective of this program is to demonstrate the readiness of AMTECs for flight on future US Air Force space missions. A fast, integrated AMTEC Performance and Evaluation Analysis Model (APEAM) has been developed to support ongoing vacuum tests at AFRL and perform analyses and investigate potential design changes to improve the PX-cell performance. This model consists of three major components (Tournier and El-Genk 1998a, b): (a) a sodium vapor pressure loss model, which describes continuum, transition and free-molecule flow regimes in the low-pressure cavity of the cell; (b) an electrochemical and electrical circuit model; and (c) a radiation/conduction heat transfer model, for calculating parasitic heat losses. This Technical Note describes the methodology used to calculate the radiation view factors within the enclosure of the PX-cells, and the numerical procedure developed in this work to determine the radiation heat transport and temperatures within the cell cavity.

  6. Radiative heat transfer between two dielectric nanogratings in the scattering approach

    E-Print Network [OSTI]

    J. Lussange; R. Guérout; F. S. S. Rosa; J. -J. Greffet; A. Lambrecht; S. Reynaud

    2012-06-01T23:59:59.000Z

    We present a theoretical study of radiative heat transfer between dielectric nanogratings in the scattering approach. As a comparision with these exact results, we also evaluate the domain of validity of Derjaguin's Proximity Approximation (PA). We consider a system of two corrugated silica plates with various grating geometries, separation distances, and lateral displacement of the plates with respect to one another. Numerical computations show that while the PA is a good approximation for aligned gratings, it cannot be used when the gratings are laterally displaced. We illustrate this by a thermal modulator device for nanosystems based on such a displacement.

  7. 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.

  8. 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.

  9. The rate constant for radiative association of HF: Comparing quantum and classical dynamics

    SciTech Connect (OSTI)

    Gustafsson, Magnus, E-mail: magngu@chem.gu.se; Monge-Palacios, M.; Nyman, Gunnar [Department of Chemistry and Molecular Biology, University of Gothenburg, 41296 Gothenburg (Sweden)] [Department of Chemistry and Molecular Biology, University of Gothenburg, 41296 Gothenburg (Sweden)

    2014-05-14T23:59:59.000Z

    Radiative association for the formation of hydrogen fluoride through the A{sup 1}? ? X{sup 1}?{sup +} and X{sup 1}?{sup +} ? X{sup 1}?{sup +} transitions is studied using quantum and classical dynamics. The total thermal rate constant is obtained for temperatures from 10 K to 20 000 K. Agreement between semiclassical and quantum approaches is observed for the A{sup 1}? ? X{sup 1}?{sup +} rate constant above 2000 K. The agreement is explained by the fact that the corresponding cross section is free of resonances for this system. At temperatures below 2000 K we improve the agreement by implementing a simplified semiclassical expression for the rate constant, which includes a quantum corrected pair distribution. The rate coefficient for the X{sup 1}?{sup +} ? X{sup 1}?{sup +} transition is calculated using Breit–Wigner theory and a classical formula for the resonance and direct contributions, respectively. In comparison with quantum calculations the classical formula appears to overestimate the direct contribution to the rate constant by about 12% for this transition. Below about 450 K the resonance contribution is larger than the direct, and above that temperature the opposite holds. The biggest contribution from resonances is at the lowest temperature in the study, 10 K, where it is more than four times larger than the direct. Below 1800 K the radiative association rate constant due to X{sup 1}?{sup +} ? X{sup 1}?{sup +} transitions dominates over A{sup 1}? ? X{sup 1}?{sup +}, while above that temperature the situation is the opposite.

  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. 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.

  12. 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...

  13. 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...

  14. 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.

  15. 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 ...

  16. Oxy-fuel combustion of coal and biomass, the effect on radiative and convective heat transfer and burnout

    SciTech Connect (OSTI)

    Smart, John P.; Patel, Rajeshriben; Riley, Gerry S. [RWEnpower, Windmill Hill Business Park, Whitehill Way, Swindon, Wiltshire SN5 6PB, England (United Kingdom)

    2010-12-15T23:59:59.000Z

    This paper focuses on results of co-firing coal and biomass under oxy-fuel combustion conditions on the RWEn 0.5 MWt Combustion Test Facility (CTF). Results are presented of radiative and convective heat transfer and burnout measurements. Two coals were fired: a South African coal and a Russian Coal under air and oxy-fuel firing conditions. The two coals were also co-fired with Shea Meal at a co-firing mass fraction of 20%. Shea Meal was also co-fired at a mass fraction of 40% and sawdust at 20% with the Russian Coal. An IFRF Aerodynamically Air Staged Burner (AASB) was used. The thermal input was maintained at 0.5 MWt for all conditions studied. The test matrix comprised of varying the Recycle Ratio (RR) between 65% and 75% and furnace exit O{sub 2} was maintained at 3%. Carbon-in-ash samples for burnout determination were also taken. Results show that the highest peak radiative heat flux and highest flame luminosity corresponded to the lowest recycle ratio. The effect of co-firing of biomass resulted in lower radiative heat fluxes for corresponding recycle ratios. Furthermore, the highest levels of radiative heat flux corresponded to the lowest convective heat flux. Results are compared to air firing and the air equivalent radiative and convective heat fluxes are fuel type dependent. Reasons for these differences are discussed in the main text. Burnout improves with biomass co-firing under both air and oxy-fuel firing conditions and burnout is also seen to improve under oxy-fuel firing conditions compared to air. (author)

  17. 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...

  18. Gauge independence of the bubble nucleation rate in theories with radiative symmetry breaking

    SciTech Connect (OSTI)

    Metaxas, D.; Weinberg, E.J. [Department of Physics, Columbia University, New York, New York 10027 (United States)] [Department of Physics, Columbia University, New York, New York 10027 (United States)

    1996-01-01T23:59:59.000Z

    In field theories where a metastable false vacuum state arises as a result of radiative corrections, the calculation of the rate of false vacuum decay by bubble nucleation depends on the effective potential and the other functions that appear in the derivative expansion of the effective action. Beginning with the Nielsen identity, we derive a series of identities that govern the gauge dependence of these functions. Using these, we show, to leading nontrivial order, that, even though these functions are individually gauge dependent, one obtains a gauge-independent result for the bubble nucleation rate. Our formal arguments are complemented by explicit calculations for scalar electrodynamics in a class of {ital R}{sub {xi}} gauges. {copyright} {ital 1996 The American Physical Society.}

  19. Testing the improved method for calculating the radiation heat generation at the periphery of the BOR-60 reactor core

    SciTech Connect (OSTI)

    Varivtsev, A. V., E-mail: vav3@niiar.ru; Zhemkov, I. Yu. [JSC “SSC RIAR,” Dimitrovgrad-10 (Russian Federation)

    2014-12-15T23:59:59.000Z

    The application of the improved method for calculating the radiation heat generation in the elements of an experimental device located at the periphery of the BOR-60 reactor core results in a significant reduction in the discrepancies between the calculated and the experimental data. This allows us to conclude that the improved method has an advantage over the one used earlier.

  20. Performance of an LPD prototype detector at MHz frame rates under Synchrotron and FEL radiation

    E-Print Network [OSTI]

    Koch, Andreas; Nicholls, Tim; Angelsen, Christian; Coughlan, John; French, Marcus; Hauf, Steffen; Kuster, Markus; Sztuk-Dambietz, Jolanta; Turcato, Monica; Carini, Gabriella A; Chollet, Matthieu; Herrmann, Sven C; Lemke, Henrik T; Nelson, Silke; Song, Sanghoon; Weaver, Matt; Zhu, Diling; Meents, Alke; Fischer, Pontus

    2013-01-01T23:59:59.000Z

    A MHz frame rate X-ray area detector (LPD - Large Pixel Detector) is under development by the Rutherford Appleton Laboratory for the European XFEL. The detector will have 1 million pixels and allows analogue storage of 512 images taken at 4.5 MHz in the detector front end. The LPD detector has 500 mm thick silicon sensor tiles that are bump bonded to a readout ASIC. The ASICs preamplifier provides relatively low noise at high speed which results in a high dynamic range of 10^5 photons over an energy range of 5-20 keV. Small scale prototypes of 32x256 pixels (LPD 2-Tile detector) and 256x256 pixels (LPD supermodule detector) are now available for X-ray tests. The performance of prototypes of the detector is reported for first tests under synchrotron radiation (PETRA III at DESY) and Free-Electron-Laser radiation (LCLS at SLAC). The initial performance of the detector in terms of signal range and noise, radiation hardness and spatial and temporal response are reported. The main result is that the 4.5 MHz sampli...

  1. 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 ...

  2. The radiative capture reaction rate from $??$ to H dibaryon in the imaginary time method

    E-Print Network [OSTI]

    E. Hikota; Y. Funaki; E. Hiyama; M. Oka

    2015-05-08T23:59:59.000Z

    Radiative capture rates of thermal $\\Lambda\\Lambda + \\Xi$N states into H dibaryon are calculated in the novel imaginary time method. The H dibaryon is assumed to be a bound state of $\\Xi $N with spin $J^{\\pi}= 0^+$, isospin $I=0$ and strangeness $-2$. We consider $E1$ transition to H from $\\Xi$N $(L=1)$ scattering states which mix with $\\Lambda\\Lambda (L=1)$. In order to calculate the transition rates, we formulate a coupled-channel imaginary time method by extending the one-channel formula originally proposed by Yabana and Funaki. The imaginary time method allows us to avoid the sum over all the excited thermal initial states, and thus to save computational time significantly. The transition rates are given as a function of temperature and the unknown binding energy of the H dibaryon, which we take as a parameter. It is found that the transition rate is not sensitive to the choices of the H binding energy or the strengths of the channel coupling for temperatures 3 MeV or higher.

  3. 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.

  4. Variation in rectal temperature, respiratory rate, and pulse rate of cattle as related to variations in solar radiation, air temperature, wind velocity, and vapor pressure

    E-Print Network [OSTI]

    Quazi, Mohammad Fazlur Rahim

    1955-01-01T23:59:59.000Z

    VARIATION IN RECTAL TEMPERATURE, RESPIRATORY RATE, AND PULSE RATE GF CATTLE AS RELATED TO VARIATIONS IN SOLAR RADIATION, AIR TEMPERATURE, WIND VELOCITY, AND VAPOR PRESSURE A Dissertation By Mohammad Fazlur Rahim Quazi Approved as to style... Dissertation By Mohammad Fazlur Rahim tyiazi Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY May 1955 Major Subject: Genetics ? ?4...

  5. 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...

  6. 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

  7. Modeling near-field radiative heat transfer from sharp objects using a general 3d numerical scattering technique

    E-Print Network [OSTI]

    McCauley, Alexander P; Krüger, Matthias; Johnson, Steven G

    2011-01-01T23:59:59.000Z

    We examine the non-equilibrium radiative heat transfer between a plate and finite cylinders and cones, making the first accurate theoretical predictions for the total heat transfer and the spatial heat flux profile for three-dimensional compact objects including corners or tips. We find qualitatively different scaling laws for conical shapes at small separations, and in contrast to a flat/slightly-curved object, a sharp cone exhibits a local \\emph{minimum} in the spatially resolved heat flux directly below the tip. The method we develop, in which a scattering-theory formulation of thermal transfer is combined with a boundary-element method for computing scattering matrices, can be applied to three-dimensional objects of arbitrary shape.

  8. MicroShield analysis to calculate external radiation dose rates for several spent fuel casks

    SciTech Connect (OSTI)

    Marincel, M.K. [Missouri Univ., Rolla, MO (United States); Weiner, R.F.; Osborn, D.M. [Sandia National Laboratories, Albuquerque, NM (United States)

    2007-07-01T23:59:59.000Z

    The purpose of this MicroShield analysis is to calculate the external radiation, primarily gamma, dose rate for spent fuel casks. The reason for making this calculation is that currently all analyses of transportation risk assume that this external dose rate is the maximum allowed by regulation, 10 mrem/hr at 2 m from the casks, and the risks of incident-free transportation are thus always overestimated to an unknown extent. In order to do this, the program by Grove Software, MicroShield 7.01, was used to model three Nuclear Regulatory Commission (NRC) approved casks: HI-STAR 100, GA-4, and NAC-STC, loaded with specific source material. Dimensions were obtained from NUREG/CR-6672 and the Certificates of Compliance for each respective cask. Detectors were placed at the axial point at 1 m and 2 m from the outer gamma shielding of the casks. In the April 8, 2004 publication of the Federal Register, a notice of intent to prepare a Supplemental Yucca Mountain Environmental Impact Statement (DOE/EIS-0250F-S1) was published by the Office of Civilian Radioactive Waste Management (OCRWM) in order to consider design, construction, operation, and transportation of spent nuclear fuel to the Yucca Mountain repository [1]. These more accurate estimates of the external dose rates could be used in order to provide a more risk-informed analysis. (authors)

  9. 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.

  10. Magnetic-field control of near-field radiative heat transfer and the realization of highly tunable hyperbolic thermal emitters

    E-Print Network [OSTI]

    Moncada-Villa, Edwin; Garcia-Vidal, Francisco J; Garcia-Martin, Antonio; Cuevas, Juan Carlos

    2015-01-01T23:59:59.000Z

    We present a comprehensive theoretical study of the magnetic field dependence of the near-field radiative heat transfer (NFRHT) between two parallel plates. We show that when the plates are made of doped semiconductors, the near-field thermal radiation can be severely affected by the application of a static magnetic field. We find that irrespective of its direction, the presence of a magnetic field reduces the radiative heat conductance, and dramatic reductions up to 700% can be found with fields of about 6 T at room temperature. We show that this striking behavior is due to the fact that the magnetic field radically changes the nature of the NFRHT. The field not only affects the electromagnetic surface waves (both plasmons and phonon polaritons) that normally dominate the near-field radiation in doped semiconductors, but it also induces hyperbolic modes that progressively dominate the heat transfer as the field increases. In particular, we show that when the field is perpendicular to the plates, the semicond...

  11. Energy levels and radiative transition rates for Ge XXXI, As XXXII, and Se XXXIII

    SciTech Connect (OSTI)

    Aggarwal, Sunny, E-mail: sunny.du87@gmail.com; Singh, J.; Jha, A.K.S.; Mohan, Man

    2014-07-15T23:59:59.000Z

    Fine-structure energies of the 67 levels belonging to the 1s{sup 2}, 1s 2l, 1s3l, 1s4l, 1s5l, and 1s6l configurations of Ge XXXI, As XXXII, and Se XXXIII have been calculated using the General-Purpose Relativistic Atomic Structure Package. In addition, radiative rates, oscillator strengths, transition wavelengths, and line strengths have been calculated for all electric dipole, magnetic dipole, electric quadrupole, and magnetic quadrupole transitions among these levels. Lifetimes are also presented for all excited levels of these three ions. We have compared our results with the results available in the literature and the accuracy of the data is assessed. We predict new energy levels, oscillator strengths, and transition probabilities where no other theoretical or experimental results are available, which will form the basis for future experimental work.

  12. Energy levels, radiative rates and electron impact excitation rates for transitions in He-like Ga XXX, Ge XXXI, As XXXII, Se XXXIII and Br XXXIV

    E-Print Network [OSTI]

    Aggarwal, Kanti M

    2013-01-01T23:59:59.000Z

    We report calculations of energy levels, radiative rates and electron impact excitation cross sections and rates for transitions in He-like Ga XXX, Ge XXXI, As XXXII, Se XXXIII and Br XXXIV. The {\\sc grasp} (general-purpose relativistic atomic structure package) is adopted for calculating energy levels and radiative rates. For determining the collision strengths, and subsequently the excitation rates, the Dirac Atomic R-matrix Code ({\\sc darc}) is used. Oscillator strengths, radiative rates and line strengths are reported for all E1, E2, M1 and M2 transitions among the lowest 49 levels of each ion. Additionally, theoretical lifetimes are provided for all 49 levels of the above five ions. Collision strengths are averaged over a Maxwellian velocity distribution and the effective collision strengths obtained listed over a wide temperature range up to 10$^{8}$ K. Comparisons are made with similar data obtained using the Flexible Atomic Code ({\\sc fac}) to highlight the importance of resonances, included in calcul...

  13. 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.

  14. Impact of the Position of a Radiator to Energy Consumption and Thermal Comfort in a Mixed Radiant and Convective Heating System

    E-Print Network [OSTI]

    Gong, X.; Claridge, D. E.

    2005-01-01T23:59:59.000Z

    ESL-IC-10/05-35 1 Impact of the Position of the Radiator on Energy Consumption and Thermal Comfort in a Mixed Radiant and Convective Heating System Xiangyang Gong David E... the energy consumption and thermal comfort distribution in a typical office with a mixed radiant and convective heating system for two different locations of radiant heat sources. Accurately estimating the energy consumption in a mixed heating space...

  15. Impact of the Position of a Radiator to Energy Consumption and Thermal Comfort in a Mixed Radiant and Convective Heating System 

    E-Print Network [OSTI]

    Gong, X.; Claridge, D. E.

    2005-01-01T23:59:59.000Z

    ESL-IC-10/05-35 1 Impact of the Position of the Radiator on Energy Consumption and Thermal Comfort in a Mixed Radiant and Convective Heating System Xiangyang Gong David E... the energy consumption and thermal comfort distribution in a typical office with a mixed radiant and convective heating system for two different locations of radiant heat sources. Accurately estimating the energy consumption in a mixed heating space...

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

    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 : XDCnarrowbandheat fluxChinaNews :ProductsAerosolProductsCSSEF

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

    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's PossibleRadiation Protection Radiation ProtectionRaising fundsRealPrintingRecap:

  18. An experimental method for investigating phase transformations in the heat affected zone of welds using synchrotron radiation

    SciTech Connect (OSTI)

    Elmer, J.W.; Wong, J.; Froba, M.; Waide, P.A.; Larson, E.M.

    1995-05-26T23:59:59.000Z

    Although welding is an established technology used in many industrial settings, it is least understand terms of the phases that actually exist, the variation of their spatial disposition with time, and the rate of transformation from one phase to another at various thermal coordinates in the vicinity of the weld. With the availability of high flux and, more recently, high brightness synchrotron x-radiation sources, a number of diffraction and spectroscopic methods have been developed for structural characterization with improved spatial and temporal resolutions to enable in-situ measurements of phases under extreme temperature, pressure and other processing conditions not readily accessible with conventional sources. This paper describes the application of spatially resolved x-ray diffraction (SRXRD) for in-situ investigations of phase transformations in the heat affected zone (HAZ) of fusion welds. Results are presented for gas tungsten (GTA) welds in commercially pure titanium that show the existence of the high temperature bcc {beta}-phase in a 3.3 {plus_minus} 0.3 mm wide HA band adjacent to the liquid weld pool. Phase concentration profiles derived from the SRXRD data further show the co-existence of both the low temperature hcp ({alpha}-phase and the {beta}-phase in the partially, transformed region of the HA. These results represent the first direct observations of solid state phase transformations and mapping of phase boundaries in fusion welds. SRXRD experiments of this type are needed as experimental input for modeling of kinetics of phase transformations and microstructural evolution under the highly non-isothermal conditions produced during welding.

  19. 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.

  20. Transitional regimes of natural convection in a differentially heated cubical cavity under the effects of wall and molecular gas radiation

    SciTech Connect (OSTI)

    Soucasse, L.; Rivière, Ph.; Soufiani, A., E-mail: anouar.soufiani@ecp.fr [CNRS, UPR 288, Laboratoire EM2C, 92290 Châtenay-Malabry (France); École Centrale Paris, 92290 Châtenay-Malabry (France)] [France; Xin, S. [CNRS/INSA-Lyon, UMR 5008, CETHIL, 69621 Villeurbanne (France)] [CNRS/INSA-Lyon, UMR 5008, CETHIL, 69621 Villeurbanne (France); Le Quéré, P. [CNRS, UPR 3251, LIMSI, 91403 Orsay Cedex (France)] [CNRS, UPR 3251, LIMSI, 91403 Orsay Cedex (France)

    2014-02-15T23:59:59.000Z

    The transition to unsteadiness and the dynamics of weakly turbulent natural convection, coupled to wall or gas radiation in a differentially heated cubical cavity with adiabatic lateral walls, are studied numerically. The working fluid is air with small contents of water vapor and carbon dioxide whose infrared spectral radiative properties are modelled by the absorption distribution function model. A pseudo spectral Chebyshev collocation method is used to solve the flow field equations and is coupled to a direct ray tracing method for radiation transport. Flow structures are identified by means of either the proper orthogonal decomposition or the dynamic mode decomposition methods. We first retrieve the classical mechanism of transition to unsteadiness without radiation, characterized by counter-rotating streamwise-oriented vortices generated at the exit of the vertical boundary layers. Wall radiation through a transparent medium leads to a homogenization of lateral wall temperatures and the resulting transition mechanism is similar to that obtained with perfectly conducting lateral walls. The transition is due to an unstable stratification upstream the vertical boundary layers and is characterized by periodically oscillating transverse rolls of axis perpendicular to the main flow. When molecular gas radiation is accounted for, no periodic solution is found and the transition to unsteadiness displays complex structures with chimneys-like rolls whose axes are again parallel to the main flow. The origin of this instability is probably due to centrifugal forces, as suggested previously for the case without radiation. Above the transition to unsteadiness, at Ra = 3 × 10{sup 8}, it is shown that both wall and gas radiation significantly intensify turbulent fluctuations, decrease the thermal stratification in the core of the cavity, and increase the global circulation.

