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1

Benefits of the International Residential Code's Maximum Solar heat Gain Coefficient Requirement for Windows  

E-Print Network [OSTI]

Texas adopted in its residential building energy code a maximum 0.40 solar heat gain coefficient (SHGC) for fenestration (e.g., windows, glazed doors and skylights)-a critical driver of cooling energy use, comfort and peak demand. An analysis...

Stone, G. A.; DeVito, E. M.; Nease, N. H.

2002-01-01T23:59:59.000Z

2

Heat-transfer coefficients in agitated vessels. Latent heat models  

SciTech Connect (OSTI)

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

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

1996-03-01T23:59:59.000Z

3

SOLAR HEAT GAIN THROUGH FENESTRATION SYSTEMS CONTAINING SHADING: PROCEDURES FOR ESTIMATING  

E-Print Network [OSTI]

SOLAR HEAT GAIN THROUGH FENESTRATION SYSTEMS CONTAINING SHADING: PROCEDURES FOR ESTIMATING that with a drastic simplifying assumption these methods can be used to calculate system solar-optical properties and solar heat gain coefficients for arbitrary glazing systems, while requiring limited data about

4

SOLAR HEAT GAIN THROUGH FENESTRATION SYSTEMS CONTAINING SHADING: SUMMARY OF PROCEDURES FOR  

E-Print Network [OSTI]

SOLAR HEAT GAIN THROUGH FENESTRATION SYSTEMS CONTAINING SHADING: SUMMARY OF PROCEDURES that with a drastic simplifying assumption these methods can be used to calculate system solar-optical properties and solar heat gain coefficients for arbitrary glazing systems, while requiring limited data about

5

Heat-transfer coefficients in agitated vessels. Sensible heat models  

SciTech Connect (OSTI)

Transient models for sensible heat were developed to assess the thermal performance of agitated vessels with coils and jackets. Performance is quantified with the computation of heat-transfer coefficients by introducing vessel heating and cooling data into model equations. Of the two model categories studied, differential and macroscopic, the latter is preferred due to mathematical simplicity and lower sensitivity to experimental data variability.

Kumpinsky, E. [Ashland Chemical Co., Columbus, OH (United States). Research and Development Dept.

1995-12-01T23:59:59.000Z

6

Outside heat transfer coefficients for atmospheric coolers  

E-Print Network [OSTI]

for the same conditions of operation is given by Robinson ()i. 9). TABLE I Comparison of various authors' values of outside heat transfer coefficients Btugour x square foot x F ~ ) Adams (1 ) 1001 1041 915 74, 6 1021 981 910 Clarke 945 997 841... ozeventing any recycling of the wet air. "M~4~ 1 f jc, : 1 C. X L, w 38 Cooled water fro~ the tower is centrifugally pmnoed through a 2 inch pipe to a rotameter and a I and operated control valve, Figure 8, before entering a 1 1/g inch by 5 foot...

George, David Mark

1950-01-01T23:59:59.000Z

7

CORRELATING EVAPORATION HEAT TRANSFER COEFFICIENT OF REFRIGERANT R-134a IN A PLATE HEAT EXCHANGER  

E-Print Network [OSTI]

1 CORRELATING EVAPORATION HEAT TRANSFER COEFFICIENT OF REFRIGERANT R-134a IN A PLATE HEAT EXCHANGER for evaporation heat transfer coefficient of refrigerant R-134a flowing in a plate heat exchanger. Correlation schemes proposed by Yan and Lin (1999b) for modeling the heat transfer coefficient in both a single- phase

Kandlikar, Satish

8

Work and energy gain of heat-pumped quantized amplifiers  

E-Print Network [OSTI]

We investigate heat-pumped single-mode amplifiers of quantized fields in high-Q cavities based on non-inverted two-level systems. Their power generation is shown to crucially depend on the capacity of the quantum state of the field to accumulate useful work. By contrast, the energy gain of the field is shown to be insensitive to its quantum state. Analogies and differences with masers are explored.

David Gelbwaser-Klimovsky; Robert Alicki; Gershon Kurizki

2013-10-09T23:59:59.000Z

9

Incremental cooling load determination for passive direct gain heating systems  

SciTech Connect (OSTI)

This paper examines the applicability of the National Association of Home Builders (NAHB) full load compressor hour method for predicting the cooling load increase in a residence, attributable to direct gain passive heating systems. The NAHB method predictions are compared with the results of 200 hour-by-hour simulations using BLAST and the two methods show reasonable agreement. The degree of agreement and the limitations of the NAHB method are discussed.

Sullivan, P.W.; Mahone, D.; Fuller, W.; Gruber, J.; Kammerud, R.; Place, W.; Andersson, B.

1981-05-01T23:59:59.000Z

10

Heat transfer coefficients in three phase fluidized beds  

SciTech Connect (OSTI)

In order to obtain a semitheoretical correlation for the heat transfer coefficients in three phase fluidized beds, Deckwer's semitheoretical correlation for the heat transfer coefficients in the bubble column, which was derived from Higbie's surface renewal theory of interphase mass transfer with the concept of isotropic turbulence, has been extended to three phase fluidized beds with the modification of the energy dissipation rate. One of the desirable characteristics of three phase fluidized beds is the uniformity of temperature in the bed. The intense longitudinal and transverse turbulent mixing in a fluidized bed may induce the uniform fields of temperature and solids concentration. For highly exothermic reactions, the uniform temperature in the bed is essential to avoid the local hot spots. In order to control the uniform temperature of three phase fluidized beds, the addition or removal of heat in the bed is required and the information on heat transfer surface and the bed is essential to designing the heat exchanger. Recently, Chiu and Ziegler (1983) determined wall-to-bed heat transfer coefficients in three phase fluidized bed (5.08 cm ID) of glass beads and cylindrical gamma alumina particles which were fluidized by cocurrent flow of air and water. Their data were correlated in terms of the modified Colburn j factor. Kato et al. (1981) measured wall-to-bed heat transfer coefficients in three phase fluidized beds of 5.2 and 12.0 cm internal diameter. Four different sizes of glass beads (0.42-2.2 mm) were fluidized by air and aqueous carboxymethyl cellulose solutions. The coefficients increased with decrease in liquid viscosity and with increase in gas and liquid velocity.

Suh, I.S.; Jin, G.T.; Kim, S.D.

1985-03-01T23:59:59.000Z

11

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

E-Print Network [OSTI]

the Hydraulic Drag and Heat Transfer Coefficients in PorousT. E. W. , 1929, “Heat Transfer: A Liquid Flowing Through a5] Locke, G. L. , 1950, “Heat Transfer and Flow Friction

Geb, David; Zhou, Feng; Catton, Ivan

2012-01-01T23:59:59.000Z

12

Effect of Mixed Working Fluid Composition on Binary Cycle Condenser Heat Transfer Coefficients  

SciTech Connect (OSTI)

Effect of Mixed Working Fluid Composition on Binary Cycle Condenser Heat Transfer Coefficients Dan Wendt, Greg Mines Idaho National Laboratory The use of mixed working fluids in binary power plants can provide significant increases in plant performance, provided the heat exchangers are designed to take advantage of these fluids non-isothermal phase changes. In the 1980's testing was conducted at DOE's Heat Cycle Research Facility (HCRF) where mixtures of different compositions were vaporized at supercritical pressures and then condensed. This testing had focused on using the data collected to verify that Heat Transfer Research Incorporated (HTRI) codes were suitable for the design of heat exchangers that could be used with mixtures. The HCRF data includes mixture compositions varying from 0% to 40% isopentane and condenser tube orientations of 15{sup o}, 60{sup o}, and 90{sup o} from horizontal. Testing was performed over a range of working fluid and cooling fluid conditions. Though the condenser used in this testing was water cooled, the working fluid condensation occurred on the tube-side of the heat exchanger. This tube-side condensation is analogous to that in an air-cooled condenser. Tube-side condensing heat transfer coefficient information gleaned from the HCRF testing is used in this study to assess the suitability of air-cooled condenser designs for use with mixtures. Results of an air-cooled binary plant process model performed with Aspen Plus indicate that that the optimal mixture composition (producing the maximum net power for the scenario considered) is within the range of compositions for which data exist. The HCRF data is used to assess the impact of composition, tube orientation, and process parameters on the condensing heat transfer coefficients. The sensitivity of the condensing coefficients to these factors is evaluated and the suitability of air-cooled condenser designs with mixtures is assessed. This paper summarizes the evaluation of the HCRF data and discusses the next steps in the project evaluation of air-cooled condenser designs that can take advantage of the performance gains possible with these fluids.

Dan Wendt; Greg Mines

2011-10-01T23:59:59.000Z

13

Coat Color and Solar Heat Gain in Animals Author(s): Glenn E. Walsberg  

E-Print Network [OSTI]

when exposed to solar radiation than do light surfaces. For ani- mals such as birds or mammalsCoat Color and Solar Heat Gain in Animals Author(s): Glenn E. Walsberg Source: BioScience, Vol. 33://www.jstor.org #12;Coat Color and Solar Heat Gain in Animals Glenn E. Walsberg The relationbetween coat color

Cavitt, John F.

14

Scaling of Heat Transfer Coefficients Along Louvered Fins A. C. Lyman1  

E-Print Network [OSTI]

1 Scaling of Heat Transfer Coefficients Along Louvered Fins A. C. Lyman1 , R. A. Stephan2 , and K 23681-2199 #12;2 Abstract Louvered fins provide a method for improving the heat transfer performance for evaluating the spatially-resolved louver heat transfer coefficients using various reference temperatures

Thole, Karen A.

15

Flow Boiling Heat Transfer Coefficient In Minichannels Correlation and Trends Satish G. Kandlikar  

E-Print Network [OSTI]

Flow Boiling Heat Transfer Coefficient In Minichannels ­ Correlation and Trends Satish G. Kandlikar York 14623, USA The flow boiling heat transfer in small diameter passages is being applied in many boiling heat transfer coefficient with the correlations developed for conventional channels. It is found

Kandlikar, Satish

16

PTG exam 9 April 2014 short answers 123. Heat given off = surface * heat transfer coefficient * temperature = A * h * T  

E-Print Network [OSTI]

= Q34 = h4 ­ h3 = 2173,3 kJ/kg d. Heat input = Q15 = h1 ­ h5 = h1 ­ h4 + 4 (pump power) = 2831,0 kPTG exam 9 April 2014 short answers 123. Heat given off = surface * heat transfer coefficient * temperature = A * h * T Heat transfer coefficient from Nunumber, which for natural convection

Zevenhoven, Ron

17

Analysis of Proper Depth for Gaining Seawater Heat  

E-Print Network [OSTI]

and seawater temperatures near the city. · It is impossible to get deep sea water for Busan area, since Kim (Dongeui University) · Ki-Chang Chang (Korea Institute of Energy Research) #12;1. Introduction · Use of heat from seawater could be different from the weather conditions of a coastal city

18

Room location (design) in accordance with the sol-air temperature and solar heat gain  

E-Print Network [OSTI]

ROOM LOCATION (DESIGN) IN ACCORDANCE WITH THE SOL-AIR TEMPERATURE AND SOLAR HEAT GAIN A Thesis GARY LYNN PORTER Submitted to the Graduate College of Texas ASM University in parital fulfillment of the requirement for the degree of MASTER... OF SCIENCE May 1977 Major Subject: Meteorology ROOM LOCATION (DESIGN) IN ACCORDANCE WITH THE SOL-AIR TEMPERATURE AND SOLAR HEAT GAIN A Thesis by GARY LYNN PORTER Approved as to style and content by: hairman of Committee) (Head of Department) ( (Q...

Porter, Gary Lynn

1977-01-01T23:59:59.000Z

19

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

E-Print Network [OSTI]

)" #12;1. Introduction Brazed aluminium heat exchangers are composed of flat tubes on the refrigerant exchangers with round tube, such as charge reduction and higher heat transfer coefficient. But, according are thus not suitable to small-channel heat exchangers. As a consequence, the refrigerant distribution

Boyer, Edmond

20

Dynamic measurement of heat loss coefficients through Trombe wall glazing systems  

SciTech Connect (OSTI)

A Trombe wall presents a unique opportunity to measure the heat-loss coefficient through the glazing system because the wall itself can be used as a heat meter. Since the instantaneous heat flux through the outer wall surface can be determined, the heat loss coefficient at night can be calculated by dividing by the wall surface-to-ambient temperature difference. This technique has been used to determine heat-loss coefficients for Los Alamos test rooms during the winter of 1980-1981. Glazing systems studied include single and double glazing both with and without night insulation used in conjunction with a flat black paint, and both single and double glazing used in conjunction with a selective surface.

Balcomb, J.D.

1981-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heat gain coefficient" 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

Solar Heat Gain through a Skylight in a Light Well J. H. Klems  

E-Print Network [OSTI]

Solar Heat Gain through a Skylight in a Light Well J. H. Klems Building Technologies Department on a skylight mounted on a light well of significant depth are presented. It is shown that during the day much of the solar energy that strikes the walls of the well does not reach the space below. Instead, this energy

22

Measuring solar reflectance Part I: Defining a metric that accurately predicts solar heat gain  

SciTech Connect (OSTI)

Solar reflectance can vary with the spectral and angular distributions of incident sunlight, which in turn depend on surface orientation, solar position and atmospheric conditions. A widely used solar reflectance metric based on the ASTM Standard E891 beam-normal solar spectral irradiance underestimates the solar heat gain of a spectrally selective 'cool colored' surface because this irradiance contains a greater fraction of near-infrared light than typically found in ordinary (unconcentrated) global sunlight. At mainland U.S. latitudes, this metric RE891BN can underestimate the annual peak solar heat gain of a typical roof or pavement (slope {le} 5:12 [23{sup o}]) by as much as 89 W m{sup -2}, and underestimate its peak surface temperature by up to 5 K. Using R{sub E891BN} to characterize roofs in a building energy simulation can exaggerate the economic value N of annual cool-roof net energy savings by as much as 23%. We define clear-sky air mass one global horizontal ('AM1GH') solar reflectance R{sub g,0}, a simple and easily measured property that more accurately predicts solar heat gain. R{sub g,0} predicts the annual peak solar heat gain of a roof or pavement to within 2 W m{sup -2}, and overestimates N by no more than 3%. R{sub g,0} is well suited to rating the solar reflectances of roofs, pavements and walls. We show in Part II that R{sub g,0} can be easily and accurately measured with a pyranometer, a solar spectrophotometer or version 6 of the Solar Spectrum Reflectometer.

Levinson, Ronnen; Akbari, Hashem; Berdahl, Paul

2010-05-14T23:59:59.000Z

23

Abstract. Tailored porous media is a proposed method of achieving higher heat transfer coefficients while seeking to  

E-Print Network [OSTI]

Abstract. Tailored porous media is a proposed method of achieving higher heat transfer coefficients general porous flow model (MERLOT [1]). The Model of Energy- transfer Rate for fLow in Open transfer performance. The low heat capacities and low heat transfer coefficients, h, of gas coolants

Raffray, A. René

24

ASHRAE Transactions 103(1) (1997). Solar Heat Gain Coefficient of Complex Fenestrations  

E-Print Network [OSTI]

Technologies Program Energy and Environment Division Ernest Orlando Lawrence Berkeley National Laboratory Division Ernest Orlando Lawrence Berkeley National Laboratory Berkeley, CA 94792 ABSTRACT Measured account of * Present address: Energy Analysis Program, Ernest Orlando Lawrence Berkeley National

25

Diurnal heat storage in direct-gain passive-solar buildings  

SciTech Connect (OSTI)

This paper presents a simplified method for predicting temperature swings in direct-gain buildings. It is called the DHC method due to the use of a diurnal heat capacity (DHC). Diurnal heat capacity is a measure of the effective amount of heat stored during a sunny day and then released at night - the typical 24-hour diurnal cycle. This enables prediction of the maximum temperature swings experienced in the building and can be calculated using a single 24-hour harmonic. The advantage is that closed-form analytic solutions can be obtained for a variety of simple and layered-wall configurations. Higher harmonic components are accounted for by a correction factor. The method is suitable for us by hand or on a programmable calculator.

Balcomb, J.D.; Neeper, D.A.

1983-01-01T23:59:59.000Z

26

Heat transfer coefficients in two-dimensional Yukawa systems (numerical simulations)  

SciTech Connect (OSTI)

New data on heat transfer in two-dimensional Yukawa systems have been obtained. The results of a numerical study of the thermal conductivity for equilibrium systems with parameters close to the conditions of laboratory experiments in dusty plasma are presented. The Green-Kubo relations are used to calculate the heat transfer coefficients. The influence of dissipation (internal friction) on the heat transfer processes in nonideal systems is studied. New approximations are proposed for the thermal conductivity and diffusivity for nonideal dissipative systems. The results obtained are compared with the existing experimental and numerical data.

Khrustalyov, Yu. V., E-mail: yuri.khrustalyov@gmail.com; Vaulina, O. S. [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation)

2013-05-15T23:59:59.000Z

27

Heat kernel Coefficients and Divergencies of the Casimir Energy for the Dispersive Sphere  

E-Print Network [OSTI]

The first heat kernel coefficients are calculated for a dispersive ball whose permittivity at high frequency differs from unity by inverse powers of the frequency. The corresponding divergent part of the vacuum energy of the electromagnetic field is given and ultraviolet divergencies are seen to be present. Also in a model where the number of atoms is fixed the pressure exhibits infinities. As a consequence, the ground-state energy for a dispersive dielectric ball cannot be interpreted easily.

M. Bordag; K. Kirsten

2001-10-24T23:59:59.000Z

28

The contact heat conductance at diamond-OFHC copper interface with GaIn eutectic as a heat transfer medium  

SciTech Connect (OSTI)

Results of an experimental study of the contact heat conductance across a single diamond crystal interface with OFHC copper (Cu) are reported. Gallium-indium (GaIn) eutectic was used as an interstitial material. Contact conductance data are important in the design and the prediction of the performance of x-ray diamond monochromators under high-heat-load conditions. Two sets of experiments were carried out. In one, the copper surface in contact with diamond was polished and then electroless plated with 1 {mu}m of nickel, while in the other, the copper contact surface was left as machined. Measured average interface heat conductances are 44.7 {plus_minus}8 W/cm{sup 2}{minus}K for nonplated copper and 23.0 {plus_minus}3 W/cm{sup 2}{minus}K for nickel-plated copper. For reference, the thermal contact conductances at a copper-copper interface (without diamond) were also measured, and the results are reported. A typical diamond monochromator, 0.2 mm thick, will absorb about 44 W under a standard undulator beam at the Advanced Photon Source. The measured conductance for nickel-plated copper suggests that the temperature drop across the interface of diamond and nickel-plated copper, with a 20 mm{sup 2} contact area, will be about 10{degree}C. Therefore temperature rises are rather modest, and the accuracy of the measured contact conductances presented here are sufficient for design purposes.

Assoufid, L.; Khounsary, A.M.

1996-01-01T23:59:59.000Z

29

Contact heat conductance at a diamond-OFHC copper interface with GaIn eutectic as a heat transfer medium  

SciTech Connect (OSTI)

The results of an experimental study of the contact heat conductance across a single diamond crystal interface with OFHC copper (Cu) are reported. Gallium-indium (GaIn) eutectic was used as an interstitial material. Contact conductance data are important in the design and the prediction of the performance of x-ray optics under high-heat-load conditions. Two sets of experiments were carried out. In one, the copper surface in contact with diamond was polished and then electroless plated with 1 {mu}m of nickel, while in the other, the copper contact surface was left as machined. The measured average interface heat conductances are 44.7{plus_minus}8 W/cm{sup 2}-K for nonplated copper and 23.0{plus_minus}8 W/cm{sup 2}-K for nickel-plated copper. For reference, the thermal contact conductances at a copper-copper interface (without diamond) were also measured, and the results are reported. A typical diamond monochromator, 0.2 mm thick, will absorb about 44 W under a standard undulator beam at the Advanced Photon Source. The measured conductance for nickel-plated copper suggests that the temperature drop across the interface of diamond and nickel-plated copper, with a 20 mm {sup 2}contact area, will be about 10{degree}C. Therefore temperature rises are rather modest, and the accuracy of the measured contact conductances presented here are sufficient for design purposes. {copyright} {ital 1996 American Institute of Physics.}

Assoufid, L.; Khounsary, A. [Experimental Facilities Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)] [Experimental Facilities Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

1996-09-01T23:59:59.000Z

30

Systematics of the Relationship between Vacuum Energy Calculations and Heat Kernel Coefficients  

E-Print Network [OSTI]

Casimir energy is a nonlocal effect; its magnitude cannot be deduced from heat kernel expansions, even those including the integrated boundary terms. On the other hand, it is known that the divergent terms in the regularized (but not yet renormalized) total vacuum energy are associated with the heat kernel coefficients. Here a recent study of the relations among the eigenvalue density, the heat kernel, and the integral kernel of the operator $e^{-t\\sqrt{H}}$ is exploited to characterize this association completely. Various previously isolated observations about the structure of the regularized energy emerge naturally. For over 20 years controversies have persisted stemming from the fact that certain (presumably physically meaningful) terms in the renormalized vacuum energy density in the interior of a cavity become singular at the boundary and correlate to certain divergent terms in the regularized total energy. The point of view of the present paper promises to help resolve these issues.

S. A. Fulling

2003-04-03T23:59:59.000Z

31

Determination of thermal accommodation coefficients from heat transfer measurements between parallel plates.  

SciTech Connect (OSTI)

Thermal accommodation coefficients have been derived for a variety of gas-surface combinations using an experimental apparatus developed to measure the pressure dependence of the conductive heat flux between parallel plates at unequal temperature separated by a gas-filled gap. The heat flux is inferred from temperature-difference measurements across the plates in a configuration where the plate temperatures are set with two carefully controlled thermal baths. Temperature-controlled shrouds provide for environmental isolation of the opposing test plates. Since the measured temperature differences in these experiments are very small (typically 0.3 C or less over the entire pressure range), high-precision thermistors are used to acquire the requisite temperature data. High-precision components have also been utilized on the other control and measurement subsystems in this apparatus, including system pressure, gas flow rate, plate alignment, and plate positions. The apparatus also includes the capability for in situ plasma cleaning of the installed test plates. Measured heat-flux results are used in a formula based on Direct Simulation Monte Carlo (DSMC) code calculations to determine the thermal accommodation coefficients. Thermal accommodation coefficients have been determined for three different gases (argon, nitrogen, helium) in contact with various surfaces. Materials include metals and alloys such as aluminum, gold, platinum, and 304 stainless steel. A number of materials important to fabrication of Micro Electro Mechanical Systems (MEMS) devices have also been examined. For most surfaces, coefficient values are near 0.95, 0.85, and 0.45 for argon, nitrogen, and helium, respectively. Only slight differences in accommodation as a function of surface roughness have been seen. Surface contamination appears to have a more significant effect: argon plasma treatment has been observed to reduce thermal accommodation by as much as 0.10 for helium. Mixtures of argon and helium have also been examined, and the results have been compared to DSMC simulations incorporating thermal-accommodation values from single-species experiments.

Gallis, Michail A.; Castaneda, Jaime N.; Rader, Daniel John; Torczynski, John Robert; Trott, Wayne Merle

2010-10-01T23:59:59.000Z

32

Abstract--The use of structured porous media is a proposed technique to achieve higher heat transfer coefficients by  

E-Print Network [OSTI]

transfer coefficients by increasing the specific surface area for heat transfer while aiming to maintain pressure drop for a given heat transfer performance. A comprehensive thermo-fluid model called MERLOT [1] was used to assess the use of porous heat transfer media for fusion plasma facing component applications

Pulsifer, John

33

NUMERICAL DETERMINATION AND TREATMENT OF CONVECTIVE HEAT TRANSFER COEFFICIENT IN THE COUPLED BUILDING ENERGY AND CFD SIMULATION  

E-Print Network [OSTI]

for the correct prediction of the convective heat. A finer grid resolution in CFD does not always lead to a more conservation equations of flow on these grid cells. As shown in Figure 1(a), CFD calculates convective heat1 NUMERICAL DETERMINATION AND TREATMENT OF CONVECTIVE HEAT TRANSFER COEFFICIENT IN THE COUPLED

Chen, Qingyan "Yan"

34

Device and method for measuring the coefficient of performance of a heat pump  

DOE Patents [OSTI]

A method and instrument is provided which allows quick and accurate measurement of the coefficient of performance of an installed electrically powered heat pump including auxiliary resistane heaters. Temperature-sensitive resistors are placed in the return and supply air ducts to measure the temperature increase of the air across the refrigerant and resistive-heating elements of the system. The voltages across the resistors which are directly proportional to the respective duct tempertures are applied to the inputs of a differential amplifier so that its output voltage is proportional to the temperature difference across the unit. A voltage-to-frequency converter connected to the output of the differential amplifier converts the voltage signal to a proportional-frequency signal. A digital watt meter is used to measure the power to the unit and produces a signal having a frequency proportional to the input power. A digital logic circuit ratios the temperature difference signal and the electric power input signal in a unique manner to produce a single number which is the coefficient of performance of the unit over the test interval. The digital logic and an in-situ calibration procedure enables the instrument to make these measurements in such a way that the ratio of heat flow/power input is obtained without computations. No specialized knowledge of thermodynamics or electrons is required to operate the instrument.

Brantley, V.R.; Miller, D.R.

1982-05-18T23:59:59.000Z

35

Device and method for measuring the coefficient of performance of a heat pump  

DOE Patents [OSTI]

A method and instrument is provided which allows quick and accurate measurement of the coefficient of performance of an installed electrically powered heat pump including auxiliary resistance heaters. Temperature sensitive resistors are placed in the return and supply air ducts to measure the temperature increase of the air across the refrigerant and resistive heating elements of the system. The voltages across the resistors which are directly proportional to the respective duct temperatures are applied to the inputs of a differential amplifier so that its output voltage is proportional to the temperature difference across the unit. A voltage-to-frequency converter connected to the output of the differential amplifier converts the voltage signal to a proportional frequency signal. A digital watt meter is used to measure the power to the unit and produces a signal having a frequency proportional to the input power. A digital logic circuit ratios the temperature difference signal and the electric power input signal in a unique manner to produce a single number which is the coefficient of performance of the unit over the test interval. The digital logic and an in-situ calibration procedure enables the instrument to make these measurements in such a way that the ratio of heat flow/power input is obtained without computations. No specialized knowledge of thermodynamics or electronics is required to operate the instrument.

Brantley, Vanston R. (Knoxville, TN); Miller, Donald R. (Kingston, TN)

1984-01-01T23:59:59.000Z

36

Effect of combined nanoparticle and polymeric dispersions on critical heat flux, nucleate boiling heat transfer coefficient, and coating adhesion  

E-Print Network [OSTI]

An experimental study was performed to determine thermal performance and adhesion effects of a combined nanoparticle and polymeric dispersion coating. The critical heat flux (CHF) values and nucleate boiling heat transfer ...

Edwards, Bronwyn K

2009-01-01T23:59:59.000Z

37

Effect of surfactant on evaporative heat transfer coefficients in vertical film forced convection  

E-Print Network [OSTI]

for different concentrations of surfactant (log-log scale) (Boiling liquid flow rate of 1. 025 gpm) Evaporative coefficient as function of tempera- ture drop over the liquid film for different concentrations of surfactant (log-log scale) (Boiling liquid... flow rate of 1. 275 gpm) Evaporative coefficient as function of tempera- ture drop over the liquid film for different concentrations of surfactant (log-log scale) (Boiling liquid flow rate of 1. 55 gpm) 47 84 85 86 87 10 Evaporative...

Shah, Basit Husain

1972-01-01T23:59:59.000Z

38

The determination of the natural convection heat transfer coefficients for a heated cylinder in air at sub-atmospheric pressures  

E-Print Network [OSTI]

wire. Electrical power leads were attached to all of the heaters and were led through the interior of the entire assembly. Thermal insulation of the heated portion of the test assembly from the support was provided by using a 1-in. long Micarta tube... VI Presentation of Data 37 References 41 LIST OF FIGURES Figure Page Schematic Diagram of the Test Facility The Test Facility The Natural Convection Vacuum Chamber The Test Cylinder Assembly and the Air Temperature Measuring Probe Schematic...

Sullivan, Lawrence Brozak

2012-06-07T23:59:59.000Z

39

Field dependences of magnetization and specific-heat coefficient in a nearly magnetic system: Liquid /sup 3/He and strong Pauli paramagnets  

SciTech Connect (OSTI)

We analytically derive the first-order magnetic-field dependences of the magnetization M and of the coefficient ..gamma.. of the specific heat, in a nearly magnetic paramagnet, at low temperature.

Beal-Monod, M.T.; Daniel, E.

1983-04-01T23:59:59.000Z

40

Measurements of heat and mass transfer coefficients during absorption of water vapor by lithium bromide and (Li,K,Na)NO sub 3 mixtures  

SciTech Connect (OSTI)

A knowledge of heat and mass transfer coefficients in heat pump fluids, plays an important role in the design of absorption machines. Heat and mass transfer coefficients as well as subcooling are measured for absorption of water vapor in (Li, K, Na)No{sub 3} and Lithium Bromide (LiBr) mixtures.The rate of absorption of water vapor is obtained from the difference in concentration of mixtures between inlet and outlet streams across the absorber. In situ concentrations of aqueous salt mixtures over temperature ranges between 80 to 135 {degrees}C were calculated from density measurements. This technique of measurement is a reliable and convenient but not a very accurate ({plus minus}0.8 wt% salt) method of measuring the in situ salt concentration. Results show that the subcooling at the absorber exit is not only a property of the fluid, but depends strongly on the process conditions. The subcooling in LiBr mixtures without additive is shown to vary between 2.2 and 24.3 {degrees}C and the film heat transfer coefficient between 1365.2 and 801.1 W/m{sup 2}.K respectively, depending upon process conditions. These empirical results will prove to be of value to heat pump manufacturers because they have a strong bearing on costs and performance. Heat and mass transfer coefficients in aqueous salt solutions ate presented as a function of dimensionless numbers. 12 refs., 3 figs., 4 tabs.

Zaltash, A.; Ally, M.R.; Linkous, R.L.; Klatt, L.N.

1991-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heat gain coefficient" 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

Economic Analysis and Optimization of Exterior Insulation Requirements for Ventilated Buildings at Power Generation Facilities with High Internal Heat Gain  

E-Print Network [OSTI]

Industrial buildings require a large amount of heating and ventilation equipment to maintain the indoor environment within acceptable levels for personnel protection and equipment protection. The required heating and ventilation equipment...

Hughes, Douglas E.

2010-12-17T23:59:59.000Z

42

A correlation for local coefficients of heat transfer in boiling of R12 and R22 refrigerants on multirow bundles of smooth tubes  

SciTech Connect (OSTI)

Experimental results on the boiling of R12 and R22 on bundles of 30 to 50 vertically stacked rows of smooth tubes are presented and correlated. Engineering equations for determining the coefficients of heat transfer in the pool boiling of freons on such multirow bundles are derived.

Rebrov, P.N.; Bukin, V.G.; Danilova, G.N.

1989-07-01T23:59:59.000Z

43

A Cartesian grid embedded boundary method for solving the Poisson and heat equations with discontinuous coefficients in three dimensions  

E-Print Network [OSTI]

A composite grid solver for conjugate heat transfer in ?uid-A Cartesian grid embedded boundary method for the heatA cartesian grid embedded boundary method for the heat

Crockett, Robert

2010-01-01T23:59:59.000Z

44

Modified heat transfer coefficient in the presence of noncondensible gas for RELAP5/MOD2 computer code  

E-Print Network [OSTI]

. volume flow area of 0. 3491 ft2. A heat source was modelled as being attached to the right surface of the pressurizer. The heat source was also divided into ten sections of equal length. The right surface of the heat slab was considered to have a heat...

Grant, Sharon Elizabeth

1990-01-01T23:59:59.000Z

45

An investigation of the vertical and temporal distributions of the eddy heat-diffusion coefficient near the earth's surface under fair-weather conditions  

E-Print Network [OSTI]

facilities avail- able at the Data Processing Center (DPC), Texas A&M Univer- sity, this investigation would not have been temporally possible. Deep appreciation goes to all DPC personnel for their tireless assistance. Thanks must go to Mr. Lundin, my...-Weather Conditions (January 1965) Eugene Y J, Wong, B. S, , Texas A&M University Directed by: Dr. Kenneth C. Brundidge A numerical scheme was devised to solve the Tavlor heat-diffusion equation for values of the eddy heat- diffusion coefficient, K, using a...

