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1

Table A6. Approximate Heat Rates for Electricity, and Heat Content ...  

U.S. Energy Information Administration (EIA)

State energy information, detailed and overviews. Maps. ... Table A6. Approximate Heat Rates for Electricity, and Heat Content of Electricity, 1949-2011

2

Table A6. Approximate Heat Rates for Electricity, and Heat Content ...  

U.S. Energy Information Administration (EIA)

Total Fossil Fuels 6,7: ... 7 The fossil-fuels heat rate is used as the thermal conversion factor for ... approximate the quantity of fossil fuels replaced by these ...

3

AN EFFICIENT APPROXIMATION OF THE CORONAL HEATING RATE FOR USE IN GLOBAL SUN–HELIOSPHERE SIMULATIONS  

E-Print Network (OSTI)

The origins of the hot solar corona and the supersonically expanding solar wind are still the subject of debate. A key obstacle in the way of producing realistic simulations of the Sun–heliosphere system is the lack of a physically motivated way of specifying the coronal heating rate. Recent one-dimensional models have been found to reproduce many observed features of the solar wind by assuming the energy comes from Alfvén waves that are partially reflected, then dissipated by magnetohydrodynamic turbulence. However, the nonlocal physics of wave reflection has made it difficult to apply these processes to more sophisticated (three-dimensional) models. This paper presents a set of robust approximations to the solutions of the linear Alfvén wave reflection equations. A key ingredient of the turbulent heating rate is the ratio of inward-to-outward wave power, and the approximations developed here allow this to be written explicitly in terms of local plasma properties at any given location. The coronal heating also depends on the frequency spectrum of Alfvén waves in the open-field corona, which has not yet been measured directly. A modelbased assumption is used here for the spectrum, but the results of future measurements can be incorporated easily. The resulting expression for the coronal heating rate is self-contained, computationally efficient, and applicable directly to global models of the corona and heliosphere. This paper tests and validates the approximations by comparing the results to exact solutions of the wave transport equations in several cases relevant to the fast and slow solar wind. Key words: interplanetary medium – magnetohydrodynamics (MHD) – solar wind – Sun: corona – turbulence – waves Online-only material: tar file of source code 1.

Steven R. Cranmer

2010-01-01T23:59:59.000Z

4

Heat pipe transient response approximation.  

SciTech Connect

A simple and concise routine that approximates the response of an alkali metal heat pipe to changes in evaporator heat transfer rate is described. This analytically based routine is compared with data from a cylindrical heat pipe with a crescent-annular wick that undergoes gradual (quasi-steady) transitions through the viscous and condenser boundary heat transfer limits. The sonic heat transfer limit can also be incorporated into this routine for heat pipes with more closely coupled condensers. The advantages and obvious limitations of this approach are discussed. For reference, a source code listing for the approximation appears at the end of this paper.

Reid, R. S. (Robert Stowers)

2001-01-01T23:59:59.000Z

5

Heat Rate Program Guidelines  

Science Conference Proceedings (OSTI)

Power plant facilities with performance or heat rate improvement programs perform better than those that do not have those programs. A heat rate improvement program typically provides sufficient information for decision making with respect to timely maintenance actions and/or operational adjustments. Monitoring the performance of any power plant component includes the trending of parameters that also describe the performance of other plant components, providing insight and information on improving ...

2012-12-31T23:59:59.000Z

6

Heat flow in the postquasistatic approximation  

Science Conference Proceedings (OSTI)

We apply the postquasistatic approximation to study the evolution of spherically symmetric fluid distributions undergoing dissipation in the form of radial heat flow. For a model that corresponds to an incompressible fluid departing from the static equilibrium, it is not possible to go far from the initial state after the emission of a small amount of energy. Initially collapsing distributions of matter are not permitted. Emission of energy can be considered as a mechanism to avoid the collapse. If the distribution collapses initially and emits one hundredth of the initial mass only the outermost layers evolve. For a model that corresponds to a highly compressed Fermi gas, only the outermost shell can evolve with a shorter hydrodynamic time scale.

Rodriguez-Mueller, B. [Computational Science Research Center, College of Sciences, San Diego State University, San Diego, California (United States); Peralta, C. [Deutscher Wetterdienst, Frankfurter Strasse 135, 63067 Offenbach (Germany); School of Physics, University of Melbourne, Parkville, VIC 3010 (Australia); Barreto, W. [Centro de Fisica Fundamental, Facultad de Ciencias, Universidad de Los Andes, Merida (Venezuela, Bolivarian Republic of); Rosales, L. [Laboratorio de Fisica Computacional, Universidad Experimental Politecnica, 'Antonio Jose de Sucre', Puerto Ordaz (Venezuela, Bolivarian Republic of)

2010-08-15T23:59:59.000Z

7

Table A3. Approximate Heat Content of Petroleum Consumption and ...  

U.S. Energy Information Administration (EIA)

Table A3. Approximate Heat Content of Petroleum Consumption and Biofuels Production, 1949-2011 (Million Btu per Barrel)

8

Convergence Rates of Approximation by Translates  

E-Print Network (OSTI)

In this paper we consider the problem of approximating a function belonging to some funtion space Φ by a linear comination of n translates of a given function G. Ussing a lemma by Jones (1990) and Barron (1991) we show ...

Girosi, Federico

1992-03-01T23:59:59.000Z

9

2011 Heat Rate Improvement Conference  

Science Conference Proceedings (OSTI)

With the rising cost of fuel and the strong possibility of CO2 emissions regulations and limitations in the near future, utilities and power generation companies are focusing on power plant heat rate and performance. The Electric Power Research Institute (EPRI) 17th Heat Rate Improvement Conference is the latest in a series of meetings designed to assist attendees in addressing problems with power plant performance and in identifying cost-effective solutions for achieving and sustaining heat rate improve...

2011-03-28T23:59:59.000Z

10

Optimization Online - Approximate Primal Solutions and Rate ...  

E-Print Network (OSTI)

Mar 29, 2007... limit as the number of subgradient iterations increases to infinity). Furthermore, no convergence rate results are known for these algorithms.

11

Self-consistent microwave plasma heating rates  

SciTech Connect

Under conditions within a hot overdense plasma corona where the field frequency is much less than the electron plasma frequency and the field period is much less than the hydrodynamic expansion time it is shown that electron field reversal heating can exceed the combined classical heating rates due to inverse bremsstrahlung (skin effect) and field pressure (PdV) by a factor approximately v/ sub e//2v/sub i/ (half the ratio of electron and ion thermal velocities). In particular this rate can exceed the inertial expansion cooling rate at a collisionless corona density of approximately 1 percent solid core density and could be realized experimentally at core temperatures approximately 3--5 keV and microwave field intensities approximately 1 MG. (auth)

Ensley, D.L.; White, R.H.

1975-10-01T23:59:59.000Z

12

Table A3. Approximate Heat Content of Petroleum Consumption and ...  

U.S. Energy Information Administration (EIA)

U.S. Energy Information Administration / Annual Energy Review 2011 323 Table A3. Approximate Heat Content of Petroleum Consumption and Biofuels Production, Selected ...

13

Table A3. Approximate Heat Content of Petroleum Consumption and ...  

U.S. Energy Information Administration (EIA)

Table A3. Approximate Heat Content of Petroleum Consumption and Biofuels Production, 1949-2011 (Million Btu per Barrel) Year: Total Petroleum 1 ...

14

Solar Heating Rates: The Importance of Spherical Geometry  

Science Conference Proceedings (OSTI)

A crucial component of any GCM is a scheme for calculating atmospheric heating rates. Since a detailed treatment of all processes involved is time consuming, many approximations are usually made. An approximation used in virtually all GCM ...

D. J. Lary; M. Balluch

1993-12-01T23:59:59.000Z

15

ARM - Measurement - Radiative heating rate  

NLE Websites -- All DOE Office Websites (Extended Search)

govMeasurementsRadiative heating rate govMeasurementsRadiative heating rate ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Radiative heating rate The heating rate due to the divergence of long and shortwave radiative flux. Categories Radiometric, Atmospheric State Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. External Instruments MOLTS : Model Output Location Time Series Datastreams MOLTS : Model Output Location Time Series Datastreams MOLTSEDASSNDCLASS1 : Model Output Loc. Time Ser. (MOLTS): EDAS

16

Heat Rate Improvement Reference Manual  

Science Conference Proceedings (OSTI)

Performance optimization of fossil power plants is a high priority within the electric utilities in the new competitive environment. This manual can help utility engineers establish a heat rate improvement program.

1998-07-27T23:59:59.000Z

17

EPRI's Twelfth Heat Rate Improvement Conference Proceedings  

Science Conference Proceedings (OSTI)

The Twelfth Heat Rate Improvement Conference, sponsored by EPRI's Heat Rate and Cost Optimization Value Package, is the latest in a series of meetings designed to assist utilities in addressing problems with power plant performance and in identifying cost-effective solutions for achieving and maintaining heat rate improvement. The last conference was held in Baltimore in September 1998.

2001-01-22T23:59:59.000Z

18

2007 EPRI Heat Rate Improvement Conference Proceedings  

Science Conference Proceedings (OSTI)

Due to the rising cost of fuel and the growing possibility of carbon taxes in the not-too-distant future, utilities are once again focusing on the heat rate and performance of coal-fired power plants. The fifteenth Heat Rate Improvement Conference is the latest in this series of meetings designed to assist utilities in addressing problems with power plant performance and in identifying cost-effective solutions for achieving and maintaining heat rate improvement.

2007-03-30T23:59:59.000Z

19

Proceedings 2013 Heat Rate Improvement Conference  

Science Conference Proceedings (OSTI)

With the rising cost of fuel and the strong possibility of CO2 emissions regulations and limitations in the near future, utilities and power generation companies are focusing on power plant heat rate and performance. The 18th Heat Rate Improvement Conference is the latest in a series of meetings designed to assist attendees in addressing problems with power plant performance and identifying cost-effective solutions for achieving and sustaining heat rate ...

2013-04-05T23:59:59.000Z

20

Heating Rate Profiles in Galaxy Clusters  

E-Print Network (OSTI)

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.

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

2006-01-05T23:59:59.000Z

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Property:HeatRate | Open Energy Information  

Open Energy Info (EERE)

HeatRate HeatRate Jump to: navigation, search This is a property of type Number. Pages using the property "HeatRate" Showing 25 pages using this property. (previous 25) (next 25) A AES Mendota Biomass Facility + 17,873.6 + APS Biomass I Biomass Facility + 8,911 + Acme Landfill Biomass Facility + 12,916.67 + Adrian Energy Associates LLC Biomass Facility + 13,170.6 + Agrilectric Power Partners Ltd Biomass Facility + 17,327.1 + Al Turi Biomass Facility + 15,600.2 + Alabama Pine Pulp Biomass Facility + 15,826.23 + Albany Landfill Gas Utilization Project Biomass Facility + 11,913.9 + Altamont Gas Recovery Biomass Facility + 10,500 + American Canyon Power Plant Biomass Facility + 10,886.8 + American Ref-Fuel of Delaware Valley Biomass Facility + 18,674.9 +

22

Approximations for radiative cooling and heating in the solar chromosphere  

E-Print Network (OSTI)

Context. The radiative energy balance in the solar chromosphere is dominated by strong spectral lines that are formed out of LTE. It is computationally prohibitive to solve the full equations of radiative transfer and statistical equilibrium in 3D time dependent MHD simulations. Aims. To find simple recipes to compute the radiative energy balance in the dominant lines under solar chromospheric conditions. Methods. We use detailed calculations in time-dependent and 2D MHD snapshots to derive empirical formulae for the radiative cooling and heating. Results. The radiative cooling in neutral hydrogen lines and the Lyman continuum, the H and K and intrared triplet lines of singly ionized calcium and the h and k lines of singly ionized magnesium can be written as a product of an optically thin emission (dependent on temperature), an escape probability (dependent on column mass) and an ionization fraction (dependent on temperature). In the cool pockets of the chromosphere the same transitions contribute to the heat...

Carlsson, Mats

2012-01-01T23:59:59.000Z

23

Radiative Heating Rates for Saharan Dust  

Science Conference Proceedings (OSTI)

A combined longwave and shortwave radiative transfer model was used to determine effects of Saharan dust on the radiative fluxes and heating/cooling rates in the atmosphere. Cases are treated for cloud-free and overcast conditions over the ocean ...

Toby N. Carlson; Stanley G. Benjamin

1980-01-01T23:59:59.000Z

24

Design and demonstration of heat pipe cooling for NASP and evaluation of heating methods at high heating rates  

SciTech Connect

An evaluation of two heating methods for demonstration of NASP leading edge heat pipe technology was conducted. The heating methods were and rf induction heated plasma jet and direct rf induction. Tests were conducted to determine coupling from the argon plasma jet on a surface physically similar to a heat pipe. A molybdenum tipped calorimeter was fabricated and installed in an rf induction heated plasma jet for the test. The calorimetric measurements indicated a maximum power coupling of approximately 500 W/cm{sup 2} with the rf plasma jet. The effect of change in gas composition on the heating rate was investigated using helium. An alternative to the plasma heating of a heat pipe tip, an rf concentrator was evaluated for coupling to the hemispherical tip of a heat pipe. A refractory metal heat pipe was designed, fabricated, and tested for the evaluation. The heat pipe was designed for operation at 1400 to 1900 K with power input to 1000 W/cm{sup 2} over a hemispherical nose tip. Power input of 800 W/cm{sup 2} was demonstrated using the rf concentrator. 2 refs., 13 figs.

Merrigan, M.A.; Sena, J.T.

1989-01-01T23:59:59.000Z

25

High Heating Rate Thermal Desorption for Molecular Surface ...  

High Heating Rate Thermal Desorption for Molecular Surface Sampling Note: The technology described above is an early stage opportunity. Licensing ...

26

Rainfall and Radiative Heating Rates from TOGA COARE Atmospheric Budgets  

Science Conference Proceedings (OSTI)

Atmospheric heat and moisture budgets are used to determine rainfall and radiative heating rates over the western Pacific warm pool during the Tropical Ocean Global Atmosphere Coupled Ocean–Atmosphere Response Experiment (TOGA COARE). Results are ...

Richard H. Johnson; Paul E. Ciesielski

2000-05-01T23:59:59.000Z

27

Evaluation of Peak Heat Release Rates in Electrical Cabinet Fires  

Science Conference Proceedings (OSTI)

The purpose of this report is to reanalyze the peak heat release rates (HRRs) from fires occurring in electrical cabinets of nuclear power plants.

2012-02-23T23:59:59.000Z

28

Microbase Cloud Products and Associated Heating Rates in the...  

NLE Websites -- All DOE Office Websites (Extended Search)

Microbase Cloud Products and Associated Heating Rates in the Tropical Western Pacific J. H. Mather and S. A. McFarlane Pacific Northwest National Laboratory Richland, Washington...

29

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

NLE Websites -- All DOE Office Websites (Extended Search)

ProductsBroadband Heating Rate Profile Project ProductsBroadband Heating Rate Profile Project (BBHRP) Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : Broadband Heating Rate Profile Project (BBHRP) 2000.03.01 - 2006.02.28 Site(s) SGP General Description 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

30

Radiative Heating and Cooling Rates in the Middle Atmosphere  

Science Conference Proceedings (OSTI)

One of the limitations to the accurate calculation of radiative heating and cooling rates in the stratosphere and mesosphere has been the lack of accurate data on the atmospheric temperature and composition. Data from the LIMS experiment on ...

John C. Gille; Lawrence V. Lyjak

1986-10-01T23:59:59.000Z

31

Evaluation of Methodologies to Provide Comparative Heat Rates  

Science Conference Proceedings (OSTI)

Power generating companiesand even more so, their coal-fired facilitieshave struggled with the comparison of heat rate values from different periods of time. Comparing a unit's July heat rate to that recorded in January has been difficult because of several factors. First, the ambient temperatures are significantly different and manifest in operational and performance changes whose adjustments, although understood, contain uncertainty. The additional effects of variations in capacity and load following f...

2012-03-13T23:59:59.000Z

32

Evaluation of Fuel Quality Impacts on Heat Rate  

Science Conference Proceedings (OSTI)

The drive to leverage fuel switching to meet more stringent SO2 and NOX emissions requirements has led to both a reduction in power station efficiency and a poorer net plant heat rate (NPHR) in many cases. The root causes include higher fuel moisture content, lower fuel energy content, poorer combustion efficiency, increased station service, and decreased unit capability. This report demonstrates the sensitivity of the key metrics of power station efficiency and heat rate to coal quality parameters, vari...

2010-12-09T23:59:59.000Z

33

Turbine Cycle Heat Rate Monitoring: Technology and Application  

Science Conference Proceedings (OSTI)

Research has been completed on available technology for monitoring turbine cycle heat rate and factors affecting the successful deployment of this technology in fossil generating plants. Information has been gathered from interviews with experienced industry plant staff and vendors. Trends were noted and are described in this report. The report is recommended as guidance for power generation fleets and individual plants seeking to establish a successful program for heat rate reduction.

2006-12-20T23:59:59.000Z

34

Approximation of Ocean Heat Storage by Ocean–Atmosphere Energy Exchange: Implications for Seasonal Cycle Mixed Layer Ocean Formulations  

Science Conference Proceedings (OSTI)

The approximation of ocean heat storage by the net surface energy flux and the implications for zonal mean SST simulation using mixed layer ocean formulation are examined. The analysis considers both constant and variable depth mixed layers. ...

Robert G. Gallimore; David D. Houghton

1987-08-01T23:59:59.000Z

35

Coal plasticity at high heating rates and temperatures  

SciTech Connect

The broad objective of this project is to obtain improved, quantitative understanding of the transient plasticity of bituminous coals under high heating rates and other reaction and pretreatment conditions of scientific and practical interest. To these ends the research plan is to measure the softening and resolidification behavior of two US bituminous coals with a rapid-heating, fast response, high-temperature coal plastometer, previously developed in this laboratory. Specific measurements planned for the project include determinations of apparent viscosity, softening temperature, plastic period, and resolidificationtime for molten coal: (1) as a function of independent variations in coal type, heating rate, final temperature, gaseous atmosphere (inert, 0{sub 2} or H{sub 2}), and shear rate; and (2) in exploratory runs where coal is pretreated (preoxidation, pyridine extraction, metaplast cracking agents), before heating. The intra-coal inventory and molecular weight distribution of pyridine extractables will also be measured using a rapid quenching, electrical screen heater coal pyrolysis reactor. The yield of extractables is representative of the intra-coal inventory of plasticing agent (metaplast) remaining after quenching. Coal plasticity kinetics will then be mathematically modeled from metaplast generation and depletion rates, via a correlation between the viscosity of a suspension and the concentration of deformable medium (here metaplast) in that suspension. Work during this reporting period has been concerned with re-commissioning the rapid heating rate plastometer apparatus.

Darivakis, G.S.; Peters, W.A.; Howard, J.B.

1990-01-01T23:59:59.000Z

36

Status of the Broadband Heating Rate Profile (BBHRP) VAP  

NLE Websites -- All DOE Office Websites (Extended Search)

Status of the Broadband Heating Rate Profile (BBHRP) VAP Status of the Broadband Heating Rate Profile (BBHRP) VAP Mlawer, Eli Atmospheric & Environmental Research, Inc. Clough, Shepard Atmospheric and Environmental Research Delamere, Jennifer Atmospheric and Environmental Research, Inc. Miller, Mark Brookhaven National Laboratory Johnson, Karen Brookhaven National Laboratory Troyan, David Brookhaven National Laboratory Jensen, Michael Brookhaven National Laboratory Shippert, Timothy Pacific Northwest National Laboratory Long, Chuck Pacific Northwest National Laboratory Flynn, Connor Pacific Northwest National Laboratory Sivaraman, Chitra Pacific Northwest National Laboratory Turner, David University of Wisconsin-Madison Heck, Patrick University of Wisconsin Rutan, David Analytical Services & Materials, Inc.

37

Retrofits for Improved Heat Rate and Availability: Circulating Water Heat Recovery Retrofits  

Science Conference Proceedings (OSTI)

Circulating water heat recovery is a means of directly increasing the thermal efficiency of a power plant. If only fuel savings are considered, the economic benefit is often only marginal. However, when increased megawatt output and heat-rate improvements are included in the economic analysis, such retrofits can be attractive, with break-even fuel costs sometimes approaching $1/million Btu.

1990-11-20T23:59:59.000Z

38

Demonstration of EPRI Heat Rate Guidelines at Southern California Edison Ormond Beach Unit 2  

Science Conference Proceedings (OSTI)

Using EPRI's heat rate improvement guidelines, Southern California Edison Company (SCE) developed a heat rate improvement program and realized significant fuel cost reduction. Other utilities can follow SCE's example to develop their own effective heat rate improvement programs.

1992-10-01T23:59:59.000Z

39

Sensitivity of Radiative Fluxes and Heating Rates to Cloud Microphysics  

NLE Websites -- All DOE Office Websites (Extended Search)

Sensitivity of Radiative Fluxes and Heating Sensitivity of Radiative Fluxes and Heating Rates to Cloud Microphysics S. F. Iacobellis and R. C. J. Somerville Scripps Institution of Oceanography University of California, San Diego La Jolla, California G. M. McFarquhar University of Illinois at Urbana-Champaign Urbana, Illinois D. L. Mitchell Desert Research Institute Reno, Nevada Introduction A single-column model (SCM) is used to examine the sensitivity of basic quantities such as atmospheric radiative heating rates and surface and top of atmosphere (TOA) radiative fluxes to various parameter- izations of clouds and cloud microphysics. The SCM was run at the Atmospheric Radiation Measurement (ARM) Program's Southern Great Plains (SGP), Tropical Western Pacific (TWP), and North Slope of Alaska (NSA) sites using forcing data derived from forecast products. The forecast

40

Rate of Change of Heat Storage of the World Ocean  

Science Conference Proceedings (OSTI)

Results or a Fourier analysis of climatological fields of the monthly rate of change of heat storage for the world ocean are presented. The amplitude and Phase of the first harmonic are shown, as well as the percent variance of the annual cycle ...

Sydney Levitus

1987-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Survey of Impacts of Environmental Controls on Plant Heat Rate  

Science Conference Proceedings (OSTI)

Environmental controls for sulfur and nitrogen oxides, particulates, mercury, and other pollutants reduce the efficiency of power plants. This report documents the impacts of state-of-the-art environmental controls on power plant heat rate and identifies ways these impacts may be reduced through operating and design changes.

2009-12-07T23:59:59.000Z

42

Property:Heat Recovery Rating | Open Energy Information  

Open Energy Info (EERE)

Rating Rating Jump to: navigation, search This is a property of type Number. Pages using the property "Heat Recovery Rating" Showing 22 pages using this property. D Distributed Generation Study/10 West 66th Street Corp + 300,000 + Distributed Generation Study/615 kW Waukesha Packaged System + 2,500,000 + Distributed Generation Study/Aisin Seiki G60 at Hooligans Bar and Grille + 46,105 + Distributed Generation Study/Arrow Linen + 3,000,000 + Distributed Generation Study/Dakota Station (Minnegasco) + 290,000 + Distributed Generation Study/Elgin Community College + 11,200,000 + Distributed Generation Study/Emerling Farm + 2,000,000 + Distributed Generation Study/Floyd Bennett + 230,000 + Distributed Generation Study/Harbec Plastics + 3,750,000 + Distributed Generation Study/Hudson Valley Community College + 32,500,000 +

43

forth through the heat exchangers, thereby phasing the rates at which heat is absorbed and rejected from  

E-Print Network (OSTI)

#12;forth through the heat exchangers, thereby phasing the rates at which heat is absorbed balance as shown in Fig. 3 still indi- cated a greater heat loss to the engine coolant than predicted. This was caused by excessive heat leak- age from the hot to the cold working spaces, primarily by the flow leakage

Oak Ridge National Laboratory

44

The Influence of Different Inflow Water Rate and Temperature on Heat Exchange Performance of Underground Heat Pump  

Science Conference Proceedings (OSTI)

in the paper, the influence of different inflow water rate and temperature on heat exchange performance of underground heat pump were discussed by experiment, two vital parameters was defined to measure the properties of ground heat exchanger: Energy ... Keywords: heat pump, underground tube, influential factors, parameters

Zheng Min; Li Bai-yi

2011-11-01T23:59:59.000Z

45

Assessment of Hydrometeor Collection Rates from Exact and Approximate Equations. Part II: Numerical Bounding  

Science Conference Proceedings (OSTI)

Past microphysical investigations, including Part I of this study, have noted that the collection equation, when applied to the interaction between different hydrometeor species, can predict large mass transfer rates, even when an exact solution ...

Brian J. Gaudet; Jerome M. Schmidt

2007-01-01T23:59:59.000Z

46

PERFORMANCE OF A SINGLE-ROW HEAT EXCHANGER AT LOW IN-TUBE FLOW RATES  

E-Print Network (OSTI)

PERFORMANCE OF A SINGLE-ROW HEAT EXCHANGER AT LOW IN-TUBE FLOW RATES A Thesis Submitted April 1995 #12;PERFORMANCE OF A SINGLE-ROW HEAT EXCHANGER AT LOW IN-TUBE FLOW RATES by Xiangwei Zhao Abstract The steady and time-dependentbehavior of a single-row heat exchanger with water and air in the in

Sen, Mihir

47

Evaluation of Methodologies for Real-Time Incremental Heat Rate Determination  

Science Conference Proceedings (OSTI)

Reduced staffing, tighter budgets, ISOs, and increased competition have created the need for maintaining up-to-date incremental heat rate information. Combining recent advances in analytics with modern performance monitoring packages and data historians may provide the capability for closer-to-real-time incremental heat rate determination. Many power generating companies either rely on historic data or slow and labor intensive testing to establish incremental heat rate curves. Those curves are ...

2013-11-26T23:59:59.000Z

48

EFFECT OF HEATING RATE ON THE THERMODYNAMIC PROPERTIES OF PULVERIZED COAL  

SciTech Connect

This final technical report describes work performed under DOE Grant No. DE-FG22-96PC96224 during the period September 24, 1996 to September 23, 1999 which covers the entire performance period of the project. During this period, modification, alignment, and calibration of the measurement system, measurement of devolatilization time-scales for single coal particles subjected to a range of heating rates and temperature data at these time-scales, and analysis of the temperature data to understand the effect of heating rates on coal thermal properties were carried out. A new thermodynamic model was developed to predict the heat transfer behavior for single coal particles using one approach based on the analogy for thermal property of polymers. Results of this model suggest that bituminous coal particles behave like polymers during rapid heating on the order of 10{sup 4}-10{sup 5} K/s. At these heating rates during the early stages of heating, the vibrational part of the heat capacity of the coal molecules appears to be still frozen but during the transition from heat-up to devolatilization, the heat capacity appears to attain a sudden jump in its value as in the case of polymers. There are a few data available in the coal literature for low heating rate experiments (10{sup 2}-10{sup 3} K/s) conducted by UTRC, our industrial partner, in this project. These data were obtained for a longer heating duration on the order of several seconds as opposed to the 10 milliseconds heating time of the single particle experiments discussed above. The polymer analogy model was modified to include longer heating time on the order of several seconds to test these data. However, the model failed to predict these low heating rate data. It should be noted that UTRC's work showed reasonably good agreement with Merrick model heat capacity predictions at these low heating rates, but at higher heating rates UTRC observed that coal thermal response was heat flux dependent. It is concluded that at combustion level heating rates (10{sup 4}-10{sup 5} K/s) coal structural changes are delayed and attendant increases in heat capacity and thermal conductivity are pushed to higher temperatures or require significant hold times to become manifest.

Ramanathan Sampath

2000-01-01T23:59:59.000Z

49

An analysis of lower-dimensional approximations to the scalar dissipation rate using direct numerical simulations of plane jet flames  

SciTech Connect

The difficulty of experimental measurements of the scalar dissipation rate in turbulent flames has required researchers to estimate the true three-dimensional (3D) scalar dissipation rate from one-dimensional (1D) or two-dimensional (2D) gradient measurements. In doing so, some relationship must be assumed between the true values and their lower dimensional approximations. We develop these relationships by assuming a form for the statistics of the gradient vector orientation, which enables several new results to be obtained and the true 3D scalar dissipation PDF to be reconstructed from the lower-dimensional approximations. We use direct numerical simulations (DNS) of turbulent plane jet flames to examine the orientation statistics, and verify our assumptions and final results. We develop and validate new theoretical relationships between the lower-dimensional and true moments of the scalar dissipation PDF assuming a log-normal true PDF. We compare PDFs reconstructed from lower-dimensional gradient projections with the true values and find an excellent agreement for a 2D simulated measurement and also for a 1D simulated measurement perpendicular to the mean flow variations. Comparisons of PDFs of thermal dissipation from DNS with those obtained via reconstruction from 2D experimental measurements show a very close match, indicating this PDF is not unique to a particular flame configuration. We develop a technique to reconstruct the joint PDF of the scalar dissipation and any other scalar, such as chemical species or temperature. Reconstructed conditional means of the hydroxyl mass fraction are compared with the true values and an excellent agreement is obtained.

Chen, Jackie [Sandia National Laboratories (SNL); Sankaran, Ramanan [ORNL; Hawkes, Evatt R [Sandia National Laboratories (SNL)

2009-05-01T23:59:59.000Z

50

Relationship between the shear viscosity and heating rate in metallic glasses below the glass transition  

Science Conference Proceedings (OSTI)

It has been shown that first-order irreversible structural relaxation with distributed activation energies must lead to a linear decrease of the logarithm of Newtonian shear viscosity with the logarithm of heating rate upon linear heating of glass. Such a behavior is indeed observed in the experiments on metallic glasses. Structural relaxation-induced viscous flow leads to infra-low-frequency Maxwell viscoelastic internal friction, which is predicted to increase with the heating rate.

Khonik, Vitaly A.; Kobelev, N. P. [Department of General Physics, State Pedagogical University, Lenin Street 86, 394043 Voronezh (Russian Federation); Institute for Solid State Physics, Chernogolovka, 142432 Moscow District (Russian Federation)

2008-04-01T23:59:59.000Z

51

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

NLE Websites -- All DOE Office Websites (Extended Search)

ProductsCloud Properties and Radiative Heating Rates for ProductsCloud Properties and Radiative Heating Rates for TWP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Cloud Properties and Radiative Heating Rates for TWP 2002.01.01 - 2012.02.08 Site(s) TWP General Description 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

52

Dependency of Heat Transfer Rate on the Brinkman Number in Microchannels  

E-Print Network (OSTI)

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.

H. S. Park

2008-01-07T23:59:59.000Z

53

EFFECT OF HEATING RATE ON THE THERMODYNAMIC PROPERTIES OF PULVERIZED COAL  

Science Conference Proceedings (OSTI)

This semi-annual technical progress report describes work performed under DOE Grant No. DE-FG22-96PC96224 during the period March 24, 1999 to September 23, 1999 which covers the last (sixth) six months of the project. During this reporting period, extraction of devolatilization time-scales and temperature data at these time-scales analyzing the high-speed films taken during the experiments was complete. Also a new thermodynamic model was developed to predict the heat transfer behavior for coal particles subjected to a range of heating rates using one approach based on the analogy of polymers. Sensitivity analyses of this model suggest that bituminous coal particles behave like polymers during rapid heating on the order of 10{sup 4}-10{sup 7} K/s. At these heating rates during the early stages within the first few milliseconds of heating time, the vibrational part of the heat capacity of the coal molecules appears to be still frozen but during the transition from heat-up to devolatization, the heat capacity appears to attain a sudden jump in its value as in the case of polymers. There are few data available in the coal literature for 10{sup 2}-10{sup 3} K/s obtained by UTRC in their previous studies. These data were obtained for a longer heating duration on the order of several seconds as opposed to the 10 milliseconds heating time in the single particle experiments discussed above. The polymer analogy model is being modified to include longer heating time on the order of several seconds to test these data. It is expected that the model might still do a good job in the case of these larger heating time but very low heating rate experiments. Completion of the numerical analysis of the experimental data and preparation of the final report are in progress.

Ramanathan Sampath

1999-11-02T23:59:59.000Z

54

On the Effects of Cumulus Dimensions on Longwave Irradiance and Heating Rate Calculations  

Science Conference Proceedings (OSTI)

A model of a cumulus cloud field, parameterized as right circular cylinders, has been used to estimate the uncertainties in longwave radiation calculations of irradiances and heating rates caused by neglecting the dimensions of the clouds. The ...