  1. 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.

  2. 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...

  3. 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

  4. THE IMPORTANCE OF PHYSICAL MODELS FOR DERIVING DUST MASSES AND GRAIN SIZE DISTRIBUTIONS IN SUPERNOVA EJECTA. I. RADIATIVELY HEATED DUST IN THE CRAB NEBULA

    SciTech Connect (OSTI)

    Temim, Tea; Dwek, Eli, E-mail: tea.temim@nasa.gov [Observational Cosmology Lab, Code 665, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2013-09-01T23:59:59.000Z

    Recent far-infrared (IR) observations of supernova remnants (SNRs) have revealed significantly large amounts of newly condensed dust in their ejecta, comparable to the total mass of available refractory elements. The dust masses derived from these observations assume that all the grains of a given species radiate at the same temperature, regardless of the dust heating mechanism or grain radius. In this paper, we derive the dust mass in the ejecta of the Crab Nebula, using a physical model for the heating and radiation from the dust. We adopt a power-law distribution of grain sizes and two different dust compositions (silicates and amorphous carbon), and calculate the heating rate of each dust grain by the radiation from the pulsar wind nebula. We find that the grains attain a continuous range of temperatures, depending on their size and composition. The total mass derived from the best-fit models to the observed IR spectrum is 0.019-0.13 M{sub Sun }, depending on the assumed grain composition. We find that the power-law size distribution of dust grains is characterized by a power-law index of 3.5-4.0 and a maximum grain size larger than 0.1 {mu}m. The grain sizes and composition are consistent with what is expected for dust grains formed in a Type IIP supernova (SN). Our derived dust mass is at least a factor of two less than the mass reported in previous studies of the Crab Nebula that assumed more simplified two-temperature models. These models also require a larger mass of refractory elements to be locked up in dust than was likely available in the ejecta. The results of this study show that a physical model resulting in a realistic distribution of dust temperatures can constrain the dust properties and affect the derived dust masses. Our study may also have important implications for deriving grain properties and mass estimates in other SNRs and for the ultimate question of whether SNe are major sources of dust in the Galactic interstellar medium and in external galaxies.

  5. Solar Radiative Heating in First Year Sea Ice M.J. McGuinness 1 , K.A. Landman 2 , H.J. Trodahl 3 , A.E. Pantoja 3

    E-Print Network [OSTI]

    Solar Radiative Heating in First Year Sea Ice M.J. McGuinness 1 , K.A. Landman 2 , H.J. Trodahl 3 ice show daily oscillations consistent with heating by solar radiation. We present and solve a heat for solar power absorption based on Monte Carlo scatter­ ing simulations of penetrating photons. We observe

  6. 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...

  7. An experimental and theoretical study of radiative and conductive heat transfer in nongray semitransparent media

    E-Print Network [OSTI]

    Eryou, N. Dennis

    1969-01-01T23:59:59.000Z

    One dimensional temperature profiles and heat fluxes within a slab of molten glass were measured experimentally. The glass slab was contained in a platinum foil lined ceramic tray inside a high temperature furnace. An ...

  8. The use of high-performance computing to solve participating media radiative heat transfer problems-results of an NSF workshop

    SciTech Connect (OSTI)

    Gritzo, L.A.; Skocypec, R.D. [Sandia National Labs., Albuquerque, NM (United States); Tong, T.W. [Arizona State Univ., Tempe, AZ (United States). Dept. of Mechanical and Aerospace Engineering

    1995-01-11T23:59:59.000Z

    Radiation in participating media is an important transport mechanism in many physical systems. The simulation of complex radiative transfer has not effectively exploited high-performance computing capabilities. In response to this need, a workshop attended by members active in the high-performance computing community, members active in the radiative transfer community, and members from closely related fields was held to identify how high-performance computing can be used effectively to solve the transport equation and advance the state-of-the-art in simulating radiative heat transfer. This workshop was held on March 29-30, 1994 in Albuquerque, New Mexico and was conducted by Sandia National Laboratories. The objectives of this workshop were to provide a vehicle to stimulate interest and new research directions within the two communities to exploit the advantages of high-performance computing for solving complex radiative heat transfer problems that are otherwise intractable.

  9. Genetic Factors Affecting Susceptibility to Low Dose & Low Dose-Rate Radiation

    SciTech Connect (OSTI)

    Bedford, Joel

    2014-04-18T23:59:59.000Z

    Our laboratory has, among other things, developed and used the gamma H2AX focus assay and other chromosomal and cell killing assays to show that differences in this DNA double strand break (dsb) related response can be clearly and distinctly demonstrated for cells which are mildly hyper-radiosensitive such as those associated with A-T heterozygosity. We have found this level of mild hypersensitivity for cells from some 20 to 30 % of apparently normal individuals and from apparently normal parents of Retinoblastoma patients. We found significant differences in gene expression in somatic cells from unaffected parents of Rb patients as compared with normal controls, suggesting that these parents may harbor some as yet unidentified genetic abnormality. In other experiments we sought to determine the extent of differences in normal human cellular reaponses to radiation depending on their irradiation in 2D monolayer vs 3D organized acinar growth conditions. We exmined cell reproductive death, chromosomal aberration induction, and the levels of ?-H2AX foci in cells after single acute gamma-ray doses and immediately after 20 hours of irradiation at a dose rate of 0.0017 Gy/min. We found no significant differences in the dose-responses of these cells under the 2D or 3D growth conditions. While this does not mean such differences cannot occur in other situations, it does mean that they do not generally or necessarily occur. In another series of studies in collaboration with Dr Chuan Li, with supprt from this current grant. We reported a role for apoptotic cell death in promoting wound healing and tissue regeneration in mice. Apoptotic cells released growth signals that stimulated the proliferation of progenitor or stem cells. In yet another collaboration with Dr, B. Chen with funds from this grant, the relative radiosensitivity to cell killing as well as chromosomal instability of 13 DNA-PKcs site-directed mutant cell lines (defective at phosphorylation sites or kinase activity) were examined after exposure of synchronized G1 cells to 137Cs c rays. DNA-PKcs mutant cells defective in phosphorylation at multiple sites withinthe T2609 cluster or within the PI3K domain displayed extreme radiosensitivity. Cells defective at the S2056 cluster or T2609 single site alone were only mildly radiosensitive, but cells defective at even one site in both the S2056 and T2609 clusters were maximally radiosensitive. Thus a synergism between the capacity for phosphorylation at the S2056 and T2609 clusterswas found to be critical for induction of radiosensitivity.

  10. 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

  11. 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

  12. 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.

  13. Optimization of a Mu2e production solenoid heat and radiation shield using MARS15

    SciTech Connect (OSTI)

    Pronskikh, V.S.; Mokhov, N.V.; /Fermilab

    2011-02-01T23:59:59.000Z

    A Monte-Carlo study of several Mu2e Production Solenoid (PS) absorber (heat shield) versions using the MARS15 code has been performed. Optimizations for material as well as cost (amount of tungsten) have been carried out. Studied are such quantities as the number of displacements per atom (DPA) in the helium-cooled solenoid superconducting coils, power density and dynamic heat load in various parts of the PS and its surrounding structures. Prompt dose, residual dose, secondary particle flux are also simulated in the PS structures and the experimental hall. A preliminary choice of the PS absorber design is made on the ground of these studies.

  14. Order Reduction of the Radiative Heat Transfer Model for the Simulation of Plasma Arcs

    E-Print Network [OSTI]

    Fagiano, Lorenzo

    2015-01-01T23:59:59.000Z

    An approach to derive low-complexity models describing thermal radiation for the sake of simulating the behavior of electric arcs in switchgear systems is presented. The idea is to approximate the (high dimensional) full-order equations, modeling the propagation of the radiated intensity in space, with a model of much lower dimension, whose parameters are identified by means of nonlinear system identification techniques. The low-order model preserves the main structural aspects of the full-order one, and its parameters can be straightforwardly used in arc simulation tools based on computational fluid dynamics. In particular, the model parameters can be used together with the common approaches to resolve radiation in magnetohydrodynamic simulations, including the discrete-ordinate method, the P-N methods and photohydrodynamics. The proposed order reduction approach is able to systematically compute the partitioning of the electromagnetic spectrum in frequency bands, and the related absorption coefficients, tha...

  15. L- and M-shell absorption measurements of radiatively heated Fe plasma

    SciTech Connect (OSTI)

    Zhang Jiyan; Li Hang; Zhao Yang; Xiong Gang; Yuan Zheng; Zhang Haiying; Yang Guohong; Yang Jiamin; Liu Shenye; Jiang Shaoen; Ding Yongkun; Zhang Baohan; Zheng Zhijian [Research Center of Laser Fusion, P. O. Box 919-986, Mianyang 621900 (China); Xu Yan; Meng Xujun; Yan Jun [Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China)

    2012-11-15T23:59:59.000Z

    Measurements of iron-plasma absorption spectrum over 150-1200 eV photon energy range were reported at temperature T = (72 {+-} 4) eV. The electron temperature was diagnosed with the absorption spectrum of aluminum mixed with iron. The density was not diagnosed directly but obtained from a radiative hydrodynamic simulation with the Multi-1D code. The broad photon energy range enables simultaneous observation of the L-shell and M-shell transitions that dominate the radiation transport at this temperature. The spectrally resolved transmission data were compared to the detailed-configuration-accounting model calculations and reasonable agreement was found.

  16. 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.

  17. Numerical simulation of three-dimensional combined convective radiative heat transfer in rectangular channels

    E-Print Network [OSTI]

    Ko, Min Seok

    2009-05-15T23:59:59.000Z

    ? =0.1, 0.2, and 0.4) and scattering albedo ( ?=0, 0.25, 0.5, 0.75 and 1). Variation of thermophysical properties with temperature was considered in this study. In this work consideration was given only to cooling. Effects of those radiative...

  18. 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

  19. Atmospheric State, Cloud Microphysics and Radiative Flux

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

    Mace, Gerald

    Atmospheric thermodynamics, cloud properties, radiative fluxes and radiative heating rates for the ARM Southern Great Plains (SGP) site. The data represent a characterization of the physical state of the atmospheric column compiled on a five-minute temporal and 90m vertical grid. Sources for this information include raw measurements, cloud property and radiative retrievals, retrievals and derived variables from other third-party sources, and radiative calculations using the derived quantities.

  20. Evaluation of Reaction Rate Theory and Monte Carlo Methods for Application to Radiation-Induced Microstructural Characterization

    SciTech Connect (OSTI)

    Stoller, Roger E [ORNL; Golubov, Stanislav I [ORNL; Becquart, C. S. [Universite de Lille; Domain, C. [EDF R& D, Clamart, France

    2007-08-01T23:59:59.000Z

    The multiscale modeling scheme encompasses models from the atomistic to the continuum scale. Phenomena at the mesoscale are typically simulated using reaction rate theory, Monte Carlo, or phase field models. These mesoscale models are appropriate for application to problems that involve intermediate length scales, and timescales from those characteristic of diffusion to long-term microstructural evolution (~?s to years). Although the rate theory and Monte Carlo models can be used simulate the same phenomena, some of the details are handled quite differently in the two approaches. Models employing the rate theory have been extensively used to describe radiation-induced phenomena such as void swelling and irradiation creep. The primary approximations in such models are time- and spatial averaging of the radiation damage source term, and spatial averaging of the microstructure into an effective medium. Kinetic Monte Carlo models can account for these spatial and temporal correlations; their primary limitation is the computational burden which is related to the size of the simulation cell. A direct comparison of RT and object kinetic MC simulations has been made in the domain of point defect cluster dynamics modeling, which is relevant to the evolution (both nucleation and growth) of radiation-induced defect structures. The primary limitations of the OKMC model are related to computational issues. Even with modern computers, the maximum simulation cell size and the maximum dose (typically much less than 1 dpa) that can be simulated are limited. In contrast, even very detailed RT models can simulate microstructural evolution for doses up 100 dpa or greater in clock times that are relatively short. Within the context of the effective medium, essentially any defect density can be simulated. Overall, the agreement between the two methods is best for irradiation conditions which produce a high density of defects (lower temperature and higher displacement rate), and for materials that have a relatively high density of fixed sinks such as dislocations.

  1. Remote sensing of tropical tropopause layer radiation balance using A-train measurements

    E-Print Network [OSTI]

    Liou, K. N.

    the relevant horizontal and vertical information for assessing TTL solar heating and infrared cooling rates; accepted 8 August 2008; published 12 November 2008. [1] Determining the level of zero net radiative heating the distribution of cloud properties relevant to heating rate analysis. The ability of CloudSat measurements

  2. Heat blanketing envelopes and thermal radiation of strongly magnetized neutron stars

    E-Print Network [OSTI]

    A. Y. Potekhin; G. Chabrier; D. G. Yakovlev

    2007-09-04T23:59:59.000Z

    Strong (B >> 10^9 G) and superstrong (B > 10^{14} G) magnetic fields profoundly affect many thermodynamic and kinetic characteristics of dense plasmas in neutron star envelopes. In particular, they produce strongly anisotropic thermal conductivity in the neutron star crust and modify the equation of state and radiative opacities in the atmosphere, which are major ingredients of the cooling theory and spectral atmosphere models. As a result, both the radiation spectrum and the thermal luminosity of a neutron star can be affected by the magnetic field. We briefly review these effects and demonstrate the influence of magnetic field strength on the thermal structure of an isolated neutron star, putting emphasis on the differences brought about by the superstrong fields and high temperatures of magnetars. For the latter objects, it is important to take proper account of a combined effect of the magnetic field on thermal conduction and neutrino emission at densities \\rho > 10^{10} g cm^{-3}. We show that the neutrino emission puts a B-dependent upper limit on the effective surface temperature of a cooling neutron star.

  3. Inclined monochromator for high heat-load synchrotron x-ray radiation

    DOE Patents [OSTI]

    Khounsary, A.M.

    1994-02-15T23:59:59.000Z

    A double crystal monochromator is described including two identical, parallel crystals, each of which is cut such that the normal to the diffraction planes of interest makes an angle less than 90 degrees with the surface normal. Diffraction is symmetric, regardless of whether the crystals are symmetrically or asymmetrically cut, enabling operation of the monochromator with a fixed plane of diffraction. As a result of the inclination of the crystal surface, an incident beam has a footprint area which is elongated both vertically and horizontally when compared to that of the conventional monochromator, reducing the heat flux of the incident beam and enabling more efficient surface cooling. Because after inclination of the crystal only a fraction of thermal distortion lies in the diffraction plane, slope errors and the resultant misorientation of the diffracted beam are reduced. 11 figures.

  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. Video-rate optical dosimetry and dynamic visualization of IMRT and VMAT treatment plans in water using Cherenkov radiation

    SciTech Connect (OSTI)

    Glaser, Adam K., E-mail: Adam.K.Glaser@dartmouth.edu, E-mail: Brian.W.Pogue@dartmouth.edu; Andreozzi, Jacqueline M.; Davis, Scott C. [Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755 (United States)] [Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755 (United States); Zhang, Rongxiao [Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755 (United States)] [Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755 (United States); Pogue, Brian W., E-mail: Adam.K.Glaser@dartmouth.edu, E-mail: Brian.W.Pogue@dartmouth.edu [Department of Physics and Astronomy and Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755 (United States); Fox, Colleen J.; Gladstone, David J. [Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire 03766 (United States)] [Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire 03766 (United States)

    2014-06-15T23:59:59.000Z

    Purpose: A novel technique for optical dosimetry of dynamic intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) plans was investigated for the first time by capturing images of the induced Cherenkov radiation in water. Methods: A high-sensitivity, intensified CCD camera (ICCD) was configured to acquire a two-dimensional (2D) projection image of the Cherenkov radiation induced by IMRT and VMAT plans, based on the Task Group 119 (TG-119) C-Shape geometry. Plans were generated using the Varian Eclipse treatment planning system (TPS) and delivered using 6 MV x-rays from a Varian TrueBeam Linear Accelerator (Linac) incident on a water tank doped with the fluorophore quinine sulfate. The ICCD acquisition was gated to the Linac target trigger pulse to reduce background light artifacts, read out for a single radiation pulse, and binned to a resolution of 512 × 512 pixels. The resulting videos were analyzed temporally for various regions of interest (ROI) covering the planning target volume (PTV) and organ at risk (OAR), and summed to obtain an overall light intensity distribution, which was compared to the expected dose distribution from the TPS using a gamma-index analysis. Results: The chosen camera settings resulted in 23.5 frames per second dosimetry videos. Temporal intensity plots of the PTV and OAR ROIs confirmed the preferential delivery of dose to the PTV versus the OAR, and the gamma analysis yielded 95.9% and 96.2% agreement between the experimentally captured Cherenkov light distribution and expected TPS dose distribution based upon a 3%/3 mm dose difference and distance-to-agreement criterion for the IMRT and VMAT plans, respectively. Conclusions: The results from this initial study demonstrate the first documented use of Cherenkov radiation for video-rate optical dosimetry of dynamic IMRT and VMAT treatment plans. The proposed modality has several potential advantages over alternative methods including the real-time nature of the acquisition, and upon future refinement may prove to be a robust and novel dosimetry method with both research and clinical applications.

  6. Experimental and Simulation of Gamma Radiation Dose Rate for High Exposure Building Material

    E-Print Network [OSTI]

    Abbasi, Akbar

    2015-01-01T23:59:59.000Z

    Natural radioactivity concentrations in high exposure building materials are commonly used in Iran, which is measured a direct exposure by using {\\gamma}-ray spectrometry. The values for 226Ra, 232Th and 40K were in the ranges 3.8 - 94.2, 6.5 - 172.2 and 556.9 - 1539.2 Bqkg-1, respectively. The absorbed dose rates in the standard dwelling room due to 238U, 232Th series and 40K were calculated with MCNPX code. The simulation and experimental results were between 7.95 - 41.74 and 8.36 - 39.99 nGy h-1, respectively. These results were compared with experimental outing and there was overlap closely. The simulation results are able to develop for any kind of dwelling places.

  7. Experimental and Simulation of Gamma Radiation Dose Rate for High Exposure Building Material

    E-Print Network [OSTI]

    Akbar Abbasi; Mustfa Hassanzadeh

    2014-10-27T23:59:59.000Z

    Natural radioactivity concentrations in high exposure building materials are commonly used in Iran, which is measured a direct exposure by using {\\gamma}-ray spectrometry. The values for 226Ra, 232Th and 40K were in the ranges 3.8 - 94.2, 6.5 - 172.2 and 556.9 - 1539.2 Bqkg-1, respectively. The absorbed dose rates in the standard dwelling room due to 238U, 232Th series and 40K were calculated with MCNPX code. The simulation and experimental results were between 7.95 - 41.74 and 8.36 - 39.99 nGy h-1, respectively. These results were compared with experimental outing and there was overlap closely. The simulation results are able to develop for any kind of dwelling places.

  8. Effects of thermal radiation heat transfer on flame acceleration and transition to detonation in dust cloud flames: Origins of dust explosion

    E-Print Network [OSTI]

    Ivanov, Michael A Liberman M F

    2015-01-01T23:59:59.000Z

    We examines regimes of the hydrogen flames propagation and ignition of mixtures heated by the radiation emitted from the flame. The gaseous phase is assumed to be transparent for radiation, while the suspended particles of the dust cloud ahead of the flame absorb and reemit the radiation. The radiant heat absorbed by the particles is then lost by conduction to the surrounding unreacted gaseous phase so that the gas phase temperature lags that of the particles. The direct numerical simulations solve the full system of two phase gas dynamic time-dependent equations with a detailed chemical kinetics for a plane flames propagating through a dust cloud. Depending on the spatial distribution of the dispersed particles and on the value of radiation absorption length the consequence of the radiative preheating of the unreacted mixture can be either the increase of the flame velocity for uniformly dispersed particles or ignition deflagration or detonation ahead of the flame via the Zel'dovich gradient mechanism in the...

  9. Spherical collapse with heat flow and without horizon

    E-Print Network [OSTI]

    A. Banerjee; S. Chatterjee; N. Dadhich

    2002-09-10T23:59:59.000Z

    We present a class of solutions for a heat conducting fluid sphere, which radiates energy during collapse without the appearance of horizon at the boundary at any stage of the collapse. A simple model shows that there is no accumulation of energy due to collapse since it radiates out at the same rate as it is being generated.