Wong, Eugene You June

1965-01-01T23:59:59.000Z

46

About homotopy perturbation method for solving heat-like and wave-like equations with variable coefficients  

E-Print Network [OSTI]

We analyze a recent application of homotopy perturbation method to some heat-like and wave-like models and show that its main results are merely the Taylor expansions of exponential and hyperbolic functions. Besides, the authors require more boundary conditions than those already necessary for the solution of the problem by means of power series.

Francisco M. Fernandez

2008-11-17T23:59:59.000Z

47

Energy Gaining Windows for Residential Buildings Jesper Kragh, Assistant Professor,  

E-Print Network [OSTI]

season. It is assumed that in northern cold climates all of the solar gain during the heating season can profiles, solar gain, net energy gain, low energy houses SUMMARY: This paper presents some of the research buildings. The net energy gain of windows is the solar gain minus the heat loss integrated over the heating

48

Experimental development of the predictive relations for the eddy exchange coefficients for momentum and heat in the atmospheric boundary layer  

E-Print Network [OSTI]

, increase in w by removing the dummy -1 bases was 4. 2 cm/sec , and u for these runs was 330 cm/sec -I ?? Using sin [w/u] as a measure of the tilt of the wind field gave an inclination of . 72', in fair agreement with KAIMAL's relation. Therefore.... '?'illlam H. Clayton Direct measurements of the eddy fluxes of mo. . . entum and heat were. made in the atmospheric boundary layer simultaneously with measurements of the profiles of average wind velocity and tempera- ture to evaluate the capability...

Jensen, Paul Alfred

2012-06-07T23:59:59.000Z

49

Heat transfer coefficient saturation in superconducting Nb tunnel junctions contacted to a NbTiN circuit and an Au energy relaxation layer  

E-Print Network [OSTI]

In this paper we present the experimental realization of a Nb tunnel junction connected to a high-gap superconducting NbTiN embedding circuit. We investigate relaxation of nonequilibrium quasiparticles in a small volume Au layer between the Nb tunnel junction and the NbTiN circuit. We find a saturation in the effective heat-transfer coefficient consistent with a simple theoretical model. This saturation is determined by the thickness of the Au layer. Our findings are important for the design of the ideal Au energy relaxation layer for practical SIS heterodyne mixers and we suggest two geometries, one, using a circular Au layer and, two, using a half-circular Au layer. Our work is concluded with an outlook of our future experiments.

Selig, Stefan; Jacobs, Karl; Schultz, Michael; Honingh, Netty

2014-01-01T23:59:59.000Z

50

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

51

Effects of internal gain assumptions in building energy calculations  

SciTech Connect (OSTI)

The utilization of direct solar gains in buildings can be affected by operating profiles, such as schedules for internal gains, thermostat controls, and ventilation rates. Building energy analysis methods use various assumptions about these profiles. The effects of typical internal gain assumptions in energy calculations are described. Heating and cooling loads from simulations using the DOE 2.1 computer code are compared for various internal-gain inputs: typical hourly profiles, constant average profiles, and zero gain profiles. Prototype single-family-detached and multi-family-attached residential units are studied with various levels of insulation and infiltration. Small detached commercial buildings and attached zones in large commercial buildings are studied with various levels of internal gains. The results of this study indicate that calculations of annual heating and cooling loads are sensitive to internal gains, but in most cases are relatively insensitive to hourly variations in internal gains.

Christensen, C.; Perkins, R.

1981-01-01T23:59:59.000Z

52

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...

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

2006-01-01T23:59:59.000Z

53

Gaining a World View  

E-Print Network [OSTI]

tx H 2 O | pg. 26 --------------------------------------------- ???????????????????????? W hen Brandon Hartley traveled to Belgium last summer, he gained a first-hand appreciation for international soil and water issues. Hartley, a Texas A...

Wythe, Kathy

2007-01-01T23:59:59.000Z

54

Measurements of thermal accommodation coefficients.  

SciTech Connect (OSTI)

A previously-developed experimental facility has been used to determine gas-surface thermal accommodation coefficients from the pressure dependence of the heat flux between parallel plates of similar material but different surface finish. Heat flux between the plates is inferred from measurements of temperature drop between the plate surface and an adjacent temperature-controlled water bath. Thermal accommodation measurements were determined from the pressure dependence of the heat flux for a fixed plate separation. Measurements of argon and nitrogen in contact with standard machined (lathed) or polished 304 stainless steel plates are indistinguishable within experimental uncertainty. Thus, the accommodation coefficient of 304 stainless steel with nitrogen and argon is estimated to be 0.80 {+-} 0.02 and 0.87 {+-} 0.02, respectively, independent of the surface roughness within the range likely to be encountered in engineering practice. Measurements of the accommodation of helium showed a slight variation with 304 stainless steel surface roughness: 0.36 {+-} 0.02 for a standard machine finish and 0.40 {+-} 0.02 for a polished finish. Planned tests with carbon-nanotube-coated plates will be performed when 304 stainless-steel blanks have been successfully coated.

Rader, Daniel John; Castaneda, Jaime N.; Torczynski, John Robert; Grasser, Thomas W.; Trott, Wayne Merle

2005-10-01T23:59:59.000Z

55

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

56

Gain Sharing.PDF  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeatMulti-Dimensional Subject: Guidance for natural gas asWindEECBGSE DOE/IG-480 I N S

57

Boiling heat transfer in a hydrofoil-based micro pin fin heat sink  

E-Print Network [OSTI]

Boiling heat transfer in a hydrofoil-based micro pin fin heat sink Ali KosÃ?ar, Yoav Peles-based micro pin fin heat sink was investigated. Average two-phase heat transfer coefficients were obtained intermittent and spray-annular flows. Heat transfer coefficient trends and flow morphologies were used to infer

Peles, Yoav

58

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...

Chen, Y.; Zhao, J.

2006-01-01T23:59:59.000Z

59

E-Print Network 3.0 - avalanche gain feasibility Sample Search...  

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

employed. 3.2.2 Gain of an avalanche photodiode. If we denote the electron ionisation... coefficient by h and the width of the depletion layer by w then the ... Source: University...

60

su(3)k fusion coefficients  

E-Print Network [OSTI]

A closed and explicit formula for all $\\su{(3)}_k$ fusion coefficients is presented which, in the limit $k \\rightarrow \\infty$, turns into a simple and compact expression for the $su(3)$ tensor product coefficients. The derivation is based on a new diagrammatic method which gives directly both tensor product and fusion coefficients.

L. Begin; P. Mathieu; M. A. Walton

1992-06-08T23:59:59.000Z

Note: This page contains sample records for the topic "heat gain coefficient" 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

Generalized solar load ratio correlation for direct gain buildings  

SciTech Connect (OSTI)

A generalized solar load ratio correlation has been developed for direct gain buildings by generating relationships between the correlation parameters and two fundamental design parameters. The first design parameter is the steady state conductance of the solar aperture, U/sub c/. The second is the effective heat capacity of the solar zone, EHC.

Wray, W.O.; Best, E.D.

1986-01-01T23:59:59.000Z

62

Mechanical Compression Heat Pumps  

E-Print Network [OSTI]

MECHANICAL COMPRESSION HEAT PUMPS Thomas-L. Apaloo and K. Kawamura Mycom Corporation, Los Angeles, California J. Matsuda, Mayekawa Mfg. Co., Tokyo, Japan ABSTRACT Mechanical compression heat pumping is not new in industrial applications.... In fact, industry history suggests that the theoretical concept was developed before 1825. Heat pump manufacturers gained the support of consultants and end-users when the energy crisis hit this country in 1973. That interest, today, has been...

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

63

A near infrared organic photodiode with gain at low bias voltage  

SciTech Connect (OSTI)

We demonstrate an organic photodiode with near infrared optical response out to about 1100 run with a gain of {approx}10 at 1000 run under 5V reverse bias. The diodes employ a soluble naphthalocyanine with a peak absorption coefficient of {approx}10{sup 5} cm{sup -1} at 1000 nm. In contrast to most organic photodiodes, no exciton dissociating material is used. At zero bias, the diodes are inefficient with an external quantum efficiency of {approx} 10{sup -2}. In reverse bias, large gain occurs and is linear with bias voltage above 4V. The observed gain is consistent with a photoconductive gain mechanism.

Campbell, Ian H [Los Alamos National Laboratory; Crone, Brian K [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

64

Natural Refrigerant (R-729) Heat Pump  

Energy Savers [EERE]

Manufactured in the U.S. 2 Problem Statement * Current commercial and industrial heat pumps - Poor coefficient of performance (COP) at low temperatures * HFC refrigerant...

65

EXPERIMENTAL INVESTIGATION OF BOILING HEAT CONVECTION IN A FRACTURE  

E-Print Network [OSTI]

EXPERIMENTAL INVESTIGATION OF BOILING HEAT CONVECTION IN A FRACTURE A REPORT SUBMITTED between heat conduction and heat convection with boiling flow in a rock fracture. An experimental coefficient. This coefficient is the proportionality factor between the heat flux to a fracture surface

Stanford University

66

INVESTIGATING THE EFFECT OF HEATING METHOD ON POOL BOILING HEAT TRANSFER  

E-Print Network [OSTI]

INVESTIGATING THE EFFECT OF HEATING METHOD ON POOL BOILING HEAT TRANSFER Satish G. Kandlikar surfaces in laboratories to obtain the heat transfer coefficient data. In many process applications however, a fluid stream is employed as the heating medium. The heat transfer data generated with the electrically

Kandlikar, Satish

67

Influence of Heat Transmission Mode on Heating Rates and on the Selection of Patches for Heating in a Mediterranean Lizard  

E-Print Network [OSTI]

369 Influence of Heat Transmission Mode on Heating Rates and on the Selection of Patches for Heating in a Mediterranean Lizard Josabel Belliure* Luis M. Carrascal Department of Evolutionary Ecology´ Gutie´rrez Abascal 2, 28006 Madrid, Spain Accepted 6/6/02 ABSTRACT Heliothermy (heat gain by radiation

Carrascal, Luis M.

68

IntroductiontoProcessEngineering(PTG) 4. Heat exchangers;  

E-Print Network [OSTI]

ProcessEngineering(PTG) VST rz13 8/72 Heat exchangers: energy balance Picture: SEHB06 Heat exchanger schematic with open/72 Overall heat transfer coefficient · The heat transfer process* may be described by a simple model expression Q = U·A·T for temperature diffence T (°C), heat exchange area A (m2) and overall heat transfer

Zevenhoven, Ron

69

Seebeck coefficient in organic semiconductors  

E-Print Network [OSTI]

Seebeck coefficient in organic semiconductors A dissertation submitted for the degree of Doctor of Philosophy Deepak Venkateshvaran Fitzwilliam College & Optoelectronics Group, Cavendish Laboratory University of Cambridge February 2014 “The end...

Venkateshvaran, Deepak

2014-07-01T23:59:59.000Z

70

The Kauffman Constraint Coefficients Kw  

E-Print Network [OSTI]

The Kauffman Constraint Coefficients Kw and their corresponding Elementals Ew are presented as solutions to the construction of the (beta)-derivative of Kauffman's Theta-function. Additionally, a new recursion relation is provided to construct the (beta)-derivative of Theta that requires only operational substitutions and summations; this algorithmically simplifies Kauffman's original technique. To demonstrate Kw, we generate the 30 Kw Coefficients from the corresponding Elementals Ew for the (9)-derivative of Theta and find that our results are in complete agreement with Kauffman's Mathematica\\texttrademark solutions. We further present a calculation of two coefficients for the (12)-derivative of Theta and invite readers to use Mathematica\\texttrademark or any other means to calculate and verify our results. Finally, we present a challenging calculation for a coefficient of the (40)-derivative of Theta; owing to the vast numbers of permutations involved, a Mathematica\\texttrademark approach may require substantial computer resources to obtain the solution in a reasonable time.

Kenneth A. Griggs

2011-10-27T23:59:59.000Z

71

Fuel Temperature Coefficient of Reactivity  

SciTech Connect (OSTI)

A method for measuring the fuel temperature coefficient of reactivity in a heterogeneous nuclear reactor is presented. The method, which is used during normal operation, requires that calibrated control rods be oscillated in a special way at a high reactor power level. The value of the fuel temperature coefficient of reactivity is found from the measured flux responses to these oscillations. Application of the method in a Savannah River reactor charged with natural uranium is discussed.

Loewe, W.E.

2001-07-31T23:59:59.000Z

72

The Production Coefficients of Feeds  

E-Print Network [OSTI]

TEXAS AGRICULTURAL EXPERIMENT STATION BULLETIN NO. 185 FEBRUARY, 1916 DIVISION OF CHEMISTRY The Production Coefficients of Feeds POSTOFFICE: COLLEGE STATION, BRAZOS COUNTY, TEXAS [Blank Page in Original Bulletin] TEXAS AGRICULTURAL EXPERIMENT... STATION pp - -- - - BULLETIN NO. 185 FEBRUARY, 1916 DIVISION OF CHEMISTRY The Production Coefficients of Feeds G. S. FRAPS, Ph. D. CHEMIST IN CHARGE; STATE CHEMIST POSTOFFICE: COLLEGE STATION, BRAZOS COUNTY, TEXAS AUSTIN, TEXAS VON BOECKMANN...

Fraps, G. S. (George Stronach)

1916-01-01T23:59:59.000Z

73

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

74

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

E-Print Network [OSTI]

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

Phillips, Bren Andrew

2011-01-01T23:59:59.000Z

75

The deterioration in heat transfer to fluids at supercritical pressure and high heat fluxes  

E-Print Network [OSTI]

At slightly supercritical pressure and in the neighborhood of the pseudo-critical temperature (defined as the temperature corresponding to the peak in specific heat at the operating pressure), the heat transfer coefficient ...

Shiralkar, B. S.

1968-01-01T23:59:59.000Z

76

Conclusions Observed enhancement in convection heat transfer coefficient in  

E-Print Network [OSTI]

in de-ionized water Commercial System Heater Insulation Water block · The water block replaces/min) di-water 1% nanofluid 0.5% nanofluid Results: Calculated Thermal Conductivity 0.45 0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0 0.5 1 1.5 2 thermalconductivity(W/mK) volume loading (%) calculated di-water

Walker, D. Greg

77

Determination of optimal gains for constrained controllers  

SciTech Connect (OSTI)

In this report, we consider the determination of optimal gains, with respect to a certain performance index, for state feedback controllers where some elements in the gain matrix are constrained to be zero. Two iterative schemes for systematically finding the constrained gain matrix are presented. An example is included to demonstrate the procedures.

Kwan, C.M.; Mestha, L.K.

1993-08-01T23:59:59.000Z

78

Temperature profile of the infrared image Heat exchange between  

E-Print Network [OSTI]

T Temperature profile of the infrared image Heat exchange between atmosphere and ocean References coefficient of heat in water determine the heat transfer velocity: *t Infrared images of the water surface: a-Karls-Universität Heidelberg www.uni-heidelberg.de Active controlled flux technique (ACFT) Continuous heat flux Periodic heat

Jaehne, Bernd

79

Spring 2014 Heat Transfer -2  

E-Print Network [OSTI]

Spring 2014 Heat Transfer - 2 A thin electronic chip is in the shape of a square wafer, b = 1 cm surface of the chip with a heat transfer coefficient of h = 100 W/m2 -K. Assume the chip has a uniform per side with a mass of m = 0.3 grams and specific heat of C = 103 J/kg-K. The chip is mounted

Virginia Tech

80

Portable vapor diffusion coefficient meter  

DOE Patents [OSTI]

An apparatus for measuring the effective vapor diffusion coefficient of a test vapor diffusing through a sample of porous media contained within a test chamber. A chemical sensor measures the time-varying concentration of vapor that has diffused a known distance through the porous media. A data processor contained within the apparatus compares the measured sensor data with analytical predictions of the response curve based on the transient diffusion equation using Fick's Law, iterating on the choice of an effective vapor diffusion coefficient until the difference between the predicted and measured curves is minimized. Optionally, a purge fluid can forced through the porous media, permitting the apparatus to also measure a gas-phase permeability. The apparatus can be made lightweight, self-powered, and portable for use in the field.

Ho, Clifford K. (Albuquerque, NM)

2007-06-12T23:59:59.000Z

Note: This page contains sample records for the topic "heat gain coefficient" 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

High temperature Seebeck coefficient metrology  

SciTech Connect (OSTI)

We present an overview of the challenges and practices of thermoelectric metrology on bulk materials at high temperature (300 to 1300 K). The Seebeck coefficient, when combined with thermal and electrical conductivity, is an essential property measurement for evaluating the potential performance of novel thermoelectric materials. However, there is some question as to which measurement technique(s) provides the most accurate determination of the Seebeck coefficient at high temperature. This has led to the implementation of nonideal practices that have further complicated the confirmation of reported high ZT materials. To ensure meaningful interlaboratory comparison of data, thermoelectric measurements must be reliable, accurate, and consistent. This article will summarize and compare the relevant measurement techniques and apparatus designs required to effectively manage uncertainty, while also providing a reference resource of previous advances in high temperature thermoelectric metrology.

Martin, J. [Materials Science and Engineering Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Tritt, T. [Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634 (United States); Uher, C. [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2010-12-15T23:59:59.000Z

82

High temperature Seebeck coefficient metrology  

SciTech Connect (OSTI)

We present an overview of the challenges and practices of thermoelectric metrology on bulk materials at high temperature (300 to 1300 K). The Seebeck coefficient, when combined with thermal and electrical conductivity, is an essential propertymeasurement for evaluating the potential performance of novel thermoelectricmaterials. However, there is some question as to which measurement technique(s) provides the most accurate determination of the Seebeck coefficient at high temperature. This has led to the implementation of nonideal practices that have further complicated the confirmation of reported high ZT materials. To ensure meaningful interlaboratory comparison of data, thermoelectricmeasurements must be reliable, accurate, and consistent. This article will summarize and compare the relevant measurement techniques and apparatus designs required to effectively manage uncertainty, while also providing a reference resource of previous advances in high temperature thermoelectric metrology.

Martin, J.; Tritt, T.; Uher, Ctirad

2010-01-01T23:59:59.000Z

83

Calculate thermal-expansion coefficients  

SciTech Connect (OSTI)

To properly design and use process equipment, an engineer needs a sound knowledge of physical and thermodynamic property data. A lack of such knowledge can lead to design or operating mistakes that can be dangerous, costly or even fatal. One useful type of property data is the thermal-expansion coefficient. This article presents equations and tables to find the thermal-expansion coefficients of many liquids that contain carbon. These data are useful in process-engineering applications, including the design of relief systems which are crucial to safeguarding process equipment. Data are provided for approximately 350 compounds. A computer software program, which contains the thermophysical property data for all of the compounds discussed in this article, is available for $43 prepaid from the author (Carl L. Yaws, Box 10053, Lamar University, beaumont, TX 77710; Tel. 409-880-8787; fax 409-880-8404). The program is in ASCII format, which can be accessed by most other types of computer software.

Yaws, C.L. [Lamar Univ., Beaumont, TX (United States)

1995-08-01T23:59:59.000Z

84

Optimization Online - Lot sizing with inventory gains  

E-Print Network [OSTI]

Apr 27, 2006 ... Abstract: This paper introduces the single item lot sizing problem with inventory gains. This problem is a generalization of the classical single ...

Hamish Waterer

2006-04-27T23:59:59.000Z

85

Inelastic neutron and low-frequency Raman scattering in a niobium-phosphate glass for Raman gain applications  

E-Print Network [OSTI]

Inelastic neutron and low-frequency Raman scattering in a niobium-phosphate glass for Raman gain: Raman scattering; Neutron scattering; Raman gain; Boson peak We present measurements of the vibrational, extracted from specific-heat or neutron scattering measurements [7,8]. Only very recently two of the present

Schirmacher, Walter

86

TWO WELL STORAGE SYSTEMS FOR COMBINED HEATING AND AIRCONDITIONING BY GROUNDWATER HEATPUMPS IN SHALLOW AQUIFERS  

E-Print Network [OSTI]

In warmer climates air source heat pumps have gained widestadvantages over air source heat pumps. For example, theair conditioning is required, water is pumped from the cold water well to the heat pump.

Pelka, Walter

2010-01-01T23:59:59.000Z

87

TWO WELL STORAGE SYSTEMS FOR COMBINED HEATING AND AIRCONDITIONING BY GROUNDWATER HEATPUMPS IN SHALLOW AQUIFERS  

E-Print Network [OSTI]

In warmer climates air source heat pumps have gained widestadvantages over air source heat pumps. For example, theair source equipment is much less. The source for this kind of heat pump

Pelka, Walter

2010-01-01T23:59:59.000Z

88

Specific-heat discontinuity in impure two-band superconductors  

E-Print Network [OSTI]

The Ginzburg-Landau coefficients and the jump of the specific heat are calculated for a disordered two-band superconductor. We start with the analysis of a more general case with arbitrary anisotropy. While the specific-heat discontinuity...

Mishonov, TM; Penev, ES; Indekeu, JO; Pokrovsky, Valery L.

2003-01-01T23:59:59.000Z

89

Hydrodynamics, heat transfer and flow boiling instabilities in microchannels   

E-Print Network [OSTI]

Boiling in microchannels is a very efficient mode of heat transfer with high heat and mass transfer coefficients achieved. Less pumping power is required for two-phase flows than for single-phase liquid flows to achieve ...

Barber, Jacqueline Claire

2010-01-01T23:59:59.000Z

90

Experimental evaluation of heat transfer characteristics of silica nanofluid  

E-Print Network [OSTI]

The laminar convective heat transfer characteristics were investigated for silica nanofluid. An experimental loop was built to obtain heat transfer coefficients for single-phase nanofluids in a circular conduit in laminar ...

Zhang, Zihao, S.B. Massachusetts Institute of Technology

2010-01-01T23:59:59.000Z

91

DESIGN OF A COMPACT HEAT EXCHANGER FOR HEAT RECUPERATION FROM A HIGH TEMPERATURE ELECTROLYSIS SYSTEM  

SciTech Connect (OSTI)

Design details of a compact heat exchanger and supporting hardware for heat recuperation in a high-temperature electrolysis application are presented. The recuperative heat exchanger uses a vacuum-brazed plate-fin design and operates between 300 and 800°C. It includes corrugated inserts for enhancement of heat transfer coefficients and extended heat transfer surface area. Two recuperative heat exchangers are required per each four-stack electrolysis module. The heat exchangers are mated to a base manifold unit that distributes the inlet and outlet flows to and from the four electrolysis stacks. Results of heat exchanger design calculations and assembly details are also presented.

G. K. Housley; J.E. O'Brien; G.L. Hawkes

2008-11-01T23:59:59.000Z

92

The theoretical ultimate magnetoelectric coefficients of magnetoelectric composites by optimization design  

SciTech Connect (OSTI)

This paper investigates what is the largest magnetoelectric (ME) coefficient of ME composites, and how to realize it. From the standpoint of energy conservation, a theoretical analysis is carried out on an imaginary lever structure consisting of a magnetostrictive phase, a piezoelectric phase, and a rigid lever. This structure is a generalization of various composite layouts for optimization on ME effect. The predicted theoretical ultimate ME coefficient plays a similar role as the efficiency of ideal heat engine in thermodynamics, and is used to evaluate the existing typical ME layouts, such as the parallel sandwiched layout and the serial layout. These two typical layouts exhibit ME coefficient much lower than the theoretical largest values, because in the general analysis the stress amplification ratio and the volume ratio can be optimized independently and freely, but in typical layouts they are dependent or fixed. To overcome this shortcoming and achieve the theoretical largest ME coefficient, a new design is presented. In addition, it is found that the most commonly used electric field ME coefficient can be designed to be infinitely large. We doubt the validity of this coefficient as a reasonable ME effect index and consider three more ME coefficients, namely the electric charge ME coefficient, the voltage ME coefficient, and the static electric energy ME coefficient. We note that the theoretical ultimate value of the static electric energy ME coefficient is finite and might be a more proper measure of ME effect.

Wang, H.-L.; Liu, B., E-mail: liubin@tsinghua.edu.cn [AML, CNMM, Department of Engineering Mechanics, Tsinghua University, Beijing 100084 (China)

2014-03-21T23:59:59.000Z

93

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

E-Print Network [OSTI]

Single-phase convective heat transfer in microchannels: aand Newell, M. E. , 1967. Heat transfer in fully developed3 /s at 130 W. Water CGA Heat Transfer Coefficient, h (W/m 2

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

2006-01-01T23:59:59.000Z

94

Prediction of internal temperature swings in direct-gain passive-solar buildings  

SciTech Connect (OSTI)

The diurnal heat capacity method is presented for estimating inside-temperature swings attributable to direct winter solar gain. The procedures are simplified to be suitable for hand analysis, aided by tables of diurnal heat capacity for various materials. The method has been spot checked against computer simulation and has been used successfully by a group of 20 builders in New Mexico to analyze whether temperature swings would be excessive in their designs.

Balcomb, J.D.

1983-01-01T23:59:59.000Z

95

Experimental Determination of the Gain Distribution of an Avalanche Photodiode at Low Gains  

E-Print Network [OSTI]

A measurement system for determining the gain distributions of avalanche photodiodes (APDs) in a low gain range is presented. The system is based on an ultralow-noise charge--sensitive amplifier and detects the output carriers from an APD. The noise of the charge--sensitive amplifier is as low as 4.2 electrons at a sampling rate of 200 Hz. The gain distribution of a commercial Si APD with low average gains are presented, demonstrating the McIntyre theory in the low gain range.

Kenji Tsujino; Makoto Akiba; Masahide Sasaki

2008-12-04T23:59:59.000Z

96

Heat transfer in the plate heat exchanger of an ammonia-synthesis column  

SciTech Connect (OSTI)

The planning and construction of high-capacity synthetic ammonia plants requires the development and fabrication of unique, high unit-power equipment with high technical and economic characteristics. In foreign and domestic practice, tubular heat exchangers with relatively low heat-transfer coefficients are used. Plate heat exchangers are a promising alternative. They are compact and have a high heat energy efficiency and a relatively small metal content. To make an experimental check of the operating capability of a plate heat exchanger under ammonia production conditions, a welded plate heat exchanger was designed for an ammonia synthesis column 800mm in diameter. On prolonged testing (four years), the device provided an autothermal operating mode in the column and the heat transfer coefficient was practically constant for fixed space velocities. Consequently, the heat exchange surface was not contaminated significantly with catalyst dust, confirmed by visual observation of the heat exchanger after disassembly.

Obolentsev, Y.G.; Chus', M.S.; Norobchanskii, O.A.; Teplitshi, Y.S.; Tovazhnyanskii, L.L.

1983-01-01T23:59:59.000Z

97

Control and optimal operation of simple heat pump cycles  

E-Print Network [OSTI]

Control and optimal operation of simple heat pump cycles Jørgen Bauck Jensen and Sigurd Skogestad in the opposite direction, the "heat pump", has recently become pop- ular. These two applications have also merged. The coefficients of performance for a heating cycle (heat pump) and a cooling cycle (refrigerator, A/C) are defined

Skogestad, Sigurd

98

Gaines County Solid Waste Management Act (Texas)  

Broader source: Energy.gov [DOE]

This Act establishes the Gaines County Solid Waste Management District, a governmental body to develop and carry out a regional water quality protection program through solid waste management and...

99

Method and apparatus for fuel gas moisturization and heating  

DOE Patents [OSTI]

Fuel gas is saturated with water heated with a heat recovery steam generator heat source. The heat source is preferably a water heating section downstream of the lower pressure evaporator to provide better temperature matching between the hot and cold heat exchange streams in that portion of the heat recovery steam generator. The increased gas mass flow due to the addition of moisture results in increased power output from the gas and steam turbines. Fuel gas saturation is followed by superheating the fuel, preferably with bottom cycle heat sources, resulting in a larger thermal efficiency gain compared to current fuel heating methods. There is a gain in power output compared to no fuel heating, even when heating the fuel to above the LP steam temperature.

Ranasinghe, Jatila (Niskayuna, NY); Smith, Raub Warfield (Ballston Lake, NY)

2002-01-01T23:59:59.000Z

100

Intrinsically irreversible heat engine  

DOE Patents [OSTI]

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

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

1984-12-25T23:59:59.000Z

Note: This page contains sample records for the topic "heat gain coefficient" 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
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101

Intrinsically irreversible heat engine  

DOE Patents [OSTI]

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

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

1984-01-01T23:59:59.000Z

102

Intrinsically irreversible heat engine  

DOE Patents [OSTI]

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

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

1984-01-01T23:59:59.000Z

103

728 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 34, NO. 3, JUNE 2006 The Electron Diffusion Coefficient in Energy  

E-Print Network [OSTI]

Coefficient in Energy in Bounded Collisional Plasmas Lev D. Tsendin Abstract--The electron energies in typical, the momentum relaxation in collisions with neutrals is sig- nificantly faster than the energy relaxation due be de- scribed by a diffusion coefficient in energy . Both collisional and stochastic heating mechanisms

Kaganovich, Igor

104

Method and system for edge cladding of laser gain media  

DOE Patents [OSTI]

A gain medium operable to amplify light at a gain wavelength and having reduced transverse ASE includes an input surface and an output surface opposing the input surface. The gain medium also includes a central region including gain material and extending between the input surface and the output surface along a longitudinal optical axis of the gain medium. The gain medium further includes an edge cladding region surrounding the central region and extending between the input surface and the output surface along the longitudinal optical axis of the gain medium. The edge cladding region includes the gain material and a dopant operable to absorb light at the gain wavelength.

Bayramian, Andrew James; Caird, John Allyn; Schaffers, Kathleen Irene

2014-03-25T23:59:59.000Z

105

Experimental and numerical investigation of turbulent flow and heat (mass) transfer in a two-pass trapezoidal channel with turbulence promoters  

E-Print Network [OSTI]

attached on both the top and bottom walls in parallel sequence. A naphthalene sublimation technique was used, and the heat and mass transfer analogy was applied to convert the mass transfer coefficients to heat transfer coefficients. Numerical predictions...

Oh, Sung Hyuk

2009-05-15T23:59:59.000Z

106

Bunching coefficients in Echo-Enabled Harmonic Generation  

E-Print Network [OSTI]

Coulombian diffusion determines a dilution of bunching coefficients in Free Electron Laser seeded devices. From the mathematical point of view the effect can be modeled through a heat type equation, which can be merged with the ordinary Liouville equation, ruling the evolution of the longitudinal phase space beam distribution. We will show that the use of analytical tools like the Generalized Bessel Functions and algebraic techniques for the solution of evolution problems may provide a useful method of analysis and shine further light on the physical aspects of the underlying mechanisms.

Dattoli, G

2013-01-01T23:59:59.000Z

107

7-117 The claim of a heat pump designer regarding the COP of the heat pump is to be evaluated. Assumptions The heat pump operates steadily.  

E-Print Network [OSTI]

7-47 7-117 The claim of a heat pump designer regarding the COP of the heat pump is to be evaluated. Assumptions The heat pump operates steadily. HP Wnet,in QH QL TL TH Analysis The maximum heat pump coefficient of performance would occur if the heat pump were completely reversible, 5.7 K026K300 K300 COP maxHP, LH H TT

Bahrami, Majid

108

Capital gains tax treatment and the cattleman  

E-Print Network [OSTI]

Major Subject: Agricultural Economics CAPITAL GAINS TAX TREATMENT AND THE CATTLEMAN A Thesis by M I LTDN EDWARD R I STE R Approved as to style and content by: airman o ommi e Dr. Ronald R. Kay Head o D artment Dr. John opkin Mem er Dr. Donald... R. Levi e er Dr. Howard Hesby December 1976 ABSTRACT Capital Gains Tax Treatment and the Catt leman. (December 1976) Milton Edward Rister, B. S. , Texas ASM University Chairman of Advisory Committee: Or. Ronald D. Kay The federal tax...

Rister, M. Edward

1976-01-01T23:59:59.000Z

109

Heat exchanger with ceramic elements  

DOE Patents [OSTI]

An annular heat exchanger assembly includes a plurality of low thermal growth ceramic heat exchange members with inlet and exit flow ports on distinct faces. A mounting member locates each ceramic member in a near-annular array and seals the flow ports on the distinct faces into the separate flow paths of the heat exchanger. The mounting member adjusts for the temperature gradient in the assembly and the different coefficients of thermal expansion of the members of the assembly during all operating temperatures.