Robert G. Ellingson

1982-04-01T23:59:59.000Z

55

The Impact of Polar Stratospheric Clouds on the Heating Rates of the Winter Polar Stratosphere  

Science Conference Proceedings (OSTI)

We have computed the perturbation to the infrared radiative heating rates of the lower stratosphere due to the occurrence of polar stratospheric clouds (PSCs) during the winter season in the Antarctic and Arctic regions. The calculations were ...

James B. Pollack; Christopher P. McKay

1985-02-01T23:59:59.000Z

56

Calculating Monthly Radiative Fluxes and Heating Rates fromMonthly Cloud Observations  

Science Conference Proceedings (OSTI)

The radiative transfer model from NCAR’s general circulation model CCM3 is modified to calculate monthly radiative fluxes and heating rates from monthly observations of cloud properties from the International Satellite Cloud Climatology Project ...

John W. Bergman; Harry H. Hendon

1998-12-01T23:59:59.000Z

57

An Efficient Method for Online Calculations of Photolysis and Heating Rates  

Science Conference Proceedings (OSTI)

The authors present a computationally highly efficient method for the online calculation of photolysis and heating rates, which is especially suited for coupled transport–chemistry models. For this purpose, the spectral range 178.6 nm ? ? ? 752.5 ...

J. Landgraf; P. J. Crutzen

1998-03-01T23:59:59.000Z

58

Methods to Mitigate the Effect of Increased Cycling and Load Following on Heat Rate  

Science Conference Proceedings (OSTI)

Most of the U.S. coal-fired plants currently in service were designed for baseload operation. Today, however, actual generation conditions dictate that many of these units operate in a continuous transient mode, following generation demand. As such, they often experience large load changes throughout the day that result in a poorer plant heat rate. Reducing the throttle pressure, also known as sliding pressure, reduces throttling losses and is a potential method to reduce the heat rate penalties ...

2012-12-14T23:59:59.000Z

59

Model of home heating and calculation of rates of return to household energy conservation investment  

Science Conference Proceedings (OSTI)

This study attempts to find out if households' investments on energy conservation yield expected returns. It first builds a home-heating regression model, then uses the results of the model to calculate the rates of return for households' investments on the energy conservation. The home heating model includes housing characteristics, economic and demographic variables, appliance related variables, and regional dummy variables. Housing characteristic variables are modeled according to the specific physical relationship between the house and its heating requirement. Data from the Residential Energy Consumption Survey (RECS) of 1980-1981 is used for the empirical testing of the model. The model is estimated for single-detached family houses separately for three major home-heating fuel types: electricity, natural gas and fuel oil. Four scenarios are used to calculate rates of return for each household. The results show in the Northern areas the rates of return in most of the cases are a lot higher than market interest rates. In the Western and Southern areas, with few exceptions, the rates of return are lower than market interest rates. The variation of heating degree days and energy prices can affect the rates of return up to 20 percentage points.

Hsueh, L.M.

1984-01-01T23:59:59.000Z

60

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

Science Conference Proceedings (OSTI)

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.

Reedy, Wayne R. [Sentech, Inc.

2010-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Tropical Precipitation Rates during SOP-1, FGGE, Estimated from Heat and Moisture Budgets  

Science Conference Proceedings (OSTI)

This study presents global estimates of precipitation rates from 30°N to 30°S, derived from the “apparent” heat source (Q1) and “apparent” moisture sink (Q2) budgets using the NASA Goddard Laboratory for Atmospheres Level III-b analyses collected ...

Catherine B. Pedigo; Dayton G. Vincent

1990-03-01T23:59:59.000Z

62

Scale Dependence of Solar Heating Rates in Convective Cloud Systems with Implications to General Circulation Models  

Science Conference Proceedings (OSTI)

The authors examine 3D solar radiative heating rates within tropical convective–cirrus systems to identify the scales that contribute significantly to the spatial average over a climate model’s grid cell (i.e., its grid mean), and determine their ...

A. M. Vogelmann; V. Ramanathan; I. A. Podgorny

2001-04-01T23:59:59.000Z

63

Parametric Analysis of a 6500-Btu/kWh Heat Rate Dispersed Generator  

Science Conference Proceedings (OSTI)

Cost and performance assessments of two alternative system designs for a 2-MW molten carbonate fuel cell power plant yielded encouraging results: a 6500-Btu/kWh heat rate and a total plant investment of $1200-$1300/kW. Differences between the two designs establish a permissible range of operating conditions for the fuel cell that will help guide its development.

1985-08-14T23:59:59.000Z

64

EFFECT OF HEATING RATE ON THE THERMODYNAMIC PROPERTIES OF PULVERIZED COAL  

SciTech Connect

This semi-annual technical progress report describes work performed under DOE Grant No. DE-FG22-96PC96224 during the period September 24, 1998 to March 23, 1999 which covers the fifth six months of the project. Devolatilization is an important initial step in virtually all commercial fossil fuel applications such as combustion, gasification, and liquefaction. Characterization of the temperature history of pulverized coal particles under high heating rates, representative of coal combustors, is critical to the understanding of devolatilization. During this reporting period, characterization experiments were continued from the previous reporting period and completed to a total of 28 single coal particles. These particles were caught in the electrodynamic balance and their volume, external surface area, mass, and density were measured. The same single particles were then heated bidirectionally with a pulsed (10 ms pulse width) Nd:YAG laser beams of equal intensity with heating rates (10{sup 4} - 10{sup 7} K/s) representative of coal combustors. The temporal power variation in the laser pulse was monitored for use in the heat transfer analysis by an ultra-fast fiber optic uv light transmitter included in the beam path and coupled to a silicon photodiode. Transient surface temperatures of the particles were measured using a single-color pyrometer. Dynamics of volatile evolution and particle swelling were recorded using well established time-resolved high-speed cinematography. Presently, extraction of devolatilization time-scales and temperature data at these time-scales running the high-speed films taken during the experiments employing a 16mm movie projector are in progress. Heat transfer analyses for the devolatilization time-scales, and temperature measurements (and hence an understanding of the effect of heating rates on coal thermal properties) are also in progress. Shipment of the donated heated grid system components from our industrial partner, United Technologies Research Center (UTRC), CT to CAU was complete during the previous reporting period. Testing of the heated grid system components at CAU and sensitivity analyses of the heated grid heat transfer calculations are also in progress.

Ramanathan Sampath

1999-04-29T23:59:59.000Z

65

EFFECT OF HEATING RATE ON THE THERMODYNAMIC PROPERTIES OF PULVERIZED COAL  

SciTech Connect

This semi-annual technical progress report describes work performed under DOE Grant No. DE-FG22-96PC96224 during the period March 24, 1998 to September 23, 1998 which covers the fourth six months of the project. Existing laser heating set-up at the Single Particle Laboratory, Federal Energy Technology Center, Morgantown, WV would work only in the range of 10 to 10 4 5 K/s. During this reporting period, appropriate changes were made to the laser heating system to heat particles in the range of 10 to 10 K/s. Also, calibration for all the components of the 4 7 electrodynamic balance measurement system including single-color pyrometer and heating laser was successfully completed. Following the calibration, a large number of single coal particles were caught in the electrodynamic balance and their volume, external surface area, mass, and density were measured. The same single particles were then heated bidirectionally with a pulsed (10 ms pulse width) Nd:YAG laser beams of equal intensity. The temporal power variation in the laser pulse was monitored for use in the heat transfer analysis by an ultra-fast fiber optic uv light transmitter included in the beam path and coupled to a silicon photodiode. Measurements of changes in particle size that accompanied rapid heating was made by means of the high-speed diode array imaging system discussed in our previous reports. Dynamics of volatile evolution and particle swelling were recorded using well established time-resolved high-speed cinematography. Measurements of the radiant emissive power from the heated and cooled (when the laser is turned off) particles was made using the single-color pyrometer. The above experiments are being repeated for a significant number of coal particles for a number of heating rates in between 10 - 10 K/s at FETC, Morgantown. 4 7 Shipment of the donated heated grid system components from our industrial partner, United Technologies Research Center (UTRC), CT to CAU was complete during this reporting period. Testing of the heated grid system components at CAU is also in progress.

RAMANATHAN SAMPATH

1998-10-27T23:59:59.000Z

66

Electric field noise above surfaces: a model for heating rate scaling law in ion traps  

E-Print Network (OSTI)

We present a model for the scaling laws of the electric field noise spectral density as a function of the distance, $d$, above a conducting surface. Our analytical approach models the patch potentials by introducing a correlation length, $\\zeta$, of the electric potential on the surface. The predicted scaling laws are in excellent agreement with two different classes of experiments (cold trapped ions and cantilevers), that span at least four orders of magnitude of $d$. According to this model, heating rate in miniature ion traps could be greatly reduced by proper material engineering.

Dubessy, Romain; Guidoni, Luca

2008-01-01T23:59:59.000Z

67

Electric field noise above surfaces: a model for heating rate scaling law in ion traps  

E-Print Network (OSTI)

We present a model for the scaling laws of the electric field noise spectral density as a function of the distance, $d$, above a conducting surface. Our analytical approach models the patch potentials by introducing a correlation length, $\\zeta$, of the electric potential on the surface. The predicted scaling laws are in excellent agreement with two different classes of experiments (cold trapped ions and cantilevers), that span at least four orders of magnitude of $d$. According to this model, heating rate in miniature ion traps could be greatly reduced by proper material engineering.

Romain Dubessy; Thomas Coudreau; Luca Guidoni

2008-12-17T23:59:59.000Z

68

Sensitivity of shortwave radiative flux density, forcing, and heating rates to the aerosol vertical profile  

SciTech Connect

The effect of the aerosol vertical distribution on the solar radiation profiles, for idealized and measured profiles of optical properties (extinction and single-scattering albedo (SSA)) during the May 2003 Atmospheric Radiation Measurement (ARM) Aerosol Intensive Observation Period (AIOP), has been investigated using the Rapid Radiative Transfer Model Shortwave (RRTM_SW) code. Calculated profiles of down-welling and up-welling solar fluxes during the AIOP have been compared with the data measured by up- and down-looking solar broadband radiometers aboard a profiling research aircraft. The measured profiles of aerosol extinction, SSA, and water vapor obtained from the same aircraft that carried the radiometers served as the inputs for the model calculations. It is noteworthy that for this study, the uplooking radiometers were mounted on a stabilized platform that kept the radiometers parallel with respect to the earth’s horizontal plane. The results indicate that the shape of the aerosol extinction profiles has very little impact on direct radiative forcings at the top of atmosphere and surface in a cloud-free sky. However, as long as the aerosol is not purely scattering, the shape of the extinction profiles is important for forcing profiles. Identical extinction profiles with different absorption profiles drastically influence the forcing and heating rate profiles. Using aircraft data from 19 AIOP profiles over the Southern Great Plains (SGP), we are able to achieve broadband down-welling solar flux closure within 0.8% (bias difference) or 1.8% (rms difference), well within the expected measurement uncertainty of 1 to 3%. The poorer agreement in up-welling flux (bias -3.7%, rms 10%) is attributed to the use of inaccurate surface albedo data. The sensitivity tests reveal the important role accurate, vertically resolved aerosol extinction data plays in tightening flux closure. This study also suggests that in the presence of a strongly absorbing substance, aircraft flux measurements from a stabilized platform have the potential to determine heating rate profiles. These measurement-based heating rate profiles provide useful data for heating rate closure studies and indirect estimates of single scattering albedo assumed in radiative transfer calculations.

Guan, Hong; Schmid, Beat; Bucholtz, Anthony; Bergstrom, Robert

2010-03-31T23:59:59.000Z

69

Comments on the use of boiler efficiencies to determine unit heat rate  

SciTech Connect

The expression for boiler efficiency defined in ASME PTC4.1 was developed for evaluating boiler performance, carrying out acceptance tests on boilers and computing the effects of changes in parameters such as fuel characteristics on boiler performance. While satisfactory for applications such as these, this particular definition of boiler efficiency can result in substantial errors when used for computing unit performance. Sample calculations are presented for a 600 MW coal fired unit which show errors in net unit heat rate of 1 to 3 percent due to inconsistent definitions for boiler efficiency.

Levy, E.K.; Sarunac, N. (Lehigh Univ., Bethlehem, PA (USA). Energy Research Center); Leyse, R. (Electric Power Research Inst., Palo Alto, CA (USA))

1990-01-01T23:59:59.000Z

70

Nuclear mass inventory, photon dose rate and thermal decay heat of spent research reactor fuel assemblies  

SciTech Connect

This document has been prepared to assist research reactor operators possessing spent fuel containing enriched uranium of United States origin to prepare part of the documentation necessary to ship this fuel to the United States. Data are included on the nuclear mass inventory, photon dose rate, and thermal decay heat of spent research reactor fuel assemblies. Isotopic masses of U, Np, Pu and Am that are present in spent research reactor fuel are estimated for MTR, TRIGA and DIDO-type fuel assembly types. The isotopic masses of each fuel assembly type are given as functions of U-235 burnup in the spent fuel, and of initial U-235 enrichment and U-235 mass in the fuel assembly. Photon dose rates of spent MTR, TRIGA and DIDO-type fuel assemblies are estimated for fuel assemblies with up to 80% U-235 burnup and specific power densities between 0.089 and 2.857 MW/kg[sup 235]U, and for fission product decay times of up to 20 years. Thermal decay heat loads are estimated for spent fuel based upon the fuel assembly irradiation history (average assembly power vs. elapsed time) and the spent fuel cooling time.

Pond, R.B.; Matos, J.E.

1996-12-31T23:59:59.000Z

71

On-Line Heat Rate Monitor Assessment, Part 2: Results of the Demonstration and Application of Exergetic Systems' Calculational Engine  

Science Conference Proceedings (OSTI)

This report summarizes EPRI demonstrations of Exergetic Systems' Calculational Engine, an on-line heat rate monitor, at two pulverized-coal-fired plants. It also summarizes results from independent installations and tests of the Calculational Engine.

2004-12-27T23:59:59.000Z

72

Latent Heating and Cooling Rates in Developing and Nondeveloping Tropical Disturbances during TCS-08: TRMM PR versus ELDORA Retrievals  

Science Conference Proceedings (OSTI)

Unique sets of Electra Doppler Radar (ELDORA) observations in both developing and nondeveloping tropical disturbances in the western North Pacific are used to retrieve latent heating and cooling rates. During the reintensification of Sinlaku, ...

Myung-Sook Park; Russell L. Elsberry

2013-01-01T23:59:59.000Z

73

Latent Heating and Cooling Rates in Developing and Nondeveloping Tropical Disturbances during TCS-08: Radar-Equivalent Retrievals from Mesoscale Numerical Models and ELDORA  

Science Conference Proceedings (OSTI)

Latent heating and cooling rates have a critical role in predicting tropical cyclone formation and intensification. In a prior study, Park and Elsberry estimated the latent heating and cooling rates from aircraft Doppler radar [Electra Doppler ...

Myung-Sook Park; Andrew B. Penny; Russell L. Elsberry; Brian J. Billings; James D. Doyle

2013-01-01T23:59:59.000Z

74

Influence of Mean Zonal Motion and Meridional Temperature Gradients on the Solar Semidiurnal Atmospheric Tide: A Revised Spectral Study with Improved Heating Rates  

Science Conference Proceedings (OSTI)

Calculations of the semidiurnal atmospheric tide at solstice using improved heating rates are presented. The heating rates for solar absorption by water vapor are based on a global water vapor distribution (Jenne, 1969, 1975; Jenne et al., 1974), ...

R. L. Walterscheid; J. G. DeVore; S. V. Venkateswaran

1980-02-01T23:59:59.000Z

75

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

NLE Websites -- All DOE Office Websites (Extended Search)

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

76

Expert Meeting Report: Exploring the Disconnect Between Rated and Field Performance of Water Heating Systems  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exploring the Disconnect Exploring the Disconnect Between Rated and Field Performance of Water Heating Systems M. Hoeschele and E. Weitzel Alliance for Residential Building Innovation (ARBI) May 2013 NOTICE This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, subcontractors, or affiliated partners makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark,

77

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

Science Conference Proceedings (OSTI)

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.

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

2006-01-31T23:59:59.000Z

78

Coal plasticity at high heating rates and temperatures. First technical progress report for the fourth quarter 1989  

SciTech Connect

The broad objective of this project is to obtain improved, quantitative understanding of the transient plasticity of bituminous coals under high heating rates and other reaction and pretreatment conditions of scientific and practical interest. To these ends the research plan is to measure the softening and resolidification behavior of two US bituminous coals with a rapid-heating, fast response, high-temperature coal plastometer, previously developed in this laboratory. Specific measurements planned for the project include determinations of apparent viscosity, softening temperature, plastic period, and resolidificationtime for molten coal: (1) as a function of independent variations in coal type, heating rate, final temperature, gaseous atmosphere (inert, 0{sub 2} or H{sub 2}), and shear rate; and (2) in exploratory runs where coal is pretreated (preoxidation, pyridine extraction, metaplast cracking agents), before heating. The intra-coal inventory and molecular weight distribution of pyridine extractables will also be measured using a rapid quenching, electrical screen heater coal pyrolysis reactor. The yield of extractables is representative of the intra-coal inventory of plasticing agent (metaplast) remaining after quenching. Coal plasticity kinetics will then be mathematically modeled from metaplast generation and depletion rates, via a correlation between the viscosity of a suspension and the concentration of deformable medium (here metaplast) in that suspension. Work during this reporting period has been concerned with re-commissioning the rapid heating rate plastometer apparatus.

Darivakis, G.S.; Peters, W.A.; Howard, J.B.

1990-01-01T23:59:59.000Z

79

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

E-Print Network (OSTI)

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 ...

Hery, Travis M

2011-01-01T23:59:59.000Z

80

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  

Science Conference Proceedings (OSTI)

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.

Gat, N.

1982-04-26T23:59:59.000Z

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Approximate diagonalization  

E-Print Network (OSTI)

Abstract. We describe a new method of computing functions of highly non-normal matrices, by using the concept of approximate diagonalization. We formulate a conjecture about its efficiency, and provide both theoretical and numerical evidence in support of the conjecture. We apply the method to compute arbitrary real powers of highly non-normal matrices. Key words. Jordan matrices, ill-posedness, regularization, fractional powers, functional calculus, spectral theory.

E B Davies

2007-01-01T23:59:59.000Z

82

Expert Meeting Report: Exploring the Disconnect Between Rated and Field Performance of Water Heating Systems  

SciTech Connect

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

Hoeschele, M.; Weitzel, E.

2013-05-01T23:59:59.000Z

83

MEASURED AND CALCULATED HEATING AND DOSE RATES FOR THE HFIR HB4 BEAM TUBE AND COLD SOURCE  

SciTech Connect

The High Flux Isotope Reactor at the Oak Ridge National Laboratory was upgraded to install a cold source in horizontal beam tube number 4. Calculations were performed and measurements were made to determine heating within the cold source and dose rates within and outside a shield tunnel surrounding the beam tube. This report briefly describes the calculations and presents comparisons of the measured and calculated results. Some calculated dose rates are in fair to good agreement with the measured results while others, particularly those at the shield interfaces, differ greatly from the measured results. Calculated neutron exposure to the Teflon seals in the hydrogen transfer line is about one fourth of the measured value, underpredicting the lifetime by a factor of four. The calculated cold source heating is in good agreement with the measured heating.

Slater, Charles O [ORNL; Primm, Trent [ORNL; Pinkston, Daniel [ORNL; Cook, David Howard [ORNL; Selby, Douglas L [ORNL; Ferguson, Phillip D [ORNL; Bucholz, James A [ORNL; Popov, Emilian L [ORNL

2009-03-01T23:59:59.000Z

84

Activation, Heating and Exposure Rates for Mo?99 Experiments with 25?Disk Targets  

Science Conference Proceedings (OSTI)

An MCNPX model of the 25-disk target assembly inside the vacuum cube inside the shielded box was prepared. This was used to calculate heating and photon and neutron fluxes throughout the model. Production rates for photonuclear reaction products were calculated using the photon fluxes and ENDF/B-VII cross sections. Measured isomer to ground state yield ratios were used where available. Where not available the new correlation between spin deficit and isomer to ground state yield ratios presented at AccApp'11 was used. The photonuclear production rates and neutron fluxes were input to CINDER2008 for transmutation calculations. A cross section update file was used to supply (n,n') reactions missing from CINDER2008 libraries. Decay photon spectra produced by CINDER2008 were then used to calculate exposure rates using the MCNPX model. Two electron beam irradiations were evaluated. The first was for a thermal test at 15 MeV with 1300 {micro}A incident on one target end and the second was for a production test at 35 MeV with 350 {micro}A incident on both target ends (700 {micro}A total current on target). For the thermal test 1, 2, 3, 4, 5 and 6 h irradiation times were simulated, each followed by decay time steps out to 42 days. For the production test 6, 12, 18, 24, 30 and 36 h irradiation times were simulated followed by the same decay periods. For all simulations beam FWHMs in x and y were both assumed to be 6 mm. Simulations were run for Mo-100 enriched and natural Mo targets for both tests. It is planned that thermal test will be run for 4 h with natural target disks and production test will be run for 24 h with enriched target disks. Results for these two simulations only are presented in this report. Other results can be made available upon request. Post irradiation exposure rates were calculated at 30 cm distances from left, right, front and back of the following configurations: (1) Shielded box with everything in it (beam pipes, cooling pipes, vacuum cube, target housing weldment and target assembly), (2) Shielded box with everything in it except the target assembly, (3) Shielded box with nothing in it, (4) Target assembly taken outside of shielded box, (5) Target disks in cradle (target assembly with thermocouple weldment and flange removed), (6) Empty cradle, and (7) Target disks alone. Decay photon spectra from the CINDER2008 calculations were used as sources for the exposure rate calculations in the same model used for the flux calculations with beam on. As components were removed to simulate the seven cases considered the material compositions were changed to air and their respective sources were turned off. The MCNPX model geometry is plotted in Figure 1. The left and right detector locations for cases 1, 2 and 3 were 30 cm from the shielded box walls and 30 cm from the beam pipe openings in the left and right sides of the model (they are not in the beam line). A zoomed in plot of the target assembly alone is in Figure 2. Exposure rates for the seven cases are plotted as a function of time after irradiation in Figures 3, 4 and 5. To aid in comparison between the cases, all of these figures have been plotted using the same scale. Figures 3 and 4 are respectively the thermal and production test results for cases 1 through 6. Figure 5 includes case 7 results for both. Differences between cases 1 and 2 for both tests are not statistically significant showing that activation of components other than the target assembly, many of which are also shielding the target assembly, dominates exposure rates outside the shielded box. Case 3 shows the contribution from activation of the shield box itself. In front where shielded box wall is thickest box activation accounts for essentially all of the exposure rate outside. Differences between cases 4 and 5 are also minimal, showing that the contribution to target assembly exposure rates from the thermocouple flange and weldment are small compared to the target disks and cradle. From the numerical results the contribution is about 1%. Results for case 6, the cradle itself, are ini

Kelsey, Charles T. IV [Los Alamos National Laboratory

2012-05-09T23:59:59.000Z

85

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

E-Print Network (OSTI)

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

Ivanova, Anna

2010-01-01T23:59:59.000Z

86

Heating Rate within the Upper Ocean in Relation to its Bio–optical State  

Science Conference Proceedings (OSTI)

Solar radiation absorption and local heating within the upper layers of the open ocean are strongly influenced by the abundance of phytoplankton as depicted by the chlorophyll concentration. According to whether this concentration is high or low, ...

André Morel; David Antoine

1994-07-01T23:59:59.000Z

87

RATES  

NLE Websites -- All DOE Office Websites (Extended Search)

Marketing > RATES 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 Ancillary CV-RFS4 CV-SPR4 CV-SUR4 CV-EID4 CV-GID1 Future and Other Rates SNR Variable Resource Scheduling Charge FY12-FY16 (October 1, 2012) SNR Rates Process Calendar (PDF - 171K) Procedures Informal Process Transmission Action Items List (PDF - 144K) Power Action Item List updated on 4-27-10 (PDF - 155K) Power Action Item List (Quick links to relevant documents) Formal Process Rates Brochure (01/11/2011) (PDF - 900K) Appendix A - Federal Register Notice (01/03/2011) (PDF - 8000K) Appendix B - Central Valley Project Power Repayment Study (PDF - 22,322K) Appendix C - Development of the CVP Cost of Service Study (PDF - 2038K)

88

RATES  

NLE Websites -- All DOE Office Websites (Extended Search)

Planning & Projects Planning & Projects Power Marketing Rates You are here: SN Home page > Power Marketing > RATES Rates and Repayment Services Rates Current Rates Power Revenue Requirement Worksheet (FY 2014) (Oct 2013 - Sep 2014) (PDF - 30K) PRR Notification Letter (Sep 27, 2013) (PDF - 959K) FY 2012 FP% True-Up Calculations(PDF - 387K) Variable Resource Scheduling Charge FY12-FY16 (October 1, 2012) PRR Forecast FY14-FY17 (May 23, 2013) (PDF - 100K) Forecasted Transmission Rates (May 2013) (PDF - 164K) Past Rates 2013 2012 2011 2010 2009 Historical CVP Transmission Rates (April 2013) (PDF - 287K) Rate Schedules Power - CV-F13 - CPP-2 Transmission - CV-T3 - CV-NWT5 - PACI-T3 - COTP-T3 - CV-TPT7 - CV-UUP1 Ancillary - CV-RFS4 - CV-SPR4 - CV-SUR4 - CV-EID4 - CV-GID1 Federal Register Notices - CVP, COTP and PACI

89

RATES  

NLE Websites -- All DOE Office Websites (Extended Search)

RATES 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 4-27-10 (PDF - 155K) Power Action Item List (Quick links to relevant documents) Formal Process Rates Brochure (01/11/2011) (PDF - 900K) Appendix A - Federal Register Notice (01/03/2011) (PDF - 8000K) Appendix B - Central Valley Project Power Repayment Study (PDF - 22,322K) Appendix C - Development of the CVP Cost of Service Study (PDF - 2038K) Appendix D - Western Transmission System Facilities Map (PDF - 274K) Appendix E - Estimated FY12 FP and BR Customer (PDF - 1144K) Appendix F - Forecasted Replacements and Additions FY11 - FY16 (PDF - 491K) Appendix G - Definitions (PDF - 1758K) Appendix H - Acronyms (PDF - 720K)

90

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

Science Conference Proceedings (OSTI)

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.

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

91

On the Accuracy of the MINC approximation  

DOE Green Energy (OSTI)

The method of ''multiple interacting continua'' is based on the assumption that changes in thermodynamic conditions of rock matrix blocks are primarily controlled by the distance from the nearest fracture. The accuracy of this assumption was evaluated for regularly shaped (cubic and rectangular) rock blocks with uniform initial conditions, which are subjected to a step change in boundary conditions on the surface. Our results show that pressures (or temperatures) predicted from the MINC approximation may deviate from the exact solutions by as much as 10 to 15% at certain points within the blocks. However, when fluid (or heat) flow rates are integrated over the entire block surface, MINC-approximation and exact solution agree to better than 1%. This indicates that the MINC approximation can accurately represent transient inter-porosity flow in fractured porous media, provided that matrix blocks are indeed subjected to nearly uniform boundary conditions at all times.

Lai, C.H.; Pruess, K.; Bodvarsson, G.S.

1986-02-01T23:59:59.000Z

92

Nuclear mass inventory, photon dose rate and thermal decay heat of spent research reactor fuel assemblies  

SciTech Connect

As part of the Department of Energy`s spent nuclear fuel acceptance criteria, the mass of uranium and transuranic elements in spent research reactor fuel must be specified. These data are, however, not always known or readily determined. It is the purpose of this report to provide estimates of these data for some of the more common research reactor fuel assembly types. The specific types considered here are MTR, TRIGA and DIDO fuel assemblies. The degree of physical protection given to spent fuel assemblies is largely dependent upon the photon dose rate of the spent fuel material. These data also, are not always known or readily determined. Because of a self-protecting dose rate level of radiation (dose rate greater than 100 ren-x/h at I m in air), it is important to know the dose rate of spent fuel assemblies at all time. Estimates of the photon dose rate for spent MTR, TRIGA and DIDO-type fuel assemblies are given in this report.

Pond, R.B.; Matos, J.E.

1996-05-01T23:59:59.000Z

93

Rational Approximation for a Quasilinear Parabolic Equation  

E-Print Network (OSTI)

Approximation theorems, analogous to known results for linear elliptic equations, are obtained for solutions of the heat equation. Via the Cole-Hopf transformation, this gives rise to approximation theorems for a nonlinear parabolic equation, Burgers' equation.

P. M. Gauthier; N. Tarkhanov

2007-09-22T23:59:59.000Z

94

Effect of Heating Rate on the Thermodynamic Properties of Pulverized Coal  

SciTech Connect

This semi-annual technical progress report describes work performed under DOE Grant No.DE-FG22-96PC96224 during the period September 24, 1997 to April 23, 1998 which covers the third six months of the project. During this reporting period, several components of the electrodynamic balance measurement system, Single Particle Laboratory, Federal Energy Technology center, Morgantown, WV, were successfully calibrated. A large number of single polystyrenespheres covering a size range of 80 - 200 microns in diameter were caught in the electrodynamic balance. The size counts of their projected images obtained using the top video-based imaging system, bottom video-based imaging system, and diode-array imaging system were calibrated against the actual size of the particles to within ± 3 microns. Signals obtained by the particle position control system were also calibrated against the actual movement of a polystyrene particle in the balance to within ± 1 microns. Presently, calibration of the Single Color Pyrometer to measure coal particle temperature histories is in progress. Donation agreement for the Heated-Grid measurement system from our industrial partner, United Technologies Research Center (UTRC), CT, was obtained and the arrangement for the completion of the shipment of the grid system components from UTRC to CAU is in progress. Several theoretical analyses were conducted to improve the model performance of the present work and the results were compared with data available from our previous studies. These activities resulted in several publications including three conference papers, and one student poster paper during this reporting period.

Ramanathan Sampath

1998-05-01T23:59:59.000Z

95

Data Assimilation of Satellite-Derived Heating Rates as Proxy Surface Wetness Data into a Regional Atmospheric Mesoscale Model. Part I: Methodology  

Science Conference Proceedings (OSTI)

A satellite data assimilation method is developed which incorporates satellite-observed infrared heating rates into a mesoscale atmospheric model to retrieve model soil moisture. The method builds upon previous work with the model’s surface ...

Andrew S. Jones; Ingrid C. Guch; Thomas H. Vonder Haar

1998-03-01T23:59:59.000Z

96

Data Assimilation of Satellite-Derived Heating Rates as Proxy Surface Wetness Data into a Regional Atmospheric Mesoscale Model. Part II: A Case Study  

Science Conference Proceedings (OSTI)

A satellite data assimilation method is applied which incorporates satellite-observed heating infrared rates into a mesoscale atmospheric model to retrieve model soil moisture. In a 3D case study, the method is successful at retrieving realistic ...

Andrew S. Jones; Ingrid C. Guch; Thomas H. Vonder Haar

1998-03-01T23:59:59.000Z

97

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

DOE Green Energy (OSTI)

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.

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

2010-11-01T23:59:59.000Z

98

Equatorial Waves in the Upper Troposphere and Lower Stratosphere Forced by Latent Heating Estimated from TRMM Rain Rates  

Science Conference Proceedings (OSTI)

Equatorial atmospheric waves in the upper troposphere and lower stratosphere (UTLS), excited by latent heating, are investigated by using a global spectral model. The latent heating profiles are derived from the 3-hourly Tropical Rainfall ...

Jung-Hee Ryu; M. Joan Alexander; David A. Ortland

2011-10-01T23:59:59.000Z

99

THERMAL DESIGN METHODOLOGY FOR LOW FLOW RATE SINGLE-PHASE AND TWO-PHASE MICRO-CHANNEL HEAT SINKS  

E-Print Network (OSTI)

in Engine Cooling Systems,'' Experimental Heat Transfer, Fluid Mechanics, and Thermodynamics 1997, June 1997, ``A Correlation for Boiling Heat Transfer to Saturated Fluids in Convective Flow,'' Ind. Eng. Chem the engines in automotive applications. Heat is transferred essentially under subcooled flow boiling

Qu, Weilin

100

Heat and Buoyancy Budgets and Mixing Rates in the Upper Thermocline of the Indian and Global Oceans  

Science Conference Proceedings (OSTI)

Diapycnal and diathermal diffusivity values in the upper thermocline are estimated from buoyancy and heat budgets for water volumes bounded by isopycnals and isotherms, the air–sea interface, and coastline where applicable. Comprehensive analysis ...

