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Note: This page contains sample records for the topic "operating heat rate" from the National Library of EnergyBeta (NLEBeta).
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1

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

E-Print Network (OSTI)

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

2

ARM - Measurement - Radiative heating rate  

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

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

3

Heat Transfer Operators Associated with Quantum Operations  

E-Print Network (OSTI)

Any quantum operation applied on a physical system is performed as a unitary transformation on a larger extended system. If the extension used is a heat bath in thermal equilibrium, the concomitant change in the state of the bath necessarily implies a heat exchange with it. The dependence of the average heat transferred to the bath on the initial state of the system can then be found from the expectation value of a hermitian operator, which is named as the heat transfer operator (HTO). The purpose of this article is the investigation of the relation between the HTOs and the associated quantum operations. Since, any given quantum operation on a system can be realized by different baths and unitaries, many different HTOs are possible for each quantum operation. On the other hand, there are also strong restrictions on the HTOs which arise from the unitarity of the transformations. The most important of these is the Landauer erasure principle. This article is concerned with the question of finding a complete set of restrictions on the HTOs that are associated with a given quantum operation. An answer to this question has been found only for a subset of quantum operations. For erasure operations, these characterizations are equivalent to the generalized Landauer erasure principle. For the case of generic quantum operations however, it appears that the HTOs obey further restrictions which cannot be obtained from the entropic restrictions of the generalized Landauer erasure principle.

. Aksak; S. Turgut

2011-04-14T23:59:59.000Z

4

Combined Retrieval, Microphysical Retrievals and Heating Rates  

DOE Data Explorer (OSTI)

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

Feng, Zhe

5

Heating Rate Profiles in Galaxy Clusters  

E-Print Network (OSTI)

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

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

2006-01-05T23:59:59.000Z

6

Property:HeatRate | Open Energy Information  

Open Energy Info (EERE)

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

7

Heat kernel asymptotics for magnetic Schrdinger operators  

SciTech Connect

We explicitly construct parametrices for magnetic Schrdinger operators on R{sup d} and prove that they provide a complete small-t expansion for the corresponding heat kernel, both on and off the diagonal.

Bolte, Jens, E-mail: jens.bolte@rhul.ac.uk [Department of Mathematics, Royal Holloway, University of London, Egham TW20 0EX (United Kingdom)] [Department of Mathematics, Royal Holloway, University of London, Egham TW20 0EX (United Kingdom); Keppeler, Stefan, E-mail: stefan.keppeler@uni-tuebingen.de [Mathematisches Institut, Universitt Tbingen, Auf der Morgenstelle 10, 72076 Tbingen (Germany)] [Mathematisches Institut, Universitt Tbingen, Auf der Morgenstelle 10, 72076 Tbingen (Germany)

2013-11-15T23:59:59.000Z

8

Standby Rates for Combined Heat and Power Systems  

SciTech Connect

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

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

2014-02-01T23:59:59.000Z

9

Renewable Combined Heat and Power Dairy Operations  

E-Print Network (OSTI)

horsepower Guascor model SFGLD-560 biogas-fired lean burn internal combustion (IC) engine and generator set and modify the existing biogas toelectricity combined heat and power (CHP) system operated at Fiscalini bacteria to remove hydrogen sulfide presented in the biogas. Source: Fiscalini Farms Term: March 2011

10

Operating and Maintaining Your Heat Pump | Department of Energy  

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

Operating and Maintaining Your Heat Pump Operating and Maintaining Your Heat Pump Operating and Maintaining Your Heat Pump June 24, 2012 - 3:22pm Addthis Changing filters regularly is an important part of maintaining a heat pump system. | Photo courtesy of ©iStockphoto/BanksPhotos Changing filters regularly is an important part of maintaining a heat pump system. | Photo courtesy of ©iStockphoto/BanksPhotos What does this mean for me? Learn to operate and maintain your heat pump system properly to maximize energy and money savings. You can do many operational and maintenance tasks yourself. Proper operation of your heat pump will save energy. Do not set back the heat pump's thermostat if it causes the backup heating to come on -- backup heating systems are usually more expensive to operate. Continuous indoor

11

TEMPERED OPERATORS AND THE HEAT KERNEL AND COMPLEX POWERS OF ELLIPTIC PSEUDODIFFERENTIAL OPERATORS  

E-Print Network (OSTI)

TEMPERED OPERATORS AND THE HEAT KERNEL AND COMPLEX POWERS OF ELLIPTIC PSEUDODIFFERENTIAL OPERATORS operator and complex powers of b-pseudodi#27;erential operators, as the heat operator and complex powers are the Laplace and Mellin transforms, respectively, of the resolvent. The heat operator and complex powers

Loya, Paul

12

Fabrication and heating rate study of microscopic surface electrode ion traps  

E-Print Network (OSTI)

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

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

2010-09-15T23:59:59.000Z

13

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

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

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

14

Method of calculation of heat generation rates for DWPF glass  

SciTech Connect

The Waste Acceptance Preliminary Specifications (WAPS) require estimates of the heat generation rate of DWPF waste glasses. Estimates of the heat generation rates of projected glass compositions are to be reported in the Waste Form Qualification Report. Similar estimates for actual production glasses are to be reported in the Production Records. In this report, a method of calculating the heat generation rate from the radionuclide inventory is provided. Application of the method to the DWPF Design-Basis glass indicates that the heat generation rate can be accurately estimated from the Sr-90, Y-90, Cs-137, Ba-137m, and Pu-238 contents alone.

Plodinec, M.J.

1992-03-17T23:59:59.000Z

15

Method of calculation of heat generation rates for DWPF glass  

SciTech Connect

The Waste Acceptance Preliminary Specifications (WAPS) require estimates of the heat generation rate of DWPF waste glasses. Estimates of the heat generation rates of projected glass compositions are to be reported in the Waste Form Qualification Report. Similar estimates for actual production glasses are to be reported in the Production Records. In this report, a method of calculating the heat generation rate from the radionuclide inventory is provided. Application of the method to the DWPF Design-Basis glass indicates that the heat generation rate can be accurately estimated from the Sr-90, Y-90, Cs-137, Ba-137m, and Pu-238 contents alone.

Plodinec, M.J.

1993-02-04T23:59:59.000Z

16

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

17

Hot Water Heating System Operation and Energy Conservation  

E-Print Network (OSTI)

Based on an example of the reconstruction of a hot water heating system, this paper provides an analysis and comparison of the operations of hot water heating systems, including supply water temperature adjustment, flow adjustment during each...

Shao, Z.; Chen, H.; Wei, P.

2006-01-01T23:59:59.000Z

18

Optimization of the Heating System Operation  

E-Print Network (OSTI)

on the basis of the variation of outdoor temperature, and in this way, the heating system can be optimized....

Xu, W.; Mao, S.

2006-01-01T23:59:59.000Z

19

Tables for solution of the heat-conduction equation with a time-dependent heating rate  

E-Print Network (OSTI)

Tables are presented for the solution of the transient onedimensional heat flow in a solid body of constant material properties with the heating rate at one boundary dependent on time. These tables allow convenient and ...

Bergles A. E.

1962-01-01T23:59:59.000Z

20

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.

Note: This page contains sample records for the topic "operating heat rate" 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

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

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

ProductsBroadband Heating Rate Profile Project ProductsBroadband Heating Rate Profile Project (BBHRP) Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : Broadband Heating Rate Profile Project (BBHRP) 2000.03.01 - 2006.02.28 Site(s) SGP General Description The objective of the ARM Broadband Heating Rate Profile (BBHRP) Project is to provide a structure for the comprehensive assessment of our ability to model atmospheric radiative transfer for all conditions. Required inputs to BBHRP include surface albedo and profiles of atmospheric state (temperature, humidity), gas concentrations, aerosol properties, and cloud properties. In the past year, the Radiatively Important Parameters Best Estimate (RIPBE) VAP was developed to combine all of the input properties

22

Solar Heating Rates: The Importance of Spherical Geometry  

Science Journals Connector (OSTI)

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

D. J. Lary; M. Balluch

1993-12-01T23:59:59.000Z

23

Project Profile: High Operating Temperature Liquid Metal Heat...  

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

investigating the use of metal alloys as a heat transfer fluid (HTF) in concentrating solar power (CSP) systems operating at temperatures in excess of 800C. By allowing higher...

24

Inverse bremsstrahlung heating rate for dense plasmas in laser fields  

SciTech Connect

We report a theoretical analysis of inverse bremsstrahlung heating rate in the eikonal approximation. The present analysis is performed for a dense plasma using the screened electron-ion interaction potential for the ion charge state Z{sub i} = 1 and for both the weak and strong plasma screening cases. We have also compared the eikonal results with the first Born approximation (FBA) [M. Moll et al., New J. Phys. 14, 065010 (2012)] calculation. We find that the magnitudes of inverse bremsstrahlung heating rate within the eikonal approximation (EA) are larger than the FBA values in the weak screening case (? = 0.03 a.u.) in a wide range of field strength for three different initial electron momenta (2, 3, and 4 a.u.). But for strong screening case (? = 0.3 a.u.), the heating rates predicted by the two approximations do not differ much after reaching their maximum values. Furthermore, the individual contribution of photoemission and photoabsorption processes to heating rate is analysed for both the weak and strong screening cases. We find that the single photoemission and photoabsorption rates are the same throughout the field strength while the multiphoton absorption process dominates over the multiphoton emission process beyond the field strength ? 410{sup 8} V/cm. The present study of the dependence of heating rate on the screening parameter ranging from 0.01 to 20 shows that whereas the heating rate predicted by the EA is greater than the FBA up to the screening parameter ? = 0.3 a.u., the two approximation methods yield results which are nearly identical beyond the above value.

Dey, R. [D-203, Samruddhi Residency, Motera, Ahmedabad-380009, Gujarat (India)] [D-203, Samruddhi Residency, Motera, Ahmedabad-380009, Gujarat (India); Roy, A. C. [School of Mathematical Sciences, Ramakrishna Mission Vivekananda University, Belur Math 711202, West Bengal (India)] [School of Mathematical Sciences, Ramakrishna Mission Vivekananda University, Belur Math 711202, West Bengal (India)

2013-07-15T23:59:59.000Z

25

Experimental performance analysis of a solar assisted ground source heat pump system under different heating operation modes  

Science Journals Connector (OSTI)

Abstract This paper presents an experimental study on the influence of operation modes on the heating performance of a solar assisted ground source heat pump system (SAGSHPS). Through experiments conducted in January, the characteristics of the SAGSHPS were investigated under different heating operation modes. The results indicate that the solar thermal could be used to accelerate the soil recovery when the heat pump unit is turned off, but the duration of solar use to recharge boreholes should be optimized according to the water temperature in the solar heat storage water tank to avoid unnecessary power consumption of the circulation pump. In addition, the solar heat storage water tank is beneficial for the stable operation of the SAGSHPS. The volumetric flow rate in the water tank has a significant impact on the electricity consumption of the SAGSHPS. From comprehensive analysis of the integral effect of the SAGSHPS under different modes, the mode in which the water tank is connected with the ground heat exchangers (GHES) in series is the recommended mode for the SAGSHPS in the coldest month in Dalian.

Lanhua Dai; Sufen Li; Lin DuanMu; Xiangli Li; Yan Shang; Ming Dong

2015-01-01T23:59:59.000Z

26

Generalized constructal optimization for solidification heat transfer process of slab continuous casting based on heat loss rate  

Science Journals Connector (OSTI)

Abstract Based on constructal theory, generalized constructal optimization of a solidification heat transfer process of slab continuous casting is carried out by taking a complex function as optimization objective. The complex function is composed of the functions of the heat loss rate and surface temperature gradient of the slab subjected to the constraints of shell thickness, surface temperature and liquid core length of the slab. For the specified total water flow rate, the optimal construct of the water distribution in the secondary cooling zone is obtained. Comparing the optimal results with the initial ones, it is shown that the complex function, the functions of the heat loss rate and the surface temperature gradient after optimization are decreased by 35.04%, 2.14% and 59.48%, respectively. Therefore, the scheme of the optimal construct of the water distribution reduces the heat loss rate and surface temperature gradient of the slab simultaneously, that is, improves its energy retention and quality simultaneously. The optimization results obtained in this paper can provide some guidelines for parameter designs and dynamic operations of the solidification heat transfer process of slab continuous casting.

Huijun Feng; Lingen Chen; Zhihui Xie; Zemin Ding; Fengrui Sun

2014-01-01T23:59:59.000Z

27

Status of the Broadband Heating Rate Profile (BBHRP) VAP  

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

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

28

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

E-Print Network (OSTI)

An on-line expert system for fossil-fueled power plants, the "Heat Rate Degradation Expert System Advisor," is being developed. This expert system will operate on a microcomputer and will interface with existing plant data acquisition and/or thermal...

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

29

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

E-Print Network (OSTI)

Particle loading rates for HVAC filters, heat exchangers, and ducts Nomenclature Afl surface area of floor (m2 ) bf fraction of bypass flow around the filter (dimensionless) Cout outdoor concentration on the filter per volume of air (mg/lm m3 ) Mf,tot total mass deposited on the filter per month of operation (g

Siegel, Jeffrey

30

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

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

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

31

Prediction of the heat release rate of wood  

SciTech Connect

A model for the heat release rate of wood during flaming combustion was developed during this research. It includes the effects of char shrinkage, multiple chemical components, adsorbed moisture, internal convective cooling and the variation of the thermophysical and thermochemical properties with temperature and the mass retention fraction of the char. It does not include char oxidation or diffusion of moisture and volatile pyrolysis products toward the rear surface. It calculates the time to ignition, mass burning rate, heat release rate, heat of combustion, heat of gasification and depth of char. An important part of this research was the determination of the thermochemical and thermophysical properties required by the model. An apparatus was developed for determining the kinetic parameters and the heat of combustion of the volatiles under conditions similar to those in the interior of a flaming slab of wood. Data were obtained on each of the four major chemical components present in Douglas fir. Thermal diffusivity measurements on Douglas fir and its char yielded an average value of 2.1 {times} 10{sup {minus}7} s{sup 2}/s which was nearly independent of temperature and mass retention fraction of the char for temperature sup to 500{degree}C and for mass-retention fractions above 0.30.

Parker, W.J.

1988-01-01T23:59:59.000Z

32

Sensitivity of Radiative Fluxes and Heating Rates to Cloud Microphysics  

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

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

33

Project Profile: High Operating Temperature Liquid Metal Heat Transfer Fluids  

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

The University of California, Los Angeles (UCLA), along with partners at the University of California, Berkeley, and Yale University, under the 2012 Multidisciplinary University Research Initiative (MURI): High Operating Temperature (HOT) Fluids funding opportunity, is investigating the use of metal alloys as a heat transfer fluid (HTF) in concentrating solar power (CSP) systems operating at temperatures in excess of 800C. By allowing higher temperature operation, CSP systems can achieve greater efficiencies and thereby reduce the overall cost of electricity production.

34

Gas temperature profiles at different flow rates and heating rates suffice to estimate kinetic parameters for fluidised bed combustion  

SciTech Connect

Experimental work on estimation kinetic parameters for combustion was conducted in a bench-scale fluidised bed (FB: 105x200mm). Combustion medium was obtained by using an electrical heater immersed into the bed. The ratio of heating rate (kJ/s) to molar flow rate of air (mol/s) regulated by a rheostat so that the heat of combustion (kJ/mol) can be synthetically obtained by an electrical power supply for relevant O{sub 2}-feedstock concentration (C{sub 0}). O{sub 2}-restriction ratio ({beta}) was defined by the ratio of O{sub 2}-feedstock concentration to O{sub 2}-air concentration (C{sub O{sub 2}-AIR}) at prevailing heating rates. Compressed air at further atmospheric pressure ({approx_equal}102.7kPa) entered the bed that was alumina particles (250{mu}m). Experiments were carried out at different gas flow rates and heating rates. FB was operated with a single charge of (1300g) particles for obtaining the T/T{sub 0} curves, and than C/C{sub 0} curves. The mathematical relationships between temperature (T) and conversion ratio (X) were expressed by combining total energy balance and mass balance in FB. Observed surface reaction rate constants (k{sub S}) was obtained from the combined balances and proposed model was also tested for these kinetic parameters (frequency factor: k{sub 0}, activation energy: E{sub A}, and reaction order: n) obtained from air temperature measurements. It was found that the model curves allow a good description of the experimental data. Thus, reaction rate for combustion was sufficiently expressed. (author)

Suyadal, Y. [Faculty of Engineering, Department of Chemical Engineering, Ankara University, 06100-Tandogan, Ankara (Turkey)

2006-07-15T23:59:59.000Z

35

Cloud Properties and Radiative Heating Rates for TWP  

DOE Data Explorer (OSTI)

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

Comstock, Jennifer

36

Cloud Properties and Radiative Heating Rates for TWP  

SciTech Connect

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

Comstock, Jennifer

2013-11-07T23:59:59.000Z

37

E-Print Network 3.0 - as-operated heat loss Sample Search Results  

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

operated heat loss Search Powered by Explorit Topic List Advanced Search Sample search results for: as-operated heat loss Page: << < 1 2 3 4 5 > >> 1 Factsheet on Summer Heat Gain...

38

Property:Heat Recovery Rating | Open Energy Information  

Open Energy Info (EERE)

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

39

The nuclear heated steam reformer Design and semitechnical operating experiences  

Science Journals Connector (OSTI)

Good operating experiences of the EVA I- and EVA II-plant have been described. Therin the comparison of the different catalyst concepts has been given. Further the behaviour of the bundle of EVA II plant by isolation of individual reformer tubes as well as the performance of the bundle under transient conditions have been explained. Different design concepts for a nuclear heated steam reformer based on the concentric tubes and baffles have been given. Main points of studies are constructional details, thermohydraulic of the bundle and stress analysis. It can be shown that the present standard of knowledge allows the application of the steam reformer for coal refinement with nuclear heat.

J. Singh; H.F. Niessen; R. Harth; H. Fedders; H. Reutler; W. Panknin; W.D. Mller; H.G. Harms

1984-01-01T23:59:59.000Z

40

High Operating Temperature Liquid Metal Heat Transfer Fluids  

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

This fact sheet describes a UCLA-led solar project to investigate high operating temperature liquid metal heat transfer fluids, funded by the SunShot initiative. The project team is using a combination of modeling along with a variety of property measurement and validation studies to demonstrate that the metal alloys identified can meet all the needs of a concentrating solar power plant. A successful candidate fluid would allow for the reduction of the levelized cost of energy by increasing the operating temperature for the CSP plant power cycle, which would increase thermal-to-electric conversion efficiency.

Note: This page contains sample records for the topic "operating heat rate" 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

Broadband Heating Rate Profile Project (BBHRP) - SGP ripbe1mcfarlane  

SciTech Connect

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

Riihimaki, Laura; Shippert, Timothy

2014-11-05T23:59:59.000Z

42

Broadband Heating Rate Profile Project (BBHRP) - SGP ripbe370mcfarlane  

SciTech Connect

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

Riihimaki, Laura; Shippert, Timothy

2014-11-05T23:59:59.000Z

43

Broadband Heating Rate Profile Project (BBHRP) - SGP ripbe1mcfarlane  

DOE Data Explorer (OSTI)

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

Riihimaki, Laura; Shippert, Timothy

44

Broadband Heating Rate Profile Project (BBHRP) - SGP ripbe370mcfarlane  

DOE Data Explorer (OSTI)

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

Riihimaki, Laura; Shippert, Timothy

45

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

46

EAST ion cyclotron resonance heating system for long pulse operation  

Science Journals Connector (OSTI)

Abstract Radio frequency (RF) power in the ion cyclotron range of frequencies (ICRF) is one of the primary auxiliary heating techniques for Experimental Advanced Superconducting Tokamak (EAST). The ICRF system for EAST has been developed to support long-pulse high-? advanced tokamak fusion physics experiments. The ICRF system is capable of delivering 12MW 1000-s RF power to the plasma through two antennas. The phasing between current straps of the antennas can be adjusted to optimize the RF power spectrum. The main technical features of the ICRF system are described. Each of the 8 ICRF transmitters has been successfully tested to 1.5MW for a wide range of frequency (2570MHz) on a dummy load. Part of the ICRF system was in operation during the EAST 2012 spring experimental campaign and a maximum power of 800kW (at 27MHz) lasting for 30s has been coupled for long pulse H mode operation.

Y.P. Zhao; X.J. Zhang; Y.Z. Mao; S. Yuan; D.Y. Xue; X. Deng; L. Wang; S.Q. Ju; Y. Cheng; C.M. Qin; G. Chen; Y. Lin; J.G. Li; B.N. Wan; Y.T. Song; F. Braun; R. Kumazawa; S. Wukitch

2014-01-01T23:59:59.000Z

47

Thermal analysis of an innovative heat pump operated desalination plant  

SciTech Connect

Sea and brackish water desalination can contribute to solve the problem of fresh water shortage in many and regions of the world. Nowadays most of the installed desalination plants employ distillation processes, like Multistage Flash (MSF), Multi effect Distillation (MED) and Vapor Compression (VC). VC process is called Mechanical Vapor Compression (MVC) when it employs a mechanical compressor, while it is called Thermal Compression when it employs a steam-ejector compressor. In this paper a new distillation plant for the treatment of sea water for drinking water purposes is presented. The most innovative feature of this system is the use of a heat pump as part of the desalting unit. The use of the heat pump in the proposed system enables desalting water evaporation and steam condensation at the same temperature, unlike conventional VC desalting systems where a steam compression stage is necessary. A thermal analysis of the heat pump-operated desalination (HPD) plant and a comparison between the HPD and a conventional MVC plant is presented, in order to determine the main advantages and disadvantages of the new system.

Site, V.D. [National Research Council of Italy, Rome (Italy)

1995-12-31T23:59:59.000Z

48

Heat Kernel for Fractional Diffusion Operators with Perturbations  

E-Print Network (OSTI)

Let $L$ be an elliptic differential operator on a complete connected Riemannian manifold $M$ such that the associated heat kernel has two-sided Gaussian bounds as well as a Gaussian type gradient estimate. Let $L^{(\\aa)}$ be the $\\aa$-stable subordination of $L$ for $\\aa\\in (1,2).$ We found some classes $\\mathbb K_\\aa^{\\gg,\\bb} (\\bb,\\gg\\in [0,\\aa))$ of time-space functions containing the Kato class, such that for any measurable $b: [0,\\infty)\\times M\\to TM$ and $c: [0,\\infty)\\times M\\to M$ with $|b|, c\\in \\mathbb K_\\aa^{1,1},$ the operator $$L_{b,c}^{(\\aa)}(t,x):= L^{(\\aa)}(x)+ +c(t,x),\\ \\ (t,x)\\in [0,\\infty)\\times M$$ has a unique heat kernel $p_{b,c}^{(\\aa)}(t,x;s,y), 0\\le s1$, where $\\rr$ is the Riemannian distance. The estimate of $\

Feng-Yu Wang; Xicheng Zhang

2012-04-23T23:59:59.000Z

49

SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer  

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

High Operating Temperature Liquid High Operating Temperature Liquid Metal Heat Transfer Fluids to someone by E-mail Share SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer Fluids on Facebook Tweet about SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer Fluids on Twitter Bookmark SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer Fluids on Google Bookmark SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer Fluids on Delicious Rank SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer Fluids on Digg Find More places to share SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer Fluids on AddThis.com... Concentrating Solar Power Systems Components Competitive Awards

50

Measurements of Film Flow Rate in Heated Tubes with Various Axial Power Distributions  

E-Print Network (OSTI)

Measurements of Film Flow Rate in Heated Tubes with Various Axial Power Distributions by Carl, Measurements of Film Flow Rate in Heated Tubes with Various Axial Power Distributions KTH Nuclear Reactor power is limited by a phenomenon called critical heat flux (CHF). It appears as a sudden detoriation

Haviland, David

51

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

SciTech Connect

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

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

1996-05-01T23:59:59.000Z

52

IEA Heat Pump Conference 2011, 16 -19 May 2011, Tokyo, Japan ENERGY EFFICIENT AIR TO AIR HEAT PUMP OPERATING WITH  

E-Print Network (OSTI)

00149 -1- 10th IEA Heat Pump Conference 2011, 16 - 19 May 2011, Tokyo, Japan ENERGY EFFICIENT AIR TO AIR HEAT PUMP OPERATING WITH R-1234yf Sorina Mortada, Ph.D. student, Center for Energy and Processes Abstract: Significant improvements in energy performance of air-to-air heat pumps are the major reason

Paris-Sud XI, Université de

53

High rate heating driven decomposition of energetic materials: Diagnostics evaluation  

SciTech Connect

Combustion of energetic materials involves processes in both gas and condensed phases and is governed by coupled thermal, physical, and chemical phenomena. Development of reliable models for design, performance, stability, and hazard analyses requires detailed understanding of three general chemical reaction regimes: (1) initial condensed-phase decomposition, (2) subsequent interaction of decomposition products with the remaining condensed phase, and (3) gas-phase reaction of decomposition products to form the ultimate combustion products. The first two regimes are the least understood and most difficult to study, particularly the initial condensed-phase decomposition. The basic difficulty in studying condensed phase phenomena has been the inability to probe directly chemistry in the condensed phase under isothermal condition and with the spatial and temporal resolution needed at higher temperatures and reaction rates. Thin-film samples provide a means to study condensed-phase chemistry at isothermal conditions and with microsecond temporal resolution. We are developing an experiment system that employs rapidly heated thin- film samples and multiple diagnostics to examine condensed-phase chemistry and monitor evolved gas species. Results from our initial work have been encouraging. Thin-film samples of several energetic materials have been prepared and appear to be representative of bulk materials. Furthermore, preliminary experiments indicate that all the use of these samples with two chemical diagnostic techniques, time-of- flight mass spectrometry (TOFMS) and time-resolved infrared spectral photography (TRISP), is viable. 5 refs., 8 figs.