Corey, John A. (North Troy, NY)

1986-01-01T23:59:59.000Z

110

Gainful Employment Programs Guidance January 2012  

E-Print Network [OSTI]

with the following information on our GE programs: · Name and Classification of Instructional Program (CIP) code1 Gainful Employment Programs Guidance January 2012 Eric R. Pedersen, Associate Vice Chancellor Background On October 29, 2010, and June 13, 2011, the Department of Education (ED) published final

Pantaleone, Jim

111

Gain International Work Experience in China  

E-Print Network [OSTI]

Gain International Work Experience in China www.StudyCLI.org "The CLI internship gave me a huge boost both personally and professionally. At 21 years old, I've lived in China and can speak basic city of Guilin, China. CLIinternsengageinadynamicrangeofprojects: Y Establishnewrelationshipswith

Virginia Tech

112

Columbia University Opportunities to Gain Experience  

E-Print Network [OSTI]

Columbia University Opportunities to Gain Experience There are myriad ways to build experience Sciences at Columbia University offers on-campus research opportunities for the summer term Dec. 13 - March careereducation.columbia.edu Join LionSHARE ­ CCE's internship/job board Double Discovery Center Volunteer

Shepard, Kenneth

113

Columbia University Opportunities to Gain Experience  

E-Print Network [OSTI]

Columbia University Opportunities to Gain Experience There are so many ways to build experience The Columbia University Office of Government and Community Affairs provides assistance to undergraduates.edu/academics/research/science Summer Undergraduate Research Fellowship The Department of Biological Sciences at Columbia University

Hone, James

114

Columbia University Opportunities to Gain Experience  

E-Print Network [OSTI]

Columbia University Opportunities to Gain Experience There are so many ways to build experience Program The Columbia University Office of Government and Community Affairs provides assistance.edu/academics/research/science Summer Undergraduate Research Fellowship The Department of Biological Sciences at Columbia University

Hone, James

115

APPENDIX H Partition Coefficients For Strontium  

E-Print Network [OSTI]

APPENDIX H Partition Coefficients For Strontium #12;Appendix H Partition Coefficients For Strontium H.1.0 Background Two simplifying assumptions underlying the selection of strontium Kd values included in the look-up table were made. These assumptions are that the adsorption of strontium adsorption

116

APPENDIX J Partition Coefficients For Uranium  

E-Print Network [OSTI]

APPENDIX J Partition Coefficients For Uranium #12;Appendix J Partition Coefficients For Uranium J.1.0 Background The review of uranium Kd values obtained for a number of soils, crushed rock and their effects on uranium adsorption on soils are discussed below. The solution pH was also used as the basis

117

Friction Coefficient for Quarks in Supergravity Duals  

E-Print Network [OSTI]

We study quarks moving in strongly-coupled plasmas that have supergravity duals. We compute the friction coefficient of strings dual to such quarks for general static supergravity backgrounds near the horizon. Our results also show that a previous conjecture on the bound has to be modified and higher friction coefficients can be achieved.

E. Antonyan

2006-11-22T23:59:59.000Z

118

APPENDIX I Partition Coefficients For Thorium  

E-Print Network [OSTI]

APPENDIX I Partition Coefficients For Thorium #12;Appendix I Partition Coefficients For Thorium of thorium Kd values for the look-up table. These assumptions were based on the findings of the literature review conducted on the geochemical processes affecting thorium sorption. The assumptions are as follows

119

Absorption Coefficients and Impedance Daniel A. Russell  

E-Print Network [OSTI]

1 Absorption Coefficients and Impedance Daniel A. Russell Science and Mathematics Department will measure the absorption coefficients and acoustic impedance of samples of acoustic absorbing materials material is responsible for almost 50% of sound absorption inside an automobile). The reverberation time

Russell, Daniel A.

120

U-030: Apache Tomcat Lets Untrusted Web Applications Gain Elevated...  

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

0: Apache Tomcat Lets Untrusted Web Applications Gain Elevated Privileges U-030: Apache Tomcat Lets Untrusted Web Applications Gain Elevated Privileges November 9, 2011 - 8:30am...

Note: This page contains sample records for the topic "heat gain coefficient" 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

Physics 1114: Unit 7 Homework Use the table in your text for specific heat capacity values.  

E-Print Network [OSTI]

at 20 C? [Specific heat capacity of air = 703 J/(kg C ) at constant volume.] 7. What is the specific of a heat engine and a heat pump. Include QH, QC, TH, TC, and W. What is the major difference in your two not the same? 6. Determine the maximum coefficient of performance of a heat pump used to heat the inside

Mansell, Edward "Ted"

122

High Average Power Laser Gain Medium With Low Optical Distortion Using A Transverse Flowing Liquid Host  

DOE Patents [OSTI]

A high average power, low optical distortion laser gain media is based on a flowing liquid media. A diode laser pumping device with tailored irradiance excites the laser active atom, ion or molecule within the liquid media. A laser active component of the liquid media exhibits energy storage times longer than or comparable to the thermal optical response time of the liquid. A circulation system that provides a closed loop for mixing and circulating the lasing liquid into and out of the optical cavity includes a pump, a diffuser, and a heat exchanger. A liquid flow gain cell includes flow straighteners and flow channel compression.

Comaskey, Brian J. (Walnut Creek, CA); Ault, Earl R. (Livermore, CA); Kuklo, Thomas C. (Oakdale, CA)

2005-07-05T23:59:59.000Z

123

Separate effects of surface roughness, wettability and porosity on boiling heat transfer and critical heat flux and optimization of boiling surfaces  

E-Print Network [OSTI]

The separate effects of surface wettability, porosity, and roughness on critical heat flux (CHF) and heat transfer coefficient (HTC) were examined using carefully-engineered surfaces. All test surfaces were prepared on ...

O'Hanley, Harrison Fagan

2012-01-01T23:59:59.000Z

124

Roof Coating Procedures and Their Productivity Gains  

E-Print Network [OSTI]

benefit of the installation of different roof coating technologies and comparable application procedures of these technologies are ambiguous. The focal point of this research is to determine the effective correlation between various commercially... available roof coatings, and productivity gains associated with these energy saving strategies. This type of situation is evidenced in the justification of energy rebates distributed by Florida Power & Light in exchange for the application of Energy Star...

Bonaby, J.; Schaub, D.

2006-01-01T23:59:59.000Z

125

Gaines, Michigan: Energy Resources | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy Resources Jump to: navigation, search Equivalent URIFrontier,JumpGahanna, Ohio: EnergyGaines, Michigan:

126

GainSpan Corporation | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentrating Solar Power Basics (TheEtelligenceGainSpan Corporation Jump to: navigation, search

127

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...

128

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...

129

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...

130

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...

131

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...

132

Transport coefficients of a unitarized pion gas  

E-Print Network [OSTI]

The latest experimental results in relativistic heavy-ion collisions show that the matter there produced requires transport coefficients because of the important collective properties found. We review the theoretical calculation of these transport coefficients in the hadron side at low temperatures by computing them in a gas composed of low energy pions. The interaction of these pions is taken from an effective chiral theory and further requiring scattering unitarity. The propagation of D and D* mesons in the thermalized pion gas is also studied in order to extract the heavy quark diffusion coefficients in the system.

Juan M. Torres-Rincon

2011-11-16T23:59:59.000Z

133

Application of Industrial Heat Improving energy efficiency of  

E-Print Network [OSTI]

compared with Residential Heat Pumps High energy efficiency = high coefficient of performance (COP) (eApplication of Industrial Heat Pumps Improving energy ­ efficiency of industrial processes . H.J. Laue Information Centre on Heat Pumps and Refrigeration IZW e.V. #12;2 Welcome Achema Congress 2012

Oak Ridge National Laboratory

134

Plant physiology Heat of combustion, degree of reduction  

E-Print Network [OSTI]

Plant physiology Heat of combustion, degree of reduction and carbon content: 3 interrelated methods coefficient between heat of combustion and degree of reduction may vary according to the chemical composition parameters in consequence. construction cost / growth yield / heat of combustion / elemental analysis

Paris-Sud XI, Université de

135

Survey of Gain-Scheduling Analysis & Design WE.Leithead  

E-Print Network [OSTI]

ranging from aerospace to process control. Despite the wide application of gain-scheduling controllers of gain-scheduling controllers and a diverse academic literature relating to gain- scheduling extendingSurvey of Gain-Scheduling Analysis & Design D.J.Leith WE.Leithead Department of Electronic

Duffy, Ken

136

Effects of Gain Changes on RPM Performance  

SciTech Connect (OSTI)

The mission of the U.S. Department of Energy/National Nuclear Security Administration's (DOE/NNSA's) Office of the Second Line of Defense (SLD) is to strengthen the capability of foreign governments to deter, detect, and interdict the illicit trafficking of special nuclear and other radioactive materials across international borders and through the global maritime shipping system. The goal of this mission is to reduce the probability of these materials being fashioned into a weapon of mass destruction or radiological dispersal device that could be used against the United States or its international partners. This goal is achieved primarily through the installation and operation of radiation detection equipment at border crossings, airports, seaports, and other strategic locations around the world. In order to effectively detect the movement of radioactive material, the response of these radiation detectors to various materials in various configurations must be well characterized. Oak Ridge National Laboratory (ORNL) investigated two aspects of Radiation Portal Monitor (RPM) settings, based on a preliminary investigation done by the Los Alamos National Laboratory (LANL): source-to-detector distance effect on amplifier gain and optimized discriminator settings. This report discusses this investigation. A number of conclusions can be drawn from the ORNL testing. First, for increased distance between the source and the detector, thus illuminating the entire detector rather than just the center of the detector (as is done during detector alignments), an increase in gain may provide a 5-15% increase in sensitivity (Fig. 4). However, increasing the gain without adjusting the discriminator settings is not recommended as this makes the monitor more sensitive to electronic noise and temperature-induced fluctuations. Furthermore, if the discriminators are adjusted in relation to the increase in gain, thus appropriately discriminating against electronic noise, the sensitivity gains are less than 5% (Fig. 6). ORNL does not consider this slight increase in sensitivity to be a worthwhile pursuit. Second, increasing the ULD will increase sensitivity a few percent (Fig. 7); however, it is not clear that the slight increase in sensitivity is worth the effort required to make the change (e.g., reliability, cost, etc.). Additionally, while the monitor would be more sensitive to HEU, it would also be more sensitive to NORM. Third, the sensitivity of the system remains approximately the same whether it is calibrated to a small source on contact or a large source far away (Fig. 6). This affirms that no changes to the existing calibration procedure are necessary.

Lousteau, Angela L [ORNL; York, Robbie Lynn [ORNL; Livesay, Jake [ORNL

2012-03-01T23:59:59.000Z

137

Using Exergy Analysis Methodology to Assess the Heating Efficiency of an Electric Heat Pump  

E-Print Network [OSTI]

The authors, using exergy analysis methodology, propose that it should consider not only the COP (coefficient of Performance) value of the electric power heat pump set (EPHPS/or HP set), but also the exergy loss at the heating exchanger of the HP...

Ao, Y.; Duanmu, L.; Shen, S.

2006-01-01T23:59:59.000Z

138

Creating materials with a desired refraction coefficient  

E-Print Network [OSTI]

A method is given for creating material with a desired refraction coefficient. The method consists of embedding into a material with known refraction coefficient many small particles of size $a$. The number of particles per unit volume around any point is prescribed, the distance between neighboring particles is $O(a^{\\frac{2-\\kappa}{3}})$ as $a\\to 0$, $0<\\kappa<1$ is a fixed parameter. The total number of the embedded particle is $O(a^{\\kappa-2})$. The physical properties of the particles are described by the boundary impedance $\\zeta_m$ of the $m-th$ particle, $\\zeta_m=O(a^{-\\kappa})$ as $a\\to 0$. The refraction coefficient is the coefficient $n^2(x)$ in the wave equation $[\

A. G. Ramm

2009-09-02T23:59:59.000Z

139

Symmetries and Interaction coefficients of Kelvin waves  

E-Print Network [OSTI]

We considered symmetry restriction on the interaction coefficients of Kelvin waves and demonstrated that linear in small wave vector asymptotic is not forbidden, as one can expect by naive reasoning.

Vladimir V. Lebedev; Victor S. L'vov

2010-05-25T23:59:59.000Z

140

Symmetry energy coefficients for asymmetric nuclear matter  

E-Print Network [OSTI]

Symmetry energy coefficients of asymmetric nuclear matter are investigated as the inverse of nuclear matter polarizabilities with two different approaches. Firstly a general calculation shows they may depend on the neutron-proton asymmetry itself. The choice of particular prescriptions for the density fluctuations lead to certain isospin (n-p asymmetry) dependences of the polarizabilities. Secondly, with Skyrme type interactions, the static limit of the dynamical polarizability is investigated corresponding to the inverse symmetry energy coefficient which assumes different values at different asymmetries (and densities and temperatures). The symmetry energy coefficient (in the isovector channel) is found to increase as n-p asymmetries increase. The spin symmetry energy coefficient is also briefly investigated.

Fábio L. Braghin

2003-12-16T23:59:59.000Z

Note: This page contains sample records for the topic "heat gain coefficient" 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

Heating system  

SciTech Connect (OSTI)

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

Nishman, P.J.

1983-03-08T23:59:59.000Z

142

Gaining Energy Perspective | Department of Energy  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:Year in3.pdf Flash2006-53.pdf0.pdfCost SavingsEnergy GETEMGolden FieldGaining Energy

143

Gaining creative control over semiconductor nanowires  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFun with Big Sky Learning Fun with Big SkyDIII-DRMR LSU/CAMD|Gaining creative

144

Women @ Energy: Linda Gaines | Department of Energy  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-Up from theDepartment of Dept.| WEATHERIZATION5Iski WomenKerstinGaines Women @ Energy:

145

Heat Transfer -1 You are given the following information for a fluid with thermal conductivity of k = 0.0284 W/m-K that  

E-Print Network [OSTI]

Heat Transfer - 1 You are given the following information for a fluid with thermal conductivity the flow is laminar near the wall. a) (30 points) Determine the corresponding heat transfer coefficient the heat transfer coefficient as a function of x. c) (25 points) Determine the average heat transfer

Virginia Tech

146

Computation of Clebsch-Gordan and Gaunt coefficients using binomial coefficients  

SciTech Connect (OSTI)

Using binomial coefficients the Clebsch-Gordan and Gaunt coefficients were calculated for extremely large quantum numbers. The main advantage of this approach is directly calculating these coefficients, instead of using recursion relations. Accuracy of the results is quite high for quantum numbers l{sub 1}, and l{sub 2} up to 100. Despite direct calculation, the CPU times are found comparable with those given in the related literature. 11 refs., 1 fig., 2 tabs.

Guseinov, I.I.; Oezmen, A.; Atav, Ue [Selcuk Univ., Kampus, Konya (Turkey)] [and others] [Selcuk Univ., Kampus, Konya (Turkey); and others

1995-12-01T23:59:59.000Z

147

Industrial heat pumps - types and costs  

SciTech Connect (OSTI)

Confusion about energy savings and economics is preventing many potentially beneficial applications for industrial heat pumps. The variety of heat pumps available and the lack of a standard rating system cause some of this confusion. The authors illustrate how a simple categorization based on coefficient of performance (COP) can compare the cost of recovering waste energy with heat pumps. After evaluating examples in which the cost of energy delivered was calculated based on estimates of capital cost, operating costs, and maintenance costs, they compare heat pumps from the various categories on the basis of economics. 6 references, 6 figures, 1 table.

Chappell, R.N.; Bliem, C.J. Jr.; Mills, J.I.; Demuth, O.J.; Plaster, D.S.

1985-08-01T23:59:59.000Z

148

A new predictive dynamic model describing the effect of1 the ambient temperature and the convective heat transfer2  

E-Print Network [OSTI]

and the convective heat transfer2 coefficient on bacterial growth3 4 H. Ben Yaghlenea,b* , I. Leguerinela , M. Hamdib Ratkowsky "square root" model and a simplified two-parameter20 heat transfer model regarding an infinite air temperature, the convective heat transfer22 coefficient and the growth parameters of the micro

Paris-Sud XI, Université de

149

Experimental and theoretical investigations of microwave heating  

E-Print Network [OSTI]

the variation of the computed time response of the thermocouple with variation of the heat transfer coefficient. It can be seen that the response gets slower as the heat transfer coefficient is decreased and vice versa... and vice versa. Table 4.3 Variation of Time Constant with Diameter of Thermocouple Used Diameter (inch) Time constant(sec) 0.02 1.55 0.022 1.705 0.018 1.395 15 Variation of response with D 0 20 40 60 80 100 120 0 5 10 15 20 25...

Kota, Bhagat Chandra

2004-09-30T23:59:59.000Z

150

Fractal diffusion coefficient from dynamical zeta functions  

E-Print Network [OSTI]

Dynamical zeta functions provide a powerful method to analyze low dimensional dynamical systems when the underlying symbolic dynamics is under control. On the other hand even simple one dimensional maps can show an intricate structure of the grammar rules that may lead to a non smooth dependence of global observable on parameters changes. A paradigmatic example is the fractal diffusion coefficient arising in a simple piecewise linear one dimensional map of the real line. Using the Baladi-Ruelle generalization of the Milnor-Thurnston kneading determinant we provide the exact dynamical zeta function for such a map and compute the diffusion coefficient from its smallest zero.

G. Cristadoro

2005-09-28T23:59:59.000Z

151

ThermalEngineeringLaboratory,VanderbiltUniversity Convection Heat Transfer of Nanofluids in Commercial  

E-Print Network [OSTI]

EngineeringLaboratory,VanderbiltUniversity Experimental Setup Straight Tube Setup Constant Temperature Bath Parastaltic Pump Nanofluid Reservoir Heated.91 od di Commercial System Setup Heater Insulation Water block 4/10 #12;Thermal gain across the heated tube for the DI-water and the 0.5% nanofluid · Greater temperature gain in the 1

Walker, D. Greg

152

LIQUID-FLUIDIZED-BED HEAT' EXCHANGER FLOW DISTRIBUTION MODELS  

Office of Scientific and Technical Information (OSTI)

rods, and shell-side heat transfer coefficients were calculated u s i n g "Newton's Law o f Cooling": a c The horizontal tubes showed a definite angular dependence of the...

153

Gain Scheduled Control Using the Dual Youla Parameterization  

E-Print Network [OSTI]

Stability is a critical issue in gain-scheduled control problems in that the closed loop system may not be stable during the transitions between operating conditions despite guarantees that the gain-scheduled controller stabilizes the plant model...

Chang, Young Joon

2011-08-08T23:59:59.000Z

154

Control and optimal operation of simple heat pump cycles Jrgen B. Jensen and Sigurd Skogestad  

E-Print Network [OSTI]

Control and optimal operation of simple heat pump cycles Jørgen B. Jensen and Sigurd Skogestad cycle. Keywords: Operation, heat pump cycle, cyclic process, charge, self-optimizing control 1. The coefficients of performance for a heating cycle (heat pump) and a cooling cycle (re- frigerator, A

Skogestad, Sigurd

155

Heat Transfer Measurements for a Horizontal Micro-Tube Using Liquid Crystal Thermography  

E-Print Network [OSTI]

62 TC02-007 Heat Transfer Measurements for a Horizontal Micro-Tube Using Liquid Crystal-tube and 1000m micro-tube. In the single-phase heat transfer experiments, the fully-developed flow heat transfer were also measured using thermocouples (TC). The results showed that the heat transfer coefficient

Ghajar, Afshin J.

156

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

157

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

158

TRADE COSTS AND THE GAINS FROM TRADE IN CROP AGRICULTURE  

E-Print Network [OSTI]

costs, trade liberalization. JEL codes: F18, Q17, Q54. Although the theoretical case for the gains from

Tullos, Desiree

159

Design of Gain-Scheduled Strictly Positive Real Controllers  

E-Print Network [OSTI]

Design of Gain-Scheduled Strictly Positive Real Controllers Using Numerical Optimization the linear SPR controllers, which compose the gain-scheduled controller. Second, we formulate the optimization problem associ- ated with the gain-scheduled controller itself. Restricting our in- vestigation

Damaren, Christopher J.

160

Heat Transfer in Underground Rail Tunnels  

E-Print Network [OSTI]

The transfer of heat between the air and surrounding soil in underground tunnels ins investigated, as part of the analysis of environmental conditions in underground rail systems. Using standard turbulent modelling assumptions, flow profiles are obtained in both open tunnels and in the annulus between a tunnel wall and a moving train, from which the heat transfer coefficient between the air and tunnel wall is computed. The radial conduction of heat through the surrounding soil resulting from changes in the temperature of air in the tunnel are determined. An impulse change and an oscillating tunnel air temperature are considered separately. The correlations between fluctuations in heat transfer coefficient and air temperature are found to increase the mean soil temperature. Finally, a model for the coupled evolution of the air and surrounding soil temperature along a tunnel of finite length is given.

Sadokierski, Stefan

2007-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heat gain coefficient" 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

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

162

Hodges residence: performance of a direct gain passive solar home in Iowa  

SciTech Connect (OSTI)

Results are presented for the performance of the Hodges Residence, a 2200-square-foot earth-sheltered direct gain passive solar home in Ames, Iowa, during the 1979-80 heating season, its first occupied season. No night insulation was used on its 500 square feet of double-pane glass. Total auxiliary heat required was 43 GJ (41 MBTU) gross and 26 GJ (25 MBTU) net, amounting, respectively, to 60 and 36 kJ/C/sup 0/-day-m/sup 2/ (2.9 and 1.8 BTU/F/sup 0/-day-ft/sup 2/). The heating season was unusually cloudy and included the cloudiest January in the 21 years of Ames insolation measurements. Results are also presented for the performance of the hollow-core floor which serves as the main storage mass and for the comfort range in the house.

Hodges, L.

1980-01-01T23:59:59.000Z

163

Heat Transfer between Graphene and Amorphous SiO2  

E-Print Network [OSTI]

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

B. N. J. Persson; H. Ueba

2010-07-22T23:59:59.000Z

164

Electric top drives gain wide industry acceptance  

SciTech Connect (OSTI)

Since its introduction, the top drive drilling system has gained acceptance as a productive and safe method for drilling oil and gas wells. Originally, the system was used mostly for offshore and higher cost land drilling, and it had to be installed as a permanent installation because of its enormous weight and size. Essentially, a top drive replaces the kelly and rotary table as the means of rotating drillpipe on oil, gas and geothermal rigs and is considered to be 15% to 40% more efficient than a kelly drive. Top drive systems allow the operator to drill and maintain directional orientation for triple stands and provide tripping efficiency because of the ability to ream and circulate with triple stands, to reduce the risk of stuck pipe or lost wells, and to improve well control and pipe handling safety. The paper describes electric top drives with DC motors, top drives with AC motors, top drives with permanent magnet motors, and top drives with permanent magnet brushless synchronous motors.

Riahi, M.L.

1998-05-01T23:59:59.000Z

165

Heating System Specification Specification of Heating System  

E-Print Network [OSTI]

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

Day, Nancy

166

DHC: a diurnal heat capacity program for microcomputers  

SciTech Connect (OSTI)

A computer program has been developed that can predict the temperature swing in direct gain passive solar buildings. The diurnal heat capacity (DHC) program calculates the DHC for any combination of homogeneous or layered surfaces using closed-form harmonic solutions to the heat diffusion equation. The theory is described, a Basic program listing is provided, and an example solution printout is given.

Balcomb, J.D.

1985-01-01T23:59:59.000Z

167

Green function diagonal for a class of heat equations  

E-Print Network [OSTI]

A construction of the heat kernel diagonal is considered as element of generalized Zeta function, that, being meromorfic function, its gradient at the origin defines determinant of a differential operator in a technique for regularizing quadratic path integral. Some classes of explicit expression in the case of finite-gap potential coefficient of the heat equation are constructed.

Grzegorz Kwiatkowski; Sergey Leble

2011-12-15T23:59:59.000Z

168

Gain properties of dye-doped polymer thin films  

E-Print Network [OSTI]

The demonstration of an electrically pumped organic laser remains a major issue of organic optoelectronics for several decades. Nowadays, hybrid pumping seems a promising compromise where the organic material is optically pumped by an electrically pumped inorganic device on chip. This technical solution requires therefore an optimization of the organic gain medium under optical pumping. Here, we report a detailed study of gain features of dye-doped polymer thin films, in particular we introduce the gain efficiency $K$, in order to facilitate comparison between material and experimental conditions. First, we measure the bulk gain by the means of a pump-probe setup, and then present in details several factors which modify the actual gain of the layer, namely the confinement factor, the pump polarization, the molecular anisotropy, and the re-absorption. The usual model to evaluate the gain leads to an overestimation by more than one order of magnitude, which stresses the importance to design the devices accordin...

Gozhyk, I; Rabbani, H; Djellali, N; Forget, S; Chenais, S; Ulysse, C; Brosseau, A; Gauvin, S; Zyss, J; Lebental, M

2014-01-01T23:59:59.000Z

169

Heat exchanger with transpired, highly porous fins  

DOE Patents [OSTI]

The heat exchanger includes a fin and tube assembly with increased heat transfer surface area positioned within a hollow chamber of a housing to provide effective heat transfer between a gas flowing within the hollow chamber and a fluid flowing in the fin and tube assembly. A fan is included to force a gas, such as air, to flow through the hollow chamber and through the fin and tube assembly. The fin and tube assembly comprises fluid conduits to direct the fluid through the heat exchanger, to prevent mixing with the gas, and to provide a heat transfer surface or pathway between the fluid and the gas. A heat transfer element is provided in the fin and tube assembly to provide extended heat transfer surfaces for the fluid conduits. The heat transfer element is corrugated to form fins between alternating ridges and grooves that define flow channels for directing the gas flow. The fins are fabricated from a thin, heat conductive material containing numerous orifices or pores for transpiring the gas out of the flow channel. The grooves are closed or only partially open so that all or substantially all of the gas is transpired through the fins so that heat is exchanged on the front and back surfaces of the fins and also within the interior of the orifices, thereby significantly increasing the available the heat transfer surface of the heat exchanger. The transpired fins also increase heat transfer effectiveness of the heat exchanger by increasing the heat transfer coefficient by disrupting boundary layer development on the fins and by establishing other beneficial gas flow patterns, all at desirable pressure drops.

Kutscher, Charles F. (Golden, CO); Gawlik, Keith (Boulder, CO)

2002-01-01T23:59:59.000Z

170

Use of a photonic crystal for optical amplifier gain control  

DOE Patents [OSTI]

An optical amplifier having a uniform gain profile uses a photonic crystal to tune the density-of-states of a gain medium so as to modify the light emission rate between atomic states. The density-of-states of the gain medium is tuned by selecting the size, shape, dielectric constant, and spacing of a plurality of microcavity defects in the photonic crystal. The optical amplifier is particularly useful for the regeneration of DWDM signals in long optical fibers.

Lin, Shawn-Yu (Albuquerque, NM); Fleming, James G. (Albuquerque, NM); El-Kady, Ihab (Albuquerque, NM)

2006-07-18T23:59:59.000Z

171

OPTIMIZATION AND DESIGN GUIDELINES FOR HIGH FLUX MICRO-CHANNEL HEAT SINKS FOR LIQUID AND GASEOUS SINGLE-PHASE FLOW  

E-Print Network [OSTI]

forced convection micro-channel heat sinks for minimum pump power at high heat fluxes. Results gained orders of magnitude, especially for high heat flux devices. Using water and air as coolants, designs for heat fluxes of >10 kW/cm2 and >100 W/cm2 respectively with pump/fan power expenses less than 1

Müller, Norbert

172

ORISE: CDC Travelers' Health Mobile App, Designed by ORISE, Gains...  

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

Can I Eat This? Mobile App Helps International Travelers Make Safe Dining Choices CDC Travelers' Health app, designed by ORISE, gains attention on multiple websites How ORISE is...

173

Transport coefficients of a massive pion gas  

E-Print Network [OSTI]

We review or main results concerning the transport coefficients of a light meson gas, in particular we focus on the case of a massive pion gas. Leading order results according to the chiral power-counting are presented for the DC electrical conductivity, thermal conductivity, shear viscosity, and bulk viscosity. We also comment on the possible correlation between the bulk viscosity and the trace anomaly in QCD, as well as the relation between unitarity and a minimum of the quotient $\\eta/s$ near the phase transition.

D. Fernandez-Fraile; A. Gomez Nicola

2009-12-20T23:59:59.000Z

174

Measuring solar reflectance Part I: Defining a metric that accurately predicts solar heat gain  

E-Print Network [OSTI]

of In press at Progress in Solar Energy April 28, 2010 R.and P. Berdahl Measuring solar re?ectance—Part I sunlight2008. In press at Progress in Solar Energy April 28, 2010 R.

Levinson, Ronnen

2010-01-01T23:59:59.000Z

175

Duct Systems in large commercial buildings: Physical characterization, air leakage, and heat conduction gains  

E-Print Network [OSTI]

decreases between cooling coils and supply registers andoutlet of the cooling coils and the supply registers causeddecreased the cooling capacity of the supply air exiting

Fisk, W.J.

2011-01-01T23:59:59.000Z

176

Enhanced two phase flow in heat transfer systems  

DOE Patents [OSTI]

A family of structures and designs for use in devices such as heat exchangers so as to allow for enhanced performance in heat exchangers smaller and lighter weight than other existing devices. These structures provide flow paths for liquid and vapor and are generally open. In some embodiments of the invention, these structures can also provide secondary heat transfer as well. In an evaporate heat exchanger, the inclusion of these structures and devices enhance the heat transfer coefficient of the evaporation phase change process with comparable or lower pressure drop.

Tegrotenhuis, Ward E; Humble, Paul H; Lavender, Curt A; Caldwell, Dustin D

2013-12-03T23:59:59.000Z

177

Geothermal heating  

SciTech Connect (OSTI)

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

Aureille, M.

1982-01-01T23:59:59.000Z

178

Efficiency, Economic and Environmental Assessment of Ground-Source Heat Pumps in  

E-Print Network [OSTI]

1 Efficiency, Economic and Environmental Assessment of Ground-Source Heat Pumps in Central pump (GSP) for heating, cooling and hot water in a Central Pennsylvania residence (namely, the author, the efficiency gain for the ground-source heat pump compared to electricity is 43% for cooling and 81

Blumsack, Seth

179

Optimal Operation of closed cycles for heating and Jrgen B. Jensen Sigurd Skogestad  

E-Print Network [OSTI]

super-heating, pressure, liquid level or valve set-point. Unlike open systems the initial charge applications have also merged together to give a system able to operate in both heating and cooling mode indicates that 33% of the gained heat is addet as electricity. In industrial processes, especially

Skogestad, Sigurd

180

Heat Pipe Embedded AlSiC Plates for High Conductivity - Low CTE Heat Spreaders  

SciTech Connect (OSTI)

Heat pipe embedded aluminum silicon carbide (AlSiC) plates are innovative heat spreaders that provide high thermal conductivity and low coefficient of thermal expansion (CTE). Since heat pipes are two phase devices, they demonstrate effective thermal conductivities ranging between 50,000 and 200,000 W/m-K, depending on the heat pipe length. Installing heat pipes into an AlSiC plate dramatically increases the plate’s effective thermal conductivity. AlSiC plates alone have a thermal conductivity of roughly 200 W/m-K and a CTE ranging from 7-12 ppm/ deg C, similar to that of silicon. An equivalent sized heat pipe embedded AlSiC plate has effective thermal conductivity ranging from 400 to 500 W/m-K and retains the CTE of AlSiC.

Johnson, Matthew (DOE/NNSA Kansas City Plant (United States)); Weyant, J.; Garner, S. (Advanced Cooling Technologies, Inc. (Lancaster, PA (United States)); Occhionero, M. (CPS Technologies Corporation, Norton, MA (United States))

2010-01-07T23:59:59.000Z

Note: This page contains sample records for the topic "heat gain coefficient" 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

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

182

Water and Space Heating Heat Pumps  

E-Print Network [OSTI]

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

Kessler, A. F.

1985-01-01T23:59:59.000Z

183

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...

Ruch, M. A.