Huai-Min Zhang; Lynne D. Talley

1998-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Facility location: distributed approximation  

Science Conference Proceedings (OSTI)

In this paper, we initiate the study of the approximability of the facility location problem in a distributed setting. In particular, we explore a trade-off between the amount of communication and the resulting approximation ratio. We give a distributed ... Keywords: distributed approximation, facility location, linear programming, primal-dual algorithms

Thomas Moscibroda; Rogert Wattenhofer

2005-07-01T23:59:59.000Z

102

Volatile compound evolution from the programmed temperature pyrolysis of Big Clifty and McKittrick tar sands at a 10 degrees C/min heating rate  

DOE Green Energy (OSTI)

Big Clifty (Kentucky) and McKittrick (California) tar sands were pyrolyzed at a 10{degrees}C/min heating rate from room temperature to 900{degrees}C. The volatile compounds were detected on-line and in real time by tandem mass spectrometry using MS and MS/MS detection. This paper reports the programmed temperature pyrolysis behaviors of Big Clifty and McKittrick tar sands and compares their results. 48 refs., 10 figs., 3 tabs.

Reynolds, J.G.

1989-11-01T23:59:59.000Z

103

Approximation of Stochastic Process  

E-Print Network (OSTI)

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

104

High temperature heat pipes for waste heat recovery  

SciTech Connect

Operation of heat pipes in air at temperatures above 1200/sup 0/K has been accomplished using SiC as a shell material and a chemical vapor deposit (CVD) tungsten inner liner for protection of the ceramic from the sodium working fluid. The CVD tungsten has been used as a distribution wick for the gravity assisted heat pipe through the development of a columnar tungsten surface structure, achieved by control of the metal vapor deposition rate. Wick performance has been demonstrated in tests at approximately 2 kW throughput with a 19-mm-i.d. SiC heat pipe. Operation of ceramic heat pipes in repeated start cycle tests has demonstrated their ability to withstand temperature rise rates of greater than 1.2 K/s.

Merrigan, M.A.; Keddy, E.S.

1980-01-01T23:59:59.000Z

105

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)

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

Bahrami, Majid

106

delta-Approximable Functions  

Science Conference Proceedings (OSTI)

In this paper we study several notions of approximability of functions in the framework of the BSS model. Denoting with ¿¿M the function computed by a BSS machine M when its comparisons are against -¿ rather than 0, we study ...

Charles Meyssonnier; Paolo Boldi; Sebastiano Vigna

2000-09-01T23:59:59.000Z

107

A Test of a Lapse Rate/Wind Speed Model for Estimating Heat Island Magnitude in an Urban Airshed  

Science Conference Proceedings (OSTI)

In the winter of 1975/76 a helicopter was used to obtain temperature profiles across the city of Calgary. This operation was supported by airborne measurements of wind speed and lapse rate at the edge of the city, upwind. Regression analysis ...

Lawrence C. Nkemdirim

1980-06-01T23:59:59.000Z

108

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

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.

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

2013-05-22T23:59:59.000Z

109

Oil shale retorting: a correlation of selected infrared absorbance bands with process heating rates and oil yeild  

DOE Green Energy (OSTI)

The measured absorbance for specific infrared bands of Colorado shale oil is correlated with process oil yield and retorting rate. The results show excellent correlations using bands associated with olefinic groups (910, 990 and 1640 cm/sup -1/); analyses were carried out using both quantitative and qualitative infrared methods. No pretreatment of the crude shale oil is required. The results are encouraging enough that, with further development, the method may have potential use as an on-line monitoring technique for various retorting processes.

Evans, R.A.; Campbell, J.H.

1979-01-01T23:59:59.000Z

110

Tests of Monte Carlo Independent Column Approximation With a Mixed-Layer Ocean Model  

NLE Websites -- All DOE Office Websites (Extended Search)

Tests of Monte Carlo Independent Column Tests of Monte Carlo Independent Column Approximation With a Mixed-Layer Ocean Model Petri Simo Järvenoja Heikki Järvinen Räisänen Finnish Meteorological Institute Figure 1. Root-mean-square sampling errors in local instant- aneous total (LW+SW) net flux at the surface and total radiative heating rate for the 1COL, CLDS, and REF approaches. Global rms values are given at the upper right hand corner of the plots. 1. Introduction The Monte Carlo Independent Column Approximation (McICA) separates the description of unresolved cloud structure from the radiative transfer solver very flexible ! unbiased with respect to ICA ! However, the radiative fluxes and heating rates contain conditional random errors ("McICA noise"). ? The topic of this poster: All previous tests of McICA

111

Heat reclaimer  

Science Conference Proceedings (OSTI)

A device for reclaiming heat from stove pipes and the like. A semi-circular shaped hollow enclosed housing with a highly thermal-conductive concave surface is mounted contactingly to surround approximately one-half of the circumference of the stove pipe. The concave surface is formed to contact the pipe at a maximum number of points along that surface. The hollow interior of the housing contains thin multi-surfaced projections which are integral with the concave surface and conductively transfer heat from the stove pipe and concave surface to heat the air in the housing. A fan blower is attached via an air conduit to an entrance opening in the housing. When turned on, the blower pushes the heated interior air out a plurality of air exit openings in the ends of the housing and brings in lower temperature outside air for heating.

Parham, F.

1985-04-09T23:59:59.000Z

112

Efficiency of unitary heat pumps  

SciTech Connect

The efficiencies of approximately 500 unitary heat pumps, from 30 different manufacturers, certified by the Air Conditioning and Refrigeration Institute (ARI) were examined. The certified units account for about 90% of all unitary heat pumps manufactured in the U.S. with a rated cooling capacity below 135,000 Btu/hr, and thus represent a comprehensive data file of the efficiencies of unitary heat pumps offered for sale in the U.S. A computer was used to group the heat pumps according to type and capacity, and to calculate their coefficients of performance (COP) using the data contained in ARI current Directory (April 1 to July 31, 1973) of Certified Unitary Heat Pumps. The results show that the COP of the heat pumps varied from a low of 1.5 to a high of 3.15 or a factor of 2 between the lowest and the highest efficiency, and that the average COP was 2.1 in cooling and 2.4 in heating. The variations of COP with heat pump size, type, manufacturer and outdoor temperature are presented.

Nwude, J.K.; Roman, A.J.

1973-11-01T23:59:59.000Z

113

Heating Rates in Tropical Anvils  

Science Conference Proceedings (OSTI)

The interaction of infrared and solar radiation with tropical cirrus anvils is addressed. Optical properties of the anvils are inferred from satellite observations and from high-altitude aircraft measurements. An infrared multiple-scattering ...

Thomas P. Ackerman; Kuo-Nan Liou; Francisco P. J. Valero; Leonhard Pfister

1988-05-01T23:59:59.000Z

114

Geothermal heating for Caliente, Nevada  

DOE Green Energy (OSTI)

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.

Wallis, F.; Schaper, J.

1981-02-01T23:59:59.000Z

115

CONTROL SYSTEM FOR SOLAR HEATING and COOLING  

E-Print Network (OSTI)

coil (G) of the absorption chiller (or boiler of a Rankineor heat input to the absorption chiller of approximately

Dols, C.

2010-01-01T23:59:59.000Z

116

Assessment of Hydrometeor Collection Rates from Exact and Approximate Equations. Part I: A New Approximate Scheme  

Science Conference Proceedings (OSTI)

The collection equation is analyzed for the case of two spherical hydrometeors with collection efficiency unity and exponential size distributions. When the fall velocities are significantly different a more general form of the conventional ...

Brian J. Gaudet; Jerome M. Schmidt

2005-01-01T23:59:59.000Z

117

Microwave heating for adsorbents regeneration and oil sands coke activation.  

E-Print Network (OSTI)

??Microwave heating has unique advantages compared to convection-radiation heating methods including fast heating rate and selective heating of objects. This thesis studied two applications of… (more)

Chen, Heng

2010-01-01T23:59:59.000Z

118

Scaled hydrogenic approximation wavefunctions. [Hartree-Fock approximation  

DOE Green Energy (OSTI)

Although widespread use of computer codes for the solution of Schrodinger equations makes available numerical Hartree-Fock model radial wave functions, there remains persistant interest in simple analytic expressions for atomic wave functions. One such frequency favored approach employs hydrogenic functions, suitably scaled, as approximate wave functions. The following note displays typical inaccuracies to be expected from such approximations. 13 references.

Shore, B.W.

1979-09-01T23:59:59.000Z

119

Heat exchanger  

DOE Patents (OSTI)

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

Wolowodiuk, Walter (New Providence, NJ)

1976-01-06T23:59:59.000Z

120

Ohmically heated high-density Z pinch  

SciTech Connect

The gross properties of a high-density (n approximately equal to 10$sup 27$ m$sup -3$), small-radius, (r = 10$sup -4$ m) gas-imbedded Z pinch have been examined considering only classical processes. The rate equation using only ohmic heating along with bremsstrahlung and radial heat transport shows that ohmic heating will rapidly take the pinch to thermonuclear temperatures for currents, I, greater than 1 MA. The radial heat loss for the pinch is very small for I greater than 1.5 MA. This suggests that the pinch could tolerate being driven to a nearby wall by an m = 1 kink. The laser technology for initiation of the small-diameter filament and the high-voltage technology for giving a 30-ns rise to a MA or more are available now. Some reactor considerations have been included. (auth)

Hammel, J.E.

1976-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Energy Efficiency Interest Rate Reduction Program | Department...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Interest Rate Reduction Program Energy Efficiency Interest Rate Reduction Program Eligibility Residential Savings For Heating & Cooling Home Weatherization Construction Commercial...

122

Table A4. Approximate Heat Content of Natural Gas, 1949 ...  

U.S. Energy Information Administration (EIA)

1954. 1,115 : 1,035 : 1,035 : 1,035 : 1,035 : 1,035 : 1,035 : 1955. 1,120 : 1,035 : 1,035 : 1,035 : 1,035 : 1,035 : 1,035 : 1956. 1,116 : 1,035 : ...

123

On the Beta Plane Approximation  

Science Conference Proceedings (OSTI)

The beta plane approximation as it is usually derived suffers from the difficulty that it is only valid if the quasi-geostrophic approximation is made. It is not valid for the underlying momentum and continuity equations. The problem in the ...

W. T. M. Verkley

1990-10-01T23:59:59.000Z

124

The Subinertial Mixed Layer Approximation  

Science Conference Proceedings (OSTI)

The density of the mixed layer is approximately uniform in the vertical but has dynamically important horizontal gradients. These nonuniformities in density result in a vertically sheared horizontal pressure gradient. Subinertial motions balance ...

W. R. Young

1994-08-01T23:59:59.000Z

125

The Quasi-Hydrostatic Approximation  

Science Conference Proceedings (OSTI)

Second-order expansion of the aspect ratio gives rise to simple equations with a quasi-hydrostatic approximation that perform far better than the classical hydrostatic system in the simulation of moist convection in a mesoscale model. It also ...

Isidoro Orlanski

1981-03-01T23:59:59.000Z

126

Heat pipe array heat exchanger  

DOE Patents (OSTI)

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

Reimann, Robert C. (Lafayette, NY)

1987-08-25T23:59:59.000Z

127

Linear Baroclinic instability with the Geostrophic Momentum Approximation  

Science Conference Proceedings (OSTI)

The linear Eady model of baroclinic instability with the geostrophic momentum (GM) approximation is solved analytically in physical space and shown to be identical to linear three-dimensional semigeostrophic theory. Both the growth rates and the ...

Peter R. Bannon

1989-02-01T23:59:59.000Z

128

Interface Heat Transfer Effects for Solidification Processes  

Science Conference Proceedings (OSTI)

The solidification rate of a casting is governed by the rate of heat extraction, which in turn is dominated by the rate of heat transfer across the casting-mold ...

129

Hydrogen Beyond the Classic Approximation  

E-Print Network (OSTI)

The classical nucleus approximation is the most frequently used approach for the resolution of problems in condensed matter physics.However, there are systems in nature where it is necessary to introduce the nuclear degrees of freedom to obtain a correct description of the properties.Examples of this, are the systems with containing hydrogen.In this work, we have studied the resolution of the quantum nuclear problem for the particular case of the water molecule.The Hartree approximation has been used, i.e. we have considered that the nuclei are distinguishable particles.In addition, we have proposed a model to solve the tunneling process, which involves the resolution of the nuclear problem for configurations of the system away from its equilibrium position

Scivetti, I

2003-01-01T23:59:59.000Z

130

Economic Analysis of Home Heating and Cooling  

E-Print Network (OSTI)

Over the last eleven years Houston Lighting & Power has raised utility rates an average of 17% per year. Over the last 3 1/2 years the utility rates have doubled. According to Houston City Magazine, Houstonians can expect future raises of 20-25% annually due to required construction of new utility plants to accommodate Houston's future growth. Utility costs could, and in many cases do, exceed the monthly mortgage payment. This has caused all to become concerned with what can be done to lower the utility bill for homes. In a typical Gulf Coast home approximately 50% of household utility costs are due to the air conditioning system, another 15-20% of utility costs are attributed to hot water heating. The remaining items in the home including lights, toaster, washer, dryer, etc. are relatively minor compared to these two "energy gulpers". Reducing air conditioning and hot water heating costs are therefore the two items on which homeowners should concentrate.

Wagers, H. L.

1984-01-01T23:59:59.000Z

131

Heat transfer via dropwise condensation on hydrophobic microstructured surfaces  

E-Print Network (OSTI)

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 ...

Ruleman, Karlen E. (Karlen Elizabeth)

2009-01-01T23:59:59.000Z

132

Heat pipe heat amplifier  

SciTech Connect

In a heat pipe combination consisting of a common condenser section with evaporator sections at either end, two working fluids of different vapor pressures are employed to effectively form two heat pipe sections within the same cavity to support an amplifier mode of operation.

Arcella, F.G.

1978-08-15T23:59:59.000Z

133

Heat Transfer Enhancement in Thermoelectric Power Generation.  

E-Print Network (OSTI)

??Heat transfer plays an important role in thermoelectric (TE) power generation because the higher the heat-transfer rate from the hot to the cold side of… (more)

Hu, Shih-yung

2009-01-01T23:59:59.000Z

134

Equivalence of Local Potential Approximations  

E-Print Network (OSTI)

In recent papers it has been noted that the local potential approximation of the Legendre and Wilson-Polchinski flow equations give, within numerical error, identical results for a range of exponents and Wilson-Fisher fixed points in three dimensions, providing a certain ``optimised'' cutoff is used for the Legendre flow equation. Here we point out that this is a consequence of an exact map between the two equations, which is nothing other than the exact reduction of the functional map that exists between the two exact renormalization groups. We note also that the optimised cutoff does not allow a derivative expansion beyond second order.

Tim R. Morris

2005-03-21T23:59:59.000Z

135

Radiant Heating  

Energy.gov (U.S. Department of Energy (DOE))

Radiant heating systems involve supplying heat directly to the floor or to panels in the walls or ceiling of a house. The systems depend largely on radiant heat transfer: the delivery of heat...

136

A Hierarchy of Approximations of the Master Equation Scaled by a Size Parameter  

Science Conference Proceedings (OSTI)

Solutions of the master equation are approximated using a hierarchy of models based on the solution of ordinary differential equations: the macroscopic equations, the linear noise approximation and the moment equations. The advantage with the approximations ... Keywords: Linear noise approximation, Master equation, Moment equations, Reaction rate equations

Lars Ferm; Per Lötstedt; Andreas Hellander

2008-02-01T23:59:59.000Z

137

Transient natural convection in heated inclined tubes  

SciTech Connect

To simulate natural convection flow patterns in directionally drilled wellbores, experiments and analyses were conducted for a circular tube with length-to-diameter (L/D) ratio of 36 at angles of 0{degree}, 20{degree}, and 35{degree} from the vertical. The tube was heated at the bottom and cooled at the top, and the insulation was adjusted so that approximately one- to two-thirds of the power dissipated was transferred through the tube wall to the surroundings. An aqueous solution of polyvinyl alcohol was employed as the working fluid in order to obtain low Rayleigh numbers corresponding to conditions in geothermal wellbores. Results were primarily qualitative but were useful in providing insight into the phenomena occurring. Steady-state temperature distributions were measured for the three orientations and for several heating rates to demonstrate the effects of tube angle and Rayleigh number. transient measurements of the temperature distribution were obtained during cooling from a higher temperature without a heat source to calibrate the heat losses. With the electrical heat source, temporal data were taken during heating to examine the approach to steady state. Quasi-steady flow conditions were approached rapidly, but the overall time constant of the apparatus was of the order of one-third of a day. Predictions with the three-dimensional TEMPEST code were first tested by comparison with simple conduction analyses. Comparison with actual data showed good agreement of the predicted temperature levels for the maximum inclination, 35{degree}, and slightly poorer agreement for the other limit, a vertical tube. Trends of temperature level and Nusselt number with heating rate or Rayleigh number were reasonable, but the predicted variation of the end Nusselt number versus inclination was in the opposite direction from the experiment. 75 refs., 20 figs., 8 tabs.

McEligot, D.M. (Westinghouse Electric Corp., Middletown, RI (USA). Oceanic Div.); Denbow, D.A. (Software AG of North America, Inc., Lakewood, CO (USA)); Murphy, H.D. (Los Alamos National Lab., NM (USA))

1990-05-01T23:59:59.000Z

138

TRANSPARENT HEAT MIRRORS FOR PASSIVE SOLAR HEATING APPLICATIONS  

E-Print Network (OSTI)

deposition rates and production costs were reviewed todiscussion of heat mirror production cost Most of our effortcoating plastic film. Production costs for coating glass

Selkowitz, S.

2011-01-01T23:59:59.000Z

139

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

DOE Green Energy (OSTI)

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

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

1981-11-08T23:59:59.000Z

140

Design and technology of heat pipes for cooling and heat exchange  

SciTech Connect

This new book presents a comprehensive account of heat pipe design, technology, and operation. It is based on insights and techniques developed by the author during more than twenty years of investigating high-performance heat pipe systems. The book provides information on a unique device with the capability to transport heat isothermally at high rates with no external power input. Emphasis is on high-performance liquid metal heat pipes, although nonliquid metal heat pipes are treated, as well. The first three chapters deal with the nonmathematical background for understanding heat pipe operation and heat transport capability. Remaining chapters detail heat pipe characteristics and design methods. Of special interest are simplified equations for obtaining heat pipe heat transport limits, heat pipe heat exchangers, heat pipe transient behavior, and inverted (nonwetting) heat pipes. Operational boundaries on heat pipe temperature and heat transport rate are described, and step-by-step procedures are given for involved calculations.

Silverstein, C.C.

1992-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Fundamental heat transfer experiments of heat pipes for turbine cooling  

SciTech Connect

Fundamental heat transfer experiments were carried out for three kinds of heat pipes that may be applied to turbine cooling in future aero-engines. In the turbine cooling system with a heat pipe, heat transfer rate and start-up time of the heat pipe are the most important performance criteria to evaluate and compare with conventional cooling methods. Three heat pipes are considered, called heat pipe A, B, and C, respectively. All heat pipes have a stainless steel shell and nickel sintered powder metal wick. Sodium (Na) was the working fluid for heat pipes A and B; heat pipe C used eutectic sodium-potassium (NaK). Heat pipes B and C included noncondensible gas for rapid start-up. There were fins on the cooling section of heat pipes. In the experiments, an infrared image furnace supplied heat to the heat pipe simulating turbine blade surface conditions. In the results, heat pipe B demonstrated the highest heat flux of 17 to 20 W/cm{sup 2}. The start-up time was about 6 minutes for heat pipe B and about 6 minutes for heat pipe A. Thus, adding noncondensible gas effectively reduced start-up time. Although NaK is a liquid phase at room temperature, the start-up time of heat pipe C (about 7 to 8 minutes) was not shorter than the heat pipe B. The effect of a gravitational force on heat pipe performance was also estimated by inclining the heat pipe at an angle of 90 deg. There was no significant gravitational dependence on heat transport for heat pipes including noncondensible gas.

Yamawaki, S. [Ishikawajima-Harima Heavy Industries Co., Ltd., Tokyo (Japan); Yoshida, T.; Taki, M.; Mimura, F. [National Aerospace Lab., Tokyo (Japan)

1998-07-01T23:59:59.000Z

142

Heating Alloys  

Science Conference Proceedings (OSTI)

...are used in many varied applications--from small household appliances to large industrial process heating systems and furnaces. In appliances or industrial process heating, the heating elements are usually either open

143

Effects of the Boussinesq Approximation on the Results of Strongly-Buoyant Plume Calculations  

Science Conference Proceedings (OSTI)

Nearly all mathematical models which are commonly used to predict the dispersion of chimney gases in the atmosphere or heated water discharges in the aquatic environment employ the so-called Boussinesq approximation. It is part of this ...

M. Schatzmann; A. J. Policastro

1984-01-01T23:59:59.000Z

144

Infrared Thermography applied to measurement of Heat transfer coefficient of water in a pipe heated by Joule effect  

E-Print Network (OSTI)

. Internal sources of heat are due to convection from flow of the heat transfer fluid through the pipes. Heat (material, diameter, spacing, and burial depth), (4) system flow rates, (5) heat transfer fluid properties · heat transfer fluid = 42% propylene glycol @ a flow rate of 350 gpm · heat pump model = Water Furnace

145

Chemical heat pump  

DOE Patents (OSTI)

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.

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

1980-01-01T23:59:59.000Z

146

Heating Systems  

Energy.gov (U.S. Department of Energy (DOE))

A variety of heating technologies are available today. In addition to heat pumps, which are discussed separately, many homes and buildings use the following approaches:

147

Definition: Heat | Open Energy Information  

Open Energy Info (EERE)

Heat Heat Jump to: navigation, search Dictionary.png Heat Heat is the form of energy that is transferred between systems or objects with different temperatures (flowing from the high-temperature system to the low-temperature system). Also referred to as heat energy or thermal energy. Heat is typically measured in Btu, calories or joules. Heat flow, or the rate at which heat is transferred between systems, has the same units as power: energy per unit time (J/s).[1][2][3][4] View on Wikipedia Wikipedia Definition In physics and chemistry, heat is energy in transfer between a system and its surroundings other than by work or transfer of matter. The transfer can occur in two simple ways, conduction, and radiation, and in a more complicated way called convective circulation. Heat is not a property

148

MGCR HEAT EXCHANGER TEST PROGRAM. Final Report  

SciTech Connect

The Maritime Gas-cooled Reactor (MGCR) project has conipleted the study and design of a closed-cycle gasturbine propulsion plant utilizing a helium- cooled nuclear reactor as the heat source. The cycle employs a counterflow shell- and-tube regenerator to attain a high thermodynamic cycle efficiency. A heat exchanger test program was conducted to compile and correlate sufficient experimental data for the aerodynamic and thermal design of the prototype regenerator. The model heat exchanger was similar in configaration to the prototype unit. The pressure-drop and heat-transfer performance of a compact parallel-flow tube bundle is given hoth in the unsupported configuration and with airfoil-shaped tube supports distributed along the bundle. The Fanning friction factor with the airfoil-shaped supports is approximately 70% greater than for the unsupported tube configuration. The airfoil supports effect a 40% increase in Colburn's heat transfer factor, j, over the unsupported configuration. Determinations of the unsupported-tube values of friction factor and Colburn-j agreed well with the literature. A section is devoted to the application of these data to the design of exchangers. The correlated data, representing some 1200 individual runs, cover a range of Reynolds number from 10,000 to 500,000. The moderate pressure-drop increment due to the airfoil-shaped supports, in conjunction with the favorable increase in heat-transfer rate, becomes especially important in the design of compact gas-to-gas heat exchangers with very low friction pressure losses. The concluding section of the report compares the size, weight, and cost of conventional baffled-shell units and the MGCR design for the requirements of the MGCR cycle. The MGCR design was one-fifth the volume, one-fourth the weight, and one-third the cost of comparable baffled-shell units. (auth)

Paulson, H.C. II

1961-04-01T23:59:59.000Z

149

Saturated Pseudoadiabats—A Noniterative Approximation  

Science Conference Proceedings (OSTI)

Two noniterative approximations are presented for saturated pseudoadiabats (also known as moist adiabats). One approximation determines which moist adiabat passes through a point of known pressure and temperature, such as through the lifting ...

Atoossa Bakhshaii; Roland Stull

2013-01-01T23:59:59.000Z

150

Enabling ?-approximate querying in sensor networks  

Science Conference Proceedings (OSTI)

Data approximation is a popular means to support energy-efficient query processing in sensor networks. Conventional data approximation methods require users to specify fixed error bounds a prior to address the trade-off between result accuracy ...

Liu Yu; Jianzhong Li; Hong Gao; Xiaolin Fang

2009-08-01T23:59:59.000Z

151

The Broadband Heating Rate Profile (BBHRP) VAP  

NLE Websites -- All DOE Office Websites (Extended Search)

Ellingson Florida State University Tallahassee, Florida M. H. Zhang State University of New York at Albany Albany, New York Stony Brook R. A. Ferrare National Aeronautics and...

152

Heat Rate Improvement Reference Manual: Training Guidelines  

Science Conference Proceedings (OSTI)

Performance optimization of fossil power plants has always been a high priority within the electric power industry. However, it has become of paramount importance in meeting the challenges mandated by operating within a competitive environment. Recently, many power producers have downsized and currently lack experienced staff required to maintain optimal performance. Thus, a resource was needed to capture the lost experience to aid in the retaining of less experienced personnel. The objective of this pro...

1999-12-07T23:59:59.000Z

153

Approximations: Atomic Ref. Data Elect. Struct. Calculations  

Science Conference Proceedings (OSTI)

... where ? xc (?) is the exchange-correlation energy per particle for the uniform electron gas of density ?. This approximation ...

154

The multiple absorption coefficient zonal method (MACZM), an efficient computational approach for the analysis of radiative heat transfer in multidimensional inhomogeneous nongray media  

E-Print Network (OSTI)

of Radiative Heat Transfer, the P-3 Approximation”, AIAAMedia”, Journal of Heat Transfer, Vol. 109, No. 3 (1987),Media”, Numerical Heat Transfer, Part B, Fundamentals, Vol.

Yuen, W W

2006-01-01T23:59:59.000Z

155

Exact microscopic theory of electromagnetic heat transfer between a dielectric sphere and plate  

E-Print Network (OSTI)

Near-field electromagnetic heat transfer holds great potential for the advancement of nanotechnology. Whereas far-field electromagnetic heat transfer is constrained by Planck's blackbody limit, the increased density of states in the near-field enhances heat transfer rates by orders of magnitude relative to the conventional limit. Such enhancement opens new possibilities in numerous applications, including thermal-photo-voltaics, nano-patterning, and imaging. The advancement in this area, however, has been hampered by the lack of rigorous theoretical treatment, especially for geometries that are of direct experimental relevance. Here we introduce an efficient computational strategy, and present the first rigorous calculation of electromagnetic heat transfer in a sphere-plate geometry, the only geometry where transfer rate beyond blackbody limit has been quantitatively probed at room temperature. Our approach results in a definitive picture unifying various approximations previously used to treat this problem, and provides new physical insights for designing experiments aiming to explore enhanced thermal transfer.

Clayton Otey; Shanhui Fan

2011-03-14T23:59:59.000Z

156

Energy Model Development and Heating Energy Investigation of the Nested Thermal Envelope Design (NTED (tm)).  

E-Print Network (OSTI)

??Space heating accounts for approximately 60% of residential energy use in Canada. Minimizing envelope heat losses is one approach to reducing this percentage. Preliminary research… (more)

DIxon, Erin Elizabeth

2010-01-01T23:59:59.000Z

157

Stability of thermal structures with an internal heating source  

E-Print Network (OSTI)

We study the thermal equilibrium and stability of isobaric, spherical structures having a radiation source located at its center. The thermal conduction coefficient, external heating and cooling rates are represented as power laws of the temperature. The internal heating decreases with distance from the source r approximately as exp(-tau)/(r**2), being tau the optical depth. We find that the influence of the radiation source is important only in the central region, but its effect is enough to make the system thermally unstable above a certain threshold central temperature. This threshold temperature decreases as the internal heating efficiency increases, but, otherwise, it does not depend on the structure size. Our results suggest that a solar-like star migrating into a diffuse interstellar region may destabilize the surrounding medium.

Sanchez, Nestor

2008-01-01T23:59:59.000Z

158

Stability of thermal structures with an internal heating source  

E-Print Network (OSTI)

We study the thermal equilibrium and stability of isobaric, spherical structures having a radiation source located at its center. The thermal conduction coefficient, external heating and cooling rates are represented as power laws of the temperature. The internal heating decreases with distance from the source r approximately as exp(-tau)/(r**2), being tau the optical depth. We find that the influence of the radiation source is important only in the central region, but its effect is enough to make the system thermally unstable above a certain threshold central temperature. This threshold temperature decreases as the internal heating efficiency increases, but, otherwise, it does not depend on the structure size. Our results suggest that a solar-like star migrating into a diffuse interstellar region may destabilize the surrounding medium.

Nestor Sanchez; Eugenio Lopez

2008-03-10T23:59:59.000Z

159

HEAT TRANSFER METHOD  

DOE Patents (OSTI)

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

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

1960-08-30T23:59:59.000Z

160

Compare All CBECS Activities: District Heat Use  

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

District Heat Use District Heat Use Compare Activities by ... District Heat Use Total District Heat Consumption by Building Type Commercial buildings in the U.S. used a total of approximately 433 trillion Btu of district heat (district steam or district hot water) in 1999. There were only five building types with statistically significant district heat consumption; education buildings used the most total district heat. Figure showing total district heat consumption by building type. If you need assistance viewing this page, please call 202-586-8800. District Heat Consumption per Building by Building Type Health care buildings used the most district heat per building. Figure showing district heat consumption per building by building type. If you need assistance viewing this page, please call 202-586-8800.

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

The effect of heat conduction on the interaction of disk and corona around black holes  

E-Print Network (OSTI)

Heat conduction plays an important role in the balance between heating and cooling in many astrophysical objects, e.g. cooling flows in clusters of galaxies. Here we investigate the effect of heat conduction on the interaction between a cool disk and a hot corona around black holes. Using the one-radial-zone approximation, we study the vertical structure of the disk corona and derive evaporation and coronal mass flow rates for various reduced thermal conductivities. We find lower evaporation rates and a shift in the evaporation maxima to smaller radii. This implies that the spectral state transition occurs at a lower mass flow rate and a disk truncation closer to the black hole. Reductions of thermal conductivity are thought to be magnetically caused and might vary from object to object by a different configuration of the magnetic fields.

E. Meyer-Hofmeister; F. Meyer

2005-12-21T23:59:59.000Z

162

An accurate approximation to the average error probability of cooperative diversity in Nakagami-m fading  

Science Conference Proceedings (OSTI)

A new approximation to the average symbol error rate of cooperative diversity is derived for independent and non-identically distributed Nakagami-m fading channels. The new approximation has the same computational complexity as previous lower bounds ... Keywords: Nakagami, cooperative diversity, fading channels, symbol error rate

Norman C. Beaulieu; Yunfei Chen

2010-09-01T23:59:59.000Z

163

Heat Conduction  

Science Conference Proceedings (OSTI)

Table 2   Differential equations for heat conduction in solids...conduction in solids General form with variable thermal properties General form with constant thermal properties General form, constant properties, without heat

164

Heat exchanger  

DOE Patents (OSTI)

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

Daman, Ernest L. (Westfield, NJ); McCallister, Robert A. (Mountain Lakes, NJ)

1979-01-01T23:59:59.000Z

165

Convex Approximations of Chance Constrained Programs  

E-Print Network (OSTI)

given point is to use Monte-Carlo simulation, and this becomes too costly when ? ...... approach to stochastic programming of heating oil, Management Science, ...

166

Nonlinear thermomechanical finite-element modeling, analysis and characterization of multi-turn oscillating heat pipes .  

E-Print Network (OSTI)

??Oscillating heat pipes (OHPs) are promising heat dissipation devices for modern electronic systems due to their high heat transfer rate, simple construction and low manufacturing… (more)

Peng, Hao

2012-01-01T23:59:59.000Z

167

Rate Schedules  

Energy.gov (U.S. Department of Energy (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...