  10. Ionizing Radiation in Smoothed Particle Hydrodynamics

    E-Print Network [OSTI]

    O. Kessel-Deynet; A. Burkert

    2000-02-11T23:59:59.000Z

    A new method for the inclusion of ionizing radiation from uniform radiation fields into 3D Smoothed Particle Hydrodynamics (SPHI) simulations is presented. We calculate the optical depth for the Lyman continuum radiation from the source towards the SPHI particles by ray-tracing integration. The time-dependent ionization rate equation is then solved locally for the particles within the ionizing radiation field. Using test calculations, we explore the numerical behaviour of the code with respect to the implementation of the time-dependent ionization rate equation. We also test the coupling of the heating caused by the ionization to the hydrodynamical part of the SPHI code.

  11. Electronic dose conversion technique using a NaI(Tl) detector for assessment of exposure dose rate from environmental radiation

    SciTech Connect (OSTI)

    Cho, G.; Kim, H.K. [Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of)] [Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of); Woo, H.; Oh, G. [Korea Electric Power Research Inst., Taejon (Korea, Republic of)] [Korea Electric Power Research Inst., Taejon (Korea, Republic of); Ha, D.K. [Samchang Enterprise Co., Anyang (Korea, Republic of)] [Samchang Enterprise Co., Anyang (Korea, Republic of)

    1998-06-01T23:59:59.000Z

    An electronic dose conversion technique to assess the exposure dose rate due to environmental radiation especially from terrestrial sources was developed. For a 2 x 2 inch cylindrical NaI(Tl) scintillation detector, pulse-height spectra were obtained for gamma-rays of energy up to 3 MeV by Monte Carlo simulation. Based on the simulation results and the experimentally fitted energy resolution, dose conversion factors were calculated by a numerical decomposition method. These calculated dose conversion factors were, then, electronically implemented to a developed dose conversion unit (DCU) which is a microprocessor-controlled single channel analyzer (SCA) with variable discrimination levels. The simulated spectra were confirmed by measurement of several monoenergetic gamma spectra with a multichannel analyzer (MCA). The converted exposure dose rates from the implemented dose conversion algorithm in the DCU were also evaluated for a field test in the vicinity of the nuclear power plant at Kori as well as for several standard sources, and the results were in good agreement with separate measurement by a high pressure ionization chamber (HPIC) within a 6.4% deviation.

  12. 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

  13. HEAT AND MOISTURE TRANSFER THROUGH CLOTHING

    E-Print Network [OSTI]

    Voelker, Conrad; Hoffmann, Sabine; Kornadt, Oliver; Arens, Edward; Zhang, Hui; Huizenga, Charlie

    2009-01-01T23:59:59.000Z

    R. C. Eberhart (ed), Heat transfer in medicine and biology.between convective heat transfer and mass transferConvective and radiative heat transfer coefficients for

  14. Heat and moisture transfer through clothing

    E-Print Network [OSTI]

    Voelker, Conrad; Hoffmann, Sabine; Kornadt, Oliver; Arens, Edward; Zhang, Hui; Huizenga, Charlie

    2009-01-01T23:59:59.000Z

    R. C. Eberhart (ed), Heat transfer in medicine and biology.Convective and radiative heat transfer coefficients forbetween convective heat transfer and mass transfer

  15. Investigating the Radiative Impact Clouds Using Retrieved Properties to Classify Cloud Type

    E-Print Network [OSTI]

    Hogan, Robin

    of Reading, RG6 6AL, UK Abstract. Active remote sensing allows cloud properties such as ice and liquid water remote sensing, Cloud categorization, Cloud properties, Radiative impact. PACS: 92.60. Vb. INTRODUCTION in a radiation scheme which can simulate the radiation budget and heating rates throughout the atmospheric

  16. 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

  17. Conservation laws, radiative decay rates, and excited state localization in organometallic complexes with strong spin-orbit coupling

    E-Print Network [OSTI]

    B. J. Powell

    2015-01-05T23:59:59.000Z

    There is longstanding fundamental interest in 6-fold coordinated $d^6$ ($t_{2g}^6$) transition metal complexes such as [Ru(bpy)$_3$]$^{2+}$ and Ir(ppy)$_3$, particularly their phosphorescence. This interest has increased with the growing realisation that many of these complexes have potential uses in applications including photovoltaics, imaging, sensing, and light-emitting diodes. In order to design new complexes with properties tailored for specific applications a detailed understanding of the low-energy excited states, particularly the lowest energy triplet state, $T_1$, is required. Here we describe a model of pseudo-octahedral complexes based on a pseudo-angular momentum representation and show that the predictions of this model are in excellent agreement with experiment - even when the deviations from octahedral symmetry are large. This model gives a natural explanation of zero-field splitting of $T_1$ and of the relative radiative rates of the three sublevels in terms of the conservation of time-reversal parity and total angular momentum modulo two. We show that the broad parameter regime consistent with the experimental data implies significant localization of the excited state.

  18. Conservation laws, radiative decay rates, and excited state localization in organometallic complexes with strong spin-orbit coupling

    E-Print Network [OSTI]

    Powell, B J

    2015-01-01T23:59:59.000Z

    There is longstanding fundamental interest in 6-fold coordinated $d^6$ ($t_{2g}^6$) transition metal complexes such as [Ru(bpy)$_3$]$^{2+}$ and Ir(ppy)$_3$, particularly their phosphorescence. This interest has increased with the growing realisation that many of these complexes have potential uses in applications including photovoltaics, imaging, sensing, and light-emitting diodes. In order to design new complexes with properties tailored for specific applications a detailed understanding of the low-energy excited states, particularly the lowest energy triplet state, $T_1$, is required. Here we describe a model of pseudo-octahedral complexes based on a pseudo-angular momentum representation and show that the predictions of this model are in excellent agreement with experiment - even when the deviations from octahedral symmetry are large. This model gives a natural explanation of zero-field splitting of $T_1$ and of the relative radiative rates of the three sublevels in terms of the conservation of time-revers...

  19. Development of a Heat Transfer Model for the Integrated Facade Heating

    E-Print Network [OSTI]

    Gong, X.; Archer, D. H.; Claridge, D. E.

    2007-01-01T23:59:59.000Z

    the heat transfer process of facade heating (mullion radiators) in a pilot research project in Pittsburgh, PA. The heat transfer model for facade heating is developed and verified by measured data. The comparison shows that the heat transfer model predicts...

  20. Development of a Heat Transfer Model for the Integrated Facade Heating 

    E-Print Network [OSTI]

    Gong, X.; Archer, D. H.; Claridge, D. E.

    2007-01-01T23:59:59.000Z

    the heat transfer process of facade heating (mullion radiators) in a pilot research project in Pittsburgh, PA. The heat transfer model for facade heating is developed and verified by measured data. The comparison shows that the heat transfer model predicts...

  1. 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.

  2. 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.

  3. 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

  4. 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.

  5. American Society for Radiation Oncology (ASTRO) and American College of Radiology (ACR) Practice Guideline for the Performance of High-Dose-Rate Brachytherapy

    SciTech Connect (OSTI)

    Erickson, Beth A. [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Demanes, D. Jeffrey [Department of Radiation Oncology , University of California, Los Angeles, CA (United States); Ibbott, Geoffrey S. [Radiological Physics Center, MD Anderson Cancer Center, Houston, TX (United States); Hayes, John K. [Gamma West Brachytherapy, Salt Lake City, UT (United States); Hsu, I-Chow J. [Department of Radiation Oncology, University of California San Francisco, San Francisco, CA (United States); Morris, David E. [Department of Radiation Oncology, University of North Carolina, Chapel Hill, NC (United States); Rabinovitch, Rachel A. [Department of Radiation Oncology, University of Colorado Denver, Aurora, CO (United States); Tward, Jonathan D. [Department of Radiation Oncology, Huntsman Cancer Institute, Salt Lake City, UT (United States); Rosenthal, Seth A. [Radiation Oncology Centers, Radiological Associates of Sacramento, Sacramento, CA (United States)

    2011-03-01T23:59:59.000Z

    High-Dose-Rate (HDR) brachytherapy is a safe and efficacious treatment option for patients with a variety of different malignancies. Careful adherence to established standards has been shown to improve the likelihood of procedural success and reduce the incidence of treatment-related morbidity. A collaborative effort of the American College of Radiology (ACR) and American Society for Therapeutic Radiation Oncology (ASTRO) has produced a practice guideline for HDR brachytherapy. The guideline defines the qualifications and responsibilities of all the involved personnel, including the radiation oncologist, physicist and dosimetrists. Review of the leading indications for HDR brachytherapy in the management of gynecologic, thoracic, gastrointestinal, breast, urologic, head and neck, and soft tissue tumors is presented. Logistics with respect to the brachytherapy implant procedures and attention to radiation safety procedures and documentation are presented. Adherence to these practice guidelines can be part of ensuring quality and safety in a successful HDR brachytherapy program.

  6. Electron loss rates from the outer radiation belt caused by the filling of the outer plasmasphere: the calm before the storm

    SciTech Connect (OSTI)

    Borovsky, Joseph E [Los Alamos National Laboratory; Denton, Michael H [LANCASTER UNIV

    2009-01-01T23:59:59.000Z

    Measurements from 7 spacecraft in geosynchronous orbit are analyzed to determine the decay rate of the number density of the outer electron radiation belt prior to the onset of high-speed-stream-driven geomagnetic storms. Superposed-data analysis is used wan(?) a collection of 124 storms. When there is a calm before the storm, the electron number density decays exponentially before the storm with a 3.4-day e-folding time: beginning about 4 days before storm onset, the density decreases from {approx}4x10{sup -4} cm{sup -3} to {approx}1X 10{sup -4} cm{sup -3}. When there is not a calm before the storm, the number-density decay is very smalL The decay in the number density of radiation-belt electrons is believed to be caused by pitch-angle scattering of electrons into the atmospheric loss cone as the outer plasmasphere fills during the calms. While the radiation-belt electron density decreases, the temperature of the electron radiation belt holds approximately constant, indicating that the electron precipitation occurs equally at all energies. Along with the number density decay, the pressure of the outer electron radiation belt decays and the specific entropy increases. From the measured decay rates, the electron flux to the atmosphere is calculated and that flux is 3 orders of magnitude less than thermal fluxes in the magnetosphere, indicating that the radiation-belt pitch-angle scattering is 3 orders weaker than strong diffusion. Energy fluxes into the atmosphere are calculated and found to be insufficient to produce visible airglow.

  7. 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

  8. Sexual Functioning Among Endometrial Cancer Patients Treated With Adjuvant High-Dose-Rate Intra-Vaginal Radiation Therapy

    SciTech Connect (OSTI)

    Damast, Shari, E-mail: shari.damast@yale.edu [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Alektiar, Kaled M. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Goldfarb, Shari [Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Eaton, Anne; Patil, Sujata [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Mosenkis, Jeffrey [Department of Comparative Human Development, University of Chicago, Chicago, Illinois (United States)] [Department of Comparative Human Development, University of Chicago, Chicago, Illinois (United States); Bennett, Antonia [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Atkinson, Thomas [Department of Psychiatry, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Psychiatry, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Jewell, Elizabeth; Leitao, Mario; Barakat, Richard; Carter, Jeanne [Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Basch, Ethan [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

    2012-10-01T23:59:59.000Z

    Purpose: We used the Female Sexual Function Index (FSFI) to investigate the prevalence of sexual dysfunction (SD) and factors associated with diminished sexual functioning in early stage endometrial cancer (EC) patients treated with simple hysterectomy and adjuvant brachytherapy. Methods and Materials: A cohort of 104 patients followed in a radiation oncology clinic completed questionnaires to quantify current levels of sexual functioning. The time interval between hysterectomy and questionnaire completion ranged from <6 months to >5 years. Multivariate regression was performed using the FSFI as a continuous variable (score range, 1.2-35.4). SD was defined as an FSFI score of <26, based on the published validation study. Results: SD was reported by 81% of respondents. The mean ({+-} standard deviation) domain scores in order of highest-to-lowest functioning were: satisfaction, 2.9 ({+-}2.0); orgasm, 2.5 ({+-}2.4); desire, 2.4 ({+-}1.3); arousal, 2.2 ({+-}2.0); dryness, 2.1 ({+-}2.1); and pain, 1.9 ({+-}2.3). Compared to the index population in which the FSFI cut-score was validated (healthy women ages 18-74), all scores were low. Compared to published scores of a postmenopausal population, scores were not statistically different. Multivariate analysis isolated factors associated with lower FSFI scores, including having laparotomy as opposed to minimally invasive surgery (effect size, -7.1 points; 95% CI, -11.2 to -3.1; P<.001), lack of vaginal lubricant use (effect size, -4.4 points; 95% CI, -8.7 to -0.2, P=.040), and short time interval (<6 months) from hysterectomy to questionnaire completion (effect size, -4.6 points; 95% CI, -9.3-0.2; P=.059). Conclusions: The rate of SD, as defined by an FSFI score <26, was prevalent. The postmenopausal status of EC patients alone is a known risk factor for SD. Additional factors associated with poor sexual functioning following treatment for EC included receipt of laparotomy and lack of vaginal lubricant use.

  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. Impact of subgrid-scale radiative heating variability on the stratocumulus-to-trade cumulus transition in climate models

    SciTech Connect (OSTI)

    Xiao, Heng; Gustafson, William I.; Wang, Hailong

    2014-04-29T23:59:59.000Z

    Subgrid-scale interactions between turbulence and radiation are potentially important for accurately reproducing marine low clouds in climate models. To better understand the impact of these interactions, the Weather Research and Forecasting (WRF) model is configured for large eddy simulation (LES) to study the stratocumulus-to-trade cumulus (Sc-to-Cu) transition. Using the GEWEX Atmospheric System Studies (GASS) composite Lagrangian transition case and the Atlantic Trade Wind Experiment (ATEX) case, it is shown that the lack of subgrid-scale turbulence-radiation interaction, as is the case in current generation climate models, accelerates the Sc-to-Cu transition. Our analysis suggests that in cloud-topped boundary layers subgrid-scale turbulence-radiation interactions contribute to stronger production of temperature variance, which in turn leads to stronger buoyancy production of turbulent kinetic energy and helps to maintain the Sc cover.

  11. The 3D thermal analysis is performed for the radiation heat load at all stages of the HRS op-

    E-Print Network [OSTI]

    McDonald, Kirk

    . The coil layers were separated from each other by two layers of insulation with a layer of Al in between and cost. The beam dump was designed to both accu- mulate the spent beam and keep its temperature and air dynamic heat loads to the cryogenic system, a reason- able lifetime of the coil components, acceptable -on

  12. 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.

  13. Low dose radiation hypersensitivity and clustered DNA damages in human fibroblasts exposed to low dose and dose rate protons or 137CS y-rays

    SciTech Connect (OSTI)

    Bennett P. V.; Bennett, P.V.; Keszenman, D.J.; Johnson, A.M.; Sutherland, B.M.; Wilson, P.F.

    2013-05-14T23:59:59.000Z

    Effective radioprotection for human space travelers hinges upon understanding the individual properties of charged particles. A significant fraction of particle radiation astronauts will encounter in space exploratory missions will come from high energy protons in galactic cosmic radiation (GCR) and/or possible exposures to lower energy proton flux from solar particle events (SPEs). These potential exposures present major concerns for NASA and others, in planning and executing long term space exploratory missions. We recently reported cell survival and transformation (acquisition of anchorage-independent growth in soft agar) frequencies in apparently normal NFF-28 primary human fibroblasts exposed to 0-30 cGy of 50MeV, 100MeV (SPE-like), or 1000 MeV (GCR-like) monoenergetic protons. These were modeled after 1989 SPE energies at an SPE-like low dose-rate (LDR) of 1.65 cGy/min or high dose rate (HDR) of 33.3 cGy/min delivered at the NASA Space Radiation Laboratory (NSRL) at BNL.

  14. 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

  15. Energy levels and radiative rates for transitions in B-like to F-like Kr ions (Kr XXXII-XXVIII)

    SciTech Connect (OSTI)

    Aggarwal, K.M. [Astrophysics Research Centre, School of Mathematics and Physics, Queen's University, Belfast BT7 1NN, Northern Ireland (United Kingdom)], E-mail: K.Aggarwal@qub.ac.uk; Keenan, F.P. [Astrophysics Research Centre, School of Mathematics and Physics, Queen's University, Belfast BT7 1NN, Northern Ireland (United Kingdom); Lawson, K.D. [EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom)

    2008-05-15T23:59:59.000Z

    Energy levels, radiative rates, oscillator strengths, line strengths, and lifetimes have been calculated for transitions in B-like to F-like Kr ions, Kr XXXIII-XXVIII. For the calculations, the fully relativistic GRASP code has been adopted, and results are reported for all electric dipole (E1), electric quadrupole (E2), magnetic dipole (M1), and magnetic quadrupole (M2) transitions among the lowest 125, 236, 272, 226, and 113 levels of Kr XXXII, Kr XXXI, Kr XXX, Kr XXIX, and Kr XXVIII, respectively, belonging to the n {<=} 3 configurations. Comparisons are made with earlier available theoretical and experimental results, and some discrepancies have been noted and explained.

  16. The effect of non-uniform radiative damping on the zonal-mean dynamics of

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    to an imposed forcing or diabatic heating is examined in a zonal-mean model of the middle atmosphere. Attention radiative damping rates are more sensitive in terms of temperature to the remote in uence of the diabatic is the strongly relaxational nature of diabatic heating. It is this feature, for example, which leads to the zonal

  17. The convergence of an explicit finite difference solution for transient heat transfer in solids with radiation at one boundary

    E-Print Network [OSTI]

    Patel, Bhagubhai Desaibhai

    1966-01-01T23:59:59.000Z

    ? FOR RADIATION NUMBER N + o 5 o MODULUS M = 4? USUAL PROCEDURE ~ S I NK' NTHI TA NODE I NO DE 2 NODE3 NODE4 NODE5 NODE6 0 ' oo0o n, 0100 0 ' 0200 n ~ c'300 0 ' 0400 0 ~ 0500 O, oeoo 0 ' 0700 Oe0800 0 ' 0900 Oe1000 n ~ 1100 Oe1200 Oo1300 0... of this method can be I'ound in the graphical method commonly known as the Schmidt method, but, Binder first developed it independently. During the peri, od in which these meth+de were developed the temperatures normally worked with were 'relatively lower...

  18. Cavity-enhanced radiative emission rate in a single-photon-emitting diode operating at 0.5 GHz

    E-Print Network [OSTI]

    David J. P. Ellis; Anthony J. Bennett; Samuel J. Dewhurst; Christine A. Nicoll; David A. Ritchie; Andrew J. Shields

    2008-04-04T23:59:59.000Z

    We report the observation of a Purcell enhancement in the electroluminescence decay rate of a single quantum dot, embedded in a microcavity light-emitting-diode structure. Lateral confinement of the optical mode was achieved using an annulus of low-refractive-index aluminium oxide, formed by wet oxidation. The same layer acts as a current aperture, reducing the active area of the device without impeding the electrical properties of the p-i-n diode. This allowed single photon electroluminescence to be demonstrated at repetition rates up to 0.5 GHz.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. Energy levels, oscillator strengths, and radiative rates for Si-like Zn XVII, Ga XVIII, Ge XIX, and As XX

    SciTech Connect (OSTI)

    Abou El-Maaref, A., E-mail: aahmh@hotmail.com [Physics Department, Faculty of Science, Al-Azhar University, Assuit (Egypt); Allam, S.H.; El-Sherbini, Th.M. [Laboratory of Lasers and New Materials, Physics Department, Faculty of Science, Cairo University, Giza (Egypt)] [Laboratory of Lasers and New Materials, Physics Department, Faculty of Science, Cairo University, Giza (Egypt)

    2014-01-15T23:59:59.000Z

    The energy levels, oscillator strengths, line strengths, and transition probabilities for transitions among the terms belonging to the 3s{sup 2}3p{sup 2}, 3s3p{sup 3}, 3s{sup 2}3p3d, 3s{sup 2}3p4s, 3s{sup 2}3p4p and 3s{sup 2}3p4d configurations of silicon-like ions (Zn XVII, Ga XVIII, Ge XIX, and As XX) have been calculated using the configuration-interaction code CIV3. The calculations have been carried out in the intermediate coupling scheme using the Breit–Pauli Hamiltonian. The present calculations have been compared with the available experimental data and other theoretical calculations. Most of our calculations of energy levels and oscillator strengths (in length form) show good agreement with both experimental and theoretical data. Lifetimes of the excited levels have also been calculated. -- Highlights: •We have calculated the fine-structure energy levels of Si-like Zn, Ga, Ge and As. •The calculations are performed using the configuration interaction method (CIV3). •We have calculated the oscillator strengths, line strengths and transition rates. •The wavelengths of the transitions are listed in this article. •We also have made comparisons between our data and other calculations.