1981-01-01T23:59:59.000Z

184

Heating systems for heating subsurface formations  

DOE Patents [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

185

Innovative heat removal structure for power devices -the drift region integrated microchannel cooler  

E-Print Network [OSTI]

Innovative heat removal structure for power devices - the drift region integrated microchannel is approved to be a compact and high-performance solution to deal with the thermal requirements of power devices and modules. This is due to the large heat exchange surface, the high heat transfer coefficient

Boyer, Edmond

186

MHD EFFECTS ON HEAT TRANSFER IN A MOLTEN SALT BLANKET Sergey Smolentsev, Reza Miraghaie, Mohamed Abdou  

E-Print Network [OSTI]

MHD EFFECTS ON HEAT TRANSFER IN A MOLTEN SALT BLANKET Sergey Smolentsev, Reza Miraghaie, Mohamed-mail (Sergey Smolentsev): Sergey@fusion.ucla.edu Heat transfer in closed channel flows of molten salts (MS of the concept is that the flows in the FW channels are turbulent to provide a high heat transfer coefficient

Abdou, Mohamed

187

Heat Transfer Engineering, 28(6):525540, 2007 Copyright C Taylor and Francis Group, LLC  

E-Print Network [OSTI]

Heat Transfer Engineering, 28(6):525­540, 2007 Copyright C Taylor and Francis Group, LLC ISSN: 0145-7632 print / 1521-0537 online DOI: 10.1080/01457630701193906 Heat Transfer Measurements, Flow Pattern Maps, Stillwater, Oklahoma, USA Local heat transfer coefficients and flow parameters were measured for air

Ghajar, Afshin J.

188

Proceedings of the 29th National Heat Transfer Conference of Italy, Politecnico di Torino, Torino, Italy, June 2022, 2011 INTRODUCTION  

E-Print Network [OSTI]

trends are known, no information about the local heat transfer coefficient in the evaporator U.D.) has been brazed on the main tube of the condenser section in order to connect the vacuum/filling valve transducer 20 Copper fitting FLOW PATTERNS AND CORRESPONDING LOCAL HEAT TRANSFER COEFFICIENTS IN A PULSATING

Khandekar, Sameer

189

Heat-driven acoustic cooling engine having no moving parts  

DOE Patents [OSTI]

A heat-driven acoustic cooling engine having no moving parts receives heat from a heat source. The acoustic cooling engine comprises an elongated resonant pressure vessel having first and second ends. A compressible fluid having a substantial thermal expansion coefficient and capable of supporting an acoustic standing wave is contained in the resonant pressure vessel. The heat source supplies heat to the first end of the vessel. A first heat exchanger in the vessel is spaced-apart from the first end and receives heat from the first end. A first thermodynamic element is adjacent to the first heat exchanger and converts some of the heat transmitted by the first heat exchanger into acoustic power. A second thermodynamic element has a first end located spaced-apart from the first thermodynamic element and a second end farther away from the first thermodynamic element than is its first end. The first end of the second thermodynamic element heats while its second end cools as a consequence of the acoustic power. A second heat exchanger is adjacent to and between the first and second thermodynamic elements. A heat sink outside of the vessel is thermally coupled to and receives heat from the second heat exchanger. The resonant pressure vessel can include a housing less than one-fourth wavelength in length coupled to a reservoir. The housing can include a reduced diameter portion communicating with the reservoir.

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

1989-01-01T23:59:59.000Z

190

THE CORRELATION COEFFICIENTS A generalized method of defining and interpreting correlation coefficients is given. Seven  

E-Print Network [OSTI]

on the ranks of the data. A quick calculation of the rank based correlation coefficients using a 0-1 "graph effect so that they will tend to be small and the net effect is that the covariance will be large. One and the covariance will fluctuate around zero. When there is negative correlation the "distance" from positive

Gideon, Rudy A.

191

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, P.J.

1983-12-08T23:59:59.000Z

192

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

193

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

E-Print Network [OSTI]

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

Bahrami, Majid

194

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

195

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

196

Review of health and productivity gains from better IEQ  

SciTech Connect (OSTI)

The available scientific data suggest that existing technologies and procedures can improve indoor environmental quality (IEQ) in a manner that significantly increases productivity and health. While there is considerable uncertainty in the estimates of the magnitudes of productivity gains that may be obtained, the projected gains are very large. For the U.S., the estimated potential annual savings and productivity gains are $6 to $14 billion from reduced respiratory disease, $2 to $4 billion from reduced allergies and asthma, $10 to $30 billion from reduced sick building syndrome symptoms, and $20 to $160 billion from direct improvements in worker performance that are unrelated to health. Productivity gains that are quantified and demonstrated could serve as a strong stimulus for energy efficiency measures that simultaneously improve the indoor environment.

Fisk, William J.

2000-08-01T23:59:59.000Z

197

Gain scheduling for geometrically nonlinear flexible space structures  

E-Print Network [OSTI]

A gain-scheduling approach for the control of geometrically nonlinear structures is developed. The objective is to improve performance over current linear design techniques that are applied to the same control problem. The ...

Yung, Jeremy Hoyt, 1971-

2002-01-01T23:59:59.000Z

198

Optical Filter Design: Gain Analysis and Tolerance Analysis  

E-Print Network [OSTI]

OPTICAL FILTER DESIGN: GAIN ANALYSIS AND TOLERANCE ANALYSIS A Thesis by VIVEK VANDRASI Submitted to the O ce of Graduate Studies of Texas A&M University in partial ful llment of the requirements for the degree of MASTER OF SCIENCE August... 2010 Major Subject: Electrical Engineering OPTICAL FILTER DESIGN: GAIN ANALYSIS AND TOLERANCE ANALYSIS A Thesis by VIVEK VANDRASI Submitted to the O ce of Graduate Studies of Texas A&M University in partial ful llment of the requirements...

Vandrasi, Vivek

2011-10-21T23:59:59.000Z

199

Industrial heat pumps: types and costs  

SciTech Connect (OSTI)

Many potentially beneficial applications for industrial heat pumps are not being pursued because of confusion regarding both energy savings and economics. Part of this confusion stems from the variety of heat pumps available and the fact that the measure of merit, the coefficient of performance (COP), is commonly defined in at least three different ways. In an attempt to circumvent this problem, a simple categorization was developed based on the commonly accepted COP definitions. Using this categorization, the cost of recovering waste energy with heat pumps was examined. Examples were evaluated in which the cost of energy delivered was calculated based on estimates of capital cost, operating costs, and maintenance costs. Heat pumps from the various categories were then compared on the basis of economics.

Chappell, R.N.; Bliem, C.J. Jr.; Mills, J.I.; Demuth, O.J.; Plaster, D.S.

1985-03-01T23:59:59.000Z

200

Industrial heat pumps - types and costs  

SciTech Connect (OSTI)

Many potentially beneficial applications for industrial heat pumps are not being pursued because of confusion regarding both energy savings and economics. Part of this confusion stems from the variety of heat pumps available and the fact that the measure of merit, the coefficient of performance (COP) is commonly defined in at least three different ways. In an attempt to circumvent this problem, a simple categorization was developed based on the commonly accepted COP definitions. Using this categorization, the cost of recovering waste energy with heat pumps was examined. Examples were evaluated in which the cost of energy delivered was calculated based on estimates of capital cost, operating costs, and maintenance costs. Heat pumps from the various categories were then compared on the basis of economics. 6 refs., 7 figs.

Chappell, R.N.; Bliem, C.J. Jr.; Mills, J.I.; Demuth, O.J.; Plaster, D.S.

1985-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heat gain coefficient" 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

additional net gain: Topics by E-print Network  

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

of contaminants discharged dispersion coefficient to be 70.1 ( 4.3 m2 s-1. Temporal evolution of the SF6 inventory indicates an average Ho, David 369 Building Bayes Nets with...

202

M. Bahrami ENSC 388 Assignment # 9 1 Assignment #9 (Local Heat Transfer Coefficient)  

E-Print Network [OSTI]

flow 0.664 / / 2 0.037 / 871 / 0.664 / 0.032 / 435 Since ReL 5 solution, it follows that ReL 3.2 Ã? 105 Case b): For mixed flow on both plates 0.037 / 871 / 2 0.037 / 871 / 0.037 / 871 0.032 / 435 1.5 10 Note that it is impossible to satisfy the requirement that hL = h2L

Bahrami, Majid

203

Calculation of eddy exchange coefficients for heat and salt from BOMEX data  

E-Print Network [OSTI]

with wind speed. Francis proposes that for intermediate wind speeds, C = . 13 x 10 W so that D (35) becomes . 13x10 p . W air -3 Neumann and Pierson (1966) suggest that C = 9. 0 x 10 D 27 ?, 5 -1 W ' where W is expressed in m sec . According to them... o than an equation proposed by Thorade (1914), 1. 26 W 0 ~sin g (34) Durst obtained relationship (33) by measuring a ship's drift and the wind speed and direction. 3'effreys (1920) derived the formula for K, K = 5 x 10 W4 W cosecg, where W...

Carnes, Michael Ryan

2012-06-07T23:59:59.000Z

204

Effects of slitted fins on the heat transfer and pressure drop characteristics of a compact heat exchanger  

SciTech Connect (OSTI)

A compact heat exchanger which consists of air-cooled aluminum fins and copper tubes circulating refrigerant has been used in a cooling system for a long time. There are two key parameters to be seriously considered for a design of the heat exchanger and its performance improvement. These are the heat transfer rate and pressure drop coefficient which varies with the change of the tube size, its arrangement and the fin configuration. In here, a numerical study was carried to understand the effect of the fin configuration on the heat transfer and pressure drop of the heat exchanger. The diameter and the arrangement of tubes were fixed but three different types of the fin configuration were used to see its effect on the heat transfer capacity and the static pressure drop. The calculation results were compared with that of a flat plate fin. From the comparison, it was found that the slitted fins have higher pressure drop; however, they have higher heat transfer rate. It means that the simpler of the fin configuration, the lower pressure drop and heat transfer coefficients are obtained. It is mainly due to the discretisation of the thermal boundary layer on the fin surface to maximize the heat transfer to air. The slitted sides of fins act like obstacles in the airflow path. From the experimental result, it was found that the same trend in the variation of the heat transfer rate and the pressure drop with the change of the fin configuration was obtained.

Kim, C.H.; Yun, J.Y. [LG Electronics Living System Research Lab., Seoul (Korea, Republic of)

1996-12-31T23:59:59.000Z

205

The Role of the Consultant in Marketing Industrial Heat Pumps  

E-Print Network [OSTI]

device that serves a process heating load or provides space heating for relatively large loads in an in dustrial plant or complex. A heat pump is typi cally driven by electric motors ranging from 25 kW up to several thousand kW motor input power... considered for development and conunercialization, but few of these have been placed in service in the United States. Process heat recovery designs have been installed with electrical inputs of more than 10,000 kW and with coefficients of performance...

Gilbert, J. S.; Niess, R. C.

206

Can fusion coefficients be calculated from the depth rule ?  

E-Print Network [OSTI]

The depth rule is a level truncation of tensor product coefficients expected to be sufficient for the evaluation of fusion coefficients. We reformulate the depth rule in a precise way, and show how, in principle, it can be used to calculate fusion coefficients. However, we argue that the computation of the depth itself, in terms of which the constraints on tensor product coefficients is formulated, is problematic. Indeed, the elements of the basis of states convenient for calculating tensor product coefficients do not have a well-defined depth! We proceed by showing how one can calculate the depth in an `approximate' way and derive accurate lower bounds for the minimum level at which a coupling appears. It turns out that this method yields exact results for $\\widehat{su}(3)$ and constitutes an efficient and simple algorithm for computing $\\widehat{su}(3)$ fusion coefficients.

A. N. Kirillov; P. Mathieu; D. Senechal; M. Walton

1992-09-28T23:59:59.000Z

207

Construction of operator product expansion coefficients via consistency conditions  

E-Print Network [OSTI]

In this thesis an iterative scheme for the construction of operator product expansion (OPE) coefficients is applied to determine low order coefficients in perturbation theory for a specific toy model. We use the approach to quantum field theory proposed by S. Hollands [arXiv:0802.2198], which is centered around the OPE and a number of axioms on the corresponding OPE coefficients. This framework is reviewed in the first part of the thesis. In the second part we apply an algorithm for the perturbative construction of OPE coefficients to a toy model: Euclidean $\\varphi^6$-theory in 3-dimensions. Using a recently found formulation in terms of vertex operators and a diagrammatic notation in terms of trees [arXiv:0906.5313v1], coefficients up to second order are constructed, some general features of coefficients at arbitrary order are presented and an exemplary comparison to the corresponding customary method of computation is given.

Jan Holland

2009-06-30T23:59:59.000Z

208

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

209

Inversion of Robin coefficient by a spectral stochastic finite element approach  

SciTech Connect (OSTI)

This paper investigates a variational approach to the nonlinear stochastic inverse problem of probabilistically calibrating the Robin coefficient from boundary measurements for the steady-state heat conduction. The problem is formulated into an optimization problem, and mathematical properties relevant to its numerical computations are investigated. The spectral stochastic finite element method using polynomial chaos is utilized for the discretization of the optimization problem, and its convergence is analyzed. The nonlinear conjugate gradient method is derived for the optimization system. Numerical results for several two-dimensional problems are presented to illustrate the accuracy and efficiency of the stochastic finite element method.

Jin Bangti [Department of Mathematics, Chinese University of Hong Kong, Shatin, N.T., Hong Kong (China)], E-mail: kimbtsing@yahoo.com.cn; Zou Jun [Department of Mathematics, Chinese University of Hong Kong, Shatin, N.T., Hong Kong (China)], E-mail: zou@math.cuhk.edu.hk

2008-03-01T23:59:59.000Z

210

Economical Route to Produce High Seebeck Coefficient Calcium Cobaltate for Bulk Thermoelectric Applications  

SciTech Connect (OSTI)

Phase pure calcium cobaltate (Ca1.24Co1.62O3.86) was prepared by Self-propagating High-temperature Synthesis (SHS) followed by a short post heat treatment. Prepared powders were characterized by XRD for phase purity, and SEM for particle size and distribution. Temperature histories at the center and on the surface of reaction pellet during the SHS process were monitored and recorded. Particles size of synthesized powders was reduced using a planetary mill to increase its specific surface area. Electrical conductivity, thermal conductivity and Seebeck coefficient of the prepared power were measured and figure of merit was reported.

Selig, Jiri [Lamar University; Lin, Sidney [Lamar University; Lin, Hua-Tay [ORNL; Johnson, D Ray [ORNL; Wang, Hsin [ORNL

2011-01-01T23:59:59.000Z

211

An experimental investigation of turbine blade heat transfer and turbine blade trailing edge cooling  

E-Print Network [OSTI]

studies have investigated the fluid flow and heat transfer behavior in high Reynolds number flows. Blair [7,8] investigated the effect of grid generated turbulence on flat plate heat transfer. He showed that turbulent heat transfer coefficient in flow... AN EXPERIMENTAL INVESTIGATION OF TURBINE BLADE HEAT TRANSFER AND TURBINE BLADE TRAILING EDGE COOLING A Dissertation by JUNGHO CHOI Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment...

Choi, Jungho

2005-02-17T23:59:59.000Z

212

Heat transfer in the trailing edge cooling channels of turbine blades  

E-Print Network [OSTI]

Foundation and from the funded research contract (RF5810) through Dr. Han. NOMENCLATURE A area of heat transfer in the pin fin channel AI, area of heat transfer in the long ejection segments Az cross-sectional area, of trailing edge ejection holes A..., ?minimum flow cross-sectional area in the pin fin channel C'~ discharge coefficient Cp specific heat of air 1 diameter of trailing edge ejection holes D diameter of pins f overall friction factor h?heat transfer coefficient in the n th segment...

Kumaran, T. K.

1989-01-01T23:59:59.000Z

213

RADIATIVE HEATING OF THE SOLAR CORONA  

SciTech Connect (OSTI)

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

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

2011-10-20T23:59:59.000Z

214

Local heat transfer distribution in a triangular channel with smooth walls and staggered ejection holes  

E-Print Network [OSTI]

Transient liquid crystal experiments have been conducted to determine the distribution of the local heat transfer coefficient in a triangular channel with smooth wails and ejection holes along one or two of the wails. The end of the test channel...

Moon, Sung-Won

1999-01-01T23:59:59.000Z

215

The influence of return bends on the downstream pressure drop and condensation heat transfer in tubes  

E-Print Network [OSTI]

The influence of return bends on the downstream pressure drop and heat transfer coefficient of condensing refrigerant R-12 was studied experimentally. Flow patterns in glass return bends of 1/2 to 1 in. radius and 0.315 ...

Traviss, Donald P.

1971-01-01T23:59:59.000Z

216

Home Heating Systems Design using PHP and MySQL Databases  

E-Print Network [OSTI]

This paper presents the use of a computer application based on a MySQL database, managed by PHP programs, allowing the selection of a heating device using coefficient-based calculus.

Karnyanszky, Tiberiu Marius

2009-01-01T23:59:59.000Z

217

accurate rate coefficients: Topics by E-print Network  

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

constant and the diffusion coefficient from molecular dynamics simulations: the case of SPCE water Condensed Matter (arXiv) Summary: The effect of the applied trajectory length...

218

Diffusion coefficient of three-dimensional Yukawa liquids  

SciTech Connect (OSTI)

The purpose of this work is an investigation of the diffusion coefficient of the dust component in complex plasma. The computer simulation of the Yukawa liquids was made on the basis of the Langevin equation, which takes into account the influence of buffer plasma on the dust particles dynamics. The Green–Kubo relation was used to calculate the diffusion coefficient. Calculations of the diffusion coefficient for a wide range of the system parameters were performed. Using obtained numerical data, we constructed the interpolation formula for the diffusion coefficient. We also show that the interpolation formula correctly describes experimental data obtained under microgravity conditions.

Dzhumagulova, K. N.; Ramazanov, T. S.; Masheeva, R. U. [IETP, Al Farabi Kazakh National University, 71, al Farabi ave., Almaty 050040 (Kazakhstan)] [IETP, Al Farabi Kazakh National University, 71, al Farabi ave., Almaty 050040 (Kazakhstan)

2013-11-15T23:59:59.000Z

219

ar diffusion coefficient: Topics by E-print Network  

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

diffusion is examined. Kazuhiko Seki; Saurabh Mogre; Shigeyuki Komura 2014-02-05 4 Fractal diffusion coefficient from dynamical zeta functions Nonlinear Sciences (arXiv)...

220

axial diffusion coefficient: Topics by E-print Network  

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

diffusion is examined. Kazuhiko Seki; Saurabh Mogre; Shigeyuki Komura 2014-02-05 5 Fractal diffusion coefficient from dynamical zeta functions Nonlinear Sciences (arXiv)...

Note: This page contains sample records for the topic "heat gain coefficient" 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

Investigation of gain kinetics in a CO gas dynamic laser  

SciTech Connect (OSTI)

A detailed experimental investigation of small-signal gain in a CO gasdynamic laser, produced in a shock tunnel is presented. Gains of the P/sub 7/(3) transition were measured at a distance 44 cm downstream from the nozzle throat for various CO--Ar and CO--N/sub 2/--Ar mixtures at stagnation temperatures of 1800/sup 0/--3800 /sup 0/K and stagnation pressures of 18--40 atm. Optimum gas temperatures and compositions were observed. Laser oscillations were observed simultaneously in two cavities located at 44 and 56 cm downstream from the nozzle throat. The experimental data on gain have been compared with a numerical model. A quantitatively good argeement between calculations and experiments was found which permits the utilization of the mathematical model for a better understanding of the processes involved in the laser operation. Small signal gains and multi-line laser power outputs were calculated along the nozzle for various initial conditions. Calculations indicate that maximum gain and maximum power occur for P/sub 3/(4)-P/sub 5/(4) lines at a stagnation temperature of about 3000 /sup 0/K and a gas composition of CO:Ar = 20:80.

Stricker, J.; Tilleman, M.

1982-06-01T23:59:59.000Z

222

Two Savannah River Site Projects Gain National Recognition |...  

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

SRNL identified and tested technology to remove tritium from contaminated concrete and soil by using a high heat source called a "thermal detritiation unit." Each unit is a...

223

Combined Heat and Power, Waste Heat, and District Energy | Department...  

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

Combined Heat and Power, Waste Heat, and District Energy Combined Heat and Power, Waste Heat, and District Energy Presentation-given at the Fall 2011 Federal Utility Partnership...

224

Project Profile: Heat Transfer and Latent Heat Storage in Inorganic...  

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

Heat Transfer and Latent Heat Storage in Inorganic Molten Salts for CSP Plants Project Profile: Heat Transfer and Latent Heat Storage in Inorganic Molten Salts for CSP Plants...

225

Pagosa Springs District Heating District Heating Low Temperature...  

Open Energy Info (EERE)

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

226

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...

227

Midland District Heating District Heating Low Temperature Geothermal...  

Open Energy Info (EERE)

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

228

San Bernardino District Heating District Heating Low Temperature...  

Open Energy Info (EERE)

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

229

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...

230

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

231

Locating Heat Recovery Opportunities  

E-Print Network [OSTI]

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

Waterland, A. F.

1981-01-01T23:59:59.000Z

232

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

233

Information Gain Based Dimensionality Selection for Classifying Text Documents  

SciTech Connect (OSTI)

Selecting the optimal dimensions for various knowledge extraction applications is an essential component of data mining. Dimensionality selection techniques are utilized in classification applications to increase the classification accuracy and reduce the computational complexity. In text classification, where the dimensionality of the dataset is extremely high, dimensionality selection is even more important. This paper presents a novel, genetic algorithm based methodology, for dimensionality selection in text mining applications that utilizes information gain. The presented methodology uses information gain of each dimension to change the mutation probability of chromosomes dynamically. Since the information gain is calculated a priori, the computational complexity is not affected. The presented method was tested on a specific text classification problem and compared with conventional genetic algorithm based dimensionality selection. The results show an improvement of 3% in the true positives and 1.6% in the true negatives over conventional dimensionality selection methods.

Dumidu Wijayasekara; Milos Manic; Miles McQueen

2013-06-01T23:59:59.000Z

234

The transfer of heat and mass to a vertical plate under frosting conditions  

E-Print Network [OSTI]

THE TRAESFPIR OF HEAT . 'ND NASH 10 A VERTICAL PLATE UNDER FROSTING CONDITIONS A Thesis Louis Joseph Poth, Jr. Submitted to the Graduate School of the Agricultural and Nechanioal College of Texas in partial fulfili ment of the requirements... of the Husselt-Grashof correlation for heat transfer. coefficient of saturation temper ture and concen- tration gradient correlation, for small temper- ature difference. ooefficient of frost specific gravity-thermal oonductivity correlation. coefficient...

Poth, Louis Joseph

1960-01-01T23:59:59.000Z

235

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

236

Quantum heat engines and refrigerators: Continuous devices  

E-Print Network [OSTI]

Quantum thermodynamics supplies a consistent description of quantum heat engines and refrigerators up to the level of a single few level system coupled to the environment. Once the environment is split into three;a hot, cold and work reservoirs a heat engine can operate. The device converts the positive gain into power;where the gain is obtained from population inversion between the components of the device. Reversing the operation transforms the device into a quantum refrigerator. The quantum tricycle, a device connected by three external leads to three heat reservoirs is used as a template for engines and refrigerators. The equation of motion for the heat currents and power can be derived from first principle. Only a global description of the coupling of the device to the reservoirs is consistent with the first and second laws of thermodynamics. Optimisation of the devices leads to a balanced set of parameters where the couplings to the three reservoirs are of the same order and the external driving field is in resonance. When analysing refrigerators special attention is devoted to a dynamical version of the third law of thermodynamics. Bounds on the rate of cooling when approaching the absolute zero are obtained by optimising the cooling current. At low temperature all refrigerators show universal behavior. Restrictions on the system imposed by the dynamical version of the third law are studied.

Ronnie Kosloff; Amikam Levy

2013-10-02T23:59:59.000Z

237

High-frequency absorption and gain in superlattices: Semiquasistatic approach  

E-Print Network [OSTI]

We consider a generation and an amplification of THz radiation in semiconductor superlattices under the action of microwave pump field. Electrons belonging to a single miniband of the superlattice interact quasistatically with the pump field and dynamically with a signal THz field. Within this semiquasistic approach we derive elegant difference formulas describing absorption (gain) of the weak THz signal. We present an instructive geometric interpretation of the absorption formulas which allows a search of optimum conditions for the gain employing only a simple qualitative analysis. Our theoretical findings contribute to the development of sources and detectors of THz radiation that are using nonlinear electric properties of semiconductor superlattices.

A. V. Shorokhov; K. N. Alekseev

2006-02-08T23:59:59.000Z

238

Total Space Heat-  

Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

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

239

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...

240

Towards Intelligent District Heating.  

E-Print Network [OSTI]

??A district heating system consists of one or more production units supplying energy in the form of heated water through a distribution pipe network to… (more)

Johansson, Christian

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heat gain coefficient" 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

Winter Heating Fuels Update  

Gasoline and Diesel Fuel Update (EIA)

Heating Fuels Update For: Congressional Briefings October 20, 2014 | Washington, DC By U.S. Energy Information Administration Winter Heating Fuels Update October 20, 2014 |...

242

Equilibrium interfacial free energies and Turnbull coefficient for bcc crystallizing colloidal charged sphere suspensions  

E-Print Network [OSTI]

We extend previous analysis of data for the melt-nucleus interfacial free energy, $\\gamma$, gained from optical experiments on suspensions of charged colloidal spheres, which crystallize with body centred cubic (bcc) crystal structures. Compiling data from five pure species with different polydispersities and one binary mixture, we find the equilibrium melt-crystal interfacial energy to be considerably larger than the hard sphere reference value. Both this quantity and the entropy of freezing decrease with increasing polydispersity. Moreover, we give a first experimental determination of the Turnbull coefficient for a bcc crystallizing material. The observed value $C_{T, bcc} \\approx 0.3$ agrees well with theoretical expectations for bcc systems with short to medium ranged interactions.

Thomas Palberg; Patrick Wette; Dieter M. Herlach

2014-03-25T23:59:59.000Z

243

FREQUENCY DEPENDENT ULTRASONIC ATTENUATION COEFFICIENT ASSESSMENT IN FRESH  

E-Print Network [OSTI]

dependency of the ultrasonic attenuation coefficient ranges from f * e to fl.3 6 and its magnitude at 1 MHz dependent attenuation coefficient must be described by a higher ordered function than a simple power fit at the Bioacoustics Research Laboratory (2). A system block diagram appears in Figure 1. CHART ATTENUATOR ALU Ml

Illinois at Urbana-Champaign, University of

244

The effective pyroelectric and thermal expansion coefficients of ferroelectric ceramics  

E-Print Network [OSTI]

The effective pyroelectric and thermal expansion coefficients of ferroelectric ceramics JiangYu Li an estimate on the effective pyroelectric and thermal expansion coefficients of fer- roelectric ceramics, and thermal-medical diagnostics (Cross, 1993). A ceramic made of pyroelectric grains does not necessarily

Li, Jiangyu

245

Micro- and macroscale coefficients of friction of cementitious materials  

SciTech Connect (OSTI)

Millions of metric tons of cementitious materials are produced, transported and used in construction each year. The ease or difficulty of handling cementitious materials is greatly influenced by the material friction properties. In the present study, the coefficients of friction of cementitious materials were measured at the microscale and macroscale. The materials tested were commercially-available Portland cement, Class C fly ash, and ground granulated blast furnace slag. At the microscale, the coefficient of friction was determined from the interaction forces between cementitious particles using an Atomic Force Microscope. At the macroscale, the coefficient of friction was determined from stresses on bulk cementitious materials under direct shear. The study indicated that the microscale coefficient of friction ranged from 0.020 to 0.059, and the macroscale coefficient of friction ranged from 0.56 to 0.75. The fly ash studied had the highest microscale coefficient of friction and the lowest macroscale coefficient of friction. -- Highlights: •Microscale (interparticle) coefficient of friction (COF) was determined with AFM. •Macroscale (bulk) COF was measured under direct shear. •Fly ash had the highest microscale COF and the lowest macroscale COF. •Portland cement against GGBFS had the lowest microscale COF. •Portland cement against Portland cement had the highest macroscale COF.

Lomboy, Gilson [Department of Civil, Construction, and Environmental Engineering, Iowa State University, Ames, IA 50011 (United States)] [Department of Civil, Construction, and Environmental Engineering, Iowa State University, Ames, IA 50011 (United States); Sundararajan, Sriram, E-mail: srirams@iastate.edu [Department of Mechanical Engineering, Iowa State University, Ames, IA 50011 (United States)] [Department of Mechanical Engineering, Iowa State University, Ames, IA 50011 (United States); Wang, Kejin [Department of Civil, Construction, and Environmental Engineering, Iowa State University, Ames, IA 50011 (United States)] [Department of Civil, Construction, and Environmental Engineering, Iowa State University, Ames, IA 50011 (United States)

2013-12-15T23:59:59.000Z

246

METHODS PAPER Addressing Practical Challenges of Low Friction Coefficient  

E-Print Network [OSTI]

sensitive to the lubrication, environment, and contact conditions, and under nominally constant conditions Tribol Trans ASME 127:673­678, 2005), ``...the measurement of friction coefficient is extremely sensitive, friction coefficients range from about 0.2 to 1 for typical material pairs under standard conditions

Sawyer, Wallace

247

Defining the coupling coefficient for electrodynamic transducers Shuo Chenga)  

E-Print Network [OSTI]

-density permanent magnets4 has enabled more com- pact and powerful electrodynamic transducers.5 More recentlyDefining the coupling coefficient for electrodynamic transducers Shuo Chenga) and David P. Arnold September 2013) This paper provides a simple, practical definition of the coupling coefficient

Allen, Jont

248

Heat transfer and film cooling with steam injection  

E-Print Network [OSTI]

for both coolants was determined for similar blowing rates and was used as a basis for comparisons. Heat transfer coefficients were calcula- ted from the experimental data using a transient analysis. DEDICATION To my wife and family. ACKNOWLEDGEMENTS... LIST OF TABLES PAGE TABLE 1 Variation in the Blowing Rate ------------ 55 TABLE 2 TABLE 3 Typical Air Film Cooling Effectiveness Data Typical Steam Film Cooling Effectiveness Data 62 62 1X LIST OF FIGURES PAGE Figure 1 Comparison of Heat...

Conklin, Gary Eugene

1982-01-01T23:59:59.000Z

249

Comparative Performance of Heat Pumps and R&D Requirements  

E-Print Network [OSTI]

in a role of both increasing the process effi ciencies and recovering and reusing waste energy emitted in industrial manufacturing processes. The lead laboratories doing research in heat pumps in the U.S. are the Oak Ridge National Laboratory (ORNL... that have low-film heat and mass transfer coefficients, be able to operate at high temperatures if needed, operate within reasonable pressure limits, be stable, non-toxic, and above all, inexpensive. The program at ORNL addresses these issues...

Ally, M. R.

250

Augmentation of condensation heat transfer with electrohydrodynamics on vertical enhanced tubes  

E-Print Network [OSTI]

for various heat loads . 48 . 49 . 58 NOMENCLATURE cr D ha k Nu qual Re V area, m', or current, A specific heat at constant pressure, J/kgK diameter, m electric field strength, V/m gravity, (9. 81 m/s') heat transfer coefficient, W... fluorocarbon or a hydrocarbon, the temperature of heat addition from the primary fluid to the secondary working fluid tends to be lower, thereby increasing the amount of heat rejected. In many cases the waste heat can be rejected through a condensation...

Motte, Edouard

1994-01-01T23:59:59.000Z

251

Proceedings of the 21st National and 10th ISHMT-ASME Heat and Mass Transfer conference, December 27-30, 2011, IIT Madras, India.  

E-Print Network [OSTI]

visualized. The local heat transfer coefficient in the evaporator zone as well as the overall thermal. Appreciable difference has not been observed in the two cases, maximum heat transfer coefficient being ~ 4600/filling valve (M/s Upchurch Scientific® ). A pressure transducer (Swagelok® , PTI-S-AC5-12AS) is plugged

Khandekar, Sameer

252

Normality of Monte Carlo criticality eigenfunction decomposition coefficients  

SciTech Connect (OSTI)

A proof is presented, which shows that after a single Monte Carlo (MC) neutron transport power method iteration without normalization, the coefficients of an eigenfunction decomposition of the fission source density are normally distributed when using analog or implicit capture MC. Using a Pearson correlation coefficient test, the proof is corroborated by results from a uniform slab reactor problem, and those results also suggest that the coefficients are normally distributed with normalization. The proof and numerical test results support the application of earlier work on the convergence of eigenfunctions under stochastic operators. Knowledge of the Gaussian shape of decomposition coefficients allows researchers to determine an appropriate level of confidence in the distribution of fission sites taken from a MC simulation. This knowledge of the shape of the probability distributions of decomposition coefficients encourages the creation of new predictive convergence diagnostics. (authors)

Toth, B. E.; Martin, W. R. [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, 2355 Bonisteel Boulevard, Ann Arbor, MI 48109 (United States); Griesheimer, D. P. [Bechtel Bettis, Inc., P.O. Box 79, West Mifflin, PA 15122 (United States)

2013-07-01T23:59:59.000Z

253

Is the Gini coefficient a stable measure of galaxy structure?  