Trott, W.M.; Renlund, A.M.; Erickson, K.L.; Skocypec, R.D.

1991-01-01T23:59:59.000Z

54

High rate heating driven decomposition of energetic materials: Diagnostics evaluation  

SciTech Connect

Combustion of energetic materials involves processes in both gas and condensed phases and is governed by coupled thermal, physical, and chemical phenomena. Development of reliable models for design, performance, stability, and hazard analyses requires detailed understanding of three general chemical reaction regimes: (1) initial condensed-phase decomposition, (2) subsequent interaction of decomposition products with the remaining condensed phase, and (3) gas-phase reaction of decomposition products to form the ultimate combustion products. The first two regimes are the least understood and most difficult to study, particularly the initial condensed-phase decomposition. The basic difficulty in studying condensed phase phenomena has been the inability to probe directly chemistry in the condensed phase under isothermal condition and with the spatial and temporal resolution needed at higher temperatures and reaction rates. Thin-film samples provide a means to study condensed-phase chemistry at isothermal conditions and with microsecond temporal resolution. We are developing an experiment system that employs rapidly heated thin- film samples and multiple diagnostics to examine condensed-phase chemistry and monitor evolved gas species. Results from our initial work have been encouraging. Thin-film samples of several energetic materials have been prepared and appear to be representative of bulk materials. Furthermore, preliminary experiments indicate that all the use of these samples with two chemical diagnostic techniques, time-of- flight mass spectrometry (TOFMS) and time-resolved infrared spectral photography (TRISP), is viable. 5 refs., 8 figs.

Trott, W.M.; Renlund, A.M.; Erickson, K.L.; Skocypec, R.D.

1991-12-01T23:59:59.000Z

55

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

56

Methods for providing heat to electric operated LNG plant.  

E-Print Network (OSTI)

??Hammerfest LNG plant, located at Melkya outside Hammerfest, is supplied with heat and power from an on-site combined heat and power (CHP-) plant. This natural (more)

Tangs, Cecilie Magrethe

2010-01-01T23:59:59.000Z

57

Heat resistance and outgrowth of clostridium perfringens spores as affected by the type of heating medium, and heating and cooling rates in ground pork  

E-Print Network (OSTI)

) and cured ground pork (CGP) at 75C. The effect of the heating rate on HR, germination and outgrowth of C. perfringens spores in CGP was determined by increasing the temperature from 20 to 75C at a rate of 4, 8, and 12C/h prior to heating and holding at 75...

Marquez Gonzalez, Mayra

2009-05-15T23:59:59.000Z

58

Method of calculation of heat generation rates for DWPF glass. Revision 1  

SciTech Connect

The Waste Acceptance Preliminary Specifications (WAPS) require estimates of the heat generation rate of DWPF waste glasses. Estimates of the heat generation rates of projected glass compositions are to be reported in the Waste Form Qualification Report. Similar estimates for actual production glasses are to be reported in the Production Records. In this report, a method of calculating the heat generation rate from the radionuclide inventory is provided. Application of the method to the DWPF Design-Basis glass indicates that the heat generation rate can be accurately estimated from the Sr-90, Y-90, Cs-137, Ba-137m, and Pu-238 contents alone.

Plodinec, M.J.

1992-03-17T23:59:59.000Z

59

Method of calculation of heat generation rates for DWPF glass. Revision 2  

SciTech Connect

The Waste Acceptance Preliminary Specifications (WAPS) require estimates of the heat generation rate of DWPF waste glasses. Estimates of the heat generation rates of projected glass compositions are to be reported in the Waste Form Qualification Report. Similar estimates for actual production glasses are to be reported in the Production Records. In this report, a method of calculating the heat generation rate from the radionuclide inventory is provided. Application of the method to the DWPF Design-Basis glass indicates that the heat generation rate can be accurately estimated from the Sr-90, Y-90, Cs-137, Ba-137m, and Pu-238 contents alone.

Plodinec, M.J.

1993-02-04T23:59:59.000Z

60

Degrees of freedom and optimal operation of simple heat pump cycles  

E-Print Network (OSTI)

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

Skogestad, Sigurd

Note: This page contains sample records for the topic "operating heat rate" 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

Heat transfer rate of a closed-loop oscillating heat pipe with check valves using silver nanofluid as working fluid  

Science Journals Connector (OSTI)

This research investigated the effect of aspect ratios (evaporator length to inner diameter of capillary tube), inclination angles, and concentrations of silver nanofluid on the heat transfer rate of a closed-loo...

S. Wannapakhe; S. Rittidech; B. Bubphachot

2009-06-01T23:59:59.000Z

62

Combined Operation of Solar Energy Source Heat Pump, Low-vale Electricity and Floor Radiant System  

E-Print Network (OSTI)

solar energy, low-vale electricity as heat sources in a floor radiant system are analyzed. This paper presents a new heat pump system and discusses its operational modes in winter....

Liu, G.; Guo, Z.; Hu, S.

2006-01-01T23:59:59.000Z

63

Journal of Thermal Biology 33 (2008) 711 Physiological and behavioral control of heating and cooling rates  

E-Print Network (OSTI)

; Cooling rate; Heating rate; Physiological thermoregulation; Rubber boa; Temperature 1. Introduction Body temperature greatly impacts the ecology, behavior, and physiology of reptiles (Huey, 1982; Peterson, 1987; Peterson et al., 1993). Consequently, many species of reptiles thermoregulate to maintain body temperatures

Dorcas, Michael E.

64

Effect of Turbulence Fluctuations on Surface Heating Rate in Hypersonic Turbulent  

E-Print Network (OSTI)

Effect of Turbulence Fluctuations on Surface Heating Rate in Hypersonic Turbulent Boundary Layers) of reacting hypersonic turbulent boundary layers at conditions typical of reen- try vehicles. Surface heat in designing hypersonic vehicles is to predict aerothermo- dynamic heating. When the boundary layer

Martín, Pino

65

Improving Heating System Operations Using Water Re-Circulation  

E-Print Network (OSTI)

In order to solve the imbalance problem of a heating system, brought about by consumer demand and regulation, and save the electricity energy consumed by a circulation pump, a water mixing and pressure difference control heating system is proposed...

Li, F.; Han, J.

2006-01-01T23:59:59.000Z

66

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

E-Print Network (OSTI)

Evidence for thermalization of surface-desorbed molecules at heating rates of 108 K/s C. R of aniline-d7 from a single-crystal surface 0001 of sapphire Al2O3 at a heating rate on the order of 108 K.e., pulsed heating of the sapphire surface on the nanosecond time scale leads to thermal desorption and rapid

Zare, Richard N.

67

Numerical Study of Convective Heat Transfer in Flat Tube Heat Exchangers Operating in Self-Sustained Oscillatory Flow Regimes  

E-Print Network (OSTI)

Laminar, two-dimensional, constant-property numerical simulations of flat tube heat exchanger devices operating in flow regimes in which self-sustained oscillations occur were performed. The unsteady flow regimes were transition flow regimes...

Fullerton, Tracy

2012-02-14T23:59:59.000Z

68

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

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

ProductsCloud Properties and Radiative Heating Rates for ProductsCloud Properties and Radiative Heating Rates for TWP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Cloud Properties and Radiative Heating Rates for TWP 2002.01.01 - 2012.02.08 Site(s) TWP General Description A cloud properties and radiative heating rates dataset is presented where cloud properties retrieved using lidar and radar observations are input into a radiative transfer model to compute radiative fluxes and heating rates at three ARM sites located in the Tropical Western Pacific (TWP) region. The cloud properties retrieval is a conditional retrieval that applies various retrieval techniques depending on the available data, that is if lidar, radar or both instruments detect cloud. This Combined Remote

69

Parametric sensitivity study of operating and design variables in wellbore heat exchangers  

Science Journals Connector (OSTI)

A numerical study was conducted to evaluate the potential for using Wellbore Heat Exchangers (WBHX) to extract heat for use in electricity generation. Variables studied included operational parameters such as wellbore geometries, working fluid properties, circulation rates, and regional properties including basal heat flux and formation rock type. Energy extraction is strongly affected by fluid residence time, heat transfer contact area, and formation thermal properties. Water appears to be the most appropriate working fluid. The effects of tubing properties and casing lengths are of second-order. On the basis of a sensitivity study, a Best Case model was simulated, and results compared against the geothermal fluid requirements of existing power generation plants that use low-temperature geothermal fluids. Even assuming ideal work conversion to electricity, a WBHX cannot supply sufficient energy to generate 200kWe at the onset of pseudo-steady-state (PSS) conditions. Using realistic conversion efficiencies it is unlikely that the system would be able to generate 50kWe at the onset of PSS.

Gopi Nalla; G. Michael Shook; Gregory L. Mines; K. Kit Bloomfield

2005-01-01T23:59:59.000Z

70

Convergence Rates with Inexact Non-expansive Operators  

E-Print Network (OSTI)

The power of convex relaxation: near-optimal matrix completion. IEEE Trans. Inform. ... On the numerical solution of heat conduction problems in two and three

2014-06-11T23:59:59.000Z

71

Heat-and-Run: Leveraging SMT and CMP to Manage Power Density Through the Operating System  

E-Print Network (OSTI)

Heat-and-Run: Leveraging SMT and CMP to Manage Power Density Through the Operating System Mohamed and thermal ability of packages to dissipate heat. Power den- sity is characterized by localized chip hot Performance, Reliability Keywords Power density, heat, CMP, SMT, migration 1 INTRODUCTION Power

Vijaykumar, T. N.

72

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

73

High energy bursts from a solid state laser operated in the heat capacity limited regime  

DOE Patents (OSTI)

High energy bursts are produced from a solid state laser operated in a heat capacity limited regime. Instead of cooling the laser, the active medium is thermally well isolated. As a result, the active medium will heat up until it reaches some maximum acceptable temperature. The waste heat is stored in the active medium itself. Therefore, the amount of energy the laser can put out during operation is proportional to its mass, the heat capacity of the active medium, and the temperature difference over which it is being operated. The high energy burst capacity of a heat capacity operated solid state laser, together with the absence of a heavy, power consuming steady state cooling system for the active medium, will make a variety of applications possible. Alternately, cooling takes place during a separate sequence when the laser is not operating. Industrial applications include new material working processes. 5 figs.

Albrecht, G.; George, E.V.; Krupke, W.F.; Sooy, W.; Sutton, S.B.

1996-06-11T23:59:59.000Z

74

High energy bursts from a solid state laser operated in the heat capacity limited regime  

DOE Patents (OSTI)

High energy bursts are produced from a solid state laser operated in a heat capacity limited regime. Instead of cooling the laser, the active medium is thermally well isolated. As a result, the active medium will heat up until it reaches some maximum acceptable temperature. The waste heat is stored in the active medium itself. Therefore, the amount of energy the laser can put out during operation is proportional to its mass, the heat capacity of the active medium, and the temperature difference over which it is being operated. The high energy burst capacity of a heat capacity operated solid state laser, together with the absence of a heavy, power consuming steady state cooling system for the active medium, will make a variety of applications possible. Alternately, cooling takes place during a separate sequence when the laser is not operating. Industrial applications include new material working processes.

Albrecht, Georg (Livermore, CA); George, E. Victor (Livermore, CA); Krupke, William F. (Pleasanton, CA); Sooy, Walter (Pleasanton, CA); Sutton, Steven B. (Manteca, CA)

1996-01-01T23:59:59.000Z

75

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

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

Explores in-cylinder mechanisms by which fuel reactivity stratification via a two fuel system affects premixed charge compression ignition heat release rate to achieve diesel-like efficiency

76

Operation characteristics of cylindrical miniature grooved heat pipe using aqueous CuO nanofluids  

SciTech Connect

An experimental study was performed to investigate the operation characteristics of a cylindrical miniature grooved heat pipe using aqueous CuO nanofluid as the working fluid at some steady cooling conditions. The experiments were carried out under both the steady operation process and the unsteady startup process. The experiment results show that substituting the nanofluid for water as the working fluid can apparently improve the thermal performance of the heat pipe for steady operation. The total heat resistance and the maximum heat removal capacity of the heat pipe using nanofluids can maximally reduce by 50% and increase by 40% compared with that of the heat pipe using water, respectively. For unsteady startup process, substituting the nanofluid for water as the working fluid, cannot only improve the thermal performance, but also reduce significantly the startup time. (author)

Wang, Guo-Shan; Song, Bin; Liu, Zhen-Hua [School of Mechanical Engineering, Shanghai Jiaotong University, 200240 Shanghai (China)

2010-11-15T23:59:59.000Z

77

THE CFB SUMMERSIDE PROJECT INITIAL OPERATING EXPERIENCE WITH 18 TPH AFBC HEATING BOILERS  

Science Journals Connector (OSTI)

ABSTRACT Initial operating experience with Canada's first commercial FBC boiler plant, located at CFB Summerside, PEI, is described. The plant, consisting of two boilers rated at 18,000 kg/h of steam at MCR, operating at 965 kPa saturated steam, is designed for high-sulphur coal with supplementary firing of wood chips. The boilers were operated intermittently from December 1982 until May 1983, and in May one boiler was subjected to an acceptance test campaign of about two weeks, during which it performed satisfactorily, at loads ranging from 110% MCR to the maximum design turndown ratio of 4.5:1. Assessment of its performance in terms of efficiency and emissions awaits completion of laboratory analyses and data reduction. Careful control of limestone sizing is required to avoid the problems with cold fluidization which were encountered during commissioning. Also, high moisture and fines in the coal caused significant problems in the materials handling system. Some erosion of boiler tubes in the bed zone was observed. The affected areas were covered with a thin layer of hard refractory to prevent further deterioration. This does not appear to have a detrimental effect on steam output. Further work remains to be done, but it appears likely that during the next heating season both boilers will be fully commissioned and all requirements for acceptance will be met. KEYWORDS Fluidized-bed combustion, coal combustion, boiler operation.

V.V. Razbin; F.D. Friedrich

1984-01-01T23:59:59.000Z

78

Investigation of the effects of heating rate on coking of shale during retorting  

SciTech Connect

The retorting of oil shale distributes organic carbon among three possible products: the liquid product, the noncondensible product, and the residual carbon (coke). The production of coke is detrimental because of the economic effects caused by the loss of organic carbon to this relatively intractable carbon form. Two reference oil shales, a Mahogany zone, Parachute Creek Member, Green River Formation oil shale from Colorado and a Clegg Creek Member, New Albany oil shale from Kentucky, were studied to evaluate the conditions that affect coke production during retorting. The variable that was studied in these experiments was the heating rate during retorting because heating rate has been indicated to have a direct effect on coke production (Burnham and Clarkson 1980). The six heating rates investigated covered the range from 1 to 650/degree/C/h (1.8 to 1169/degree/F/h). The data collected during these experiments were evaluated statistically in order to identify trends. The data for the eastern reference oil shale indicated a decrease in coke formation with increases in the heating rate. The liquid and noncondensible product yields both increased with increasing heating rate. The distribution of products in relation to retort heating rate follows the model suggested by Burnham and Clarkson (1980). Coke production during the retorting of western reference oil shale was found to be constant in relation to heating rate. The liquid product yield increased with increasing heating rate but the trend could not be verified at the 95% confidence level. The coke production observed in these experiments does not follow the prediction of the model. This may indicate that coke formation occurs early in the retorting process and may be limited by the availability of organic materials that form coke. 6 refs., 10 tabs.

Guffey, F.D.; Hunter, D.E.

1988-02-01T23:59:59.000Z

79

Preliminary Retro-Commissioning Study on Optimal Operation for the Heat Source System of a District Heating Cooling Plant  

E-Print Network (OSTI)

Heating Water Suuply Chilled Water Return Heating Water Return To User New System ESL-IC-08-10-57 Proceedings of the Eighth International Conference for Enhanced Building Operations, Berlin, Germany, October 20-22, 2008 2 attract attention due..., R6 450 1, 1 ESL-IC-08-10-57 Proceedings of the Eighth International Conference for Enhanced Building Operations, Berlin, Germany, October 20-22, 2008 3 (one office building and one building with hotel rooms and leisure facilities) since November...

Shingu, H.; Yoshida, H.; Wang, F.; Ono, E.

80

Carbonization of Coal Effects of Variation of Rate of Heating during the Carbonization of a Typical Coking Coal  

Science Journals Connector (OSTI)

Carbonization of Coal Effects of Variation of Rate of Heating during the Carbonization of a Typical Coking Coal ...

William B. Warren

1935-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "operating heat rate" 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

Carbonization of Coal Evaluation of Effects of Rate of Heating and of Maximum Temperature on Pyrolysis of a Coking Coal  

Science Journals Connector (OSTI)

Carbonization of Coal Evaluation of Effects of Rate of Heating and of Maximum Temperature on Pyrolysis of a Coking Coal ...

William B. Warren

1935-01-01T23:59:59.000Z

82

Heat Kernel Coefficients for Two-Dimensional Schrodinger Operators  

E-Print Network (OSTI)

In this note, we compute the Hadamard coefficients of (algebraically) integrable Schrodinger operators in two dimensions. These operators first appeared in [BL] and [B] in connection with Huygens' principle, and our result completes, in a sense, the investigation initiated in those papers.

Yuri Berest; Tim Cramer; Farkhod Eshmatov

2007-10-26T23:59:59.000Z

83

High Operating Temperature Liquid Metal Heat Transfer Fluids  

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

Liquid Metal Liquid Metal Heat Transfer Fluids UCLA, UCB, Yale DE-EE0005941 | April 15, 2013 | Ju 1.1 Thermochemistry modeling * Continue CALPHAD based calculations to search for optimal ternary alloy compositions. * Initiate development of liquid density models. 1.2 Combinatorial synthesis and characterization * Pipe-Liquid interaction of compositional library * More alloys, alloy additions and effect on liquidus temperatures * Iteratively optimize the compositions. 1.3 Corrosion characterization and mitigation * Tune static corrosion testing systems for testing over an extended period of time. * Perform analysis of the micro mechanical testing on the oxide layers. 1.4 Heat transfer characterization and modeling * Complete the construction of the flow loop and perform experiments to measure

84

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

SciTech Connect

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

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

2014-03-01T23:59:59.000Z

85

Effects of different operating conditions of Gonen geothermal district heating system on its annual performance  

Science Journals Connector (OSTI)

Abstract In this paper, the effects of different operating conditions of the Gonen geothermal district heating system (GDHS) on its annual energy and exergy performance are investigated. The system parameters such as temperature, pressure and flow rate are monitored by using fixed and portable measuring instruments over a one-year period. Thus the main differences in the annual system operation are detected. The measurements show that the Gonen GDHS has six different operating cases depending on the outside temperature throughout the year. The energy and exergy analysis of the system is carried out for each case using the actual system parameters at the corresponding reference temperatures, which are 3.86, 7.1, 8.88, 11.83, 15.26 and 20.4C. The highest and lowest energy (57.32%, 35.64%) and exergy (55.76%, 41.42%) efficiencies of the overall system are calculated at the reference temperatures of 15.26C and 3.86C, respectively. Besides, taking the six case-based energy and exergy analyses into account, the annual average energy and exergy efficiencies are determined to be 45.24% and 47.33%, respectively.

Asiye Aslan; Bedri Yksel; Tu?rul Akyol

2014-01-01T23:59:59.000Z

86

On the maximum pressure rise rate in boosted HCCI operation  

E-Print Network (OSTI)

This paper explores the combined effects of boosting, intake air temperature, trapped residual gas fraction, and dilution on the Maximum Pressure Rise Rate (MPRR) in a boosted single cylinder gasoline HCCI engine with ...

Wildman, Craig B.

87

Operator renewal theory and mixing rates for dynamical systems with in nite measure  

E-Print Network (OSTI)

Operator renewal theory and mixing rates for dynamical systems with in#12;nite measure Ian of operator renewal sequences in the context of in#12;nite ergodic theory. For large classes of dynamical for mixing rates. Sarig [37] introduced a powerful new technique, operator renewal theory, to obtain precise

88

Performance of an experimental ground-coupled heat pump system for heating, cooling and domestic hot-water operation  

Science Journals Connector (OSTI)

Abstract The ground-coupled heat pump (GCHP) system is a type of renewable energy technology providing space heating and cooling as well as domestic hot water. However, experimental studies on GCHP systems are still insufficient. This paper first presents an energy-operational optimisation device for a GCHP system involving insertion of a buffer tank between the heat pump unit and fan coil units and consumer supply using quantitative adjustment with a variable speed circulating pump. Then, the experimental measurements are used to test the performance of the GCHP system in different operating modes. The main performance parameters (energy efficiency and CO2 emissions) are obtained for one month of operation using both classical and optimised adjustment of the GCHP system, and a comparative analysis of these performances is performed. In addition, using TRNSYS (Transient Systems Simulation) software, two simulation models of thermal energy consumption in heating, cooling and domestic hot-water operation are developed. Finally, the simulations obtained using TRNSYS are analysed and compared to experimental data, resulting in good agreement and thus the simulation models are validated.

Calin Sebarchievici; Ioan Sarbu

2015-01-01T23:59:59.000Z

89

Heating rates in collisionally opaque alkali-metal atom traps: Role of secondary collisions  

Science Journals Connector (OSTI)

Grazing collisions with background gas are the major cause of trap loss and trap heating in atom traps. To first order, these effects do not depend on the trap density. In collisionally opaque trapped atom clouds, however, scattered atoms with an energy E larger than the effective trap depth Eeff, which are destined to escape from the atom cloud, will have a finite probability for a secondary collision. This results in a contribution to the heating rate that depends on the column density ?nl? of the trapped atoms, i.e., the product of density and characteristic size of the trap. For alkali-metal atom traps, secondary collisions are quite important due to the strong long-range interaction with like atoms. We derive a simple analytical expression for the secondary heating rate, showing a dependency proportional to ?nl??Eeff1/2. When extrapolating to a vanishing column density, only primary collisions with the background gas will contribute to the heating rate. This contribution is rather small, due to the weak long-range interaction of the usual background gas species in an ultrahigh-vacuum systemHe, Ne, or Arwith the trapped alkali-metal atoms. We conclude that the transition between trap-loss collisions and heating collisions is determined by a cutoff energy 200??K<~Eeff<~400??K, much smaller than the actual trap depth E in most magnetic traps. Atoms with an energy Eeffheating rates for the alkali-metal atoms Li through Cs as a function of the effective trap depth, the column density of the trap, and the species in the background gas. The predictions of our model are in good agreement with the experimental data of Myatt for heating rates in high-density 87Rb-atom magnetic traps at JILA, including the effect of the rf shield and the composition of the background gas. It is shown that collisions with atoms from the Oort cloud also contribute to the heating rate. For 85Rb the calculated heating rate is below the experimentally observed value at JILA, supporting the idea that inelastic collisions in the trap are the major source of heating.

H. C. W. Beijerinck

2000-11-15T23:59:59.000Z

90

Photo-heating and supernova feedback amplify each other's effect on the cosmic star formation rate  

E-Print Network (OSTI)

Photo-heating associated with reionisation and kinetic feedback from core-collapse supernovae have previously been shown to suppress the high-redshift cosmic star formation rate. Here we investigate the interplay between photo-heating and supernova feedback using a set of cosmological, smoothed particle hydrodynamics simulations. We show that photo-heating and supernova feedback mutually amplify each other's ability to suppress the star formation rate. Our results demonstrate the importance of the simultaneous, non-independent inclusion of these two processes in models of galaxy formation to estimate the strength of the total negative feedback they exert. They may therefore be of particular relevance to semi-analytic models in which the effects of photo-heating and supernova feedback are implicitly assumed to act independently of each other.

Andreas H. Pawlik; Joop Schaye

2008-12-15T23:59:59.000Z

91

California Federal Facilities: Rate-Responsive Buidling Operating for Deeper Cost and Energy Savings  

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

Fact sheet from the Federal Energy Management Program (FEMP) describes rate-responsive building operations for cost and energy savings in California federal facilities.