  4. Rotating bubble membrane radiator

    DOE Patents [OSTI]

    Webb, Brent J. (West Richland, WA); Coomes, Edmund P. (West Richland, WA)

    1988-12-06T23:59:59.000Z

    A heat radiator useful for expelling waste heat from a power generating system aboard a space vehicle is disclosed. Liquid to be cooled is passed to the interior of a rotating bubble membrane radiator, where it is sprayed into the interior of the bubble. Liquid impacting upon the interior surface of the bubble is cooled and the heat radiated from the outer surface of the membrane. Cooled liquid is collected by the action of centrifical force about the equator of the rotating membrane and returned to the power system. Details regarding a complete space power system employing the radiator are given.

  5. Effects of p60 sCo gamma radiation on Sarcina lutea: A comparison of effects at two different exposure rates and a study of the radiosensitizing properties of prodigiosin.

    E-Print Network [OSTI]

    Blair, George Washington

    1973-01-01T23:59:59.000Z

    of pigmented and nonpigmented cells. Radiation Res. 48, 40-52 (1971). 8. R. P. Williams, Biosynthesis of Prodigiosin, a Secondary Metabolite of Serratia marcescens, ~A 1. Microbiol. 25, 396-402 (1973). 9. M. M. Matthews, and N. I. Krinsky, The relatioship... Radiation on Sarcina ]utes: A Comparison of Effects at Two Different Exposure Rates and A Study of the Radiosensitizing Properties of. Prodigiosin (August 1973) George W. Blair, Jr. , B. S, , University of Chattanooga Directed by: Dr. R. D. Neff...

  6. 1. Quart. Spectrosc. Radial. Trom~r. Vol. 11,pp.144-1462. Pqamon Press 1971. Printed in Great Britain NON-GREY RADIATIVE HEAT TRANSFER

    E-Print Network [OSTI]

    Siewert, Charles E.

    -grey heat transfer model is that of SIMMONS and FERZIGER(~)who used the normal modes(4) of the equation

  7. Developing Low-Conductance Window Frames: Capabilities and Limitations of Current Window Heat Transfer Design Tools

    E-Print Network [OSTI]

    Gustavsen, Arild

    2009-01-01T23:59:59.000Z

    free convection. In: Heat Transfer and Turbulent Buoyantof convection heat transfer and develop correlations.and radiation heat transfer and develop correlations for

  8. 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.

  9. 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 ...

  10. 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.

  11. Energy levels, oscillator strengths, radiative decay rates, and fine-structure collision strengths for the Zn-like ions Nb XII and Mo XIII

    SciTech Connect (OSTI)

    Liang, Liang, E-mail: liangll501@163.com; Liu, Xu-yang; Zhou, Chao

    2014-07-15T23:59:59.000Z

    Energy levels, line strengths, oscillator strengths, radiative decay rates, and fine-structure collision strengths are presented for the Zn-like ions Nb XII and Mo XIII. The atomic data are calculated with the AUTOSTRUCTURE code, where relativistic corrections are introduced according to the Breit–Pauli distorted wave approach. We present the calculations of atomic data for 110 fine-structure levels generated from fifteen configurations (1s{sup 2}2s{sup 2}2p{sup 6}3s{sup 2}3p{sup 6}3d{sup 10})4s{sup 2}, 4s4p, 4p{sup 2}, 4s4d, 4s4f, 4s5s, 4p4d, 4s5p, 4s5d, 4p4f, 4p5s, 4d{sup 2}, 4d4f, 4f{sup 2}, and 3d{sup 9}4s{sup 2}4p. Fine-structure collision strengths for transitions from the ground and the first four excited levels are presented at six electron energies (20, 50, 80, 110, 150, and 180 Ryd). Our atomic structure data are compared with the available experimental and theoretical results.

  12. Relative Biologic Effects of Low-Dose-Rate {alpha}-Emitting {sup 227}Th-Rituximab and {beta}-Emitting {sup 90}Y-Tiuexetan-Ibritumomab Versus External Beam X-Radiation

    SciTech Connect (OSTI)

    Dahle, Jostein [Department of Radiation Biology, Norwegian Radium Hospital, Montebello, Oslo (Norway)], E-mail: jostein.dahle@rr-research.no; Bruland, Oyvind S. [University of Oslo and Department of Oncology, Norwegian Radium Hospital, Montebello, Oslo (Norway); Larsen, Roy H. [Department of Radiation Biology, The Norwegian Radium Hospital, Montebello, Oslo (Norway)

    2008-09-01T23:59:59.000Z

    Purpose: To determine the relative biologic effects (RBE) of {alpha}-particle radiation from {sup 227}Th-rituximab and of {beta}-radiation from {sup 90}Y-tiuexetan-ibritumomab (Zevalin) compared with external beam X-radiation in the Raji lymphoma xenograft model. Methods and Materials: Radioimmunoconjugates were administered intravenously in nude mice with Raji lymphoma xenografts at different levels of activity. Absorbed dose to tumor was estimated by separate biodistribution experiments for {sup 227}Th-rituximab and Zevalin. Tumor growth was measured two to three times per week after injection or X-radiation. Treatment-induced increase in growth delay to reach tumor volumes of 500 and 1,000 mm{sup 3}, respectively, was used as an end point. Results: The absorbed radiation dose-rate in tumor was slightly more than 0.1 Gy/d for the first week following injection of {sup 227}Th-rituximab, and thereafter gradually decreased to 0.03 Gy/d at 21 days after injection. For treatment with Zevalin the maximum dose-rate in tumor was achieved already 6 h after injection (0.2 Gy/d), and thereafter decreased to 0.01 Gy/d after 7 days. The relative biologic effect was between 2.5 and 7.2 for {sup 227}Th-rituximab and between 1 and 1.3 for Zevalin. Conclusions: Both at low doses and low-dose-rates, the {sup 227}Th-rituximab treatment was more effective per absorbed radiation dose unit than the two other treatments. The considerable effect at low doses suggests that the best way to administer low-dose-rates, {alpha}-emitting radioimmunoconjugates is via multiple injections.

  13. 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

  14. Direct 2-Arm Comparison Shows Benefit of High-Dose-Rate Brachytherapy Boost vs External Beam Radiation Therapy Alone for Prostate Cancer

    SciTech Connect (OSTI)

    Khor, Richard [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, and University of Melbourne, Melbourne (Australia)] [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, and University of Melbourne, Melbourne (Australia); Duchesne, Gillian [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, and University of Melbourne, Melbourne (Australia) [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, and University of Melbourne, Melbourne (Australia); Monash University, Melbourne (Australia); Tai, Keen-Hun; Foroudi, Farshad; Chander, Sarat; Van Dyk, Sylvia; Garth, Margaret [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, and University of Melbourne, Melbourne (Australia)] [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, and University of Melbourne, Melbourne (Australia); Williams, Scott, E-mail: Scott.Williams@petermac.org [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, and University of Melbourne, Melbourne (Australia)] [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, and University of Melbourne, Melbourne (Australia)

    2013-03-01T23:59:59.000Z

    Purpose: To evaluate the outcomes of patients treated for intermediate- and high-risk prostate cancer with a single schedule of either external beam radiation therapy (EBRT) and high-dose-rate brachytherapy (HDRB) boost or EBRT alone. Methods and Materials: From 2001-2006, 344 patients received EBRT with HDRB boost for definitive treatment of intermediate- or high-risk prostate cancer. The prescribed EBRT dose was 46 Gy in 23 fractions, with a HDR boost of 19.5 Gy in 3 fractions. This cohort was compared to a contemporaneously treated cohort who received EBRT to 74 Gy in 37 fractions, using a matched pair analysis. Three-dimensional conformal EBRT was used. Matching was performed using a propensity score matching technique. High-risk patients constituted 41% of the matched cohorts. Five-year clinical and biochemical outcomes were analyzed. Results: Initial significant differences in prognostic indicators between the unmatched treatment cohorts were rendered negligible after matching, providing a total of 688 patients. Median biochemical follow-up was 60.5 months. The 5-year freedom from biochemical failure was 79.8% (95% confidence interval [CI], 74.3%-85.0%) and 70.9% (95% CI, 65.4%-76.0%) for the HDRB and EBRT groups, respectively, equating to a hazard ratio of 0.59 (95% CI, 0.43-0.81, P=.0011). Interaction analyses showed no alteration in HDR efficacy when planned androgen deprivation therapy was administered (P=.95), but a strong trend toward reduced efficacy was shown compared to EBRT in high-risk cases (P=.06). Rates of grade 3 urethral stricture were 0.3% (95% CI, 0%-0.9%) and 11.8% (95% CI, 8.1%-16.5%) for EBRT and HDRB, respectively (P<.0001). No differences in clinical outcomes were observed. Conclusions: This comparison of 2 individual contemporaneously treated HDRB and EBRT approaches showed improved freedom from biochemical progression with the HDR approach. The benefit was more pronounced in intermediate- risk patients but needs to be weighed against an increased risk of urethral toxicity.

  15. 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.

  16. 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...

  17. Heat transfer pathways in underfloor air distribution (UFAD) systems

    E-Print Network [OSTI]

    Bauman, F.; Jin, H.; Webster, T.

    2006-01-01T23:59:59.000Z

    is little radiative heat transfer and little impact on thereturn air extrac- tion and heat transfer to the plenum. ItUFAD is often used and heat transfer out of the room through

  18. Radiation receiver

    DOE Patents [OSTI]

    Hunt, A.J.

    1983-09-13T23:59:59.000Z

    The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles. 5 figs.

  19. Radiation receiver

    DOE Patents [OSTI]

    Hunt, Arlon J. (Oakland, CA)

    1983-01-01T23:59:59.000Z

    The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles.

  20. Efficient Phase-Change Materials: Development of a Low-Cost Thermal Energy Storage System Using Phase-Change Materials with Enhanced Radiation Heat Transfer

    SciTech Connect (OSTI)

    None

    2011-12-05T23:59:59.000Z

    HEATS Project: USF is developing low-cost, high-temperature phase-change materials (PCMs) for use in thermal energy storage systems. Heat storage materials are critical to the energy storage process. In solar thermal storage systems, heat can be stored in these materials during the day and released at night—when the sun is not out—to drive a turbine and produce electricity. In nuclear storage systems, heat can be stored in these materials at night and released to produce electricity during daytime peak-demand hours. Most PCMs do not conduct heat very well. Using an innovative, electroless encapsulation technique, USF is enhancing the heat transfer capability of its PCMs. The inner walls of the capsules will be lined with a corrosion-resistant, high-infrared emissivity coating, and the absorptivity of the PCM will be controlled with the addition of nano-sized particles. USF’s PCMs remain stable at temperatures from 600 to 1,000°C and can be used for solar thermal power storage, nuclear thermal power storage, and other applications.

  1. Proceedings of HT2009 2009 ASME Summer Heat Transfer Conference

    E-Print Network [OSTI]

    Guo, Zhixiong "James"

    -dependent radiation and conduction bio-heat transfer model. Ultrashort pulsed radiation transport in the cylindrical a combined transient heat transfer and Pennes bio-heat transfer model is developed to simulate the heat transfer models; and concluded that the Pennes model is still the most practical for fast prediction

  2. CORQUENCH: A model for gas sparging-enhanced, melt-water, film-boiling heat transfer

    SciTech Connect (OSTI)

    Farmer, M.T.; Sienicki, J.J.; Spencer, B.W.

    1990-01-01T23:59:59.000Z

    In evaluation of severe-accident sequences for water-cooled nuclear reactors, molten core materials may be postulated to be released into the containment and accumulate on concrete. The heatup and decomposition of concrete is accompanied by the release of water vapor and carbon dioxide gases. Gases flowing through the melt upper surface can influence the rates of heat transfer to water overlying the melt. In particular, the gas flow through the interface can be envisioned to enhance the heat removal from the melt. A mechanistic model (CORQUENCH) has been developed to describe film-boiling heat transfer between a molten pool and an overlying coolant layer in the presence of sparging gas. The model favorably predicts the lead-Feron 11 data of Greene and Greene et al. for which the calculations indicate that area enhancement in the conduction heat transfer across the film is the predominant mechanism leading to augmentation in the heat flux as the gas velocity increases. Predictions for oxidic corium indicate a rapid increase in film-boiling heat flux as the gas velocity rises. The predominant mode of heat transfer for this case is radiation, and the increase in heat flux with gas velocity is primarily a result of interfacial area enhancement of the radiation component of the overall heat transfer coefficient. The CORQUENCH model has been incorporated into the MELTSPREAD-1 computer code{sup 6} for the analysis of transient spreading in containments.

  3. Impurity feedback control for enhanced divertor and edge radiation in DIII-D discharges

    SciTech Connect (OSTI)

    Jackson, G.L.; Staebler, G.M.; Allen, S.L. [and others

    1996-10-01T23:59:59.000Z

    Long pulse and steady state fusion ignition devices will require a significant radiated power fraction to minimize heat flux to, and sputtering of, the first wall. While impurity gases have been proposed to enhance radiation, precise control of impurity gas injection is essential to achieve an adequate radiative power fraction while maintaining good energy confinement and low central impurity concentration. We report here the first experiments in the DIII-D tokamak using feedback control of the rate of impurity gas injection. These experiments were carried out with active divertor pumping using the in-situ DIII-D cryopump. The radiated power fraction was controlled by sensing either UN edge line radiation (Ne{sup +7}) or mantle radiation from selected bolometer channels and using the DIII-D digital plasma control system to calculate radiated power real-time and generate an error signal to control an impurity gas injector valve.

  4. Progress Report for Proposal entitled " The Direct Radiative Forcing of Biomass Burning Aerosols: Investigations during

    E-Print Network [OSTI]

    Progress Report for Proposal entitled " The Direct Radiative Forcing of Biomass Burning Aerosols irradiances (DSWI) at the surface and the atmospheric heating/cooling rate profiles. For example, the DSWI the Clouds and the Earth's Radiant Energy System (CERES) instrument from the Tropical Rainfall Measuring

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. Enhanced heat transfer for thermionic power modules

    SciTech Connect (OSTI)

    Johnson, D.C.

    1981-07-01T23:59:59.000Z

    The thermionic power module is capable of operating at very high heat fluxes, which in turn serve to reduce capital costs. The most efficient operation also requires uniform heat fluxes. The development of enhanced heat transfer systems is required to meet the demand for high heat fluxes (>20 w/cm/sup 2/) at high temperatures (>1500K) which advanced thermionic power modules place upon combustion systems. Energy transfer from the hot combustion gases may take place by convection, radiation, or a combination of radiation and convection. Enhanced convective heat transfer with a jet impingement system has been demonstrated in a thermionic converter. The recently-developed cellular ceramic radiative heat transfer system has also been applied to a thermionic converter. By comparing the jet impingement and cellular ceramic radiative heat transfer systems, an appropriate system may be selected for utilization in advanced thermionic power modules. Results are reported.

  10. 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...

  11. 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.

  12. Thermal response of a flat heat pipe sandwich structure to a localized heat flux

    E-Print Network [OSTI]

    Wadley, Haydn

    The temperature distribution across a flat heat pipe sandwich structure, subjected to an intense localized thermal metal foam wick and distilled water as the working fluid. Heat was applied via a propane torch and radiative heat transfer. A novel method was developed to estimate experimentally, the heat flux distribution

  13. 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...

  14. 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...

  15. ME 339 Heat Transfer ABET EC2000 syllabus

    E-Print Network [OSTI]

    Ben-Yakar, Adela

    ME 339­ Heat Transfer Page 1 ABET EC2000 syllabus ME 339 ­ Heat Transfer Spring 2010 Required convection; radiation; introduction to phase change heat transfer and to heat exchangers. Prerequisite(s): ME, Fundamentals of Heat and Mass Transfer, 6th ed., Wiley Other Required Material: NA Course Objectives

  16. Fourier analysis of conductive heat transfer for glazed roofing materials

    SciTech Connect (OSTI)

    Roslan, Nurhana Lyana; Bahaman, Nurfaradila; Almanan, Raja Noorliyana Raja; Ismail, Razidah [Faculty of Computer and Mathematical Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor (Malaysia); Zakaria, Nor Zaini [Faculty of Applied Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor (Malaysia)

    2014-07-10T23:59:59.000Z

    For low-rise buildings, roof is the most exposed surface to solar radiation. The main mode of heat transfer from outdoor via the roof is conduction. The rate of heat transfer and the thermal impact is dependent on the thermophysical properties of roofing materials. Thus, it is important to analyze the heat distribution for the various types of roofing materials. The objectives of this paper are to obtain the Fourier series for the conductive heat transfer for two types of glazed roofing materials, namely polycarbonate and polyfilled, and also to determine the relationship between the ambient temperature and the conductive heat transfer for these materials. Ambient and surface temperature data were collected from an empirical field investigation in the campus of Universiti Teknologi MARA Shah Alam. The roofing materials were installed on free-standing structures in natural ventilation. Since the temperature data are generally periodic, Fourier series and numerical harmonic analysis are applied. Based on the 24-point harmonic analysis, the eleventh order harmonics is found to generate an adequate Fourier series expansion for both glazed roofing materials. In addition, there exists a linear relationship between the ambient temperature and the conductive heat transfer for both glazed roofing materials. Based on the gradient of the graphs, lower heat transfer is indicated through polyfilled. Thus polyfilled would have a lower thermal impact compared to polycarbonate.

  17. Investigating AGN Heating in a Sample of Nearby Clusters

    E-Print Network [OSTI]

    Dunn, R J H

    2006-01-01T23:59:59.000Z

    We analyse those objects in the Brightest 55 sample of clusters of galaxies which have a short central cooling time and a central temperature drop. Such clusters are likely to require some form of heating. Where clear radio bubbles are observed in these clusters, their energy injection is compared to the X-ray cooling rate. Of the 20 clusters requiring heating, at least 14 have clear bubbles, implying a duty cycle for the bubbling activity of at least 70 per cent. The average distance out to which the bubbles can offset the X-ray cooling, r_heat is given by r_heat/r_cool=0.86+/-0.11 where r_cool is defined as the radius as which the radiative cooling time is 3 Gyr. 10 out of 16 clusters have r_heat/r_cool>1, but there is a large range in values. The clusters which require heating but show no clear bubbles were combined with those clusters which have a radio core to form a second sub-sample. Using r_heat=0.86 r_cool we calculate the size of an average bubble expected in these clusters. In five cases (3C129.1, ...

  18. Using Cool Roofs to Reduce Energy Use, Greenhouse Gas Emissions, and Urban Heat-island Effects: Findings from an India Experiment

    E-Print Network [OSTI]

    Akbari, Hashem

    2011-01-01T23:59:59.000Z

    heat fluxes, solar radiation, and electric power consumed byheat fluxes, solar radiation, and electric power consumed byheat fluxes, solar radiation, and electric power consumed by

  19. Radiatively Important Parameters Best Estimate (RIPBE): An ARM Value-Added Product

    SciTech Connect (OSTI)

    McFarlane, S; Shippert, T; Mather, J

    2011-06-30T23:59:59.000Z

    The Radiatively Important Parameters Best Estimate (RIPBE) VAP was developed to create a complete set of clearly identified set of parameters on a uniform vertical and temporal grid to use as input to a radiative transfer model. One of the main drivers for RIPBE was as input to the Broadband Heating Rate Profile (BBHRP) VAP, but we also envision using RIPBE files for user-run radiative transfer codes, as part of cloud/aerosol retrieval testbeds, and as input to averaged datastreams for model evaluation.

  20. 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.

  1. Circumnuclear Media and Accretion Rates of Quiescent Supermassive Black Holes

    E-Print Network [OSTI]

    Generozov, Aleksey; Metzger, Brian D

    2015-01-01T23:59:59.000Z

    We calculate steady-state, one-dimensional hydrodynamic profiles of hot gas in slowly accreting ("quiescent") galactic nuclei for a range of central black hole masses, parameterized gas heating rates, and observationally-motivated stellar density profiles. Mass is supplied to the circumnuclear medium by stellar winds, while energy is injected primarily by stellar winds, supernovae, and black hole feedback. Analytic estimates are derived for the stagnation radius (where the radial velocity of the gas passes through zero) and the black hole accretion rate, as a function of the black hole mass and the gas heating efficiency, the latter being related to the star-formation history. We assess the conditions under which radiative instabilities develop in the hydrostatic region near the stagnation radius, both in the case of a single burst of star formation and for the average star formation history predicted by cosmological simulations. By combining a sample of measured nuclear X-ray luminosities from nearby quiesce...

  2. Radiative rates for E1, E2, M1, and M2 transitions in the Br-like ions Sr IV, Y V, Zr VI, Nb VII, and Mo VIII

    E-Print Network [OSTI]

    Aggarwal, K M

    2015-01-01T23:59:59.000Z

    Energies and lifetimes are reported for the lowest 375 levels of five Br-like ions, namely Sr~IV, Y~V, Zr~VI, Nb~VII, and Mo~VIII, mostly belonging to the 4s$^2$4p$^5$, 4s$^2$4p$^4$4$\\ell$, 4s4p$^6$, 4s$^2$4p$^4$5$\\ell$, 4s$^2$4p$^3$4d$^2$, 4s4p$^5$4$\\ell$, and 4s4p$^5$5$\\ell$ configurations. Extensive configuration interaction has been included and the general-purpose relativistic atomic structure package ({\\sc grasp}) has been adopted for the calculations. Additionally, radiative rates are listed among these levels for all E1, E2, M1, and M2 transitions. From a comparison with the measurements, the majority of our energy levels are assessed to be accurate to better than 2\\%, although discrepancies between theory and experiment for a few are up to 6\\%. An accuracy assessment of the calculated radiative rates (and lifetimes) is more difficult, because no prior results exist for these ions.