E-Print Network [OSTI]

The Gini coefficient, a non-parametric measure of galaxy morphology, has recently taken up an important role in the automated identification of galaxy mergers. I present a critical assessment of its stability, based on a comparison of HST/ACS imaging data from the GOODS and UDF surveys. Below a certain signal-to-noise level, the Gini coefficient depends strongly on the signal-to-noise ratio, and thus becomes useless for distinguishing different galaxy morphologies. Moreover, at all signal-to-noise levels the Gini coefficient shows a strong dependence on the choice of aperture within which it is measured. Consequently, quantitative selection criteria involving the Gini coefficient, such as a selection of merger candidates, cannot always be straightforwardly applied to different datasets. I discuss whether these effects could have affected previous studies that were based on the Gini coefficient, and establish signal-to-noise limits above which measured Gini values can be considered reliable.

Thorsten Lisker

2008-07-09T23:59:59.000Z

254

E-Print Network 3.0 - active life gained Sample Search Results  

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

ues. Inverting Gain As with voltage-feedback op amps, the ratio of the feedback... resistor to the gain-setting resistor determines the voltage gain in current-feedback op amp...

255

Reliability Gain of Network Coding in Lossy Wireless Networks  

E-Print Network [OSTI]

Reliability Gain of Network Coding in Lossy Wireless Networks Majid Ghaderi Department of Computer that network coding improves network reliability by reducing the number of packet retransmissions in lossy networks. However, the extent of the reliability benefit of network coding is not known. This paper

Massachusetts at Amherst, University of

256

Design of a variable gain amplifier for an ultrawideband receiver  

E-Print Network [OSTI]

and the analog VGA is formed by a digital-to-analog converter and an exponential voltage generator. The gain of the VGA varies dB-linearly from 0 to 52 dB with respect to the control voltage. The VGA is operated in open loop with a bandwidth greater than 500 MHz...

Krishnanji, Sivasankari

2005-11-01T23:59:59.000Z

257

1 INTRODUCTION Alternative energy sources have increasingly gained  

E-Print Network [OSTI]

1 INTRODUCTION Alternative energy sources have increasingly gained the interest for governments it is required, is a major concern for alternative energy systems. Profits and environmental benefits, research institutes, academia, and industry in order to advance the penetration of sustainable energy

Sandborn, Peter

258

Gain effect waveguide optical amplifiers for Si microphotonics  

E-Print Network [OSTI]

(cont.) Er-based gain. We reported the first infrared photoluminescence PL study of Er?O? and found a 7 ms lifetime at 4 K, attributed to a metastable FCC or HCP phase. We showed the thermodynamically stable BCC crystal ...

Saini, Sajan, 1973-

2004-01-01T23:59:59.000Z

259

Extractive Institutions and Gains From Trade: Evidence from Colonial Africa  

E-Print Network [OSTI]

. First, because of the low population densities of French Africa and the high cost of labor rela- tive (2013) tests this hypothesis in the African context showing that lower population density is correlatedExtractive Institutions and Gains From Trade: Evidence from Colonial Africa Federico Tadei A common

Faraon, Andrei

260

PiPe dreams? Jobs Gained, Jobs Lost  

E-Print Network [OSTI]

Petroleum Institute that, if constructed, TransCanada's proposed Keystone XL (KXL) pipeline will generatePiPe dreams? Jobs Gained, Jobs Lost by the ConstruCtion of Keystone XL a rePort by Corne, and Induced) Jobs from Keystone XL 26 KXL Will Have Minor Impact on Unemployment Levels 27 Four Ways Keystone

Danforth, Bryan Nicholas

Note: This page contains sample records for the topic "heat gain coefficient" 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

Radiative Heat Transfer between Neighboring Particles  

E-Print Network [OSTI]

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

Alejandro Manjavacas; F. Javier Garcia de Abajo

2012-01-26T23:59:59.000Z

262

U-178: VMware vMA Library Loading Error Lets Local Users Gain...  

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

Buffer Overflow and Null Pointer Dereference Lets Local Users Gain Elevated Privileges U-094: EMC Documentum Content Server Lets Local Administrative Users Gain Elevated Privileges...

263

E-Print Network 3.0 - adaptive gain integrating Sample Search...  

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

is based on a hybrid combination of gain scheduling, B- spline... combination of gain scheduling, B-spline approximation, variable structure control and integral control... the...

264

Study of natural convection heat transfer above a horizontal heated plate using a laser specklegram technique  

E-Print Network [OSTI]

flow from the horizontal isothermal plate. 15. Study of the effect of aspect ratio (AR) of the heated surface on the global Nusselt number for Ra = 104 50 NOMENCLATURE a distance between the test section and the second parabolic mirror (mm) b... plane of a CCD-camera (mm) h heat transfer coefficient. K Gladstone ? Dale constant for air ( m'/kg) . K, thermal conductivity of air ((tj)/m-'C) L Length of the test section measured along the optical axis m magnification of the second (parabolic...

Cheeti, Satish K.R.

1993-01-01T23:59:59.000Z

265

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

266

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...

Hindawai, S. M.

2010-01-01T23:59:59.000Z

267

Direct fired heat exchanger  

SciTech Connect (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

268

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

269

Numerical Modelling of Combined Heat Transfers in a Double Skin Faade -Full Scale Laboratory  

E-Print Network [OSTI]

, thermal comfort, visual comfort or energy gain [1]. In the current context of global warming, depletion heat transfers are also taken into account to obtain a global coupling between the different phenomena on two levels: during the winter period, the solar energy is used to heat the air in the façade [2], and

270

Self supporting heat transfer element  

DOE Patents [OSTI]

The present invention provides an improved internal heat exchange element arranged so as to traverse the inside diameter of a container vessel such that it makes good mechanical contact with the interior wall of that vessel. The mechanical element is fabricated from a material having a coefficient of thermal conductivity above about 0.8 W cm.sup.-1.degree. K.sup.-1 and is designed to function as a simple spring member when that member has been cooled to reduce its diameter to just below that of a cylindrical container or vessel into which it is placed and then allowed to warm to room temperature. A particularly important application of this invention is directed to a providing a simple compartmented storage container for accommodating a hydrogen absorbing alloy.

Story, Grosvenor Cook (Livermore, CA); Baldonado, Ray Orico (Livermore, CA)

2002-01-01T23:59:59.000Z

271

Geothermal heat pump grouting materials  

SciTech Connect (OSTI)

The thermal conductivity of cementitious grouts has been investigated in order to determine suitability of these materials for grouting vertical boreholes used with geothermal heat pumps. The roles of mix variables such as water/cement ratio, sand/cement ratio and superplasticizer dosage were measured. The cement-sand grouts were also tested for rheological characteristics, bleeding, permeability, bond to HDPE pipe, shrinkage, coefficient of thermal expansion, exotherm, durability and environmental impact. This paper summarizes the thermal conductivity, permeability, bonding and exotherm data for selected cementitious grouts. The theoretical reduction in bore length that could be achieved with the BNL-developed cement-sand grouts is examined. Finally, the FY 98 research and field trials are discussed.

Allan, M.

1998-08-01T23:59:59.000Z

272

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

273

Heat Treating Apparatus  

DOE Patents [OSTI]

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

De Saro, Robert (Annandale, NJ); Bateman, Willis (Sutton Colfield, GB)

2002-09-10T23:59:59.000Z

274

Heat pump/refrigerator using liquid working fluid  

DOE Patents [OSTI]

A heat transfer device is described that can be operated as a heat pump or refrigerator, which utilizes a working fluid that is continuously in a liquid state and which has a high temperature-coefficient of expansion near room temperature, to provide a compact and high efficiency heat transfer device for relatively small temperature differences as are encountered in heating or cooling rooms or the like. The heat transfer device includes a pair of heat exchangers that may be coupled respectively to the outdoor and indoor environments, a regenerator connecting the two heat exchangers, a displacer that can move the liquid working fluid through the heat exchangers via the regenerator, and a means for alternately increasing and decreasing the pressure of the working fluid. The liquid working fluid enables efficient heat transfer in a compact unit, and leads to an explosion-proof smooth and quiet machine characteristic of hydraulics. The device enables efficient heat transfer as the indoor-outdoor temperature difference approaches zero, and enables simple conversion from heat pumping to refrigeration as by merely reversing the direction of a motor that powers the device.

Wheatley, John C. (Del Mar, CA); Paulson, Douglas N. (Del Mar, CA); Allen, Paul C. (Solana Beach, CA); Knight, William R. (Corvallis, OR); Warkentin, Paul A. (San Diego, CA)

1982-01-01T23:59:59.000Z

275

Thermoelectric heat exchange element  

DOE Patents [OSTI]

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

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

2007-08-14T23:59:59.000Z

276

Technical Note Theoretical analysis of film condensation heat transfer  

E-Print Network [OSTI]

transfer coefficient of steam condensing inside an equilateral triangular channel is found. They divided the condensation area on the micro-fin surface into the flooded and the unflooded areasTechnical Note Theoretical analysis of film condensation heat transfer inside vertical mini

Zhao, Tianshou

277

Heat Integrate Heat Engines in Process Plants  

E-Print Network [OSTI]

of forcing a good fit between a heat engine and process T', H profiles extends the ideas of appropriate and inappropriate placement to give bet ter overall integration schemes [7] . The new 'and powerful representations of the thermodynamics of a process... HEAT INTEGRATE HEAT ENGINES IN PROCESS PLANTS E. Hindmarsh, D. Boland and D.W. Townsend TENSA Technology, Houston, Texas Shorter Version Appeared in Chemical Engineering Copyright McGraw Hill, 1985 ABSTRACT This paper presents a novel method...

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

278

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

SciTech Connect (OSTI)

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

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

2013-08-14T23:59:59.000Z

279

Physical model for the latent heat of fusion  

E-Print Network [OSTI]

The atomic movement induced on melting has to overcome a viscous drag resistance. It is suggested that the latent heat of fusion supplies the required energy for this physical process. The viscosity model introduced here allows computation of the latent heat from viscosity, molar volume, melting temperature, and atomic mass and diameter. The correlation between these parameters and the latent heat of 14 elements with body and face centered cubic structures was exceptional, with the correlation coefficients of 0.97 and 0.95 respectively.

Jozsef Garai

2004-11-06T23:59:59.000Z

280

1 Copyright 2012 by ASME Proceedings of the ASME 2012 Summer Heat Transfer Conference  

E-Print Network [OSTI]

1 Copyright © 2012 by ASME Proceedings of the ASME 2012 Summer Heat Transfer Conference HT2012 July. INTRODUCTION Passive cooling is a widely preferred method for electronic and power electronic devices since, #12;2 Copyright © 2012 by ASME is convective heat transfer coefficient and is thermal conductivity

Bahrami, Majid

Note: This page contains sample records for the topic "heat gain coefficient" 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

JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER Vol. 19, No. 1, JanuaryMarch 2005  

E-Print Network [OSTI]

developed turbulent nonrotating tube flow Dh, D = hydraulic diameter, m h = heat transfer coefficient, W/m2 Program, Department of Civil Engineer- ing. Senior Member AIAA. Professor, Turbine Heat Transfer thermal efficiency, gas-turbine stages are being de- signed to operate at increasingly high inlet

Al-Qahtani, Mohammad

282

Absorption, emission, and gain spectra of 1. 3. mu. m InGaAsP quaternary lasers  

SciTech Connect (OSTI)

The spontaneous emission spectrum of mesa lasers was analyzed to determine the absorption and gain spectra at threshold. The radiative current density at threshold was found to be 4.4 kA cm/sup -2/ ..mu..m/sup -1/, which is 60 percent of the total current density for the lowest threshold mesa laser. The increase in radiative lifetime due to reabsorption of emitted radiation was calculated to be 1.5, using the measured absorption and emission spectra. Contrary to other studies, this investigation of an LED and 3 lasers of different types yielded no evidence of carrier heating.

Henry, C.H.; Logan, R.A.; Merritt, F.R.; Temkin, H.

1983-06-01T23:59:59.000Z

283

Radio interferometric gain calibration as a complex optimization problem  

E-Print Network [OSTI]

Recent developments in optimization theory have extended some traditional algorithms for least-squares optimization of real-valued functions (Gauss-Newton, Levenberg-Marquardt, etc.) into the domain of complex functions of a complex variable. This employs a formalism called the Wirtinger derivative, and derives a full-complex Jacobian counterpart to the conventional real Jacobian. We apply these developments to the problem of radio interferometric gain calibration, and show how the general complex Jacobian formalism, when combined with conventional optimization approaches, yields a whole new family of calibration algorithms, including those for the polarized and direction-dependent gain regime. We further extend the Wirtinger calculus to an operator-based matrix calculus for describing the polarized calibration regime. Using approximate matrix inversion results in computationally efficient implementations; we show that some recently proposed calibration algorithms such as StefCal and peeling can be understood...

Smirnov, Oleg

2015-01-01T23:59:59.000Z

284

attenuation coefficient determination: Topics by E-print Network  

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

The emissivity-reduction coefficient ranges from about 0.44 to 1.00 within the umbra and 0.29 to 0.72 in the sunspot, and accounts for only abo... Ilonidis, Stathis;...

285

activity coefficient model: Topics by E-print Network  

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

coefficient and viscosity of popular rigid water models: Two non polarizable ones (SPCE with 3 sites, and TIP4P2005 with 4 sites) and a polarizable one (Dang-Chang, 4...

286

activity coefficient models: Topics by E-print Network  

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

coefficient and viscosity of popular rigid water models: Two non polarizable ones (SPCE with 3 sites, and TIP4P2005 with 4 sites) and a polarizable one (Dang-Chang, 4...

287

Commuting differential operators of rank 2 with polynomial coefficients  

E-Print Network [OSTI]

In this paper we study self-adjoint commuting ordinary differential operators with polynomial coefficients. These operators define commutative subalgebras of the first Weyl algebra. We find new examples of commuting operators of rank 2.

Vardan Oganesyan

2014-09-29T23:59:59.000Z

288

Measurements of molecular and thermal diffusion coefficients in ternary mixtures  

E-Print Network [OSTI]

of a polymer and a colloid in a water-ethanol solvent, treating the ternary mixture as a pseudobinary; Gans et polymer in a water-ethanol solvent mixture. They reported a sign change in the Soret coefficient

Firoozabadi, Abbas

289

On the friction coefficient of straight-chain aggregates  

E-Print Network [OSTI]

A methodology to calculate the friction coefficient of an aggregate in the continuum regime is proposed. The friction coefficient and the monomer shielding factors, aggregate-average or individual, are related to the molecule-aggregate collision rate that is obtained from the molecular diffusion equation with an absorbing boundary condition on the aggregate surface. Calculated friction coefficients of straight chains are in very good agreement with previous results, suggesting that the friction coefficients may be accurately calculated from the product of the collision rate and an average momentum transfer,the latter being independent of aggregate morphology. Langevin-dynamics simulations show that the diffusive motion of straight-chain aggregates may be described either by a monomer-dependent or an aggregate-average random force, if the shielding factors are appropriately chosen.

Lorenzo Isella; Yannis Drossinos

2010-07-16T23:59:59.000Z

290

apparent diffusion coefficient: Topics by E-print Network  

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

4 sites). We exploit the dependence of the diffusion coefficient on the system size Yeh and Hummer, J. Phys. Chem. B 108, 15873 (2004) to obtain the size-independent...

291

apparent diffusion coefficients: Topics by E-print Network  

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

4 sites). We exploit the dependence of the diffusion coefficient on the system size Yeh and Hummer, J. Phys. Chem. B 108, 15873 (2004) to obtain the size-independent...

292

A dynamic model for the Lagrangian stochastic dispersion coefficient  

SciTech Connect (OSTI)

A stochastic sub-grid model is often used to accurately represent particle dispersion in turbulent flows using large eddy simulations. Models of this type have a free parameter, the dispersion coefficient, which is not universal and is strongly grid-dependent. In the present paper, a dynamic model for the evaluation of the coefficient is proposed and validated in decaying homogeneous isotropic turbulence. The grid dependence of the static coefficient is investigated in a turbulent mixing layer and compared to the dynamic model. The dynamic model accurately predicts dispersion statistics and resolves the grid-dependence. Dispersion statistics of the dynamically calculated constant are more accurate than any static coefficient choice for a number of grid spacings. Furthermore, the dynamic model produces less numerical artefacts than a static model and exhibits smaller sensitivity in the results predicted for different particle relaxation times.

Pesmazoglou, I.; Navarro-Martinez, S., E-mail: s.navarro@imperial.ac.uk [Department of Mechanical Engineering, Imperial College, London SW7 2AZ (United Kingdom); Kempf, A. M. [Chair of Fluid Dynamics, Institute for Combustion and Gasdynamics and Center for Computational Sciences and Simulation, Universität Duisburg-Essen, Duisburg, 47048 (Germany)] [Chair of Fluid Dynamics, Institute for Combustion and Gasdynamics and Center for Computational Sciences and Simulation, Universität Duisburg-Essen, Duisburg, 47048 (Germany)

2013-12-15T23:59:59.000Z

293

Use of structure coefficients in published reports of regression analysis  

E-Print Network [OSTI]

for the multiplicative weights can no longer be used alone in formulating interpretations. Although many techniques have been suggested to help in these situations, structure coefficients, or the correlations between predictor variables and the synthetic variable...

Courville, Troy Gerard

1999-01-01T23:59:59.000Z

294

Gaining Top Management Support for Energy Conservation Programs  

E-Print Network [OSTI]

GAINING TOP MANAGEMENT SUPPORT FOR ENERGY CONSERVATION PROGRAMS W. F. Kenney Exxon Chemical Company Florham Park, New Jersey ABSTRACT Sometimes seemingly attractive energy con 1 have attempted to generalize these considerations servation... in your efforts. References [1] W. F. Kenney, IECTC 1983 "Some Observations I on Energy Efficiency and Capital Costs." 17 ESL-IE-84-04-04 Proceedings from the Sixth Annual Industrial Energy Technology Conference Volume I, Houston, TX, April 15...

Kenney, W. F.

1984-01-01T23:59:59.000Z

295

Gain-assisted superluminal light propagation via incoherent pump field  

E-Print Network [OSTI]

We investigate the dispersion and the absorption properties of a weak probe field in a three-level Lambda-type atomic system. We use just an incoherent field for controlling the group velocity of light. It is shown that the slope of dispersion changes from positive to negative just with changing the intensity of the indirect incoherent pumping field. Gain-assisted superluminal light propagation appears in this system. No laser field is used in the pumping processes.

M. Mahmoudi; S. Worya Rabiei; L. Safari; M. Sahrai

2008-08-03T23:59:59.000Z

296

A very high frequency CMOS Variable Gain Amplifier  

E-Print Network [OSTI]

of the VGA output signal . . . . . . . . . 80 Bandwidth with different frequency compensation circuits bias current at 22dB gain setting. . . 84 XIV VGA comparison . . . 88 LIST OF FIGURE FIGURE I 2", 3 and 4'" order sigma-delta modulator SNR vs. input... level . . . . Page 2 Block diagram of a direct conversion receiver. 3 Single transistor transconductor 4 Differential pair 5 Source degeneration amplifier. 6 Four-quadrant multiplier basic architectures . . . . . . . . 10 7 Multiplier as a...

Tan, Siang Tong

2012-06-07T23:59:59.000Z

297

High gain preamplifier based on optical parametric amplification  

DOE Patents [OSTI]

A high-gain preamplifier based on optical parametric amplification. A first nonlinear crystal is operatively connected to a second nonlinear crystal. A first beam relay telescope is operatively connected to a second beam relay telescope, to the first nonlinear crystal, and to the second nonlinear crystal. A first harmonic beamsplitter is operatively connected to a second harmonic beamsplitter, to the first nonlinear crystal, to the second nonlinear crystal, to the first beam relay telescope, and to the second beam relay telescope.

Jovanovic, Igor; Bonner, Randal A.

2004-08-10T23:59:59.000Z

298

Coefficient quantization effects in block state variable digital filters  

E-Print Network [OSTI]

COEFFICIENT QUANTIZATION EFFECTS IN BLOCK STATE VARIABLE DIGITAL FILTERS A Thesis by KAB JOO LEE Submitted to the Office of Graduate Studies of Texas ARM University in partial fulfillment of the requirements for the degree of MASTER... OF SCIENCE August 1991 Major Subject: Electrical Engineering COEFFICIENT QIJANTIZATIOU EFFECTS IN l3LOCI~ STATE VARIABLE DIGITAL FILTERS A Thesis hs IiAB JOO LEE Approved as to style and content by: WVilliam G. )3liss (Chair of Comnaittee) Norman C...

Lee, Kab Joo

2012-06-07T23:59:59.000Z

299

Notes 14. Experimental identification of bearing force coefficients  

E-Print Network [OSTI]

An example of system parameter identification (Hybrid Brush Seal) Luis San Andr?s (lecturer) Thanks to Adolfo Delgado, Jos? Baker (RAs) & support from Siemens Power Generation MEEN 617 - April 2008 Structural parameters K shaft = 243 lbf/in (42...Notes 14. IDENTIFICATION OF BEARING FORCE COEFFICIENTS. ? Dr. Luis San Andr?s (2009) 1 Handout # 14 (MEEN 626) Application example Experimental identification of bearing force coefficients Experimental identification of the dynamic force...

San Andres, Luis

2009-01-01T23:59:59.000Z

300

Coefficient ? as a growth analysis parameter for wheat  

E-Print Network [OSTI]

Subject: Agronony COEFFICIENT u AS A GROWTH ANALYSIS PARAMETER FOR WHEAT A Thesis by JEAN-FRANCOIS LEDENT Approved as to style and content by: c x& W&~ (Chairman of Committee) (Member ) (Head of Department) Member) (Member) /'L~C e (Memb er...) August 1969 ABSTRACT COEFFICIL'NT u AS A GROWTH ANALYSIS PARAMETER FOR WHEAT (August 1969) Jean-Francoi. s Ledent, Ingenieur Agronome, Universite de Louvain (Belgium) Directed by: Dr. E. C. Holt Coefficient u , a growth parameter. , was calculated...

Ledent, Jean-Francois

1969-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heat gain coefficient" 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

Spatially Similar Practice Immediately Following Motor Sequence Learning Eliminates Offline Gains  

E-Print Network [OSTI]

early during motor sequence learning but highlight the sensitivity of offline gains to task practice order....

Handa, Atul

2012-11-30T23:59:59.000Z

302

Enhanced boiling heat transfer in horizontal test bundles  

SciTech Connect (OSTI)

Two-phase flow boiling from bundles of horizontal tubes with smooth and enhanced surfaces has been investigated. Experiments were conducted in pure refrigerant R-113, pure R-11, and mixtures of R-11 and R-113 of approximately 25, 50, and 75% of R-113 by mass. Tests were conducted in two staggered tube bundles consisting of fifteen rows and five columns laid out in equilateral triangular arrays with pitch-to-diameter ratios of 1.17 and 1.5. The enhanced surfaces tested included a knurled surface (Wolverine`s Turbo-B) and a porous surface (Linde`s High Flux). Pool boiling tests were conducted for each surface so that reference values of the heat transfer coefficient could be obtained. Boiling heat transfer experiments in the tube bundles were conducted at pressures of 2 and 6 bar, heat flux values from 5 to 80 kW/m{sup 2}s, and qualities from 0% to 80%, Values of the heat transfer coefficients for the enhanced surfaces were significantly larger than for the smooth tubes and were comparable to the values obtained in pool boiling. It was found that the performance of the enhanced tubes could be predicted using the pool boiling results. The degradation in the smooth tube heat transfer coefficients obtained in fluid mixtures was found to depend on the difference between the molar concentration in the liquid and vapor.

Trewin, R.R.; Jensen, M.K.; Bergles, A.E.

1994-08-01T23:59:59.000Z

303

Heat Transfer Enhancement for Finned-tube Heat Exchangers with Winglets  

SciTech Connect (OSTI)

This paper presents the results of an experimental study of forced convection heat transfer in a narrow rectangular duct fitted with a circular tube and/or a delta-winglet pair. The duct was designed to simulate a single passage in a fin-tube heat exchanger. Heat transfer measurements were obtained using a transient technique in which a heated airflow is suddenly introduced to the test section. High-resolution local fin-surface temperature distributions were obtained at several times after initiation of the transient using an imaging infrared camera. Corresponding local fin-surface heat transfer coefficient distributions were then calculated from a locally applied one-dimensional semi-infinite inverse heat conduction model. Heat transfer results were obtained over an airflow rate ranging from 1.51 x 10-3 to 14.0 x 10-3 kg/s. These flow rates correspond to a duct-height Reynolds number range of 670 – 6300 with a duct height of 1.106 cm and a duct width-toheight ratio, W/H, of 11.25. The test cylinder was sized such that the diameter-to-duct height ratio, D/H is 5. Results presented in this paper reveal visual and quantitative details of local fin-surface heat transfer distributions in the vicinity of a circular tube, a delta-winglet pair, and a combination of a circular tube and a delta-winglet pair. Comparisons of local and average heat transfer distributions for the circular tube with and without winglets are provided. Overall mean finsurface Nusselt-number results indicate a significant level of heat transfer enhancement associated with the deployment of the winglets with the circular cylinder. At the lowest Reynolds numbers (which correspond to the laminar operating conditions of existing geothermal air-cooled condensers), the enhancement level is nearly a factor of two. At higher Reynolds numbers, the enhancement level is close to 50%.

O'Brien, James Edward; Sohal, Manohar Singh

2000-11-01T23:59:59.000Z

304

Heat Transfer Enhancement for Finned-Tube Heat Exchangers with Vortex Generators: Experimental and Numerical Results  

SciTech Connect (OSTI)

A combined experimental and numerical investigation is under way to investigate heat transfer enhancement techniques that may be applicable to large-scale air-cooled condensers such as those used in geothermal power applications. The research is focused on whether air-side heat transfer can be improved through the use of finsurface vortex generators (winglets,) while maintaining low heat exchanger pressure drop. A transient heat transfer visualization and measurement technique has been employed in order to obtain detailed distributions of local heat transfer coefficients on model fin surfaces. Pressure drop measurements have also been acquired in a separate multiple-tube row apparatus. In addition, numerical modeling techniques have been developed to allow prediction of local and average heat transfer for these low-Reynolds-number flows with and without winglets. Representative experimental and numerical results presented in this paper reveal quantitative details of local fin-surface heat transfer in the vicinity of a circular tube with a single delta winglet pair downstream of the cylinder. The winglets were triangular (delta) with a 1:2 height/length aspect ratio and a height equal to 90% of the channel height. Overall mean fin-surface Nusselt-number results indicate a significant level of heat transfer enhancement (average enhancement ratio 35%) associated with the deployment of the winglets with oval tubes. Pressure drop measurements have also been obtained for a variety of tube and winglet configurations using a single-channel flow apparatus that includes four tube rows in a staggered array. Comparisons of heat transfer and pressure drop results for the elliptical tube versus a circular tube with and without winglets are provided. Heat transfer and pressure-drop results have been obtained for flow Reynolds numbers based on channel height and mean flow velocity ranging from 700 to 6500.

O'Brien, James Edward; Sohal, Manohar Singh; Huff, George Albert

2002-08-01T23:59:59.000Z

305

Profiles of heating in turbulent coronal magnetic loops  

E-Print Network [OSTI]

Context: The location of coronal heating in magnetic loops has been the subject of a long-lasting controversy: does it occur mostly at the loop footpoints, at the top, is it random, or is the average profile uniform? Aims: We try to address this question in model loops with MHD turbulence and a profile of density and/or magnetic field along the loop. Methods: We use the ShellAtm MHD turbulent heating model described in Buchlin & Velli (2006), with a static mass density stratification obtained by the HydRad model (Bradshaw & Mason 2003). This assumes the absence of any flow or heat conduction subsequent to the dynamic heating. Results: The average profile of heating is quasi-uniform, unless there is an expansion of the flux tube (non-uniform axial magnetic field) or the variation of the kinetic and magnetic diffusion coefficients with temperature is taken into account: in the first case the heating is enhanced at footpoints, whereas in the second case it is enhanced where the dominant diffusion coefficient is enhanced. Conclusions: These simulations shed light on the consequences on heating profiles of the complex interactions between physical effects involved in a non-uniform turbulent coronal loop.

E. Buchlin; P. J. Cargill; S. J. Bradshaw; M. Velli

2007-02-28T23:59:59.000Z

306

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

307

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

308

Central solar heating plants with seasonal storage in mines  

SciTech Connect (OSTI)

The solar assisted heat supply of building offers a great technical potential for the substitution of fossil energy sources. Central solar Heating Plants with Seasonal Storage (CSHPSS) supply 100 and more buildings and reach a solar fraction of 50% or more of the total load with far less specific heat costs [$/kWh{sub solar}] compared to small domestic hot water systems (DHW) for single-family houses. However, the construction of seasonal storage is too expensive. At the Ruhu University Bochum the use of mines for a seasonal storage of low temperature heat is examined in cooperation with industrial partners. The use of available storage volumes may lead to a decrease of investment costs. Additional geothermal heat gains can be obtained from the warm surrounding rock; therefore a high efficiency can be achieved.

Eikmeier, B.; Mohr, M.; Unger, H.

1999-07-01T23:59:59.000Z

309

About influence of gravity on heat conductivity process of the Planets  

E-Print Network [OSTI]

In the present study it is shown that the interaction of a quasi-static gravitational wave through density fluctuations gives rise to a heat conductivity coefficient and hence temperature. This fact is a very important characteristics to establish a heat equilibrium process of such massive body as the Earth and other Planets. To carry out this exercise general mechanism has been provided, which makes a bridge between classical physics and quantum theory, and specific dependence of heat conductivity coefficient in wide region is also calculated.

S. O. Gladkov; Anil Yadav; Saibal Ray; F. Rahaman

2014-07-30T23:59:59.000Z

310

About influence of gravity on heat conductivity process of the Planets  

E-Print Network [OSTI]

In the present study it is shown that the interaction of a quasi-static gravitational wave through density fluctuations gives rise to a heat conductivity coefficient and hence temperature. This fact is a very important characteristics to establish a heat equilibrium process of such massive body as the Earth and other Planets. To carry out this exercise general mechanism has been provided, which makes a bridge between classical physics and quantum theory, and specific dependence of heat conductivity coefficient in wide region is also calculated.

Gladkov, S O; Ray, Saibal; Rahaman, F

2015-01-01T23:59:59.000Z

311

Consolidated Electric Cooperative- Heat Pump and Water Heating Rebates  

Broader source: Energy.gov [DOE]

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

312

Microchannel crossflow fluid heat exchanger and method for its fabrication  

DOE Patents [OSTI]

A microchannel crossflow fluid heat exchanger and a method for its fabrication are disclosed. The heat exchanger is formed from a stack of thin metal sheets which are bonded together. The stack consists of alternating slotted and unslotted sheets. Each of the slotted sheets includes multiple parallel slots which form fluid flow channels when sandwiched between the unslotted sheets. Successive slotted sheets in the stack are rotated ninety degrees with respect to one another so as to form two sets of orthogonally extending fluid flow channels which are arranged in a crossflow configuration. The heat exchanger has a high surface to volume ratio, a small dead volume, a high heat transfer coefficient, and is suitable for use with fluids under high pressures. The heat exchanger has particular application in a Stirling engine that utilizes a liquid as the working substance.