92

Inverse bremsstrahlung heating rate in xenon clusters in the eikonal approximation  

SciTech Connect

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

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

2013-03-15T23:59:59.000Z

93

:MEASUREMENTS OF ELECTRON CYCLOlRON HEATING RATES J. D. Barter, J. C. Sprott, K. L. Wong  

E-Print Network (OSTI)

53706 ABSTRACT Electron cyclotron heating rates have been measured for plasmas in a toroidal octupole Energy Corrrrnission. #12;2 Electron cyclotron heating has been a standard technique for producing hot:MEASUREMENTS OF ELECTRON CYCLOlRON HEATING RATES by J. D. Barter, J. C. Sprott, K. L. Wong Jillle

Sprott, Julien Clinton

94

Life Cycle cost Analysis of Waste Heat Operated Absorption Cooling Systems for Building HVAC Applications  

E-Print Network (OSTI)

was used to calculate the PWC of the system for annual operating hours of 8760 and the same is compared with the electric based vapour compression chiller (VCRS) of same capacity. The life cycle cost (LCC) of waste heat operated absorption chiller...

Saravanan, R.; Murugavel, V.

2010-01-01T23:59:59.000Z

95

Experimental and thermodynamical analyses of the diesel exhaust vortex generator heat exchanger for optimizing its operating condition  

Science Journals Connector (OSTI)

Abstract In this research, a vortex generator heat exchanger is used to recover exergy from the exhaust of an OM314 diesel engine. Twenty vortex generators with 30 angle of attack are used to increase the heat recovery as well as the low back pressure in the exhaust. The experiments are prepared for five engine loads (0, 20, 40, 60 and 80% of full load), two exhaust gases amount (50and 100%) and four water mass flow rates (50, 40, 30 and 20g/s). After a thermodynamical analysis on the obtained data, an optimization study based on Central Composite Design (CCD) is performed due to complex effect of engine loads and water mass flow rates on exergy recovery and irreversibility to reach the best operating condition.

M. Hatami; D.D. Ganji; M. Gorji-Bandpy

2015-01-01T23:59:59.000Z

96

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

E-Print Network (OSTI)

. In addition, the analysis is to identify the most dominant variables for enhancing the lake dissipation rate and hence provide cost-effective measures to enhance the power plant efficiency. The case study power plant has 900 MW of power capacity with five...

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

2011-01-01T23:59:59.000Z

97

Distortion operator and Entanglement Information Rate Distortion of Quantum Gaussian Source  

E-Print Network (OSTI)

Quantum random variable, distortion operator are introduced based on canonical operators. As the lower bound of rate distortion, the entanglement information rate distortion is achieved by Gaussian map for Gaussian source. General Gaussian maps are further reduced to unitary transformations and additive noises from the physical meaning of distortion. The entanglement information rate distortion function then are calculated for one mode Gaussian source. The rate distortion is accessible at zero distortion point. For pure state, the rate distortion function is always zero. In contrast to the distortion defined via fidelity, our definition of the distortion makes it possible to calculate the entanglement information rate distortion function for Gaussian source.

Xiao-yu Chen

2005-11-30T23:59:59.000Z

98

Operator renewal theory and mixing rates for dynamical systems with infinite measure  

E-Print Network (OSTI)

Operator renewal theory and mixing rates for dynamical systems with infinite measure Ian Melbourne renewal sequences in the context of infinite ergodic theory. For large classes of dynamical systems technique, operator renewal theory, to obtain precise asymptotics and hence sharp mixing rates

99

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

SciTech Connect

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

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

1995-01-01T23:59:59.000Z

100

A detailed MILP optimization model for combined cooling, heat and power system operation planning  

Science Journals Connector (OSTI)

Abstract A detailed optimization model is presented for planning the short-term operation of combined cooling, heat and power (CCHP) energy systems. The purpose is, given the design of a cogeneration system, to determine an operating schedule that minimizes the total operating and maintenance costs minus the revenue due to the electricity sold to the grid, while taking into account time-varying loads, tariffs and ambient conditions. The model considers the simultaneous use of different prime movers (generating electricity and heat), boilers, compression heat pumps and chillers, and absorption chillers to satisfy given electricity, heat and cooling demands. Heat and cooling load can be stored in storage tanks. Units can have one or two operative variables, highly nonlinear performance curves describing their off-design behavior, and limitations or penalizations affecting their start-up/shut-down operations. To exploit the effectiveness of state-of-the-art Mixed Integer Linear Program (MILP) solvers, the resulting Mixed Integer Nonlinear Programming (MINLP) model is converted into a MILP by appropriate piecewise linear approximation of the nonlinear performance curves. The model, written in the AMPL modeling language, has been tested on several plant test cases. The computational results are discussed in terms of the quality of the solutions, the linearization accuracy and the computational time.

Aldo Bischi; Leonardo Taccari; Emanuele Martelli; Edoardo Amaldi; Giampaolo Manzolini; Paolo Silva; Stefano Campanari; Ennio Macchi

2014-01-01T23:59:59.000Z

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


101

Understanding Utility Rates or How to Operate at the Lowest $/BTU  

E-Print Network (OSTI)

:F.~:brP'RQJ~:Cr::::::::: ::: :::] by LONE STAR GAS COMPANY JIM PHILLIPS, P.E., CEM IEQUIPMENT D A T Ai IENERGY DAT Ai KW Gas Rate: $4.86 per MCFGenerator Size: 5"00 Coqen Rate: $3.00 Iper MCF Recoverable Heat: 4.3' MMBH I _ Fuel Consumption: 8.0 MCFH Electric Rate $6.80 per...:F.~:brP'RQJ~:Cr::::::::: ::: :::] by LONE STAR GAS COMPANY JIM PHILLIPS, P.E., CEM IEQUIPMENT D A T Ai IENERGY DAT Ai KW Gas Rate: $4.86 per MCFGenerator Size: 5"00 Coqen Rate: $3.00 Iper MCF Recoverable Heat: 4.3' MMBH I _ Fuel Consumption: 8.0 MCFH Electric Rate $6.80 per...

Phillips, J. N.

102

Heat-affected zone and ablation rate of copper ablated with femtosecond laser  

SciTech Connect

We describe the experimental and molecular dynamics simulation study of crystalline copper (Cu) ablation using femtosecond lasers. This study is focused on the heat-affected zone after femtosecond laser ablation and the laser ablation rate. As a result of the x-ray diffraction measurement on the ablated surface, the crystallinity of the surface is partially changed from a crystal structure into an amorphous one. At the laser fluences below the ablation threshold, the entire laser energy coupled to the Cu target is absorbed, while during the fluence regime over the threshold fluence, the ablation rate depends on the absorption coefficient, and the residual energy which is not used for the ablation, is left in the Cu substrate. The heat-affected zone at the fluences below the threshold is estimated to be greater than that over the threshold fluence. In addition, the laser ablation of Cu is theoretically investigated by a two-temperature model and molecular dynamics (MD) simulation to explain the heat-affected zone and ablation rate. The MD simulation takes into account the electron temperature and thermal diffusion length calculated by the two-temperature model. Variation in the lattice temperature with time and depth is calculated by the MD simulation coupled with the two-temperature model. The experimental ablation rate and the heat-affected zone are theoretically well explained.

Hirayama, Yoichi; Obara, Minoru [Department of Electronics and Electrical Engineering, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan)

2005-03-15T23:59:59.000Z

103

Optimal Operation of a Waste Incineration Plant for District Heating Johannes Jaschke, Helge Smedsrud, Sigurd Skogestad*, Henrik Manum  

E-Print Network (OSTI)

Optimal Operation of a Waste Incineration Plant for District Heating Johannes J¨aschke, Helge@chemeng.ntnu.no off-line. This systematic approach is here applied to a waste incineration plant for district heating. In district heating networks, operators usually wish to ob- tain the lowest possible return temperature

Skogestad, Sigurd

104

A comparative study on conventional and advanced exergetic analyses of geothermal district heating systems based on actual operational data  

Science Journals Connector (OSTI)

This paper comparatively evaluates exergy destructions of a geothermal district heating system (GDHS) using both conventional and advanced exergetic analysis methods to identify the potential for improvement and the interactions among the components. As a real case study, the Afyon GDHS in Afyonkarahisar, Turkey, is considered based on actual operational data. For the first time, advanced exergetic analysis is applied to the GDHSs, in which the exergy destruction rate within each component is split into unavoidable/avoidable and endogenous/exogenous parts. The results indicate that the interconnections among all the components are not very strong. Thus, one should focus on how to reduce the internal inefficiency (destruction) rates of the components. The highest priority for improvement in the advanced exergetic analysis is in the re-injection pump (PM-IX), while it is the heat exchanger (HEX-III) in the conventional analysis. In addition, there is a substantial influence on the overall system as the total avoidable exergy destruction rate of the heat exchanger (HEX-V) has the highest value. On the overall system basis, the value for the conventional exergetic efficiency is determined to be 29.29% while that for the modified exergetic efficiency is calculated to be 34.46% through improving the overall components.

Arif Hepbasli; Ali Keeba?

2013-01-01T23:59:59.000Z

105

Operational Performance Results of an Innovative Solar Thermal Cooling and Heating Plant  

Science Journals Connector (OSTI)

Solar thermal cooling and heating plants with single-effect sorption chillers/heat pumps promise primary energy savings compared to electric vapor compression chiller systems. Yet, the need of auxiliary electric a nd fossil energy for the operation and backup of the thermal cooling system possibly worsen the primary energy balance. An auspicious approach to overcome this problem is the application of a more efficient multi -stage sorption chiller with flexible operational modes. A pilot installation of that innovative solar thermal heating and cooling plant comprising a two stage absorption chiller/heat pump is presented. Beginning with the motivation and the system concept, a detailed analysis of the 2011/2012 cooling and heating periods is shown. The influence of the different system components especially the absorption chiller on the overall system performance is analyzed and a comparison to data from a detailed dynamic model is carried out. Recommendations for the improvement with respect to efficiency and economic aspects are given based on the installation process and the operational experience gained in the last 1 years.

Manuel Riepl; Felix Loistl; Richard Gurtner; Martin Helm; Christian Schweigler

2012-01-01T23:59:59.000Z

106

Operation of the CAPRICE electron cyclotron resonance ion source applying frequency tuning and double frequency heating  

SciTech Connect

The properties of the electromagnetic waves heating the electrons of the ECR ion sources (ECRIS) plasma affect the features of the extracted ion beams such as the emittance, the shape, and the current, in particular for higher charge states. The electron heating methods such as the frequency tuning effect and the double frequency heating are widely used for enhancing the performances of ECRIS or even for the routine operation during the beam production. In order to better investigate these effects the CAPRICE ECRIS has been operated using these techniques. The ion beam properties for highly charged ions have been measured with beam diagnostic tools. The reason of the observed variations of this performance can be related to the different electromagnetic field patterns, which are changing inside the plasma chamber when the frequency is varying.

Maimone, F. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Planckstr. 1, 64291 Darmstadt (Germany); Universita degli Studi di Catania, D.M.F.C.I, Viale A. Doria 6, 95125 Catania (Italy); Tinschert, K.; Lang, R.; Maeder, J.; Rossbach, J.; Spaedtke, P. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Planckstr. 1, 64291 Darmstadt (Germany); Celona, L. [INFN-LNS, Via S. Sofia 62, 95123 Catania (Italy)

2012-02-15T23:59:59.000Z

107

Entirely passive heat-pipe apparatus capable of operating against gravity  

DOE Patents (OSTI)

The disclosure is directed to an entirely passive heat pipe apparatus capable of operating against gravity for vertical distances in the order of 3 to 7 and more. A return conduit into which an inert gas is introduced is used to lower the specific density of the working fluid so that it may be returned a greater vertical distance from condenser to evaporator.

Koenig, D.R.

1981-02-11T23:59:59.000Z

108

Melting processes of oligomeric ? and ? isotactic polypropylene crystals at ultrafast heating rates  

SciTech Connect

The melting behaviors of ? (stable) and ? (metastable) isotactic polypropylene (iPP) crystals at ultrafast heating rates are simulated with atomistic molecular dynamics method. Quantitative information about the melting processes of ?- and ?-iPP crystals at atomistic level is achieved. The result shows that the melting process starts from the interfaces of lamellar crystal through random dislocation of iPP chains along the perpendicular direction of lamellar crystal structure. In the melting process, the lamellar crystal gradually expands but the corresponding thickness decreases. The analysis shows that the system expansion lags behind the crystallinity decreasing and the lagging extents for ?- and ?-iPP are significantly different. The apparent melting points of ?- and ?-iPP crystals rise with the increase of the heating rate and lamellar crystal thickness. The apparent melting point of ?-iPP crystal is always higher than that of ?-iPP at differently heating rates. Applying the Gibbs-Thomson rule and the scaling property of the melting kinetics, the equilibrium melting points of perfect ?- and ?-iPP crystals are finally predicted and it shows a good agreement with experimental result.

Ji, Xiaojing [School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China)] [School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); He, Xuehao, E-mail: xhhe@tju.edu.cn, E-mail: scjiang@tju.edu.cn [Department of Chemistry, School of Science, Tianjin University, and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072 (China)] [Department of Chemistry, School of Science, Tianjin University, and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072 (China); Jiang, Shichun, E-mail: xhhe@tju.edu.cn, E-mail: scjiang@tju.edu.cn [School of Material, Tianjin University, Tianjin 300072 (China)] [School of Material, Tianjin University, Tianjin 300072 (China)

2014-02-07T23:59:59.000Z

109

SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer  

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

High Operating Temperature Liquid Metal Heat Transfer Fluids High Operating Temperature Liquid Metal Heat Transfer Fluids UCLA logo University of California Berkeley logo Yale logo Four graphics in a grid that represent the sputtering technique being used in this project. Combinatorial screening and high throughput characterization of materials will be used to identify, develop, and demonstrate metal alloys that meet the MURI HOT Fluids targets suitable for CSP applications. The University of California, Los Angeles, the University of California, Berkeley, and Yale University The University of California, Los Angeles (UCLA), along with partners at the University of California, Berkeley, and Yale University, under the 2012 Multidisciplinary University Research Initiative (MURI): High Operating Temperature (HOT) Fluids funding opportunity, is investigating the use of metal alloys as a heat transfer fluid (HTF) in concentrating solar power (CSP) systems operating at temperatures in excess of 800°C. By allowing higher temperature operation, CSP systems can achieve greater efficiencies and thereby reduce the overall cost of electricity production.

110

Heat kernel of non-minimal gauge field kinetic operators on Moyal plane  

E-Print Network (OSTI)

We generalize the Endo formula originally developed for the computation of the heat kernel asymptotic expansion for non-minimal operators in commutative gauge theories to the noncommutative case. In this way, the first three non-zero heat trace coefficients of the non-minimal U(N) gauge field kinetic operator on the Moyal plane taken in an arbitrary background are calculated. We show that the non-planar part of the heat trace asymptotics is determined by U(1) sector of the gauge model. The non-planar or mixed heat kernel coefficients are shown to be gauge-fixing dependent in any dimension of space-time. In the case of the degenerate deformation parameter the lowest mixed coefficients in the heat expansion produce non-local gauge-fixing dependent singularities of the one-loop effective action that destroy the renormalizability of the U(N) model at one-loop level. The twisted-gauge transformation approach is discussed.

Alexei Strelchenko

2006-08-18T23:59:59.000Z

111

Integrated flue gas treatment for simulataneous emission control and heat rate improvement - demonstration project at Ravenswood  

SciTech Connect

Results are presented for electric-utility, residual-oil fired, field demonstration testing of advanced-design, heat-recovery type, flue gas sub-coolers that incorporate sulfite-alkali-based wet scrubbing for efficient removal of volatile and semi-volatile trace elements, sub-micron solid particulate matter, SO{sub 2} and SO{sub 3}. By innovative adaptation of wet collector system operation with methanol injection into the rear boiler cavity to convert flue-gas NO to No{sub 2}, simultaneous removal of NO{sub x} is also achieved. The focus of this integrated flue gas treatment (IFGT) technology development and demonstration-scale, continuous performance testing is an upward-gas-flow, indirectly water-cooled, condensing heat exchanger fitted with acid-proof, teflon-covered tubes and tubesheets and that provides a unique condensing (non-evaporative) wet-scrubbing mode to address air toxics control objectives of new Clean Air Act, Title III. Advantageous trace-metal condensation/nucleation/agglomeration along with substantially enhanced boiler efficiency is accomplished in the IFGT system by use of boiler makeup water as a heat sink in indirectly cooling boiler flue gas to a near-ambient-temperature, low-absolute-humidity, water-saturated state. Moreover, unique, innocuous, stack systems design encountered with conventional high-humidity, wet-scrubber operations. The mechanical design of this advanced flue-gas cooling/scrubbing equipment is based on more than ten years of commercial application of such units is downward-gas-flow design/operation for energy recovery, e.g. in preheating of makeup water, in residual-oil and natural-gas fired boiler operations.

Heaphy, J.; Carbonara, J.; Cressner, A. [Consolidated Edison Company, New York, NY (United States)] [and others

1995-06-01T23:59:59.000Z

112

Influence of the non-linearity of the collision operator on ion cyclotron resonance heating  

Science Journals Connector (OSTI)

The distribution function of ions heated in the ion cyclotron range of frequencies is obtained by solving the FokkerPlanck equation. For non-minority heating scenarios, the full non-linear Coulomb collision operator must be used in this equation. A method of resolution accounting for the complexity of this operator is presented. We consider a plasma immersed in a homogeneous magnetic field. The adopted method of resolution is based on an expansion of the distribution function in a series of Legendre polynomials. Results of the corresponding code non-linear FokkerPlanck in two-dimensional velocity space (NLFP-2D) are discussed for experimentally relevant JET-like parameters. The convergence of the Legendre expansion has been tested and the importance of the non-linear effects has been shown. Three different regimes, characterized by different modes of indirect ion heating and depending on the absorbed RF power density as well as the minority concentration, were identified. The NLFP-2D code has been used to study the validity of the Maxwellian approximation of the self-collision operator. One finds that this model is only correct in a very limited range of parameters, and leads mostly to an overestimation of the indirect ion heating.

F Louche

2004-01-01T23:59:59.000Z

113

An Efficient Approximation of the Coronal Heating Rate for use in Global Sun-Heliosphere Simulations  

Science Journals Connector (OSTI)

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

Steven R. Cranmer

2010-01-01T23:59:59.000Z

114

An Efficient Approximation of the Coronal Heating Rate for Use in Global Sun-Heliosphere Simulations  

E-Print Network (OSTI)

The origins of the hot solar corona and the supersonically expanding solar wind are still the subject of debate. A key obstacle in the way of producing realistic simulations of the Sun-heliosphere system is the lack of a physically motivated way of specifying the coronal heating rate. Recent one-dimensional models have been found to reproduce many observed features of the solar wind by assuming the energy comes from Alfven waves that are partially reflected, then dissipated by magnetohydrodynamic turbulence. However, the nonlocal physics of wave reflection has made it difficult to apply these processes to more sophisticated (three-dimensional) models. This paper presents a set of robust approximations to the solutions of the linear Alfven wave reflection equations. A key ingredient to the turbulent heating rate is the ratio of inward to outward wave power, and the approximations developed here allow this to be written explicitly in terms of local plasma properties at any given location. The coronal heating al...

Cranmer, Steven R

2009-01-01T23:59:59.000Z

115

Dynamic optimization of heated oil pipeline operation using PSODE algorithm  

Science Journals Connector (OSTI)

Abstract Crude oil, with relatively high viscosity, freezing-point and content of wax, is usually transported by heated oil pipelines (HOP) containing many pumping and heating stations. There are many different selections of operation parameters or values of pumps and heating furnaces, but all these different selections can satisfy output task and safety requirements. The power and fuel cost of pumping and heating account for 13% of the total energy consumption. For the energy saving purpose, it is necessary to optimize the HOP operations. In this paper a dynamic model of HOP was proposed and used to calculate the soil temperature field outside HOP, and then both the spatial and temporal distributions of pressure and temperature of field inside HOP. Using this calculation method and its results, an optimization model is established aiming at minimizing energy cost of running HOP, with outlet temperatures of each heating station, onoff states of each pump, and their head matrix of delivery as the optimization variables. Then a mixed algorithm combining differential evolution algorithm with particle swarm optimization algorithm is used to solve this model. The optimization results are applied to RizhaoYizheng digital long distance HOP (375km). Research shows that: verified by real time data acquired by the SCADA, the relative error of the dynamic models result is 4.042%, much less than that of the steady-state models result (22.67%). The optimized operation scheme can save 17.59% of energy cost for oil transportation task of 2640m3/h. Energy saving effect is remarkable.

Ming Zhou; Yu Zhang; Shijiu Jin

2015-01-01T23:59:59.000Z

116

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

E-Print Network (OSTI)

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

Romain Dubessy; Thomas Coudreau; Luca Guidoni

2008-12-17T23:59:59.000Z

117

Numerical study of the global axisymmetric circulation with varying heating and rotation rates  

SciTech Connect

A steady, axisymmetric model of the general circulation is developed as a basis for climate stability studies. The model includes the effects of heating, rotation, and internal friction, but neglects topography. It is assumed that the axisymmetric flow may be modeled by making the Boussinesq and deep convection approximations. The three unknowns are assumed to satisfy appropriate spectral expansions, and the three equations are then rearranged into a Galerkin representation. The number of degrees of freedom retained in the expansions is restricted to eight waves or less, which places the model in the class of highly truncated spectral models. The motions are forced by a specified heating distribution and dissipated through an eddy mixing coefficient formulation. The axisymmetric circulation is tested for stability to quasi-geostrophic disturbances. The orignial set of five primitive equations is reduced to a single equation governing the evolution of quasi-geostrophic potential vorticity. This equation is linearized about the axisymmetric state, and the stability of the disturbances is found by examining the eigenvalues associated with each disturbance. The application of the Boussinesq, deep convection, and quasi-geostrophic assumptions limits the ranges of the heating and rotation rates. For values not too far from typical atmospheric values, the model produces a stability boundary separating Rossby and Hadley flow.

Henderson, H.W.

1982-01-01T23:59:59.000Z

118

Measuring the shock-heating rate in the winds of O stars using X-ray line spectra  

Science Journals Connector (OSTI)

......College, Department of Physics and Astronomy, Swarthmore...Iowa, Department of Physics and Astronomy, Iowa...Technology, Department of Physics and Space Sciences...determine the shock-heating rate due to instabilities...plasma systematically passes through the temperature......

David H. Cohen; Zequn Li; Kenneth G. Gayley; Stanley P. Owocki; Jon O. Sundqvist; Vronique Petit; Maurice A. Leutenegger

2014-01-01T23:59:59.000Z

119

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

SciTech Connect

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

Riihimaki, Laura; Shippert, Timothy

2014-11-05T23:59:59.000Z

120

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

DOE Data Explorer (OSTI)

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

Riihimaki, Laura; Shippert, Timothy

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121

EIS-0302: Transfer of the Heat Source/Radioisotope Thermoelectric Generator Assembly and Test Operations From the Mound Site  

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

This EIS analyzes DOE's proposed transfer of the Heat Source/Radioisotope Thermoelectric Generator (HS/RTG) operations at the Mound Site near Miamisburg, Ohio, to an alternative DOE site.

122

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

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

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

123

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

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

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

124

Guide to Combined Heat and Power Systems for Boiler Owners and Operators  

SciTech Connect

Combined heat and power (CHP) or cogeneration is the sequential production of two forms of useful energy from a single fuel source. In most CHP applications, chemical energy in fuel is converted to both mechanical and thermal energy. The mechanical energy is generally used to generate electricity, while the thermal energy or heat is used to produce steam, hot water, or hot air. Depending on the application, CHP is referred to by various names including Building Cooling, Heating, and Power (BCHP); Cooling, Heating, and Power for Buildings (CHPB); Combined Cooling, Heating, and Power (CCHP); Integrated Energy Systems (IES), or Distributed Energy Resources (DER). The principal technical advantage of a CHP system is its ability to extract more useful energy from fuel compared to traditional energy systems such as conventional power plants that only generate electricity and industrial boiler systems that only produce steam or hot water for process applications. By using fuel energy for both power and heat production, CHP systems can be very energy efficient and have the potential to produce electricity below the price charged by the local power provider. Another important incentive for applying cogeneration technology is to reduce or eliminate dependency on the electrical grid. For some industrial processes, the consequences of losing power for even a short period of time are unacceptable. The primary objective of the guide is to present information needed to evaluate the viability of cogeneration for new or existing industrial, commercial, and institutional (ICI) boiler installations and to make informed CHP equipment selection decisions. Information presented is meant to help boiler owners and operators understand the potential benefits derived from implementing a CHP project and recognize opportunities for successful application of cogeneration technology. Topics covered in the guide follow: (1) an overview of cogeneration technology with discussions about benefits of applying cogeneration technology and barriers to implementing cogeneration technology; (2) applicable federal regulations and permitting issues; (3) descriptions of prime movers commonly used in CHP applications, including discussions about design characteristics, heat-recovery options and equipment, fuels and emissions, efficiency, maintenance, availability, and capital cost; (4) electrical generators and electrical interconnection equipment; (5) cooling and dehumidification equipment; (6) thermodynamic cycle options and configurations; (7) steps for evaluating the technical and economic feasibility of applying cogeneration technology; and (8) information sources.