168

Illustrative Calculation of Economics for Heat Pump and "Grid...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Illustrative Calculation of Economics for Heat Pump and "Grid-Enabled" Water Heaters Illustrative Calculation of Economics for Heat Pump and "Grid-Enabled" Water Heaters Rate...

169

Experimental study on turbulent natural convection heat transfer in ...  

Science Conference Proceedings (OSTI)

Feb 16, 2010 ... ments are conducted to investigate flow and heat transfer ... turbulent region, the heat transfer deterioration occurs for a bubble flow rate Q = 33 ...

170

Heat transfer via dropwise condensation on hydrophobic microstructured surfaces.  

E-Print Network (OSTI)

??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… (more)

Ruleman, Karlen E. (Karlen Elizabeth)

2009-01-01T23:59:59.000Z

171

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...

172

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* ... 222 194 17...

173

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 ... 2,100...

174

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* ... 1,928 1,316...

175

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...

176

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...

177

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...

178

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...

179

An approximation trichotomy for Boolean #CSP  

E-Print Network (OSTI)

We give a trichotomy theorem for the complexity of approximately counting the number of satisfying assignments of a Boolean CSP instance. Such problems are parameterised by a constraint language specifying the relations that may be used in constraints. If every relation in the constraint language is affine then the number of satisfying assignments can be exactly counted in polynomial time. Otherwise, if every relation in the constraint language is in the co-clone IM_2 from Post's lattice, then the problem of counting satisfying assignments is complete with respect to approximation-preserving reductions in the complexity class #RH\\Pi_1. This means that the problem of approximately counting satisfying assignments of such a CSP instance is equivalent in complexity to several other known counting problems, including the problem of approximately counting the number of independent sets in a bipartite graph. For every other fixed constraint language, the problem is complete for #P with respect to approximation-prese...

Dyer, Martin; Jerrum, Mark

2007-01-01T23:59:59.000Z

180

Improved Error Bounds for the Adiabatic Approximation  

E-Print Network (OSTI)

Since the discovery of adiabatic quantum computing, a need has arisen for rigorously proven bounds for the error in the adiabatic approximation. We present in this paper, a rigorous and elementary derivation of upper and lower bounds on the error incurred from using the adiabatic approximation for quantum systems. Our bounds are often asymptotically tight in the limit of slow evolution for fixed Hamiltonians, and are used to provide sufficient conditions for the application of the adiabatic approximation. We show that our sufficiency criteria exclude the Marzlin--Sanders counterexample from the class of Hamiltonians that obey the adiabatic approximation. Finally, we demonstrate the existence of classes of Hamiltonians that resemble the Marzlin--Sanders counterexample Hamiltonian, but also obey the adiabatic approximation.

Cheung, Donny; Wiebe, Nathan

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Determination of approximate nonlinear self-adjointenss and approximate conservation law  

E-Print Network (OSTI)

Approximate nonlinear self-adjointness is an effective method to construct approximate conservation law of perturbed partial differential equations (PDEs). In this paper, we study the relations between approximate nonlinear self-adjointness of perturbed PDEs and nonlinear self-adjointness of the corresponding unperturbed PDEs, and consequently provide a simple approach to discriminate approximate nonlinear self-adjointness of perturbed PDEs. Moreover, a succinct approximate conservation law formula by virtue of the known conservation law of the unperturbed PDEs is given in an explicit form. As an application, we classify a class of perturbed wave equations to be approximate nonlinear self-adjointness and construct the general approximate conservation laws formulae. The specific examples demonstrate that approximate nonlinear self-adjointness can generate new approximate conservation laws.

Zhi-Yong Zhang

2013-01-19T23:59:59.000Z

182

Heat transfer and pressure drop measurements in an air/molten salt direct-contact heat exchanger  

SciTech Connect

This paper presents a comparison of experimental data with a recently published model of heat exchange in irrigated packed beds. Heat transfer and pressure drop were measured in a 150 mm (ID) column with a 610-mm bed of metal Pall rings. Molten nitrate salt and preheated air were the working fluids with a salt inlet temperature of approximately 440{degree}C and air inlet temperatures of approximately 230{degree}C. A comparison between the experimental data and the heat transfer model is made on the basis of heat transfer from the salt. For the range of air and salt flow rates tested, 0.3 to 1.2 kg/m{sup 2} s air flow and 6 to 18 kg/m{sup 2} s salt flow, the data agree with the model within 22% standard deviation. In addition, a model for the column pressure drop was validated, agreeing with the experimental data within 18% standard deviation over the range of column pressure drop from 40 to 1250 Pa/m. 25 refs., 7 figs., 2 tabs.

Bohn, M.S.

1988-11-01T23:59:59.000Z

183

Rates - WAPA-137 Rate Order  

NLE Websites -- All DOE Office Websites (Extended Search)

WAPA-137 Rate Order WAPA-137 Rate Order 2009 CRSP Management Center Customer Rates Second Step Presentation from the June 25, 2009, Customer Meeting Handout Materials from the June 25, 2009, Customer Meeting Customer Comment Letters ATEA CREDA Farmington ITCA AMPUA Rate Adjustment Information The second step of WAPA-137 SLCA/IP Firm Power, CRSP Transmission and Ancillary Services rate adjustment. FERC Approval of Rate Order No. WAPA-137 Notice Of Filing for Rate Order No. WAPA-137 Published Final FRN for Rate Order No. WAPA-137 Letter to Customers regarding the published Notice of Extension of Public Process for Rate Order No. WAPA-137 Published Extension of Public Process for Rate Order No. WAPA-137 FRN Follow-up Public Information and Comment Forum Flier WAPA-137 Customer Meetings and Rate Adjustment Schedule

184

Water heater heat reclaimer  

SciTech Connect

This invention relates to the conservation of energy in a domestic gas water heater by utilizing the hot exhaust gases in a gas water heater for the preheating of the incoming unheated water into the water heater. The exhaust gases from a domestic gas water heater carry wasted heat and the present invention provides a mean to reclaim part of the wasted heat for the preheating of the incoming unheated water during hot water usage periods. During non hot water usage periods the heat in the exhaust gases is not reclaimed to prevent overheating of the water and also to prevent the formation of water deposit in the preheating assembly or heat reclaimer. During the non hot water usage periods the heat produced in the water heater is normally needed only to maintain the desired water temperature of the stored water in the water tank of the water heater. Due to the rapid heating or recovery rate, the present invention enables the use of a smaller water heater. The use of a smaller water heater reduces the normal heat loss from the stored hot water thereby further reduces energy consumption.

Wie, C.T.

1983-08-09T23:59:59.000Z

185

Polymer state approximations of Schroedinger wave functions  

E-Print Network (OSTI)

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

Klaus Fredenhagen; Felix Reszewski

2006-06-21T23:59:59.000Z

186

Improved approximations for k-exchange systems  

Science Conference Proceedings (OSTI)

Submodular maximization and set systems play a major role in combinatorial optimization. It is long known that the greedy algorithm provides a 1/(k + 1)-approximation for maximizing a monotone submodular function over a k-system. For the ...

Moran Feldman; Joseph Naor; Roy Schwartz; Justin Ward

2011-09-01T23:59:59.000Z

187

N-Stream Approximations to Radiative Transfer  

Science Conference Proceedings (OSTI)

Schuster's two-stream approximation is first derived from Chandrasekhar's radiative transfer equation, and then generalized to an arbitrary number of streams. The resulting technique for solving the transfer equation that is similar to the ...

Charles Acquista; Frederick House; James Jafolla

1981-07-01T23:59:59.000Z

188

Linear source approximation in CASMO5  

Science Conference Proceedings (OSTI)

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

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

2012-07-01T23:59:59.000Z

189

Blind multiuser detection based on kernel approximation  

Science Conference Proceedings (OSTI)

A kernel based multiuser detection (MUD) scheme in code-division multiple-access (CDMA) system is proposed. In this scheme, the support vector (SV) under support vector (SVM) framework is obtained through a kernel sparsity approximation, which regulates ...

Tao Yang; Bo Hu

2006-05-01T23:59:59.000Z

190

Casimir forces beyond the proximity approximation  

E-Print Network (OSTI)

The proximity force approximation (PFA) relates the interaction between closely spaced, smoothly curved objects to the force between parallel plates. Precision experiments on Casimir forces necessitate, and spur research ...

Bimonte, G.

191

Liquid metal heat pipe behavior under transient cooling and heating  

SciTech Connect

This paper describes the results of an experimental investigation of the transient behavior of a liquid metal heat pipe. A 0.457 m long, screen-wick, sodium heat pipe with 0.0127 m outer diameter was tested in sodium loop facility. The heat pipe reversed under a pulse heat load applied at the condenser. The time at which the heat pipe reversed was dependent of the heat pipe properties, the sodium loop flow rate and heating conditions at the condenser. The start-up and the operational shut-down by forced cooling of the condenser were also studied. During the start-up process, at least part of the heat pipe was active. The active region extended gradually down to the end of the condenser until all working fluid in the heat pipe was molten. With forced cooling at the condenser, the heat pipe approached its heat transport limit before section of the condenser became frozen. The measured heat transport limit was in agreement with the theoretical value. 5 refs.

Nguyen, H.X.; Hahn, T.O.; Hahn, O.J.; Chow, L.C.; Tagavi, K.A.; Morgan, M.J. (Kentucky, University, Lexington (United States) USAF, Wright Laboratory, Wright-Patterson AFB, OH (United States))

1992-01-01T23:59:59.000Z

192

COOLING AND HEATING FUNCTIONS OF PHOTOIONIZED GAS  

SciTech Connect

Cooling and heating functions of cosmic gas are crucial ingredients for any study of gas dynamics and thermodynamics in the interstellar and intergalactic media. As such, they have been studied extensively in the past under the assumption of collisional ionization equilibrium. However, for a wide range of applications, the local radiation field introduces a non-negligible, often dominant, modification to the cooling and heating functions. In the most general case, these modifications cannot be described in simple terms and would require a detailed calculation with a large set of chemical species using a radiative transfer code (the well-known code Cloudy, for example). We show, however, that for a sufficiently general variation in the spectral shape and intensity of the incident radiation field, the cooling and heating functions can be approximated as depending only on several photoionization rates, which can be thought of as representative samples of the overall radiation field. This dependence is easy to tabulate and implement in cosmological or galactic-scale simulations, thus economically accounting for an important but rarely included factor in the evolution of cosmic gas. We also show a few examples where the radiation environment has a large effect, the most spectacular of which is a quasar that suppresses gas cooling in its host halo without any mechanical or non-radiative thermal feedback.

Gnedin, Nickolay Y. [Particle Astrophysics Center, Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Hollon, Nicholas, E-mail: gnedin@fnal.gov [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States)

2012-10-15T23:59:59.000Z

193

An approximation trichotomy for Boolean #CSP  

E-Print Network (OSTI)

We give a trichotomy theorem for the complexity of approximately counting the number of satisfying assignments of a Boolean CSP instance. Such problems are parameterised by a constraint language specifying the relations that may be used in constraints. If every relation in the constraint language is affine then the number of satisfying assignments can be exactly counted in polynomial time. Otherwise, if every relation in the constraint language is in the co-clone IM2 from Post’s lattice, then the problem of counting satisfying assignments is complete with respect to approximation-preserving reductions in the complexity class #RH?1. This means that the problem of approximately counting satisfying assignments of such a CSP instance is equivalent in complexity to several other known counting problems, including the problem of approximately counting the number of independent sets in a bipartite graph. For every other fixed constraint language, the problem is complete for #P with respect to approximation-preserving reductions, meaning that there is no fully polynomial randomised approximation scheme for counting satisfying assignments unless NP=RP. 1

Martin Dyer; Leslie Ann Goldberg; Mark Jerrum

2007-01-01T23:59:59.000Z

194

Energy Rating  

E-Print Network (OSTI)

Consistent, accurate, and uniform ratings based on a single statewide rating scale Reasonable estimates of potential utility bill savings and reliable recommendations on cost-effective measures to improve energy efficiency Training and certification procedures for home raters and quality assurance procedures to promote accurate ratings and to protect consumers Labeling procedures that will meet the needs of home buyers, homeowners, renters, the real estate industry, and mortgage lenders with an interest in home energy ratings

Cabec Conference; Rashid Mir P. E

2009-01-01T23:59:59.000Z

195

Insertion Rates  

Science Conference Proceedings (OSTI)

HOME > Insertion Rates. TECH HEADLINES. Research Explores a New Layer in Additive Manufacturin... Grand Opening Slated for Electron Microscopy Facility.

196

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

SciTech Connect

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

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

1996-04-05T23:59:59.000Z

197

Heating by the Raman instability  

Science Conference Proceedings (OSTI)

Computer simulations are presented of the reflection and heating due to stimulated Raman backscatter of intense laser light in large regions of underdense plasma. The heated electron distribution is found to be approximately a Maxwellian of temperature (m/sub e//2)v/sub p//sup 2/, where v/sub p/ is the phase velocity of the electron plasma wave. A simple model of the reflection is presented. Raman may cause a pre-heat problem with large laser fusion reactor targets.

Estabrook, K.G.; Kruer, W.L.

1980-04-11T23:59:59.000Z

198

Heat Stroke  

NLE Websites -- All DOE Office Websites (Extended Search)

stress, from exertion or hot environments, places stress, from exertion or hot environments, places workers at risk for illnesses such as heat stroke, heat exhaustion, or heat cramps. Heat Stroke A condition that occurs when the body becomes unable to control its temperature, and can cause death or permanent disability. Symptoms â–  High body temperature â–  Confusion â–  Loss of coordination â–  Hot, dry skin or profuse sweating â–  Throbbing headache â–  Seizures, coma First Aid â–  Request immediate medical assistance. â–  Move the worker to a cool, shaded area. â–  Remove excess clothing and apply cool water to their body. Heat Exhaustion The body's response to an excessive loss of water and salt, usually through sweating. Symptoms â–  Rapid heart beat â–  Heavy sweating â–  Extreme weakness or fatigue â– 

199

Heat transfer. [heat transfer roller employing a heat pipe  

SciTech Connect

A heat transfer roller embodying a heat pipe is disclosed. The heat pipe is mounted on a shaft, and the shaft is adapted for rotation on its axis.

Sarcia, D.S.

1978-05-23T23:59:59.000Z

200

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

Science Conference Proceedings (OSTI)

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

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

2005-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Sparse Approximation via Penalty Decomposition Methods  

E-Print Network (OSTI)

The error rate of (v, w) for ... In addition, the average logistic loss, the error rate and the CPU time (in seconds) for both ...... decision making in the human brain.

202

Rate schedule  

NLE Websites -- All DOE Office Websites (Extended Search)

Firm Power Service Provided by Rate/Charges Firm Power Service Provided by Rate/Charges Rate/Charges Effective Through (or until superceded) Firm Sales (SLIP-F9) Composite Rate SLIP 29.62 mills/kWh 9/30/2015 Demand Charge SLIP $5.18/kW-month 9/30/2015 Energy Charge SLIP 12.19 mills/kWh 9/30/2015 Cost Recovery Charge (CRC) SLIP 0 mills/kWh 9/30/2015 Transmission Service Provided by Current Rates effective10/12 - 9/15 (or until superceded) Rate Schedule Effective Through Firm Point-to-Point Transmission (SP-PTP7) CRSP $1.14 per kW-month $13.69/kW-year $0.00156/kW-hour $0.04/kW-day $0.26/kW-week 10/1/2008-9/30/2015 Network Integration Transmission (SP-NW3) CRSP see rate schedule 10/1/2008-9/30/2015 Non-Firm Point-to-Point Transmission (SP-NFT6) CRSP see rate schedule 10/1/2008-9/30/2015 Ancillary Services Provided by Rate Rate Schedule

203

Heat collector  

DOE Patents (OSTI)

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.

Merrigan, Michael A. (Santa Cruz, NM)

1984-01-01T23:59:59.000Z

204

Heat collector  

DOE Patents (OSTI)

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.

Merrigan, M.A.

1981-06-29T23:59:59.000Z

205

The Exact Renormalisation Group and Approximate Solutions  

E-Print Network (OSTI)

We investigate the structure of Polchinski's formulation of the flow equations for the continuum Wilson effective action. Reinterpretations in terms of I.R. cutoff greens functions are given. A promising non-perturbative approximation scheme is derived by carefully taking the sharp cutoff limit and expanding in `irrelevancy' of operators. We illustrate with two simple models of four dimensional $\\lambda \\varphi^4$ theory: the cactus approximation, and a model incorporating the first irrelevant correction to the renormalized coupling. The qualitative and quantitative behaviour give confidence in a fuller use of this method for obtaining accurate results.

Tim R. Morris

1993-08-12T23:59:59.000Z

206

Acoustically enhanced heat exchange and drying apparatus  

DOE Patents (OSTI)

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

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

1987-07-10T23:59:59.000Z

207

Self-contained passive solar heating system  

SciTech Connect

A self-contained passive solar heating system includes first and second heat pipes, each having a refrigerant medium therein, a condenser portion and an evaporator portion, with the condenser portion of the first heat pipe being coupled to the evaporator portion of the second heat pipe for transferring heat thereto when the pressure within the first heat pipe is greater than the pressure within the second heat pipe. The evaporator portion of the first heat pipe is adapted to be exposed to a source of heat and the condenser portion of the second heat pipe contacts a medium to be heated. A temperature control mechanism may be installed as the coupling between the first and second heat pipes for uncoupling the same when the temperature within the first heat pipe falls below a predetermined temperature. Also, a third heat pipe may be provided having a thermostatic portion operatively connected to the condenser portion of the second heat pipe by a piston means so that changes in pressure within the thermostatic portion occasioned by changes in temperature of the medium to be heated will cause movement of the pistons to vary the size of the condensing portion of the second heat pipe to increase or decrease the rate of heat transfer to the medium.

Maldonado, E.A.; Woods, J.E.

1983-05-10T23:59:59.000Z

208

Energy Basics: Heat Pump Systems  

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

Systems Air-Source Heat Pumps Ductless Mini-Split Heat Pumps Absorption Heat Pumps Geothermal Heat Pumps Supporting Equipment for Heating & Cooling Systems Water Heating Heat...

209

Heat reclaimer  

SciTech Connect

An apparatus for reclaiming heat from the discharge gas from a combustion fuel heating unit, which has: inlet and outlet sections; an expansion section whose circumference gradually increases in the direction of flow, thereby providing an increased area for heat transfer; flow splitter plates which lie within and act in conjunction with the expansion section wall to form flow compartments, which flow splitter plates and expansion section wall have a slope, with respect to the centroidal axis of the flow compartment not exceeding 0.1228, which geometry prevents a separation of the flow from the enclosing walls, thereby increasing heat transfer and maintaining the drafting function; and a reduction section which converges the flow to the outlet section.

Horkey, E.J.

1982-06-29T23:59:59.000Z

210

Cooperative heat transfer and ground coupled storage system  

DOE Patents (OSTI)

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.

Metz, Philip D. (Rocky Point, NY)

1982-01-01T23:59:59.000Z

211

Process Heating  

Science Conference Proceedings (OSTI)

This technical update uses real world examples to discuss applications of electrotechnology in industrial process heating and to highlight some of the emerging technologies in this field. These emerging technologies, when implemented in a plant, will provide significant energy savings as well as increase productivity. The report presents three case studies of successful implementation of two different electric process-heating technologies in three different industries. The case studies show that in some ...

2011-12-07T23:59:59.000Z

212

HEAT EXCHANGER  

DOE Patents (OSTI)

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

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

1962-10-23T23:59:59.000Z

213

Corrosive resistant heat exchanger  

DOE Patents (OSTI)

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.

Richlen, Scott L. (Annandale, VA)

1989-01-01T23:59:59.000Z

214

Symbolic Test Selection Based on Approximate Analysis  

E-Print Network (OSTI)

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

Paris-Sud XI, Université de

215

Approximations to the Distributed Activation Energy Model  

E-Print Network (OSTI)

Approximations to the Distributed Activation Energy Model for Pyrolysis C.P. Please, 1 M.J. Mc, then resubmitted after minor revisions in September 2002. Abstract The Distributed Activation Energy Model (DAEM effective method for estimating kinetic parameters and the distribution of activation energies. Comparison

McGuinness, Mark

216

Nonlinear piecewise polynomial approximation: Theory and Algorithms  

E-Print Network (OSTI)

algorithms for compression and quick rendering of Digital Terrain Elevation Data (DTED) maps and implement by these and further theoretical results, we develop eÃ?cient practical algorithms for compression and quick rendering linear approximation 23 2.3. Slim B-spaces 32 2.4. Skinny B-spaces 42 2.5. Fat B-spaces: The link

Karaivanov, Borislav

217

Nonlinear piecewise polynomial approximation: Theory and Algorithms  

E-Print Network (OSTI)

algorithms for compression and quick rendering of Digital Terrain Elevation Data (DTED) maps and implement results, we develop efficient practical algorithms for compression and quick rendering of Digital Terrain approximation 23 2.3. Slim B-spaces 32 2.4. Skinny B-spaces 42 2.5. Fat B-spaces: The link to Besov spaces 46 2

Karaivanov, Borislav

218

Real-time creased approximate subdivision surfaces  

Science Conference Proceedings (OSTI)

We present an extension of recently developed Loop and Schaefer's approximation of Catmull-Clark surfaces (ACC) for surfaces with creases and corners which are essential for most applications. We discuss the integration of ACC into Valve's Source game ... Keywords: GPU tessellation, geometric modeling, hardware rendering, subdivision surfaces, video games

Denis Kovacs; Jason Mitchell; Shanon Drone; Denis Zorin

2009-02-01T23:59:59.000Z

219

Complete Orders, Categories and Lattices of Approximations  

Science Conference Proceedings (OSTI)

The present article deals with the problem whether and how the bilattice orderings of knowledge ⩽$_k$ and truth ⩽$_t$ might enrich the theory of rough sets. Passing to the chief idea of the paper, we develop a bilattice-theoretic generalisation ... Keywords: *-autonomous category, Chu construction, Nelson lattice, approximation, bilattice, complete partial order, rough set

Marcin Wolski

2006-09-01T23:59:59.000Z

220

UNIFORM SEMICLASSICAL APPROXIMATION IN QUANTUM STATISTICAL MECHANICS.  

SciTech Connect

We present a simple method to deal with caustics in the semiclassical approximation to the partition function of a one-dimensional quantum system. The procedure, which makes use of complex trajectories, is applied to the quartic double-well potential.

De Carvalho, C.A.A.; Cavalcanit, R.M.; Fraga, E.S.; Joras, S.E.

2000-10-23T23:59:59.000Z

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Testing approximations beyond the proton-neutron quasiparticle random phase approximation  

Science Conference Proceedings (OSTI)

In this work we analyze the validity of recently proposed extensions of the Quasiparticle Random Phase Approximation (QRPA). Particularly, we focus our attention on the Fully Renormalized QRPA (FRQRPA). We found that the results of this approximation do not differ from the results of the QRPA. This finding is supported by a detailed comparison between both formalisms, their assumptions and approximations, in the context of realistic calculations.

Civitarese, O.; Mariano, A. [Department of Physics. University of La Plata, C. C. 67 1900 La Plata (Argentina); Hirsch, J. G. [Instituto de Ciencias Nucleares, UNAM, A. P. 70-543, 04510 Mexico City, D. F. (Mexico); Reboiro, M. [Department of Physics. University of La Plata, C. C. 67 1900 La Plata (Argentina); Faculty of Engineering, University of Lomas de Zamora, Km 2 (1836) Lavallol (Argentina)

2007-08-15T23:59:59.000Z

222

Consumer Winter Heating Oil Costs  

Gasoline and Diesel Fuel Update (EIA)

5 5 Notes: Using the Northeast as a regional focus for heating oil, the typical oil-heated household consumes about 680 gallons of oil during the winter, assuming that weather is "normal." The previous three winters were warmer than average and generated below normal consumption rates. Last winter, consumers saw large increases over the very low heating oil prices seen during the winter of 1998-1999 but, outside of the cold period in late January/early February they saw relatively low consumption rates due to generally warm weather. Even without particularly sharp cold weather events this winter, we think consumers are likely to see higher average heating oil prices than were seen last winter. If weather is normal, our projections imply New England heating oil

223

Heat Recovery in Building Envelopes  

SciTech Connect

Infiltration has traditionally been assumed to contribute to the energy load of a building by an amount equal to the product of the infiltration flow rate and the enthalpy difference between inside and outside. Application of such a simple formula may produce an unreasonably high contribution because of heat recovery within the building envelope. Previous laboratory and simulation research has indicated that such heat transfer between the infiltrating air and walls may be substantial. In this study, Computational Fluid Dynamics was used to simulate sensible heat transfer in typical envelope constructions. The results show that the traditional method may over-predict the infiltration energy load by up to 95 percent at low leakage rates. A simplified physical model has been developed and used to predict the infiltration heat recovery based on the Peclet number of the flow and the fraction of the building envelope active in infiltration heat recovery.

Sherman, Max H.; Walker, Iain S.

2001-01-01T23:59:59.000Z

224

Survey of innovative rates, 1991  

SciTech Connect

Current innovative rate data from 135 major utilities throughout the United States were gathered and analyzed. Over 1000 innovative rates that were in use by the utilities in 1990 and 1991 were identified, abstracted and entered into a database. Survey results indicate that over 616 million MWh were sold to the nearly five million customers using the innovative rates offered. From an annual sales perspective, the most widely used rates are demand-side management rates -- rates intended to change customer energy use -- and rates that are market-driven.'' The survey identified 525 demand-side management rates serving our four million customers with reported sales of approximately 520 million MWh. These rates serve over 80% of the total innovative rate customers and account for 84% of the total MWh sales. Also important in terms of MWh sales they represent are market-driven rates, which accounted for sales of 48 million MWh in 1990. Both demand-side management and market-driven rates show a 20% customer growth rate between 1988 and 1990. Other innovative rates examined in the survey included: prepaid service; load retention incentive rates; technology specific rates; and those rates related expressly to non-utility generators -- namely buy-back and standby rates.

White, L.J.; Wakefield, R.A.; McVicker, C.M.

1992-04-01T23:59:59.000Z

225

Survey of innovative rates, 1991  

Science Conference Proceedings (OSTI)

Current innovative rate data from 135 major utilities throughout the United States were gathered and analyzed. Over 1000 innovative rates that were in use by the utilities in 1990 and 1991 were identified, abstracted and entered into a database. Survey results indicate that over 616 million MWh were sold to the nearly five million customers using the innovative rates offered. From an annual sales perspective, the most widely used rates are demand-side management rates -- rates intended to change customer energy use -- and rates that are market-driven.'' The survey identified 525 demand-side management rates serving our four million customers with reported sales of approximately 520 million MWh. These rates serve over 80% of the total innovative rate customers and account for 84% of the total MWh sales. Also important in terms of the MWh sales they represent are market-driven rates, which accounted for sales of 48 million MWh in 1990. Both demand-side management and market-driven rates show a 20% customer growth rate between 1988 and 1990. Other innovative rates examined in the survey included: prepaid service; load retention incentive rates; technology specific rates; and those rates related expressly to non-utility generators -- namely buy-back and standby rates.

White, L.J.; Wakefield, R.A.; McVicker, C.M.

1992-04-01T23:59:59.000Z

226

Demonstration testing and evaluation of in situ soil heating: Management Plan  

Science Conference Proceedings (OSTI)

This document is the Management Plan for US DOE contract entitled, {open_quotes}Demonstration, Testing and Evaluation of In Situ Soil Heating,{close_quotes} Contract No. DE-AC05-93OR22160, IITRI Project No. C06787. In this project IITRI will demonstrate an in situ soil heating technology for the removal of hazardous organic contaminants present in the soil. In situ heating will be accomplished by the application of 60 Hz ac power to the soil. The soil will be heated to a temperature of about 90{degrees}C. This technology is suited for the removal of those organic compounds which have a normal boiling point in the range of 100{degrees} to 210{degrees}C, or else for those which exhibit a pure component vapor pressure of at least 10 mm Hg in the 90{degrees} to 100{degrees}C temperature range. For example, perchloroethylene, dichlorobenzene, trichlorobenzene, etc. may be removed by in situ ac heating. It is planned to demonstrate the technology by heating approximately 400 tons of soil in the K-1070 Classified Burial Ground located at DOE`s K-25 Site located in Oak Ridge, TN. It is estimated that the heating portion of the demonstration will take approximately 3 weeks at an average power input rate of 150 to 175 kW. IITRI expects to spend considerable time in the front end reviewing site characteristics, preparing detail design, developing Health and Safety Plans and other documents needed to obtain regulatory approval for the demonstration, arranging for site sampling, infrastructure development and document preparation. It is anticipated that site activities will begin in approximately 5 to 6 months. This contract was signed on September 30, 1993. IITRI started work on it in October 1993. It is planned to complete the demonstration and submit approved final reports by September 30, 1994. This project has 12 tasks and four major milestones. The major milestones and their planned completion dates are shown.

Dev, H.

1993-12-31T23:59:59.000Z

227

SAMPLE AVERAGE APPROXIMATION METHOD FOR COMPOUND ...  

E-Print Network (OSTI)

Jun 30, 2013 ... The conditions for convergence in mean, almost surely and rate of convergence are estab- ... Other examples include nonlinear utility functions.

228

TAIL BOUNDS FOR STOCHASTIC APPROXIMATION 1. Introduction ...  

E-Print Network (OSTI)

Apr 19, 2013 ... Friedlander and Schmidt [5] link the convergence rate to E ek .... This inequality is too weak, however, to say anything meaningful about the ...

229

Optimal Stochastic Approximation Algorithms for Strongly Convex ...  

E-Print Network (OSTI)

Jul 1, 2010 ... associated with the convergence rates and introducing efficient validation procedure to check the accuracy ...... John Wiley, Hoboken, NJ, 2003.

230

The heat transfer mechanism in aqueous foam flow in a channel  

Science Conference Proceedings (OSTI)

The Heat transfer mechanism in two-phase aqueous foam flow was investigated for developing energy-efficient heat exchangers. Such heat exchangers can provide low consumption of energy resources due to enhanced heat transfer rates. An enhanced heat transfer ... Keywords: aqueous foam flow, heat exchangers, heat transfer

Irena Gabrielaitien?; Jonas Gylys; Rolandas Jonynas; Tadas Ždankus

2011-12-01T23:59:59.000Z

231

Water Heating | OpenEI  

Open Energy Info (EERE)

Water Heating Water Heating Dataset Summary Description Provides total and average household expenditures on energy for water heating in the United States in 2005. Source EIA Date Released September 01st, 2008 (6 years ago) Date Updated January 01st, 2009 (6 years ago) Keywords Energy Expenditures Residential Water Heating Data application/vnd.ms-excel icon 2005_Total.Expenditures.for_.Water_.Heating_EIA.Sep_.2008.xls (xls, 70.1 KiB) application/vnd.ms-excel icon 2005_Avg.Expenditures.for_.Water_.Heating_EIA.Sep_.2008.xls (xls, 69.1 KiB) Quality Metrics Level of Review Some Review Comment Temporal and Spatial Coverage Frequency Time Period 2005 License License Other or unspecified, see optional comment below Comment Rate this dataset Usefulness of the metadata Average vote Your vote

232

Approximating stochastic volatility by recombinant trees  

E-Print Network (OSTI)

A general method to construct recombinant tree approximations for stochastic volatility models is developed and applied to the Heston model for stock price dynamics. In this application, the resulting approximation is a four tuple Markov process. The ?first two components are related to the stock and volatility processes and take values in a two dimensional Binomial tree. The other two components of the Markov process are the increments of random walks with simple values in {-1; +1}. The resulting effi?cient option pricing equations are numerically implemented for general American and European options including the standard put and calls, barrier, lookback and Asian type pay-o?ffs. The weak and extended weak convergence are also proved.

Akyildirim, Erdinc; Soner, H Mete

2012-01-01T23:59:59.000Z

233

Approximate gauge symmetry of composite vector bosons  

SciTech Connect

It can be shown in a solvable field theory model that the couplings of the composite vector bosons made of a fermion pair approach the gauge couplings in the limit of strong binding. Although this phenomenon may appear accidental and special to the vector bosons made of a fermion pair, we extend it to the case of bosons being constituents and find that the same phenomenon occurs in a more intriguing way. The functional formalism not only facilitates computation but also provides us with a better insight into the generating mechanism of approximate gauge symmetry, in particular, how the strong binding and global current conservation conspire to generate such an approximate symmetry. Remarks are made on its possible relevance or irrelevance to electroweak and higher symmetries.