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

1985-01-01T23:59:59.000Z

313

Microchannel crossflow fluid heat exchanger and method for its fabrication  

DOE Patents [OSTI]

A microchannel crossflow fluid heat exchanger and a method for its fabrication are disclosed. The heat exchanger is formed from a stack of thin metal sheets which are bonded together. The stack consists of alternating slotted and unslotted sheets. Each of the slotted sheets includes multiple parallel slots which form fluid flow channels when sandwiched between the unslotted sheets. Successive slotted sheets in the stack are rotated ninety degrees with respect to one another so as to form two sets of orthogonally extending fluid flow channels which are arranged in a crossflow configuration. The heat exchanger has a high surface to volume ratio, a small dead volume, a high heat transfer coefficient, and is suitable for use with fluids under high pressures. The heat exchanger has particular application in a Stirling engine that utilizes a liquid as the working substance. 9 figs.

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

1985-05-14T23:59:59.000Z

314

Microchannel crossflow fluid heat exchanger and method for its fabrication  

DOE Patents [OSTI]

A microchannel crossflow fluid heat exchanger and a method for its fabrication are disclosed. The heat exchanger is formed from a stack of thin metal sheets which are bonded together. The stack consists of alternating slotted and unslotted sheets. Each of the slotted sheets includes multiple parallel slots which form fluid flow channels when sandwiched between the unslotted sheets. Successive slotted sheets in the stack are rotated ninety degrees with respect to one another so as to form two sets of orthogonally extending fluid flow channels which are arranged in a crossflow configuration. The heat exchanger has a high surface to volume ratio, a small dead volume, a high heat transfer coefficient, and is suitable for use with fluids under high pressures. The heat exchanger has particular application in a Stirling engine that utilizes a liquid as the working substance.

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

1982-08-31T23:59:59.000Z

315

Photovoltaic roof heat flux  

E-Print Network [OSTI]

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

Samady, Mezhgan Frishta

2011-01-01T23:59:59.000Z

316

HEAT TRANSFER FLUIDS  

E-Print Network [OSTI]

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

Lenert, Andrej

2012-01-01T23:59:59.000Z

317

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

318

MA HEAT Loan Overview  

Broader source: Energy.gov [DOE]

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

319

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

320

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

Note: This page contains sample records for the topic "heat gain coefficient" 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

Development of a Transient Heat and Mass Transfer Model of Residential Attics to Predict Energy Savings Produced by the Use of Radiant Barriers  

E-Print Network [OSTI]

A transient heat and mass transfer model was developed to predict ceiling heat gain/loss through the attic space in residences and to accurately estimate savings in cooling and heating loads produced by the use of radiant barriers. The model...

Medina, M. A.

322

Ammoniated salt heat pump  

SciTech Connect (OSTI)

A thermochemical heat pump/energy storage system using liquid ammoniate salts is described. The system, which can be used for space heating or cooling, provides energy storage for both functions. The bulk of the energy is stored as chemical energy and thus can be stored indefinitely. The system is well suited to use with a solar energy source or industrial waste heat.

Haas, W.R.; Jaeger, F.J.; Giordano, T.J.

1981-01-01T23:59:59.000Z

323

Heat Transfer Guest Editorial  

E-Print Network [OSTI]

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

Kandlikar, Satish

324

Acoustic Heating Peter Ulmschneider  

E-Print Network [OSTI]

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

Ulmschneider, Peter

325

Pioneering Heat Pump Project  

Broader source: Energy.gov [DOE]

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

326

LIMB-DARKENING COEFFICIENTS FOR ECLIPSING WHITE DWARFS  

SciTech Connect (OSTI)

We present extensive calculations of linear and nonlinear limb-darkening coefficients as well as complete intensity profiles appropriate for modeling the light-curves of eclipsing white dwarfs. We compute limb-darkening coefficients in the Johnson-Kron-Cousins UBVRI photometric system as well as the Large Synoptic Survey Telescope (LSST) ugrizy system using the most up to date model atmospheres available. In all, we provide the coefficients for seven different limb-darkening laws. We describe the variations of these coefficients as a function of the atmospheric parameters, including the effects of convection at low effective temperatures. Finally, we discuss the importance of having readily available limb-darkening coefficients in the context of present and future photometric surveys like the LSST, Palomar Transient Factory, and the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS). The LSST, for example, may find {approx}10{sup 5} eclipsing white dwarfs. The limb-darkening calculations presented here will be an essential part of the detailed analysis of all of these systems.

Gianninas, A.; Strickland, B. D.; Kilic, Mukremin [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks St., Norman, OK 73019 (United States)] [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks St., Norman, OK 73019 (United States); Bergeron, P., E-mail: alexg@nhn.ou.edu, E-mail: benstrickland@ou.edu, E-mail: kilic@ou.edu, E-mail: bergeron@astro.umontreal.ca [Departement de Physique, Universite de Montreal, C.P. 6128, Succ. Centre-Ville, Montreal, Quebec H3C 3J7 (Canada)

2013-03-20T23:59:59.000Z

327

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

328

Enhanced convective and film boiling heat transfer by surface gas injection  

SciTech Connect (OSTI)

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

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

1992-04-01T23:59:59.000Z

329

Enhanced convective and film boiling heat transfer by surface gas injection  

SciTech Connect (OSTI)

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

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

1992-04-01T23:59:59.000Z

330

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

331

Experimental investigations of uncovered-bundle heat transfer and two-phase mixture-level swell under high-pressure low heat-flux conditions. [PWR  

SciTech Connect (OSTI)

Results are reported from a series of uncovered-bundle heat transfer and mixture-level swell tests. Experimental testing was performed at Oak Ridge National Laboratory in the Thermal Hydraulic Test Facility (THTF). The THTF is an electrically heated bundle test loop configured to produce conditions similar to those in a small-break loss-of-coolant accident. The objective of heat transfer testing was to acquire heat transfer coefficients and fluid conditions in a partially uncovered bundle. Testing was performed in a quasi-steady-state mode with the heated core 30 to 40% uncovered. Linear heat rates varied from 0.32 to 2.22 kW/m.rod (0.1 to 0.68 kW/ft.rod). Under these conditions peak clad temperatures in excess of 1050 K (1430/sup 0/F) were observed, and total heat transfer coefficients ranged from 0.0045 to 0.037 W/cm/sup 2/.K (8 to 65 Btu/h.ft/sup 2/./sup 0/F). Spacer grids were observed to enhance heat transfer at, and downstream of, the grid. Radiation heat transfer was calculated to account for as much as 65% of total heat transfer in low-flow tests.

Anklam, T. M.; Miller, R. J.; White, M. D.

1982-03-01T23:59:59.000Z

332

Exergy Analysis and Operational Efficiency of a Horizontal Ground Source Heat Pump System Operated in a Low-Energy Test House under Simulated Occupancy Conditions  

SciTech Connect (OSTI)

This paper presents data, analyses, measures of performance, and conclusions for a ground-source heat pump (GSHP) providing space conditioning to a 345m2 house whose envelope is made of structural insulated panels (SIP). The entire thermal load of this SIP house with RSI-3.7 (RUS-21) walls, triple pane windows with a U-factor of 1.64 W/m2 K (0.29 Btu/h ft2 oF) and solar heat gain coefficient (SHGC) of 0.25, a roof assembly with overall thermal resistance of about RSI-8.8 (RUS-50) and low leakage rates of 0.74 ACH at 50Pa was satisfied with a 2.16-Ton (7.56 kW) GSHP unit consuming negligible (9.83kWh) auxiliary heat during peak winter season. The highest and lowest heating COP achieved was 4.90 (October) and 3.44 (February), respectively. The highest and lowest cooling COP achieved was 6.09 (April) and 3.88 (August). These COPs are calculated on the basis of the total power input (including duct, ground loop, and control power losses ). The second Law (Exergy) analysis provides deep insight into how systemic inefficiencies are distributed among the various GSHP components. Opportunities for design and further performance improvements are identified. Through Exergy analysis we provide a true measure of how closely actual performance approaches the ideal, and it unequivocally identifies, better than energy analysis does, the sources and causes of lost work, the root cause of system inefficiencies.

Ally, Moonis Raza [ORNL; Baxter, Van D [ORNL; Munk, Jeffrey D [ORNL; Gehl, Anthony C [ORNL

2012-01-01T23:59:59.000Z

333

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

334

Heart Rate Variability Analysis Using Threshold of Wavelet Package Coefficients  

E-Print Network [OSTI]

In this paper, a new efficient feature extraction method based on the adaptive threshold of wavelet package coefficients is presented. This paper especially deals with the assessment of autonomic nervous system using the background variation of the signal Heart Rate Variability HRV extracted from the wavelet package coefficients. The application of a wavelet package transform allows us to obtain a time-frequency representation of the signal, which provides better insight in the frequency distribution of the signal with time. A 6 level decomposition of HRV was achieved with db4 as mother wavelet, and the above two bands LF and HF were combined in 12 specialized frequencies sub-bands obtained in wavelet package transform. Features extracted from these coefficients can efficiently represent the characteristics of the original signal. ANOVA statistical test is used for the evaluation of proposed algorithm.

Kheder, G; Massoued, M Ben; Samet, M

2009-01-01T23:59:59.000Z

335

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

336

Heat Transfer -2 A pure platinum wire with diameter D = 3 mm and length L = 20 mm is placed outside on a day when air temperature  

E-Print Network [OSTI]

Heat Transfer - 2 A pure platinum wire with diameter D = 3 mm and length L = 20 mm is placed outside on a day when air temperature T = 10o C. The heat transfer coefficient at the wire's surface h equation that includes all heat transfer mechanisms involved in this problem. Write this energy balance

Virginia Tech

337

Thermoelectric energy conversion The objective of this laboratory is for you to explore the physics and practical aspects of solidsate heat  

E-Print Network [OSTI]

exchanger · Two dc power supplies; power supply for running the cooling fan · Thermocouples, heaters, load: Peltier current and solidstate heat pumps · Explore heat Peltier cooling and heating by applying current for this module from the maximum cooling. · Measure the Peltier coefficient of the module by balancing

Braun, Paul

338

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

2001-01-01T23:59:59.000Z

339

RECOMBINATION RATE COEFFICIENTS OF Be-LIKE Si  

SciTech Connect (OSTI)

Recombination of Be-like Si{sup 10+} over the 0-43 eV electron-ion energy range is measured at the CRYRING electron cooler. In addition to radiative and dielectronic recombination, the recombination spectrum also shows strong contributions from trielectronic recombination. Below 100 meV, several very strong resonances associated with a spin-flip of the excited electron dominate the spectrum and also dominate the recombination in the photoionized plasma. The resonant plasma rate coefficients corrected for the experimental field ionization are in good agreement with calculated results by Gu and with AUTOSTRUCTURE calculations. All other calculations significantly underestimate the plasma rate coefficients at low temperatures.

Orban, I.; Boehm, S.; Schuch, R. [Department of Physics, Stockholm University, 10691 Stockholm (Sweden); Loch, S. D. [Department of Physics, Auburn University, Auburn, AL 36849 (United States)

2010-10-01T23:59:59.000Z

340

CIP methods for hyperbolic system with variable and discontinuous coefficient  

E-Print Network [OSTI]

We propose a multi-moment method for one-dimensional hyperbolic equations with smooth coefficient and piecewise constant coefficient. The method is entirely based on the backward characteristic method and uses the solution and its derivative as unknowns and cubic Hermite interpolation for each computational cell. The exact update formula for solution and its derivative is derived and used for an efficient time integration. At points of discontinuity of wave speed we define a piecewise cubic Hermite interpolation based on immersed interface method. The method is extended to the one-dimensional Maxwell's equations with variable material properties.

Ito, Kazufumi

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heat gain coefficient" 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

Connection coefficients for basic Harish-Chandra series  

E-Print Network [OSTI]

Basic Harish-Chandra series are asymptotically free meromorphic solutions of the system of basic hypergeometric difference equations associated to root systems. The associated connection coefficients are explicitly computed in terms of Jacobi theta functions. We interpret the connection coefficients as the transition functions for asymptotically free meromorphic solutions of Cherednik's root system analogs of the quantum Knizhnik-Zamolodchikov equations. They thus give rise to explicit elliptic solutions of root system analogs of dynamical Yang-Baxter and reflection equations. Applications to quantum c-functions, basic hypergeometric functions, reflectionless difference operators and multivariable Baker-Akhiezer functions are discussed.

Jasper V. Stokman

2014-02-10T23:59:59.000Z

342

Lattice-structures and constructs with designed thermal expansion coefficients  

SciTech Connect (OSTI)

A thermal expansion-managed lattice structure having a plurality of unit cells each having flexure bearing-mounted tabs supported on a base and actuated by thermal expansion of an actuator having a thermal expansion coefficient greater than the base and arranged so that the tab is inwardly displaced into a base cavity. The flexure bearing-mounted tabs are connected to other flexure-bearing-mounted tabs of adjacent unit cells so that the adjacent unit cells are spaced from each other to accommodate thermal expansion of individual unit cells while maintaining a desired bulk thermal expansion coefficient of the lattice structure as a whole.

Spadaccini, Christopher; Hopkins, Jonathan

2014-10-28T23:59:59.000Z

343

PERFORMANCE OF A STIRLING ENGINE POWERED HEAT ACTIVATED HEAT PUMP  

E-Print Network [OSTI]

PERFORMANCE OF A STIRLING ENGINE POWERED HEAT ACTIVATED HEAT PUMP W. D. C. Richards and W. L. Auxer General Electric Company Space Division King of Prussia, Pa. ABSTRACT A heat activated heat pump (HAHP for space heating since it directly utilizes the engine waste heat in addition to the energy obtained

Oak Ridge National Laboratory

344

Summer HeatSummer Heat Heat stress solutions  

E-Print Network [OSTI]

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

Liskiewicz, Maciej

345

Heat pump system  

DOE Patents [OSTI]

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

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

1983-01-01T23:59:59.000Z

346

Heat pump system  

DOE Patents [OSTI]

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

Swenson, Paul F.; Moore, Paul B.

1983-06-21T23:59:59.000Z

347

Electrical and Optical Gain Lever Effects in InGaAs Double Quantum Well Diode Lasers  

SciTech Connect (OSTI)

In multisection laser diodes, the amplitude or frequency modulation (AM or FM) efficiency can be improved using the gain lever effect. To study gain lever, InGaAs double quantum well (DQW) edge emitting lasers have been fabricated with integrated passive waveguides and dual sections providing a range of split ratios from 1:1 to 9:1. Both the electrical and the optical gain lever have been examined. An electrical gain lever with greater than 7 dB enhancement of AM efficiency was achieved within the range of appropriate DC biasing currents, but this gain dropped rapidly outside this range. We observed a 4 dB gain in the optical AM efficiency under non-ideal biasing conditions. This value agreed with the measured gain for the electrical AM efficiency under similar conditions. We also examined the gain lever effect under large signal modulation for digital logic switching applications. To get a useful gain lever for optical gain quenched logic, a long control section is needed to preserve the gain lever strength and a long interaction length between the input optical signal and the lasing field of the diode must be provided. The gain lever parameter space has been fully characterized and validated against numerical simulations of a semi-3D hybrid beam propagation method (BPM) model for the coupled electron-photon rate equation. We find that the optical gain lever can be treated using the electrical injection model, once the absorption in the sample is known.

Pocha, M D; Goddard, L L; Bond, T C; Nikolic, R J; Vernon, S P; Kallman, J S; Behymer, E M

2007-01-03T23:59:59.000Z

348

Policies supporting Heat Pump Technologies  

E-Print Network [OSTI]

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

Oak Ridge National Laboratory

349

Adaptive Calculation of Variable Coefficients Elliptic Differential Equations via Wavelets  

E-Print Network [OSTI]

Description Generating a "good" discrete representation for continuous operators is one of the basic problemsAdaptive Calculation of Variable Coefficients Elliptic Differential Equations via Wavelets Amir rather than in the original physical space can speed up the performance of the sparse solver by a factor

Averbuch, Amir

350

On signal reconstruction from absolute value of frame coefficients  

E-Print Network [OSTI]

Edidinb a Siemens Corporate Research, 755 College Road East, Princeton, NJ 08540; b Department transformation from the initial Hilbert space to the space of coefficients obtained by taking the inner product frames, Further author information: Send correspondence to Radu Balan Radu Balan: E-mail: radu.balan@siemens

Casazza, Pete

351

The effective magnetoelectric coefficients of polycrystalline multiferroic composites  

E-Print Network [OSTI]

, emphasizing the effects of shape, volume fraction, and orien- tation distribution of particles of both phases and coupling factors, while randomly oriented particles lead to essentially zero ME coupling, even though that the large discrepancy between theoretical calculations and experimental measurements for ME coefficients

Li, Jiangyu

352

Does the photon-diffusion coefficient depend on absorption?  

E-Print Network [OSTI]

Does the photon-diffusion coefficient depend on absorption? T. Durduran and A. G. Yodh Department independent of absorption, i.e., D0 v/3 s . After presentation of the general theoretical arguments underlying this assertion, Monte Carlo simulations are performed and explicitly reveal that the absorption- independent

Boas, David

353

Electromagnetic fields and transport coefficients in a hot pion gas  

E-Print Network [OSTI]

We present recent results on finite temperature electromagnetic form factors and the electrical conductivity in a pion gas. The standard Chiral Perturbation Theory power counting needs to be modified for transport coefficients. We pay special attention to unitarity and to possible applications for dilepton and photon production.

A. Gomez Nicola; D. Fernandez-Fraile

2006-08-24T23:59:59.000Z

354

Indoor Dose Conversion Coefficients for Radon Progeny for Different  

E-Print Network [OSTI]

Indoor Dose Conversion Coefficients for Radon Progeny for Different Ambient Environments K . N . Y Inhaled progeny of 222Rn (radon progeny) are the most important source of irradiation of the human-, urban-, and marine-influenced aerosols. The ASDs of attached radon progeny for all three studied ambient

Yu, K.N.

355

IDENTIFICATION OF UNDERWATER VEHICLE HYDRODYNAMIC COEFFICIENTS USING FREE  

E-Print Network [OSTI]

been an ever increasing num- ber of applications for unmanned underwater vehicles (UUV) in variousIDENTIFICATION OF UNDERWATER VEHICLE HYDRODYNAMIC COEFFICIENTS USING FREE DECAY TESTS Andrew Ross the potential accuracy of these new methods. Copyright c 2004 IFAC. Keywords: Low-speed underwater vehicles

Johansen, Tor Arne

356

Lifshitz tails for the Interband Light Absorption Coefficient  

E-Print Network [OSTI]

In this paper we consider the Interband Light Absorption Coefficient for various models. We show that at the lower and upper edges of the spectrum the Lifshitz tails behaviour of the density of states implies similar behaviour for the ILAC at appropriate energies. The Lifshitz tails property is also exhibited at some points corresponding to the internal band edges of the density of states.

W. Kirsch; M. Krishna

2009-03-31T23:59:59.000Z

357

E-Print Network 3.0 - activity coefficient Sample Search Results  

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

USING INTERSCALE PHASE RELATIONSHIPS OF COMPLEX WAVELET COEFFICIENTS... Wavelet Transform (DT- CWT) but a phase rotation is applied to the coefficients to create complex...

358

Progress on achieving the ICF conditions needed for high gain  

SciTech Connect (OSTI)

Progress during the past two years has moved us much closer to demonstrating the scientific and technological requirements for high gain ICF in the laboratory. This progress has been made possible by operating at the third harmonic of 1..mu..m light which dramatically reduces concern about hot electrons and by advances in diagnostics such as 100 ps x-ray framing cameras which greatly increase the data available from each experiment. Making use of many of these new capabilities, major improvements in confinement conditions have been achieved for ICF implosions. In particular, in an optimized hohlraum on Nova, radiation driven implosions with convergence ratio in excess of 30 (volume compression /approximately/3 /times/ 10/sup 4/) have performed essentially as predicted by spherical implosion calculations. This paper presents these results as well as examples of advances in several other areas and discusses the implications for the future of ICF with lasers and heavy ion beam drivers. 8 refs., 10 figs.

Lindl, J.D.

1988-12-23T23:59:59.000Z

359

Relative Gain Monitoring of the GlueX Calorimeters  

SciTech Connect (OSTI)

The relative gain of the photodetectors for the GlueX Barrel and Forward calorimeters will be monitored using modular LED driver systems. The BCAL system consists of a global controller that feeds power, bias voltage and trigger signals to 96 local controllers situated at the ends of the 48 BCAL modules, which drive 40 LEDs associated with the 40 light guides at the end of each module. The FCAL system consists also of a global controller, a local controller for each acrylic quadrant covering the face of the FCAL, and ten 4-LED pulser boards per local controller connected in a star configuration along the edges of the acrylic panes. The respective systems are currently being installed on the detectors and their tested performance is presented herein.

Anassontzis, Efstratios G. [JLAB/National and Kapodestrian University of Athens (Greece); Ioannou, P. [National and Kapodestrian University of Athens (Greece); Kourkoumelis, C. [National and Kapodestrian University of Athens (Greece); Vasileiadis, G. [National and Kapodestrian University of Athens (Greece); Voulgaris, G. [National and Kapodestrian University of Athens (Greece); Kappos, E. [Symmetron Electronic Applications, Gerakas (Greece); Beattie, T. [University of Regina, Saskatchewan (Canada); Krueger, S. [University of Regina, Saskatchewan (Canada); Lolos, G. J. [University of Regina, Saskatchewan (Canada); Papandreou, Z. [University of Regina, Saskatchewan (Canada); Semenov, A. Yu. [University of Regina, Saskatchewan (Canada); Frye, John M. [Indiana Univ., Bloomington, IN (United States); Leckey, John P. [Indiana Univ., Bloomington, IN (United States); Shepherd, Matt [Indiana Univ., Bloomington, IN (United States); Bogart, T. [JLAB/CNU, Newport News, VA (United States); Lawrence, David W. [JLAB, Newport News, VA (United States); Smith, Elton S. [JLAB, Newport News, VA (United States)

2014-02-01T23:59:59.000Z

360

Local Heat Transfer for Finned-Tube Heat Exchangers using Oval Tubes  

SciTech Connect (OSTI)

This paper presents the results of an experimental study of forced convection heat transfer in a narrow rectangular duct fitted with either a circular tube or an elliptical tube in crossflow. The duct was designed to simulate a single passage in a fin-tube heat exchanger. Heat transfer measurements were obtained using a transient technique in which a heated airflow is suddenly introduced to the test section. High-resolution local fin-surface temperature distributions were obtained at several times after initiation of the transient using an imaging infrared camera. Corresponding local fin-surface heat transfer coefficient distributions were then calculated from a locally applied one-dimensional semi-infinite inverse heat conduction model. Heat transfer results were obtained over an airflow rate ranging from 1.56 x 10-3 to 15.6 x 10-3 kg/s. These flow rates correspond to a duct-height Reynolds number range of 630 – 6300 with a duct height of 1.106 cm and a duct width-toheight ratio, W/H, of 11.25. The test cylinder was sized such that the diameter-to-duct height ratio, D/H is 5. The elliptical tube had an aspect ratio of 3:1 and a/H equal to 4.33. Results presented in this paper reveal visual and quantitative details of local fin-surface heat transfer distributions in the vicinity of circular and oval tubes and their relationship to the complex horseshoe vortex system that forms in the flow stagnation region. Fin surface stagnation-region Nusselt numbers are shown to be proportional to the square-root of Reynolds number.

O'Brien, James Edward; Sohal, Manohar Singh

2000-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "heat gain coefficient" 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

Fluidized bed heat treating system  

DOE Patents [OSTI]

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

Ripley, Edward B; Pfennigwerth, Glenn L

2014-05-06T23:59:59.000Z

362

E-Print Network 3.0 - annual weight gain Sample Search Results  

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

3 4 5 6 7 8 0 0.5 1 1.5 2 x 10 -3 Lag (trials) RegressionWeight... on effective Gain Landscape The optimal strategy, maximizing expected gain, requires the subject to shift... of...

363

T-671: Red Hat system-config-firewall Lets Local Users Gain Root...  

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

1: Red Hat system-config-firewall Lets Local Users Gain Root Privileges T-671: Red Hat system-config-firewall Lets Local Users Gain Root Privileges July 19, 2011 - 2:42pm Addthis...

364

40 ELR 11106 ENVIRONMENTAL LAW REPORTER 11-2010 Gaining Ground: Wetlands,  

E-Print Network [OSTI]

40 ELR 11106 ENVIRONMENTAL LAW REPORTER 11-2010 Gaining Ground: Wetlands, Hurricanes .5% dis- count rate). Marine waters, wetlands, swamps, agricultural lands, and forests provide natural goods and services . The 1 . David Batker et al ., Gaining Ground: Wetlands, Hurricanes

Vermont, University of

365

Water-heating dehumidifier  

DOE Patents [OSTI]

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

Tomlinson, John J. (Knoxville, TN)

2006-04-18T23:59:59.000Z

366

Rod Bundle Heat Transfer: Steady-State Steam Cooling Experiments  

SciTech Connect (OSTI)

Through the joint efforts of the Pennsylvania State University and the United States Nuclear Regulatory Commission, an experimental rod bundle heat transfer (RBHT) facility was designed and built. The rod bundle consists of a 7 x 7 square pitch array with spacer grids and geometry similar to that found in a modern pressurized water reactor. From this facility, a series of steady-state steam cooling experiments were performed. The bundle inlet Reynolds number was varied from 1 400 to 30 000 over a pressure range from 1.36 to 4 bars (20 to 60 psia). The bundle inlet steam temperature was controlled to be at saturation for the specified pressure and the fluid exit temperature exceeded 550 deg. C in the highest power tests. One important quantity of interest is the local convective heat transfer coefficient defined in terms of the local bulk mean temperature of the flow, local wall temperature, and heat flux. Steam temperatures were measured at the center of selected subchannels along the length of the bundle by traversing miniaturized thermocouples. Using an analogy between momentum and energy transport, a method was developed for relating the local subchannel centerline temperature measurement to the local bulk mean temperature. Wall temperatures were measured using internal thermocouples strategically placed along the length of each rod and the local wall heat flux was obtained from an inverse conduction program. The local heat transfer coefficient was calculated from the data at each rod thermocouple location. The local heat transfer coefficients calculated for locations where the flow was fully developed were compared against several published correlations. The Weisman and El-Genk correlations were found to agree best with the RBHT steam cooling data, especially over the range of turbulent Reynolds numbers. The effect of spacer grids on the heat transfer enhancement was also determined from instrumentation placed downstream of the spacer grid locations. The local heat transfer was found to be greatest at locations immediately downstream of the grid, and as the flow moved further downstream from the grid it became more developed, thus causing the heat transfer to diminish. The amount of heat transfer enhancement was found to depend not only on the spacer grid design, but also on the local Reynolds number. It was seen that decreasing Reynolds number leads to greater heat transfer enhancement. (authors)

Spring, J.P.; McLaughlin, D.M. [The Pennsylvania State University, 201 Shields Building University Park, PA 16802 (United States)

2006-07-01T23:59:59.000Z

367

Effect of microwave reflection from the region of electron cyclotron resonance heating in the L-2M stellarator  

SciTech Connect (OSTI)

In experiments on electron cyclotron resonance (ECR) heating of plasma at the second harmonic of the electron gyrofrequency in the L-2M stellarator, the effect of partial reflection of high-power gyrotron radiation from the ECR heating region located in the center of the plasma column was revealed. The reflection coefficient is found to be on the order of 10{sup ?3}. The coefficient of reflection of an extraordinary wave from the second-harmonic ECR region is calculated in the one-dimensional full-wave model. The calculated and measured values of the reflection coefficient are found to coincide in order of magnitude.

Batanov, G. M.; Borzosekov, V. D.; Kolik, L. V.; Konchekov, E. M.; Malakhov, D. V.; Petrov, A. E.; Sarksyan, K. A.; Sakharov, A. S., E-mail: sakh@fpl.gpi.ru; Skvortsova, N. N.; Stepakhin, V. D.; Kharchev, N. K. [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation)] [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation)

2013-11-15T23:59:59.000Z

368

Heat storage duration  

SciTech Connect (OSTI)

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

Balcomb, J.D.

1981-01-01T23:59:59.000Z

369

Investigation of spectrally broad gain multiple-width quantum well material for colliding pulse  

E-Print Network [OSTI]

and MWQW devices, are shown in Fig. 1. At zero net modal gain, confined material gain is equal just below 1:5 kA cm�2 ; the net modal gain contribution is zero at 1560 nm, corresponding contributed to the zero net modal gain before the narrow wells at a current density of 2­3 kA cm�2 : The 6

370

Room temperature broadband terahertz gains in graphene heterostructures based on inter-layer radiative transitions  

SciTech Connect (OSTI)

We exploit inter-layer radiative transitions to provide gains to amplify terahertz waves in graphene heterostructures. This is achieved by properly doping graphene sheets and aligning their energy bands so that the processes of stimulated emissions can overwhelm absorptions. We derive an expression for the gain estimation and show the gain is insensitive to temperature variation. Moreover, the gain is broadband and can be strong enough to compensate the free carrier loss, indicating graphene based room temperature terahertz lasers are feasible.

Tang, Linlong [Key Laboratory of High Energy Density Physics and Technology, College of Physics and Technology, Sichuan University, Chengdu, 610064 (China); Chongqing institute of green and intelligent technology, Chinese Academy of Sciences, Chongqing, 401122 (China); Du, Jinglei, E-mail: dujl@scu.edu.cn [Key Laboratory of High Energy Density Physics and Technology, College of Physics and Technology, Sichuan University, Chengdu, 610064 (China); Shi, Haofei, E-mail: shi@cigit.ac.cn; Wei, Dongshan; Du, Chunlei, E-mail: cldu@cigit.ac.cn [Chongqing institute of green and intelligent technology, Chinese Academy of Sciences, Chongqing, 401122 (China)

2014-10-15T23:59:59.000Z

371

Solar Heating in Uppsala.  

E-Print Network [OSTI]

?? The housing corporation Uppsalahem has installed asolar heating system in the neighbourhood Haubitsen,which was renovated in 2011. This report examineshow much energy the solar… (more)

Blomqvist, Emelie; Häger, Klara

2012-01-01T23:59:59.000Z

372

Solar heating in Colombia.  

E-Print Network [OSTI]

?? This report describes the process of a thesis implemented in Colombia concerning solar energy. The project was to install a self-circulating solar heating system,… (more)

Skytt, Johanna

2012-01-01T23:59:59.000Z

373

Waste Heat Recovery  

Office of Environmental Management (EM)

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

374

Heat and mass exchanger  

DOE Patents [OSTI]

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

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

2007-09-18T23:59:59.000Z

375

Heat and mass exchanger  

DOE Patents [OSTI]

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

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

2011-06-28T23:59:59.000Z

376

HEATS: Thermal Energy Storage  

SciTech Connect (OSTI)

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

None

2012-01-01T23:59:59.000Z

377

Heat rejection system  

DOE Patents [OSTI]

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

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

1980-01-01T23:59:59.000Z

378

Passive solar space heating  

SciTech Connect (OSTI)

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

Balcomb, J.D.

1980-01-01T23:59:59.000Z

379

EXTENSION CENTER FOR COMMUNITY VITALITY Continuing the Trend: The Brain Gain  

E-Print Network [OSTI]

EXTENSION CENTER FOR COMMUNITY VITALITY Continuing the Trend: The Brain Gain of the Newcomers Fellow, University of Minnesota Extension Center for Community Vitality #12;Brain Gain 2010 i Report Reviewers: Neil Linscheid Scott Chazdon Continuing the Trend: The Brain Gain of the Newcomers A GENERATIONAL

Minnesota, University of

380

Appropriate Realisation of MIMO Gain-Scheduled Controllers W.E. Leithead  

E-Print Network [OSTI]

Appropriate Realisation of MIMO Gain-Scheduled Controllers D.J.Leith W.E. Leithead Department characteristics of a controller designed by the gain-scheduling approach can be strongly dependent realisations for general MIMO gain-scheduled controllers. An extended local linear equivalence condition

Duffy, Ken

Note: This page contains sample records for the topic "heat gain coefficient" 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

Interpolated versus Polytopic Gain Scheduling Control Laws for Fin/Rudder Roll Stabilisation of Ships  

E-Print Network [OSTI]

Interpolated versus Polytopic Gain Scheduling Control Laws for Fin/Rudder Roll Stabilisation be done through the use of gain-scheduling (GS) control law. In this study, a GS-control law is obtained and a desired stabilisation quality factor. Gain scheduling is a way to obtain parameter dependent controllers

Paris-Sud XI, Université de

382

A GAIN SCHEDULED CONTROL LAW FOR FIN/RUDDER ROLL STABILISATION OF SHIPS  

E-Print Network [OSTI]

A GAIN SCHEDULED CONTROL LAW FOR FIN/RUDDER ROLL STABILISATION OF SHIPS Hervé Tanguy , Guy Lebret leads to a gain-scheduled control law. The synthesis is based on multi-objective optimisation stabilisation; H control; Gain Scheduled Control; polytopic representation; LMI. 1. INTRODUCTION A major

Paris-Sud XI, Université de

383

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

SciTech Connect (OSTI)

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

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

2014-01-01T23:59:59.000Z

384

Heat transfer measurements in a two-pass square duct via a transient liquid crystal image method  

E-Print Network [OSTI]

to obtain heat transfer coefficients. Heat transfer measurement distributions at 3 Reynolds numbers (10,000, 25,000, and 50,000) were studied. There were two geometric surface rib patterns attached to the channel. First was a 90° continuous rib...