Oland, CB

2004-08-19T23:59:59.000Z

125

Spectral effects on the transmittance, solar heat gain, and performance rating of glazing systems  

Science Journals Connector (OSTI)

This study investigates the potential changes in Solar Heat Gain Coefficient (SHGC) and Visible Transmittance (VT) ratings of vertical or tilted glazing systems that would result from a deliberate change in the reference spectrum used as Spectral Weighting Function (SWF). This SWF is necessary to evaluate broadband-average optical properties from their spectral values, and obtain the desired rating of such bulk properties. The \\{SWFs\\} currently specified by rating institutions in Europe and North America for SHGC and VT are now outdated, and their inadequacies are discussed. Six potential replacements, which have been recently adopted by ASTM are described, including three direct irradiance spectra and three global irradiance spectrum incident on tilted surfaces of various tilts (20, 37 and 90). Some of these spectra have been tailored for use in building energy applications, including Building-Integrated Photovoltaics (BIPV). The effect of tilt on the U-factor and hence SHGC of glazing systems used for skylights on roofs is discussed, using a representative dataset of 37 glazing system specimens. The spectral effects on SHGC induced by a change in the current North American SWF are also obtained for this dataset, and show small to moderate deviations from current ratings (?2% to +7% for windows, and ?3% to +11% for skylights). The variations in VT are within 2% for most glazing systems. To remove the current inconsistency in the \\{SWFs\\} used for SHGC and VT, it is recommended that a single SWF be used for both properties. For improved accuracy and reliance on active standards, it is also recommended that the SWF for SHGC and VT be either one of the two recent ASTM G197-08 global irradiance spectra, depending on application (incidence on a vertical surface for window applications, and incidence on a 20-tilted surface for skylight applications). No change in colorimetric calculations (based on the D65 illuminant) is recommended, however.

Christian A. Gueymard; William C. duPont

2009-01-01T23:59:59.000Z

126

Real-Time Combined Heat and Power Operational Strategy Using a Hierarchical Optimization Algorithm  

SciTech Connect

Existing attempts to optimize the operation of Combined Heat and Power (CHP) systems for building applications have two major limitations: the electrical and thermal loads are obtained from historical weather profiles; and the CHP system models ignore transient responses by using constant equipment efficiencies. This paper considers the transient response of a building combined with a hierarchical CHP optimal control algorithm to obtain a real-time integrated system that uses the most recent weather and electric load information. This is accomplished by running concurrent simulations of two transient building models. The first transient building model uses current as well as forecast input information to obtain short term predictions of the thermal and electric building loads. The predictions are then used by an optimization algorithm, i.e., a hierarchical controller, that decides the amount of fuel and of electrical energy to be allocated at the current time step. In a simulation, the actual physical building is not available and, hence, to simulate a real-time environment, a second, building model with similar but not identical input loads are used to represent the actual building. A state-variable feedback loop is completed at the beginning of each time step by copying, i.e., measuring, the state variable from the actual building and restarting the predictive model using these ?measured? values as initial conditions. The simulation environment presented in this paper features nonlinear effects such as the dependence of the heat exchanger effectiveness on their operating conditions. The results indicate that the CHP engine operation dictated by the proposed hierarchical controller with uncertain weather conditions have the potential to yield significant savings when compared to conventional systems using current values of electricity and fuel prices.

Yun, Kyung Tae; Cho, Heejin; Luck, Rogelio; Mago, Pedro J.

2011-06-01T23:59:59.000Z

127

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

SciTech Connect

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

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

1995-05-01T23:59:59.000Z

128

Estimation of Rate of Heat Release by Means of Oxygen Consumption Measurements  

E-Print Network (OSTI)

the heat release of combustible wall linings during full-scale room fire tests, William Parker, Huggett to the release of heat, the combustion process consumes oxygen. As part of his work on the ASTM E 84 tunnel test released per unit mass of material consumed (i.e., the specific heat of combustion), varied greatly

Womeldorf, Carole

129

Experimental study on heat transfer characteristics of internal heat exchangers for CO2 system under cooling condition  

Science Journals Connector (OSTI)

This paper presents the heat transfer characteristics of the internal heat exchanger (IHX) for CO2 heat pump system. The influence on the IHX length, the mass flow rate, the shape of IHX, the operating condition,...

Young Chul Kwon; Dae Hoon Kim; Jae Heon Lee

2009-03-01T23:59:59.000Z

130

Differential rates for district heating and the influence on the optimal retrofit strategy for multi-family buildings  

Science Journals Connector (OSTI)

When renovating existing multi-family buildings it is very important to implement the best retrofit strategy possible in order to minimize the remaining life-cycle cost for the building. If the building is heated with district heating this strategy of course changes due to the energy rate used by the utility. It is also very important for the utility that the consumer is encouraged to save energy when there is a need for it, i.e. during peak load conditions. Our paper shows that an accurate cost differential rate provides all these facilities.

Stig-Inge Gustafsson; Bjrn G. Karlsson; Bertil H. Sjholm

1987-01-01T23:59:59.000Z

131

Mathematical description of a boiler house operating jointly with a wind power plant and heat storage  

Science Journals Connector (OSTI)

A heat supply system is considered that contains, along with a boiler house, a wind power plant and heat storage. Methodical approaches for determining ... modes of the heat storage jointly with the wind power plant

A. V. Bezhan; V. A. Minin

2011-11-01T23:59:59.000Z

132

Cold End Inserts for Process Gas Waste Heat Boilers Air Products, operates hydrogen production plants, which utilize large waste heat boilers (WHB)  

E-Print Network (OSTI)

Cold End Inserts for Process Gas Waste Heat Boilers Overview Air Products, operates hydrogen walls. Air Products tasked our team to design an insert to place in the tubes of the WHB to increase flow velocity, thereby reducing fouling of the WHB. Objectives Air Products wishes that our team

Demirel, Melik C.

133

Energy efficient operation strategy design for the combined cooling, heating and power system.  

E-Print Network (OSTI)

??Combined cooling, heating and power (CCHP) systems are known as trigeneration systems, designed to provide electricity, cooling and heating simultaneously. The CCHP system has become (more)

Liu, Mingxi

2012-01-01T23:59:59.000Z

134

Shut-down dose rate analyses for the ITER electron cyclotron-heating upper launcher  

Science Journals Connector (OSTI)

Abstract The electron cyclotron resonance heating upper launcher (ECHUL) is going to be installed in the upper port of the ITER tokamak thermonuclear fusion reactor for plasma mode stabilization (neoclassical tearing modes and the sawtooth instability). The paper reports the latest neutronic modeling and analyses which have been performed for the ITER reference front steering launcher design. It focuses on the port accessibility after reactor shut-down for which dose rate (SDDR) distributions on a fine regular mesh grid were calculated. The results are compared to those obtained for the ITER Dummy Upper Port. The calculations showed that the heterogeneous ECHUL design gives rise to enhanced radiation streaming as compared to the homogenous dummy upper port. Therefore the used launcher geometry was upgraded to a more recent development stage. The inter-comparison shows a significant improvement of the launchers shielding properties but also the necessity to further upgrade the shielding performance. Furthermore, the analysis for the homogenous dummy upper port, which represents optimal shielding inside the launcher, demonstrates that the shielding upgrade also needs to include the launcher's environment.

Bastian Weinhorst; Arkady Serikov; Ulrich Fischer; Lei Lu; Peter Spaeh; Dirk Strauss

2014-01-01T23:59:59.000Z

135

Numerical Study on the Operating Performance of an Indirect Expansion Solar Assisted Multifunctional Heat Pump in Water Heating Mode  

Science Journals Connector (OSTI)

An indirect expansion solar assisted multifunctional heat pump (IE-SAMHP) is ... SAMHP consists of an all-glass evacuated-tube solar collector system, a compressor, two air-...

Ji Jie; Jiang Aiguo; Yang Jichun; Pei Gang

2009-01-01T23:59:59.000Z

136

Fuel consumption rate in a heat-powered unit analyzed as a function of the temperature and consumption ratio of the air  

Science Journals Connector (OSTI)

An analysis of fuel consumption for a heat-powered unit in the ... of ceramic materials is given. The heat consumption rate is analyzed as a function of ... generating the working medium, and of the consumption r...

N. A. Tyutin

2006-01-01T23:59:59.000Z

137

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

E-Print Network (OSTI)

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

Chiaverini, John

138

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

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

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

139

Steady state heat transfer experimental studies of LHC superconducting cables operating in cryogenic environment of superfluid helium  

E-Print Network (OSTI)

The heat management is a basic and fundamental aspect of the superconducting magnets used in the CERN Large Hadron Collider. Indeed, the coil temperature must be kept below the critical value, despite the heat which can be generated or deposited in the magnet during the normal operations. Therefore, this thesis work aims at determining the heating power which can be extracted from the superconducting cables of the LHC, specially through their electrical insulation which represents the main thermal barrier. An experimental measurement campaign in superfluid helium bath was performed on several samples reproducting the main LHC magnets. The heating power was generated in the sample by Joule heating and the temperature increase was measured by means of Cernox bare chip and thermocouples. An innovative instrumentation technique which also includes the in-situ calibration of the thermocouples was developed. A thorough uncertainty analysis on the overall measurement chain concluded the experimental setup. The prese...

Santandrea, Dario; Tuccillo, Raffaele;; Granieri, Pier Paolo.

140

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

SciTech Connect

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

Kelsey, Charles T. IV [Los Alamos National Laboratory

2012-05-09T23:59:59.000Z

Note: This page contains sample records for the topic "operating heat rate" 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

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

E-Print Network (OSTI)

Conditions Charge Pressure (psia) Firing Rate (KBTUH) Frequency (Hz) Power Piston Stroke (in.) Displacer the earlier analysis; these results are shown in Fig. 4. Working Fluid Charge Pressure (psia) Power Level (k was measured as the total enthalpy gain of the refrigerant across the compres- sor. Table 2 shows the range

Oak Ridge National Laboratory

142

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

SciTech Connect

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

Hufnagel, Todd C.

2014-06-09T23:59:59.000Z

143

A Simple Control Scheme for Near-optimal Operation of Parallel Heat Exchanger Systems  

E-Print Network (OSTI)

. In the chemical and process industries, large amounts of energy can be saved by using heat recovery in heat exchanger networks, which transfer energy in form of heat Corresponding author: email: skoge@ntnu.no, phone exchanger networks for saving energy and costs has led to a large body of research, and most

Skogestad, Sigurd

144

Feasibility Study of a Multi-Purpose Computer Program for Optimizing Heat Rates in Power Cycles  

E-Print Network (OSTI)

and future needs of the power industry follows. The discussion is restricted to steam turbine cycles of fossil or nuclear power plants, although some ECC's can be employed to a wider range of applications, such as analysis of different heat sources... and future needs of the power industry follows. The discussion is restricted to steam turbine cycles of fossil or nuclear power plants, although some ECC's can be employed to a wider range of applications, such as analysis of different heat sources...

Menuchin, Y.; Singh, K. P.; Hirota, N.

1981-01-01T23:59:59.000Z

145

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

E-Print Network (OSTI)

to demonstrate the application of the methodology of rate estimation proposed. Fluid flow rates for steady and transient cases were successfully estimated within engineering accuracy for all three cases. In all three cases, in addition to the traditional downhole...

Hashmi, Gibran Mushtaq

2014-07-08T23:59:59.000Z

146

7-122 A solar pond power plant operates by absorbing heat from the hot region near the bottom, and rejecting waste heat to the cold region near the top. The maximum thermal efficiency that the power plant  

E-Print Network (OSTI)

calculated above. 7-123 A Carnot heat engine cycle is executed in a closed system with a fixed mass of steam can have is to be determined. Analysis The highest thermal efficiency a heat engine operating between transfer. Therefore, the maximum efficiency of the actual heat engine will be lower than the value

Bahrami, Majid

147

Annual Operating Characteristics of Solar Central Water Heater System Assisted by Heat Pump  

Science Journals Connector (OSTI)

The solar central water heater (SCWH) could supply ... massive users effectively and reliably. A SCWH assisted by heat pump (SCWHP) was proposed...

Wei Hu; Zhaolin Gu; Shiyu Feng; Xiufeng Gao

2009-01-01T23:59:59.000Z

148

Measured Performance and Analysis of Ground Source Heat Pumps for Space Conditioning and for Water Heating in a Low-Energy Test House Operated under Simulated Occupancy Conditions  

SciTech Connect

In this paper we present measured performance and efficiency metrics of Ground Source Heat Pumps (GSHPs) for space conditioning and for water heating connected to a horizontal ground heat exchanger (GHX) loop. The units were installed in a 345m2 (3700ft2) high-efficiency test house built with structural insulated panels (SIPs), operated under simulated occupancy conditions, and located in Oak Ridge, Tennessee (USA) in US Climate Zone 4 . The paper describes distinctive features of the building envelope, ground loop, and equipment, and provides detailed monthly performance of the GSHP system. Space conditioning needs of the house were completely satisfied by a nominal 2-ton (7.0 kW) water-to-air GSHP (WA-GSHP) unit with almost no auxiliary heat usage. Recommendations for further improvement through engineering design changes are identified. The comprehensive set of data and analyses demonstrate the feasibility and practicality of GSHPs in residential applications and their potential to help achieve source energy and greenhouse gas emission reduction targets set under the IECC 2012 Standard.

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

2012-01-01T23:59:59.000Z

149

RATES  

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

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

150

RATES  

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

Marketing > RATES Marketing > RATES RATES Current Rates Past Rates 2006 2007 2008 2009 2010 2011 2012 Rates Schedules Power CV-F13 CPP-2 Transmissions CV-T3 CV-NWT5 PACI-T3 COTP-T3 CV-TPT7 CV-UUP1 Ancillary CV-RFS4 CV-SPR4 CV-SUR4 CV-EID4 CV-GID1 Future and Other Rates SNR Variable Resource Scheduling Charge FY12-FY16 (October 1, 2012) SNR Rates Process Calendar (PDF - 171K) Procedures Informal Process Transmission Action Items List (PDF - 144K) Power Action Item List updated on 4-27-10 (PDF - 155K) Power Action Item List (Quick links to relevant documents) Formal Process Rates Brochure (01/11/2011) (PDF - 900K) Appendix A - Federal Register Notice (01/03/2011) (PDF - 8000K) Appendix B - Central Valley Project Power Repayment Study (PDF - 22,322K) Appendix C - Development of the CVP Cost of Service Study (PDF - 2038K)

151

Radiation source rate estimation through data assimilation of gamma dose rate measurements for operational nuclear emergency response systems  

Science Journals Connector (OSTI)

This paper presents an evaluation of an innovative data assimilation method that has been recently developed in NCSR Demokritos for estimating an unknown emission rate of radionuclides in the atmosphere, with real-scale experimental data. The efficient algorithm is based on the assimilation of gamma dose rate measured data in the Lagrangian atmospheric dispersion model DIPCOT and uses variational principles. The DIPCOT model is used in the framework of the nuclear emergency response system (ERS) RODOS. The evaluation is performed by computational simulations of dispersion of Ar-41 that was emitted routinely by the Australian Nuclear Science and Technology Organisation's (ANSTO) previous research reactor, HIFAR, located in Sydney, Australia. In this paper the algorithm is evaluated against a more complicated case than the others used in previous studies: there was only one monitoring station available each day and the site topography is characterised as moderately complex. Overall the estimated release rate approaches the real one to a very satisfactory degree as revealed by the statistical indicators of errors.

Vasiliki Tsiouri; Spyros Andronopoulos; Ivan Kovalets; Leisa L. Dyer; John G. Bartzis

2012-01-01T23:59:59.000Z

152

Comparison between a spray column and a sieve tray column operating as liquid-liquid heat exchangers  

SciTech Connect

The performance of a spray column and a sieve tray column was compared as a liquid-liquid heat exchanger. In carrying out these studies a 15.2 cm (6.0 in.) diameter column, 183 cm (6.0 ft) tall was utilized. The performance of the spray column as a heat exchanger was shown to correlate with the model of Letan-Kehat which has as a basis that the heat transfer is dominated by the wakeshedding characteristics of the drops over much of the column length. This model defines several hydrodynamic zones along the column of which the wake formation zone at the bottom appears to have the most efficient heat transfer. The column was also operated with four perforated plates spaced two column diameters apart in order to take advantage of the wake formation zone heat transfer. The plates induce coalescence of the dispersed phase and reformation of the drops, and thus cause a repetition of the wake formation zone. It is shown that the overall volumetric heat transfer coefficient in a perforated plate column is increased by a minimum of eleven percent over that in a spray column. A hydrodynamic model that predicts the performance of a perforated plate column is suggested.

Keller, A.; Jacobs, H.R.; Boehm, R.F.

1980-12-01T23:59:59.000Z

153

Cooling energy efficiency and classroom air environment of a school building operated by the heat recovery air conditioning unit  

Science Journals Connector (OSTI)

Abstract The recently-built school buildings have adopted novel heat recovery ventilator and air conditioning system. Heat recovery efficiency of the heat recovery facility and energy conservation ratio of the air conditioning unit were analytically modeled, taking the ventilation networks into account. Following that, school classroom displacement ventilation and its thermal stratification and indoor air quality indicated by the CO2 concentration have been numerically modeled concerning the effects of delivering ventilation flow rate and supplying air temperature. Numerical results indicate that the promotion of mechanical ventilation rate can simultaneously boost the dilution of indoor air pollutants and the non-uniformity of indoor thermal and pollutant distributions. Subsequent energy performance analysis demonstrates that classroom energy demands for ventilation and cooling could be reduced with the promotion of heat recovery efficiency of the ventilation facility, and the energy conservation ratio of the air conditioning unit decreases with the increasing temperatures of supplying air. Fitting correlations of heat recovery ventilation and cooling energy conservation have been presented.

Yang Wang; Fu-Yun Zhao; Jens Kuckelkorn; Di Liu; Li-Qun Liu; Xiao-Chuan Pan

2014-01-01T23:59:59.000Z

154

RATES  

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

RATES RATES Rates Document Library SNR Rates Process Calendar (PDF - 171K) Procedures Informal Process Transmission Action Items List (PDF - 144K) Power Action Item List updated on 4-27-10 (PDF - 155K) Power Action Item List (Quick links to relevant documents) Formal Process Rates Brochure (01/11/2011) (PDF - 900K) Appendix A - Federal Register Notice (01/03/2011) (PDF - 8000K) Appendix B - Central Valley Project Power Repayment Study (PDF - 22,322K) Appendix C - Development of the CVP Cost of Service Study (PDF - 2038K) Appendix D - Western Transmission System Facilities Map (PDF - 274K) Appendix E - Estimated FY12 FP and BR Customer (PDF - 1144K) Appendix F - Forecasted Replacements and Additions FY11 - FY16 (PDF - 491K) Appendix G - Definitions (PDF - 1758K) Appendix H - Acronyms (PDF - 720K)

155

Design and Operational Planning of Energy Networks Based on Combined Heat and Power Units  

Science Journals Connector (OSTI)

For each time period and sector, big-M constraints 13 model the heat (generated by the energy generator installed in the sector) transferred to the heat storage tank of the sector (Q?sit). ... Heat and electricity demand data for the reference case have been taken from the Milton Keynes Energy Park data set provided by the U.K. Energy Research Centre Energy Data Centre. ... Cardoso, G.; Stadler, M.; Siddiqui, A.; Marnay, C.; Deforest, N.; Barbosa-Pvoa, A.; Ferro, P.Microgrid reliability modeling and battery scheduling using stochastic linear programming Electric Power Syst. ...

Nikolaos E. Koltsaklis; Georgios M. Kopanos; Michael C. Georgiadis

2014-03-05T23:59:59.000Z

156

Understanding the operation and use of high temperature electrochemical corrosion rate probes  

SciTech Connect

Electrochemical corrosion rate probes were constructed and tested along with mass loss coupons in a N2/O2/CO2 plus water vapor environment. Temperatures ranged from 450 to 600 C. Corrosion rates for ash-covered mild steel, 304L SS, and 316L SS probes using electrochemical techniques were a function of time, temperature, and process environment. Correlation between electrochemical and mass loss corrosion rates was good.

Covino, Bernard S., Jr.; Bullard, Sophie J.; Cramer, Stephen D.; Holcomb, Gordon R.; Ziomek-Moroz, M.; Cayard, Michael S. (InterCorr International Inc.); Eden, David A. (InterCorr International Inc.)

2004-01-01T23:59:59.000Z

157

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

SciTech Connect

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

George A. Young; Nathan Lewis

2003-04-05T23:59:59.000Z

158

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

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

159

Improving central heating plant performance at the defense construction supply center (DCSC): Advanced operation and maintenance methods. Final report  

SciTech Connect

A 1987 air pollution emissions test done by the U.S. Army Environmental Hygiene Agency (USAEHA) identified several problems with the central heating plant (CHP) at the Defense Construction Supply Center (DCSC), Columbus, OH. Though DCSC repaired the specified problems, improved coal specifications, and tried to reduce air infiltration, CHP performance remained at unacceptable levels. Consequently, DCSC contracted the U.S. Army Construction Engineering Research Laboratories (USACERL) to apply advanced operation and maintenance procedures to improve its combustion system. This study employed a system-wide approach to evaluate the CHP 5 fuel storage, combustion, heat distribution, and the control of air emissions. Many short-term improvements to the CHP were identified and tested. Subsequent combustion and air emissions tests revealed that the recommended improvements successfully increased CHP efficiency. Long-term improvements were also recommended to help maintain the short-term improvements.

Savoie, M.J.; Standerfer, J.; Schmidt, C.M.; Gostich, J.; Mignacca, J.

1994-11-01T23:59:59.000Z

160

Fact #659: January 24, 2011 Fuel Economy Ratings for Vehicles Operating on Electricity  

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

The Environmental Protection Agency has developed a new methodology for determining how fuel economy information will be displayed on the window sticker of a vehicle that operates on electricity....

Note: This page contains sample records for the topic "operating heat rate" 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

Method and apparatus for operating a self-starting air heating system  

DOE Patents (OSTI)

A self-starting, fuel fired, air heating system including a fuel burner fired 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 and heating the air. Also, a condensate pump is driven by the turbine. The disclosure is particularly concerned with a method and apparatus which on start-up prevents the vapor generator's vapor output from being conducted to the turbine until a predetermined pressure differential has been achieved. However, after the vapor flow is once permitted, it cannot again be prevented until after the fuel burner has been shut off and restarted.

Heinrich, Charles E. (Mentor, OH)

1983-12-06T23:59:59.000Z

162

Thermionic converter with differentially heated cesium-oxygen source and method of operation  

SciTech Connect

A thermionic converter having an emitter, a collector, and a source of cesium vapor is provided wherein the source of cesium vapor is differentially heated so that said source has a hotter end and a cooler end, with cesium vapor evaporating from said hotter end into the space between the emitter and the collector and with cesium vapor condensing at said cooler end. The condensed cesium vapor migrates through a porous element from the cooler end to the hotter end.

Rasor, Ned S. (Cupertino, CA); Riley, David R. (West Newton, PA); Murray, Christopher S. (Bethel Park, PA); Geller, Clint B. (Pittsburgh, PA)

2000-01-01T23:59:59.000Z

163

Thermionic converter with differentially heated cesium-oxygen source and method of operation  

SciTech Connect

A thermionic converter having an emitter, a collector, and a source of cesium vapor is provided, wherein the source of cesium vapor is differentially heated so that said source has a hotter end and a cooler end, with cesium vapor evaporating from said hotter end into the space between the emitter and the collector and with cesium vapor condensing at said cooler end. The condensed cesium vapor migrates through a porous element from the cooler end to the hotter end.

Rasor, N.S.; Riley, D.R.; Murray, C.S.; Geller, C.B.

1998-12-01T23:59:59.000Z

164

Exponential quadratic operators and evolution of bosonic systems coupled to a heat bath  

SciTech Connect

Using exponential quadratic operators, we present a general framework for studying the exact dynamics of system-bath interaction in which the Hamiltonian is described by the quadratic form of bosonic operators. To demonstrate the versatility of the approach, we study how the environment affects the squeezing of quadrature components of the system. We further propose that the squeezing can be enhanced when parity kicks are applied to the system.