Suzuki, Mahiko [Lawrence Berkeley National Laboratory and Department of Physics, University of California, Berkeley, California 94720 (United States)

2010-08-15T23:59:59.000Z

234

Approximate gauge symemtry of composite vector bosons  

SciTech Connect

It can be shown in a solvable field theory model that the couplings of the composite vector mesons made of a fermion pair approach the gauge couplings in the limit of strong binding. Although this phenomenon may appear accidental and special to the vector bosons made of a fermion pair, we extend it to the case of bosons being constituents and find that the same phenomenon occurs in more an intriguing way. The functional formalism not only facilitates computation but also provides us with a better insight into the generating mechanism of approximate gauge symmetry, in particular, how the strong binding and global current conservation conspire to generate such an approximate symmetry. Remarks are made on its possible relevance or irrelevance to electroweak and higher symmetries.

Suzuki, Mahiko

2010-06-01T23:59:59.000Z

235

Dictionary Approximation For Matching Pursuit Video Coding  

E-Print Network (OSTI)

Previously, we demonstrated an efficient video codec based on overcomplete signal decomposition using matching pursuits. Dictionary design is an important issue for this system, and others have shown alternate dictionaries which lead to either coding efficiency improvements or reduced encoder complexity. In this work, we introduce for the first time a design methodology which incorporates both coding efficiency and complexity in a systematic way. The key to our new method is an algorithm which takes an arbitrary 2-D dictionary and generates approximations of the dictionary which have fast 2-stage implementations. By varying the quality of the approximation, we can explore a systematic tradeoff between the coding efficiency and complexity of the matching pursuit video encoder. As a practical result, we show cases where complexity is reduced by a factor of 500 to 1000 in exchange for small coding efficiency losses of around 0.1 dB PSNR. 1. INTRODUCTION Most video codecs in use today ar...

Ralph Neff; Avideh Zakhor

2000-01-01T23:59:59.000Z

236

Heat pipe turbine vane cooling  

SciTech Connect

The applicability of using heat pipe principles to cool gas turbine vanes is addressed in this beginning program. This innovative concept involves fitting out the vane interior as a heat pipe and extending the vane into an adjacent heat sink, thus transferring the vane incident heat transfer through the heat pipe to heat sink. This design provides an extremely high heat transfer rate and a uniform temperature along the vane due to the internal change of phase of the heat pipe working fluid. Furthermore, this technology can also eliminate hot spots at the vane leading and trailing edges and increase the vane life by preventing thermal fatigue cracking. There is also the possibility of requiring no bleed air from the compressor, and therefore eliminating engine performance losses resulting from the diversion of compressor discharge air. Significant improvement in gas turbine performance can be achieved by using heat pipe technology in place of conventional air cooled vanes. A detailed numerical analysis of a heat pipe vane will be made and an experimental model will be designed in the first year of this new program.

Langston, L.; Faghri, A. [Connecticut Univ., Storrs, CT (United States). Dept. of Mechanical Engineering

1995-12-31T23:59:59.000Z

237

Rates and Repayment Services  

NLE Websites -- All DOE Office Websites (Extended Search)

Tariff Rates FY 2014 Rates and Rate Schedules FY 2013 Rates and Rate Schedules FY 2012 Rates and Rate Schedules FY 2011 Rates and Rate Schedules FY 2010 Rates and Rate Schedules FY...

238

HEAT GENERATION  

DOE Patents (OSTI)

Heat is generated by the utilization of high energy neutrons produced as by nuclear reactions between hydrogen isotopes in a blanket zone containing lithium, a neutron moderator, and uranium and/or thorium effective to achieve multtplicatton of the high energy neutron. The rnultiplied and moderated neutrons produced react further with lithium-6 to produce tritium in the blanket. Thermal neutron fissionable materials are also produced and consumed in situ in the blanket zone. The heat produced by the aggregate of the various nuclear reactions is then withdrawn from the blanket zone to be used or otherwise disposed externally. (AEC)

Imhoff, D.H.; Harker, W.H.

1963-12-01T23:59:59.000Z

239

Local Linear Convergence of Approximate Projections onto Regularized Sets  

E-Print Network (OSTI)

The numerical properties of algorithms for finding the intersection of sets depend to some extent on the regularity of the sets, but even more importantly on the regularity of the intersection. The alternating projection algorithm of von Neumann has been shown to converge locally at a linear rate dependent on the regularity modulus of the intersection. In many applications, however, the sets in question come from inexact measurements that are matched to idealized models. It is unlikely that any such problems in applications will enjoy metrically regular intersection, let alone set intersection. We explore a regularization strategy that generates an intersection with the desired regularity properties. The regularization, however, can lead to a significant increase in computational complexity. In a further refinement, we investigate and prove linear convergence of an approximate alternating projection algorithm. The analysis provides a regularization strategy that fits naturally with many ill-posed inverse problems, and a mathematically sound stopping criterion for extrapolated, approximate algorithms. The theory is demonstrated on the phase retrieval problem with experimental data. The conventional early termination applied in practice to unregularized, consistent problems in diffraction imaging can be justified fully in the framework of this analysis providing, for the first time, proof of convergence of alternating approximate projections for finite dimensional, consistent phase retrieval problems.

D. Russell Luke

2011-08-10T23:59:59.000Z

240

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

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

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

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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

242

Validation Analysis of Mirror Descent Stochastic Approximation ...  

E-Print Network (OSTI)

utility and conditional value at risk approaches for the asset allocation problem. A discussion ..... zero, with increase of the sample size N, at a rate of O(N. ?1/2. ).

243

Polynomial Approximations for Continuous Linear Programs  

E-Print Network (OSTI)

v ? Rd+1, where Pd denotes the truncation operator that maps ?(t) to ?d(t). In ...... example problem at hand since the capacity constraints couple the output rates.

244

Quantum Calisthenics: Gaussians, The Path Integral and Guided Numerical Approximations  

SciTech Connect

It is apparent to anyone who thinks about it that, to a large degree, the basic concepts of Newtonian physics are quite intuitive, but quantum mechanics is not. My purpose in this talk is to introduce you to a new, much more intuitive way to understand how quantum mechanics works. I begin with an incredibly easy way to derive the time evolution of a Gaussian wave-packet for the case free and harmonic motion without any need to know the eigenstates of the Hamiltonian. This discussion is completely analytic and I will later use it to relate the solution for the behavior of the Gaussian packet to the Feynman path-integral and stationary phase approximation. It will be clear that using the information about the evolution of the Gaussian in this way goes far beyond what the stationary phase approximation tells us. Next, I introduce the concept of the bucket brigade approach to dealing with problems that cannot be handled totally analytically. This approach combines the intuition obtained in the initial discussion, as well as the intuition obtained from the path-integral, with simple numerical tools. My goal is to show that, for any specific process, there is a simple Hilbert space interpretation of the stationary phase approximation. I will then argue that, from the point of view of numerical approximations, the trajectory obtained from my generalization of the stationary phase approximation specifies that subspace of the full Hilbert space that is needed to compute the time evolution of the particular state under the full Hamiltonian. The prescription I will give is totally non-perturbative and we will see, by the grace of Maple animations computed for the case of the anharmonic oscillator Hamiltonian, that this approach allows surprisingly accurate computations to be performed with very little work. I think of this approach to the path-integral as defining what I call a guided numerical approximation scheme. After the discussion of the anharmonic oscillator I will turn to tunneling problems and show that the instanton can also be though of in the same way. I will do this for the classic problem of a double well potential in the extreme limit when the splitting between the two lowest levels is extremely small and the tunneling rate from one well to another is also very small.

Weinstein, Marvin; /SLAC

2009-02-12T23:59:59.000Z

245

Heat reclaimer  

Science Conference Proceedings (OSTI)

A heat reclaimer for the exhaust flue of a heating unit comprises a housing having an air input space, an air output space, and an exhaust space, with a plurality of tubes connected between and communicating the air input space with the air output space and extending through the exhaust space. The exhaust flue of the heating unit is connected into the exhaust space of the housing and an exhaust output is connected to the housing extending from the exhaust space for venting exhaust coming from the heater into the exhaust space to a chimney, for example. A float or level switch is connected to the housing near the bottom of the exhaust space for switching, for example, an alarm if water accumulates in the exhaust space from condensed water vapor in the exhaust. At least one hole is also provided in the housing above the level of the float switch to permit condensed water to leave the exhaust space. The hole is provided in case the float switch clogs with soot. A wiping device may also be provided in the exhaust space for wiping the exterior surfaces of the tubes and removing films of water and soot which might accumulate thereon and reduce their heat transfer capacity.

Bellaff, L.

1981-10-20T23:59:59.000Z

246

Optimal control of the heat equation in an inhomogeneous body  

Science Conference Proceedings (OSTI)

In this paper we consider a heat flow in an inhomogeneous body without internal source. There exists special initial and boundary conditions in this system and we intend to find a convenient coefficient of heat conduction for this body so that body cool ... Keywords: approximation theory, heat equation, linear programming, measure theory

A. H. Borzabadi; A. V. Kamyad; M. H. Farahi

2004-05-01T23:59:59.000Z

247

Energy Basics: Absorption Heat Pumps  

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

Systems Air-Source Heat Pumps Ductless Mini-Split Heat Pumps Absorption Heat Pumps Geothermal Heat Pumps Supporting Equipment for Heating & Cooling Systems Water Heating...

248

Energy Basics: Geothermal Heat Pumps  

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

Systems Air-Source Heat Pumps Ductless Mini-Split Heat Pumps Absorption Heat Pumps Geothermal Heat Pumps Supporting Equipment for Heating & Cooling Systems Water Heating...

249

Shear viscosity in the postquasistatic approximation  

Science Conference Proceedings (OSTI)

We apply the postquasistatic approximation, an iterative method for the evolution of self-gravitating spheres of matter, to study the evolution of anisotropic nonadiabatic radiating and dissipative distributions in general relativity. Dissipation is described by viscosity and free-streaming radiation, assuming an equation of state to model anisotropy induced by the shear viscosity. We match the interior solution, in noncomoving coordinates, with the Vaidya exterior solution. Two simple models are presented, based on the Schwarzschild and Tolman VI solutions, in the nonadiabatic and adiabatic limit. In both cases, the eventual collapse or expansion of the distribution is mainly controlled by the anisotropy induced by the viscosity.

Peralta, C.; Rosales, L.; Rodriguez-Mueller, B.; Barreto, W. [Deutscher Wetterdienst, Frankfurter Str. 135, 63067 Offenbach (Germany); Laboratorio de Fisica Computacional, Universidad Experimental Politecnica 'Antonio Jose de Sucre', Puerto Ordaz (Venezuela, Bolivarian Republic of); Computational Science Research Center, College of Sciences, San Diego State University, San Diego, California (United States); Centro de Fisica Fundamental, Facultad de Ciencias, Universidad de Los Andes, Merida (Venezuela, Bolivarian Republic of)

2010-05-15T23:59:59.000Z

250

Klamath County YMCA geothermal heating project environmental assessment  

DOE Green Energy (OSTI)

The YMCA Geothermal Heating project proposes to obtain approximately 57% of the total facility energy usage through direct application of the Klamath Falls KGRA. This will be accomplished through the design and construction of a retrofit and injection system for the utilization of an existing 110/sup 0/F geothermal energy source at the project site. The existing 2016 foot well will be outfitted with a turbine pump with variable speed drive. The well head will be enclosed by a 10' x 10' building. The geothermal fluid, pumped at a peak rate of 350 gpm will be transported to the YMCA Facility through 5'' diameter schedule 40 black iron pipe fitted with victaulic couplings for expansion. All underground supply pipes will be equipped with magnesium anodes for galvaic protection and will be insulted with 1'' thick calcium silicate insulation, with two layers of 45 number roofing felt applied with asphaltic compound. All supply lines within the building will be insulated with 1'' fiberglass insulation material with a cloth jacket. The fluids will pass through a heating coil and heat exchanger system to provide heat for the 30,000 square foot YMCA facility as well as for the 90,000 gallon swimming pool. The spent geothermal fluids will then be conveyed through a 4'' black iron return pipe to be returned to an acceptable aquifer through the 1500 foot injection well.

Shreve, J.H. (ed.)

1979-07-10T23:59:59.000Z

251

Applications of the Strong Heat Transformation by Pulse Flow in the Shell and Tube Heat Exchanger  

E-Print Network (OSTI)

This article deals with the heat exchange coefficient varied with pulse frequency in the pulsation tube with different flow forms. The findings show that heat can be exchanged coefficient with the pulse frequency, and it has an optimal frequency. The laminar flow and turbulent flow have approximately the same optimal frequency, i.e., about 8 Hz. When the pulsation source was placed in the upstream and downstream position, the heat transformation was completed dissimilarly. These results are coincident with previous experiments. The article also gives some information on the applications of the heat transformation by pulse flow in the shell and tube heat exchanger.

Chen, Y.; Zhao, J.

2006-01-01T23:59:59.000Z

252

Current developments in oil shale research at the Laramie Energy Research Center. [Review of studies in 4 areas: concurrent gasification and retorting; high pressure retorting; abnormal heating rate of interior of large blocks of oil shale; and in-situ combustion  

DOE Green Energy (OSTI)

Current oil shale research being conducted at the Laramie Energy Research Center is many faceted, and some of the recent developments in these areas are presented. Concurrent gasification and retorting of oil shale where the effects of operating pressure and amounts of oxygen and water injection on quality and quantity of gas and oil produced is being studied. This work has resulted in off gas with heating values varying from 50 to 1,300 Btu/ft/sup 3/ and oil recovery of up to 80 vol percent of Fischer assay. The effects of retorting atmosphere, pressure, and external heating rate are being studied in a high pressure batch retort. Results from this work indicate that a nitrogen atmosphere decreases oil yield slightly while a hydrogen atmosphere increases the oil yield significantly. Large blocks of oil shale are being retorted in a 150-ton aboveground retort to study the abnormal heating rate of the interior of the blocks. This could be caused by an oxidation exotherm similar to that found in limited DTA studies. Some early results from the Rock Springs site 9 in-situ experiment are also presented. This is the fifth in-situ combustion experiment and is being performed in a 40-foot-thick oil shale bed having an average Fischer assay of 23 gallons per ton.

Jacobson, I.A. Jr.; Burwell, E.L.; Harak, A.E.; Long, A.; Wise, R.L.

1976-01-01T23:59:59.000Z

253

Heat Sink Performance Analysis through Numerical Technique  

E-Print Network (OSTI)

The increase in dissipated power per unit area of electronic components sets higher demands on the performance of the heat sink. Also if we continue at our current rate of miniaturisation, laptops and other electronic devices can get heated up tremendously. Hence we require a better heat dissipating system to overcome the excess heat generating problem of using nanoelectronics, which is expected to power the next generation of computers. To handle the excessive and often unpredictable heating up of high performance electronic components like microprocessors, we need to predict the temperature profile of the heat sink used. This also helps us to select the best heat sink for the operating power range of any microprocessor. Understanding the temperature profile of a heat sink and a microprocessor helps us to handle its temperature efficiently for a range of loads. In this work, a method to estimate the normal response of a heat sink to various loads of a microprocessor is explained.

Aravindh, B Sri; Nair, T R Gopalakrishnan

2010-01-01T23:59:59.000Z

254

Management Plan: Demonstration testing and evaluation of in situ soil heating  

Science Conference Proceedings (OSTI)

In this project IITRI will demonstrate an in situ soil heating technology for the removal of hazardous organic contaminants present in the soil. In Situ heating will be accomplished by the application of 60 Hz AC power to the soil. The soil will be heated to a temperature of about 90{degree}C. This technology is suited for the removal of those organic compounds which have a normal boiling point in the range of 100{degree} to 210{degree}C, or else for those which exhibit a pure component vapor pressure of at least 10 mm Hg in the 90{degree} to 100{degree}C temperature range. For example, perchloroethylene, dichlorobenzene, trichlorobenzene, etc. may be removed by in situ AC heating. It is planned to demonstrate the technology by heating approximately 400 tons of soil in the K-1070 Classified Burial Ground located at DOE`s K-25 Site located in Oak Ridge, TN. It is estimated that the heating portion of the demonstration will take approximately 3 weeks at an average power input rate of 150 to 175 kill. IITRI expects to spend considerable time in the front end reviewing site characteristics, preparing detail design, developing Health and Safety Plans and other documents needed to obtain regulatory approval for the demonstration, arranging for site sampling, infrastructure development and document preparation. It is anticipated that site activities will begin in approximately 5 to 6 months. This contract was signed on September 30, 1993. IITRI started work on it in October 1993. It is planned to complete the demonstration and submit approved final reports by September 30, 1994. This project has 12 tasks and four major milestones. The major milestones and their planned completion dates are presented.

Dev, H.

1993-11-01T23:59:59.000Z

255

Analytic approximate radiation effects due to Bremsstrahlung  

SciTech Connect

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

Ben-Zvi I.

2012-02-01T23:59:59.000Z

256

Modulated power-law behaviour in Stirling's approximation  

E-Print Network (OSTI)

DEVELOPMENT OF THFEGENERAL ELECTRIC STIRLING ENGINE GAS HEAT PUMP R. C. Meier, Program Manager, Gas heating and cooling, particu- larly in northern climates. The use of waste heat from the Stirling engine, in conjunction with the inherent high engine efficiency, makes the Stirling/Rankine Heat Activated Heat Pump

Hatton, Les

257

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

E-Print Network (OSTI)

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.

Svend-Age Biehs; Jean-Jacques Greffet

2011-03-11T23:59:59.000Z

258

Heat exchanger containing a component capable of discontinuous movement  

DOE Patents (OSTI)

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

Wilson, D.G.

1993-11-09T23:59:59.000Z

259

Heat exchanger containing a component capable of discontinuous movement  

DOE Patents (OSTI)

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.

Wilson, David G. (Winchester, MA)

1993-01-01T23:59:59.000Z

260

Heat exchanger containing a component capable of discontinuous movement  

DOE Patents (OSTI)

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.

Wilson, David Gordon (Winchester, MA)

2002-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Advanced Heat Pump Water Heating Technology: Testing Commercial and Residential Systems in the Laboratory and Field  

Science Conference Proceedings (OSTI)

Heat pump water heaters (HPWHs) provide electric water heating at a much greater overall efficiency than conventional electric resistance systems. In the residential market, approximately half of all water heaters are electric resistance; these systems can be replaced by HPWHs in most applications with expected savings of 30%–60%. In commercial applications, most systems presently use natural gas or another fuel in direct combustion. Emerging HPWH systems are now able to provide water heating ...

2013-12-20T23:59:59.000Z

262

ABSORPTION HEAT PUMP IN THE DISTRICT HEATING  

E-Print Network (OSTI)

#12;ABSORPTION HEAT PUMP IN THE DISTRICT HEATING PLANT Dr.sc.ing. Agnese Lickrastina M.Sc. Normunds European Heat Pump Summit 2013, Nuremberg, 15-16.10.2013 · Riga District Heating company · Operation #12;JSC RGAS SILTUMS · the biggest District Heating company in Latvia and in the Baltic states

Oak Ridge National Laboratory

263

Heat Exchangers  

Science Conference Proceedings (OSTI)

Table 16   Ceramic heat exchanger systems...Soaking pit 870â??1230 1600â??2250 Fe, Si, alkalis Solar Turbines â?¦ 4â??8 OD Ã? 180 long (440 tubes) Aluminum melt furnaces 1010 1850 Alkali salts Plate fin GTE 0.6, 1.6 25â??46 Multiple 870â??1370 1600â??2250 Clean (good), alkalis (poor) Coors 0.25, 1.0 30 Ã? 30 Ã? 46 Multiple Clean (good), alkalis (poor) Radiant...

264

A Simple Approximate Result for the Maximum Growth Rate of Baroclinic Instabilities  

Science Conference Proceedings (OSTI)

The Charney problem for baroclinic instability involves the quasi-geostrophic instability of a zonal flow on a ? plane where the zonal flow is characterized by a constant vertical shear. The atmosphere is non-Boussinesq and continuous. The ...

R. S. Lindzen; Brian Farrell

1980-07-01T23:59:59.000Z

265

Electrically heated liquid tank employing heat pipe heat transfer means  

SciTech Connect

The heating apparatus for applying heat to the interior of a chamber includes a modular, removable, electrical, heat-producing unit and a heat pipe mountable in a wall of the chamber with one end of the pipe arranged to receive heat from the electrical heat producing unit exterior of the housing and with another end of the pipe constructed and arranged to apply heat to the medium within the chamber. The heat pipe has high conductivity with a low temperature differential between the ends thereof and the heat producing unit includes an electric coil positioned about and removably secured to the one end of the heat pipe. The electric coil is embedded in a high thermal conducitivity, low electrical conductivity filler material which is surrounded by a low thermal conductivity insulating jacket and which is received around a metal core member which is removably secured to the one end of the heat pipe.

Shutt, J.R.

1978-12-26T23:59:59.000Z

266

Solar heat collector  

SciTech Connect

A solar heat collector comprises an evacuated transparent pipe; a solar heat collection plate disposed in the transparent pipe; a heat pipe, disposed in the transparent pipe so as to contact with the solar heat collection plate, and containing an evaporable working liquid therein; a heat medium pipe containing a heat medium to be heated; a heat releasing member extending along the axis of the heat medium pipe and having thin fin portions extending from the axis to the inner surface of the heat medium pipe; and a cylindrical casing surrounding coaxially the heat medium pipe to provide an annular space which communicates with the heat pipe. The evaporable working liquid evaporates, receiving solar heat collected by the heat collection plate. The resultant vapor heats the heat medium through the heat medium pipe and the heat releasing member.

Yamamoto, T.; Imani, K.; Sumida, I.; Tsukamoto, M.; Watahiki, N.

1984-04-03T23:59:59.000Z

267

Optimal Stochastic Approximation Algorithms for Strongly Convex ...  

E-Print Network (OSTI)

optimal rate of convergence for solving strongly convex SCO problems in ... where X is a closed convex set in Euclidean space E, X(x) is a simple convex function with known ..... Note that the notation log has a base of 2 throughout this paper.

268

Geothermal district heating systems  

DOE Green Energy (OSTI)

Ten district heating demonstration projects and their present status are described. The projects are Klamath County YMCA, Susanville District Heating, Klamath Falls District Heating, Reno Salem Plaza Condominium, El Centro Community Center Heating/Cooling, Haakon School and Business District Heating, St. Mary's Hospital, Diamond Ring Ranch, Pagosa Springs District Heating, and Boise District Heating.

Budney, G.S.; Childs, F.

1982-01-01T23:59:59.000Z

269

Semiclassical approximation to supersymmetric quantum gravity  

SciTech Connect

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

Kiefer, Claus; Lueck, Tobias; Moniz, Paulo [Institut fuer Theoretische Physik, Universitaet zu Koeln, Zuelpicher Strasse 77, 50937 Cologne (Germany); Astronomy Unit, School of Mathematical Sciences, Queen Mary College, University of London, Mile End Road, London E1 4NS (United Kingdom)

2005-08-15T23:59:59.000Z

270

Generic sequential sampling for metamodel approximations  

SciTech Connect

Metamodels approximate complex multivariate data sets from simulations and experiments. These data sets often are not based on an explicitly defined function. The resulting metamodel represents a complex system's behavior for subsequent analysis or optimization. Often an exhaustive data search to obtain the data for the metalnodel is impossible, so an intelligent sampling strategy is necessary. While inultiple approaches have been advocated, the majority of these approaches were developed in support of a particular class of metamodel, known as a Kriging. A more generic, cotninonsense approach to this problem allows sequential sampling techniques to be applied to other types of metamodeis. This research compares recent search techniques for Kriging inetamodels with a generic, inulti-criteria approach combined with a new type of B-spline metamodel. This B-spline metamodel is competitive with prior results obtained with a Kriging metamodel. Furthermore, the results of this research highlight several important features necessary for these techniques to be extended to more complex domains.

Turner, C. J. (Cameron J.); Campbell, M. I. (Matthew I.)

2003-01-01T23:59:59.000Z

271

Selenide isotope generator for the Galileo Mission. Axially-grooved heat pipe: accelerated life test results  

SciTech Connect

The results through SIG/Galileo contract close-out of accelerated life testing performed from June 1978 to June 1979 on axially-grooved, copper/water heat pipes are presented. The primary objective of the test was to determine the expected lifetime of axially-grooved copper/water heat pipes. The heat pipe failure rate, due to either a leak or a build-up of non-condensible gas, was determined. The secondary objective of the test was to determine the effects of time and temperature on the thermal performance parameters relevant to long-term (> 50,000 h) operation on a space power generator. The results showed that the gas generation rate appears to be constant with time after an initial sharp rise although there are indications that it drops to approximately zero beyond approx. 2000 h. During the life test, the following pipe-hours were accumulated: 159,000 at 125/sup 0/C, 54,000 at 165/sup 0/C, 48,000 at 185/sup 0/C, and 8500 at 225/sup 0/C. Heated hours per pipe ranged from 1000 to 7500 with an average of 4720. Applying calculated acceleration factors yields the equivalent of 930,000 pipe-h at 125/sup 0/C. Including the accelerated hours on vendor tested pipes raises this number to 1,430,000 pipe-hours at 125/sup 0/C. It was concluded that, for a heat pipe temperature of 125/sup 0/C and a mission time of 50,000 h, the demonstrated heat pipe reliability is between 80% (based on 159,000 actual pipe-h at 125/sup 0/C) and 98% (based on 1,430,000 accelerated pipe-h at 125/sup 0/C). Measurements indicate some degradation of heat transfer with time, but no detectable degradation of heat transport. (LCL)

1979-08-01T23:59:59.000Z

272

Heat pump system  

DOE Patents (OSTI)

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.

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

1982-01-01T23:59:59.000Z

273

Heat pump system  

DOE Patents (OSTI)

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

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

1979-01-01T23:59:59.000Z

274

Energy Basics: Radiant Heating  

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

very low heat capacity and have the quickest response time of any heating technology. More Information Visit the Energy Saver website for more information about radiant heating...

275

Energy Basics: Radiant Heating  

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

low heat capacity and have the quickest response time of any heating technology. More Information Visit the Energy Saver website for more information about radiant heating in homes...

276

Geothermal Energy: Residential Space Heating  

DOE Green Energy (OSTI)

The purpose of this study, which was carried out under the auspices of the DGRST, was to determine the best way to use geothermal hot water for residential space heating. It quickly became apparent that the type of heating apparatus used in the housing units was most important and that heat pumps could be a valuable asset, making it possible to extract even more geothermal heat and thus substantially improve the cost benefit of the systems. Many factors play a significant role in this problem. Therefore, after a first stage devoted to analyzing the problem through a manual method which proved quite useful, the systematic consideration of all important aspects led us to use a computer to optimize solutions and process a large number of cases. The software used for this general study can also be used to work out particular cases: it is now available to any interested party through DGRST. This program makes it possible to: (1) take climatic conditions into account in a very detailed manner, including temperatures as well as insolation. 864 cases corresponding to 36 typical days divided into 24 hours each were chosen to represent the heating season. They make it possible to define the heating needs of any type of housing unit. (2) simulate and analyze the behavior in practice of a geothermal heating system when heat is extracted from the well by a simple heat exchanger. This simulation makes it possible to evaluate the respective qualities of various types of heating apparatus which can be used in homes. It also makes it possible to define the best control systems for the central system and substations and to assess quite accurately the presence of terminal controls, such as radiators with thermostatically controlled valves. (3) determine to what extent the addition of a heat pump makes it possible to improve the cost benefit of geothermal heating. When its average characteristics and heating use conditions (price, coefficient of performance, length of utilization, electrical rates, etc.) are taken into account, the heat pump should not be scaled for maximum heating power. Consequently, the program considers several possible sizes, with different installation schemes, and selects for each case the value which corresponds to the lowest cost of heating.

None

1977-03-01T23:59:59.000Z

277

Rock Hill Utilities - Water Heater and Heat Pump Rebate Program |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Rock Hill Utilities - Water Heater and Heat Pump Rebate Program Rock Hill Utilities - Water Heater and Heat Pump Rebate Program Rock Hill Utilities - Water Heater and Heat Pump Rebate Program < Back Eligibility Residential Savings Category Heating & Cooling Commercial Heating & Cooling Heat Pumps Appliances & Electronics Water Heating Program Info State South Carolina Program Type Utility Rebate Program Rebate Amount Water Heater: up to $275 Heat Pump Replacement: $400 Provider Rock Hill Utilities Through the SmartChoice program, Rock Hill Utilities offers rebates for water heater and heat pump replacements. Information on financing for heat pumps can also be found on the web site listed above. If both the water heater and heat pump are purchased then the customer may qualify for the Great Rate program. The Great Rate program will add a 25% discount to a

278

Rates and Repayment Services  

NLE Websites -- All DOE Office Websites (Extended Search)

Customer Letter - Preliminary Review of Drought Adder Component for 2011 Firm Power Rates 2010 Rates and Rate Schedule - Current * 2009 Rates and Rate Schedule 2008 Rates and...

279

Heat transfer and heat exchangers reference handbook  

Science Conference Proceedings (OSTI)

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

Not Available

1991-01-15T23:59:59.000Z

280

Heating systems for heating subsurface formations  

Science Conference Proceedings (OSTI)

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.

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

2011-04-26T23:59:59.000Z

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Heat exchanger  

DOE Patents (OSTI)

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

Brackenbury, Phillip J. (Richland, WA)

1986-01-01T23:59:59.000Z

282

Table A5. Approximate Heat Content of Coal and Coal Coke, 1949 ...  

U.S. Energy Information Administration (EIA)

This Week in Petroleum › Weekly Petroleum Status Report › Weekly Natural Gas Storage Report ... coal obtained from a refuse bank or slurry dam, anthracite culm,

283

Table A5. Approximate Heat Content of Coal and Coal Coke, 1949 ...  

U.S. Energy Information Administration (EIA)

1 Beginning in 2001, includes a small amount of refuse recovery (coal recaptured from a refuse mine, and cleaned to reduce the concentration of ...

284

Breakdown of the linear approximation in the perturbative analysis of heat conduction in relativistic systems  

E-Print Network (OSTI)

We analyze the effects of thermal conduction in a relativistic fluid just after its departure from spherical symmetry, on a time scale of the order of relaxation time. Using first order perturbation theory, it is shown that, as in spherical systems, at a critical point the effective inertial mass density of a fluid element vanishes and becomes negative beyond that point. The impact of this effect on the reliability of causality conditions is discussed.

L. Herrera; A. Di Prisco; J. Martinez

1998-03-25T23:59:59.000Z

285

Table A4. Approximate Heat Content of Natural Gas, 1949-2011 (Btu ...  

U.S. Energy Information Administration (EIA)

Short-Term Energy Outlook › Annual Energy Outlook ... 1984: 1,109: 1,031: 1,030: 1,035: 1,031: 1,005: 1,010: 1985: 1,112: 1,032: 1,031: 1,038: 1,032: 1,002: 1,011 ...