  3. Radiation events in astronomical CCD images

    E-Print Network [OSTI]

    2001-01-01T23:59:59.000Z

    268. 10. “On the Rates of Radiation Events in CCD’s (Excerpt23 Jan 2002 LBNL-49316 Radiation events in astronomical CCDof depleted silicon to ionizing radiation is a nuisance to

  4. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, L.H.

    1994-08-16T23:59:59.000Z

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

  5. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, Louis H. (Knoxville, TN)

    1995-01-01T23:59:59.000Z

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode.

  6. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, L.H.

    1995-10-17T23:59:59.000Z

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

  7. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, Louis H. (Knoxville, TN)

    1994-01-01T23:59:59.000Z

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode.

  8. Alkali Metal Heat Pipe Life Issues

    SciTech Connect (OSTI)

    Reid, Robert S. [Marshall Space Flight Center, National Aeronautics and Space Administration, Huntsville, Alabama, 35812 (United States)

    2004-07-01T23:59:59.000Z

    One approach to fission power system design uses alkali metal heat pipes for the core primary heat-transfer system. Heat pipes may also be used as radiator elements or auxiliary thermal control elements. This synopsis characterizes long-life core heat pipes. References are included where information that is more detailed can be found. Specifics shown here are for demonstration purposes and do not necessarily reflect current Nasa Project Prometheus point designs. (author)

  9. A Phase II Trial of Neoadjuvant Preoperative Chemoradiotherapy With S-1 Plus Irinotecan and Radiation in Patients With Locally Advanced Rectal Cancer: Clinical Feasibility and Response Rate

    SciTech Connect (OSTI)

    Sato, Takeo; Ozawa, Heita; Hatate, Kazuhiko; Onosato, Wataru; Naito, Masanori; Nakamura, Takatoshi; Ihara, Atsushi [Department of Surgery, Kitasato University School of Medicine, Kanagawa (Japan); Koizumi, Wasaburo [Department of Internal Medicine, Kitasato University School of Medicine, Kanagawa (Japan); Hayakawa, Kazushige [Department of Radiology, Kitasato University School of Medicine, Kanagawa (Japan); Okayasu, Isao [Department of Pathology, Kitasato University School of Medicine, Kanagawa (Japan); Yamashita, Keishi [Department of Surgery, Kitasato University School of Medicine, Kanagawa (Japan); Watanabe, Masahiko, E-mail: rint@kitasato-u.ac.j [Department of Surgery, Kitasato University School of Medicine, Kanagawa (Japan)

    2011-03-01T23:59:59.000Z

    Purpose: We aimed to validate our hypothesis that a preoperative chemoradiotherapy regimen with S-1 plus irinotecan is feasible, safe, and active for the management of locally advanced rectal cancer in a single-arm Phase II setting. Methods and Materials: Eligible patients had previously untreated, locally advanced rectal adenocarcinoma. Radiotherapy was administered in fractions of 1.8Gy/d for 25 days. S-1 was administered orally in a fixed daily dose of 80mg/m{sup 2} on Days 1 to 5, 8 to 12, 22 to 26, and 29 to 33. Irinotecan (80mg/m{sup 2}) was infused on Days 1, 8, 22, and 29. Four or more weeks after the completion of the treatment, total mesorectal excision with lateral lymph node dissection was performed. The primary endpoint was the rate of completing treatment in terms of feasibility. The secondary endpoints were the response rate and safety. Results: We enrolled 43 men and 24 women in the study. The number of patients who completed treatment was 58 (86.6%). Overall, 46 patients (68.7%) responded to treatment and 24 (34.7%) had a complete histopathologic response. Three patients had Grade 3 leukopenia, and another three patients had Grade 3 neutropenia. Diarrhea was the most common type of nonhematologic toxicity: 3 patients had Grade 3 diarrhea. Conclusions: A preoperative regimen of S-1, irinotecan, and radiotherapy to the rectum was feasible, and it appeared safe and effective in this nonrandomized Phase II setting. It exhibited a low incidence of adverse events, a high rate of completion of treatment, and an extremely high rate of pathologic complete response.

  10. 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...

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 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

  17. 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...

  18. A Phase I/II Trial of Intensity Modulated Radiation (IMRT) Dose Escalation With Concurrent Fixed-dose Rate Gemcitabine (FDR-G) in Patients With Unresectable Pancreatic Cancer

    SciTech Connect (OSTI)

    Ben-Josef, Edgar, E-mail: edgar.ben-josef@uphs.upenn.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Schipper, Mathew [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Francis, Isaac R. [Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States); Hadley, Scott; Ten-Haken, Randall; Lawrence, Theodore; Normolle, Daniel [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Simeone, Diane M.; Sonnenday, Christopher [Department of Surgery, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Surgery, University of Michigan, Ann Arbor, Michigan (United States); Abrams, Ross [Department of Radiation Oncology, Rush Medical Center, Chicago, Illinois (United States)] [Department of Radiation Oncology, Rush Medical Center, Chicago, Illinois (United States); Leslie, William [Division of Hematology Oncology, Department of Internal Medicine, Rush Medical Center, Chicago, Illinois (United States)] [Division of Hematology Oncology, Department of Internal Medicine, Rush Medical Center, Chicago, Illinois (United States); Khan, Gazala; Zalupski, Mark M. [Division of Hematology Oncology, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan (United States)] [Division of Hematology Oncology, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan (United States)

    2012-12-01T23:59:59.000Z

    Purpose: Local failure in unresectable pancreatic cancer may contribute to death. We hypothesized that intensification of local therapy would improve local control and survival. The objectives were to determine the maximum tolerated radiation dose delivered by intensity modulated radiation with fixed-dose rate gemcitabine (FDR-G), freedom from local progression (FFLP), and overall survival (OS). Methods and Materials: Eligibility included pathologic confirmation of adenocarcinoma, radiographically unresectable, performance status of 0-2, absolute neutrophil count of {>=}1500/mm{sup 3}, platelets {>=}100,000/mm{sup 3}, creatinine <2 mg/dL, bilirubin <3 mg/dL, and alanine aminotransferase/aspartate aminotransferase {<=}2.5 Multiplication-Sign upper limit of normal. FDR-G (1000 mg/m{sup 2}/100 min intravenously) was given on days -22 and -15, 1, 8, 22, and 29. Intensity modulated radiation started on day 1. Dose levels were escalated from 50-60 Gy in 25 fractions. Dose-limiting toxicity was defined as gastrointestinal toxicity grade (G) {>=}3, neutropenic fever, or deterioration in performance status to {>=}3 between day 1 and 126. Dose level was assigned using TITE-CRM (Time-to-Event Continual Reassessment Method) with the target dose-limiting toxicity (DLT) rate set to 0.25. Results: Fifty patients were accrued. DLTs were observed in 11 patients: G3/4 anorexia, nausea, vomiting, and/or dehydration (7); duodenal bleed (3); duodenal perforation (1). The recommended dose is 55 Gy, producing a probability of DLT of 0.24. The 2-year FFLP is 59% (95% confidence interval [CI]: 32-79). Median and 2-year overall survival are 14.8 months (95% CI: 12.6-22.2) and 30% (95% CI 17-45). Twelve patients underwent resection (10 R0, 2 R1) and survived a median of 32 months. Conclusions: High-dose radiation therapy with concurrent FDR-G can be delivered safely. The encouraging efficacy data suggest that outcome may be improved in unresectable patients through intensification of local therapy.

  19. A study of contact angles in porous solids using heat pipes

    E-Print Network [OSTI]

    Collins, Richard Clark

    1971-01-01T23:59:59.000Z

    Aviation and Space Conference, 1968, 655-658. 25 Brosens, P. , "Thermionic Converters with Heat Pipe Radiators, " Advances in Energy Conversion Engineering, 1967, 181-187. 33 26 Werner, R. W. , and G. A. Carlson, "Heat Pipe Radiator for Space Power... heat from a nuclear source to a thermionic generator (~29 , since thermionic generators are sensitive to high levels of radiation. Heat pipes have been suggested for controlling cryogenic boiloff in space (~30 . An investigation of using heat pipes...

  20. Numerical investigation of the heating process inside an industrial furnace

    E-Print Network [OSTI]

    Wolper, Pierre

    Numerical investigation of the heating process inside an industrial furnace Proposition: Combined furnace taking into account convective, conductive and radiative heat transfer. The model: Catalysis, Energy Materials, Performance Materials and Recycling. Each business area is divided into market

  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. A FAST MULTILEVEL ALGORITHM FOR THE SOLUTION OF NONLINEAR SYSTEMS OF CONDUCTIVERADIATIVE HEAT TRANSFER EQUATIONS \\Lambda

    E-Print Network [OSTI]

    ­differential equations that model steady­state combined conductive­radiative heat transfer. This system of equations­Brakhage algorithm. Key words. conductive­radiative heat transfer, multilevel algorithm, compact fixed point problems integro­differential equations that model steady­state combined conductive­radiative heat transfer

  3. Radiation dosimeters

    DOE Patents [OSTI]

    Hoelsher, James W. (Pullman, WA); Hegland, Joel E. (Pullman, WA); Braunlich, Peter F. (Pullman, WA); Tetzlaff, Wolfgang (Pullman, WA)

    1992-01-01T23:59:59.000Z

    Radiation dosimeters and dosimeter badges. The dosimeter badges include first and second parts which are connected to join using a securement to produce a sealed area in which at least one dosimeter is held and protected. The badge parts are separated to expose the dosimeters to a stimulating laser beam used to read dose exposure information therefrom. The badge is constructed to allow automated disassembly and reassembly in a uniquely fitting relationship. An electronic memory is included to provide calibration and identification information used during reading of the dosimeter. Dosimeter mounts which reduce thermal heating requirements are shown. Dosimeter constructions and production methods using thin substrates and phosphor binder-layers applied thereto are also taught.

  4. 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.

  5. asme heat transfer: Topics by E-print Network

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

    fundamental laws of heat transfer (conduction, convection and radiation) and give useful data specific to cryogenic conditions (thermal contact resistance, total emissivity of...

  6. Sea surface exchanges of momentum, heat, and freshwater determined by satellite remote sensing

    E-Print Network [OSTI]

    Yu, Lisan

    1 Sea surface exchanges of momentum, heat, and freshwater determined by satellite remote sensing Freshwater flux Latent heat flux Longwave radiation Satellite remote sensing Sea surface flux estimation Sensible heat flux Shortwave radiation Surface wind fields 2 #12;Sea surface exchanges of momentum, heat

  7. 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.

  8. Thermostatic Radiator Valve Evaluation

    SciTech Connect (OSTI)

    Dentz, Jordan [Advanced Residential Integrated Energy Solutions Collaborative, New York, NY (United States); Ansanelli, Eric [Advanced Residential Integrated Energy Solutions Collaborative, New York, NY (United States)

    2015-01-01T23:59:59.000Z

    A large stock of multifamily buildings in the Northeast and Midwest are heated by steam distribution systems. Losses from these systems are typically high and a significant number of apartments are overheated much of the time. Thermostatically controlled radiator valves (TRVs) are one potential strategy to combat this problem, but have not been widely accepted by the residential retrofit market.

  9. Protoplanetary disks including radiative feedback from accreting planets

    E-Print Network [OSTI]

    Montesinos, Matias; Perez, Sebastian; Baruteau, Clement; Casassus, Simon

    2015-01-01T23:59:59.000Z

    While recent observational progress is converging on the detection of compact regions of thermal emission due to embedded protoplanets, further theoretical predictions are needed to understand the response of a protoplanetary disk to the planet formation radiative feedback. This is particularly important to make predictions for the observability of circumplanetary regions. In this work we use 2D hydrodynamical simulations to examine the evolution of a viscous protoplanetary disk in which a luminous Jupiter-mass planet is embedded. We use an energy equation which includes the radiative heating of the planet as an additional mechanism for planet formation feedback. Several models are computed for planet luminosities ranging from $10^{-5}$ to $10^{-3}$ Solar luminosities. We find that the planet radiative feedback enhances the disk's accretion rate at the planet's orbital radius, producing a hotter and more luminous environement around the planet, independently of the prescription used to model the disk's turbul...

  10. Radiation beam calorimetric power measurement system

    DOE Patents [OSTI]

    Baker, John (Livermore, CA); Collins, Leland F. (Pleasanton, CA); Kuklo, Thomas C. (Ripon, CA); Micali, James V. (Dublin, CA)

    1992-01-01T23:59:59.000Z

    A radiation beam calorimetric power measurement system for measuring the average power of a beam such as a laser beam, including a calorimeter configured to operate over a wide range of coolant flow rates and being cooled by continuously flowing coolant for absorbing light from a laser beam to convert the laser beam energy into heat. The system further includes a flow meter for measuring the coolant flow in the calorimeter and a pair of thermistors for measuring the temperature difference between the coolant inputs and outputs to the calorimeter. The system also includes a microprocessor for processing the measured coolant flow rate and the measured temperature difference to determine the average power of the laser beam.

  11. 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...

  12. 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...

  13. Heat loss from an open cavity

    SciTech Connect (OSTI)

    McDonald, C.G. [California State Polytechnic Univ., Pomona, CA (United States). Coll. of Engineering

    1995-12-01T23:59:59.000Z

    Cavity type receivers are used extensively in concentrating solar thermal energy collecting systems. The Solar Total Energy Project (STEP) in Shenandoah, Georgia is a large scale field test for the collection of solar thermal energy. The STEP experiment consists of a large field array of solar collectors used to supplement the process steam, cooling and other electrical power requirements of an adjacent knitwear manufacturing facility. The purpose of the tests, conducted for this study, was to isolate and quantify the radiative, conductive, and convective components of total heat loss, and to determine the effects of operating temperature, receiver angle, and aperture size on cavity heat loss. An analytical model for radiative heat loss was developed and compared with two other methods used to determine radiative heat loss. A proposed convective heat loss correlation, including effects of aperture size, receiver operating temperature, and receiver angle is presented. The resulting data is a source to evaluate the STEP measurements.

  14. Radiative Flow in a Luminous Disk II

    E-Print Network [OSTI]

    Jun Fukue

    2006-01-07T23:59:59.000Z

    Radiatively-driven transfer flow perpendicular to a luminous disk is examined in the subrelativistic regime of $(v/c)^1$, taking into account the gravity of the central object. The flow is assumed to be vertical, and the gas pressure is ignored, while internal heating is assumed to be proportional to the gas density. The basic equations were numerically solved as a function of the optical depth, and the flow velocity, the height, the radiative flux, and the radiation pressure were obtained for a given radius, an initial optical depth, and initial conditions at the flow base (disk ``inside''), whereas the mass-loss rate was determined as an eigenvalue of the boundary condition at the flow top (disk ``surface''). For sufficiently luminous cases, the flow resembles the case without gravity. For less-luminous cases, however, the flow velocity decreases, and the flow would be impossible due to the existence of gravity in the case that the radiative flux is sufficiently small. Application to a supercritical accretion disk with mass loss is briefly discussed.

  15. Extreme-ultraviolet radiation transport in small scale length laser-produced tin plasmas

    E-Print Network [OSTI]

    Sequoia, Kevin Lamar Williams

    2009-01-01T23:59:59.000Z

    radiation heated sio2 aerogel plasma in "dog-bone" targetsspectra from Ti-doped aerogels. Journal of Quantitative

  16. Diagnostic options for radiative divertor feedback control on NSTX-U

    SciTech Connect (OSTI)

    Soukhanovskii, V. A.; McLean, A. G. [Lawrence Livermore National Laboratory, Livermore, California, 94550 (United States); Gerhardt, S. P.; Kaita, R. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540 (United States); Raman, R. [University of Washington, Seattle, Washington 98195 (United States)

    2012-10-15T23:59:59.000Z

    A radiative divertor technique is used in present tokamak experiments and planned for ITER to mitigate high heat loads on divertor plasma-facing components (PFCs) to prevent excessive material erosion and thermal damage. In NSTX, a large spherical tokamak with lithium-coated graphite PFCs and high divertor heat flux (q{sub peak} Less-Than-Or-Slanted-Equal-To 15 MW/m{sup 2}), radiative divertor experiments have demonstrated a significant reduction of divertor peak heat flux simultaneously with good core H-mode confinement using pre-programmed D{sub 2} or CD{sub 4} gas injections. In this work diagnostic options for a new real-time feedback control system for active radiative divertor detachment control in NSTX-U, where steady-state peak divertor heat fluxes are projected to reach 20-30 MW/m{sup 2}, are discussed. Based on the NSTX divertor detachment measurements and analysis, the control diagnostic signals available for NSTX-U include divertor radiated power, neutral pressure, spectroscopic deuterium recombination signatures, infrared thermography of PFC surfaces, and thermoelectric scrape-off layer current. In addition, spectroscopic 'security' monitoring of possible confinement or pedestal degradation is recommended. These signals would be implemented in a digital plasma control system to manage the divertor detachment process via an actuator (impurity gas seeding rate).

  17. Radiation: Radiation Control (Indiana)

    Broader source: Energy.gov [DOE]

    It is the policy of the state to encourage the constructive uses of radiation and to control its harmful effects. This section contains regulations pertaining to the manufacture, use,...

  18. Local thermodynamic equilibrium in rapidly heated high energy density plasmas

    SciTech Connect (OSTI)

    Aslanyan, V.; Tallents, G. J. [York Plasma Institute, Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom)

    2014-06-15T23:59:59.000Z

    Emission spectra and the dynamics of high energy density plasmas created by optical and Free Electron Lasers (FELs) depend on the populations of atomic levels. Calculations of plasma emission and ionization may be simplified by assuming Local Thermodynamic Equilibrium (LTE), where populations are given by the Saha-Boltzmann equation. LTE can be achieved at high densities when collisional processes are much more significant than radiative processes, but may not be valid if plasma conditions change rapidly. A collisional-radiative model has been used to calculate the times taken by carbon and iron plasmas to reach LTE at varying densities and heating rates. The effect of different energy deposition methods, as well as Ionization Potential Depression are explored. This work shows regimes in rapidly changing plasmas, such as those created by optical lasers and FELs, where the use of LTE is justified, because timescales for plasma changes are significantly longer than the times needed to achieve an LTE ionization balance.

  19. 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...

  20. 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%.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. Superradiant Quantum Heat Engine

    E-Print Network [OSTI]

    Ali Ü. C. Hardal; Özgür E. Müstecapl?oglu

    2015-04-22T23:59:59.000Z

    Quantum physics revolutionized classical disciplines of mechanics, statistical physics, and electrodynamics. One branch of scientific knowledge however seems untouched: thermodynamics. Major motivation behind thermodynamics is to develop efficient heat engines. Technology has a trend to miniaturize engines, reaching to quantum regimes. Development of quantum heat engines (QHEs) requires emerging field of quantum thermodynamics. Studies of QHEs debate whether quantum coherence can be used as a resource. We explore an alternative where it can function as an effective catalyst. We propose a QHE which consists of a photon gas inside an optical cavity as the working fluid and quantum coherent atomic clusters as the fuel. Utilizing the superradiance, where a cluster can radiate quadratically faster than a single atom, we show that the work output becomes proportional to the square of the number of the atoms. In addition to practical value of cranking up QHE, our result is a fundamental difference of a quantum fuel from its classical counterpart.

  6. Effervescent heating: constraints from nearby cooling flow clusters observed with XMM-Newton

    E-Print Network [OSTI]

    Rocco Piffaretti; Jelle Kaastra

    2006-05-15T23:59:59.000Z

    We have used deprojected radial density and temperature profiles of a sample of 16 nearby CF clusters observed with XMM-Newton to test whether the effervescent heating model can satisfactorily explain the dynamics of CF clusters. For each cluster we derived the required extra heating as a function of cluster-centric distance for various values of the unknown parameters $\\dot M$ (mass deposition rate) and $f_c$ (conduction efficiency). We fitted the extra heating curve using the AGN effervescent heating function and derived the AGN parameters $L$ (the time-averaged luminosity) and $r_0$ (the scale radius where the bubbles start rising in the ICM). While we do not find any solution with the effervescent heating model for only one object, we do show that AGN and conduction heating are not cooperating effectively for half of the objects in our sample. For most of the clusters we find that, when a comparison is possible, the derived AGN scale radius $r_0$ and the observed AGN jet extension have the same order of magnitude. The AGN luminosities required to balance radiative losses are substantially lowered if the fact that the AGN deposits energy within a finite volume is taken into account. For the Virgo cluster, we find that the AGN power derived from the effervescent heating model is in good agreement with the observed jet power.