Ni Xiaotong [Department of Physics and the Key Laboratory of Atomic and Nanosciences, Ministry of Education, Tsinghua University, Beijing 100084 (China); Liu Yuxi [Institute of Microelectronics, Tsinghua University, Beijing 100084 (China); Tsinghua National Laboratory for Information Science and Technology, Tsinghua University, Beijing 100084 (China); Kwek, L. C. [Center for Quantum Technologies, National University of Singapore, 2 Science Drive 3, Singapore 117542, Singapore and National Institute of Education and Institute of Advanced Studies, Nanyang Technological University, 1 Nanyang Walk, Singapore 637616 (Singapore); Wang Xiangbin [Department of Physics and the Key Laboratory of Atomic and Nanosciences, Ministry of Education, Tsinghua University, Beijing 100084 (China); Tsinghua National Laboratory for Information Science and Technology, Tsinghua University, Beijing 100084 (China)

2010-06-15T23:59:59.000Z

165

ICRF heating at JET: From operations with a metallic wall to the long term perspective of a DT campaign  

SciTech Connect

The first series of experiments with the ITER-like wall (ILW) will start mid-2011 with D plasmas and will continue through 2012-13 with H, {sup 4}He and D plasmas, and up to 2014-15, when a DT campaign is proposed. In this paper, the previous experience at JET is reviewed to set the scene for the future challenges of ICRF operation including change in the ICRF coupling, W impurity production and evaluation of localized power loads due the RF sheaths. development in a Beryllium/Tungsten environment of ICRF heating schemes for the non activated and the DT phases of ITER.

Mayoral, M.-L.; Graham, M.; Jacquet, Ph.; Monakhov, I.; Riccardo, V. [Euratom/CCFE Fusion Association, Culham Science Centre, OX14 3DB (United Kingdom); Colas, L. [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Eriksson, L.-G. [European Commission, Brussels, B-1049 (Belgium); Lerche, E.; Van Eester, D. [LPP-ERM/KMS, Association Euratom-'Belgian State' (Belgium)

2011-12-23T23:59:59.000Z

166

RELAP5/MOD3 simulation of the loss of residual heat removal during midloop operation experiment conducted at the ROSA-IV/ Large Scale Test Facility  

E-Print Network (OSTI)

The modeling of the complex thermal hydraulics Of reactor systems involves the use Of experimental test systems as well as numerical codes. A simulation of the loss of residual heat removal (RHR) during midloop operations was performed using...

Banerjee, Sibashis Sanatkumar

2012-06-07T23:59:59.000Z

167

Fluid Bed Waste Heat Boiler Operating Experience in Dirty Gas Streams  

E-Print Network (OSTI)

from 13 to 15 million BTU per hour for fired boiler efficiencies of 80% to 70% respectively. The savings represents 85 to 90% of the energy entering the waste heat boiler. Equiva lent furnace efficiency increases from 25% to over 60% on high fire... Fired Boiler Efficiency 0.70 0.75 0.80 Energy Savings Furnace Efficiency Corresponding Peak Fuel Equivalent at High (1) . Savi ngs Fire on Melt 4453 kw (15.1x10 6 BTU/hr) 69% 4156 kw (14.1x10 6 BTU/hr) 66% 3896 kw (13.3x10 6 BTU/hr) 63% (1...

Kreeger, A. H.

168

Topic 14. Retrofit and optimal operation of the building energy systems Performances of Low Temperature Radiant Heating Systems  

E-Print Network (OSTI)

panel system are given by its energy (the consumption of gas for heating, electricity for pumps Temperature Radiant Heating Systems Milorad Boji1*, Dragan Cvetkovi1 , Jasmina Skerli1 , Danijela Nikoli1, wall heating, floor heating, ceiling heating, EnergyPlus SUMMARY Low temperature heating panel systems

Paris-Sud XI, Université de

169

Development of thermoacoustic engine operating by waste heat from cooking stove  

Science Journals Connector (OSTI)

There are about 1.5 billion people worldwide use biomass as their primary form of energy in household cooking[1]. They do not have access to electricity and are too remote to benefit from grid electrical supply. In many rural communities stoves are made without technical advancements mostly using open fires cooking stoves which have been proven to be extremely low efficiency and about 93% of the energy generated is lost during cooking. The cooking is done inside a dwelling and creates significant health hazard to the family members and pollution to environment. SCORE (www.score.uk.com) is an international collaboration research project to design and build a low-cost high efficiency woodstove that uses about half amount of the wood of an open wood fire and uses the waste heat of the stove to power a thermoacoustic engine (TAE) to produce electricity for applications such as LED lighting charging mobile phones or charging a 12V battery. This paper reviews on the development of two types of the thermoacoustic engine powered by waste heat from cooking stove which is either using Propane gas or burning of wood as a cooking energy to produce an acceptable amount of electricity for the use of rural communities.

2012-01-01T23:59:59.000Z

170

Coal flow aids reduce coke plant operating costs and improve production rates  

SciTech Connect

Chemical coal flow aids can provide many benefits to coke plants, including improved production rates, reduced maintenance and lower cleaning costs. This article discusses the mechanisms by which coal flow aids function and analyzes several successful case histories. 2 refs., 10 figs., 1 tab.

Bedard, R.A.; Bradacs, D.J.; Kluck, R.W.; Roe, D.C.; Ventresca, B.P.

2005-06-01T23:59:59.000Z

171

Seed priming of native ornamental species to improve the rate and uniformity of germination in modern greenhouse operations  

E-Print Network (OSTI)

SEED PRIMING OF NATIVE ORNAMENTAL SPECIES TO IMPROVE THE RATE AND UNIFORMITY OF GERMINATION IN MODERN GREENHOUSE OPERATIONS A Thesis by TERRY LEE FINN ERTY Submitted to the Office of Graduate Studies of Texas A&M University in partial... production efficiency of perennials in commercial greenhouses; and (3) to determine if priming could be used to bypass the stratification requirements of seeds of three Aquilegia species. Priming Lupinus texensis seeds, scarified or nonscarified, in salt...

Finnerty, Terry Lee

2012-06-07T23:59:59.000Z

172

Operation and performance of a 350 kW (100 RT) single-effect/double-lift absorption chiller in a district heating network  

SciTech Connect

The efficiency of combined heat, power, and cold production in total energy systems could be improved significantly if absorption chillers were available that could be driven with limited mass flows of low-temperature hot water. In the case of district heat-driven air conditioning, for example, currently available standard absorption chillers are often not applied because they cannot provide the low hot water return temperature and the specific cooling capacity per unit hot water mass flow that are required by many district heating networks. Above all, a drastic increase in the size of the machine (total heat exchanger area) due to low driving temperature differences if of concern in low-temperature applications. A new type of multistage lithium bromide/water absorption chiller has been developed for the summertime operating conditions of district heating networks. It provides large cooling of the district heating water (some 30 K) and large cooling capacity per unit hot water mass flow. Two pilot plants of this novel absorption chiller were designed within the framework of a joint project sponsored by the German Federal Ministry of Education, Science, Research and Technology (BMBF), a consortium of 15 district heating utilities, and two manufacturers. The plants have been operated since summer 1996 in the district heating networks of Berlin and Duesseldorf. This paper describes the concept, installation, and control strategy of the two pilot plants, and it surveys the performance and operating experience of the plants under varying practical conditions.

Schweigler, C.J.; Preissner, M.; Demmel, S.; Hellmann, H.M.; Ziegler, F.F. [ZAE Bayern, Garching/Munich (Germany)

1998-10-01T23:59:59.000Z

173

Commissioning Process and Operational Improvement in the District Heating and Cooling-APCBC  

E-Print Network (OSTI)

-09-25 Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014 18 Energy simulation In case of the variable cooling water flow system, the cooling water outlet temperature should be a parameter...,000 5,000 6,000 7,000 8,000 9,000 10,000 11,000 12,000 13,000 2012/10/072012/10/28 2012/11/18 2012/12/09 2012/12/30 2/24 ? 3/2 C o n su m ed e le ct ri ci ty p er h ea t u n it [ k W h /G J ] Variable water flow control Cooling tower fun Chilled...

Takase,T.; Takada,O; Shima,K.; Moriya, M.; Shimoda,Y.

2014-01-01T23:59:59.000Z

174

Rational analysis of mass, momentum, and heat transfer phenomena in liquid storage tanks under realistic operating conditions: 1. Basic formulation  

SciTech Connect

This paper presents a computer code that analyses the performance of storage tanks using water as the working fluid. The new aspects of the authors work include the following items: (a) the transient Navier-Stokes equations are expressed in two-dimensional Cartesian and cylindrical coordinates, under the assumption of the Boussinesq approximation, (b) the effective viscosity and thermal diffusivity are evaluated by using a simplified form of the Deardorff turbulence model, (c) the energy equation is solved over a domain which includes the tank and a large portion of the surrounding soil, (d) some properly defined source terms have been introduced in the governing equations to describe inlet/outlet devices inside the tank, and localized friction losses, and (e) the boundary conditions are time-dependent to correctly describe the daily heat exchanges between tank, solar collectors and heat pumps for space conditioning. The Finite Differences (FD) technique and an improved formulation of the Marker and Cell (MAC) method are used to solve the conservation equations. Comparisons with literature studies indicate discrepancies between 0.02 and 0.5%. The results of several tests simulating realistic operating conditions will be shown in the second part of the paper.

Parrini, F.; Vitale, S.; Alabiso, M. (ENEL-Italian National Electricity Board-CRTN, Milan (Italy)); Castellano, L. (MATEC S.r.l., Milan (Italy))

1992-08-01T23:59:59.000Z

175

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

E-Print Network (OSTI)

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

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

2014-07-23T23:59:59.000Z

176

Calculation of single-beam two-photon absorption rate of lanthanides: Effective operator method and perturbative expansion  

SciTech Connect

Perturbative contributions to single-beam two-photon transition rates may be divided into two types. The first, involving low-energy intermediate states, require a high-order perturbation treatment, or an exact diagonalization. The other, involving high-energy intermediate states, only require a low-order perturbation treatment. We show how to partition the effective transition operator into two terms, corresponding to these two types, in such a way that a many-body perturbation expansion may be generated that obeys the linked cluster theorem and has a simple diagrammatic representation.

Duan, C.-K.; Ruan Gang; Reid, Michael F. [Institute of Applied Physics and College of Electronic Engineering, Chongqing University of Post and Telecommunications, Chongqing 400065 (China); Department of Physics and Astronomy, University of Canterbury, Christchurch (New Zealand); Institute of Applied Physics and College of Electronic Engineering, Chongqing University of Post and Telecommunications, Chongqing 400065 (China); Department of Physics and Astronomy and MacDiarmid Institute of Advanced Materials and Nanotechnology, University of Canterbury, Christchurch (New Zealand)

2004-11-01T23:59:59.000Z

177

Heat storage with CREDA  

SciTech Connect

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

178

Diabatic Heating and Cooling Rates Derived from In Situ Microphysics Measurements: A Case Study of a Wintertime U.K. Cold Front  

Science Journals Connector (OSTI)

In situ measurements associated with the passage of a kata cold front over the United Kingdom on 29 November 2011 are used to initialize a Lagrangian parcel model for the purpose of calculating rates of diabatic heating and cooling associated with ...

C. Dearden; P. J. Connolly; G. Lloyd; J. Crosier; K. N. Bower; T. W. Choularton; G. Vaughan

2014-09-01T23:59:59.000Z

179

Heat transfer and heat exchangers reference handbook  

SciTech Connect

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

Not Available

1991-01-15T23:59:59.000Z

180

A Modified Analytical Method for Simulating Cyclic Operation of Vertical U-Tube Ground-Coupled Heat Pumps  

E-Print Network (OSTI)

A modified analytical model is presented which discretizes the ground-coupled heat exchanger of a ground-coupled heat pump and utilized a separate cylindrical source solution for each element. First law expressions are utilized for each element...

Dobson, M. K.; O'Neal, D. L.; Aldred, W.

1994-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "operating heat rate" 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

A DISTILLATION PLANT WITH AN INDIRECT HEAT PUMP FOR EXPERIMENTAL STUDIES OF OPERATION FORM, DYNAMICS AND CONTROL  

Science Journals Connector (OSTI)

ABSTRACT A 19 sieve tray pilot plant distillation column has been designed and erected at Instituttet for Kemiteknik, The Technical University of Denmark. The plant utilizes a heat pump to recirculate the energy from the condenser to the reboiler. The column is equipped with exchangeable trays, in order to be run in either a conventional continuous or a periodic cycling mode. The purpose of the process system is to perform: Control studies of conventional continuous distillation and of periodic cycling distillation. Comparative studies of the two operation forms with respect to separation efficiency and energy efficiency. Two types of distillation separations will be investigated: First a binary distillation using methanol and isopropanol, with the primary purpose of evaluating the properties of the separation process, using a thermodynamically simple system. Later an azeotropic distillation separating isopropanol and water using toluen as entrainer. This system is used as an example of a thermodynamically more demanding distillation. In this paper the the column and heatpump set-up is described and results from steady state and transient experiments are shown and discussed.

L. Hallager; B. Toftegrd; K. Clement; S.B. Jrgensen

1988-01-01T23:59:59.000Z

182

Doubly Fed Induction Generator in an Offshore Wind Power Plant Operated at Rated V/Hz: Preprint  

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

Doubly Fed Induction Generator Doubly Fed Induction Generator in an Offshore Wind Power Plant Operated at Rated V/Hz Preprint Eduard Muljadi, Mohit Singh, and Vahan Gevorgian To be presented at the IEEE Energy Conversion Congress and Exhibition Raleigh, North Carolina September 15-20, 2012 Conference Paper NREL/CP-5500-55573 June 2012 NOTICE The submitted manuscript has been offered by an employee of the Alliance for Sustainable Energy, LLC (Alliance), a contractor of the US Government under Contract No. DE-AC36-08GO28308. Accordingly, the US Government and Alliance retain a nonexclusive royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for US Government purposes. This report was prepared as an account of work sponsored by an agency of the United States government.

183

Mechanism of heat-modification inside a glass after irradiation with high-repetition rate femtosecond laser pulses  

SciTech Connect

Accumulation of thermal energies by highly repeated irradiation of femtosecond laser pulses inside a glass induces the heat-modification whose volume is much larger than that of the photoexcited region. It has been proposed that the heat-modification occurs in the region in which the temperature had overcome a threshold temperature during exposure of laser pulses. In order to understand the mechanism of the heat-modification, we investigated the temperature distribution during laser exposure and the threshold temperature by analyzing the volume of the modification based on a thermal diffusion model. We found that the threshold temperature becomes lower with increasing laser exposure time. The dependence of the threshold temperature on the laser exposure time was explained by the deformation mechanism based on the temperature-dependent viscosity and viscoelastic behavior of a glass under a stress loading by thermal expansion. The deformation mechanism also could simulate a tear-drop shape of a heat-modification by simultaneous double-beams' irradiation and the distribution of birefringence in a heat-modification. The mechanism proposed in this study means that the temperature-dependence of the viscosity of a glass should be essential for predicting and controlling the heat-modification.

Shimizu, Masahiro; Miura, Kiyotaka; Hirao, Kazuyuki [Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510 (Japan); Sakakura, Masaaki; Shimotsuma, Yasuhiko [Innovative Collaboration Center, Kyoto University, Kyoto 615-8520 (Japan); Ohnishi, Masatoshi [Qualtec Co., Ltd., 4-230 Sanbocho, Sakai-ku, Sakai-shi, Osaka 590-0906 (Japan); Nakaya, Takayuki [NJC Institute of Technology, Namiki Precision Jewel Co., Ltd., 8-22 Shinden 3-Chome, Adachi-ku, Tokyo 123-8511 (Japan)

2010-10-15T23:59:59.000Z

184

ANEMOS: A computer code to estimate air concentrations and ground deposition rates for atmospheric nuclides emitted from multiple operating sources  

SciTech Connect

This code estimates concentrations in air and ground deposition rates for Atmospheric Nuclides Emitted from Multiple Operating Sources. ANEMOS is one component of an integrated Computerized Radiological Risk Investigation System (CRRIS) developed for the US Environmental Protection Agency (EPA) for use in performing radiological assessments and in developing radiation standards. The concentrations and deposition rates calculated by ANEMOS are used in subsequent portions of the CRRIS for estimating doses and risks to man. The calculations made in ANEMOS are based on the use of a straight-line Gaussian plume atmospheric dispersion model with both dry and wet deposition parameter options. The code will accommodate a ground-level or elevated point and area source or windblown source. Adjustments may be made during the calculations for surface roughness, building wake effects, terrain height, wind speed at the height of release, the variation in plume rise as a function of downwind distance, and the in-growth and decay of daughter products in the plume as it travels downwind. ANEMOS can also accommodate multiple particle sizes and clearance classes, and it may be used to calculate the dose from a finite plume of gamma-ray-emitting radionuclides passing overhead. The output of this code is presented for 16 sectors of a circular grid. ANEMOS can calculate both the sector-average concentrations and deposition rates at a given set of downwind distances in each sector and the average of these quantities over an area within each sector bounded by two successive downwind distances. ANEMOS is designed to be used primarily for continuous, long-term radionuclide releases. This report describes the models used in the code, their computer implementation, the uncertainty associated with their use, and the use of ANEMOS in conjunction with other codes in the CRRIS. A listing of the code is included in Appendix C.

Miller, C.W.; Sjoreen, A.L.; Begovich, C.L.; Hermann, O.W.

1986-11-01T23:59:59.000Z

185

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

186

Heat Flux Calculation and Problem of Flaking of Boron Carbide Coatings on the Faraday Screen of the ICRH Antennas During Tore Supra High Power, Long Pulse Operation  

SciTech Connect

Reliable and repetitive high power and long pulse tokamak operation is strongly dependant of the ability to secure the Plasma Facing Components (PFCs). In Tore Supra, a network of 7 infrared (IR) video cameras is routinely used to prevent PFCs overheating and damage in selected regions. Real time feedback control and offline analysis are essential for basic protection and understanding of abnormal thermal events. One important limitation detected by the IR real time feed-back loop during high power RF operation (injected power of 9.5 MW over 26 s and 12 MW over 10 s have been achieved respectively in 2006 and 2008) is due to the interaction between fast ions which increase the power flux density and flaking of the boron carbide coatings on the Faraday screen box of the ICRH antennas. An IR-based experimental procedure is proposed in order to detect new flakes during plasma operation. The thermal response of the B4C coating is studied with and without flaking during plasma operation. The experimental heat flux deposited by fast ion losses on the Faraday screen is calculated for high (3.8 T) and low magnetic field (2 T) during high RF power operation (with fundamental hydrogen minority and second harmonic ICRH heating schemes respectively). The paper addresses both thermal science issues applied to machine protection and limitation due to fast ions issues during high RF power, long pulse operation. Safety margin to critical heat flux and number of fatigue cycles under heat load are presented in the paper.

Corre, Y. [French Atomic Energy Commission (CEA), Cadarache, St. Paul lez Durance] [French Atomic Energy Commission (CEA), Cadarache, St. Paul lez Durance; Lipa, M. [CEA IRFM, St. Paul-lez-Durance, France] [CEA IRFM, St. Paul-lez-Durance, France; Agarici, G. [Fusion for Energy (F4E), Barcelona, Spain] [Fusion for Energy (F4E), Barcelona, Spain; Basiuk, V. [CEA IRFM, St. Paul-lez-Durance, France] [CEA IRFM, St. Paul-lez-Durance, France; Colas, L. [French Atomic Energy Commission (CEA)] [French Atomic Energy Commission (CEA); Courtois, X. [CEA, St. Paul Les Durance, France] [CEA, St. Paul Les Durance, France; Dumont, R. J. [French Atomic Energy Commission (CEA), Cadarache, St. Paul lez Durance] [French Atomic Energy Commission (CEA), Cadarache, St. Paul lez Durance; Ekedahl, A. [French Atomic Energy Commission (CEA), Institute for Magnetic Fusion Research (IRFM)] [French Atomic Energy Commission (CEA), Institute for Magnetic Fusion Research (IRFM); Gardarein, J. L. [University of Aix, Marseille, France] [University of Aix, Marseille, France; Klepper, C Christopher [ORNL] [ORNL; Martin, V. [French Atomic Energy Commission (CEA), Institute for Magnetic Fusion Research (IRFM)] [French Atomic Energy Commission (CEA), Institute for Magnetic Fusion Research (IRFM); Moncada, V. [CEA, St. Paul Les Durance, France] [CEA, St. Paul Les Durance, France; Portafaix, C. [CEA, St. Paul Les Durance, France] [CEA, St. Paul Les Durance, France; Rigollet, F. [University of Aix, Marseille, France] [University of Aix, Marseille, France; Tawizgant, R. [CEA, St. Paul Les Durance, France] [CEA, St. Paul Les Durance, France; Travere, J. M. [CEA, St. Paul Les Durance, France] [CEA, St. Paul Les Durance, France; Valliez, K. [CEA, St. Paul Les Durance, France] [CEA, St. Paul Les Durance, France

2011-01-01T23:59:59.000Z

187

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

E-Print Network (OSTI)

DETERMINATION OF THERMAL-DEGRADATION RATES OF SOME CANDIDATE RANKINE-CYCLE ORGANIC WORKING FLUIDS FOR CONVERSION OF INDUSTRIAL WASTE HEAT INTO POWER Mohan L. Jain, Jack Demirgian, John L. Krazinski, and H. Bushby Argonne National Laboratory..., Argonne, Illinois Howard Mattes and John Purcell U.S. Department of Energy ABSTRACT Serious concerns over the long-term thermal In a previous study [1] based on systems stability of organic working fluids and its effect analysis and covering...

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

1984-01-01T23:59:59.000Z

188

Four-mode Bose-Hubbard model with two greatly differing tunneling rates as a model for the Josephson oscillation of heat  

SciTech Connect

As a model for mesoscopic quantum systems in thermal contact, we consider a four-mode Bose-Hubbard model with two greatly differing tunneling rates. By a series of Holstein-Primakoff transformations, we show that the low-frequency dynamics of this system consists in general of two slow Josephson oscillations, rather than the single slow mode predicted by linear Bogoliubov theory. We identify the second slow Josephson oscillation as a heat exchange mode analogous to second sound.

Strzys, M. P.; Anglin, J. R. [OPTIMAS Research Center and Fachbereich Physik, Technische Universitaet Kaiserslautern, D-67653 Kaiserslautern (Germany)

2010-04-15T23:59:59.000Z

189

Design of chemical reactors of the heat exchanger type  

E-Print Network (OSTI)

Operating Profile - Example I 23 , 53 Heat Rate Comparison - Example I Operating Profile - Example 2 Operating Profile - Example 3 Operating Profile - Example 4 Equations (113) and (114) at 790 Reactor Profile - Exan piss 5 and 6 Heat of Reaction.... simple inathematical function of time. While his work was a step forward, it is not directly applicable to the problem of reactor design. Hougen and Watsor. (3), and recently Fair and Rase (4), illustra- ted an exact non-machine method of reactor...

McBeth, Lloyd Theodore

2012-06-07T23:59:59.000Z

190

Optimization of the design and mode of operation of a QD laser for reducing the heat-to-bitrate ratio  

SciTech Connect

Heat dissipation under the high-speed modulation of quantum dot edge-emitting lasers is considered. It is shown that, for a given laser diode, there is a bias current at which the heat-to-bitrate ratio is minimized. Moreover, there exists a certain optimal optical loss of the laser cavity at which the lowest heat-to-bitrate ratio is provided for any design of edge-emitting lasers that can be fabricated from an epitaxial structure. The heat-to-bitrate ratio and the corresponding bitrate are numerically calculated and analytical expressions are derived. It is demonstrated that the heat-to-bitrate ratio of quantum dot edge-emitting lasers can be less than 0.4 pJ/bit at a bitrate exceeding 10 Gbit/s.

Zhukov, A. E., E-mail: zhukale@gmail.com; Savelyev, A. V. [Russian Academy of Sciences, St. Petersburg Academic University-Nanotechnology Research and Education Center (Russian Federation)] [Russian Academy of Sciences, St. Petersburg Academic University-Nanotechnology Research and Education Center (Russian Federation); Maximov, M. V. [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)] [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation); Kryzhanovskaya, N. V. [Russian Academy of Sciences, St. Petersburg Academic University-Nanotechnology Research and Education Center (Russian Federation)] [Russian Academy of Sciences, St. Petersburg Academic University-Nanotechnology Research and Education Center (Russian Federation); Gordeev, N. Yu.; Shernyakov, Yu. M. [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)] [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation); Payusov, A. S.; Nadtochiy, A. M.; Zubov, F. I.; Korenev, V. V. [Russian Academy of Sciences, St. Petersburg Academic University-Nanotechnology Research and Education Center (Russian Federation)] [Russian Academy of Sciences, St. Petersburg Academic University-Nanotechnology Research and Education Center (Russian Federation)

2013-08-15T23:59:59.000Z

191

System Modeling of Gas Engine Driven Heat Pump  

SciTech Connect

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

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

2012-01-01T23:59:59.000Z

192

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

E-Print Network (OSTI)

and potential energy changes are zero. 3 Steam properties are used for geothermal water. Properties Using7-31 7-88 A geothermal power plant uses geothermal liquid water at 160ºC at a specified rate saturated liquid properties, the source and the sink state enthalpies of geothermal water are (Table A-4) k

Bahrami, Majid

193

Determination of size-specific U-factors and solar heat gain coefficients from rated values at established sizes -- A simplified approach  

SciTech Connect

Organizations such as the National Fenestration Rating Council (NFRC) in the United States and the Canadian Standards Association in Canada have done a vast amount of work to develop standardized procedures for rating the thermal performance of window systems. These procedures provide an excellent means of comparing one window product to another. One limitation to the use of the information produced in these rating procedures is that the data are produced through measurement or simulation for a fixed window size. To use these data in building energy computer simulations, the U-factor and solar heat gain coefficient (SHGC) data need to be available for the actual window sizes used in a building. The window labeling information provided through the window rating procedures in the US and Canada is not enough to calculate size-specific U-factor or SHGC values. Using minimal information that is provided from the rating procedures and making a few simplifying assumptions will allow for /an approximation of the size-specific U-factor and SHGC values. The work presented in this paper outlines a simplified approach to determining size-specific U-factor and SHGC values.