Luna, Jesus Arturo

2000-01-01T23:59:59.000Z

385

Microchannel Heat Exchangers with Carbon Dioxide  

SciTech Connect (OSTI)

The objective of the present study was to determine the performance of CO{sub 2} microchannel evaporators and gas coolers in operational conditions representing those of residential heat pumps. A set of breadboard prototype microchannel evaporators and gas coolers was developed and tested. The refrigerant in the heat exchangers followed a counter cross-flow path with respect to the airflow direction. The test conditions corresponded to the typical operating conditions of residential heat pumps. In addition, a second set of commercial microchannel evaporators and gas coolers was tested for a less comprehensive range of operating conditions. The test results were reduced and a comprehensive data analysis, including comparison with the previous studies in this field, was performed. Capacity and pressure drop of the evaporator and gas cooler for the range of parameters studied were analyzed and are documented in this report. A gas cooler performance prediction model based on non-dimensional parameters was also developed and results are discussed as well. In addition, in the present study, experiments were conducted to evaluate capacities and pressure drops for sub-critical CO{sub 2} flow boiling and transcritical CO{sub 2} gas cooling in microchannel heat exchangers. An extensive review of the literature failed to indicate any previous systematic study in this area, suggesting a lack of fundamental understanding of the phenomena and a lack of comprehensive data that would quantify the performance potential of CO{sub 2} microchannel heat exchangers for the application at hand. All experimental tests were successfully conducted with an energy balance within {+-}3%. The only exceptions to this were experiments at very low saturation temperatures (-23 C), where energy balances were as high as 10%. In the case of evaporators, it was found that a lower saturation temperature (especially when moisture condensation occurs) improves the overall heat transfer coefficient significantly. However, under such conditions, air side pressure drop also increases when moisture condensation occurs. An increase in airflow rate also increases the overall heat transfer coefficient. Air side pressure drop mainly depends on airflow rate. For the gas cooler, a significant portion of the heat transfer occurred in the first heat exchanger module on the refrigerant inlet side. The temperature and pressure of CO{sub 2} significantly affect the heat transfer and fluid flow characteristics due to some important properties (such as specific heat, density, and viscosity). In the transcritical region, performance of CO{sub 2} strongly depends on the operating temperature and pressure. Semi-empirical models were developed for predictions of CO{sub 2} evaporator and gas cooler system capacities. The evaporator model introduced two new factors to account for the effects of air-side moisture condensate and refrigerant outlet superheat. The model agreed with the experimental results within {+-}13%. The gas cooler model, based on non-dimensional parameters, successfully predicted the experimental results within {+-}20%. Recommendations for future work on this project include redesigning headers and/or introducing flow mixers to avoid flow mal-distribution problems, devising new defrosting techniques, and improving numerical models. These recommendations are described in more detail at the end of this report.

Zhao, Y.; Ohadi, M.M.; Radermacher, R.

2001-09-15T23:59:59.000Z

386

Peltier heats in cryolite melts with alumina  

SciTech Connect (OSTI)

The Seebeck coefficient was measured for cells with electrolytes of molten mixtures of sodium fluoride and aluminum fluoride saturated with alumina. The electrodes were either a pair of oxygen electrodes or a pair of aluminum electrodes. For the molar ratio NaF/AlF{sub 3} equal to 1.8, 1.2 and 1.0, the authors obtained the Seebeck coefficients {minus}1.80 mV K{sup {minus}1} at 971 C, {minus}1.63 mV K{sup {minus}1} at 813.6 C and {minus}0.583 mV K{sup {minus}1} at 758 C, respectively, for the oxygen electrodes. For the aluminum electrodes, the authors obtained the Seebeck coefficient {minus}1.23 mV K{sup {minus}1} at 962 C, for the molar ratio NaF/AlF{sub 3} equal to 1.8. The results suggest that there is a substantial reversible heat consumption at the anode during aluminum electrolysis and a large reversible heat production at the cathode. The highest temperature in the Hall-Heroult cell is then closer to the cathode than the anode. The transported entropies of Al{sup 3+} and O{sup 2{minus}} were calculated to be 77 J mol{sup {minus}1} K{sup {minus}1} and 10 J mol{sup {minus}1} K{sup {minus}1}, respectively, when the molar ratio NaF/AlF{sub 3} was equal to 1.0.

Flem, B.E.; Ratkje, S.K.; Sterten, A. [Univ. of Trondheim (Norway)

1996-10-01T23:59:59.000Z

387

Film cooling and heat transfer of steam through an inclined injection hole  

E-Print Network [OSTI]

transfer coefficient at blowing rate M 0. 5 . . . . . . . . . . . . . . . . 37 NOMENCLATURE Symbol Description area circumference of the cross sectional area Cp D E, , Es, Es drag coefficient specific heat diameter of the injection hole minor... the experimental data at low blowing rates; however, the extension to higher injection rates is not correct, and an injected fluid other than air is not discussed. Goldstein [2] reviewed a number of semi- empirical correlations and predictions for two...

Chen, Hun Way

1983-01-01T23:59:59.000Z

388

Hydrodynamic granular segregation induced by boundary heating and shear  

E-Print Network [OSTI]

Segregation induced by a thermal gradient of an impurity in a driven low-density granular gas is studied. The system is enclosed between two parallel walls from which we input thermal energy to the gas. We study here steady states occurring when the inelastic cooling is exactly balanced by some external energy input (stochastic force or viscous heating), resulting in a uniform heat flux. A segregation criterion based on Navier-Stokes granular hydrodynamics is written in terms of the tracer diffusion transport coefficients, whose dependence on the parameters of the system (masses, sizes and coefficients of restitution) is explicitly determined from a solution of the inelastic Boltzmann equation. The theoretical predictions are validated by means of Monte Carlo and molecular dynamics simulations, showing that Navier-Stokes hydrodynamics produces accurate segregation criteria even under strong shearing and/or inelasticity.

Francisco Vega Reyes; Vicente Garzó; Nagi Khalil

2014-04-28T23:59:59.000Z

389

Heat pipes and use of heat pipes in furnace exhaust  

DOE Patents [OSTI]

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

Polcyn, Adam D. (Pittsburgh, PA)

2010-12-28T23:59:59.000Z

390

Proceedings of Heat Transfer 2003: ASME Summer Heat Transfer Conference  

E-Print Network [OSTI]

Proceedings of Heat Transfer 2003: ASME Summer Heat Transfer Conference Las Vegas, Nevada, USA July 21-23, 2003 HT2003-47449 HEAT TRANSFER FROM A MOVING AND EVAPORATING MENISCUS ON A HEATED SURFACE meniscus with complete evaporation of water without any meniscus break-up. The experimental heat transfer

Kandlikar, Satish

391

IMPLEMENTING GROUND SOURCE HEAT PUMP AND GROUND LOOP HEAT EXCHANGER  

E-Print Network [OSTI]

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

392

First university owned district heating system using biomass heat  

E-Print Network [OSTI]

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

Northern British Columbia, University of

393

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.

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

1981-01-01T23:59:59.000Z

394

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 intallation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer.

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

1984-01-01T23:59:59.000Z

395

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.

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

1984-01-01T23:59:59.000Z

396

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 faciliate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer.

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

1984-01-01T23:59:59.000Z

397

Microchannel heat sink assembly  

DOE Patents [OSTI]

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

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

1992-03-24T23:59:59.000Z

398

Heat transfer from combustion gases to a single row of closely spaced tubes in a swirl crossflow Stirling engine heater  

SciTech Connect (OSTI)

This paper describes an experimental program to determine the heat-transfer characteristics of a combustor and heat-exchange system in a hybrid solar receiver which utilizes a Stirling engine. The system consists of a swirl conbustor with a crossflow heat exchanger composed of a single row of 48 closely spaced curved tubes. In the present study, heat-transfer characteristics of the combustor/heat-exchanger system without a Stirling engine have been studied over a range of operating conditions and output levels using water as the working fluid. Non-dimensional heat-transfer coefficients based on total heat transfer have been obtained and are compared with available literature data. The results show significantly enhanced heat transfer for the present geometry and test conditions. Also, heat transfer along the length of the tubes is found to vary, the effect depending upon test condition.

Bankston, C.P.; Back, L.H.

1982-02-01T23:59:59.000Z

399

Simulation of a High Efficiency Multi-bed Adsorption Heat Pump  

SciTech Connect (OSTI)

Attaining high energy efficiency with adsorption heat pumps is challenging due to thermodynamic losses that occur when the sorbent beds are thermally cycled without effective heat recuperation. The multi-bed concept described here effectively transfers heat from beds being cooled to beds being heated, which enables high efficiency in thermally driven heat pumps. A simplified lumped-parameter model and detailed finite element analysis are used to simulate the performance of an ammonia-carbon sorption compressor, which is used to project the overall heat pump coefficient of performance. The effects of bed geometry and number of beds on system performance are explored, and the majority of the performance benefit is obtained with four beds. Results indicate that a COP of 1.24 based on heat input is feasible at AHRI standard test conditions for residential HVAC equipment. When compared on a basis of primary energy input, performance equivalent to SEER 13 or 14 are theoretically attainable with this system.

TeGrotenhuis, Ward E.; Humble, Paul H.; Sweeney, J. B.

2012-05-01T23:59:59.000Z

400

Iterative solution of ordinary differential equations with polynomial coefficients  

E-Print Network [OSTI]

ITERATIVE SOLUTION OF ORDINARY DIFFERENTIAL EQUATIONS WITH POLYNOMIAL COEFFICIENTS A Thesis By JIMMIE CHARLES RHEA FOREHAND Submitted to the Graduate College of the Texas A&M University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE August 1965 Major Subject Mathematics FAMILIES OF FIFTH ORDER RUNGE-KUTTA FORMULAS A Thesis By HARRY PAUL KONEN 4 0 0 IXI v 0 Approved as to style and content by: (Chairman of Committee) (Head of Departmen...

Forehand, Jimmie Charles Rhea

1965-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heat gain coefficient" 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

ARM: 10-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm  

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

10-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

Newsom, Rob; Goldsmith, John

402

ARM: 2-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm  

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

2-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

Sivaraman, Chitra; Flynn, Connor

403

ARM: 10-second Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm  

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

10-second Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

Sivaraman, Chitra; Flynn, Connor

404

ARM: 1-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm  

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

1-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

Sivaraman, Chitra; Flynn, Connor

405

NUMERICAL CALCULATIONS FOR THE ASYMPTOTIC, DIFFUSION DOMINATED MASS-TRANSFER COEFFICIENT IN PACKED BED REACTORS  

E-Print Network [OSTI]

Calculations for the Asymptotic, Diffusion Dominated Mass-Transfer Coefficient in Packed Bed Reactors

Fedkiw, Peter

2011-01-01T23:59:59.000Z

406

Solar heating system  

DOE Patents [OSTI]

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

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

1982-01-01T23:59:59.000Z

407

Improved solar heating systems  

DOE Patents [OSTI]

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

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

1980-05-16T23:59:59.000Z

408

Estimation of tracer diffusion coefficients of ions in aqueous solution  

SciTech Connect (OSTI)

Equations are given for estimating tracer diffusion coefficients D/sub i//sup 0/ of ions at infinite dilution in terms of limiting ionic conductances ..lambda../sub i//sup 0/. Also given are generalized Nernst-Hartley equations for binary and multicomponent diffusion coefficients D/sup 0/ and D/sub ij//sup 0/, respectively, at infinite dilution. Data, estimates, and correlations for ..lambda../sub i//sup 0/ at 25/sup 0/C and other temperatures are discussed. Estimated values of ..lambda../sub i//sup 0/ are tabulated from 0-300/sup 0/C for ions of waste isolation interest and for ions of economic interest in geothermal brines. Estimates of their tracer diffusion coefficients at infinite dilution are tabulated. A rule of thumb, good to a factor of 2, is presented. Very limited data (available only at 25/sup 0/C) indicate that D/sub i//D/sub i//sup 0/ generally declines as the concentration of salt or supporting electrolyte increases. 6 figures, 2 tables.

Miller, D.G.

1982-09-07T23:59:59.000Z

409

GAiN: Distributed Array Computation with Python  

SciTech Connect (OSTI)

Scientific computing makes use of very large, multidimensional numerical arrays - typically, gigabytes to terabytes in size - much larger than can fit on even the largest single compute node. Such arrays must be distributed across a "cluster" of nodes. Global Arrays is a cluster-based software system from Battelle Pacific Northwest National Laboratory that enables an efficient, portable, and parallel shared-memory programming interface to manipulate these arrays. Written in and for the C and FORTRAN programming languages, it takes advantage of high-performance cluster interconnections to allow any node in the cluster to access data on any other node very rapidly. The "numpy" module is the de facto standard for numerical calculation in the Python programming language, a language whose use is growing rapidly in the scientific and engineering communities. numpy provides a powerful N-dimensional array class as well as other scientific computing capabilities. However, like the majority of the core Python modules, numpy is inherently serial. Our system, GAiN (Global Arrays in NumPy), is a parallel extension to Python that accesses Global Arrays through numpy. This allows parallel processing and/or larger problem sizes to be harnessed almost transparently within new or existing numpy programs.

Daily, Jeffrey A.

2009-04-24T23:59:59.000Z

410

Enhancing optical gains in Si nanocrystals via hydrogenation and cerium ion doping  

SciTech Connect (OSTI)

We report optical gain enhancements in Si nanocrystals (Si-NCs) via hydrogenation and Ce{sup 3+} ion doping. Variable stripe length technique was used to obtain gains. At 0.3?W/cm{sup 2} pumping power density of pulsed laser, net gains were observed together with gain enhancements after hydrogenation and/or Ce{sup 3+} ion doping; gains after loss corrections were between 89.52 and 341.95?cm{sup ?1}; and the photoluminescence (PL) lifetime was found to decrease with the increasing gain enhancement. At 0.04?W/cm{sup 2} power density, however, no net gain was found and the PL lifetime increased with the increasing PL enhancement. The results were discussed according to stimulated and spontaneous excitation and de-excitation mechanisms of Si-NCs.

Wang, Dong-Chen; Li, Yan-Li; Song, Sheng-Chi; Guo, Wen-Ping; Lu, Ming, E-mail: minglu55@fudan.edu.cn [Department of Optical Science and Engineering, and Shanghai Ultra-Precision Optical Manufacturing Engineering Center, Fudan University, Shanghai 200433 (China); Chen, Jia-Rong [Department of Optical Science and Engineering, and Shanghai Ultra-Precision Optical Manufacturing Engineering Center, Fudan University, Shanghai 200433 (China); School of Information Engineering, Guizhou Minzu University, Guiyang 550025 (China)

2014-07-28T23:59:59.000Z

411

The effect of an evaporation suppressant upon the liquid film oxygen transfer coefficient  

E-Print Network [OSTI]

" ? By Winkler Method 32 Oxygen Transfer Coefficient At 21'C Using Distilled Water Without "Aquasave" ? By Winkler Method 33 Oxygen Transfer Coefficient At 36'C Using Distilled Water With "Aquasave" ? By Winkler Method 34 Oxygen Transfer Coefficient At 36'C... Using Distilled Water Without "Aquasave" ? By Winkler Method 35 Oxygen Transfer Coefficient At 21'C Using Blended Water With "Aquasave" ? By D. O. Meter 37 10. Oxygen Transfer Coefficient At 21'C Using Blended Water Without "Aquasave" ? By D. 0...

Amad, Mohamad Towfic

1967-01-01T23:59:59.000Z

412

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

E-Print Network [OSTI]

-807. (5) K. Kesavan. The Use of Dissociating Gases As the Working Fluid in Thermodynamic Power Conversion Cycles, Ph.D. thesis. Carnegie-Mellon University, 1978, Ann Arbor, MI: University Microfilms International, 1978. 5. Heat amplifier with a gas...ABSTRACT Chemical heat pumps utilize working fluids which undergo reversible chemical changes. Mechanically driven reactive heat pump cycles or, alternatively, hl~a: driven heat pumps in which either heat engine or heat pump working fluid...

Kirol, L. D.

413

Integrating preconcentrator heat controller  

DOE Patents [OSTI]

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

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

2007-10-16T23:59:59.000Z

414

Proceedings: Heat exchanger workshop  

SciTech Connect (OSTI)

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

Not Available

1987-07-01T23:59:59.000Z

415

Micro heat barrier  

DOE Patents [OSTI]

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

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

2003-08-12T23:59:59.000Z

416

Condensing Heating and Water Heating Equipment Workshop Location...  

Energy Savers [EERE]

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

417

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

Open Energy Info (EERE)

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

418

Economic Options for Upgrading Waste Heat  

E-Print Network [OSTI]

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

Erickson, D. C.

1983-01-01T23:59:59.000Z

419

Molecular heat pump  

E-Print Network [OSTI]

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

Dvira Segal; Abraham Nitzan

2005-10-11T23:59:59.000Z

420

Heat treatment furnace  

DOE Patents [OSTI]

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

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

2014-10-21T23:59:59.000Z

Note: This page contains sample records for the topic "heat gain coefficient" 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

Heat storage with CREDA  

SciTech Connect (OSTI)

The principle of operation of ETS or Electric Thermal Storage is discussed in this book. As can be seen by the diagram presented, heating elements buried deep within the core are energized during off-peak periods or periods of lower cost energy. These elements charge the core to a per-determined level, then during the on-peak periods when the cost of electricity is higher or demand is higher, the heat is extracted from the core. The author discusses how this technology has progressed to the ETS equipment of today; this being the finer control of charging rates and extraction of heat from the core.

Beal, T. (Fostoria Industries, Fostoria, OH (US))

1987-01-01T23:59:59.000Z

422

Heat pumps and under floor heating as a heating system for Finnish low-rise residential buildings.  

E-Print Network [OSTI]

??In bachelor’s thesis the study of under floor heating system with ground source heat pump for the heat transfers fluid heating is considered. The case… (more)

Chuduk, Svetlana

2010-01-01T23:59:59.000Z

423

Promotion of efficient heat pumps for heating (ProHeatPump)  

E-Print Network [OSTI]

Project Promotion of efficient heat pumps for heating (ProHeatPump) EIE/06/072 / S12.444283 Supplementary report: Heat pumps in Norway May 2009 Work Package 4: Policy context and measures Authors: Nils of the industry and markets in the ProHeatPump partner countries, and should provide useful comparisons

424

Experimental investigation on the photovoltaic-thermal solar heat pump air-conditioning system on water-heating mode  

SciTech Connect (OSTI)

An experimental study on operation performance of photovoltaic-thermal solar heat pump air-conditioning system was conducted in this paper. The experimental system of photovoltaic-thermal solar heat pump air-conditioning system was set up. The performance parameters such as the evaporation pressure, the condensation pressure and the coefficient of performance (COP) of heat pump air-conditioning system, the water temperature and receiving heat capacity in water heater, the photovoltaic (PV) module temperature and the photovoltaic efficiency were investigated. The experimental results show that the mean photovoltaic efficiency of photovoltaic-thermal (PV/T) solar heat pump air-conditioning system reaches 10.4%, and can improve 23.8% in comparison with that of the conventional photovoltaic module, the mean COP of heat pump air-conditioning system may attain 2.88 and the water temperature in water heater can increase to 42 C. These results indicate that the photovoltaic-thermal solar heat pump air-conditioning system has better performances and can stably work. (author)

Fang, Guiyin; Hu, Hainan; Liu, Xu [Department of Physics, Nanjing University, Nanjing 210093 (China)

2010-09-15T23:59:59.000Z

425

Photovoltaic roof heat flux  

E-Print Network [OSTI]

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

Samady, Mezhgan Frishta

2011-01-01T23:59:59.000Z

426

Composite heat damage assessment  

SciTech Connect (OSTI)

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

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

1993-12-31T23:59:59.000Z

427

Solar Heating Contractor Licensing  

Broader source: Energy.gov [DOE]

Michigan offers a solar heating contractor specialty license to individuals who have at least three years of experience installing solar equipment under the direction of a licensed solar contractor...

428

Passive solar heating analysis  

SciTech Connect (OSTI)

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

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

1984-01-01T23:59:59.000Z

429

Wood Heating Fuel Exemption  

Broader source: Energy.gov [DOE]

This statute exempts from the state sales tax all wood or "refuse-derived" fuel used for heating purposes. The law does not make any distinctions about whether the qualified fuels are used for...

430

Asymptotic normalization coefficients for B-10->Be-9+p  

E-Print Network [OSTI]

started the Asymptotic normalization coefficient A. M. Mukhamedzhanov, H. L. Clark, C. A. Gagliardi, Y.-W Cyclotron Institute, Texas A&M University V. Burjan, J. Cejpek Institute for Nuclear Physics, Czech Academ F. Carstoi Institute of Atomic...! the 7Be(p ,g)8B radiative capture cross section at ver astrophysics. @S0556-2813~97!02109-2# PACS number~s!: 25.70.Hi, 21.10.Jx, 24.10.Ht, 25.70.B I. INTRODUCTION Despite considerable experimental and theoretical progress in determining...

Mukhamedzhanov, AM; Clark, HL; Gagliardi, Carl A.; Lui, YW; Trache, L.; Tribble, Robert E.; Xu, HM; Zhou, XG; Burjan, V.; Cejpek, J.; Kroha, V.; Carstoiu, F.

1997-01-01T23:59:59.000Z

431

Heat Waves, Global Warming, and Mitigation  

E-Print Network [OSTI]

Heat Waves, Global Warming, and Mitigation Ann E. Carlson*II. HEAT WAVE DEFINITIONS .. A . HCHANGE AND HEAT WAVES .. CLIMATE III. IV. HEAT

Carlson, Ann E.

2008-01-01T23:59:59.000Z

432

Heat flux limiting sleeves  

DOE Patents [OSTI]

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

Harris, William G. (Tampa, FL)

1985-01-01T23:59:59.000Z

433

NGNP Process Heat Utilization: Liquid Metal Phase Change Heat Exchanger  

SciTech Connect (OSTI)

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

Piyush Sabharwall; Mike Patterson; Vivek Utgikar; Fred Gunnerson

2008-09-01T23:59:59.000Z

434

Radial flow heat exchanger  

DOE Patents [OSTI]

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

Valenzuela, Javier (Hanover, NH)

2001-01-01T23:59:59.000Z

435

Convective heat flow probe  

DOE Patents [OSTI]

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

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

1984-01-09T23:59:59.000Z

436

Heat Transfer in Complex Fluids  

SciTech Connect (OSTI)

Amongst the most important constitutive relations in Mechanics, when characterizing the behavior of complex materials, one can identify the stress tensor T, the heat flux vector q (related to heat conduction) and the radiant heating (related to the radiation term in the energy equation). Of course, the expression 'complex materials' is not new. In fact, at least since the publication of the paper by Rivlin & Ericksen (1955), who discussed fluids of complexity (Truesdell & Noll, 1992), to the recently published books (Deshpande et al., 2010), the term complex fluids refers in general to fluid-like materials whose response, namely the stress tensor, is 'non-linear' in some fashion. This non-linearity can manifest itself in variety of forms such as memory effects, yield stress, creep or relaxation, normal-stress differences, etc. The emphasis in this chapter, while focusing on the constitutive modeling of complex fluids, is on granular materials (such as coal) and non-linear fluids (such as coal-slurries). One of the main areas of interest in energy related processes, such as power plants, atomization, alternative fuels, etc., is the use of slurries, specifically coal-water or coal-oil slurries, as the primary fuel. Some studies indicate that the viscosity of coal-water mixtures depends not only on the volume fraction of solids, and the mean size and the size distribution of the coal, but also on the shear rate, since the slurry behaves as shear-rate dependent fluid. There are also studies which indicate that preheating the fuel results in better performance, and as a result of such heating, the viscosity changes. Constitutive modeling of these non-linear fluids, commonly referred to as non-Newtonian fluids, has received much attention. Most of the naturally occurring and synthetic fluids are non-linear fluids, for example, polymer melts, suspensions, blood, coal-water slurries, drilling fluids, mud, etc. It should be noted that sometimes these fluids show Newtonian (linear) behavior for a given range of parameters or geometries; there are many empirical or semi-empirical constitutive equations suggested for these fluids. There have also been many non-linear constitutive relations which have been derived based on the techniques of continuum mechanics. The non-linearities oftentimes appear due to higher gradient terms or time derivatives. When thermal and or chemical effects are also important, the (coupled) momentum and energy equations can give rise to a variety of interesting problems, such as instability, for example the phenomenon of double-diffusive convection in a fluid layer. In Conclusion, we have studied the flow of a compressible (density gradient type) non-linear fluid down an inclined plane, subject to radiation boundary condition. The heat transfer is also considered where a source term, similar to the Arrhenius type reaction, is included. The non-dimensional forms of the equations are solved numerically and the competing effects of conduction, dissipation, heat generation and radiation are discussed. It is observed that the velocity increases rapidly in the region near the inclined surface and is slower in the region near the free surface. Since R{sub 7} is a measure of the heat generation due to chemical reaction, when the reaction is frozen (R{sub 7}=0.0) the temperature distributions would depend only on R{sub 1}, and R{sub 2}, representing the effects of the pressure force developed in the material due to the distribution, R{sub 3} and R{sub 4} viscous dissipation, R{sub 5} the normal stress coefficient, R{sub 6} the measure of the emissivity of the particles to the thermal conductivity, etc. When the flow is not frozen (RP{sub 7} > 0) the temperature inside the flow domain is much higher than those at the inclined and free surfaces. As a result, heat is transferred away from the flow toward both the inclined surface and the free surface with a rate that increases as R{sub 7} increases. For a given temperature, an increase in {zeta} implies that the activation energy is smaller and thus, the reaction ra

Mehrdad Massoudi

2012-01-01T23:59:59.000Z

437

Solar air heating system for combined DHW and space heating  

E-Print Network [OSTI]

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

438

Heat exchanger device and method for heat removal or transfer  

DOE Patents [OSTI]

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

Koplow, Jeffrey P. (San Ramon, CA)

2012-07-24T23:59:59.000Z

439

Heat exchanger device and method for heat removal or transfer  

DOE Patents [OSTI]

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

Koplow, Jeffrey P

2013-12-10T23:59:59.000Z

440

Enhanced shell-and-tube heat eschangers for the power and process industries. Final report  

SciTech Connect (OSTI)

Single-tube pool boiling tests were performed with saturated pure refrigerants and binary mixtures of refrigerants. Generally, with pure refrigerants, the High Flux surface performed better at the higher heat fluxes compared to the Turbo-B tube, and both enhanced surfaces performed significantly better than smooth surface. In tests of R-11/R-113 mixtures, the enhanced surfaces had much less degradation in heat transfer coefficient due to mixture effects compared to smooth tubes; the largest degradation occurred at a mixture of 25% R-11/75% R-113. Under boiling in saturated aqueous solution of calcium sulfate, with a single tube, effects of fouling were more pronounced at the higher heat fluxes for all surfaces. Two staggered tube bundles were tested with tube pitch-diameter ratios of 1.17 and 1.50. For the pure refrigerant, tests on the smooth-tube bundle indicated that the effects on the heat transfer coefficient of varying mass flux, quality, and tube-bundle geometry were small, except at low heat fluxes. Neither enhanced surface showed any effect with changing mass flux or quality. The binary mixture bundle-boiling tests had results that were very similar to those obtained with the pure refrigerants. When boiling a refrigerant-oil mixture, all three surfaces (smooth, High Flux, and Turbo-B) experienced a degradation in its heat transfer coefficient; no surface studied was found to be immune or vulnerable to the presence of oil than another surface.

Bergles, A.E.; Jensen, M.K.; Somerscales, E.F.; Curcio, L.A. Jr.; Trewin, R.R.

1994-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "heat gain coefficient" 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

E-Print Network 3.0 - antipsychotic-induced weight gain Sample...  

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

movement disorders (AIMDs) have been collectively known as extrapyramidal syndromes (EPS... seen with typical antipsychotics (e.g., weight gain, hyperlipidemia, and...

442

E-Print Network 3.0 - antipsychotics-induced weight gain Sample...  

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

movement disorders (AIMDs) have been collectively known as extrapyramidal syndromes (EPS... seen with typical antipsychotics (e.g., weight gain, hyperlipidemia, and...

443

Problemstellung "Brain Drain" bzw. "Brain Gain" in der Region Niederösterreich-Mitte.  

E-Print Network [OSTI]

??Die vorliegende Diplomarbeit befasst sich mit dem Thema des „Brain Drain“ und „Brain Gain“ in der Region Niederösterreich Mitte. Unter "Brain Drain" versteht man die… (more)

Binder, Paul

2012-01-01T23:59:59.000Z

444

Post-Genomics Nanotechnology Is Gaining Momentum: Nanoproteomics and Applications in Life Sciences  

E-Print Network [OSTI]

Post-Genomics Nanotechnology Is Gaining Momentum: Nanoproteomics and Applications in Life Sciences of nanotechnology applications, including nanoporous structures, functionalized nanoparticles, quantum dots

Tan, Weihong

445

Methanol-based heat pump for solar heating, cooling, and storage. Phase III. Final report  

SciTech Connect (OSTI)

The reaction of CH/sub 3/OH vapor with solid (pellet) CaCl/sub 2/ to form the solid phase compound CaCll/sub 2/ . 2CH/sub 3/OH can be used as the basis of a combined solar heat pump/thermal energy storage system. Such a system is capable of storing heat indefinitely at ambient temperature, and can be used for space and domestic hot water heating, and for air conditioning with forced air (dry) heat rejection. It combines all features required of a residential or commercial space conditioning system except for solar collection. A detailed thermal analysis shows that the coefficient of performance for heating is greater than 1.5, and for cooling, greater than 0.5. This has been confirmed by direct experimental measurement on an engineering development test unit (EDTU). The experimental rate of CH/sub 3/OH absorption is a strong function of the absorber-evaporator temperature difference. The minimum practical hourly rate, 0.10 moles CH/sub 3/OH per mole CaCl/sub 2/, was observed with the salt-bed heat transfer fluid at 40/sup 0/C and the CH/sub 3/OH evaporator at -15/sup 0/C. a detailed performance and economic analysis was carried out for a system operated in Washington, DC. With 25 square meters of evacuated tube solar collectors, the CaCl/sub 2/-CH/sub 3/OH chemical heat pump should be capable of meeting over 90% of the cooling load, 80% of the heating load, and 70% of the domestic hot water load with nonpurchased energy in a typical well-insulated single family residence, thus saving about $600 per year. In small-scale production, the installed cost of the system, including solar collectors and backup, is estimated to be about $10,000 greater than a conventional heating and cooling system, and a much lower cost should be possible in the longer term.

Offenhartz, P O'D; Rye, T V; Malsberger, R E; Schwartz, D

1981-03-01T23:59:59.000Z

446

A comparison of the heat transfer capabilities of two manufacturing methods for high heat flux water-cooled devices  

SciTech Connect (OSTI)

An experimental program was undertaken to compare the heat transfer characteristics of water-cooled copper devices manufactured via conventional drilled passage construction and via a technique whereby molten copper is cast over a network of preformed cooling tubes. Two similar test blocks were constructed; one using the drilled passage technique, the other via casting copper over Monel pipe. Each test block was mounted in a vacuum system and heated uniformly on the top surface using a swept electron beam. From the measured absorbed powers and resultant temperatures, an overall heat transfer coefficient was calculated. The maximum heat transfer coefficient calculated for the case of the drilled passage test block was 2534 Btu/hr/ft/sup 2///sup 0/F. This corresponded to an absorbed power density of 320 w/cm/sup 2/ and resulted in a maximum recorded copper temperature of 346/sup 0/C. Corresponding figures for the cast test block were 363 Btu/hr/ft/sup 2///sup 0/F, 91 w/cm/sup 2/, and 453/sup 0/C.