  7. FRAGMENTATION AND EVOLUTION OF MOLECULAR CLOUDS. II. THE EFFECT OF DUST HEATING

    SciTech Connect (OSTI)

    Urban, Andrea; Evans, Neal J. [Department of Astronomy, University of Texas, Austin, TX 78712 (United States); Martel, Hugo [Departement de Physique, genie physique et optique, Universite Laval, Quebec, QC G1K 7P4 (Canada)

    2010-02-20T23:59:59.000Z

    We investigate the effect of heating by luminosity sources in a simulation of clustered star formation. Our heating method involves a simplified continuum radiative transfer method that calculates the dust temperature. The gas temperature is set by the dust temperature. We present the results of four simulations; two simulations assume an isothermal equation of state and the two other simulations include dust heating. We investigate two mass regimes, i.e., 84 M{sub sun} and 671 M{sub sun}, using these two different energetics algorithms. The mass functions for the isothermal simulations and simulations that include dust heating are drastically different. In the isothermal simulation, we do not form any objects with masses above 1 M{sub sun}. However, the simulation with dust heating, while missing some of the low-mass objects, forms high-mass objects ({approx}20 M{sub sun}) which have a distribution similar to the Salpeter initial mass function. The envelope density profiles around the stars formed in our simulation match observed values around isolated, low-mass star-forming cores. We find the accretion rates to be highly variable and, on average, increasing with final stellar mass. By including radiative feedback from stars in a cluster-scale simulation, we have determined that it is a very important effect which drastically affects the mass function and yields important insights into the formation of massive stars.

  8. 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.

  9. Bridging conduction and radiation : investigating thermal transport in nanoscale gaps

    E-Print Network [OSTI]

    Chiloyan, Vazrik

    2015-01-01T23:59:59.000Z

    Near field radiation transfer between objects separated by small gaps is a widely studied field in heat transfer and has become more important than ever. Many technologies such as heat assisted magnetic recording, aerogels, ...

  10. A High-Order-Accurate GPU-Based Radiative Transfer Equation Solver for Combustion and Propulsion Applications

    E-Print Network [OSTI]

    He, Xing; Lee, Euntaek; Wilcox, Lucas; Munipalli, Ramakanth; Pilon, Laurent

    2013-01-01T23:59:59.000Z

    of radiative transfer in combustion systems”, Int. J. Numer.c, “Radiation heat transfer in combustion systems”, Progressin Energy and Combustion Science, vol. 13, no. 2, pp. 97–

  11. assessing radiation feedbacks: Topics by E-print Network

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

    pressure, from both direct opticalUV radiation and multi-scattered, re-processed infrared (IR) radiation. Photo-heating smooths and thickens the disks and suppresses star...

  12. astrophysical radiation hydrodynamics: Topics by E-print Network

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

    pressure, from both direct opticalUV radiation and multi-scattered, re-processed infrared (IR) radiation. Photo-heating smooths and thickens the disks and suppresses star...

  13. accelerator radiation processing: Topics by E-print Network

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

    A; Keitel, C H; Macchi, A 2010-01-01 12 Cloud Formation and Acceleration in a Radiative Environment CERN Preprints Summary: In a radiatively heated and cooled medium, the thermal...

  14. 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

  15. 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

  16. aerosol radiative effects: Topics by E-print Network

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

    space-borne sensors use information from the ultraviolet (UV) to the visible and thermal infrared Christopher, Sundar A. 25 Black carbon radiative heating effects on cloud...

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. Heating and Acceleration of Intracluster Medium Electrons by Turbulence

    E-Print Network [OSTI]

    Vahé Petrosian; William E. East

    2008-02-06T23:59:59.000Z

    In this paper we investigate the feasibility of bremsstrahlung radiation from `nonthermal' electrons as a source of hard X-rays from the intracluster medium of clusters of galaxies. With an exact treatment of the Coulomb collisions in a Fokker-Planck analysis of the electron distribution we find that the severe difficulties with lifetimes of `nonthermal' particles found earlier by Petrosian (2001) using a cold target model remain problematic. We then address possible acceleration of background electrons into a nonthermal tail. We assume a simplified but generic acceleration rate and determine the expected evolution of an initially Maxwellian distribution of electrons. We find that strong nonthermal components arise only for rapid rate of acceleration which also heats up the entire plasma. These results confirm the conclusion that if the observed `nonthermal' excesses are due to some process accelerating the background thermal electrons this process must be short lived.

  2. 1931DECEMBER 2004AMERICAN METEOROLOGICAL SOCIETY | PROGRESS IN HEAT WATCH

    E-Print Network [OSTI]

    Sheridan, Scott

    1931DECEMBER 2004AMERICAN METEOROLOGICAL SOCIETY | H PROGRESS IN HEAT WATCH­ WARNING SYSTEM climatology-based heat watch­warning systems have been implemented across the United States in circula- tion, in order to increase heat loss through radiation, as well as evaporative cooling by sweat

  3. Heat transfer from nanoparticles: a corresponding state analysis

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    temperatures using laser heating of nanoparticles [8, 9, 10], even reaching the melting point of gold particles is relevant to experiments in which a fluid is locally heated using selective absorption of radiation by solid surfaces, lo- cal heating of fluids by selective absorption from nanoparti- cles, with possible biomedical

  4. Glass heat pipe evacuated tube solar collector

    DOE Patents [OSTI]

    McConnell, Robert D. (Lakewood, CO); Vansant, James H. (Tracy, CA)

    1984-01-01T23:59:59.000Z

    A glass heat pipe is adapted for use as a solar energy absorber in an evacuated tube solar collector and for transferring the absorbed solar energy to a working fluid medium or heat sink for storage or practical use. A capillary wick is formed of granular glass particles fused together by heat on the inside surface of the heat pipe with a water glass binder solution to enhance capillary drive distribution of the thermal transfer fluid in the heat pipe throughout the entire inside surface of the evaporator portion of the heat pipe. Selective coatings are used on the heat pipe surface to maximize solar absorption and minimize energy radiation, and the glass wick can alternatively be fabricated with granular particles of black glass or obsidian.

  5. Evaluating Radiative Closure in the Middle-to-Upper Troposhere

    SciTech Connect (OSTI)

    Tobin, David C; Turner, David D; Knuteson, Robert O

    2013-01-02T23:59:59.000Z

    This project had two general objectives. The first is the characterization and improvement of the radiative transfer parameterization in strongly absorbing water vapor bands, as these strongly absorbing bands dictate the clear sky radiative heating rate. The second is the characterization and improvement of the radiative transfer in cirrus clouds, with emphasis on ensuring that the parameterization of the radiative transfer is consistent and accurate across the spectrum. Both of these objectives are important for understanding the radiative processes in the mid-to-upper troposphere. The research on this project primarily involved analysis of data from the First and Second Radiative Heating in Underexplored Bands Campaigns, RHUBC-I and II. This included a climate model sensitivity study using results from RHUBC-I. The RHUBC experiments are ARM-funded activities that directly address the objectives of this research project. A secondary effort was also conducted that investigated the trends in the long-term (~14 year) dataset collected by the Atmospheric Emitted Radiance Interferometer (AERI) at the ARM Southern Great Plains site. This work, which was primarily done by a post-doc at the University of Wisconsin �������¢���������������� Madison under Dr. Turner�������¢����������������s direction, uses the only NIST-traceable instrument at the ARM site that has a well-documented calibration and uncertainty performance to investigate long-term trends in the downwelling longwave radiance above this site.

  6. Packet personal radiation monitor

    DOE Patents [OSTI]

    Phelps, James E. (Knoxville, TN)

    1989-01-01T23:59:59.000Z

    A personal radiation monitor of the chirper type is provided for detecting ionizing radiation. A battery powered high voltage power supply is used to generate and apply a high voltage bias to a G-M tube radiation sensor. The high voltage is monitored by a low-loss sensing network which generates a feedback signal to control the high voltage power supply such that the high voltage bias is recharged to +500 VDC when the current pulses of the sensor, generated by the detection of ionizing radiation events, discharges the high voltage bias to +450 VDC. During the high voltage recharge period an audio transducer is activated to produce an audible "chirp". The rate of the "chirps" is controlled by the rate at which the high voltage bias is recharged, which is proportional to the radiation field intensity to which the sensor is exposed. The chirp rate sensitivity is set to be approximately 1.5 (chirps/min/MR/hr.). The G-M tube sensor is used in a current sensing mode so that the device does not paralyze in a high radiation field.

  7. Developing Low-Conductance Window Frames: Capabilities and Limitations of Current Window Heat Transfer Design Tools

    SciTech Connect (OSTI)

    Gustavsen, Arild; Arasteh, Dariush; Jelle, Bjorn Petter; Curcija, Charlie; Kohler, Christian

    2008-09-11T23:59:59.000Z

    While window frames typically represent 20-30% of the overall window area, their impact on the total window heat transfer rates may be much larger. This effect is even greater in low-conductance (highly insulating) windows that incorporate very low-conductance glazing. Developing low-conductance window frames requires accurate simulation tools for product research and development. Based on a literature review and an evaluation of current methods of modeling heat transfer through window frames, we conclude that current procedures specified in ISO standards are not sufficiently adequate for accurately evaluating heat transfer through the low-conductance frames. We conclude that the near-term priorities for improving the modeling of heat transfer through low-conductance frames are: (1) Add 2D view-factor radiation to standard modeling and examine the current practice of averaging surface emissivity based on area weighting and the process of making an equivalent rectangular frame cavity. (2) Asses 3D radiation effects in frame cavities and develop recommendation for inclusion into the design fenestration tools. (3) Assess existing correlations for convection in vertical cavities using CFD. (4) Study 2D and 3D natural convection heat transfer in frame cavities for cavities that are proven to be deficient from item 3 above. Recommend improved correlations or full CFD modeling into ISO standards and design fenestration tools, if appropriate. (5) Study 3D hardware short-circuits and propose methods to ensure that these effects are incorporated into ratings. (6) Study the heat transfer effects of ventilated frame cavities and propose updated correlations.

  8. Miniaturized radiation chirper

    DOE Patents [OSTI]

    Umbarger, C. John (Los Alamos, NM); Wolf, Michael A. (Los Alamos, NM)

    1980-01-01T23:59:59.000Z

    The disclosure relates to a miniaturized radiation chirper for use with a small battery supplying on the order of 5 volts. A poor quality CdTe crystal which is not necessarily suitable for high resolution gamma ray spectroscopy is incorporated with appropriate electronics so that the chirper emits an audible noise at a rate that is proportional to radiation exposure level. The chirper is intended to serve as a personnel radiation warning device that utilizes new and novel electronics with a novel detector, a CdTe crystal. The resultant device is much smaller and has much longer battery life than existing chirpers.

  9. 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...

  10. JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER Vol. 14, No. 4, OctoberDecember 2000

    E-Print Network [OSTI]

    Guo, Zhixiong "James"

    JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER Vol. 14, No. 4, October­December 2000 Multidimensional are optical tomographyof tissue, remote sensing of oceansand atmospheres, laser material processing radiative heat transfer in participat- ing media in recent years. However, the analysis of radiative heat

  11. Spherical collapse of a heat conducting fluid in higher dimensions without horizon

    E-Print Network [OSTI]

    A. banerjee; S. Chatterjee

    2004-06-08T23:59:59.000Z

    We consider a scenario where the interior spacetime,described by a heat conducting fluid sphere is matched to a Vaidya metric in higher dimensions.Interestingly we get a class of solutions, where following heat radiation the boundary surface collapses without the appearance of an event horizon at any stage and this happens with reasonable properties of matter field.The non-occurrence of a horizon is due to the fact that the rate of mass loss exactly counterbalanced by the fall of boundary radius.Evidently this poses a counter example to the so-called cosmic censorship hypothesis.Two explicit examples of this class of solutions are also given and it is observed that the rate of collapse is delayed with the introduction of extra dimensions.The work extends to higher dimensions our previous investigation in 4D.

  12. 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.

  13. 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

  14. 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

  15. 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

  16. 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

  17. Radiation physics, biophysics, and radiation biology

    SciTech Connect (OSTI)

    Hall, E.J.; Zaider, M.

    1993-05-01T23:59:59.000Z

    Research at the Center for Radiological Research is a multidisciplenary blend of physics, chemistry and biology aimed at understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. The focus is increased on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights of the program from the past year are described. A mathematical model describing the production of single-strand and double-strand breaks in DNA as a function radiation quality has been completed. For the first time Monte Carlo techniques have been used to obtain directly the spatial distribution of DNA moieties altered by radiation. This information was obtained by including the transport codes a realistic description of the electronic structure of DNA. We have investigated structure activity relationships for the potential oncogenicity of a new generation of bioreductive drugs that function as hypoxic cytotoxins. Experimental and theoretical investigation of the inverse dose rate effect, whereby medium LET radiations actually produce an c effect when the dose is protracted, is now at a point where the basic mechanisms are reasonably understood and the complex interplay between dose, dose rate and radiation quality which is necessary for the effect to be present can now be predicted at least in vitro. In terms of early radiobiological damage, a quantitative link has been established between basic energy deposition and locally multiply damaged sites, the radiochemical precursor of DNA double strand breaks; specifically, the spatial and energy deposition requirements necessary to form LMDs have been evaluated. For the first time, a mechanically understood biological fingerprint'' of high-LET radiation has been established. Specifically measurement of the ratio of inter-to intra-chromosomal aberrations produces a unique signature from alpha-particles or neutrons.

  18. Surface Power Radiative Cooling Tests

    SciTech Connect (OSTI)

    Vaughn, Jason; Schneider, Todd [Environmental Effects Branch, EM50, NASA Marshall Space Flight Center, AL 35812 (United States)

    2006-01-20T23:59:59.000Z

    Terrestrial nuclear power plants typically maintain their temperature through convective cooling, such as water and forced air. However, the space environment is a vacuum environment, typically 10-8 Torr pressure, therefore in proposed missions to the lunar surface, power plants would have to rely on radiative cooling to remove waste heat. Also, the Martian surface has a very tenuous atmosphere (e.g. {approx}5 Torr CO2), therefore, the main heat transfer method on the Martian surface is also radiative. Because of the lack of atmosphere on the Moon and the tenuous atmosphere on Mars, surface power systems on both the Lunar and Martian surface must rely heavily on radiative heat transfer. Because of the large temperature swings on both the lunar and the Martian surfaces, trying to radiate heat is inefficient. In order to increase power system efficiency, an effort is underway to test various combinations of materials with high emissivities to demonstrate their ability to survive these degrading atmospheres to maintain a constant radiator temperature improving surface power plant efficiency. An important part of this effort is the development of a unique capability that would allow the determination of a materials emissivity at high temperatures. A description of the test capability as well as initial data is presented.

  19. The Gas-Cooled Fast Reactor: Report on Safety System Design for Decay Heat Removal

    SciTech Connect (OSTI)

    K. D. Weaver; T. Marshall; T. Y. C. Wei; E. E. Feldman; M. J. Driscoll; H. Ludewig

    2003-09-01T23:59:59.000Z

    The gas-cooled fast reactor (GFR) was chosen as one of the Generation IV nuclear reactor systems to be developed based on its excellent potential for sustainability through reduction of the volume and radiotoxicity of both its own fuel and other spent nuclear fuel, and for extending/utilizing uranium resources orders of magnitude beyond what the current open fuel cycle can realize. In addition, energy conversion at high thermal efficiency is possible with the current designs being considered, thus increasing the economic benefit of the GFR. However, research and development challenges include the ability to use passive decay heat removal systems during accident conditions, survivability of fuels and in-core materials under extreme temperatures and radiation, and economical and efficient fuel cycle processes. This report addresses/discusses the decay heat removal options available to the GFR, and the current solutions. While it is possible to design a GFR with complete passive safety (i.e., reliance solely on conductive and radiative heat transfer for decay heat removal), it has been shown that the low power density results in unacceptable fuel cycle costs for the GFR. However, increasing power density results in higher decay heat rates, and the attendant temperature increase in the fuel and core. Use of active movers, or blowers/fans, is possible during accident conditions, which only requires 3% of nominal flow to remove the decay heat. Unfortunately, this requires reliance on active systems. In order to incorporate passive systems, innovative designs have been studied, and a mix of passive and active systems appears to meet the requirements for decay heat removal during accident conditions.

  20. Radiative and climate impacts of absorbing aerosols

    E-Print Network [OSTI]

    Zhu, Aihua

    2010-01-01T23:59:59.000Z

    and less surface solar radiation in China from 1955 to 2000,2001 in China, and meanwhile, both surface solar radiationsolar heating greatly decreases RH in the lower troposphere for both China and

  1. Color-preserving daytime radiative cooling

    SciTech Connect (OSTI)

    Zhu, Linxiao [Department of Applied Physics, Stanford University, Stanford, California 94305 (United States)] [Department of Applied Physics, Stanford University, Stanford, California 94305 (United States); Raman, Aaswath; Fan, Shanhui, E-mail: shanhui@stanford.edu [Department of Electrical Engineering, Ginzton Laboratory, Stanford University, Stanford, California 94305 (United States)] [Department of Electrical Engineering, Ginzton Laboratory, Stanford University, Stanford, California 94305 (United States)

    2013-11-25T23:59:59.000Z

    We introduce a general approach to radiatively lower the temperature of a structure, while preserving its color under sunlight. The cooling effect persists in the presence of considerable convective and conductive heat exchange and for different solar absorptances.

  2. Radiation effects in a muon collider ring and dipole magnet protection

    E-Print Network [OSTI]

    Mokhov, N V; Novitski, I; Zlobin, A V

    2011-01-01T23:59:59.000Z

    The requirements and operating conditions for a Muon Collider Storage Ring (MCSR) pose significant challenges to superconducting magnets. The dipole magnets should provide a high magnetic field to reduce the ring circumference and thus maximize the number of muon collisions during their lifetime. One third of the beam energy is continuously deposited along the lattice by the decay electrons at the rate of 0.5 kW/m for a 1.5-TeV c.o.m. and a luminosity of 1034 cm-2s-1. Unlike dipoles in proton machines, the MCSR dipoles should allow this dynamic heat load to escape the magnet helium volume in the horizontal plane, predominantly towards the ring center. This paper presents the analysis and comparison of radiation effects in MCSR based on two dipole magnets designs. Tungsten masks in the interconnect regions are used in both cases to mitigate the unprecedented dynamic heat deposition and radiation in the magnet coils.

  3. Entanglement from thermal black body radiation

    E-Print Network [OSTI]

    Daniel Braun

    2005-09-06T23:59:59.000Z

    Two non--interacting quantum systems which couple to a common environment with many degrees of freedom initially in thermal equilibrium can become entangled due to the indirect interaction mediated through this heat bath. I examine here the dynamics of reservoir induced entanglement for a heat bath consisting of a thermal electro--magnetic radiation field, such as black body radiation or the cosmic microwave background, and show how the effect can be understood as result of an effective induced interaction.

  4. Process and apparatus for indirect-fired heating and drying

    DOE Patents [OSTI]

    Abbasi, Hamid Ali; Chudnovsky, Yaroslav

    2005-04-12T23:59:59.000Z

    A method for heating flat or curved surfaces comprising injecting fuel and oxidant along the length, width or longitudinal side of a combustion space formed between two flat or curved plates, transferring heat from the combustion products via convection and radiation to the surface being heated on to the material being dried/heated, and recirculating at least 20% of the combustion products to the root of the flame.

  5. 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.

  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. 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...

  8. 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...

  9. 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.

  10. 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.

  11. Packet personal radiation monitor

    DOE Patents [OSTI]

    Phelps, J.E.

    1988-03-31T23:59:59.000Z

    A personal radiation monitor of the chirper type is provided for detecting ionizing radiation. A battery powered high voltage power supply is used to generate and apply a high voltage bias to a G-M tube radiation sensor. The high voltage is monitored by a low-loss sensing network which generates a feedback signal to control the high voltage power supply such that the high voltage bias is recharged to +500 VDC when the current pulses of the sensor, generated by the detection of ionizing radiatonevents, discharges the high voltage bias to +450 VDC. During the high voltage recharge period an audio transducer is activated to produce an audible ''chirp''. The rate of the ''chirps'' is controlled by the rate at which the high voltage bias is recharged, which is proportional to the radiation field intensity to which the sensor is exposed. The chirp rate sensitivity is set to be approximately 1.5 (chirps/min/MR/hr.). The G-M tube sensor is used in a current sensing mode so that the device does not paralyze in a high radiation field. 2 figs.

  12. Radiation physics, biophysics, and radiation biology

    SciTech Connect (OSTI)

    Hall, E.J.