Baker, J.A. [WestLab, Waterloo, Ontario (Canada); Henry, R. [CANMET/Natural Resources, Ottawa, Ontario (Canada)

1997-12-31T23:59:59.000Z

194

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

SciTech Connect

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

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

2013-05-22T23:59:59.000Z

195

Optimization of automation: I. Estimation method of cognitive automation rates reflecting the effects of automation on human operators in nuclear power plants  

Science Journals Connector (OSTI)

Abstract Since automation was introduced in various industrial fields, the concept of the automation rate has been used to indicate the inclusion proportion of automation among all work processes or facilities. Expressions of the inclusion proportion of automation are predictable, as is the ability to express the degree of the enhancement of human performance. However, many researchers have found that a high automation rate does not guarantee high performance. Therefore, to reflect the effects of automation on human performance, this paper proposes a new estimation method of the automation rate that considers the effects of automation on human operators in nuclear power plants (NPPs). Automation in \\{NPPs\\} can be divided into two types: system automation and cognitive automation. Some general descriptions and characteristics of each type of automation are provided, and the advantages of automation are investigated. The advantages of each type of automation are used as measures of the estimation method of the automation rate. One advantage was found to be a reduction in the number of tasks, and another was a reduction in human cognitive task loads. The system and the cognitive automation rate were proposed as quantitative measures by taking advantage of the aforementioned benefits. To quantify the required human cognitive task loads and thus suggest the cognitive automation rate, Conants information-theory-based model was applied. The validity of the suggested method, especially as regards the cognitive automation rate, was proven by conducting experiments. The result showed that a decreased rate of the operator working time was significantly related to the cognitive automation rate and that the calculation of the cognitive task load was useful as a measure of the cognitive automation rate.

Seung Min Lee; Jong Hyun Kim; Poong Hyun Seong

2014-01-01T23:59:59.000Z

196

Minimal universal quantum heat machine  

E-Print Network (OSTI)

In traditional thermodynamics the Carnot cycle yields the ideal performance bound of heat engines and refrigerators. We propose and analyze a minimal model of a heat machine that can play a similar role in quantum regimes. The minimal model consists of a single two-level system with periodically modulated energy splitting that is permanently, weakly, coupled to two spectrally-separated heat baths at different temperatures. The equation of motion allows to compute the stationary power and heat currents in the machine consistently with the second-law of thermodynamics. This dual-purpose machine can act as either an engine or a refrigerator (heat pump) depending on the modulation rate. In both modes of operation the maximal Carnot efficiency is reached at zero power. We study the conditions for finite-time optimal performance for several variants of the model. Possible realizations of the model are discussed.

David Gelbwaser-Klimovsky; Robert Alicki; Gershon Kurizki

2012-09-06T23:59:59.000Z

197

Project Title: Small Scale Electrical Power Generation from Heat Co-Produced in Geothermal Fluids: Mining Operation  

SciTech Connect

Demonstrate the technical and economic feasibility of small scale power generation from low temperature co-produced fluids. Phase I is to Develop, Design and Test an economically feasible low temperature ORC solution to generate power from lower temperature co-produced geothermal fluids. Phase II &III are to fabricate, test and site a fully operational demonstrator unit on a gold mine working site and operate, remotely monitor and collect data per the DOE recommended data package for one year.

Clark, Thomas M [Principal Investigator; Erlach, Celeste [Communications Mgr.

2014-12-30T23:59:59.000Z

198

Multi-criteria Operation Strategies of Power-to-Heat-Systems in Virtual Power Plants with a High Penetration of Renewable Energies  

Science Journals Connector (OSTI)

Abstract The integration of renewable energy into the existing energy supply system is a core challenge regarding the successful realization of the German Energiewende. One concept to integrate decentralized regenerative power generators is a virtual power plant that operates many small facilities as one power plant. Essential parts of the concept are controllable loads and generators to reduce the impact of volatile energy resource like wind power stations on operational planning. Power-to-Heat-Systems (P2H) are one possible technology that can be used to a limited extent as a controllable load. The P2H-system as a component of virtual power plants is capable of supplying flexibility due to various possible operation strategies. This flexibility can either be used for ancillary services (primary, secondary and tertiary ancillary services), to provide schedule energy or for balancing group management. This paper presents a modeling approach for P2H systems as a component of virtual power plants with a high share of renewable energies. The operation strategies are evaluated with respect to economic and technical aspects and uncertainties in generation and load. The operation strategies of P2H systems are shown with regard to market integration of renewable energies within a virtual power plant and the provision of ancillary services.

Torsten Sowa; Stefan Krengel; Simon Koopmann; Johannes Nowak

2014-01-01T23:59:59.000Z

199

Industrial heat pumps - types and costs  

SciTech Connect

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

200

Results of calculations of external gamma radiation exposure rates from fallout and related radionuclide compositions. Operation Teapot, 1955  

SciTech Connect

This report presents data on calculated gamma radiation exposure rates and ground deposition of related radionuclides resulting from events that deposited detectable radioactivity outside the Nevada Test Site complex.

Hicks, H.G.

1981-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "operating heat rate" 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

Fabric composite heat pipe technology development  

SciTech Connect

Testing has been performed on a variety of fabric composite technology feasibility issues. These include an evaluation of the effective radiation heat transfer rate from a heated metallic surface covered by a ceramic fabric with the intent of determining the effective emissivity'' of the combination of materials, studies of the wicking properties of ceramic fabrics, and the construction of fabric composite heat pipes to test their working properties under both steady state and transient conditions. Results of these experiments shown that fabric composite combinations have greatly enhanced effective emissivities'' resulting from the increases surface area of the fabric, ceramic fabrics can work very well as the wick for heat pipes, ceramic fabric heat pipes have been demonstrated to operate under typical space conditions, and large mass reductions are possible by using fabric composite heat pipes for heat rejection radiator systems.

Klein, A.C.; Gulshan-Ara, Z.; Kiestler, W.; Snuggerud, R.; Marks, T.S. (Department of Nuclear Engineering, Oregon State University, Corvallis, Oregon 97331 (United States))

1993-01-10T23:59:59.000Z

202

Operation of a low temperature absorption chiller at rating point and at reduced evaporator temperature. Final report  

SciTech Connect

The returned SAM 015 (fifteen ton Solar Absorption Machine) chiller was given a cursory visual inspection, some obvious problems were remedied, and then it was placed on a test stand to get a measure of dirty performance. It was then given a standard acid clean, the water side of the tubes was brushed clean, and then the machine was retested. The before and after cleaning data were compared to equivalent data taken before the machine was shipped. The second part of our work statement was to experimentally demonstrate the technical feasibility of operating the chiller at evaporator temperatures below O/sup 0/C (32/sup 0/F) and identify any operational problems.

Best, R.; Biermann, W.; Reimann, R.

1985-01-01T23:59:59.000Z

203

Burning mill sludge in a fluidized-bed incinerator and waste-heat-recovery system; Ten years of successful operation  

SciTech Connect

This paper reports on burning mill sludge in a fluidized-bed incinerator and waste-heat-recovery system. In the late 1970s, the Lielahti sulfite mill of G.A. Serlachius Corp. (now Metsa Serla Oy) began investigating alternative methods of sludge disposal. The mill had an annual capacity of 100,000 tons of bleached pulp, generated 80,000 tons of by-product lignin sulfonates, and specialized in dissolving pulps. Because of the end product's high quality requirements, the mill had a low pulp yield and high losses in the form of both dissolved and suspended solids.

Nickull, O. (Metsa Serla, Oy (FI)); Lehtonen, O. (Tampella Ltd., Tampere (FI)); Mullen, J. (Tampella Keeler, Williamsport, PA (US))

1991-03-01T23:59:59.000Z

204

Two-sided estimates on Dirichlet heat kernels for time-dependent parabolic operators with singular drifts  

E-Print Network (OSTI)

, -domain in Rd , where d 1 and (0, 1]. Our operator is L + µ · x, where L is a time-dependent uniformly Foundation of Korea(NRF) funded by the Ministry of Education, Science and Technology(2011-0009685) 2Panki Kim is supported by Basic Science Research Program through the National Re- search Foundation of Korea(NRF) grant

Kim, Panki

205

Application of microwave heating to ceramic processing: Design and initial operation of a 2.45-GHz single-mode furnace  

SciTech Connect

High-power microwave and millimeter-wave sources are currently being applied to ceramic processing studies at the Naval Research Laboratory (NRL). A single-mode cavity microwave furnace, operating in the TE{sub 103} mode at 2.45 GHz, is operational and is being used to investigate sintering of nanocrystalline ceramics. This paper reports the design of the 2.45-GHz furnace and its use in initial microwave sintering experiments on nanocrystalline alumina and titania compacts. The high purity Al{sub 2}O{sub 3} and TiO{sub 2} nanocrystalline powders used in the sintering experiments were prepared by the sol-gel method. These powders were first uniaxially pressed to 14 MPa, cold isostatically pressed (CIP`ed) to various pressures {ge}420 MPa, and finally sectioned into wafers. The density of the green compacts was 30 to 38% theoretical density (TD). The compacts were placed in insulating fiberboard caskets which were sufficiently lossy to provide hybrid heating at room temperature. The compacts were heated in the microwave furnace for up to three hours at temperatures {ge}1720 C. The temperature of the workpiece was monitored using an optical pyrometer. Final densities up to 80% TD have been obtained to date for Al{sub 2}O{sub 3} and up to 52% TD for TiO{sub 2}. The sintered compacts were characterized by X-ray diffraction and by scanning electron microscopy (SEM) to determine the phase and grain size.

Fliflet, A.W. [Naval Research Lab., Washington, DC (United States)] [Naval Research Lab., Washington, DC (United States); Bruce, R.W.; Kinkead, A.K. [Sachs/Freeman Associates Inc., Landover, MD (United States)] [and others] [Sachs/Freeman Associates Inc., Landover, MD (United States); and others

1996-06-01T23:59:59.000Z

206

Process for heating coal-oil slurries  

DOE Patents (OSTI)

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

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

1984-01-03T23:59:59.000Z

207

Process for heating coal-oil slurries  

DOE Patents (OSTI)

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

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

1984-01-03T23:59:59.000Z

208

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

209

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

210

Microwave heating for adsorbents regeneration and oil sands coke activation.  

E-Print Network (OSTI)

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

Chen, Heng

2010-01-01T23:59:59.000Z

211

Performance Optimization of an Irreversible Heat Pump with Variable-temperature Heat Reservoirs  

E-Print Network (OSTI)

An irreversible cycle model of a heat pump operating between two variable-temperature heat reservoirs is established and used to analyze the performance of the heat pump affected by heat resistances, heat leakage and internal dissipation...

Huang, Y.; Sun, D.

2006-01-01T23:59:59.000Z

212

Rates & Repayment  

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

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

213

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

SciTech Connect

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

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

2013-01-01T23:59:59.000Z

214

Domestic Heating and Thermal Insulation  

Science Journals Connector (OSTI)

... DIGEST 133 of the Building Research Station, entitled "Domestic Heating and Thermal Insulation" (Pp. 7. London : H.M. Stationery Office, 1960. 4insulation, the standard of heating, the ventilation-rate and the length of the heating season ...

1960-09-17T23:59:59.000Z

215

Environmentally Friendly Systems: Earth Heat Pump System with Vertical Pipes for Heat Extraction for Domestic Heating and Cooling  

Science Journals Connector (OSTI)

Geothermal heat pumps (GSHPs), or direct expansion (DX) ground source heat pumps, are highly efficient renewable energy technology, ... the earth, groundwater or surface water as heat sources when operating in heating

Saffa Riffat; Siddig Omer; Abdeen Omer

2014-01-01T23:59:59.000Z

216

The Homopolar Pulse Billet Heating Process  

E-Print Network (OSTI)

The use of homopolar generators operated in the pulse mode to heat forging billets offers several possible advantages over present heating methods. Because heating is uniform throughout the entire cross section, billets can safely be heated...

Keith, R. E.; Weldon, W. F.

1982-01-01T23:59:59.000Z

217

Method of measuring heat influx of a cryogenic transfer system  

DOE Patents (OSTI)

A method is provided for measuring the heat influx of a cryogenic transfer system. A gaseous phase of the cryogen used during normal operation of the system is passed through the system. The gaseous cryogen at the inlet to the system is tempered to duplicate the normal operating temperature of the system inlet. The temperature and mass flow rate of the gaseous cryogen is measured at the outlet of the system, and the heat capacity of the cryogen is determined. The heat influx of the system is then determined from known thermodynamic relationships.

Niemann, Ralph C. (Downers Grove, IL); Zelipsky, Steven A. (Tinley Park, IL); Rezmer, Ronald R. (Lisle, IL); Smelser, Peter (Bruner, MO)

1981-01-01T23:59:59.000Z

218

HEAT RECOVERY FROM WASTE WATER BY MEANS OF A RECUPERATIVE HEAT EXCHANGER AND A HEAT PUMP  

Science Journals Connector (OSTI)

ABSTRACT The useful heat of warm waste water is generally transferred to cold water using a recuperative heat exchanger. Depending on its design, the heat exchanger is able to utilise up to 90% of the waste heat potential available. The electric energy needed to operate such a system is more than compensated for by an approximately 50-fold gain of useful heat. To increase substantially the waste heat potential available and the amount of heat recovered, the system for recuperative heat exchange can be complemented by a heat pump. Such a heat recovery system on the basis of waste water is being operated in a public indoor swimming pool. Here the recuperative heat exchanger accounts for about 60%, the heat pump for about 40% of the toal heat reclaimed. The system consumes only 1 kWh of electric energy to supply 8 kWh of useful heat. In this way the useful heat of 8 kWh is compensated for by the low consumption of primary energy of 2.8 kWh. Due to the installation of an automatic cleaning device, the heat transfer surfaces on the waste water side avoid deposits so that the troublesome maintenance work required in other cases on the heat exchangers is not required. KEYWORDS Shower drain water, recuperative heat recovery, heat recovery by means of a heat pump, combination of both types of heat recovery, automatic cleaning device for the heat exchangers, ratio of useful heat supply vs. electric energy consumption, economic consideration.

K. Biasin; F.D. Heidt

1988-01-01T23:59:59.000Z

219

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

220

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

Note: This page contains sample records for the topic "operating heat rate" 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

A correlated K-distribution model of the heating rates for H[sub 2]O and a molecular mixture in the 0-2500 cm[sup [minus]1] wavelength region in the atmosphere between 0 and 60 km  

SciTech Connect

For this report a prototype infrared radiative transfer model using a correlated k-distribution technique to calculate the transmission between atmospheric levels has been used to calculate the radiative fluxes and heating rates for H[sub 2]O and a mixture of the major molecular absorbers in the atmosphere between 0 and 60 km. The mixture consists of H[sub 2]O, CO[sub 2], O[sub 3], CH[sub 4], and N[sub 2]O. The wave number range considered is 0-2500 cm[sup [minus]1]. The use of the k-distribution method allows 25 cm[sup [minus]1] wave number bins to produce fluxes and heating rates which are within ten percent of the results of detailed line by line calculations.

Grossman, A S; Grant, K E

1992-11-16T23:59:59.000Z

222

Including radiative heat transfer and reaction quenching in modeling a Claus plant waste heat boiler  

SciTech Connect

Due to increasingly stringent sulfur emission regulations, improvements are necessary in the modified Claus process. A recently proposed model by Nasato et al. for the Claus plant waste heat boiler (WHB) is improved by including radiative heat transfer, which yields significant changes in the predicted heat flux and the temperature profile along the WHB tube, leading to a faster quenching of chemical reactions. For the WHB considered, radiation accounts for approximately 20% of the heat transferred by convection alone. More importantly, operating the WHB at a higher gas mass flux is shown to enhance reaction quenching, resulting in a doubling of the predicted hydrogen flow rate. This increase in hydrogen flow rate is sufficient to completely meet the hydrogen requirement of the H[sub 2]S recovery process considered, which would eliminate the need for a hydrogen plant.

Karan, K.; Mehrotra, A.K.; Behie, L.A. (Univ. of Calgary, Alberta (Canada). Dept. of Chemical and Petroleum Engineering)

1994-11-01T23:59:59.000Z

223

Challenge # 3 ? Operational Issues  

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

Potential for a renewable heating oil substitution Challenge 3 - Operational Issues What are the most significant barriers to overcome in each market segment? Fernando Preto The...

224

Flow and heat transfer in porous micro heat sink for thermal management of high power LEDs  

Science Journals Connector (OSTI)

A novel porous micro heat sink system is presented for thermal management of high power LEDs, which has high heat transport capability. The operational principle and heat transfer characteristics of porous micro heat sink are analyzed. Numerical model ... Keywords: Heat dissipation, High heat flux, High power LEDs, Porous media, Porous micro heat sink

Z. M. Wan; J. Liu; K. L. Su; X. H. Hu; S. S. M

2011-05-01T23:59:59.000Z

225

Cab Heating and Cooling  

SciTech Connect

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

Damman, Dennis

2005-10-31T23:59:59.000Z

226

Heat pump having improved defrost system  

DOE Patents (OSTI)

A heat pump system includes, in an operable relationship for transferring heat between an exterior atmosphere and an interior atmosphere via a fluid refrigerant: a compressor; an interior heat exchanger; an exterior heat exchanger; an accumulator; and means for heating the accumulator in order to defrost the exterior heat exchanger. 2 figs.

Chen, F.C.; Mei, V.C.; Murphy, R.W.

1998-12-08T23:59:59.000Z

227

Indoor air environment and night cooling energy efficiency of a southern German passive public school building operated by the heat recovery air conditioning unit  

Science Journals Connector (OSTI)

Abstract The recently built school building has adopted a novel heat recovery air conditioning system. Heat recovery efficiency of the heat recovery facility and energy conservation ratio of the air conditioning unit were analytically modeled, taking the ventilation networks into account. Following that, school classroom displacement ventilation and its thermal stratification have been numerically investigated concerning the effects of the heat flow flux of passive cooling within the ceiling concrete in the classroom due to night ventilation in summer which could result in cooling energy storage. Numerical results indicate that the promotion of passive cooling can simultaneously decrease the volume averaged indoor temperatures and the non-uniformity of indoor thermal distributions. Subsequent energy performance analysis demonstrates that classroom energy demands for ventilation and cooling could be reduced with the promotion of heat recovery efficiency of the ventilation facility, and the energy conservation ratio of the air-cooling unit decreases with the increasing temperatures of exhaust air and the heat flux value for passive cooling within the classroom ceiling concrete. Fitting correlations of heat recovery ventilation and cooling energy conservation have been presented.

Yang Wang; Fu-Yun Zhao; Jens Kuckelkorn; Xiao-Hong Li; Han-Qing Wang

2014-01-01T23:59:59.000Z

228

Determining the maximal capacity of a combined-cycle plant operating with afterburning of fuel in the gas conduit upstream of the heat-recovery boiler  

Science Journals Connector (OSTI)

The effect gained from afterburning of fuel in the gas conduit upstream of the heat-recovery boiler used as part of a PGU-450T combined-cycle plant is considered. The results obtained from ... electric and therma...

V. M. Borovkov; N. M. Osmanova

2011-01-01T23:59:59.000Z

229

Analysis of the behavior of an experimental absorption heat transformer for water purification for different mass flux rates in the generator  

Science Journals Connector (OSTI)

In the present study, first and second laws of thermodynamics have been used to analyse the performance of an experimental absorption heat transformer for water purification. Irreversibilities, coefficients of performance (COP) and exergy coefficients of performance (ECOP) were determined as function of the mass flow of hot water supplied to the generator and as function of the overall thermal specific energy consumption (OSTEC) parameter defined in this paper. The results showed that the system irreversibilities increase meanwhile the coefficients of performance and the exergy coefficient of performance decrease with an increment of the mass flow of hot water supplied to the generator. Also it was shown that the system performance is better when the production of purified water increases due to the increment of the heat recycled to the generator and evaporator.

Armando Huicochea; Wilfrido Rivera; Hiram Martnez; Javier Siqueiros; Erasmo Cadenas

2013-01-01T23:59:59.000Z

230

Heat Transfer Enhancement in Thermoelectric Power Generation.  

E-Print Network (OSTI)

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

Hu, Shih-yung

2009-01-01T23:59:59.000Z

231

Complex Compound Chemical Heat Pumps  

E-Print Network (OSTI)

industrial heat pumps. The main emphasis was directed towards a conceptual temperature amplifier bench scale prototype design, which allows for the conversion to heat amplifier operation by the mere exchange of adsorbent working fluid component without...

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

232

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

233

Tips: Heat Pumps | Department of Energy  

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

Heat Pumps Heat Pumps Tips: Heat Pumps June 24, 2013 - 5:48pm Addthis Heat pumps can be a cost-effective choice in moderate climates, especially if you heat your home with electricity. Heat pumps can be a cost-effective choice in moderate climates, especially if you heat your home with electricity. Heat pumps are the most efficient form of electric heating in moderate climates. Because they move heat rather than generate heat, heat pumps can provide equivalent space conditioning at as little as one quarter of the cost of operating conventional heating or cooling appliances. A heat pump does double duty as a central air conditioner by collecting the heat inside your house and pumping it outside. There are three types of heat pumps: air-to-air, water source, and geothermal. They collect heat from the air, water, or ground outside your

234

Heat Transfer Enhancement for Finned-tube Heat Exchangers with Winglets  

SciTech Connect

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

235

FEMP--Geothermal Heat Pumps  

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

heat pump-like an air conditioner or refrigera- heat pump-like an air conditioner or refrigera- tor-moves heat from one place to another. In the summer, a geothermal heat pump (GHP) operating in a cooling mode lowers indoor temperatures by transferring heat from inside a building to the ground outside or below it. Unlike an air condition- er, though, a heat pump's process can be reversed. In the winter, a GHP extracts heat from the ground and transfers it inside. Also, the GHP can use waste heat from summer air-conditioning to provide virtually free hot-water heating. The energy value of the heat moved is typically more than three times the electricity used in the transfer process. GHPs are efficient and require no backup heat because the earth stays at a relatively moderate temperature throughout the year.

236

Heat Requirements of Buildings  

Science Journals Connector (OSTI)

... and Ventilating Engineers in a publication entitled Recommendations for the Computation of Heat Requirements for Buildings (Pp. iii+41. Is. 9d.) This comprises a section of the ... parts. That on temperature-rise and rates of change gives the recommended values applicable to buildings ranging alphabetically from aircraft sheds to warehouses. The design of heating and ventilating installations ...

1942-02-28T23:59:59.000Z

237

Influence of steam injection and hot gas bypass on the performance and operation of a combined heat and power system using a recuperative cycle gas turbine  

Science Journals Connector (OSTI)

The influence of steam injection and hot gas bypass on the performance and operation of ... power (CHP) system using a recuperative cycle gas turbine was investigated. A full off-design analysis ... in steam gene...

Soo Young Kang; Jeong Ho Kim; Tong Seop Kim

2013-08-01T23:59:59.000Z

238

Waste Heat Reduction and Recovery for Improving Furnace Efficiency, Productivity and Emissions Performance: A BestPractices Process Heating Technical Brief  

SciTech Connect

This technical brief is a guide to help plant operators reduce waste heat losses associated with process heating equipment.

Not Available

2004-11-01T23:59:59.000Z

240

Method of measuring heat influx of a cryogenic transfer system. [Patent application  

DOE Patents (OSTI)

A method is provided for measuring the heat influx of a cryogenic transfer system. A gaseous phase of the cryogen used during normal operation of the system is passed through the system. The gaseous cryogen at the inlet to the system is tempered to duplicate the normal operating temperature of the system inlet. The temperature and mass flow rate of the gaseous cryogen is measured at the outlet of the system, and the heat capacity of the cryogen is determined. The heat influx of the system is then determined from known thermodynamic relationships.

Niemann, R.C.; Zelipsky, S.A.; Rezmer, R.R.; Smelser, P.