286

Asymptotic analysis of multiscale approximations to reaction networks  

E-Print Network (OSTI)

A reaction network is a chemical system involving multiple reactions and chemical species. Stochastic models of such networks treat the system as a continuous time Markov chain on the number of molecules of each species with reactions as possible transitions of the chain. In many cases of biological interest some of the chemical species in the network are present in much greater abundance than others and reaction rate constants can vary over several orders of magnitude. We consider approaches to approximation of such models that take the multiscale nature of the system into account. Our primary example is a model of a cell’s viral infection for which we apply a combination of averaging and law of large number arguments to show that the “slow ” component of the model can be approximated by a deterministic equation and to characterize the asymptotic distribution of the “fast ” components. The main goal is to illustrate techniques that can be used to reduce the dimensionality of much more complex models. 1. Stochastic models for reaction networks. A reaction network is a chemical system involving multiple reactions and chemical species. The simplest stochastic model for a network treats the system as a continuous time Markov chain whose state X is a vector giving the number of molecules of each species present with each reaction modeled as a possible transition for the state. The model for the kth reaction is determined by a vector of inputs ?k specifying the number of molecules of each chemical species that are

Karen Ball; Thomas G. Kurtz; Lea Popovic; Greg Rempala

1961-01-01T23:59:59.000Z

287

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

E-Print Network (OSTI)

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. Subject headings: meteors, meteoroids — shock waves — solar system: formation 1

Hitoshi Miura; Taishi Nakamoto

2006-01-01T23:59:59.000Z

288

Comonotonic approximations for optimal portfolio selection problems  

E-Print Network (OSTI)

We investigate multiperiod portfolio selection problems in a Black & Scholes type market where a basket of 1 riskfree and m risky securities are traded continuously. We look for the optimal allocation of wealth within the class of ’constant mix ’ portfolios. First, we consider the portfolio selection problem of a decision maker who invests money at predetermined points in time in order to obtain a target capital at the end of the time period under consideration. A second problem concerns a decision maker who invests some amount of money (the initial wealth or provision) in order to be able to fullfil a series of future consumptions or payment obligations. Several optimality criteria and their interpretation within Yaari’s dual theory of choice under risk are presented. For both selection problems, we propose accurate approximations based on the concept of comonotonicity, as studied in Dhaene, Denuit, Goovaerts, Kaas & Vyncke (2002 a,b). Our analytical approach avoids simulation, and hence reduces the computing effort drastically. 1

J. Dhaene; S. Vanduffel; M. J. Goovaerts; R. Kaas; D. Vyncke

2005-01-01T23:59:59.000Z

289

Climate, extreme heat, and electricity demand in California  

SciTech Connect

Climate projections from three atmosphere-ocean climate models with a range of low to mid-high temperature sensitivity forced by the Intergovernmental Panel for Climate Change SRES higher, middle, and lower emission scenarios indicate that, over the 21st century, extreme heat events for major cities in heavily air-conditioned California will increase rapidly. These increases in temperature extremes are projected to exceed the rate of increase in mean temperature, along with increased variance. Extreme heat is defined here as the 90 percent exceedance probability (T90) of the local warmest summer days under the current climate. The number of extreme heat days in Los Angeles, where T90 is currently 95 F (32 C), may increase from 12 days to as many as 96 days per year by 2100, implying current-day heat wave conditions may last for the entire summer, with earlier onset. Overall, projected increases in extreme heat under the higher A1fi emission scenario by 2070-2099 tend to be 20-30 percent higher than those projected under the lower B1 emission scenario, ranging from approximately double the historical number of days for inland California cities (e.g. Sacramento and Fresno), up to four times for previously temperate coastal cities (e.g. Los Angeles, San Diego). These findings, combined with observed relationships between high temperature and electricity demand for air-conditioned regions, suggest potential shortfalls in transmission and supply during T90 peak electricity demand periods. When the projected extreme heat and peak demand for electricity are mapped onto current availability, maintaining technology and population constant only for demand side calculations, we find the potential for electricity deficits as high as 17 percent. Similar increases in extreme heat days are suggested for other locations across the U.S. southwest, as well as for developing nations with rapidly increasing electricity demands. Electricity response to recent extreme heat events, such as the July 2006 heat wave in California, suggests that peak electricity demand will challenge current supply, as well as future planned supply capacities when population and income growth are taken into account.

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

2008-04-01T23:59:59.000Z

290

ANALYTIC APPROXIMATION OF CARBON CONDENSATION ISSUES IN TYPE II SUPERNOVAE  

SciTech Connect

I present analytic approximations for some issues related to condensation of graphite, TiC, and silicon carbide in oxygen-rich cores of supernovae of Type II. Increased understanding, which mathematical analysis can support, renders researchers more receptive to condensation in O-rich supernova gases. Taking SN 1987A as typical, my first analysis shows why the abundance of CO molecules reaches an early maximum in which free carbon remains more abundant than CO. This analysis clarifies why O-rich gas cannot oxidize C if {sup 56}Co radioactivity is as strong as in SN 1987A. My next analysis shows that the CO abundance could be regarded as being in chemical equilibrium if the CO molecule is given an effective binding energy rather than its laboratory dissociation energy. The effective binding energy makes the thermal dissociation rate of CO equal to its radioactive dissociation rate. This preserves possible relevance for the concept of chemical equilibrium. My next analysis shows that the observed abundances of CO and SiO molecules in SN 1987A rule out frequent suggestions that equilibrium condensation of SUNOCONs has occurred following atomic mixing of the He-burning shell with more central zones in such a way as to reproduce roughly the observed spectrum of isotopes in SUNOCONs while preserving C/O > 1. He atoms admixed along with the excess carbon would destroy CO and SiO molecules, leaving their observed abundances unexplained. The final analysis argues that a chemical quasiequilibrium among grains (but not gas) may exist approximately during condensation, so that its computational use is partially justified as a guide to which mineral phases would be stable against reactions with gas. I illustrate this point with quasiequilibrium calculations by Ebel and Grossman that have shown that graphite is stable even when O/C >1 if prominent molecules are justifiably excluded from the calculation of chemical equilibrium.

Clayton, Donald D., E-mail: claydonald@gmail.com [Department of Physics and Astronomy, Clemson University, Clemson, SC (United States)

2013-01-01T23:59:59.000Z

291

Radiofrequency plasma heating: proceedings  

SciTech Connect

The conference proceedings include sessions on Alfven Wave Heating, ICRF Heating and Current Drive, Lower Hybrid Heating and Current Drive, and ECRF Heating. Questions of confinement, diagnostics, instabilities and technology are considered. Individual papers are cataloged separately. (WRF)

Swenson, D.G. (ed.)

1985-01-01T23:59:59.000Z

292

Photovoltaic roof heat flux  

E-Print Network (OSTI)

and could the heat transfer processes be modeled to estimateindicating that the heat transfer processes were modeled w i

Samady, Mezhgan Frishta

2011-01-01T23:59:59.000Z

293

Testing and analysis of immersed heat exchangers  

DOE Green Energy (OSTI)

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.

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

1986-08-01T23:59:59.000Z

294

Flow over Heated Terrain. Part I: Linear Theory and Idealized Numerical Simulations  

Science Conference Proceedings (OSTI)

The flow past heated topography is examined with both linear and nonlinear models. It is first shown that the forcing of an obstacle with horizontally homogenous surface heating can be approximated by the forcing of an obstacle with surface ...

N. Andrew Crook; Donna F. Tucker

2005-09-01T23:59:59.000Z

295

Heat pipe methanator  

DOE Patents (OSTI)

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

Ranken, William A. (Los Alamos, NM); Kemme, Joseph E. (Los Alamos, NM)

1976-07-27T23:59:59.000Z

296

Heat capacity in weakly correlated liquids  

Science Conference Proceedings (OSTI)

Previously unavailable numerical data related to the heat capacity in two- and three-dimensional liquid Yukawa systems are obtained by means of fluctuation theory. The relations between thermal conductivity and diffusion constants are numerically studied and discussed. New approximation for heat capacity dependence on non-ideality parameter for weakly correlated systems of particles is proposed. Comparison of the obtained results to the existing theoretical and numerical data is discussed.

Khrustalyov, Yu. V.; Vaulina, O. S. [Joint Institute for High Temperatures RAS, 125412, Izhorskaya St., 13 bld.2, Moscow (Russian Federation); Moscow Institute of Physics and Technology, 117303, Kerchenskaya St., 1A bld.1, Moscow (Russian Federation); Koss, X. G. [Joint Institute for High Temperatures RAS, 125412, Izhorskaya St., 13 bld.2, Moscow (Russian Federation)

2012-12-15T23:59:59.000Z

297

Midland, South Dakota geothermal district heating  

SciTech Connect

This article describes historical aspects and present usage of geothermal district heating systems in the town of Midland, South Dakota. The use of geothermal resources exists due to a joint venture between the school district and the city back in the early 1960`s. A total of approximately 30,000 square feet (2800 square meters) of floor space is heated using geothermal energy in Midland. This provides an estimated annual saving in propane cost of $15,000 to the community.

Lund, J.W.

1997-12-01T23:59:59.000Z

298

Jones-Onslow EMC - Residential Heating and Cooling Rebate Program |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Jones-Onslow EMC - Residential Heating and Cooling Rebate Program Jones-Onslow EMC - Residential Heating and Cooling Rebate Program Jones-Onslow EMC - Residential Heating and Cooling Rebate Program < Back Eligibility Residential Savings Category Heating & Cooling Commercial Heating & Cooling Cooling Heat Pumps Program Info State North Carolina Program Type Utility Rebate Program Rebate Amount Central AC (15 SEER or greater): $35 Central AC (16 SEER or greater): $50 Heat Pump (15 SEER or greater): $250 Geothermal Heat Pump (19 EER or greater): $350 Provider Jones-Onslow EMC Jones-Onslow Electric Membership Corporation offers rebates to residential members who install energy efficient heating and cooling equipment. Members can replace an existing central AC or heat pump, which does not have a SEER rating greater than 13, with a central AC, heat pump, or geothermal heat

299

Segmented heat exchanger  

DOE Patents (OSTI)

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.

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

300

Dual source heat pump  

DOE Patents (OSTI)

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.

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

1982-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Heat reclaimer for a heat pump  

Science Conference Proceedings (OSTI)

This invention relates to a heat reclaiming device for a heat pump. The heat reclaimer is able to absorb heat from the compressor by circulating cooling fluid through a circuit which is mounted in good heat transfer relationship with the condenser, then around the shell of the motor-compressor and lastly around the hollow tube which connects the condenser to the compressor. The reclaiming circuit is connected into a fluid circulating loop which is used to supply heat to the evaporator coil of the heat pump.

Beacham, W.H.

1981-02-03T23:59:59.000Z

302

On the Wave Spectrum Generated by Tropical Heating  

Science Conference Proceedings (OSTI)

Convective heating profiles are computed from one month of rainfall rate and cloud-top height measurements using global Tropical Rainfall Measuring Mission and infrared cloud-top products. Estimates of the tropical wave response to this heating ...

David A. Ortland; M. Joan Alexander; Alison W. Grimsdell

2011-09-01T23:59:59.000Z

303

Rates and Repayment Services  

NLE Websites -- All DOE Office Websites (Extended Search)

Rates Loveland Area Project Firm Power Rates Transmission and Ancillary Services Rates 2012 Rate Adjustment-Transmission and Ancillary Services 2010 Rate Adjustment-Firm Power 2009...

304

Rates and Repayment Services  

NLE Websites -- All DOE Office Websites (Extended Search)

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

305

Calculation of tunneling rates across a barrier with continuous potential  

E-Print Network (OSTI)

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

Sina Khorasani

2011-04-10T23:59:59.000Z

306

The Effect of High Cooling Rate and Powder Composition on ...  

Science Conference Proceedings (OSTI)

Coatings were deposited by applying different types of thermal spray systems. Influence of the heating and cooling rates on coating microstructure and ...

307

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

E-Print Network (OSTI)

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

Jordan Hristov

2010-12-12T23:59:59.000Z

308

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

SciTech Connect

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

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

1992-07-01T23:59:59.000Z

309

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

SciTech Connect

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

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

1992-07-01T23:59:59.000Z

310

Novel heat pipe combination  

SciTech Connect

The basic heat pipe principle is employed in a heat pipe combination wherein two heat pipes are combined in opposing relationship to form an integral unit; such that the temperature, heat flow, thermal characteristics, and temperature-related parameters of a monitored environment or object exposed to one end of the heat pipe combination can be measured and controlled by controlling the heat flow of the opposite end of the heat pipe combination.

Arcella, F.G.

1978-01-10T23:59:59.000Z

311

Estimating Historical Heating and Cooling Needs. Per Capita Degree Days  

Science Conference Proceedings (OSTI)

Time series of approximate United States average annual per capita heating and cooling degree days for the years 1895–1983 are presented. The data reflect the combined effects of climate fluctuations and population shifts, and can be used in ...

M. W. Downton; T. R. Stewart; K. A. Miller

1988-01-01T23:59:59.000Z

312

What Determines Meridional Heat Transport in Climate Models?  

Science Conference Proceedings (OSTI)

The annual mean maximum meridional heat transport (MHTMAX) differs by approximately 20% among coupled climate models. The value of MHTMAX can be expressed as the difference between the equator-to-pole contrast in absorbed solar radiation (ASR*) ...

Aaron Donohoe; David S. Battisti

2012-06-01T23:59:59.000Z

313

A desiccant dehumidifier for electric vehicle heating  

DOE Green Energy (OSTI)

Vehicle heating requires a substantial amount of energy. Engines in conventional cars produce enough waste heat to provide comfort heating and defogging/defrosting, even under very extreme conditions. Electric vehicles (EVs), however, generate little waste heat. Using battery energy for heating may consume a substantial fraction of the energy storage capacity, reducing the vehicle range, which is one of the most important parameters in determining EV acceptability. Water vapor generated by the vehicle passengers is in large part responsible for the high heating loads existing in vehicles. In cold climates, the generation of water vapor inside the car may result in water condensation on the windows, diminishing visibility. Two strategies are commonly used to avoid condensation on windows: windows are kept warm, and a large amount of ambient air is introduced in the vehicle. Either strategy results in a substantial heating load. These strategies are often used in combination, and a trade-off exists between them. If window temperature is decreased, ventilation rate has to be increased. Reducing the ventilation rate requires an increase of the temperature of the windows to prevent condensation. An alternative solution is a desiccant dehumidifier, which adsorbs water vapor generated by the passengers. Window temperatures and ventilation rates can then be reduced, resulting in a substantially lower heating load. This paper explores the dehumidifier heating concept. The first part shows the energy savings that could be obtained by using this technology. The second part specifies the required characteristics and dimensions of the system. The results indicate that the desiccant system can reduce the steady-state heating load by 60% or more under typical conditions. The reduction in heating load is such that waste heat may be enough to provide the required heating under most ambient conditions. Desiccant system dimensions and weight appear reasonable for packaging in an EV.

Aceves, S.M.; Smith, J.R.

1996-09-01T23:59:59.000Z

314

A Seasonal Heat Budget across the Extent of the California Current  

Science Conference Proceedings (OSTI)

A seasonal heat budget is based on observations that span the broad California Current (CC) region. Budget terms are estimated from satellite data (oceanic heat advection), repeat ship transects (heat storage rate), and the Comprehensive Ocean–...

Kathleen A. Edwards; Kathryn A. Kelly

2007-03-01T23:59:59.000Z

315

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

E-Print Network (OSTI)

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 ...

Roche, Nicholas Albert

2013-01-01T23:59:59.000Z

316

Confined boiling rates of liquefied petroleum gas on water  

SciTech Connect

Results of a program to measure the rate of boiling of liquefied petroleum gas (LPG) on water surface and to develop an analytical model to describe the phenomena involved are reported. Primary emphasis was placed on liquid propane or LPG mixtures containing small quantities of ethane or butane or both. A few exploratory tests were, however, made with pure liquid ethane, ethylene, and n-butane. The investigation was conducted to provide quantitative data and analytical models to delineate the rate of vaporization, the spread rate and the degree of fractionation, should an LPG tanker suffer an accident leading to a major spill on water. For propane or LPG spills on water, immediately following the contact, violent boiling commenced. Ice quickly formed; in most cases, ice was even thrown onto the sidewalls of the vessel. In some instances sprays of water/ice and propane were ejected from the calorimeter. Within a few seconds, however, the interaction quieted and the surface was covered by a rough ice sheet. The LPG boiled on the surface of this ice, but large gas bubbles occasionally appeared under the ice shield and were trapped. The boiling rate decreased with time with a concomitant increase in the thickness of the ice shield. In the first second or two, very high boiling heat fluxes were experienced. The mass of LPG lost was approximately half that spilled originally. It is estimated that only 5 to 15% could have been ejected as liquid if the water loss is used as a reference. However, since the water surface is very agitated during this period, it is not possible to obtain reliable quantitative values of the boiling flux. Also, as noted, the mass lost in the very early time period was approximately proportional to the original mass of LPG used. It may be inferred that larger spills lead to more mixing and boiling before the ice shield prevents a direct contact between the LPG and the water.

Reid, R.C.; Smith, K.A.

1978-05-01T23:59:59.000Z

317

Relationship between swelling and irradiation creep in cold-worked PCA stainless steel irradiated to {approximately}178 dpa at {approximately}400{degrees}C  

Science Conference Proceedings (OSTI)

The eighth and final irradiation segment for pressurized tubes constructed from the fusion Prime Candidate Alloy (PCA) has been completed in FFTF. At 178 dpa and {approximately}400{degrees}C, the irradiation creep of 20% cold-worked PCA has become dominated by the {open_quotes}creep disappearance{close_quotes} phenomenon. The total diametral deformation rate has reached the limiting value of 0.33%/dpa at the three highest stress levels employed in this test. The stress-enhancement of swelling tends to camouflage the onset of creep disappearance, however, requiring the use of several non-traditional techniques to extract the creep coefficients. No failures occurred in these tubes, even though the swelling ranged from {approximately}20 to {approximately}40%.

Toloczko, M.B. [Univ. of California, Santa Barbara, CA (United States). Dept. of Chemical and Nuclear Engineering; Garner, F.A. [Pacific Northwest Lab., Richland, WA (United States)

1993-09-01T23:59:59.000Z

318

The Radiative Heating in Underexplored Bands Campaigns  

Science Conference Proceedings (OSTI)

Accurately accounting for radiative energy balance between the incoming solar and the outgoing infrared radiative fluxes is very important in modeling the Earth's climate. Water vapor absorption plays a critical role in the radiative heating rate ...

D. D. Turner; E. J. Mlawer

2010-07-01T23:59:59.000Z

319

Mpemba effect, Newton cooling law and heat transfer equation  

E-Print Network (OSTI)

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

Vladan Pankovic; Darko V. Kapor

2010-05-06T23:59:59.000Z

320

A Class of Semi-Lagrangian Approximations for Fluids  

Science Conference Proceedings (OSTI)

This paper discusses a class of finite-difference approximations to the evolution equations of fluid dynamics. These approximations derive from elementary properties of differential forms. Values of a fluid variable ? at any two points of a space-...

Piotr K. Smolarkiewicz; Janusz A. Pudykiewicz

1992-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Four-Stream Isosector Approximation for Solar Radiative Transfer  

Science Conference Proceedings (OSTI)

For radiative transfer in a thin atmosphere, an analytical four-stream isosector approximation for solar radiative transfer is presented. This approximation method is based on the assumption of four spherical sectors of isotropic intensities. ...

J. Li; J. S. Dobbie

1998-02-01T23:59:59.000Z

322

Weak Pressure Gradient Approximation and Its Analytical Solutions  

Science Conference Proceedings (OSTI)

A weak pressure gradient (WPG) approximation is introduced for parameterizing supradomain-scale (SDS) dynamics, and this method is compared to the relaxed form of the weak temperature gradient (WTG) approximation in the context of 3D, linearized, ...

David M. Romps

2012-09-01T23:59:59.000Z

323

Dynamic Enthalpy, Conservative Temperature, and the Seawater Boussinesq Approximation  

Science Conference Proceedings (OSTI)

A new seawater Boussinesq system is introduced, and it is shown that this approximation to the equations of motion of a compressible binary solution has an energy conservation law that is a consistent approximation to the Bernoulli equation of ...

William R. Young

2010-02-01T23:59:59.000Z

324

Multiple source heat pump  

DOE Patents (OSTI)

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.

Ecker, Amir L. (Duncanville, TX)

1983-01-01T23:59:59.000Z

325

Paving materials for heat island mitigation  

NLE Websites -- All DOE Office Websites (Extended Search)

Paving materials for heat island mitigation Paving materials for heat island mitigation Title Paving materials for heat island mitigation Publication Type Report Year of Publication 1997 Authors Pomerantz, Melvin, Hashem Akbari, Allan Chen, Haider Taha, and Arthur H. Rosenfeld Keywords Cool Pavements, Heat Island Abstract This report summarizes paving materials suitable for urban streets, driveways, parking lots and walkways. The authors evaluate materials for their abilities to reflect sunlight, which will reduce their temperatures. This in turn reduces the excess air temperature of cities (the heat island effect). The report presents the compositions of the materials, their suitability for particular applications, and their approximate costs (in 1996). Both new and resurfacing are described. They conclude that, although light-colored materials may be more expensive than conventional black materials, a thin layer of light-colored pavement may produce energy savings and smog reductions whose long-term worth is greater than the extra cost.

326

Empirical Constraints on Proton and Electron Heating in the Fast Solar Wind  

E-Print Network (OSTI)

We analyze measured proton and electron temperatures in the high-speed solar wind in order to calculate the separate rates of heat deposition for protons and electrons. When comparing with other regions of the heliosphere, the fast solar wind has the lowest density and the least frequent Coulomb collisions. This makes the fast wind an optimal testing ground for studies of collisionless kinetic processes associated with the dissipation of plasma turbulence. Data from the Helios and Ulysses plasma instruments were collected to determine mean radial trends in the temperatures and the electron heat conduction flux between 0.29 and 5.4 AU. The derived heating rates apply specifically for these mean plasma properties and not for the full range of measured values around the mean. We found that the protons receive about 60% of the total plasma heating in the inner heliosphere, and that this fraction increases to approximately 80% by the orbit of Jupiter. A major factor affecting the uncertainty in this fraction is th...

Cranmer, Steven R; Breech, Benjamin A; Kasper, Justin C

2009-01-01T23:59:59.000Z

327

Weighted trapezoidal approximation-preserving cores of a fuzzy number  

Science Conference Proceedings (OSTI)

Recently, various researchers have proved that approximations of fuzzy numbers may fail to be fuzzy numbers. In this contribution, we suggest a new weighted trapezoidal approximation of an arbitrary fuzzy number, which preserves its cores. We prove that ... Keywords: Core of fuzzy number, Fuzzy numbers, Trapezoidal fuzzy numbers, Weighted approximation

S. Abbasbandy; T. Hajjari

2010-05-01T23:59:59.000Z

328

Curvilinear parabolic approximation for surface wave transformation with wavecurrent interaction  

E-Print Network (OSTI)

Curvilinear parabolic approximation for surface wave transformation with wave­current interaction not be an appropriate method for the purpose of simplifying the curvilinear parabolic approximation of the vector form of the wave­current equation given by Kirby [Higher-order approximations in the parabolic equation method

Kirby, James T.

329

Rates & Repayment  

NLE Websites -- All DOE Office Websites (Extended Search)

Environmental Review-NEPA Financial Data Operations Planning & Projects Power Marketing Rates Rate Adjustments Transmission Ancillary Services Rates WAPA-137 Rate Order Environmental Review-NEPA Financial Data Operations Planning & Projects Power Marketing Rates Rate Adjustments Transmission Ancillary Services Rates WAPA-137 Rate Order Rates and Repayment Services Rates Current and Historical Rate Information Collbran Power Rates CRSP Power Rates CRSP Transmission System Rates CRSP Management Center interest rates Falcon-Amistad Power Rates Provo River Power Rates Rio Grande Power Rates Seedskadee Power Rates SLCA/IP Power Rates Rate Schedules & Supplemental Rate Information Current Rates for Firm Power, Firm & Non-firm Transmission Service, & Ancillary Services Current Transmission & Ancillary Services Rates Tariffs Components of the SLCA/IP Existing Firm Power Rate Cost Recovery Charge (CRC) Page MOA Concerning the Upper Colorado River Basin

330

Preliminary study of suprathermal alpha particle heating  

SciTech Connect

Some of the consequences of the suprathermal orbits on particle confinement and heating are examined. The guiding-center approximation along with the conservation equations of energy, magnetic moment, and canonical angular momentum were used in the analysis. An example calculation is presented. (MOW)

Miley, G.H.; Petrie, T.W.; Rao, M.P.; Hively, L.H.

1975-01-01T23:59:59.000Z

331

Industrial Waste Heat Recovery Using Heat Pipes  

E-Print Network (OSTI)

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 an estimated energy equivalent of nearly 1.1 million barrels of oil annually. Energy recovered by these units has been used to either preheat process supply air or to heat plant comfort make-up air. Heat pipe heat exchangers have been applied to an ever-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 pipes. This device has a number of advantageous features. Field operational experience of several units in service has been excellent.

Ruch, M. A.

1981-01-01T23:59:59.000Z

332

Effect of Heat Treatment Variations on the Hardness and Mechanical ...  

Science Conference Proceedings (OSTI)

the greatest impact on hardness with increasing cooling rate increasing fully heat treated hardness. A specimen test program was then initiated to determine the ...

333

NBSBR 84-2867 Test Procedures for Rating  

E-Print Network (OSTI)

NBSBR 84-2867 Test Procedures for Rating Residential Heating and Cooling Absorption Equipment U HEATING AND COOLING ABSORPTION EQUIPMENT Brian Weber Reinhard Radermacher David Didion U.S. DEPARTMENT-fired absorption devices operating in either the heating or cooling modes. These procedures are designed to include

Oak Ridge National Laboratory

334

Switching rates of multi-step reactions  

E-Print Network (OSTI)

We consider a switching rate of a meta-stable reaction scheme, which includes reactions with arbitrary steps, e.g. $kA\\to(k+r)A$. Employing WKB approximation, controlled by a large system size, we evaluate both the exponent and the pre-exponential factor for the rate. The results are illustrated on a number of examples.

Escudero, Carlos

2008-01-01T23:59:59.000Z

335

TRANSPARENT HEAT MIRRORS FOR PASSIVE SOLAR HEATING APPLICATIONS  

E-Print Network (OSTI)

for Passive Passive Solar Heating Applications StephenHEAT MIRRORS FOR PASSIVE SOLAR HEATING APPLICATIONS StephenMIRRORS FOR PASSIVE SOLAR HEATING APPLICATIONS Stephen

Selkowitz, S.

2011-01-01T23:59:59.000Z

336

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...

337

Midland District Heating District Heating Low Temperature Geothermal...  

Open Energy Info (EERE)

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

338

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...

339

San Bernardino District Heating District Heating Low Temperature...  

Open Energy Info (EERE)

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

340

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...

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Pagosa Springs District Heating District Heating Low Temperature...  

Open Energy Info (EERE)

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

342

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

Open Energy Info (EERE)

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

343

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

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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...

344

Geothermal Heat Pumps  

Energy.gov (U.S. Department of Energy (DOE))

Geothermal heat pumps use the constant temperature of the earth as an exchange medium for heat. Although many parts of the country experience seasonal temperature extremes—from scorching heat in...

345

Absorption heat pump system  

DOE Patents (OSTI)

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.

Grossman, Gershon (Oak Ridge, TN)

1984-01-01T23:59:59.000Z

346

Absorption heat pump system  

DOE Patents (OSTI)

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.

Grossman, G.

1982-06-16T23:59:59.000Z

347

SMALL PARTICLE HEAT EXCHANGERS  

E-Print Network (OSTI)

ON ~m Small Particle Heat Exchangers Arion J. Hunt June 1978d. LBL 7841 Small Particle Heat Exchangers by Arlon J. Huntgenerally to non-solar heat exchangers. These may be of the

Hunt, A.J.

2011-01-01T23:59:59.000Z

348

Photovoltaic roof heat flux  

E-Print Network (OSTI)

of ~24°C, indicating that heat conduction was small. T h i sday, indicating large heat conduction a n d storage. Control2.1.3 showed that conduction heat flux through the roof was

Samady, Mezhgan Frishta

2011-01-01T23:59:59.000Z

349

Heat Pump Systems  

Energy.gov (U.S. Department of Energy (DOE))

Like a refrigerator, heat pumps use electricity to move heat from a cool space into a warm space, making the cool space cooler and the warm space warmer. Because they move heat rather than generate...

350

Mode Conversion Heating Scenarios for the National Compact Stellarator Experiment  

DOE Green Energy (OSTI)

Radio-frequency heating scenarios for the National Compact Stellarator eXperiment (NCSX) are considered. The focus here is on mode conversion from the fast to the slow ion Bernstein wave as either an electron or ''bulk'' ion heating technique, using a high-field side launch to directly access the ion-ion hybrid layer. Modeling for the planned parameters of NCSX [R(subscript ave) {approximately} 1.4 m, a(subscript ave) {approximately} 0.4 m, B(subscript T)(0) {approximately} 1.2-2 T, n(subscript e)(0) {approximately} 2-5 x 10(superscript19) m(superscript -3), T(subscript e)(0) {approximately} T(subscript i)(0) {approximately} 1-2 keV] for mode conversion in D-H and D-3He plasmas is presented. Possible types of high-field side antennas are also briefly discussed.

Majeski, R.; Wilson, J.R.; and Zarnstorff, M.

2001-05-18T23:59:59.000Z

351

Solar heat collector  

Science Conference Proceedings (OSTI)

A solar heat collector is described that pre-heats water for a household hot water heating system, and also heats the air inside a house. The device includes solar heating panels set into an A-shape, and enclosing an area therein containing a water tank and a wristatic fan that utilize the heat of the enclosed air, and transmit the thermal energy therefrom through a water line and an air line into the house.

Sykes, A.B.

1981-07-28T23:59:59.000Z

352

Woven heat exchanger  

DOE Patents (OSTI)

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.

Piscitella, R.R.

1984-07-16T23:59:59.000Z

353

Description and operation of Haakon School geothermal-heating system  

SciTech Connect

To encourage the development of hydrothermal energy, twenty-three demonstration projects were funded. The Haakon School project is one of twelve such projects. The geothermal direct-use heating system at the Haakon School complex in Philip, South Dakota is described and information gained during approximately three heating seasons of operation is presented.

Childs, F.W.; Kirol, L.D.; Sanders, R.D.; McLatchy, M.J.

1983-10-01T23:59:59.000Z

354

Urban Heat Catastrophes  

NLE Websites -- All DOE Office Websites (Extended Search)

The curve shows the heat index, which reflects the combined effect of temperature and humidity. Last year's Chicago heat wave created a great deal of human discomfort and,...

355

Energy Basics: Heating Systems  

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

of energy sources, including electricity, boilers, solar energy, and wood and pellet-fuel heating. Small Space Heaters Used when the main heating system is inadequate or when...

356

Total Space Heat-  

Gasoline and Diesel Fuel Update (EIA)

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

357

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*...

358

Mass and Heat Recovery  

E-Print Network (OSTI)

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 (air to air heat exchanger). In my papers I use (water to air heat exchanger) 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.

Hindawai, S. M.

2010-01-01T23:59:59.000Z

359

Energy Basics: Water Heating  

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

Storage Water Heaters Tankless Demand Water Heaters Heat Pump Water Heaters Solar Water Heaters Tankless Coil & Indirect Water Heaters Water Heating A variety of...

360

Total Space Heat-  

Gasoline and Diesel Fuel Update (EIA)

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

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

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...

362

Heat Pump for High School Heat Recovery  

E-Print Network (OSTI)

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 has good economic property, can conserve energy and protects the environment. Therefore, there is a large potential for its development. In addition, three projects using this system are presented and contrasted, which indicate that a joint system that uses both the heat pump and heat exchanger to recycle waste heat is a preferable option.

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

2006-01-01T23:59:59.000Z

363

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

E-Print Network (OSTI)

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 counterflow CHE consisting of 3 helical coils. Two separate tests were conducted, one where water was used as heat transfer fluid (HTF) on the coil and shell sides, respectively; while the second one made use of MPCM slurry and water on the coil and shell sides, respectively. The NTU-effectiveness relationship of the CHE when MPCM fluid is used approaches that of a heat exchanger with a heat capacity ratio of zero. The heat transfer results have shown that when using a MPCM slurry, an increase in heat transfer rate can be obtained when compared to heat transfer results obtained using straight heat transfer sections. It has been concluded that the increased specific heat of the slurry as well as the fluid dynamics in helical coil pipes are the main contributors to the increased heat transfer.

Gaskill, Travis

2011-12-01T23:59:59.000Z

364

Geothermal heat pump analysis article  

U.S. Energy Information Administration (EIA)

heat pump transfers heat from the ground or ground water to provide space heating. In the summer, the heat transfer process is reversed; the ground or groundwater

365

SCALE ANALYSIS OF CONVECTIVE MELTING WITH INTERNAL HEAT GENERATION  

SciTech Connect

Using a scale analysis approach, we model phase change (melting) for pure materials which generate internal heat for small Stefan numbers (approximately one). The analysis considers conduction in the solid phase and natural convection, driven by internal heat generation, in the liquid regime. The model is applied for a constant surface temperature boundary condition where the melting temperature is greater than the surface temperature in a cylindrical geometry. We show the time scales in which conduction and convection heat transfer dominate.

John Crepeau

2011-03-01T23:59:59.000Z

366

Effects of particle concentration and surfactant use in convective heat transfer of CuO nanofluids in microchannel flow.  