    1992-05-01T23:59:59.000Z

    The following research programs from the Center for Radiological Research of Columbia University are described: Design and development of a new wall-less ultra miniature proportional counter for nanodosimetry; some recent measurements of ionization distributions for heavy ions at nanometer site sizes with a wall-less proportional counter; a calculation of exciton energies in periodic systems with helical symmetry: application to a hydrogen fluoride chain; electron energy-loss function in polynucleotide and the question of plasmon excitation; a non-parametric, microdosimetric-based approach to the evaluation of the biological effects of low doses of ionizing radiation; high-LET radiation risk assessment at medium doses; high-LET radiobiological effects: increased lesion severity or increased lesion proximity; photoneutrons generated by high energy medical linacs; the biological effectiveness of neutrons; implications for radiation protection; molecular characterization of oncogenes induced by neutrons; and the inverse dose-rate effect for oncogenic transformation by charged particles is LET dependent.

  13. A container for heat treating materials in microwave ovens

    DOE Patents [OSTI]

    Holcombe, C.E.; Dykes, N.L.; Kimrey, H.D. Jr.; Mills, J.E.

    1988-01-26T23:59:59.000Z

    The efficiency of a microwave oven of a conventional two-source configuration and energy level is increased by providing the oven with a container for housing a refractory material to be treated. The container is formed to top and bottom walls transparent to microwaves while the sidewalls, in a circular configuration, are formed of a nonmetallic material opaque to microwave radiation for reflecting the radiation penetrating the top and bottom walls radially inwardly into the center of the container wherein a casket of heat-insulating material is provided for housing the material to be heat treated. The reflection of the microwave radiation from the sidewalls increases the concentration of the microwaves upon the material being heat treated while the concentration of the microwaves upon the material being heat treated while the casket retains the heat to permit the heating of the material to a substantially higher temperature than achievable in the oven without the container.

  14. Passive-solar directional-radiating cooling system

    DOE Patents [OSTI]

    Hull, J.R.; Schertz, W.W.

    1985-06-27T23:59:59.000Z

    A radiative cooling system for use with an ice-making system having a radiating surface aimed at the sky for radiating energy at one or more wavelength bands for which the atmosphere is transparent and a cover thermally isolated from the radiating surface and transparent at least to the selected wavelength or wavelengths, the thermal isolation reducing the formation of condensation on the radiating surface and/or cover and permitting the radiation to continue when the radiating surface is below the dewpoint of the atmosphere, and a housing supporting the radiating surface, cover and heat transfer means to an ice storage reservoir.

  15. Passive-solar directional-radiating cooling system

    DOE Patents [OSTI]

    Hull, John R. (Hinsdale, IL); Schertz, William W. (Batavia, IL)

    1986-01-01T23:59:59.000Z

    A radiative cooling system for use with an ice-making system having a radiating surface aimed at the sky for radiating energy at one or more wavelength bands for which the atmosphere is transparent and a cover thermally isolated from the radiating surface and transparent at least to the selected wavelength or wavelengths, the thermal isolation reducing the formation of condensation on the radiating surface and/or cover and permitting the radiation to continue when the radiating surface is below the dewpoint of the atmosphere, and a housing supporting the radiating surface, cover and heat transfer means to an ice storage reservoir.

  16. Divertor Heat Flux Mitigation in High-Performance H-mode Plasmas in the National Spherical Torus Experiment.

    SciTech Connect (OSTI)

    Soukhanovskii, V A; Maingi, R; Gates, D; Menard, J; Paul, S F; Raman, R; Roquemore, A L; Bell, R E; Bush, C; Kaita, R

    2008-09-22T23:59:59.000Z

    Experiments conducted in high-performance 1.0-1.2 MA 6 MW NBI-heated H-mode plasmas with a high flux expansion radiative divertor in NSTX demonstrate that significant divertor peak heat flux reduction and access to detachment may be facilitated naturally in a highly-shaped spherical torus (ST) configuration. Improved plasma performance with high {beta}{sub p} = 15-25%, a high bootstrap current fraction f{sub BS} = 45-50%, longer plasma pulses, and an H-mode regime with smaller ELMs has been achieved in the lower single null configuration with higher-end elongation 2.2-2.4 and triangularity 0.6-0.8. Divertor peak heat fluxes were reduced from 6-12 MW/m{sup 2} to 0.5-2 MW/m{sup 2} in ELMy H-mode discharges using high magnetic flux expansion and partial detachment of the outer strike point at several D{sub 2} injection rates, while good core confinement and pedestal characteristics were maintained. The partially detached divertor regime was characterized by a 30-60% increase in divertor plasma radiation, a peak heat flux reduction by up to 70%, measured in a 10 cm radial zone, a five-fold increase in divertor neutral pressure, and a significant volume recombination rate increase.

  17. Heat transfer mechanism with thin filaments including ceramic high temperature heat exchanger

    DOE Patents [OSTI]

    Im, Kwan H. (Naperville, IL); Ahluwalia, Rajesh K. (Burr Ridge, IL)

    1994-01-01T23:59:59.000Z

    A radiative heat transfer mechanism in a furnace having burners through which pulverized coal and air are burned producing combustion gases and contaminants. A plurality of elongated conduits are positioned inside the furnace proximate to the burners generally parallel to the flow of combustion gases in the furnace. A plurality of thin filaments are inside each of the elongated hollow conduits, the filaments having diameters in the range of from about 1 micrometer to about 1,000 micrometers and having an infrared radiation cross-section sufficient to cause the filaments to heat upon exposure to infrared radiation. Blower mechanism is associated with the elongated conduits for limiting the amount of soot and ash which deposit on the conduits to preserve the radiative and convective transfer of heat energy from the combustion gases to the conduits.

  18. Heat transfer mechanism with thin filaments including ceramic high temperature heat exchanger

    DOE Patents [OSTI]

    Im, K.H.; Ahluwalia, R.K.

    1994-10-18T23:59:59.000Z

    A radiative heat transfer mechanism in a furnace is described having burners through which pulverized coal and air are burned producing combustion gases and contaminants. A plurality of elongated conduits are positioned inside the furnace proximate to the burners generally parallel to the flow of combustion gases in the furnace. A plurality of thin filaments are inside each of the elongated hollow conduits, the filaments having diameters in the range of from about 1 micrometer to about 1,000 micrometers and having an infrared radiation cross-section sufficient to cause the filaments to heat upon exposure to infrared radiation. Blower mechanism is associated with the elongated conduits for limiting the amount of soot and ash which deposit on the conduits to preserve the radiative and convective transfer of heat energy from the combustion gases to the conduits. 7 figs.

  19. Coupled Reactor Kinetics and Heat Transfer Model for Heat Pipe Cooled Reactors

    SciTech Connect (OSTI)

    WRIGHT,STEVEN A.; HOUTS,MICHAEL

    2000-11-22T23:59:59.000Z

    Heat pipes are often proposed as cooling system components for small fission reactors. SAFE-300 and STAR-C are two reactor concepts that use heat pipes as an integral part of the cooling system. Heat pipes have been used in reactors to cool components within radiation tests (Deverall, 1973); however, no reactor has been built or tested that uses heat pipes solely as the primary cooling system. Heat pipe cooled reactors will likely require the development of a test reactor to determine the main differences in operational behavior from forced cooled reactors. The purpose of this paper is to describe the results of a systems code capable of modeling the coupling between the reactor kinetics and heat pipe controlled heat transport. Heat transport in heat pipe reactors is complex and highly system dependent. Nevertheless, in general terms it relies on heat flowing from the fuel pins through the heat pipe, to the heat exchanger, and then ultimately into the power conversion system and heat sink. A system model is described that is capable of modeling coupled reactor kinetics phenomena, heat transfer dynamics within the fuel pins, and the transient behavior of heat pipes (including the melting of the working fluid). The paper focuses primarily on the coupling effects caused by reactor feedback and compares the observations with forced cooled reactors. A number of reactor startup transients have been modeled, and issues such as power peaking, and power-to-flow mismatches, and loading transients were examined, including the possibility of heat flow from the heat exchanger back into the reactor. This system model is envisioned as a tool to be used for screening various heat pipe cooled reactor concepts, for designing and developing test facility requirements, for use in safety evaluations, and for developing test criteria for in-pile and out-of-pile test facilities.

  20. Danger radiations

    ScienceCinema (OSTI)

    None

    2011-04-25T23:59:59.000Z

    Le conférencier Mons.Hofert parle des dangers et risques des radiations, le contrôle des zones et les précautions à prendre ( p.ex. film badge), comment mesurer les radiations etc.

  1. Radiation trapping in coherent media

    E-Print Network [OSTI]

    A. B. Matsko; I. Novikova; M. O. Scully; G. R. Welch

    2001-01-31T23:59:59.000Z

    We show that the effective decay rate of Zeeman coherence, generated in a Rb87 vapor by linearly polarized laser light, increases significantly with the atomic density. We explain this phenomenon as the result of radiation trapping. Our study shows that radiation trapping must be taken into account to fully understand many electromagnetically induced transparency experiments with optically thick media.

  2. Heat Transfer between Graphene and Amorphous SiO2

    E-Print Network [OSTI]

    B. N. J. Persson; H. Ueba

    2010-07-22T23:59:59.000Z

    We study the heat transfer between graphene and amorphous SiO2. We include both the heat transfer from the area of real contact, and between the surfaces in the non-contact region. We consider the radiative heat transfer associated with the evanescent electromagnetic waves which exist outside of all bodies, and the heat transfer by the gas in the non-contact region. We find that the dominant contribution to the heat transfer result from the area of real contact, and the calculated value of the heat transfer coefficient is in good agreement with the value deduced from experimental data.

  3. 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.

  4. 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 ...

  5. 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

  6. Actively driven thermal radiation shield

    DOE Patents [OSTI]

    Madden, Norman W. (Livermore, CA); Cork, Christopher P. (Pleasant Hill, CA); Becker, John A. (Alameda, CA); Knapp, David A. (Livermore, CA)

    2002-01-01T23:59:59.000Z

    A thermal radiation shield for cooled portable gamma-ray spectrometers. The thermal radiation shield is located intermediate the vacuum enclosure and detector enclosure, is actively driven, and is useful in reducing the heat load to mechanical cooler and additionally extends the lifetime of the mechanical cooler. The thermal shield is electrically-powered and is particularly useful for portable solid-state gamma-ray detectors or spectrometers that dramatically reduces the cooling power requirements. For example, the operating shield at 260K (40K below room temperature) will decrease the thermal radiation load to the detector by 50%, which makes possible portable battery operation for a mechanically cooled Ge spectrometer.

  7. Use of photovoltaics for waste heat recovery

    DOE Patents [OSTI]

    Polcyn, Adam D

    2013-04-16T23:59:59.000Z

    A device for recovering waste heat in the form of radiated light, e.g. red visible light and/or infrared light includes a housing having a viewing window, and a photovoltaic cell mounted in the housing in a relationship to the viewing window, wherein rays of radiated light pass through the viewing window and impinge on surface of the photovoltaic cell. The housing and/or the cell are cooled so that the device can be used with a furnace for an industrial process, e.g. mounting the device with a view of the interior of the heating chamber of a glass making furnace. In this manner, the rays of the radiated light generated during the melting of glass batch materials in the heating chamber pass through the viewing window and impinge on the surface of the photovoltaic cells to generate electric current which is passed onto an electric load.

  8. Ionizing radiation detector

    DOE Patents [OSTI]

    Thacker, Louis H. (Knoxville, TN)

    1990-01-01T23:59:59.000Z

    An ionizing radiation detector is provided which is based on the principle of analog electronic integration of radiation sensor currents in the sub-pico to nano ampere range between fixed voltage switching thresholds with automatic voltage reversal each time the appropriate threshold is reached. The thresholds are provided by a first NAND gate Schmitt trigger which is coupled with a second NAND gate Schmitt trigger operating in an alternate switching state from the first gate to turn either a visible or audible indicating device on and off in response to the gate switching rate which is indicative of the level of radiation being sensed. The detector can be configured as a small, personal radiation dosimeter which is simple to operate and responsive over a dynamic range of at least 0.01 to 1000 R/hr.

  9. Investigation of a radiantly heated and cooled office with an integrated desiccant ventilation unit

    E-Print Network [OSTI]

    Gong, Xiangyang

    2009-05-15T23:59:59.000Z

    comprehensive study of several technical issues relative to radiant heating and cooling systems that have received little attention in previous research. The following aspects are covered in this dissertation: First, a heat transfer model of mullion radiators...

  10. Performance Test and Energy Saving Analysis of a Heat Pipe Dehumidifier

    E-Print Network [OSTI]

    Zhao, X.; Li, Q.; Yun, C.

    2006-01-01T23:59:59.000Z

    Heat pipe technology applied to ventilation, dryness, and cooling and heating radiator in a building is introduced in this paper. A new kind of heat pipe dehumidifier is designed and tested. The energy-saving ratio with the heat pipe dehumidifier...

  11. Performance Test and Energy Saving Analysis of a Heat Pipe Dehumidifier 

    E-Print Network [OSTI]

    Zhao, X.; Li, Q.; Yun, C.

    2006-01-01T23:59:59.000Z

    Heat pipe technology applied to ventilation, dryness, and cooling and heating radiator in a building is introduced in this paper. A new kind of heat pipe dehumidifier is designed and tested. The energy-saving ratio with the heat pipe dehumidifier...

  12. Simulation of plasmaneutral dynamics for radiation cooling

    E-Print Network [OSTI]

    Najmabadi, Farrokh

    the heat flux effectively for future power plants. That is, radiation due to impurities will lower and increase the required pumping speed con- siderably in a power plant. In principle, the plasma energySimulation of plasma­neutral dynamics for radiation cooling Bong Ju Lee , F. Najmabadi Fusion

  13. 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.

  14. Plasma Diagnostics of Active Region Evolution and Implications for Coronal Heating

    E-Print Network [OSTI]

    R. O. Milligan; P. T. Gallagher; M. Mathioudakis; F. P. Keenan; D. S. Bloomfield

    2005-09-08T23:59:59.000Z

    A detailed study is presented of the decaying solar active region NOAA 10103 observed with the Coronal Diagnostic Spectrometer (CDS), the Michelson Doppler Imager (MDI) and the Extreme-ultraviolet Imaging Telescope (EIT) onboard the Solar and Heliospheric Observatory (SOHO). Electron density maps formed using Si X (356.03A/347.41A) show that the density varies from ~10^10 cm^-3 in the active region core, to ~7x10^8 cm^-3 at the region boundaries. Over the five days of observations, the average electron density fell by ~30%. Temperature maps formed using Fe XVI(335.41A)/Fe XIV(334.18A) show electron temperatures of \\~2.34x10^6 K in the active region core, and ~2.10x10^6 K at the region boundaries. Similarly to the electron density, there was a small decrease in the average electron temperature over the five day period. The radiative, conductive, and mass flow losses were calculated and used to determine the resultant heating rate (P_H). Radiative losses were found to dominate the active region cooling process. As the region decayed, the heating rate decreased by almost a factor of five between the first and last day of observations. The heating rate was then compared to the total unsigned magnetic flux (Phi_tot), yielding a power-law of the form P_H ~ Phi_tot^(0.81 +/- 0.32). This result suggests that waves rather than nanoflares may be the dominant heating mechanism in this active region.

  15. 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

  16. 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.

  17. 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.

  18. 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...

  19. 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...

  20. Radiation Safety Edward O'Connell

    E-Print Network [OSTI]

    /Bureau of Environmental Radiation Protection (BERP) · Regulatory Compliance ­ State Sanitary 16 · Required Radiation to cause ionization depends on the energy #12;Radiation Can Cause Ionization #12;Units of Measurements millirem per year. · At 50,000 feet, the dose rate is about 1 millirem per hour. · There are areas

  1. 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.

  2. Superradiant Quantum Heat Engine

    E-Print Network [OSTI]

    Ali Ü. C. Hardal; Özgür E. Müstecapl?oglu

    2015-03-12T23:59:59.000Z

    Quantum physics has revolutionized the classical disciplines of mechanics, statistical physics, and electrodynamics. It modernized our society with many advances such as lasers and transistors. One branch of scientific knowledge however seems untouched: thermodynamics. Major motivation behind thermodynamics is to develop efficient heat engines. Technology has a trend to miniaturize engines, reaching to the quantum regimes. Inevitably, development of quantum heat engines (QHEs) requires investigations of thermodynamical principles from quantum mechanical perspective, and motivates the emerging field of quantum thermodynamics. Studies of QHEs debate on whether quantum coherence can be used as a resource. We explore an alternative that quantum coherence can be a catalyst. We propose a QHE which consists of a photon gas inside an optical cavity as the working fluid and quantum coherent atomic clusters as the fuel. Utilizing the superradiance, where a cluster can radiate quadratically faster than a single atom, we show that the work capability of the QHE becomes proportional to the square of the number of the atoms. In addition to practical value of cranking up a QHE, our results reveal a fundamental difference of a quantum fuel from its classical counterpart.

  3. 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...

  4. 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...

  5. Divertor Heat Flux Amelioration in Highly-Shaped Plasma in NSTX

    SciTech Connect (OSTI)

    Soukhanovskii, V; Maingi, R; Gates, D; Menard, J; Raman, R; Bell, R; Bush, C; Kaita, R; Kugel, H; LeBlanc, B; Paul, S; Roquemore, A

    2007-07-02T23:59:59.000Z

    Steady-state handling of divertor heat flux is a critical issue for both the International Thermonuclear Experimental Reactor and spherical torus (ST) based devices with compact high power density divertors. The ST compact divertor with a small plasma volume, a small plasma-wetted area, and a short parallel connection length can reduce the operating space of heat flux dissipation techniques based on induced edge and/or scrape-off layer (SOL) power and momentum loss, such as the radiative and dissipative divertors and radiative mantles. Access to these regimes is studied in the National Spherical Torus Experiment (NSTX) with an open geometry horizontal carbon plate divertor in 2-6 MW NBI-heated H-mode plasmas in a lower single null (LSN) configuration in a range of elongations {kappa} = 1.8-2.4 and triangularities {delta}= 0.40-0.75. Experiments conducted in a lower end {kappa}{approx}1.8-2.0 and {delta}{approx} 0.4-0.5 LSN shape using deuterium injection in the divertor region have achieved the outer strike point (OSP) peak heat flux reduction from 4-6 MW/m2 to a manageable level of 1-2 MW/m2. However, only the high-recycling radiative divertor (RD) regime was found to be compatible with good performance and H-mode confinement. A partially detached divertor (PDD) could only be obtained at a high D2 injection rate that led to an X-point MARFE formation and confinement degradation. Also in the low {kappa}{approx} 2,{delta}{approx} 0.45 shape, peak heat flux q{sub pk} and heat flux width {lambda}{sub q} scaling studies have been conducted. Similar to tokamak divertor studies, q{sub pk} was found to be a strong function of input power PNBI and plasma current Ip, and the heat flux midplane scale length {lambda}{sub q} was found to be large as compared with simple SOL models. In this paper, we report on the first experiments to assess steady-state divertor heat flux amelioration in highly shaped plasmas in NSTX.

  6. Thermal codes benchmarking: HEATING6 results

    SciTech Connect (OSTI)

    Bryan, C.B.; Childs, K.W.

    1985-08-01T23:59:59.000Z

    The Oak Ridge National Laboratory, in support of Sandia National Laboratories Transportation Technology Center, has developed solutions to four model test problems which serve as comparison benchmarks for thermal computer codes currently being used in the design and analysis of nuclear fuel shipping casks. These problems include steady-state and transient simulations; conductive, convective, and radiative heat transfer mechanisms; internal heat sources; multiple materials; and one- and two-dimensional geometries. Solutions to these model thermal problems produced by an enhanced version of HEATING6 are presented in this report. 4 refs., 19 figs., 14 tabs.

  7. 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...

  8. 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.

  9. 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.

  10. In Situ Heating of the 2007 May 19 CME Ejecta Detected by STEREO/PLASTIC and ACE

    E-Print Network [OSTI]

    Rakowski, Cara E; Lyutikov, Maxim

    2011-01-01T23:59:59.000Z

    In situ measurements of ion charge states can provide unique insight into the heating and evolution of coronal mass ejections when tested against realistic non-equilibrium ionization modeling. In this work we investigate the representation of the CME magnetic field as an expanding spheromak configuration, where the plasma heating is prescribed by the choice of anomalous resistivity and the spheromak dynamics. We chose as a test case, the 19 May 2007 CME observed by STEREO and ACE. The spheromak is an appealing physical model, because the location and degree of heating is fixed by the choice of anomalous resistivity and the spheromak expansion rate which we constrain with observations. This model can provide the heating required between 1.1$R_{\\sun}$ and earth orbit to produce charge states observed in the CME flux rope. However this source of heating in the spheromak alone has difficulty accounting for the rapid heating to Fe$^{8 - 11+}$ at lower heights, as observed in STEREO EUVI due to the rapid radiative ...

  11. 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

  12. 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.

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. 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,...

  18. 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...

  19. 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...