1980-10-29T23:59:59.000Z

Note: This page contains sample records for the topic "operating heat rate" 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

Fuzzy predictive control of district heating network  

Science Journals Connector (OSTI)

This paper presents a concept for controlling the supply temperature in district heating networks (DHNs) using model predictive control. Due to the inherent non-linearity in the response characteristics caused by varying flow rates the use of fuzzy dynamic matrix control (DMC) is proposed. The fuzzy partitions of the local finite impulse response (FIR) models are constructed by an axis-orthogonal, incremental partitioning scheme. Furthermore, a novel approach for determining future fuzzy trajectory based on heat load forecasts is implemented. It is demonstrated that the fuzzy DMC performs well for the case study considered. In addition, different set point strategies are applied and the results are evaluated with respect to operational costs. In this context it is shown that the trade-off between pumping and heat loss cost plays an important role in minimising overall costs.

S. Grosswindhager; M. Kozek; Andreas Voigt; Lukas Haffner

2013-01-01T23:59:59.000Z

242

Thermal single-well injection-withdrawal tracer tests for determining fracture-matrix heat transfer area  

E-Print Network (OSTI)

rates of rocks- to-fluid heat transfer, and thereby thesurface for heat transfer to injected fluids circulating influids, and thereby increase the overall rate of heat transfer

Pruess, K.

2011-01-01T23:59:59.000Z

243

Passive heat transfer means for nuclear reactors  

DOE Patents (OSTI)

An improved passive cooling arrangement is disclosed for maintaining adjacent or related components of a nuclear reactor within specified temperature differences. Specifically, heat pipes are operatively interposed between the components, with the vaporizing section of the heat pipe proximate the hot component operable to cool it and the primary condensing section of the heat pipe proximate the other and cooler component operable to heat it. Each heat pipe further has a secondary condensing section that is located outwardly beyond the reactor confinement and in a secondary heat sink, such as air ambient the containment, that is cooler than the other reactor component. Means such as shrouding normally isolated the secondary condensing section from effective heat transfer with the heat sink, but a sensor responds to overheat conditions of the reactor to open the shrouding, which thereby increases the cooling capacity of the heat pipe. By having many such heat pipes, an emergency passive cooling system is defined that is operative without electrical power.

Burelbach, James P. (Glen Ellyn, IL)

1984-01-01T23:59:59.000Z

244

The World's First InP 8x8 Monolithic Tunable Optical Router (MOTOR) Operating at 40 Gbps Line Rate per Port  

E-Print Network (OSTI)

on the world's first 8-channel monolithic tunable optical router (MOTOR) operating at 40 Gbps per port. The InP/InGaAsP approach. This platform allowed us to reduce absorption losses in the AWGR and delay line regions

Coldren, Larry A.

245

Definition: Heat | Open Energy Information  

Open Energy Info (EERE)

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

246

Spring 2014 Heat Transfer -1  

E-Print Network (OSTI)

Spring 2014 1 Heat Transfer - 1 Consider a cylindrical nuclear fuel rod of length L and diameter df and the tube at a rate m , and the outer surface of the tube is well insulated. Heat generation occurs within. The specific heat of water pc , and the thermal conductivity of the fuel rod fk are constants. The system

Virginia Tech

247

Refrigerant charge management in a heat pump water heater  

DOE Patents (OSTI)

Heat pumps that heat or cool a space and that also heat water, refrigerant management systems for such heat pumps, methods of managing refrigerant charge, and methods for heating and cooling a space and heating water. Various embodiments deliver refrigerant gas to a heat exchanger that is not needed for transferring heat, drive liquid refrigerant out of that heat exchanger, isolate that heat exchanger against additional refrigerant flowing into it, and operate the heat pump while the heat exchanger is isolated. The heat exchanger can be isolated by closing an electronic expansion valve, actuating a refrigerant management valve, or both. Refrigerant charge can be controlled or adjusted by controlling how much liquid refrigerant is driven from the heat exchanger, by letting refrigerant back into the heat exchanger, or both. Heat pumps can be operated in different modes of operation, and segments of refrigerant conduit can be interconnected with various components.

Chen, Jie; Hampton, Justin W.

2014-06-24T23:59:59.000Z

248

Simulation and analysis of district-heating and -cooling systems  

SciTech Connect

A computer simulation model, GEOCITY, was developed to study the design and economics of district heating and cooling systems. GEOCITY calculates the cost of district heating based on climate, population, energy source, and financing conditions. The principal input variables are minimum temperature, heating degree-days, population size and density, energy supply temperature and distance from load center, and the interest rate. For district cooling, maximum temperature and cooling degree-hours are required. From this input data the model designs the fluid transport and district heating systems. From this design, GEOCITY calculates the capital and operating costs for the entire system. GEOCITY was originally developed to simulate geothermal district heating systems and thus, in addition to the fluid transport and distribution models, it includes a reservoir model to simulate the production of geothermal energy from geothermal reservoirs. The reservoir model can be adapted to simulate the supply of hot water from any other energy source. GEOCITY has been used extensively and has been validated against other design and cost studies. GEOCITY designs the fluid transport and distribution facilities and then calculates the capital and operating costs for the entire system. GEOCITY can simulate nearly any financial and tax structure through varying the rates of return on equity and debt, the debt-equity ratios, and tax rates. Both private and municipal utility systems can be simulated.

Bloomster, C.H.; Fassbender, L.L.

1983-03-01T23:59:59.000Z

249

Geothermal Heat Pumps- Heating Mode  

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

In winter, fluid passing through this vertical, closed loop system is warmed by the heat of the earth; this heat is then transferred to the building.

250

Simulation study of a heat pump for simultaneous heating and cooling coupled to buildings  

E-Print Network (OSTI)

Simulation study of a heat pump for simultaneous heating and cooling coupled to buildings Redouane) 141-149" DOI : 10.1016/j.enbuild.2013.12.047 #12;ABSTRACT In several situations, a heat pump occur. Unlike a reversible heat pump that works alternatively in heating or cooling, a HPS operates

Paris-Sud XI, Université de

251

E-Print Network 3.0 - absorption-sorption heat pumps Sample Search...  

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

Corporation Auxiliary - Heat pump water heater 50... -gal tank, electric auxiliary heating Multiple operating modes: heat pump, hybrid and standard... and Ventilation Systems...

252

E-Print Network 3.0 - absorption-type heat pumps Sample Search...  

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

Corporation Auxiliary - Heat pump water heater 50... -gal tank, electric auxiliary heating Multiple operating modes: heat pump, hybrid and standard... and Ventilation Systems...

253

detonation rate  

Science Journals Connector (OSTI)

detonation rate, detonation velocity, velocity of detonation, V.O.D., detonating velocity, rate of detonation, detonating rate ? Detonationsgeschwindigkeit f

2014-08-01T23:59:59.000Z

254

Rational analysis of mass, momentum, and heat transfer phenomena in liquid storage tanks under realistic operating conditions: 2. Application to a feasibility study  

Science Journals Connector (OSTI)

This is the second part of a two-part paper that deals with modelling the thermal performances of storage tanks of liquid water coupled with solar-assisted heatpump systems. The computer code THESTA, described in detail in the first part, has been applied to compare configurations which differ from one another in the distribution and thickness of the insulating panels. These numerical experiments show very clearly the capability of the code in simulating realistic operating conditions. The validity of the present release is also discussed. The results obtained have been assumed to be a reliable theoretical support to the definition of the features of the storage device of a pilot plant.

F. Parrini; S. Vitale; L. Castellano

1992-01-01T23:59:59.000Z

255

Cr2O3 scale growth rates on metallic interconnectors derived from 40,000h solid oxide fuel cell stack operation  

Science Journals Connector (OSTI)

Abstract The ohmic resistance caused by Cr2O3 scale formation on metallic interconnects (MICs) can significantly contribute to the overall degradation of SOFC stacks. For this reason oxide scale growth on Cr5Fe1Y2O3 (CFY) and Fe22Cr0.5Mn (Crofer) was investigated by scanning electron microscopy (SEM) from post-test samples that were either exposed to air at 850 C (furnace) or operated in Hexis planar SOFC-stacks under dual atmospheres (anode and cathode conditions) at temperatures around 900 C. The study includes unique test results from a stack operated for 40,000 h. To analyze inhomogeneity in scale thicknesses a dedicated statistical image analysis method has been applied. SEM images were used to compare the structural phenomena related to MIC oxidation at different sample locations. The observed differences between different sample locations may relate to locally different conditions (temperature, pO2, H2O/O2-ratio). Cr2O3 scale growth on the anode side is found to be approximately twice as fast in comparison to the scale growth on cathode side. Finally, based on our time lapse analyses with extensive sampling it can be concluded that reliable predictions of scale growth requires statistical analyses over a period that covers at least a quarter (10,000 h) of the required SOFC stack lifetime (40,000 h).

Markus Linder; Thomas Hocker; Lorenz Holzer; K. Andreas Friedrich; Boris Iwanschitz; Andreas Mai; J. Andreas Schuler

2013-01-01T23:59:59.000Z

256

An improved absorption generator for solar-thermal powered heat pumps. Part 1: Feasibility  

SciTech Connect

Solar heated absorption chiller installations have been, typically, very expensive for their rating. The need to keep the liquid flowing within the collectors as cool as possible to enhance collector thermal efficiency, conflicts with the need to operate the absorption chiller at a higher temperature. The compromise usually results in poor collector efficiency as well as a relatively poor specific chiller effect. The proposed vortex generator permits a heat pump to operate efficiently with relatively low temperature solar heated fluid (70--80 C). As a result, the collectors are cooler and much more efficient. In addition, the specific heat pumping capacity is about 27% greater than conventional systems operating at the same reduced generator temperatures and, therefore, a smaller chiller is required. The economic consequences of these benefits will be presented in Part 2.

Fineblum, S. [Megadyne Inc., Rochester, NY (United States)

1997-12-31T23:59:59.000Z

257

An improved absorption generator for solar-thermal powered heat pumps. Part 2: Energy and economics  

SciTech Connect

Solar heated absorption chiller installations have been very expensive for their rating. To enhance collector thermal efficiency the liquid flowing within the collectors must be kept as cool as possible. However, there is also a need to operate the absorption reported earlier. The compromise usually results in poor collector efficiency as well as a relatively poor specific chiller effect. The proposed vortex generator permits a heat pump to operate efficiently with relatively low temperature solar heated fluid (70--80 C). As a result, the collectors are cooler and more efficient. As noted in Part 1, the specific heat pumping capacity is about 27% greater than conventional systems operating at the same reduced generator temperatures. Therefore, a smaller, less expensive chiller is required. The reduced investment in solar arrays and absorption chillers is estimated along with a range of paybacks.

Fineblum, S. [Megadyne Inc., Rochester, NY (United States)

1997-12-31T23:59:59.000Z

258

Guide to Combined Heat and Power Systems for Boiler Owners and...  

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

Combined Heat and Power Systems for Boiler Owners and Operators Guide to Combined Heat and Power Systems for Boiler Owners and Operators This guide presents useful information for...

259

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

E-Print Network (OSTI)

, The exergy destruction in each component and the exergy efficiency of the compressor, the second-law efficiency, and the exergy destruction are to be determined. Assumptions 1 Steady operating conditions exist is 2.006=== Btu/lbm63.28 Btu/lbm43.57 COP inw qL (b) The exergy destruction in each component

Kostic, Milivoje M.

260

Environmental Impact Statement (EIS) for the Transfer of the Heat Source / Radioisotope Themoelectric Generator Assembly and Test Operations From the Mound Site  

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

031 031 Federal Register / Vol. 63, No. 191 / Friday, October 2, 1998 / Notices SUPPLEMENTARY INFORMATION: The package listing contains the following information: (1) Title of the information collection package; (2) current OMB control number; (3) type of respondents; (4) estimated number of responses annually; (5) estimated total burden hours, annually, including recordkeeping hours required to provide the information; (6) purpose; and (7) number of collections. Package Title: Legal. Current OMB No.: 1910-0800. Type of Respondents: DOE management and operating contractors, and offsite contractors. Estimated Number of Responses: 2,719. Estimated Total Burden Hours: 21,052. Purpose: This information is required by the Department to ensure that legal resources and requirements are

Note: This page contains sample records for the topic "operating heat rate" 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

Heat balance for two commercial broiler barns with solar preheated ventilation air  

Science Journals Connector (OSTI)

In temperate climatic zones, solar air heaters can reduce heating loads, and increase winter ventilation rates thereby improving inside air quality and livestock performance without additional fuel input. A heat balance was carried out to measure bird heat production under field conditions on two commercial broiler barns to evaluate the impact of solar heated ventilation air on bird performance, and identify strategies to reduce winter heating load. Located 40km east of Montreal, Canada, the experimental broiler barns were identically built with three floors housing 6500 birds per floor in an all-in all-out fashion. Equipped with solar air pre-heaters over their fresh air inlets, the barns were instrumented to monitor inlet, inside and outside air conditions, ventilation rate and heating system operating time. The effects on bird performance were observed from November 2007 to March 2009 by alternating their operation between the barns. The measured sensible and total heat productions of 4.5W and 8.4W, respectively, for 1kg birds corresponded to laboratory measured values. Bird performance was not affected by the solar air pre-heaters which increased the ventilation rate above normal during only 20% of the daytime period. Room air temperature stratification resulted in 2040kW of heat losses during the winter, representing 25% of the total natural gas heat load. Because inside air moved directly to the fans, large and rapid increases in ventilation inlet air temperature, produced by the solar air pre-heaters, resulted in further heat losses equivalent to 15% of the solar energy recovered. Sustainable energy management in livestock barns requiring heating should incorporate an air mixing system to eliminate air temperature stratification and improve fan flows.

Sbastien Cordeau; Suzelle Barrington

2010-01-01T23:59:59.000Z

262

The Broadband Heating Rate Profile (BBHRP) VAP  

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

brown-97.pdf Clothiaux, E. E., T. P. Ackerman, G. G. Mace, K. P. Moran, R. T. Marchand, M. Miller, and B. E. Martner, 2000: Objective determination of cloud heights and...

263

Emissions characteristics of modern oil heating equipment  

SciTech Connect

Over the last 10 years there have been some very interesting developments in oil heating. These include higher static pressure burners, air atomizing nozzles, low firing rate nozzles, low heat loss combustion chambers and condensing boilers and furnaces. The current data base on the emissions characteristics of oil-fired residential heating equipment is based primarily on data taken in the 1970's. The objective of the work described in this report is to evaluate the effects of recent developments in oil-fired equipment on emissions. Detailed emissions measurements have been made on a number of currently available residential oil burners and whole systems selected to represent recent development trends. Some additional data was taken with equipment which is in the prototype stage. These units are a prevaporizing burner and a retention head burner modified with an air atomizing nozzle. Measurements include No{sub x}, smoke numbers, CO, gas phase hydrocarbon emissions and particulate mass emission rates. Emissions of smoke, CO and hydrocarbons were found to be significantly greater under cyclic operation for all burners tested. Generally, particulate emission rates were found to be 3 to 4 times greater in cyclic operation than in steady state. Air atomized burners were found to be capable of operation at much lower excess air levels than pressure atomized burners without producing significant amounts of smoke. As burner performance is improved, either through air atomization or prevaporization of the fuel, there appears to be a general trend towards producing CO at lower smoke levels as excess air is decreased. The criteria of adjusting burners for trace smoke may need to be abandoned for advanced burners and replaced with an adjustment for specific excess air levels. 17 refs., 15 figs., 6 tabs.

Krajewski, R.; Celebi, Y.; Coughlan, R.; Butcher, T.; McDonald, R.J.

1990-07-01T23:59:59.000Z

264

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

265

IEA Heat Pump Workshop November 8, 2011  

E-Print Network (OSTI)

Responsible load growth a goal Residential rates low-- $0.01/kWh Sales of air source Heat Pumps a goal #12IEA Heat Pump Workshop November 8, 2011 Atlanta, Georgia #12;Heat Pump Reliability And Installer.3 Million customers 1.1 million residential customers #12;How did Alabama Power Company get into Heat Pump

Oak Ridge National Laboratory

266

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

Energy Savers (EERE)

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

267

Heat transfer via dropwise condensation on hydrophobic microstructured surfaces .  

E-Print Network (OSTI)

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

Ruleman, Karlen E. (Karlen Elizabeth)

2009-01-01T23:59:59.000Z

268

BOREAS Operations  

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

Study Area Operations/Thompson Airport (NSA-Ops) Study Area Operations/Thompson Airport (NSA-Ops) NSA Operations (NSA-Ops) The Keewatin Air Hanger: site of BOREAS Ops 1994 Dr. Piers Sellers working in Ops, 1994 BOREAS "Air Force" The NASA C-130 The University of Wyoming King Air The NASA Helicopter The NRC Twin Otter The NCAR Electra The Ontario Chieftain Back to the BOREAS Photo Page Index Other Sites: NSA Photos ||NSA-BP Photos | NSA-Fen Photos | NSA-OA Photos | NSA-OBS Photos | NSA-OJP Photos | NSA-UBS Photos | NSA-YJP Photos | NSA-Ops Photos SSA Photos || SSA-Airport Photos | SSA-Fen Photos | SSA-Mix Photos | SSA-OA Photos | SSA-OBS Photos | SSA-OJP Photos | SSA-YA Photos | SSA-YJP Photos | SSA-Ops Photos | ORNL DAAC Home || ORNL Home || NASA || Privacy, Security, Notices || Data Citation || Rate Us || Help |

269

SSA Operations  

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

Area Operations (SSA-Ops) Area Operations (SSA-Ops) "BOREAS Ops" was located at the Snodrifters Lodge, in Candle Lake, Saskatchewan. Radiosonde balloon launch at Ops The NASA Helicopter lands at Ops A meeting at the Snodrifter's Lodge Release of a radiosonde at the SSA operations center in Candle Lake. Back to the BOREAS Photo Page Index Other Sites: NSA Photos ||NSA-BP Photos | NSA-Fen Photos | NSA-OA Photos | NSA-OBS Photos | NSA-OJP Photos | NSA-UBS Photos | NSA-YJP Photos | NSA-Ops Photos SSA Photos || SSA-Airport Photos | SSA-Fen Photos | SSA-Mix Photos | SSA-OA Photos | SSA-OBS Photos | SSA-OJP Photos | SSA-YA Photos | SSA-YJP Photos | SSA-Ops Photos | ORNL DAAC Home || ORNL Home || NASA || Privacy, Security, Notices || Data Citation || Rate Us || Help | User Services - Tel: +1 (865) 241-3952 or E-mail: uso@daac.ornl.gov

270

Critical reaction rates in hypersonic combustion chemistry  

SciTech Connect

High Mach number flight requires that the scramjet propulsion system operate at a relatively low static inlet pressure and a high inlet temperature. These two constraints can lead to extremely high temperatures in the combustor, yielding high densities of radical species and correspondingly poor chemical combustion efficiency. As the temperature drops in the nozzle expansion, recombination of these excess radicals can produce more product species, higher heat yield, and potentially more thrust. The extent to which the chemical efficiency can be enhanced in the nozzle expansion depends directly on the rate of the radical recombination reactions. A comprehensive assessment of the important chemical processes and an experimental validation of the critical rate parameters is therefore required if accurate predictions of scramjet performance are to be obtained. This report covers the identification of critical reactions, and the critical reaction rates in hypersonic combustion chemistry. 4 refs., 2 figs.

Oldenborg, R.C.; Harradine, D.M.; Loge, G.W.; Lyman, J.L.; Schott, G.L.; Winn, K.R.

1989-01-01T23:59:59.000Z

271

Bioelectrochemical Integration of Waste Heat Recovery, Waste...  

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

electrolytic cell, designed to integrate waste heat recovery (i.e a microbial heat recovery cell or MHRC), can operate as a fuel cell and convert effluent streams into...

272

Microchannel Heat Exchangers with Carbon Dioxide  

SciTech Connect

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

273

STUDY OF FROST GROWTH ON HEAT EXCHANGERS USED AS OUTDOOR COILS IN AIR SOURCE HEAT PUMP SYSTEMS  

E-Print Network (OSTI)

STUDY OF FROST GROWTH ON HEAT EXCHANGERS USED AS OUTDOOR COILS IN AIR SOURCE HEAT PUMP SYSTEMS OF FROST GROWTH ON HEAT EXCHANGERS USED AS OUTDOOR COILS IN AIR SOURCE HEAT PUMP SYSTEMS Dissertation . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 3.5.3 Air Side Heat Transfer Rates . . . . . . . . . . . . . . . . . . 43 3.5.4 Fluid Side Heat

274

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

275

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...

276

Solar Heating and Cooling  

Science Journals Connector (OSTI)

...radiation during good weather are not very high, and...Atmospheric Administration weather ser-vice measures total...largely to experi-mental operation of 3-ton LiBr-H2O...a million solar water heaters are in use in these countries...air House heating load Cold air return 'S T~rgeo...

John A. Duffie; William A. Beckman

1976-01-16T23:59:59.000Z

277

Industrial Heat Pump Design Options  

E-Print Network (OSTI)

There are numerous industries that can incorporate heat pumps into their operations to save energy costs and payoff the investment in well under two years. Many of these industries can cut energy costs associated with evaporation by over 75...

Gilbert, J. S.

278

Heat strain and heat stress for workers wearing protective suits at a hazardous waste site  

SciTech Connect

In order to evaluate the effects of heat stress when full body protective suits are worn, heart rates, oral temperatures and environmental parameters were measured for five unacclimatized male workers (25-33 years of age) who performed sampling activities during hazardous waste clean-up operations. The protective ensembles included laminated PVC-Tyvec chemical resistant hood suits with rubber boots, gloves, full facepiece dual cartridge respirators and hard hats. For comparison, measurements also were performed when the men worked at a similar level of activity while they wore ordinary work clothes. A comparison of the heart rates for the men working with and without suits indicated that wearing the suits imposed a heat stress equivalent to adding 6/sup 0/ to 11/sup 0/C (11/sup 0/ to 20/sup 0/F) to the ambient WBGT index. A similar result was obtained by calculating the WBGT in the microclimate inside the suits and comparing it to the ambient WBGT. These results indicate the following: 1) there exists a significant risk of heat injury during hazardous waste work when full body protective clothing is worn, and 2) threshold limit values for heat stress established by the ACGIH must be lowered substantially before extending them to cover workers under these conditions.

Paull, J.M.; Rosenthal, F.S.

1987-05-01T23:59:59.000Z

279

Application Study of a Single House Horizontal Heating System  

E-Print Network (OSTI)

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

Hang, Y.; Ying, D.

2006-01-01T23:59:59.000Z

280

Connecting the second exhaust-heat boiler to the operating first one under the conditions of flow circuits of combined-cycle plants with two gas-turbine units and one steam turbine  

Science Journals Connector (OSTI)

Problems arising with connecting the second exhaust-heat boiler to the first exhaust-heat boiler under load in the case of flow circuits of combined-cycle plants of type PGU-450 are considered. Similar problem...

Yu. A. Radin; I. A. Grishin; T. S. Kontorovich

2006-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "operating heat rate" 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

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

282

Experimental study of a photovoltaic solar-assisted heat-pump/heat-pipe system  

Science Journals Connector (OSTI)

A practical design for a heat pump with heat-pipe photovoltaic/thermal (PV/T) collectors is presented. The hybrid system is called the photovoltaic solar-assisted heat-pump/heat-pipe (PV-SAHP/HP) system. To focus on both actual demand and energy savings, the PV-SAHP/HP system was designed to be capable of operating in three different modes, namely, the heat-pipe, solar-assisted heat pump, and air-source heat-pump modes. Based on solar radiation, the system operates in an optimal mode. A series of experiments were conducted in Hong Kong to study the performance of the system when operating in the heat-pipe and the solar-assisted heat-pump modes. Moreover, energy and exergy analyses were used to investigate the total PV/T performance of the system.

H.D. Fu; G. Pei; J. Ji; H. Long; T. Zhang; T.T. Chow

2012-01-01T23:59:59.000Z

283

Heat Stroke  

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

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

284

Thermosolutal convection from a discrete heat and solute source in a vertical porous annulus  

E-Print Network (OSTI)

on the fluid flow and heat and mass transfer rates. The porous annulus is subject to heat and mass fluxes from, buoyancy ratio and radius ratio are investigated on the flow patterns, and heat and mass transfer rates and the rates of heat and mass transfer strongly depend on the location of the heat and solute source. Further

Lopez, John M.

285

Rate Schedules  

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

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

286

Marketing the Klamath Falls Geothermal District Heating system  

SciTech Connect

The Klamath Falls Geothermal District Heating system was completed in 1981 and, until 1992, there was no formal marketing plan for the system. This lack of marketing and the system history of poor availability combined to reduce or eliminate interest in connecting on the part of local building owners and it served only the original 14 government buildings connected at start up. The revenue from these buildings, however, did not cover the entire cost of operating the system. As a result, the city was faced with a difficult decision - develop the revenue required to make the system self-supporting or shut it down. As a result, a marketing strategy for the system was developed. A flat rate was developed in which the rate is negotiable, but for most customers approximates 50% of the gas bill. In addition, the flat rate reduced customer retrofit costs because it is not necessary to buy a meter. Finally, the flat rate is a guaranteed value for the first 10 years of the contract. To reduce retrofit costs, the new marketing plan eliminates the requirement for a customer heat exchanger. New customers are now connected directly into the distribution system with district loop water used as the building heating medium. The state operates two programs which have been used in the marketing plan. The first of these is available only to taxable entities and is referred to as the Business Energy Tax Credit (BETC). This program offers business a 35% tax credit on the costs associated with connection to the geothermal district heat system (retrofit, design, permits, etc.). The second state program is the Small Energy Loan Program (SELP). This program will loan the entire cost of the energy project to the customer. The new marketing strategy for the Klamath Falls system has concentrated on offering the customer an attractive and easy to understand rate structure, reduced retrofit cost and complexity for this building along with an attractive package of financing and tax credits. 1 tab.