McKoon, R.H.

1986-10-01T23:59:59.000Z

447

Calculation of combined diffusion coefficients in SF{sub 6}-Cu mixtures  

SciTech Connect (OSTI)

Diffusion coefficients play an important role in the description of the transport of metal vapours in gas mixtures. This paper is devoted to the calculation of four combined diffusion coefficients, namely, the combined ordinary diffusion coefficient, combined electric field diffusion coefficient, combined temperature diffusion coefficient, and combined pressure diffusion coefficient in SF{sub 6}-Cu mixtures at temperatures up to 30?000?K. These four coefficients describe diffusion due to composition gradients, applied electric fields, temperature gradients, and pressure gradients, respectively. The influence of copper fluoride and sulfide species on the diffusion coefficients is shown to be negligible. The effect of copper proportion and gas pressures on these diffusion coefficients is investigated. It is shown that increasing the proportion of copper generally increases the magnitude of the four diffusion coefficients, except for copper mole fractions of 90% or more. It is further found that increasing the pressure reduces the magnitude of the coefficients, except for the combined temperature diffusion coefficient, and shifts the maximum of all four coefficients towards higher temperatures. The results presented in this paper can be applied to the simulation of high-voltage circuit breaker arcs.

Zhong, Linlin; Wang, Xiaohua, E-mail: xhw@mail.xjtu.edu.cn; Rong, Mingzhe, E-mail: mzrong@mail.xjtu.edu.cn; Wu, Yi [State Key Laboratory of Electrical Insulation and Power Equipment, School of Electrical Engineering, Xi'an Jiaotong University, Xi'an 710049 (China); Murphy, Anthony B. [CSIRO Manufacturing Flagship, P.O. Box 218, Lindfield, NSW 2070 (Australia)

2014-10-15T23:59:59.000Z

448

Grid-region heat transfer in a gas solid fluidized bed  

SciTech Connect (OSTI)

The grid region heat transfer to a horizontal tube in a gas-solid fluidized bed was studied experimentally and theoretically. A preliminary experimental study was first conducted to investigate semi-quantitatively the heat transfer characteristics in the grid region as well as in the bubbling region of the gas-solid fluidized bed using a simple hot water circulation system. Experimental parameters included particle size, static bed height, superficial gas velocity, distributor open area, distributor hole sizes, distributor hole numbers, and vertical locations of the heating tube. An additional experimental study was then carried out to study quantitatively the heat transfer coefficient in each grid region phase, i.e., jet phase, emulsion phase and dead phase using an artificial jet and an electrically heated tube. The observed heat transfer coefficients for each phase were correlated as a function of experimental parameters. The observed results are also compared with results estimated from a heat transfer model, which is based on plausible heat transfer mechanisms in the grid region of a gas-solid fluidized bed.

Wang, R.C.

1986-01-01T23:59:59.000Z

449

Some investigations on the enhancement of boiling heat transfer from planer surface embedded with continuous open tunnels  

SciTech Connect (OSTI)

Boiling heat transfer from a flat surface can be enhanced if continuous open tunnel type structures are embedded in it. Further, improvement of boiling heat transfer from such surfaces has been tried by two separate avenues. At first, inclined tunnels are embedded over the solid surface and an effort is made to optimize the tunnel inclination for boiling heat transfer. Surfaces are manufactured in house with four different inclinations of the tunnels with or without a reentrant circular pocket at the end of the tunnel. Experiments conducted in the nucleate boiling regime showed that 45 deg inclination of the tunnels for both with and without base geometry provides the highest heat transfer coefficient. Next, active fluid rotation was imposed to enhance the heat transfer from tunnel type surfaces with and without the base geometry. Rotational speed imparted by mechanical stirrer was varied over a wide range. It was observed that fluid rotation enhances the heat transfer coefficient only up to a certain value of stirrer speed. Rotational speed values, beyond this limit, reduce the boiling heat transfer severely. A comparison shows that embedding continuous tunnel turns out to be a better option for the increase of heat transfer coefficient compared to the imposition of fluid rotation. But the behavior of inclined tunnels under the action of fluid rotation is yet to be established and can be treated as a future scope of the work. (author)

Das, A.K.; Das, P.K.; Saha, P. [Department of Mechanical Engineering, Indian Institute of Technology, Kharagpur 721 302 (India)

2010-11-15T23:59:59.000Z

450

Effect of translucence of engineering ceramics on heat transfer in diesel engines  

SciTech Connect (OSTI)

This report describes the experimental portion of a broader study undertaken to assess the effects of translucence of ceramic materials used as thermal barrier coatings in diesel engines. In an earlier analytical work a parametric study was performed, varying several radiative properties over ranges typical of engineering ceramics, thereby identifying the most important radiative properties and their impact on in-cylinder heat transfer. In the current study these properties were experimentally determined for several specific zirconia coatings considered for thermal barrier applications in diesel engines. The methodology of this study involved formulation of a model capable of describing radiative transfer through a semitransparent medium as a function of three independent model parameters, ie, absorption coefficient, scattering coefficient and refractive index. For the zirconia-based ceramics investigated in this study, it was concluded that for usual coating thicknesses (1.5--2.5 mm) these ceramics are optically thick and hence, are effective as radiative heat transfer barriers. These ceramics possess high scattering coefficients and low absorption coefficients causing them to be highly reflective (60-80%) in the spectral region where thermal radiation is important. The performance of the investigated ceramics and the mechanism of heat transfer were found to depend on surface condition, specifically on soot deposition. Thus, to insure the optimum thermal barrier operation for either clean or heavily sooted surfaces, a ceramic material with high scattering coefficient provides the best choice.

Wahiduzzaman, S.; Morel, T. (Integral Technologies, Inc., Westmont, IL (United States))

1992-04-01T23:59:59.000Z

451

Effect of translucence of engineering ceramics on heat transfer in diesel engines. Final report  

SciTech Connect (OSTI)

This report describes the experimental portion of a broader study undertaken to assess the effects of translucence of ceramic materials used as thermal barrier coatings in diesel engines. In an earlier analytical work a parametric study was performed, varying several radiative properties over ranges typical of engineering ceramics, thereby identifying the most important radiative properties and their impact on in-cylinder heat transfer. In the current study these properties were experimentally determined for several specific zirconia coatings considered for thermal barrier applications in diesel engines. The methodology of this study involved formulation of a model capable of describing radiative transfer through a semitransparent medium as a function of three independent model parameters, ie, absorption coefficient, scattering coefficient and refractive index. For the zirconia-based ceramics investigated in this study, it was concluded that for usual coating thicknesses (1.5--2.5 mm) these ceramics are optically thick and hence, are effective as radiative heat transfer barriers. These ceramics possess high scattering coefficients and low absorption coefficients causing them to be highly reflective (60-80%) in the spectral region where thermal radiation is important. The performance of the investigated ceramics and the mechanism of heat transfer were found to depend on surface condition, specifically on soot deposition. Thus, to insure the optimum thermal barrier operation for either clean or heavily sooted surfaces, a ceramic material with high scattering coefficient provides the best choice.

Wahiduzzaman, S.; Morel, T. [Integral Technologies, Inc., Westmont, IL (United States)

1992-04-01T23:59:59.000Z

452

Evaluation of solar collectors for heat pump applications. Final report  

SciTech Connect (OSTI)

The study was initiated to evaluate the potential utility of very low cost (possibly unglazed and uninsulated) solar collectors to serve as both heat collection and rejection devices for a liquid source heat pump. The approach consisted of exercising a detailed analytical simulation of the complete heat pump/solar collector/storage system against heating and cooling loads derived for typical single-family residences in eight US cities. The performance of each system was measured against that of a conventional air-to-air heat pump operating against the same loads. In addition to evaluation of solar collector options, the study included consideration of water tanks and buried pipe grids to provide thermal storage. As a supplement to the analytical tasks, the study included an experimental determination of night sky temperature and convective heat transfer coefficients for surfaces with dimensions typical of solar collectors. The experiments were conducted in situ by placing the test apparatus on the roofs of houses in the Denver, Colorado, area. (MHR)

Skartvedt, Gary; Pedreyra, Donald; McMordle, Dr., Robert; Kidd, James; Anderson, Jerome; Jones, Richard

1980-08-01T23:59:59.000Z

453

Condensation coefficients in plasma sputtering Pascal Brault , Anne-Lise Thomann, Jean-Philippe  

E-Print Network [OSTI]

Condensation coefficients in plasma sputtering deposition Pascal Brault §, Anne-Lise Thomann, Jean Backscattering Spectrom- etry are combined to determine condensation coefficients for plasma sputtering depo- sition. The method is applied for palladium deposition onto various substrates and condensation

Boyer, Edmond

454

Environmental Radioactivity 56 (2001) 327340 Radon progeny dose conversion coefficients for  

E-Print Network [OSTI]

Journal of Environmental Radioactivity 56 (2001) 327­340 Radon progeny dose conversion coefficients; Dose conversion coefficients; Scaling factors; Radon progeny 1. Introduction Epidemiological studies cancer associated with exposure to radon progeny (Lubin, 1988). More recently, Lubin et al (1994

Yu, K.N.

455

Calculating and reporting changes in net heat of combustion of wood fuel  

SciTech Connect (OSTI)

There is often confusion when reporting net heat of combustion changes in wood fuel due to changes in moisture content (MC) of the fuel. This paper was written to identify and clarify the bases on which changes in net heat of combustion can be calculated. Formulae for calculating changes in net heat of combustion of wood fuel due to MC changes are given both on a per unit weight of fuel basis and on an actual gain basis. Examples which illustrate the difference in the two reporting approaches, as well as the importance of both approaches, are presented. (Refs. 7).

Harris, R.A.; McMinn, J.W.; Payne, F.A.

1986-06-01T23:59:59.000Z

456

Heat and Power Systems Design  

E-Print Network [OSTI]

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

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

457

Heat distribution ceramic processing method  

DOE Patents [OSTI]

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

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

2001-01-01T23:59:59.000Z

458

Study of the Effects of Surface Morphology and Droplet Growth Dynamics on Condensation Heat Transfer  

E-Print Network [OSTI]

system 2 on Sample 3 (50??m micropillar spacing hybrid surface) ............................................................................................... 66 Figure 24. Environmental scanning electron microscopy (ESEM) time- sequence images... tension gradients to promote and induce a droplet removal mechanism. They concluded that their gradient surface exhibited a higher heat transfer coefficient than a hydrophobic silane based surface. More recently, environmental scanning electron...

Yao, Chun-Wei

2014-04-23T23:59:59.000Z

459

An experimental, theoretical and numerical investigation of corona wind heat transfer enhancement  

E-Print Network [OSTI]

Corona wind heat transfer enhancement is a non-mechanical means of augmenting transfer coefficients in free and low-velocity convection flow fields. Ions formed near the surface of a high-voltage electrode are forced along the electric field lines...

Owsenek, Brian Leonard

1993-01-01T23:59:59.000Z

460

UW -Center for Intelligent Materials and Systems 1 1-D Heat Flow Measurement  

E-Print Network [OSTI]

: Calibrate Seebeck Coefficient for TFTC(Thin Film Thermocouples) x y Heater (70°C) Water (19°C) #12;UW ANSYS Simulation Used Data Water Temp. 2 Measured Temp. (Channel 14, 15) Heater size Assumption. Factor 2.258 #12;UW - Center for Intelligent Materials and Systems 3 2-D Heat Flow Measurement x y Heater

Taya, Minoru

Note: This page contains sample records for the topic "heat gain coefficient" 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

Acoustical heat pumping engine  

DOE Patents [OSTI]

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

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

1983-08-16T23:59:59.000Z

462

Air heating system  

DOE Patents [OSTI]

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

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

1983-03-01T23:59:59.000Z

463

Solar industrial process heat  

SciTech Connect (OSTI)

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

Lumsdaine, E.

1981-04-01T23:59:59.000Z

464

Acoustical heat pumping engine  

DOE Patents [OSTI]

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

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

1983-08-16T23:59:59.000Z

465

PRODUCTIVITY GAINS IN U.S. FISHERIES . FREDERICK W. BELL AND RICHARD K. KINOSHITA I  

E-Print Network [OSTI]

PRODUCTIVITY GAINS IN U.S. FISHERIES . FREDERICK W. BELL AND RICHARD K. KINOSHITA I ABSTRACT Changes in productivity or annual landings per fisherman help to determine the economic welfare of the fishing industry. Although a study of productivity gains in various U.S. fishing fleets over the last 20

466

A low power, high dynamic-range, broadband variable gain amplifier for an ultra wideband receiver  

E-Print Network [OSTI]

gain steps. The gain control scheme includes fine tuning (2dB/step) by changing the bias voltage of the proposed programmable current mirror, and coarse tuning (14dB/step) by switching on/off the source degeneration resistors in the differential pairs...

Chen, Lin

2007-09-17T23:59:59.000Z

467

Study in Indonesia and gain credit towards your degree! DevelopmentStudiesImmersionProgram ACICIS  

E-Print Network [OSTI]

Study in Indonesia and gain credit towards your degree! DevelopmentStudiesImmersionProgram ACICIS an internship in Indonesia! © Photograph by James Walsh #12;w w w . a c i c i s . m u r d o c h . e d u . a u development issues in Indonesia while also gaining im- portant practical skills related to advocacy

468

Study in Indonesia and gain credit towards your degree! Unleash your creativity...  

E-Print Network [OSTI]

Study in Indonesia and gain credit towards your degree! Unleash your creativity... Spend a semester at Indonesia's premiere institution for visual and performing arts... StudytheArtsinIndonesia Study in Indonesia and gain credit towards your degree! ACICIS #12;w w w . a c i c i s . m u r d o c h . e d u . a u

469

Gain Scheduling Control Design of an Erbium-Doped Fibre Amplifier by Pump Compensation  

E-Print Network [OSTI]

Gain Scheduling Control Design of an Erbium-Doped Fibre Amplifier by Pump Compensation Min Ding amplifier's (EDFA's) dynamics. We demonstrate a gain scheduling scheme on a PID controller that minimizes- pensation. The scheduled controller requires only three easily accessible parameters: the total input power

Pavel, Lacra

470

Robust Gain Scheduling techniques for Adaptive control Patrice Antoinette and Gilles Ferreres  

E-Print Network [OSTI]

Robust Gain Scheduling techniques for Adaptive control Patrice Antoinette and Gilles Ferreres for implementing the LFT controller is reduced. This controller is scheduled as a function of the parameters) and of gain- scheduled control (LPV methods) has been (much) less investigated, see for instance [10], [11

471

Optical gain from the direct gap transition of Ge-on-Si at room temperature  

E-Print Network [OSTI]

We report direct band gap optical gain of tensile strained n+ epitaxial Ge-on-Si at room temperature, which confirms that band-engineered Ge-on-Si is a promising gain medium for monolithic optical amplifiers and lasers on Si.

Liu, Jifeng

472

Gain-scheduled `1 -optimal control for boiler-turbine dynamics  

E-Print Network [OSTI]

, into the mechanical energy acting on the turbine and generator. The steam generated in the boiler system servesGain-scheduled `1 -optimal control for boiler-turbine dynamics with actuator saturation Pang; accepted 2 June 2003 Abstract This paper presents a gain-scheduled approach for boiler-turbine controller

Shamma, Jeff S.

473

Collective friction coefficients in the relaxation time approximation F. A. Ivanyuk  

E-Print Network [OSTI]

Collective friction coefficients in the relaxation time approximation F. A. Ivanyuk Institute components of the friction coefficient for various single-particle potentials and have found that the nondiagonal component of the friction coefficient depends generally on the diffuseness of the potential

Pomorski, Krzysztof

474

Heat driven heat pump using paired ammoniated salts  

SciTech Connect (OSTI)

A cycle for a heat driven heat pump using two salts CaCl/sup 2/.8NH/sup 3/, and ZnCl/sup 2/.4NH3 which may reversibly react with ammonia with the addition or evolution of heat. These salts were chosen so that both ammoniation processes occur at the same temperature so that the heat evolved may be used for comfort heating. The heat to drive the system need only be slightly hotter than 122 C. The low temperature source need only be slightly warmer than 0 C.

Dunlap, R.M.

1980-08-29T23:59:59.000Z

475

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

E-Print Network [OSTI]

-reaching meaning of solving energy and environment problems if new type energy conservation and environment protection heating system ? solar assisted ground-source heat pump (SAGHP) heating system with a latent heat storage tank will be practical... was established at the laboratory of construction energy conservation in Harbin Institute of Technology (HIT) in 2004. It added a latent heat storage tank in original SAGHP system. The schematic diagram of the system is shown in Figure 1. The experimental...

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

2006-01-01T23:59:59.000Z

476

Wastewater heat recovery apparatus  

DOE Patents [OSTI]

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

Kronberg, J.W.

1992-09-01T23:59:59.000Z

477

Wastewater heat recovery apparatus  

DOE Patents [OSTI]

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

Kronberg, James W. (108 Independent Blvd., Aiken, SC 29801)

1992-01-01T23:59:59.000Z

478

Low Level Heat Recovery Through Heat Pumps and Vapor Recompression  

E-Print Network [OSTI]

The intent of this paper is to examine the methods and economics of recovering low level heat through heat pumps and vapor recompression. Actual commercially available equipment is considered to determine the near-term and future economic viability...

Gilbert, J.

1980-01-01T23:59:59.000Z

479

TRANSPARENT HEAT MIRRORS FOR PASSIVE SOLAR HEATING APPLICATIONS  

E-Print Network [OSTI]

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

Selkowitz, S.

2011-01-01T23:59:59.000Z

480

Heat Transfer Derivation of differential equations for heat transfer conduction  

E-Print Network [OSTI]

) or kW *h or Btu. U is the change in stored energy, in units of kW *h (kWh) or Btu. qx is the heat conducted (heat flux) into the control volume at surface edge x, in units of kW/m2 or Btu/(h-ft2). qx volume is positive), in kW/m3 or Btu/(h-ft3) (a heat sink, heat drawn out of the volume, is negative

Veress, Alexander

Note: This page contains sample records for the topic "heat gain coefficient" 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

SOLAR MAGNETIC FIELD SIGNATURES IN HELIOSEISMIC SPLITTING COEFFICIENTS  

SciTech Connect (OSTI)

Normal modes of oscillation of the Sun are useful probes of the solar interior. In this work, we use the even-order splitting coefficients to study the evolution of magnetic fields in the convection zone over solar cycle 23, assuming that the frequency splitting is only due to rotation and a large-scale magnetic field. We find that the data are best fit by a combination of a poloidal field and a double-peaked near-surface toroidal field. The toroidal fields are centered at r {sub 0} = 0.999 R {sub sun} and r = 0.996 R {sub sun} and are confined to the near-surface layers. The poloidal field is a dipole field. The peak strength of the poloidal field is 124 +- 17 G. The toroidal field peaks at 380 +- 30 G and 1.4 +- 0.2 kG for the shallower and deeper fields, respectively. The field strengths are highly correlated with surface activity. The toroidal field strength shows a hysteresis-like effect when compared to the global 10.7 cm radio flux. The poloidal field strength shows evidence of saturation at high activity.

Baldner, Charles S.; Basu, Sarbani [Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT, 06520-8101 (United States); Antia, H. M. [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India); Larson, Timothy P., E-mail: charles.baldner@yale.ed [Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305-4085 (United States)

2009-11-10T23:59:59.000Z

482

Diffusion coefficient and radial gradient of galactic cosmic rays  

E-Print Network [OSTI]

We present the temporal changes of the diffusion coefficient K of galactic cosmic rays (GCRs) at the Earth orbit calculated based on the experimental data using two different methods. The first approach is based on the Parker convection-diffusion approximation of GCR modulation [1]: i.e. K~Vr=dI where dI is the variation of the GCR intensity measured by neutron monitors (NM),V is the solar wind velocity and r is the radial distance. The second approach is based on the interplanetary magnetic field (IMF) data. It was suggested that parallel mean free path can be expressed in terms of B as in [2]-[4]. Using data of the product of the parallel mean free path and radial gradient of GCR calculated based on the GCR anisotropy data (Ahluwalia et al., this conference ICRC 2013, poster ID: 487 [5]), we estimate the temporal changes of the radial gradient of GCR at the Earth orbit. We show that the radial gradient exhibits a strong solar cycle dependence (11-year variation) and a weak solar magnetic cycle dependence (2...

Modzelewska, Renata

2015-01-01T23:59:59.000Z

483

Heat engine Device that transforms heat into work.  

E-Print Network [OSTI]

, and rocket engines are heat engines. So are steam engines and turbines #12;2 refrigerator Device that uses by steam turbines. Steam turbines, jet engines and rocket engines use a Brayton cycle #12;4 Steam turbines1 Heat engine Device that transforms heat into work. It requires two energy reservoirs at different

Winokur, Michael

484

Fast reactor power plant design having heat pipe heat exchanger  

DOE Patents [OSTI]

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

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

1984-08-30T23:59:59.000Z

485

Fast reactor power plant design having heat pipe heat exchanger  

DOE Patents [OSTI]

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

Huebotter, Paul R. (Western Springs, IL); McLennan, George A. (Downers Grove, IL)

1985-01-01T23:59:59.000Z

486

Analysis of gain margins and phase margins of a nonlinear reactor control system  

SciTech Connect (OSTI)

By using the gain-phase margin tester, the parameter-plane method for the nonlinear control system is extended to frequency-domain related to gain margin and phase margin. The stability and self-excited oscillation are investigated with respect to the adjustable parameters. The useful information concerning the effect of adjustable parameters can be obtained, after the describing function curves and the boundaries of constant gain margin and constant phase margin are plotted in the parameter plane. Some interesting consequences are offered by employing the practical control system of a material testing reactor.

Chang, C.H.; Chang, M.K. (Chung Cheng Inst. of Technology, Tao-Yuan (Taiwan, Province of China))

1994-08-01T23:59:59.000Z

487

Calibration of photomultipliers gain used in the J-PET detector  

E-Print Network [OSTI]

Photomultipliers are commonly used in commercial PET scanner as devices which convert light produced in scintillator by gamma quanta from positron-electron annihilation into electrical signal. For proper analysis of obtained electrical signal, a photomultiplier gain curve must be known, since gain can be significantly different even between photomultipliers of the same model. In this article we describe single photoelectron method used for photomultipliers calibration applied for J-PET scanner, a novel PET detector being developed at the Jagiellonian University. Description of calibration method, an example of calibration curve and gain of few R4998 Hamamatsu photomultipliers are presented.

Bednarski, T; Moskal, P; Bia?as, P; Giergiel, K; Kap?on, ?; Kochanowski, A; Korcyl, G; Kowal, J; Kowalski, P; Kozik, T; Krzemie?, W; Molenda, M; Moskal, I; Nied?wiecki, Sz; Pa?ka, M; Pawlik, M; Raczy?ski, L; Rudy, Z; Salabura, P; Sharma, N G; Silarski, M; S?omski, A; Smyrski, J; Strzelecki, A; Szyma?ski, K; Wi?licki, W; Witkowski, P; Zieli?ski, M; Zo?, N

2013-01-01T23:59:59.000Z

488

Negative differential gain in quantum dot systems: Interplay of structural properties and many-body effects  

SciTech Connect (OSTI)

The saturation behaviour of optical gain with increasing excitation density is an important factor for laser device performance. For active materials based on self-organized InGaAs/GaAs quantum dots, we study the interplay between structural properties of the quantum dots and many-body effects of excited carriers in the optical properties via a combination of tight-binding and quantum-kinetic calculations. We identify regimes where either phase-space filling or excitation-induced dephasing dominates the saturation behavior of the optical gain. The latter can lead to the emergence of a negative differential material gain.

Goldmann, E., E-mail: goldmann@itp.uni-bremen.de; Jahnke, F. [Institute for Theoretical Physics, University of Bremen, Bremen 28359 (Germany); Lorke, M.; Frauenheim, T. [Bremen Center for Computational Materials Science BCCMS, University of Bremen, Bremen 28359 (Germany)

2014-06-16T23:59:59.000Z

489

Heat Transfer Boundary Conditions in the RELAP5-3D Code  

SciTech Connect (OSTI)

The heat transfer boundary conditions used in the RELAP5-3D computer program have evolved over the years. Currently, RELAP5-3D has the following options for the heat transfer boundary conditions: (a) heat transfer correlation package option, (b) non-convective option (from radiation/conduction enclosure model or symmetry/insulated conditions), and (c) other options (setting the surface temperature to a volume fraction averaged fluid temperature of the boundary volume, obtaining the surface temperature from a control variable, obtaining the surface temperature from a time-dependent general table, obtaining the heat flux from a time-dependent general table, or obtaining heat transfer coefficients from either a time- or temperature-dependent general table). These options will be discussed, including the more recent ones.

Richard A. Riemke; Cliff B. Davis; Richard R. Schultz

2008-05-01T23:59:59.000Z

490

Combined heat and mass transfer device for improving separation process  

DOE Patents [OSTI]

A two-phase small channel heat exchange matrix simultaneously provides for heat transfer and mass transfer between the liquid and vapor phases of a multi-component mixture at a single, predetermined location within a separation column, significantly improving the thermodynamic efficiency of the separation process. The small channel heat exchange matrix is composed of a series of channels having a hydraulic diameter no greater than 5.0 millimeters for conducting a two-phase coolant. In operation, the matrix provides the liquid-vapor contacting surfaces within the separation column, such that heat and mass are transferred simultaneously between the liquid and vapor phases. The two-phase coolant allows for a uniform heat transfer coefficient to be maintained along the length of the channels and across the surface of the matrix. Preferably, a perforated, concave sheet connects each channel to an adjacent channel to facilitate the flow of the liquid and vapor phases within the column and to increase the liquid-vapor contacting surface area.

Tran, Thanh Nhon (Flossmoor, IL)

1999-01-01T23:59:59.000Z

491

Combined heat and mass transfer device for improving separation process  

DOE Patents [OSTI]

A two-phase small channel heat exchange matrix simultaneously provides for heat transfer and mass transfer between the liquid and vapor phases of a multi-component mixture at a single, predetermined location within a separation column, significantly improving the thermodynamic efficiency of the separation process. The small channel heat exchange matrix is composed of a series of channels having a hydraulic diameter no greater than 5.0 millimeters for conducting a two-phase coolant. In operation, the matrix provides the liquid-vapor contacting surfaces within the separation column, such that heat and mass are transferred simultaneously between the liquid and vapor phases. The two-phase coolant allows for a uniform heat transfer coefficient to be maintained along the length of the channels and across the surface of the matrix. Preferably, a perforated, concave sheet connects each channel to an adjacent channel to facilitate the flow of the liquid and vapor phases within the column and to increase the liquid-vapor contacting surface area. 12 figs.

Tran, T.N.

1999-08-24T23:59:59.000Z

492

Heat transport measurements in turbulent rotating Rayleigh-Benard convection  

SciTech Connect (OSTI)

We present experimental heat transport measurements of turbulent Rayleigh-Benard convection with rotation about a vertical axis. The fluid, water with Prandtl number ({sigma}) about 6, was confined in a cell which had a square cross section of 7.3 cm x 7.3 cm and a height of 9.4 cm. Heat transport was measured for Rayleigh numbers 2 x 10{sup 5} < Ra < 5 x 10{sup 8} and Taylor numbers 0 < Ta < 5 x 10{sup 9}. We show the variation of normalized heat transport, the Nusselt number, at fixed dimensional rotation rate {Omega}{sub D}, at fixed Ra varying Ta, at fixed Ta varying Ra, and at fixed Rossby number Ro. The scaling of heat transport in the range 10{sup 7} to about 10{sup 9} is roughly 0.29 with a Ro dependent coefficient or equivalently is also well fit by a combination of power laws of the form a Ra{sup 1/5} + b Ra{sup 1/3} . The range of Ra is not sufficient to differentiate single power law or combined power law scaling. The overall impact of rotation on heat transport in turbulent convection is assessed.

Ecke, Robert E [Los Alamos National Laboratory; Liu, Yuanming [Los Alamos National Laboratory

2008-01-01T23:59:59.000Z

493

DIRECT MEASUREMENT OF HEAT FLUX FROM COOLING LAKE THERMAL IMAGERY  

SciTech Connect (OSTI)

Laboratory experiments show a linear relationship between the total heat flux from a water surface to air and the standard deviation of the surface temperature field, {sigma}, derived from thermal images of the water surface over a range of heat fluxes from 400 to 1800 Wm{sup -2}. Thermal imagery and surface data were collected at two power plant cooling lakes to determine if the laboratory relationship between heat flux and {sigma} exists in large heated bodies of water. The heat fluxes computed from the cooling lake data range from 200 to 1400 Wm{sup -2}. The linear relationship between {sigma} and Q is evident in the cooling lake data, but it is necessary to apply band pass filtering to the thermal imagery to remove camera artifacts and non-convective thermal gradients. The correlation between {sigma} and Q is improved if a correction to the measured {sigma} is made that accounts for wind speed effects on the thermal convection. Based on more than a thousand cooling lake images, the correlation coefficients between {sigma} and Q ranged from about 0.8 to 0.9.

Garrett, A; Eliel Villa-Aleman, E; Robert Kurzeja, R; Malcolm Pendergast, M; Timothy Brown, T; Saleem Salaymeh, S

2007-12-19T23:59:59.000Z

494

Downstream Heat Flux Profile vs. Midplane T Profile in Tokamaks  

SciTech Connect (OSTI)

The relationship between the midplane scrape-off-layer electron temperature profile and the parallel heat flux profile at the divertor in tokamaks is investigated. A model is applied which takes into account anisotropic thermal diffusion, in a rectilinear geometry with constant density. Eigenmode analysis is applied to the simplified problem with constant thermal diffusivities. A self-similar nonlinear solution is found for the more realistic problem with anisotropically temperature-dependent thermal diffusivities. Numerical solutions are developed for both cases, with spatially dependent heat flux emerging from the plasma. For both constant and temperature-dependent thermal diffusivities it is found that, below about one-half of its peak, the heat flux profile shape at the divertor, compared with the midplane temperature profile shape, is robustly described by the simplest two-point model. However the physical processes are not those assumed in the simplest two-point model, nor is the numerical coefficient relating q||div to Tmp ?||mp/L|| as predicted. For realistic parameters the peak in the heat flux, moreover, can be reduced by a factor of two or more from the two-point model scaling which fits the remaining profile. For temperature profiles in the SOL region above the x-point set by marginal stability, the heat flux profile to the divertor can be largely decoupled from the prediction of the two-point model. These results suggest caveats for data interpretation, and possibly favorable outcomes for divertor configurations with extended field lines.

Robert J. Goldston

2009-08-20T23:59:59.000Z

495

Geothermal Heat Pump Grant Program  

Broader source: Energy.gov [DOE]

The Maryland Energy Administration (MEA) offers rebates of $3,000 for residential geothermal heat pump systems and up to $4,500 for non-residential geothermal heat pump systems. The residential...

496

Heat Pipes: An Industrial Application  

E-Print Network [OSTI]

This paper reviews the basics of heat pipe exchangers. Included are how they are constructed, how they operate, where they have application, and various aspects of evaluating a potential application. After discussing the technical aspects of heat...

Murray, F.

1984-01-01T23:59:59.000Z

497

Challenges in Industrial Heat Recovery  

E-Print Network [OSTI]

This presentation will address several completed and working projects involving waste heat recovery in a chemical plant. Specific examples will be shown and some of the challenges to successful implementation and operation of heat recovery projects...

Dafft, T.

2007-01-01T23:59:59.000Z

498

Heat Pumps - Theory and Applications  

E-Print Network [OSTI]

compressors (heat pumps) with actual applications in Monsanto. Guidelines for possible application areas are drawn from the analysis, and conclusions are drawn both about the usefulness of exergy analysis and about the heat pump application areas....

Altin, M.

1982-01-01T23:59:59.000Z

499

Faculty Positions Heat Transfer and  

E-Print Network [OSTI]

Faculty Positions Heat Transfer and Thermal/Energy Sciences Naval Postgraduate School Monterey-track faculty position at the assistant professor level in the areas of Heat Transfer and Thermal/Fluid Sciences

500

Residential Solar Water Heating Rebates  

Broader source: Energy.gov [DOE]

New Hampshire offers a rebate for residential solar water-heating systems and solar space-heating systems. The rebate is equal to $1,500 for systems with an annual estimated output of 5.5 MMBTU to...