  20. Heating and Ionization of the Primordial Intergalactic Medium by High Mass X-ray Binaries

    E-Print Network [OSTI]

    Knevitt, Gillian; Power, Chris; Bolton, James

    2014-01-01T23:59:59.000Z

    We investigate the influence of High Mass X-ray Binaries on their high redshift environments. Using a one-dimensional radiative transfer code, we predict the ionization and temperature profiles surrounding a coeval stellar population, composed of main sequence stars and HMXBs, at various times after its formation. We consider both uniform density surroundings, and a cluster embedded in a 10^8 solar mass NFW halo. HMXBs in a constant density environment produce negligible enhanced ionization because of their high-energy SEDs and short lifetimes. In this case, HMXBs only marginally contribute to the local heating rate. For NFW profiles, radiation from main sequence stars cannot prevent the initially ionized volume from recombining since it is unable to penetrate the high density galactic core. However, HMXB photons stall recombinations behind the front, keeping it partially ionized for longer. The increased electron density in these partially ionized regions promotes further cooling, resulting in lower IGM temp...

  1. 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

  2. Radiation detector

    DOE Patents [OSTI]

    Fultz, Brent T. (Berkeley, CA)

    1983-01-01T23:59:59.000Z

    Apparatus is provided for detecting radiation such as gamma rays and X-rays generated in backscatter Mossbauer effect spectroscopy and X-ray spectrometry, which has a large "window" for detecting radiation emanating over a wide solid angle from a specimen and which generates substantially the same output pulse height for monoenergetic radiation that passes through any portion of the detection chamber. The apparatus includes a substantially toroidal chamber with conductive walls forming a cathode, and a wire anode extending in a circle within the chamber with the anode lying closer to the inner side of the toroid which has the least diameter than to the outer side. The placement of the anode produces an electric field, in a region close to the anode, which has substantially the same gradient in all directions extending radially from the anode, so that the number of avalanche electrons generated by ionizing radiation is independent of the path of the radiation through the chamber.

  3. Radiation detector

    DOE Patents [OSTI]

    Fultz, B.T.

    1980-12-05T23:59:59.000Z

    Apparatus is provided for detecting radiation such as gamma rays and x-rays generated in backscatter Moessbauer effect spectroscopy and x-ray spectrometry, which has a large window for detecting radiation emanating over a wide solid angle from a specimen and which generates substantially the same output pulse height for monoenergetic radiation that passes through any portion of the detection chamber. The apparatus includes a substantially toroidal chamber with conductive walls forming a cathode, and a wire anode extending in a circle within the chamber with the anode lying closer to the inner side of the toroid which has the least diameter than to the outer side. The placement of the anode produces an electric field, in a region close to the anode, which has substantially the same gradient in all directions extending radially from the anode, so that the number of avalanche electrons generated by ionizing radiation is independent of the path of the radiation through the chamber.

  4. 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...

  5. 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...

  6. Survivable pulse power space radiator

    DOE Patents [OSTI]

    Mims, J.; Buden, D.; Williams, K.

    1988-03-11T23:59:59.000Z

    A thermal radiator system is described for use on an outer space vehicle, which must survive a long period of nonuse and then radiate large amounts of heat for a limited period of time. The radiator includes groups of radiator panels that are pivotally connected in tandem, so that they can be moved to deployed configuration wherein the panels lie largely coplanar, and to a stowed configuration wherein the panels lie in a stack to resist micrometerorite damage. The panels are mounted on a boom which separates a hot power source from a payload. While the panels are stowed, warm fluid passes through their arteries to keep them warm enough to maintain the coolant in a liquid state and avoid embrittlement of material. The panels can be stored in a largely cylindrical shell, with panels progressively further from the boom being of progressively shorter length. 5 figs.

  7. Decay heat removal by natural convection - the RVACS system.

    SciTech Connect (OSTI)

    Tzanos, C. P.

    1999-08-17T23:59:59.000Z

    In conclusion, this work shows that for sodium coolant the reactor vessel auxiliary cooling system (RVACS) is an effective passive heat removal system if the reactor power does not exceed about 1600 MW(th). Its effectiveness is limited by the effective radiative heat transfer coefficient in the inner gap. In a lead cooled system, economic considerations may impose a lower limit.

  8. The budgets of heat and salinity in NEMO M. Hieronymus

    E-Print Network [OSTI]

    Nycander, Jonas

    of the ocean is seen to be dominated by penetrative shortwave radiation, which is so influ- ential that we Keywords: Heat budget Salinity budget NEMO Isoneutral diffusion Shortwave penetration a b s t r a c in the Nucleus for European Modelling of the Ocean (NEMO) model. It is seen that the heat fluxes in NEMO

  9. 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.

  10. 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.

  11. 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...

  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. 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

  14. 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...

  15. A spatially resolved study of photoelectric heating and [CII] cooling in the LMC

    E-Print Network [OSTI]

    D. Rubin; S. Hony; S. C. Madden; A. G. G. M Tielens; M. Meixner; R. Indebetouw; W. Reach; A. Ginsburg; S. Kim; K. Mochizuki; B. Babler; M. Block; S. B Bracker; C. W. Engelbracht; B. -Q. For; K. Gordon; J. L. Hora; C. Leitherer; M. Meade; K. Misselt; M. Sewilo; U. Vijh; B. Whitney

    2008-12-12T23:59:59.000Z

    (abridged) We study photoelectric heating throughout the Large Magellanic Cloud. We quantify the importance of the [CII] cooling line and the photoelectric heating process of various environments in the LMC and investigate which parameters control the extent of photoelectric heating. We use the BICE [CII] map and the Spitzer/SAGE infrared maps. We examine the spatial variations in the efficiency of photoelectric heating: photoelectric heating rate over power absorbed by grains. We correlate the photoelectric heating efficiency and the emission from various dust constituents and study the variations as a function of H\\alpha emission, dust temperatures, and the total infrared luminosity. From this we estimate radiation field, gas temperature, and electron density. We find systematic variations in photoelectric efficiency. The highest efficiencies are found in the diffuse medium, while the lowest coincide with bright star-forming regions (~1.4 times lower). The [CII] line emission constitutes 1.32% of the far infrared luminosity across the whole of the LMC. We find correlations between the [CII] emission and ratios of the mid infrared and far infrared bands, which comprise various dust constituents. The correlations are interpreted in light of the spatial variations of the dust abundance and by the local environmental conditions that affect the dust emission properties. As a function of the total infrared surface brightness, S_{TIR}, the [CII] surface brightness can be described as: S_{[CII]}=1.25 S_{TIR}^{0.69} [10^{-3} erg s^{-1} cm^{-2} sr^{-1}]. The [CII] emission is well-correlation with the 8 micrometer emission, suggesting that the polycyclic aromatic hydrocarbons play a dominant role in the photoelectric heating process.

  16. Time encoded radiation imaging

    DOE Patents [OSTI]

    Marleau, Peter; Brubaker, Erik; Kiff, Scott

    2014-10-21T23:59:59.000Z

    The various technologies presented herein relate to detecting nuclear material at a large stand-off distance. An imaging system is presented which can detect nuclear material by utilizing time encoded imaging relating to maximum and minimum radiation particle counts rates. The imaging system is integrated with a data acquisition system that can utilize variations in photon pulse shape to discriminate between neutron and gamma-ray interactions. Modulation in the detected neutron count rates as a function of the angular orientation of the detector due to attenuation of neighboring detectors is utilized to reconstruct the neutron source distribution over 360 degrees around the imaging system. Neutrons (e.g., fast neutrons) and/or gamma-rays are incident upon scintillation material in the imager, the photons generated by the scintillation material are converted to electrical energy from which the respective neutrons/gamma rays can be determined and, accordingly, a direction to, and the location of, a radiation source identified.

  17. 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.

  18. 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...

  19. Galaxies that Shine: radiation-hydrodynamical simulations of disk galaxies

    E-Print Network [OSTI]

    Rosdahl, Joakim; Teyssier, Romain; Agertz, Oscar

    2015-01-01T23:59:59.000Z

    Radiation feedback is typically implemented using subgrid recipes in hydrodynamical simulations of galaxies. Very little work has so far been performed using radiation-hydrodynamics (RHD), and there is no consensus on the importance of radiation feedback in galaxy evolution. We present RHD simulations of isolated galaxy disks of different masses with a resolution of 18 pc. Besides accounting for supernova feedback, our simulations are the first galaxy-scale simulations to include RHD treatments of photo-ionisation heating and radiation pressure, from both direct optical/UV radiation and multi-scattered, re-processed infrared (IR) radiation. Photo-heating smooths and thickens the disks and suppresses star formation about as much as the inclusion of ("thermal dump") supernova feedback does. These effects decrease with galaxy mass and are mainly due to the prevention of the formation of dense clouds, as opposed to their destruction. Radiation pressure, whether from direct or IR radiation, has little effect, but ...

  20. 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...

  1. 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...

  2. Microscreen radiation shield for thermoelectric generator

    DOE Patents [OSTI]

    Hunt, Thomas K. (Ann Arbor, MI); Novak, Robert F. (Farmington Hills, MI); McBride, James R. (Ypsilanti, MI)

    1990-01-01T23:59:59.000Z

    The present invention provides a microscreen radiation shield which reduces radiative heat losses in thermoelectric generators such as sodium heat engines without reducing the efficiency of operation of such devices. The radiation shield is adapted to be interposed between a reaction zone and a means for condensing an alkali metal vapor in a thermoelectric generator for converting heat energy directly to electrical energy. The radiation shield acts to reflect infrared radiation emanating from the reaction zone back toward the reaction zone while permitting the passage of the alkali metal vapor to the condensing means. The radiation shield includes a woven wire mesh screen or a metal foil having a plurality of orifices formed therein. The orifices in the foil and the spacing between the wires in the mesh is such that radiant heat is reflected back toward the reaction zone in the interior of the generator, while the much smaller diameter alkali metal atoms such as sodium pass directly through the orifices or along the metal surfaces of the shield and through the orifices with little or no impedance.

  3. Modeling the comfort effects of short-wave solar radiation indoors

    E-Print Network [OSTI]

    Arens, Edward; Hoyt, Tyler; Zhou, Xin; Huang, Li; Zhang, Hui; Schiavon, Stefano

    2015-01-01T23:59:59.000Z

    2004. [3] Blum HF. Solar heat load, its relationship to theS, Parsons K. The effects of solar radiation on thermalParsons K. The effects of solar radiation and black body re-

  4. 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

  5. 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.

  6. Enhancing VHTR Passive Safety and Economy with Thermal Radiation Based Direct Reactor Auxiliary Cooling System

    SciTech Connect (OSTI)

    Haihua Zhao; Hongbin Zhang; Ling Zou; Xiaodong Sun

    2012-06-01T23:59:59.000Z

    One of the most important requirements for Gen. IV Very High Temperature Reactor (VHTR) is passive safety. Currently all the gas cooled version of VHTR designs use Reactor Vessel Auxiliary Cooling System (RVACS) for passive decay heat removal. The decay heat first is transferred to the core barrel by conduction and radiation, and then to the reactor vessel by thermal radiation and convection; finally the decay heat is transferred to natural circulated air or water systems. RVACS can be characterized as a surface based decay heat removal system. The RVACS is especially suitable for smaller power reactors since small systems have relatively larger surface area to volume ratio. However, RVACS limits the maximum achievable power level for modular VHTRs due to the mismatch between the reactor power (proportional to volume) and decay heat removal capability (proportional to surface area). When the relative decay heat removal capability decreases, the peak fuel temperature increases, even close to the design limit. Annular core designs with inner graphite reflector can mitigate this effect; therefore can further increase the reactor power. Another way to increase the reactor power is to increase power density. However, the reactor power is also limited by the decay heat removal capability. Besides the safety considerations, VHTRs also need to be economical in order to compete with other reactor concepts and other types of energy sources. The limit of decay heat removal capability set by using RVACS has affected the economy of VHTRs. A potential alternative solution is to use a volume-based passive decay heat removal system, called Direct Reactor Auxiliary Cooling Systems (DRACS), to remove or mitigate the limitation on decay heat removal capability. DRACS composes of natural circulation loops with two sets of heat exchangers, one on the reactor side and another on the environment side. For the reactor side, cooling pipes will be inserted into holes made in the outer or inner graphite reflector blocks. There will be gaps between these cooling pipes and their corresponding surrounding graphite surfaces. Graphite has an excellent heat conduction property. By taking advantage of this feature, we can have a volume-based method to remove decay heat. The scalability can be achieved, if needed, by employing more rows of cooling pipes to accommodate higher decay heat rates. Since heat can easily conduct through the graphite regions between the holes made for the cooling pipes, those cooling pipes located further away from the active core region can still be very effective in removing decay heat. By removing the limit on the decay heat removal capability due to the limited available surface area as in a RVACS, the reactor power and power density can be significantly increased, without losing the passive heat removal feature. This paper will introduce the concept of using DRACS to enhance VHTR passive safety and economics. Three design options will be discussed, depending on the cooling pipe locations. Analysis results from a lumped volume based model and CFD simulations will be presented.

  7. 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

  8. RADIATION SAFETY TRAINING MANUAL Radiation Safety Office

    E-Print Network [OSTI]

    Sibille, Etienne

    protection and the potential risks of ionizing radiation. Radiation Safety Office personnel provide.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 II. OVERVIEW OF REGULATIONS, PROTECTION STANDARDS, AND RADIATION SAFETY ORGANIZATION.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 V. BASIC RADIATION PROTECTION PRINCIPLES

  9. 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.

  10. 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.

  11. 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.

  12. Radiation Safety

    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's PossibleRadiation Protection Radiation Protection Regulations: The Federal Regulation

  13. 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

  14. 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.

  15. 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.

  16. 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...

  17. High-heat-flux removal by phase-change fluid and particulate flow

    SciTech Connect (OSTI)

    Gorbis, Z.R.; Raffray, A.R.; Abdou, M.A. (Univ. of California, Los Angeles (United States))

    1993-07-01T23:59:59.000Z

    A new concept based on particulate flow in which either or both the particulates and the fluid could undergo phase changes is proposed. The presence of particulates provides not only a mechanism for additional heat removal through phase change but also the potential for increasing the rate of heat transfer by enhancing convection through surface region/bulk [open quotes]mixing[close quotes], by enhancing radiation, particularly for high-temperature cases; and for the case of multiphase fluid, by enhancing the boiling process. One particularly interesting coolant system based on this concept is [open quotes]subcooled boiling water-ice particulate[close quotes] flow. A preliminary analysis of this coolant system is presented, the results of which indicate that such a coolant system is better applied for cooling of relatively small surface areas with high local heat fluxes, where a conventional cooling system would come short of providing the required heat removal at acceptable coolant pressure levels. 14 refs., 8 figs.

  18. Environmental radiation detection via thermoluminescence

    DOE Patents [OSTI]

    Miller, S.D.

    1993-03-23T23:59:59.000Z

    The method and apparatus of the present invention relate to cryogenically cooling a thermoluminescent material, exposing it to a low level of radiation (less than about 1 R) while it is at the cooled temperature, warming the thermoluminescent material to room temperature'' and counting the photons emitted during heating. Sufficient sensitivity is achieved without exposing the thermoluminescent material to ultraviolet light thereby simplifying the measurements.

  19. Environmental radiation detection via thermoluminescence

    DOE Patents [OSTI]

    Miller, Steven D. (Richland, WA)

    1993-01-01T23:59:59.000Z

    The method and apparatus of the present invention relate to cryogenically cooling a thermoluminescent material, exposing it to a low level of radiation (less than about 1 R) while it is at the cooled temperature, warming the thermoluminescent material to "room temperature", and counting the photons emitted during heating. Sufficient sensitivity is achieved without exposing the thermoluminescent material to ultraviolet light thereby simplifying the measurements.

  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. Quantum Optomechanical Heat Engine

    E-Print Network [OSTI]

    Keye Zhang; Francesco Bariani; Pierre Meystre

    2014-04-17T23:59:59.000Z

    We investigate theoretically a quantum optomechanical realization of a heat engine. In a generic optomechanical arrangement the optomechanical coupling between the cavity field and the oscillating end-mirror results in polariton normal mode excitations whose character depends on the pump detuning and the coupling strength. By varying that detuning it is possible to transform their character from phonon-like to photon-like, so that they are predominantly coupled to the thermal reservoir of phonons or photons, respectively. We exploit the fact that the effective temperatures of these two reservoirs are different to produce a Otto cycle along one of the polariton branches. We discuss the basic properties of the system in two different regimes: in the optical domain it is possible to extract work from the thermal energy of a mechanical resonator at finite temperature, while in the microwave range one can in principle exploit the cycle to extract work from the blackbody radiation background coupled to an ultra-cold atomic ensemble.

  3. IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS 1 Modeling of Terahertz Heating Effects in

    E-Print Network [OSTI]

    Ganesan, Sashikumaar

    experiments involving biological tissues. Index Terms--Far infrared, Terahertz Heating, Breast and BrainIEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS 1 Modeling of Terahertz Heating Effects in real tissues causes heating as with any other electromagnetic radiation propagation. A finite element

  4. HEAT TRANSFERS IN A DOUBLE SKIN ROOF VENTILATED BY NATURAL CONVECTION IN SUMMER TIME

    E-Print Network [OSTI]

    Boyer, Edmond

    1 HEAT TRANSFERS IN A DOUBLE SKIN ROOF VENTILATED BY NATURAL CONVECTION IN SUMMER TIME P. H and the sheet metal: This is ventilation by natural convection. The remaining conductive heat from the sheet or in tropical and arid countries. In this work, radiation, convection and conduction heat transfers

  5. The Cost of Heat Exchanger Fouling in the U. S. Industries

    E-Print Network [OSTI]

    Rebello, W. J.; Richlen, S. L.; Childs, F.

    and other industries. The 1982 U.S. sales of all industrial heat exchangers, excepting boilers and automotive radiators, was about 285,000 units amounting to about $1.6 billion. The total heat duty of all the heat exchangers in industrial operation...

  6. Optimal Regulation of Heating Systems with Metering Based on Dynamic Simulation

    E-Print Network [OSTI]

    Zhao, H.; Wang, P.; Zeng, G.; Tian, Y.

    2006-01-01T23:59:59.000Z

    The mathematical models of heat networks and heat users are established using the node method. The physical model of a typical room instead of a heat user is used; meanwhile the equation of radiator controlled by thermostat is put forward to compute...

  7. 11th International Conference of Radiation Research

    SciTech Connect (OSTI)

    NONE

    1999-07-18T23:59:59.000Z

    Topics discussed in the conference included the following: Radiation Physics, Radiation Chemistry and modelling--Radiation physics and dosimetry; Electron transfer in biological media; Radiation chemistry; Biophysical and biochemical modelling; Mechanisms of DNA damage; Assays of DNA damage; Energy deposition in micro volumes; Photo-effects; Special techniques and technologies; Oxidative damage. Molecular and cellular effects-- Photobiology; Cell cycle effects; DNA damage: Strand breaks; DNA damage: Bases; DNA damage Non-targeted; DNA damage: other; Chromosome aberrations: clonal; Chromosomal aberrations: non-clonal; Interactions: Heat/Radiation/Drugs; Biochemical effects; Protein expression; Gene induction; Co-operative effects; ``Bystander'' effects; Oxidative stress effects; Recovery from radiation damage. DNA damage and repair -- DNA repair genes; DNA repair deficient diseases; DNA repair enzymology; Epigenetic effects on repair; and Ataxia and ATM.

  8. 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...

  9. A heat-driven monochromatic light source

    SciTech Connect (OSTI)

    Stefani, F.; Lawless, J.L.

    1989-04-01T23:59:59.000Z

    This work investigates theoretically the efficiency with which heat may be converted into resonance radiation in a cesium thermionic diode. An analytical model of a thermionic converter is employed which combines the coupled effects of line radiation transport, excited-state kinetics, and plasma diffusion. Operating regimes are established for various degrees of optical density in the plasma. The results indicate that monochromatic radiation can be produced with efficiencies on the order of 30 percent provided there is an adequate voltage drop across the plasma. In this study, a drop of one volt was used since it can be maintained without any electrical power input to the device. It is found that high efficiencies come by virtue of the higher interelectrode distances which the solutions will accommodate, and that radiation can be generated efficiently, even with optically dense gases.

  10. 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...

  11. 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...

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. Methods for fabricating a micro heat barrier

    DOE Patents [OSTI]

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

    2004-01-06T23:59:59.000Z

    Methods for fabricating 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.

  17. 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

  18. 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

  19. 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.

  20. Radiation of a neutral polarizable particle moving uniformly through a thermal radiation field

    E-Print Network [OSTI]

    G. V. Dedkov; A. A. Kyasov

    2014-06-25T23:59:59.000Z

    We discuss the properties of thermal electromagnetic radiation produced by a neutral polarizable nanoparticle moving with an arbitrary relativistic velocity in a heated vacuum background with a fixed temperature. We show that the particle in its own rest frame acquires the radiation temperature of vacuum, multiplied by a velocity-dependent factor, and then emits thermal photons predominantly in the forward direction. The intensity of radiation proves to be much higher than for the particle at rest. For metal particles with high energy, the ratio of emitted and absorbed radiation power is proportional to the Lorentz-factor squared.