E-Print Network (OSTI)

??Heat exchange systems used in everything from cars to microelectronics have rapidly advanced in recent years to offer high heat transfer rates in increasingly smaller… (more)

Byrne, Matthew Davidson

2011-01-01T23:59:59.000Z

367

ARM - Measurement - Latent heat flux  

NLE Websites -- All DOE Office Websites (Extended Search)

govMeasurementsLatent heat flux govMeasurementsLatent heat flux ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Latent heat flux The time rate of flow for the specific enthalpy difference between two phases of a substance at the same temperature, typically water. Categories Surface Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments CO2FLX : Carbon Dioxide Flux Measurement Systems ECOR : Eddy Correlation Flux Measurement System EBBR : Energy Balance Bowen Ratio Station

368

ARM - Measurement - Sensible heat flux  

NLE Websites -- All DOE Office Websites (Extended Search)

govMeasurementsSensible heat flux govMeasurementsSensible heat flux ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Sensible heat flux The time rate of flow for the energy transferred from a warm or hot surface to whatever is touching it, typically air. Categories Surface Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments CO2FLX : Carbon Dioxide Flux Measurement Systems ECOR : Eddy Correlation Flux Measurement System EBBR : Energy Balance Bowen Ratio Station

369

Heat Treatment, Microstructure, and Creep Strength of ?/? - TMS  

Science Conference Proceedings (OSTI)

gas flow was used as a cooling medium was made in comparison with the high rate solidification .... of density, heat transfer rate, and high temperature stability. The temperature was measured at ... cross section were encir- cled by the ordered ...

370

Field test of Six-Phase Soil Heating and evaluation of engineering design code  

SciTech Connect

A field test was conducted to evaluate the performance of Six-Phase Soil Heating to enhance the removal of contaminants. The purpose of the test was to determine the scale-up characteristics of the Six-Phase Soil Heating technology and to evaluate a computer process simulator developed for the technology. The test heated a 20-ft diameter cylinder of uncontaminated soil to a 10-ft depth. Six-phase ac power was applied at a rate of 30--35 kW using a power system built from surplus electrical components. The test ran unattended, using a computer-based system to record data, alert staff of any excursions in operating conditions via telephone, and provide automatic shut-off of power depending on the type of excursion. The test data included in situ soil temperatures, voltage profiles, and moisture profiles (using a neutron-probetechnique). After 50 days of heating, soil in the center of the array at the 6-ft depth reached 80[degrees]C. Soil temperatures between the two electrodes at this depth reached approximately 75[degrees]C. Data from this test were compared with those predicted by a computer process simulator. The computer process simulator is a modified version of the TOUGH2 code, a thermal porous media code that can be used to determine the movement of air and moisture in soils. The code was modified to include electrical resistive heating and configured such that an application could be run quickly on a workstation (approximately 5 min for 1 day of field operation). Temperature and soil resistance data predicted from the process simulations matched actual data fairly closely. A series of parametric studies was performed to assess the affect of simulation assumptions on predicted parameters.

Bergsman, T.M.; Roberts, J.S.; Lessor, D.L.; Heath, W.O.

1993-02-01T23:59:59.000Z

371

Field test of Six-Phase Soil Heating and evaluation of engineering design code  

SciTech Connect

A field test was conducted to evaluate the performance of Six-Phase Soil Heating to enhance the removal of contaminants. The purpose of the test was to determine the scale-up characteristics of the Six-Phase Soil Heating technology and to evaluate a computer process simulator developed for the technology. The test heated a 20-ft diameter cylinder of uncontaminated soil to a 10-ft depth. Six-phase ac power was applied at a rate of 30--35 kW using a power system built from surplus electrical components. The test ran unattended, using a computer-based system to record data, alert staff of any excursions in operating conditions via telephone, and provide automatic shut-off of power depending on the type of excursion. The test data included in situ soil temperatures, voltage profiles, and moisture profiles (using a neutron-probetechnique). After 50 days of heating, soil in the center of the array at the 6-ft depth reached 80{degrees}C. Soil temperatures between the two electrodes at this depth reached approximately 75{degrees}C. Data from this test were compared with those predicted by a computer process simulator. The computer process simulator is a modified version of the TOUGH2 code, a thermal porous media code that can be used to determine the movement of air and moisture in soils. The code was modified to include electrical resistive heating and configured such that an application could be run quickly on a workstation (approximately 5 min for 1 day of field operation). Temperature and soil resistance data predicted from the process simulations matched actual data fairly closely. A series of parametric studies was performed to assess the affect of simulation assumptions on predicted parameters.

Bergsman, T.M.; Roberts, J.S.; Lessor, D.L.; Heath, W.O.

1993-02-01T23:59:59.000Z

372

doi:10.1088/0004-637X/702/2/1604 EMPIRICAL CONSTRAINTS ON PROTON AND ELECTRON HEATING IN THE FAST SOLAR WIND  

E-Print Network (OSTI)

We analyze measured proton and electron temperatures in the high-speed solar wind in order to calculate the separate rates of heat deposition for protons and electrons. When comparing with other regions of the heliosphere, the fast solar wind has the lowest density and the least frequent Coulomb collisions. This makes the fast wind an optimal testing ground for studies of collisionless kinetic processes associated with the dissipation of plasma turbulence. Data from the Helios and Ulysses plasma instruments were collected to determine mean radial trends in the temperatures and the electron heat conduction flux between 0.29 and 5.4 AU. The derived heating rates apply specifically for these mean plasma properties and not for the full range of measured values around the mean. We found that the protons receive about 60 % of the total plasma heating in the inner heliosphere, and that this fraction increases to approximately 80 % by the orbit of Jupiter. A major factor affecting the uncertainty in this fraction is the uncertainty in the measured radial gradient of the electron heat conduction flux. The empirically derived partitioning of heat between protons and electrons is in rough agreement with theoretical predictions from a model of linear Vlasov wave damping. For a modeled power spectrum consisting only of Alfvénic fluctuations, the best agreement was found for a distribution of wavenumber vectors that evolves toward isotropy as distance increases. Key words: hydrodynamics – MHD – plasmas – solar wind – turbulence – waves Online-only material: color figures 1.

Steven R. Cranmer; William H. Matthaeus; Benjamin A. Breech; Justin C. Kasper

2009-01-01T23:59:59.000Z

373

Variability of Heat Content in the Central North Pacific in Summer 1987 Determined from Long-Range Acoustic Transmissions  

Science Conference Proceedings (OSTI)

The evolution of the heat content in the central North Pacific Ocean during summer 1987 has been measured using acoustic transmissions between transceivers deployed in a triangle approximately 1000 km on a side. The acoustically determined heat ...

Brian D. Dushaw; Peter F. Worcester; Bruce D. Cornuelle; Bruce M. Howe

1993-12-01T23:59:59.000Z

374

Rotary magnetic heat pump  

DOE Patents (OSTI)

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.

Kirol, Lance D. (Shelly, ID)

1988-01-01T23:59:59.000Z

375

Direct fired heat exchanger  

DOE Patents (OSTI)

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

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

1986-01-01T23:59:59.000Z

376

Woven heat exchanger  

DOE Patents (OSTI)

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.

Piscitella, Roger R. (Idaho Falls, ID)

1987-01-01T23:59:59.000Z

377

Rotary magnetic heat pump  

DOE Patents (OSTI)

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.

Kirol, L.D.

1987-02-11T23:59:59.000Z

378

Heating of trapped ions from the quantum ground state  

E-Print Network (OSTI)

We have investigated motional heating of laser-cooled 9Be+ ions held inradio-frequency (Paul) traps. We have measured heating rates in a variety oftraps with different geometries, electrode materials, and characteristic sizes.The results show that heating is due to electric-field noise from the trapelectrodes which exerts a stochastic fluctuating force on the ion. The scalingof the heating rate with trap size is much stronger than that expected from aspatially uniform noise source on the electrodes (such as Johnson noise fromexternal circuits), indicating that a microscopic uncorrelated noise source onthe electrodes (such as fluctuating patch-potential fields) is a more likelycandidate for the source of heating.

Turchette, Q A; King, B E; Leibfried, D; Meekhof, D M; Myatt, C J; Rowe, M A; Sackett, C A; Wood, C S; Itano, W M; Monroe, C; Wineland, D J

2000-01-01T23:59:59.000Z

379

Heat recovery in building envelopes  

SciTech Connect

Infiltration has traditionally been assumed to contribute to the energy load of a building by an amount equal to the product of the infiltration flow rate and the enthalpy difference between inside and outside. Some studies have indicated that application of such a simple formula may produce an unreasonably high contribution because of heat recovery within the building envelope. The major objective of this study was to provide an improved prediction of the energy load due to infiltration by introducing a correction factor that multiplies the expression for the conventional load. This paper discusses simplified analytical modeling and CFD simulations that examine infiltration heat recovery (IHR) in an attempt to quantify the magnitude of this effect for typical building envelopes. For comparison, we will also briefly examine the results of some full-scale field measurements of IHR based on infiltration rates and energy use in real buildings. The results of this work showed that for houses with insulated walls the heat recovery is negligible due to the small fraction of the envelope that participates in heat exchange with the infiltrating air. However; there is the potential for IHR to have a significant effect for higher participation dynamic walls/ceilings or uninsulated walls. This result implies that the existing methods for evaluating infiltration related building loads provide adequate results for typical buildings.

Walker, Iain S.; Sherman, Max H.

2003-08-01T23:59:59.000Z

380

An Approximation Algorithm for Computing a Parsimonious ... - CECM  

E-Print Network (OSTI)

Due to the large number of species in the real data set ? 6808 fungal gene trees from 23 species ? we applied only our approximation algorithm. We observed.

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Finding approximately rank-one submatrices with the nuclear norm ...  

E-Print Network (OSTI)

Nov 8, 2010 ... Abstract: We propose a convex optimization formulation with the nuclear norm and $\\ell_1$-norm to find a large approximately rank-one ...

382

Hardness and Approximation Results for Lp–Ball Constrained ...  

E-Print Network (OSTI)

Oct 31, 2012... a fundamental research issue is to determine their approximability. ...... R. Saigal, and L. Vandenberghe, editors, Handbook of Semidefinite ...

383

Polynomial time algorithms to approximate mixed volumes within a ...  

E-Print Network (OSTI)

Apr 11, 2007 ... ellipsoid method and a randomized poly-time time algorithm for the approximation of the volume of a convex set. ? gurvits@lanl.gov.

384

AN OPTIMIZED TWO-CAPACITY ADVANCED ELECTRIC HEAT PUMP S. E. Veyo, Manager, Heat Exchange Systems Research  

E-Print Network (OSTI)

exchanger, comfort. #12;AN OPTIMIZED TWO-CAPACITY ADVANCED ELECTRIC HEAT PUMP S. E. Veyo* ABSTRACT A two constrained optimization procedure was used to select heat exchanger proportions, air flow rates National Laboratory. * S. E. Veyo, Mgr., Heat Exchange Systems, Westinghouse R&D Center, Pittsburgh, PA

Oak Ridge National Laboratory

385

Water Heating Products and Services | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Water Heating Products and Services Water Heating Products and Services Water Heating Products and Services May 29, 2012 - 7:04pm Addthis Choosing an efficient water heater will help you save money and Energy. | Photo Credit Energy Department Choosing an efficient water heater will help you save money and Energy. | Photo Credit Energy Department Use the following links to get product information and locate professional services for water heating. Product Information Solar Pool Heating Systems Florida Solar Energy Center Listing of solar pool heating systems evaluated by the Florida Solar Energy Center. Certified Solar Collectors and Systems Solar Rating and Certification Corporation Information on solar collectors and pool heating systems certified under the various Solar Rating and Certification Corporation's rating programs.

386

Water Heating Products and Services | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Water Heating Products and Services Water Heating Products and Services Water Heating Products and Services May 29, 2012 - 7:04pm Addthis Choosing an efficient water heater will help you save money and Energy. | Photo Credit Energy Department Choosing an efficient water heater will help you save money and Energy. | Photo Credit Energy Department Use the following links to get product information and locate professional services for water heating. Product Information Solar Pool Heating Systems Florida Solar Energy Center Listing of solar pool heating systems evaluated by the Florida Solar Energy Center. Certified Solar Collectors and Systems Solar Rating and Certification Corporation Information on solar collectors and pool heating systems certified under the various Solar Rating and Certification Corporation's rating programs.

387

Thulium-170 heat source  

SciTech Connect

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.

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

1990-09-06T23:59:59.000Z

388

Thulium-170 heat source  

DOE Patents (OSTI)

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.

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

1992-01-01T23:59:59.000Z

389

Subsurface heaters with low sulfidation rates  

SciTech Connect

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.

John, Randy Carl; Vinegar, Harold J

2013-12-10T23:59:59.000Z

390

Isothermal heat measurements of TBP-nitric acid solutions  

Science Conference Proceedings (OSTI)

Net heats of reaction were measured in an isothermal calorimeter for both single phase (organic) and two phase (organic and aqueous) TBP/HNO{sub 3} reacting solutions at temperatures above 100 C. The oxidation rate constant was determined to be 5.4E-4 min{sup {minus}1} at 110 C for an open ``vented`` system as compared to 1.33 E-3 min{sup {minus}1} in the closed system. The heat released per unit material oxidized was also reduced. The oxidation in both phases was found to be first order in nitric acid and pseudo-zero order in butylnitrate and water. The hydrolysis (esterification) rate constant determined by Nichols` (1.33E-3 min{sup {minus}1}) fit the experimental data from this work well. Forced evaporation of the volatile components by the product gases from oxidation resulted in a cooling mechanism which more than balanced the heat from the oxidation reaction in the two-phased systems. Rate expressions were derived and rate constants determined for both the single and two phase systems. An approximating mathematical model was developed to fit the experimental data and to extrapolate beyond the experimental conditions. This model shows that one foot of ``reacting`` 14.3M HNO{sub 3} aqueous phase solution at 121 C will transport sufficient water to the organic phase to replace evaporative losses, maintaining endothermicity, for organic layers up to 12.2 + 6.0 feet deep. If the pressure in a reacting system is allowed to increase due to insufficient venting the temperature of the organic phase would increase in temperature to reach a new equilibrium. The rate of oxidation would increase not only due to the increase in temperature but also from the increased concentration of dissolved HNO{sub 3} reduction products. Another important factor is that the cooling system described in this work becomes less effective as the total pressure increases. These factors probably contributed to the explosion at Tomsk.

Smith, J.R.; Cavin, W.S.

1994-12-16T23:59:59.000Z

391

Information filtering via biased heat conduction  

E-Print Network (OSTI)

Heat conduction process has recently found its application in personalized recommendation [T. Zhou \\emph{et al.}, PNAS 107, 4511 (2010)], which is of high diversity but low accuracy. By decreasing the temperatures of small-degree objects, we present an improved algorithm, called biased heat conduction (BHC), which could simultaneously enhance the accuracy and diversity. Extensive experimental analyses demonstrate that the accuracy on MovieLens, Netflix and Delicious datasets could be improved by 43.5%, 55.4% and 19.2% compared with the standard heat conduction algorithm, and the diversity is also increased or approximately unchanged. Further statistical analyses suggest that the present algorithm could simultaneously identify users' mainstream and special tastes, resulting in better performance than the standard heat conduction algorithm. This work provides a creditable way for highly efficient information filtering.

Liu, Jian-Guo; Guo, Qiang

2011-01-01T23:59:59.000Z

392

Temperature and heating rate of ion crystals in Penning traps  

Science Conference Proceedings (OSTI)

... plasma energy (the sum of the potential and kinetic energies) per ion ... That is, the energy increase of an ion, after the cooling ... [15] A. Sørensen and K ...

2004-09-20T23:59:59.000Z

393

Coal plasticity at high heating rates and temperatures  

SciTech Connect

Effects of coal type on coal plasticity are investigated. Seven coals, from the Argonne premium sample bank ranging from lignite to low volatile bituminous, are studied. Different indices and structural data of a coal are shown to affect its plastic behavior. A coal-specific parameter incorporating the effects of labile bridges, oxygen, and hydrogen on plasticity has been used to successfully correlate measured values of maximum plasticity (i.e. minimum apparent viscosity) at elevated temperature with coal type.

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

1992-01-01T23:59:59.000Z

394

Effect of Cooling Rate From Solution Heat Treatment on Waspaloy ...  

Science Conference Proceedings (OSTI)

the oil quench commonly specified to achieve high mechanical strengths. ... precipitation temperature range of 982 through 760°C. Oil quench data from ...

395

The NIST 3 Megawatt Quantitative Heat Release Rate Facility  

Science Conference Proceedings (OSTI)

... A pair of disposable flat disk filters is used to ... is a constant if the speeds of the roof and control ... generated pulse shapes such as a flatter top section ...

2004-07-14T23:59:59.000Z

396

Atmospheric Solar Heating Rate in the Water Vapor Bands  

Science Conference Proceedings (OSTI)

The total absorption of solar radiation by water vapor in clear atmosphere is parameterized as a simple function of the scaled water vapor amount. For applications to cloudy and hazy atmospheres, the flux-weighted k-distribution functions are ...

Ming-Dah Chou

1986-11-01T23:59:59.000Z

397

Measurement and Mapping of Pulse Combustion Impingement Heat Transfer Rates .  

E-Print Network (OSTI)

??Current research shows that pulse combustion impingement drying is an improvement over the steady impingement drying currently in commercial use. Pulse combustion impingement has higher… (more)

Hagadorn, Charles C., III

2005-01-01T23:59:59.000Z

398

Comparison of natural convection heat exchangers for solar water heating systems  

DOE Green Energy (OSTI)

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

Davidson, J.; Liu, W.

1998-09-15T23:59:59.000Z

399

Evaluation and design of downhole heat exchangers for direct application; Annual report, May 1, 1976 - July 1, 1977  

DOE Green Energy (OSTI)

Progress in an experimental and analytical research program to evaluate and improve the design of downhole heat exchangers (DHEs) for direct applications of geothermal energy is reported. Significant progress has been achieved in characterizing flows in wells and without perforated casings and DHEs installed, determination of energy extraction rates for conventional DHEs in both cased and uncased wells, and utilization of information obtained to develop and substantiate models of heat transfer within the well. Flow characterization was obtained by experimentally measuring temperature and velocity profiles. In uncased wells, there was a relatively large vertical temperature gradient (approximately 0.5{sup 0}C/m) and insignificant measured vertical flow, while for the same wells when cased the temperature gradient was essentially zero (approximately 0.03{sup 0}C/m) and a large vertically upward flow was measured (9 to 14 cm/s as measured with a hot-film anemometer). These show that a significant connection cell is established after installation of the casing. The energy extraction rates for a conventional DHE both before and after casing of a 60 m deep well was experimentally measured. In the uncased well up to 300 kW was obtained while the cased well produced over 500 kW. Analytical heat transfer models were developed for the cased well both with and without DHEs. For the cased well without a DHE, the model predicts flow rates that agree with the measured value within about 30 percent. Further, the energy extraction rates predicted by the models agree even better with the measured values. These models allow the energy extraction rates of design parameter variations to be evaluated. At this stage, only trends can be shown but with additional substantiation they should produce optimum energy extraction designs.

Culver, G.G.; Reistad, G.M.

1977-07-01T23:59:59.000Z

400

Heat pipe system  

SciTech Connect

A heat pipe diode device for transferring heat from a heat source component to a heat sink wall is described. It contains a heat pipe body member attached to the best source; the heat source having a wall forming at least a portion of the normal evaporator section of the heat pipe diode; a working fluid within the body member; a cover for the heat pipe diode forming at least a portion of the heat sink wall; the cover forming the normal condenser for the heat pipe diode; a wick connected between the condenser and the evaporator of the heat pipe diode; means for retaining the wick adjacent the heat pipe wall; a wick support plate adjacent to the cover; the wick being attached to the support plate; means for holding the wick in contact with the cover; and means, responsive to excessive temperatures at the heat sink wall, for moving the support plate and a portion of the wick away from the cover to thereby substantially reduce heat flow in the reverse direction through said heat pipe diode device.

Kroebig, H.L.; Riha, F.J. III

1974-12-03T23:59:59.000Z

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Heat conduction in 2D strongly-coupled dusty plasmas  

E-Print Network (OSTI)

We perform non-equilibrium simulations to study heat conduction in two-dimensional strongly coupled dusty plasmas. Temperature gradients are established by heating one part of the otherwise equilibrium system to a higher temperature. Heat conductivity is measured directly from the stationary temperature profile and heat flux. Particular attention is paid to the influence of damping effect on the heat conduction. It is found that the heat conductivity increases with the decrease of the damping rate, while its magnitude confirms previous experimental measurement.

Hou, Lu-Jing

2008-01-01T23:59:59.000Z

402

Neutron imaging of alkali metal heat pipes  

Science Conference Proceedings (OSTI)

High-temperature heat pipes are two-phase, capillary driven heat transfer devices capable of passively providing high thermal fluxes. Such a device using a liquid-metal coolant can be used as a solution for successful thermal management on hypersonic flight vehicles. Imaging of the liquid-metal coolant inside will provide valuable information in characterizing the detailed heat and mass transport. Neutron imaging possesses an inherent advantage from the fact that neutrons penetrate the heat pipe metal walls with very little attenuation, but are significantly attenuated by the liquid metal contained inside. Using the BT-2 beam line at the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland, preliminary efforts have been conducted on a nickel-sodium heat pipe. The contrast between the attenuated beam and the background is calculated to be approximately 3%. This low contrast requires sacrifice in spatial or temporal resolution so efforts have since been concentrated on lithium (Li) which has a substantially larger neutron attenuation cross section. Using the CG-1D beam line at the High Flux Isotope Reactor (HFIR) of Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee, the first neutron images of high-temperature molybdenum (Mo)-Li heat pipes have been achieved. The relatively high neutron cross section of Li allows for the visualization of the Li working fluid inside the heat pipes. The evaporator region of a gravity assisted cylindrical heat pipe prototype 25 cm long was imaged from start-up to steady state operation up to approximately 900 C. In each corner of the square bore inside, the capillary action raises the Li meniscus above the bulk Li pool in the evaporator region. As the operational temperature changes, the meniscus shapes and the bulk meniscus height also changes. Furthermore, a three-dimensional tomographic image is also reconstructed from the total of 128 projection images taken 1.4o apart in which the Li had already cooled and solidified.

Kihm, Ken [University of Tennessee, Knoxville (UTK); Kirchoff, Eric [University of Tennessee, Knoxville (UTK); Golden, Matt [University of Tennessee, Knoxville (UTK); Rosenfeld, J. [Thermacore Inc.; Rawal, S. [Lockheed Martin Space Systems Company; Pratt, D. [United States Air Force Research Laboratory, Wright-Patterson Air Force Base; Bilheux, Hassina Z [ORNL; Walker, Lakeisha MH [ORNL; Voisin, Sophie [ORNL; Hussey, Dan [NIST Center for Neutron Research (NCRN), Gaithersburg, MD

2013-01-01T23:59:59.000Z

403

Diabatic Heating in the UCLA General Circulation Model  

Science Conference Proceedings (OSTI)

Diabatic heating rates calculated in the UCLA general circulation model are analyzed. The heating rates are for the December–January–February season for the mean of four climatological runs and the mean of four runs with observed 1982/83 sea ...

Bryan C. Weare

1988-07-01T23:59:59.000Z

404

Approximating the traffic grooming problem in tree and star networks  

Science Conference Proceedings (OSTI)

We consider the problem of grooming paths in all-optical networks with tree topology so as to minimize the switching cost, measured by the total number of used ADMs. We first present efficient approximation algorithms with approximation factor of 2 ln ... Keywords: add-drop multiplexer (ADM), optical networks, traffic grooming, tree networks, wavelength division multiplexing (WDM)

Michele Flammini; Gianpiero Monaco; Luca Moscardelli; Mordechai Shalom; Shmuel Zaks

2006-06-01T23:59:59.000Z

405

On the progressive iteration approximation property and alternative iterations  

Science Conference Proceedings (OSTI)

This note revisits the progressive iteration approximation property and some recent modifications from the point of view of iterative methods for solving linear systems. In particular we show the connection with the classical Richardson iteration and ... Keywords: GMRES, Interpolation, Iterative methods, Progressive iteration approximation

J. M. Carnicer; J. Delgado; J. M. Peña

2011-12-01T23:59:59.000Z

406

A constrained binary knapsack approximation for shortest path network interdiction  

Science Conference Proceedings (OSTI)

A modified shortest path network interdiction model is approximated in this work by a constrained binary knapsack which uses aggregated arc maximum flow as the objective function coefficient. In the modified shortest path network interdiction problem, ... Keywords: Approximation techniques, Homeland security, Integer programming, Network interdiction

Justin Yates; Kavitha Lakshmanan

2011-11-01T23:59:59.000Z

407

Error estimates for the numerical approximation of Neumann control problems  

Science Conference Proceedings (OSTI)

We continue the discussion of error estimates for the numerical analysis of Neumann boundary control problems we started in Casas et al. (Comput. Optim. Appl. 31:193-219, 2005). In that paper piecewise constant functions were used to approximate the ... Keywords: boundary control, error estimates, numerical approximation, semilinear elliptic equation

Eduardo Casas; Mariano Mateos

2008-04-01T23:59:59.000Z

408

On-line Approximate String Matching in Natural Language  

Science Conference Proceedings (OSTI)

We consider approximate pattern matching in natural language text. We use the words of the text as the alphabet, instead of the characters as in traditional string matching approaches. Hence our pattern consists of a sequence of words. From the algorithmic ... Keywords: Approximate string matching, filtering, natural language processing, phrase matching, word alphabet

Kimmo Fredriksson

2006-09-01T23:59:59.000Z

409

Quantile approximations in auto-regressive portfolio models  

Science Conference Proceedings (OSTI)

This paper develops an analytical approximation for the distribution function of a terminal value of a periodic series of buy-and-hold investments placed over a fixed time horizon for the case when log-returns of assets follow a p-th order vector auto-regressive ... Keywords: Multi-period portfolio return, Taylor conditioned approximation, Vector auto-regressive returns

Aleš Ah?an; Igor Masten; Sašo Polanec; Mihael Perman

2011-02-01T23:59:59.000Z

410

Thermodynamic Consistency of the Anelastic Approximation for a Moist Atmosphere  

Science Conference Proceedings (OSTI)

The primary goal of this paper is to validate the use of the anelastic approximation for fluids with a complex equation of state such as moist air or seawater. The anelastic approximation is based on a leading-order expansion of the equations of ...

Olivier Pauluis

2008-08-01T23:59:59.000Z

411

Reasoning with rough description logics: An approximate concepts approach  

Science Conference Proceedings (OSTI)

The current research progress and the existing problems of uncertain or imprecise knowledge representation and reasoning in description logics are analyzed in this paper. Approximate concepts are introduced to description logics based on rough set theory, ... Keywords: Approximate concepts, Concepts, Description logics, Rough description logics, Rough set theory

Yuncheng Jiang; Ju Wang; Suqin Tang; Bao Xiao

2009-02-01T23:59:59.000Z

412

Neural Acceleration for General-Purpose Approximate Programs  

Science Conference Proceedings (OSTI)

This paper describes a learning-based approach to the acceleration of approximate programs. We describe the \\emph{Parrot transformation}, a program transformation that selects and trains a neural network to mimic a region of imperative code. After the ... Keywords: Approximate Computing, Neural Networks, Accelerator, Neural Processing Unit, NPU

Hadi Esmaeilzadeh; Adrian Sampson; Luis Ceze; Doug Burger

2012-12-01T23:59:59.000Z

413

Approximating Selective Sweeps by Richard Durrett and Jason Schweinsberg  

E-Print Network (OSTI)

Approximating Selective Sweeps by Richard Durrett and Jason Schweinsberg Dept. of Math, Cornell U of selective sweeps on genealogies. However, most subsequent work has simplified their approach by assuming that the impact of a selective sweep can be accurately approximated by a random partition created by a stick

Durrett, Richard

414

An approximation algorithm for convex multi-objective programming problems  

Science Conference Proceedings (OSTI)

In multi-objective convex optimization it is necessary to compute an infinite set of nondominated points. We propose a method for approximating the nondominated set of a multi-objective nonlinear programming problem, where the objective functions and ... Keywords: ?-nondominated point, Approximation algorithm, Convex optimization, Multi-objective optimization

Matthias Ehrgott; Lizhen Shao; Anita Schöbel

2011-07-01T23:59:59.000Z

415

Energy Basics: Absorption Heat Pumps  

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

but by a heat source such as natural gas, propane, solar-heated water, or geothermal-heated water. Because natural gas is the most common heat source for absorption heat...

416

PSNC Energy (Gas) - Green Building Rate Discount | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

PSNC Energy (Gas) - Green Building Rate Discount PSNC Energy (Gas) - Green Building Rate Discount PSNC Energy (Gas) - Green Building Rate Discount < Back Eligibility Commercial Residential Savings Category Heating & Cooling Home Weatherization Construction Commercial Weatherization Commercial Heating & Cooling Design & Remodeling Solar Lighting Windows, Doors, & Skylights Heating Buying & Making Electricity Water Heating Wind Program Info State North Carolina Program Type Utility Rate Discount Rebate Amount $0.05 discount/therm Provider PSNC Energy This discounted rate is available to commercial customers whose building meets the U.S. Green Building Council's Leadership in Energy and Environmental Design (LEED) certification or equivalent. To qualify, the customer must be on the Rate 125. Qualifying customers pay $.05 per therm

417

Expert Meeting Report: Exploring the Disconnect Between Rated and Field  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exploring the Disconnect Between Rated and Exploring the Disconnect Between Rated and Field Performance of Water Heating Systems Expert Meeting Report: Exploring the Disconnect Between Rated and Field Performance of Water Heating Systems Water heating represents a major residential energy end use, especially in highly efficient homes where space conditioning loads and energy use has been significantly reduced. Future efforts to reduce water heating energy use requires the development of an improved understanding of equipment performance, as well as recognizing system interactions related to the distribution system and the fixture use characteristics. By bringing together a group of water heating experts, we hope to advance the shared knowledge on key water heating performance issues and identify additional

418

Application of district heating system to U. S. urban areas  

DOE Green Energy (OSTI)

In the last few decades district-heating systems have been widely used in a number of European countries using waste heat from electric generation or refuse incineration, as well as energy from primary sources such as geothermal wells or fossil-fired boilers. The current world status of district-heat utilization is summarized. Cost and implementation projections for district-heating systems in the U. S. are discussed in comparison with existing modes of space conditioning and domestic water heating. A substantial fraction, i.e., up to approximately one-half of the U.S. population could employ district-heating systems using waste heat, with present population-distribution patterns. U.S. energy usage would be reduced by an equivalent of approximately 30 percent of current oil imports. Detailed analyses of a number of urban areas are used to formulate conceptual district energy-supply systems, potential implementation levels, and projected energy costs. Important national ancillary economic and social benefits are described, and potential difficulties relating to the implementation of district-heating systems in the U.S. are discussed. District-heating systems appear very attractive for meeting future U.S. energy needs. The technology is well established. The cost/benefit yield is favorable, and the conservation potential is significant. District heating can be applied in urban and densely populated suburban areas. The remaining demand, in rural and low-population-density communities, appears to be better suited to other forms of system substitution.

Karkheck, J.; Powell, J.

1978-01-01T23:59:59.000Z

419

Cylindrical model of transient heat conduction in automotive fuse using conservative averaging method  

Science Conference Proceedings (OSTI)

Cylindrical mathematical model of automotive fuse is considered in this paper. Initially, partial differential equations of the transient heat conduction are given to describe heat-up process in the fuse. Conservative averaging method is used to obtain ... Keywords: analytical approximation, automotive fuse, conservative averaging, heat transfer, quasi-linear, transient process

Raimonds Vilums; Hans-Dieter Liess; Andris Buikis; Andis Rudevics

2008-12-01T23:59:59.000Z

420

Energy Basics: Air-Source Heat Pumps  

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

Systems Air-Source Heat Pumps Ductless Mini-Split Heat Pumps Absorption Heat Pumps Geothermal Heat Pumps Supporting Equipment for Heating & Cooling Systems Water Heating...

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Latent heat accumulating greenhouse  

Science Conference Proceedings (OSTI)

This invention relates to a latent heat accumulating greenhouse utilizing solar heat. The object of the invention is to provide a greenhouse which is simple in construction, of high efficiency for heat absorbing and capable of much absorbing and accumulating of heat. A heat accumulating chamber partitioned by transparent sheets is provided between the attic and a floor surface facing north in the greenhouse. A blower fan is disposed to confront an opening provided at the lower portion in said heat accumulating chamber. Also, in the heat accumulating chamber, a heat accumulating unit having a large number of light transmitting windows and enclosing a phase transformation heat accumulating material such as CaC1/sub 2/.6H/sub 2/O, Na/sub 2/SO/sub 4/.10H/sub 2/O therein is detachably suspended in a position close to windowpanes at the north side.

Yano, N.; Ito, H.; Makido, I.

1985-04-16T23:59:59.000Z

422

Numerical analysis of vapor flow in a micro heat pipe  

E-Print Network (OSTI)

The vapor flow in a flat plate micro heat pipe with both uniform and linear heat flux boundary conditions has been numerically analyzed. For both types of boundary conditions, the Navier-Stokes equations with steady incompressible two-dimensional flow were solved using the SIMPLE method. The results indicate that the pressure, shear stress, and friction factor under linear heat flux boundary conditions are considerably smoother, and hence, more closely approximate the real situation. As the heat flux increases, the pressure drop increases, but the friction factor demonstrates only a slight change for different heat flux conditions. The size and shape of the micro heat pipe vapor space was shown to have a significant influence on the vapor flow behavior for micro heat pipes. When the vapor space area decreases, the pressure drop, shear stress, and friction factor all significantly increase.

Liu, Xiaoqin

1996-01-01T23:59:59.000Z

423

Heat transfer characteristics of a three-phase volume boiling direct contact heat exchanger  

DOE Green Energy (OSTI)

The advantages of direct contact heat transfer over heat transfer utilizing conventional metallic heat exchangers are listed. The performance characteristics of a three-phase direct contact heat exchanger in near counterflow operation were evaluated using water as the continuous phase fluid and refrigerant 113 as the dispersed phase fluid. Conclusions are drawn from the results having to do with refrigerant injection technique, vessel operating height, mass flow rate of refrigerant, water inlet temperature, operation at pinch point temperature differences below 13 to 20/sup 0/C, and operation with a dispersed phase fluid less dense than water. (MHR)

Blair, C.K.; Boehm, R.F.; Jacobs, H.R.

1976-03-01T23:59:59.000Z

424

Heat transfer system  

DOE Patents (OSTI)

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

Not Available

1980-03-07T23:59:59.000Z

425

Heat transfer system  

DOE Patents (OSTI)

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

McGuire, Joseph C. (Richland, WA)

1982-01-01T23:59:59.000Z

426

Laundry heat recovery system  

SciTech Connect

A laundry heat recovery system includes a heat exchanger associated with each dryer in the system, the heat exchanger being positioned within the exhaust system of the dryer. A controller responsive to the water temperature of the heat exchangers and the water storage for the washer selectively circulates the water through a closed loop system whereby the water within the exchangers is preheated by the associated dryers. By venting the exhaust air through the heat exchanger, the air is dehumidified to permit recirculation of the heated air into the dryer.

Alio, P.

1985-04-09T23:59:59.000Z

427

Wound tube heat exchanger  

DOE Patents (OSTI)

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

Ecker, Amir L. (Duncanville, TX)

1983-01-01T23:59:59.000Z

428

Nonequilibrium Electromagnetic Fluctuations: Heat Transfer and Interactions  

Science Conference Proceedings (OSTI)

The Casimir force between arbitrary objects in equilibrium is related to scattering from individual bodies. We extend this approach to heat transfer and Casimir forces in nonequilibrium cases where each body, and the environment, is at a different temperature. The formalism tracks the radiation from each body and its scatterings by the other objects. We discuss the radiation from a cylinder, emphasizing its polarized nature, and obtain the heat transfer between a sphere and a plate, demonstrating the validity of proximity transfer approximation at close separations and arbitrary temperatures.

Krueger, Matthias; Kardar, Mehran [Massachusetts Institute of Technology, Department of Physics, Cambridge, Massachusetts 02139 (United States); Emig, Thorsten [Laboratoire de Physique Theorique et Modeles Statistiques, CNRS UMR 8626, Ba circumflex timent 100, Universite Paris-Sud, 91405 Orsay cedex (France)

2011-05-27T23:59:59.000Z

429

Heat Exchangers for Solar Water Heating Systems | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Heat Exchangers for Solar Water Heating Systems Heat Exchangers for Solar Water Heating Systems Heat Exchangers for Solar Water Heating Systems May 30, 2012 - 3:40pm Addthis Image of a heat exchanger. | Photo from iStockphoto.com Image of a heat exchanger. | Photo from iStockphoto.com Solar water heating systems use heat exchangers to transfer solar energy absorbed in solar collectors to the liquid or air used to heat water or a space. Heat exchangers can be made of steel, copper, bronze, stainless steel, aluminum, or cast iron. Solar heating systems usually use copper, because it is a good thermal conductor and has greater resistance to corrosion. Types of Heat Exchangers Solar water heating systems use three types of heat exchangers: Liquid-to-liquid A liquid-to-liquid heat exchanger uses a heat-transfer fluid that

430

Approximate Coulomb distortion effects in (e,e'p) reactions  

E-Print Network (OSTI)

In this paper we apply a well-tested approximation of electron Coulomb distortion effects to the exclusive reaction (e,e'p) in the quasielastic region. We compare the approximate treatment of Coulomb distortion effects to the exact distorted wave Born approximation evaluated by means of partial wave analysis to gauge the quality of our approximate treatment. We show that the approximate M\\"oller potential has a plane-wave-like structure and hence permits the separation of the cross section into five terms which depend on bilinear products of transforms of the transition four current elements. These transforms reduce to Fourier transforms when Coulomb distortion is not present, but become modified with the inclusion of Coulomb distortion. We investigate the application of the approximate formalism to a model of 208Pb(e,e'p) using Dirac-Hartree single particle wave functions for the ground state and relativistic optical model wave functions for the continuum proton. We show that it is still possible to extract, albeit with some approximation, the various structure functions from the experimentally measured data even for heavy nuclei.

K. S. Kim; L. E. Wright

2005-03-30T23:59:59.000Z

431

System Modeling of Gas Engine Driven Heat Pump  

SciTech Connect

To improve the system performance of the GHP, modeling and experimental study has been made by using desiccant system in cooling operation (particularly in high humidity operations) and suction line waste heat recovery to augment heating capacity and efficiency. The performance of overall GHP system has been simulated by using ORNL Modulating Heat Pump Design Software, which is used to predict steady-state heating and cooling performance of variable-speed vapor compression air-to-air heat pumps for a wide range of operational variables. The modeling includes: (1) GHP cycle without any performance improvements (suction liquid heat exchange and heat recovery) as a baseline (both in cooling and heating mode), (2) the GHP cycle in cooling mode with desiccant system regenerated by waste heat from engine incorporated, (3) GHP cycle in heating mode with heat recovery (recovered heat from engine). According to the system modeling results, by using desiccant system regenerated by waste heat from engine, the SHR can be lowered to 40%. The waste heat of the gas engine can boost the space heating efficiency by 25% in rated operating conditions.

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

2012-01-01T23:59:59.000Z

432

Heat pipe effect in porous medium  

SciTech Connect

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

Joseph, M.

1992-12-01T23:59:59.000Z

433

Dynamics of heat transfer between nano systems  

E-Print Network (OSTI)

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.

Svend-Age Biehs; Girish S. Agarwal

2012-10-18T23:59:59.000Z

434

Utility Rate Discounts | Open Energy Information  

Open Energy Info (EERE)

Discounts Discounts Jump to: navigation, search A few electric utilities offer rate discounts to encourage residential energy efficiency. For homes that meet certain energy efficiency criteria, such as those established by the federal Energy Star program, the owner or tenant is awarded a percentage discount on each monthÂ’s electric bill. [1] Contents 1 Utility Rate Discount Incentives 2 References Utility Rate Discount Incentives CSV (rows 1 - 14) Incentive Incentive Type Place Applicable Sector Eligible Technologies Active Cleco Power - Power Miser New Home Program (Louisiana) Utility Rate Discount Louisiana Residential Building Insulation Central Air conditioners Clothes Washers Comprehensive Measures/Whole Building Doors Duct/Air sealing Furnaces Heat pumps

435

Control system for fluid heated steam generator  

DOE Patents (OSTI)

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.

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

1985-01-01T23:59:59.000Z

436

Control system for fluid heated steam generator  

DOE Patents (OSTI)

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.

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

1984-05-29T23:59:59.000Z

437

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

DOE Patents (OSTI)

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

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

2006-05-16T23:59:59.000Z

438

Section D: SPACE HEATING  

U.S. Energy Information Administration (EIA)

Central warm-air furnace with ducts to individual rooms other than a heat pump ..... 03 Steam/Hot water ... REVERSE Heat pump ... Don't have a separate water heater ...

439

Heat pipe fabrication  

SciTech Connect

A heat pipe is disclosed which is fabricated with an artery arranged so that the warp and weave of the wire mesh are at about a 45/sup 0/ angle with respect to the axis of the heat pipe.

Leinoff, S.; Edelstein, F.; Combs, W.

1977-01-18T23:59:59.000Z

440

Electric Resistance Heating  

Energy.gov (U.S. Department of Energy (DOE))

Electric resistance heat can be supplied by centralized forced-air electric furnaces or by heaters in each room. Electric resistance heating converts nearly all of the energy in the electricity to...

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Space Heating and Cooling  

Energy.gov (U.S. Department of Energy (DOE))

A wide variety of technologies are available for heating and cooling homes and other buildings. In addition, many heating and cooling systems have certain supporting equipment in common, such as...

442

Total Space Heat-  

Gasoline and Diesel Fuel Update (EIA)

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

443

HEAT TRANSFER IN UNDERGROUND HEATING EXPERIMENTS IN GRANITE, STRIPA, SWEDEN  

E-Print Network (OSTI)

CLOSED-FORM INTEGRAL SOLUTIONS FOR LINEAR HEAT CONDUCTION.For linear heat conduction in a homogeneous, isotropiclaw of similitude for linear heat conduction was utilized to

Chan, T.

2010-01-01T23:59:59.000Z

444

HEAT TRANSFER IN UNDERGROUND HEATING EXPERIMENTS IN GRANITE, STRIPA, SWEDEN  

E-Print Network (OSTI)

Analysis of. Nonlinear Heat Transfer Problems." Report no.Berkeley, Ca. , APPENDIX A. HEAT TRANSFER BY CONDUCTION ANDMeeting, Technical Session on Heat Transfer in Nuclear Waste

Chan, T.

2010-01-01T23:59:59.000Z

445

Consolidated Electric Cooperative- Heat Pump and Water Heating Rebates  

Energy.gov (U.S. Department of Energy (DOE))

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

446

Application Study of a Single House Horizontal Heating System  

E-Print Network (OSTI)

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 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 intermedium of horizontal heating system. To simplify the workload of engineering process and make the design more accurate, a new method for calculating the average temperature of the intermedium and the heat flow rate of this heating system is put forward. Comparison is also made between the system in question and the heating system in series. A few important questions are raised and discussed, such as the computation of combining different forms of radiators, the verification of the pipe radiation, the end of the radiator without spanning pipe, and the selection of the pipe diameter. At the same time, we study the influence of the horizontal heating system on the whole heating network, describe the characteristics of a single household horizontal heating system and the importance of its hydraulic computation, and analyze the influence of the gravitational head to this heating system. We also study the hydraulic condition of the single house horizontal system and the relationship of each party under the adjustment. In addition, the operation of single household horizontal heating system is verified in a real project, and its reliability is testified. This paper provides a method for further research on related issues of a single household metering heating system and is valuable for design, operation and management.

Hang, Y.; Ying, D.

2006-01-01T23:59:59.000Z

447

Abrasion resistant heat pipe  

DOE Patents (OSTI)

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

Ernst, D.M.

1984-10-23T23:59:59.000Z

448

Flue heat reclaimer  

Science Conference Proceedings (OSTI)

A flue heat reclaimer is constructed to be mounted on the exterior of a flue duct of a heater and provide a spiral-shaped heat transfer passage extending around the flue duct. A fan causes air to flow through the heat transfer passage so that the temperature of this air is elevated by reason at its extended heat transfer relationship with the flue duct.

Paolino, R.J.

1983-05-03T23:59:59.000Z

449

Solar heat receiver  

DOE Patents (OSTI)

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.

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

1985-01-01T23:59:59.000Z

450

Solar heat receiver  

DOE Patents (OSTI)

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.

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

1982-09-29T23:59:59.000Z

451

Abrasion resistant heat pipe  

DOE Patents (OSTI)

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

Ernst, Donald M. (Leola, PA)

1984-10-23T23:59:59.000Z

452

Heat generation in natural gas adsorption systems  

SciTech Connect

Experiments were conducted using a high-surface-area carbon as an adsorbent for methane to determine the impact of the heat of adsorption upon the storage capacity. The rapid filling of an adsorption storage system under conditions in which the heat of adsorption is not dissipated results in only about 75% of the methane being stored at 3.44 MPa (500 psia) as can be stored by a slow fill rate with heat dissipation. These results depend upon the initial temperature of the absorbent bed and upon the characteristics of the substrate itself. 4 refs., 5 figs.

Remick, R.J.; Tiller, A.J.

1986-01-01T23:59:59.000Z

453

Heat deliverability of homogeneous geothermal reservoirs  

DOE Green Energy (OSTI)

For the last two decades, the petroleum industry has been successfully using simple inflow performance relationships (IPR's) to predict oil deliverability. In contrast, the geothermal industry lacked a simple and reliable method to estimate geothermal wells' heat deliverability. To address this gap in the standard geothermal-reservoir-assessment arsenal, we developed generalized dimensionless geothermal inflow performance relationships (GIPR's). These ''reference curves'' may be regarded as an approximate general solution of the equations describing the practically important case of radial 2-phase inflow. Based on this approximate solution, we outline a straightforward approach to estimate the reservoir contribution to geothermal wells heat and mass deliverability for 2-phase reservoirs. This approach is far less costly and in most cases as reliable as numerically modeling the reservoir, which is the alternative for 2-phase inflow.

Iglesias, Eduardo R.; Moya, Sara L.

1991-01-01T23:59:59.000Z

454

Heat deliverability of homogeneous geothermal reservoirs  

SciTech Connect

For the last two decades, the petroleum industry has been successfully using simple inflow performance relationships (IPR's) to predict oil deliverability. In contrast, the geothermal industry lacked a simple and reliable method to estimate geothermal wells' heat deliverability. To address this gap in the standard geothermal-reservoir-assessment arsenal, we developed generalized dimensionless geothermal inflow performance relationships (GIPR's). These ''reference curves'' may be regarded as an approximate general solution of the equations describing the practically important case of radial 2-phase inflow. Based on this approximate solution, we outline a straightforward approach to estimate the reservoir contribution to geothermal wells heat and mass deliverability for 2-phase reservoirs. This approach is far less costly and in most cases as reliable as numerically modeling the reservoir, which is the alternative for 2-phase inflow.

Iglesias, Eduardo R.; Moya, Sara L.

1991-01-01T23:59:59.000Z

455

Waste Heat Recovery – Submerged Arc Furnaces (SAF)  

E-Print Network (OSTI)

Submerged Arc Furnaces are used to produce high temperature alloys. These furnaces typically run at 3000°F using high voltage electricity along with metallurgical carbon to reduce metal oxides to pure elemental form. The process as currently designed consumes power and fuel that yields an energy efficiency of approximately 40% (Total Btu’s required to reduce to elemental form/ Btu Input). The vast majority of heat is lost to the atmosphere or cooling water system. The furnaces can be modified to recover this heat and convert it to power. The system will then reduce the amount of purchased power by approximately 25% without any additional use of fuel. The cost of this power is virtually unchanged over the life of the project because of the use of capital to displace fuel consumed from the purchased power source.

O'Brien, T.

2008-01-01T23:59:59.000Z

456

WKBJ Approximation of the Stability of a Frontal Mean State  

Science Conference Proceedings (OSTI)

The baroclinic instability of a frontal mean state is investigated using the WKBJ approximation. The results are compared with numerical calculations performed on the same mean state. Excellent agreement (within 5%) is found for jets whose half-...

Petros Ioannou; Richard S. Lindzen

1990-12-01T23:59:59.000Z

457

An empirical comparison of some approximate methods for graph coloring  

Science Conference Proceedings (OSTI)

The Graph Coloring Problem (GCP) is a classical NP-complete problem for which several approximate solution algorithms have been proposed: Brelaz algorithm, simulated annealing (SA), ant colony optimization (ACO). This paper reports empirical results ... Keywords: graph coloring, gravitational swarm

Israel Rebollo-Ruiz; Manuel Graña

2012-03-01T23:59:59.000Z

458

The Approximating Hamiltonian Method for the Imperfect Boson Gas  

E-Print Network (OSTI)

The pressure for the Imperfect (Mean Field) Boson gas can be derived in several ways. The aim of the present note is to provide a new method based on the Approximating Hamiltonian argument which is extremely simple and very general.

Joseph V. Pule; Valentin A. Zagrebnov

2004-05-14T23:59:59.000Z

459

Approximate expressions for polar gap electric field of pulsars  

E-Print Network (OSTI)

We derive easy-to-handle approximations for the polar gap electric field due to inertial frame dragging as derived by Harding & Muslimov 1998. A simple formula valid for polar gap height comparable to the polar cap radius is presented.

J. Dyks; B. Rudak

2000-06-19T23:59:59.000Z

460

Testing and Comparing the Modified Anomalous Diffraction Approximation  

Science Conference Proceedings (OSTI)

The modified anomalous diffraction approximation (MADA) is used to predict absorption and extinction in water and ice clouds, but it does not predict the scattering phase function or asymmetry parameter g. In conjunction with g parameterizations, ...

David L. Mitchell; Anthony J. Baran; W. P. Arnott; C. Schmitt

2006-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Numerical Tests of the Weak Pressure Gradient Approximation  

Science Conference Proceedings (OSTI)

Cloud-resolving simulations of convection over a surface temperature hot spot are used to evaluate the weak pressure gradient (WPG) and weak temperature gradient (WTG) approximations. The premise of the relaxed form of WTG—that vertical velocity ...

David M. Romps

2012-09-01T23:59:59.000Z

462

Approximate translation : media, narrative, and experience in urban design  

E-Print Network (OSTI)

Approximate translation is developed as a design process through which the place-embedded history of an urban environment can be understood, allowing for better design and intervention in that urban environment. Generally, ...

Crisman, Jonathan

2013-01-01T23:59:59.000Z

463

Relativistic plasma dispersion functions: Series, integrals, and approximations  

SciTech Connect

A number of results are presented involving the plasma dispersion functions appropriate to waves in weakly relativistic, magnetized, thermal plasmas. These results include generating functions, series, integral forms and interrelations, and several useful approximations.

Robinson, P.A.

1987-05-01T23:59:59.000Z

464

Statistical theory of Langmuir turbulence. [Direct interaction approximation  

SciTech Connect

A statistical theory of Langmuir turbulence is developed by applying a generalization of the direction interaction approximation (DIA) of Kraichnan to the Zakharov equations describing Langmuir turbulence. 7 references.

DuBois, D.F.; Rose, H.A.; Goldman, M.V.

1979-01-01T23:59:59.000Z

465

A Practical Approximation to Optimal Four-Dimensional Objective Analysis  

Science Conference Proceedings (OSTI)

An iterative four-dimensional objective analysis scheme is described. The method is derived by approximating a variational algorithm which should give an optimal four-dimensional analysis The complete set of operationally available observations, ...

Andrew C. Lorenc

1988-03-01T23:59:59.000Z

466

A discrete BGK approximation for strongly degenerate parabolic problems  

E-Print Network (OSTI)

A discrete BGK approximation for strongly degenerate parabolic problems with boundary conditions F strongly degenerate hyperbolic--parabolic equations with initial boundary condition. We prove a priori -- strongly degenerate parabolic equations -- singular perturbation problems -- BGK models 1 Introduction

467

Approximate query answering in unstructured peer-to-peer databases.  

E-Print Network (OSTI)

??Peer-to-peer networks are considered the new generation of distributed databases, termed peer-to-peer databases. With very large size, open architecture, and extreme dynamism and autonomy, approximate… (more)

Banaei-Kashani, Farnoush

2007-01-01T23:59:59.000Z

468

On the Median Volume Diameter Approximation for Droplet Collision Efficiency  

Science Conference Proceedings (OSTI)

In this note, we examine a shortcut for calculating the overall collision efficiency of a droplet spectrum, known as the “median volume diameter” (mvd) approximation. By calculating the overall collision efficiency of a circular cylinder for a ...

Karen J. Finstad; Edward P. Lozowski; Lasse Makkonen

1988-12-01T23:59:59.000Z

469

A Free-Algebraic Solution for the Planar Approximation  

E-Print Network (OSTI)

An explicit solution for the generating functional of n-point functions in the planar approximation is given in terms of two sets of free-algebraic annihilation and creation operators.

O. Haan

2004-08-11T23:59:59.000Z

470

On Safe Tractable Approximations of Chance Constrained Linear ...  

E-Print Network (OSTI)

†Faculty of Industrial Engineering and Management, Technion – Israel Institute of Technology, ... its scenario approximation is the random optimization program min x. { f0(x) : fi(x ..... We generate a training sample of N independent realizations.

471

Approximation algorithms for stochastic scheduling on unrelated machines  

E-Print Network (OSTI)

Motivated by problems in distributed computing, this thesis presents the first nontrivial polynomial time approximation algorithms for an important class of machine scheduling problems. We study the family of preemptive ...

Scott, Jacob (Jacob Healy)

2008-01-01T23:59:59.000Z

472

Potential Vorticity Conservation, Hydrostatic Adjustment, and the Anelastic Approximation  

Science Conference Proceedings (OSTI)

An examination of the anelastic equations of Lipps and Hemler shows that the approximation requires the temperature and potential temperature scale heights of the base state are large compared to the pressure and density scale heights. As a ...

Peter R. Bannon

1995-06-01T23:59:59.000Z

473

Approximate dynamic programming with applications in multi-agent systems  

E-Print Network (OSTI)

This thesis presents the development and implementation of approximate dynamic programming methods used to manage multi-agent systems. The purpose of this thesis is to develop an architectural framework and theoretical ...

Valenti, Mario J. (Mario James), 1976-

2007-01-01T23:59:59.000Z

474

HEAT TRANSFER MEANS  

DOE Patents (OSTI)

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

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

1961-07-11T23:59:59.000Z

475

Liquid heat capacity lasers  

DOE Patents (OSTI)

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

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

2007-05-01T23:59:59.000Z

476

Approximating the traffic grooming problem in tree and star networks  

Science Conference Proceedings (OSTI)

We consider the problem of grooming paths in all-optical networks with tree topology so as to minimize the switching cost, measured by the total number of used ADMs. We first present efficient approximation algorithms with approximation factor of 2ln(@d@?g)+o(ln(@d@?g)) ... Keywords: Add-drop multiplexer (ADM), Optical networks, Traffic grooming, Tree networks, Wavelength division multiplexing (WDM)

Michele Flammini; Gianpiero Monaco; Luca Moscardelli; Mordechai Shalom; Shmuel Zaks

2008-07-01T23:59:59.000Z

477

Indexing methods for approximate dictionary searching: Comparative analysis  

Science Conference Proceedings (OSTI)

The primary goal of this article is to survey state-of-the-art indexing methods for approximate dictionary searching. To improve understanding of the field, we introduce a taxonomy that classifies all methods into direct methods and sequence-based filtering ... Keywords: k-errata tree, q-gram, q-sample, Damerau-Levenshtein distance, Levenshtein distance, NR-grep, agrep, approximate searching, frequency distance, frequency vector trie, metric trees, neighborhood generation, trie

Leonid Boytsov

2011-05-01T23:59:59.000Z

478

Heating facilities: Klamath Lutheran Church, Klamath Falls, Oregon  

DOE Green Energy (OSTI)

The Klamath Lutheran Church is a masonry structure with cathedral ceiling containing approximately 5800 sq ft of floor area. This building is currently heated by two duct furnaces and a unit heater all of which are gas fired. An Educational Wing of approximately 6300 sq ft was added in 1958. This building, containing 2 assembly rooms and a number of classrooms is of uninsulated frame construction, with extensive glass area. A gas-fired boiler supplying finned tube radiators currently heats this wing. Four specific options for displacing all or part of the heating duty with geothermal were examined. These options are: case 1 - drilling a production and injection well on the property and using the resultant hot water (180/sup 0/F) to heat the entire facility; case 3 - using effluent from the Klamath Union High School to heat the entire facility; no well drilling required; case 2 - using effluent from the Klamath Union High School to heat only the church building; the present gas boiler would heat the Educational Wing; and case 4 - drilling a production and injection well on the property and using the resulting water (70/sup 0/F) to supply a water-to-water heat pump. Of the four cases examined, case 3 (heating of both the church building and educational wing with effluent from the Klamath Union High School) seems to offer the greatest potential and earliest simple payback period. (MHR)

Not Available

1980-08-01T23:59:59.000Z

479

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

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

DOE Announces Award of a Contract to Repurchase Heating Oil for the DOE Announces Award of a Contract to Repurchase Heating Oil for the Northeast Home Heating Oil Reserve DOE Announces Award of a Contract to Repurchase Heating Oil for the Northeast Home Heating Oil Reserve July 23, 2008 - 2:15pm Addthis WASHINGTON, DC - The U.S. Department of Energy today announced the award of a contract to Hess Corporation for the delivery of approximately 808,625 gallons (approximately 19,250 barrels) of home heating oil for the Northeast Home Heating Oil Reserve (NEHHOR). The purchased oil is expected to be delivered to the Hess First Reserve terminal at Perth Amboy, NJ in New York Harbor later this week. The award resulted from a solicitation issued on June 23, 2008, to repurchase heating oil using $3 million in funds appropriated after the

480

Energy Basics: Geothermal Heat Pumps  

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

EERE: Energy Basics Geothermal Heat Pumps Geothermal heat pumps use the constant temperature of the earth as an exchange medium for heat. Although many parts of the country...

Note: This page contains sample records for the topic "approximate heat rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

A corrosive resistant heat exchanger  

DOE Patents (OSTI)

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.

Richlen, S.L.

1987-08-10T23:59:59.000Z

482

Natural convection heat exchangers for solar water heating systems. Technical progress report, May 15, 1996--July 14, 1996  

DOE Green Energy (OSTI)

This progress report very briefly summarizes study results and includes an experimental plan developed for the fundamental study of heat transfer in thermosyphon side-arm heat exchangers. The study will investigate the influence of the Reynolds and Grashof numbers on the thermosyphon flow side of the heat exchanger, and the influence of the flow rate on the forced flow side of the heat exchanger. Detailed temperature, flow rate, and pressure data will be obtained for four, seven, and nine tube-in-shell heat exchanger designs. Correlations will be developed for the heat transfer and friction coefficients, and a semi-empirical model will be developed to predict the performance of thermosyphon heat exchangers in solar water heaters.

Davidson, J.H.

1998-06-01T23:59:59.000Z

483

Applied heat transfer  

Science Conference Proceedings (OSTI)

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

Ganapathy, V.

1982-01-01T23:59:59.000Z

484

Absorption heat pump system  

DOE Patents (OSTI)

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

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

1984-01-01T23:59:59.000Z

485

Plasma heat pump and heat engine  

Science Conference Proceedings (OSTI)

A model system where cold charged particles are locally confined in a volume V{sub P} within a warm plasma of volume V (V{sub P}kilowatts is possible with the present day technology. Second, we discuss the feasibility of constructing an electrostatic heat engine which converts plasma heat into mechanical work via plasma electric fields. Effects of P{sub E} are shown to be observable in colloidal solutions.

Avinash, K. [Centre for Space Plasma and Aeronomic Research, University of Alabama, Huntsville, Alabama 35899 (United States) and Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India)

2010-08-15T23:59:59.000Z

486

HEAT TRANSFER IN UNDERGROUND HEATING EXPERIMENTS IN GRANITE, STRIPA, SWEDEN  

E-Print Network (OSTI)

law of similitude for linear heat conduction was utilized tothe analogy between heat conduction and fluid flow in por­the effects of heat conduction through the vermiculite heat

Chan, T.

2010-01-01T23:59:59.000Z

487

Heat pump apparatus  

DOE Patents (OSTI)

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

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

1983-01-01T23:59:59.000Z

488

Residential Heating Oil Prices  

Gasoline and Diesel Fuel Update (EIA)

This chart highlights residential heating oil prices for the current and This chart highlights residential heating oil prices for the current and past heating season. As you can see, prices have started the heating season, about 40 to 50 cents per gallon higher than last year at this time. The data presented are from EIA's State Heating Oil and Propane Program. We normally collect and publish this data twice a month, but given the low stocks and high prices, we started tracking the prices weekly. These data will also be used to determine the price trigger mechanism for the Northeast Heating Oil Reserve. The data are published at a State and regional level on our web site. The slide is to give you some perspective of what is happening in these markets, since you probably will get a number of calls from local residents about their heating fuels bills

489

Switchable heat pipe assembly  

SciTech Connect

The heat pipe assembly is formed into an H-shape or a Y-shape. The H-shaped configuration comprises two heat pipes, each having condenser and evaporator sections with wicking therein coupled by a tube with wick at their evaporator sections. The Y-shaped configuration utilizes a common evaporator section in place of the two evaporator sections of the H-shaped configuration. In both configurations, the connection between the vapor spaces of the two heat pipes equalizes vapor pressure within the heat pipes. Although both heat pipes have wicks, they have sufficient fluid only to saturate a single pipe. If heat is applied to the condenser section of one of the pipes, this heat pipe becomes inoperative since all the fluid is transferred to the second pipe which can operate with a lower thermal load.

Sun, T.H.; Basiulis, A.

1977-02-15T23:59:59.000Z

490

Active microchannel heat exchanger  

DOE Patents (OSTI)

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

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

2001-01-01T23:59:59.000Z

491

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

Science Conference Proceedings (OSTI)

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

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

2011-01-01T23:59:59.000Z

492

Data Center Rating Infrastructure Rating Development  

NLE Websites -- All DOE Office Websites (Extended Search)

in Portfolio Manager on June 7, 2010. The questions below are designed to help data center owners and operators better understand the rating and benchmark their buildings in...

493

Numerical Hurricane Prediction Using Assimilation of Remotely-Sensed Rainfall Rates  

Science Conference Proceedings (OSTI)

Rainfall rates determined from airborne radar and infrared satellite images are combined to construct a space- and time-dependent heating function for Hurricane Anita (1977). The heating is assimilated into a three-dimensional primitive equation ...

John Molinari

1982-06-01T23:59:59.000Z

494

Carbon Material Based Heat Exchanger for Waste Heat Recovery ...  

Industrial processing plants Nuclear power Solar power ... Carbon Material Based Heat Exchanger for Waste Heat Recovery from Engine Exhaust Contact:

495

HEAT TRANSFER IN UNDERGROUND HEATING EXPERIMENTS IN GRANITE, STRIPA, SWEDEN  

E-Print Network (OSTI)

standing of the heat transfer processes associated withto investigate the heat transfer and related processes in an

Chan, T.

2010-01-01T23:59:59.000Z

496

A model for improvement of water heating heat exchanger designs for residential heat pump water heaters.  

E-Print Network (OSTI)

??Heat pump water heaters are a promising technology to reduce energy use and greenhouse gas emissions. A key component is the water heating heat exchanger.… (more)

Weerawoot, Arunwattana

2010-01-01T23:59:59.000Z

497

Sand Mountain Electric Cooperative - Residential Heat Pump Loan Program |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Sand Mountain Electric Cooperative - Residential Heat Pump Loan Sand Mountain Electric Cooperative - Residential Heat Pump Loan Program Sand Mountain Electric Cooperative - Residential Heat Pump Loan Program < Back Eligibility Residential Savings Category Heating & Cooling Commercial Heating & Cooling Heat Pumps Program Info State Alabama Program Type Utility Loan Program Rebate Amount 7% interest rate 5 or 10 year pay schedule maximum of $12,000 Provider Sand Mountain Electric Cooperative The Sand Mountain Electric Cooperative offers a heat pump loan program to eligible residential members. To qualify, members must have had power with Sand Mountain Electric Cooperative for at least one year, have the home electric bill and deeds in the same name, and pass a credit check. Heat pumps must be installed by a [http://www.smec.coop/heatpumpcontractors.htm