Rafferty, K. (Geo-Heat Center, Klamath Falls, OR (United States))

1993-08-01T23:59:59.000Z

287

ENERGY ABSORBER HEAT PUMP SYSTEM TO SUPPLEMENT HEAT RECOVERY SYSTEMS IN AN INDOOR SWIMMING POOL  

Science Journals Connector (OSTI)

ABSTRACT Compared with convontional indoor swimming pools with traditional plant engineering, the Schwalmtal indoor swimming pool has a final energy consumption of just 40%. This low consumption is achieved by improved insulation of the building's enveloping surface, through the operation of systems for the recovery of heat from drain water and waste air as well as by the operation of a heat pump system to gain ambient heat. The decentralised heat recovery systems met between 40 and 80% of the heat requirements in the supply areas where they were used. The electric heat pump system, which is operated in the bivalent mode in parallel to a heating boiler, could generate 75% of the heat provided by the central heating circuit to meet the residual heat requirements. The report illustrates the structure of the residual heat requirements of the central heating circuit. A description is given of the measured coefficients of performance of the brine/water heat pump connected by a brine circuit with two different energy absorber types - energy stack and energy roof. Finally, the ambient energy gained with the absorbers is broken down into the various kinds of heat gains from radiation, convection, condensation etc. KEYWORDS Energy absorber; energy stack; energy roof; heat pump; heat recovery systems; indoor swimming pool; energy engineering concept.

K. Leisen

1988-01-01T23:59:59.000Z

288

Application of release rate data to hazard load calculations  

Science Journals Connector (OSTI)

The author illustrates methods of applying heat, smoke and toxic gas release rate data to calculating fire hazard loading values.

Edwin E. Smith

1974-08-01T23:59:59.000Z

289

ADVANCED HEAT EXCHANGERS USING TUNABLE NANOSCALE-MOLECULAR ASSEMBLY  

SciTech Connect

Steam condensation heat transfer on smooth horizontal tubes and enhanced tubes (TURBO-CDI and TURBO-CSL) along with nanoscale hydrophobic coated tubes was studied experimentally. Hydrophobic coatings have been created through self-assembled mono layers (SAMs) on copper alloy (99.9% Cu, 0.1% P) surfaces to enhance steam condensation through dropwise condensation. In general, a SAM system with a long-chain, hydrophobic group is nano-resistant, meaning that such a system forms a protective hydrophobic layer with negligible heat transfer resistance but a much stronger bond. When compared to complete filmwise condensation, the SAM coating on a plain tube increased the condensation heat transfer rate by a factor of 3 for copper alloy surfaces, under vacuum pressure (33.86 kPa) and by a factor of about 8 times when operated at atmospheric pressure (101 kPa). Lifetime of maintaining dropwise condensation is greatly dependent on the processing conditions.

Kwang J. Kim; Thomas W. Bell; Srinivas Vemuri; Sailaja Govindaraju

2004-01-01T23:59:59.000Z

290

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

E-Print Network (OSTI)

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

Gaskill, Travis

2012-02-14T23:59:59.000Z

291

Operational Demonstration Program | Department of Energy  

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

Operational Demonstration Program Operational Demonstration Program Operational Demonstration Program < Back Eligibility Commercial Savings Category Heating & Cooling Commercial Heating & Cooling Heating Home Weatherization Commercial Weatherization Sealing Your Home Cooling Construction Design & Remodeling Windows, Doors, & Skylights Ventilation Heat Pumps Appliances & Electronics Commercial Lighting Lighting Manufacturing Buying & Making Electricity Bioenergy Alternative Fuel Vehicles Hydrogen & Fuel Cells Water Energy Sources Solar Water Heating Wind Maximum Rebate $500,000 Program Info Funding Source CEFIA Start Date 2005 State Connecticut Program Type Industry Recruitment/Support Rebate Amount $150,000 - $500,000 Provider Clean Energy Finance and Investment Authority This program is currently closed. Applications were due in February 2012.

292

Consumer Winter Heating Oil Costs  

Gasoline and Diesel Fuel Update (EIA)

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

293

Rates - WAPA-137 Rate Order  

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

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

294

THEORY AND SIIVIULATION OF CYCIDTRON HEATING IN A LINEAR OCIUPOLE  

E-Print Network (OSTI)

conductivity model is used to calculate the cyclotron heating rate (electron or ion) in an arbitrary non been used to calculate the cyclotron heating rate for plasmas in various magnetic field configurations. This paper presents a method of calculating cyclotron heating rates that is based on integration of the local

Sprott, Julien Clinton

295

Fact #659: January 24, 2011 Fuel Economy Ratings for Vehicles...  

Energy Savers (EERE)

9: January 24, 2011 Fuel Economy Ratings for Vehicles Operating on Electricity Fact 659: January 24, 2011 Fuel Economy Ratings for Vehicles Operating on Electricity The...

296

Geothermal district heating system feasibility analysis, Thermopolis, Wyoming  

SciTech Connect

The purpose of this study is to determine the technical and economic feasibility of constructing and operating a district heating system to serve the residential, commercial, and public sectors in Thermopolis. The project geothermal resource assessment, based on reviews of existing information and data, indicated that substantial hot water resources likely exist in the Rose Dome region 10 miles northeast of Thermopolis, and with quantities capable of supporting the proposed geothermal uses. Preliminary engineering designs were developed to serve the space heating and hot water heating demands for buildings in the Thermopolis-East Thermopolis town service area. The heating district design is based on indirect geothermal heat supply and includes production wells, transmission lines, heat exchanger units, and the closed loop distribution and collection system necessary to serve the individual customers. Three options are presented for disposal of the cooled waters-reinjection, river disposal, and agricultural reuse. The preliminary engineering effort indicates the proposed system is technically feasible. The design is sized to serve 1545 residences, 190 businesses, and 24 public buildings. The peak design meets a demand of 128.2 million Btu at production rates of 6400 gpm.

Goering, S.W.; Garing, K.L.; Coury, G.; Mickley, M.C.

1982-04-26T23:59:59.000Z

297

Operations Information  

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

Standards BPA Operations Information (OPI) Transmission Services operates and plans for regional and national system needs. Transmission Services coordinates system operation and...

298

Development of an integrated building load and ground source heat pump model to assess heat pump and ground loop design and performance in a commercial office building.  

E-Print Network (OSTI)

??Ground source heat pumps (GSHPs) offer an efficient method for cooling and heating buildings, reducing energy usage and operating cost. In hot, arid regions such (more)

Blair, Jacob Dale

2014-01-01T23:59:59.000Z

299

Multidisciplinary University Research Initiative: High Operating...  

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

University Research Initiative (MURI) to develop high-operating temperature heat-transfer fluids for concentrating solar power (CSP) applications. The following...

300

Water Heating | OpenEI  

Open Energy Info (EERE)

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

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


301

Heat Transfer at Small Grashof Numbers  

Science Journals Connector (OSTI)

...January 1957 research-article Heat Transfer at Small Grashof Numbers J. J...physical arguments suggest that the heat transfer from a body, immersed in a fluid...the problem is small. However, heat-transfer rates predicted in this fashion...

1957-01-01T23:59:59.000Z

302

Process Heating Assessment and Survey Tool  

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

The Process Heating Assessment and Survey Tool (PHAST) introduces methods to improve thermal efficiency of heating equipment. This tool helps industrial users survey process heating equipment that consumes fuel, steam, or electricity, and identifies the most energy-intensive equipment. The tool can be used to perform a heat balance that identifies major areas of energy use under various operating conditions and test "what-if" scenarios for various options to reduce energy use.

303

Exergoeconomic analysis of a district heating system for geothermal energy using specific exergy cost method  

Science Journals Connector (OSTI)

Abstract This study presents the exergoeconomic analysis and evaluation in order to provide cost based information and suggests possible locations/components in a GDHS (geothermal district heating system) for improving the cost effectiveness. The analysis is based on the SPECO (specific exergy costing) method, and used to calculate exergy-related parameters and display cost flows for all streams and components. As a real case study, the Afyon GDHS in Turkey is considered based on actual operational data. The obtained results show that the unit exergy cost of heat produced by the Afyon GDHS is calculated as average 5624$/h. The HEX (heat exchanger)-III among all components should be improved quickly due to the high total operating cost rate and relative cost difference. The HEX-I and PM (pump)-V have the highest exergoeconomic factors among all other system components due to the high owning and operating costs of these components. The heat production costs per exergy unit for all the \\{HEXs\\} decrease due to the high exergy destruction cost rate of the system, while the well head temperature and ambient temperature increase. The SPECO method may be used to improve the cost effectiveness according to exergy rates in \\{GDHSs\\} as a thermal system.

Mehmet Ali Alkan; Ali Keeba?; Nurettin Yamankaradeniz

2013-01-01T23:59:59.000Z

304

Intermittent experimental study of a vertical ground source heat pump system  

Science Journals Connector (OSTI)

Abstract In this paper, the intermittent experiment of a vertical ground source heat pump (GSHP) system is investigated and the corresponding geo-temperature variations are studied. The performance of the GSHP system under intermittent operation and the comparisons of different intermittent modes are presented in the paper. The parameters of soil backfill material, air temperature and inlet volume flow rate are also investigated. Experimental results suggest that, due to the recovery in ground thermal energy in intermittent time, the heat exchange rate and the operation performance coefficient (COP) of the heat pump increases, and the compressor power decreases in the successive working. But an insufficient soil recovery time leads to a rapid decline of the performance parameters and the soil temperature. The temperature transports faster under large soil thermal conductivity conditions and the soil temperature decreases more quickly and recovers more slowly with larger inlet flow rate and lower weather temperature for different soil thermal diffusivities. Through multiple nonlinear regression analysis, a curve formula can be fitted to predict the soil temperature variations under intermittent operation of the ground source heat pump in winter, Dalian. It can be found that the soil temperature increases at an exponential function with each factor.

Yan Shang; Ming Dong; Sufen Li

2014-01-01T23:59:59.000Z

305

AGN Heating through Cavities and Shocks  

E-Print Network (OSTI)

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

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

2006-11-04T23:59:59.000Z

306

The Hardy inequality and the heat equation with magnetic field in any dimension  

E-Print Network (OSTI)

In the Euclidean space of any dimension d, we consider the heat semigroup generated by the magnetic Schroedinger operator from which an inverse-square potential is subtracted in order to make the operator critical in the magnetic-free case. Assuming that the magnetic field is compactly supported, we show that the polynomial large-time behaviour of the heat semigroup is determined by the eigenvalue problem for a magnetic Schroedinger operator on the (d-1)-dimensional sphere whose vector potential reflects the behaviour of the magnetic field at the space infinity. From the spectral problem on the sphere, we deduce that in d=2 there is an improvement of the decay rate of the heat semigroup by a polynomial factor with power proportional to the distance of the total magnetic flux to the discrete set of flux quanta, while there is no extra polynomial decay rate in higher dimensions. To prove the results, we establish new magnetic Hardy-type inequalities for the Schroedinger operator and develop the method of self-similar variables and weighted Sobolev spaces for the associated heat equation.

Cristian Cazacu; David Krejcirik

2014-09-23T23:59:59.000Z

307

CH Packaging Operations Manual  

SciTech Connect

This procedure provides instructions for assembling the CH Packaging Drum payload assembly, Standard Waste Box (SWB) assembly, Abnormal Operations and ICV and OCV Preshipment Leakage Rate Tests on the packaging seals, using a nondestructive Helium (He) Leak Test.

Washington TRU Solutions LLC

2005-06-13T23:59:59.000Z

308

Transmission and Storage Operations  

Energy Savers (EERE)

to see minimal to none in static or dynamic mode) - Rates are dependent on size, mechanical wear and operating pressures * PM * PdM 5 Methane Release Reduction Can the gas be...

309

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

310

Enhancing the operation of a pulsed combustor with trajectory-correction control K.D. Edwards, K. Nguyen  

E-Print Network (OSTI)

inventory is rapidly consumed and slowly restocked resulting in a high degree of variability in combustion the trajectory of the system toward the more stable operating mode. Emission levels of unburned hydrocarbons convective heat and mass transfer rates and produce lower pollutant emission levels than steady- flow

Tennessee, University of

311

Central heat engine cost and availability study  

SciTech Connect

This report documents the performance and cost of commercially available heat engines for use at solar power plants. The scope of inquiry spans power ratings of 500 kW to 50 MW and peak cycle temperatures of 750 /sup 0/F to 1200 /sup 0/F. Data were collected by surveying manufacturers of steam turbines, organic Rankine (ORC) systems, and ancillary equipment (steam condensers, cooling towers, pumps, etc.). Methods were developed for estimating design-point and off-design efficiencies of steam Rankine cycle (SRC) and ORC systems. In the size-temperature range of interest, SRC systems were found to be the only heat engines requiring no additional development effort, and SRC capital and operating cost estimates were developed. Commercially available steam turbines limit peak cycle temperatures to about 1000 /sup 0/F in this size range, which in turn limits efficiency. Other systems were identified that could be prototyped using existing turbomachines. These systems include ORC, advanced SRC, and various configurations employing Brayton cycle equipment, i.e., gas turbines. The latter are limited to peak cycle temperatures of 1500 /sup 0/F in solar applications, based on existing heat-exchanger technology. The advanced systems were found to offer performance advantages over SRC in specific cases. 7 refs., 30 figs., 20 tabs.

Not Available

1987-11-01T23:59:59.000Z

312

Rate schedule  

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

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

313

Heat transfer and fluid flow characteristics of microchannels with internal longitudinal fins.  

E-Print Network (OSTI)

??Electronic components generate large amount of heat during their operation, which requires to be dissipated. Over the past decade, internal heat generation levels have exponentially (more)

Foong, Andrew Jun Li

2009-01-01T23:59:59.000Z

314

Residential Multi-Function Gas Heat Pump: Efficient Engine-Driven...  

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

operate a conventional electric heat pump system, fuel is first converted to energy at a power plant where the waste heat is typically discharged to the environment. Electrical...

315

Heat pipes for use in a magnetic field  

DOE Patents (OSTI)

A heat pipe configuration for use in a magnetic field environment of a fusion reactor is disclosed. Heat pipes for operation in a magnetic field when liquid metal working fluids are used are optimized by flattening of the heat pipes having an unobstructed annulus which significantly reduces the adverse side region effect of the prior known cylindrically configured heat pipes. The flattened heat pipes operating in a magnetic field can remove 2--3 times the heat as a cylindrical heat pipe of the same cross sectional area. 4 figs.

Werner, R.W.; Hoffman, M.A.

1983-07-19T23:59:59.000Z

316

Experimental Study on Energy Efficiency of Heat-source Tower Heat Pump Units in Winter Condition  

Science Journals Connector (OSTI)

Building energy consumption in China has been increasing rapidly. And a small increase in the operation efficiency of the air-conditioning system can substantially decrease it. In this paper a new type heat pump is developed to improve the performance ... Keywords: Heat-source tower, Heat pump, Seasonal energy efficiency ratio(SEER), Hermal properties

Li Nianping; Zhang Wenjie; Wang Lijie; Liu Qiuke; Hu Jinhua

2011-01-01T23:59:59.000Z

317

Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters  

SciTech Connect

This paper explores the laboratory performance of five integrated Heat Pump Water Heaters (HPWHs) across a wide range of operating conditions representative of US climate regions. HPWHs are expected to provide significant energy savings in certain climate zones when compared to typical electric resistance water heaters. Results show that this technology is a viable option in most climates, but differences in control schemes and design features impact the performance of the units tested. Tests were conducted to map heat pump performance across the operating range and to determine the logic used to control the heat pump and the backup electric heaters. Other tests performed include two unique draw profile tests, reduced air flow performance tests and the standard DOE rating tests. The results from all these tests are presented here for all five units tested. The results of these tests will be used to improve the EnergyPlus heat pump water heater for use in BEopt(tm) whole-house building simulations.

Sparn, B.; Hudon, K.; Christensen, D.

2014-06-01T23:59:59.000Z

318

heat pump | OpenEI  

Open Energy Info (EERE)

heat pump heat pump Dataset Summary Description View 2010 energy efficiency data from AeroSys Inc, Coaire, Cold Point, First Operations, LG Electronics, Nordyne, and Quietside manufacturers. Data includes cooling capacity, cooling performance, heating capacity, and heating performance. Spreadsheet was created by combining the tables in pdf files that are included in the zip file. Source Energy Applicance Data - United States Federal Trade Commission, www.ftc.gov Date Released Unknown Date Updated Unknown Keywords air conditioner central air conditioner efficiency efficient energy heat pump Data application/vnd.ms-excel icon 2010_CentralAC_All.xls (xls, 82.4 KiB) application/zip icon 2010CentralAirConditioner.zip (zip, 398.2 KiB) Quality Metrics Level of Review Some Review

319

Northeast Home Heating Oil Reserve  

Gasoline and Diesel Fuel Update (EIA)

Northeast Home Heating Oil Reserve Northeast Home Heating Oil Reserve Information on the Northeast Home Heating Oil Reserve is available from the U.S. Department of Energy (DOE) Office of Petroleum Reserves web site at http://www.fossil.energy.gov/programs/reserves/heatingoil/. Northeast Home Heating Oil Reserve (NEHHOR) inventories now classified as ultra-low sulfur distillate (15 parts per million) are not considered to be in the commercial sector and therefore are excluded from distillate fuel oil supply and disposition statistics in Energy Information Administration publications, such as the Weekly Petroleum Status Report, Petroleum Supply Monthly, and This Week In Petroleum. Northeast Home Heating Oil Reserve Terminal Operator Location (Thousand Barrels) Hess Corp. Groton, CT 500*

320

Enhanced heat transfer for thermionic power modules  

SciTech Connect

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

Johnson, D.C.

1981-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "operating heat rate" 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

Heat exchanger containing a component capable of discontinuous movement  

DOE Patents (OSTI)

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

Wilson, David Gordon (Winchester, MA)

2002-01-01T23:59:59.000Z

322

Heat exchanger containing a component capable of discontinuous movement  

DOE Patents (OSTI)

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

Wilson, D.G.

1993-11-09T23:59:59.000Z

323

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

324

Sonoma State Hospital, Eldridge, California, geothermal-heating system: conceptual design and economic feasibility report  

SciTech Connect

The Sonoma State Mental Hospital, located in Eldridge, California, is presently equipped with a central gas-fired steam system that meets the space heating, domestic hot water, and other heating needs of the hospital. This system is a major consumer of natural gas - estimated at 259,994,000 cubic feet per year under average conditions. At the 1981 unit gas rate of $0.4608 per therm, an average of $1,258,000 per year is required to operate the steam heating system. The hospital is located in an area with considerable geothermal resources as evidenced by a number of nearby hot springs resorts. A private developer is currently investigating the feasibility of utilizing geothermally heated steam to generate electricity for sale to the Pacific Gas and Electric Company. The developer has proposed to sell the byproduct condensed steam to the hospital, which would use the heat energy remaining in the condensate for its own heating needs and thereby reduce the fossil fuel energy demand of the existing steam heating system. The geothermal heating system developed is capable of displacing an estimated 70 percent of the existing natural gas consumption of the steam heating system. Construction of the geothermal fluid distribution and collection system and the retrofits required within the buildings are estimated to cost $1,777,000. Annual expenses (operation and maintenance, insurance, and geothermal fluid purchase) have been estimated to be $40,380 per year in 1981 dollars. The proposed geothermal heating system could then be completely paid for in 32 months by the savings in natural gas purchases that would result.

Not Available

1982-02-01T23:59:59.000Z

325

Natural Zeolites in Solar Energy Heating, Cooling, and Energy Storage  

Science Journals Connector (OSTI)

...thereby reducing the energy consumption by almost half. The concept...heat, or any type of fossil fuel. This heat pump has two operating...of the internal combustion engine as the heat source for the...utilizing the waste heat of the engine with a 60 sec cycling time...

Dimiter I. Tchernev

326

Definition: Ground Source Heat Pumps | Open Energy Information  

Open Energy Info (EERE)

Pumps Pumps Jump to: navigation, search Dictionary.png Ground Source Heat Pumps A Ground Source Heat Pump is a central building heating and/or cooling system that takes advantage of the relatively constant year-round ground temperature to pump heat to or from the ground.[1][2][3] View on Wikipedia Wikipedia Definition A geothermal heat pump or ground source heat pump (GSHP) is a central heating and/or cooling system that pumps heat to or from the ground. It uses the earth as a heat source (in the winter) or a heat sink (in the summer). This design takes advantage of the moderate temperatures in the ground to boost efficiency and reduce the operational costs of heating and cooling systems, and may be combined with solar heating to form a geosolar system with even greater efficiency. Ground source heat pumps

327

Discussions on Disposal Forms of Auxiliary Heat Source in Surface Water Heat Pump System  

E-Print Network (OSTI)

This paper presents two common forms of auxiliary heat source in surface water heat pump system and puts forward the idea that the disposal forms affect operation cost. It deduces operation cost per hour of the two forms. With a project...

Qian, J.; Sun, D.; Li, X.; Li, G.

2006-01-01T23:59:59.000Z

328

High Water Heating Bills on Lockdown at Idaho Jail | Department of Energy  

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

High Water Heating Bills on Lockdown at Idaho Jail High Water Heating Bills on Lockdown at Idaho Jail High Water Heating Bills on Lockdown at Idaho Jail August 19, 2010 - 12:05pm Addthis The Blaine County Public Safety Facility houses between 60 and 80 prisoners and roughly 30 staffers. | Photo courtesy of Blaine The Blaine County Public Safety Facility houses between 60 and 80 prisoners and roughly 30 staffers. | Photo courtesy of Blaine Lindsay Gsell What does this project do? The new solar thermal hot water system will provide nearly 70 percent of the BTUs required for heating 600,000 gallons of water for the jail annually, saving the county more than $4,000 a year in electricity costs at current rates. In Hailey, Idaho, one 330,000 square foot building - the Blaine County Public Safety Facility - accounts for the county's highest operational

329

Theoretical and experimental study of a heat pipe in zero-G for electrochemical cell cooling  

SciTech Connect

A new thermal concept to be used with Li/SOCL2 batteries is presented. A thermal model of a grooved nickel heat pipe under uniform heat input is developed, and an experimental assembly is made to simulate the operating conditions in zero-G. It is shown how this new thermal concept can provide the following for the electrochemical cell: thermal cooling by heat pipe, mechanical reinforcement, and current collection. The thermal behavior of a Li/SOCL2 cell under high rate discharge using this concept is compared with that of a traditional concept (aluminum corset around the cell which is fixed to a coldplate). A thermal model is established that uses ESACAP software including about 100 nodes to represent the cell and the aluminum pipe or the heat pipe. 10 refs.

Alain, A.; Ali, S.; Luc, F.J. (Ecole Nationale Superieure de Mecanique et d'Aerotechnique, Poitiers, (France) SAFT, Poitiers, (France))

1991-07-01T23:59:59.000Z

330

Micro gas turbine cogeneration system with latent heat storage at the University: Part III: Temperature control schedule  

Science Journals Connector (OSTI)

Abstract The latent heat storage system is a novel heat storage system. At the University under service conditions, it was demonstrated with a micro gas turbine (MGT) cogeneration system (CGS). Expanding the latent heat storage system into new applications is expected to save energy economically with high density energy storage and reduce exhaust emissions and reduce operational costs. This is the first demonstration of using a latent heat storage system with CGS under service condition and its characteristics are very important. In Part I, a fixed operating schedule of the system was planned and demonstrated at the University. The charge/discharge cycles of the latent heat storage system were repeated for 407 times. The energy flow test of the system shows the importance of the heat release source and total system design. In Part II, an irregular charge case of the latent heat storage system was discussed when the prime mover of the system was operated at a part load and thermal priority mode. A highly sophisticated system design that solves these problems was necessary for extending the applications of the latent heat storage system. In Part III, a temperature control schedule of the system was demonstrated during winter mornings using a new programmable logic controller (PLC). Using a fixed schedule, the MGT-CGS with latent heat storage reduced the CO2 emission when the energy utilization factor was above 50%. The temperature control schedule was considered to be better than the fixed schedule, both in terms of the operational efficiency of the overall system and CO2 reduction. The temperature control schedule was executed using an empirical formula for the temperature rise in a classroom. The restriction on the operation time by the contract with the gas supplier and the low heating capacity of the CGS affected the heating time and temperature rise. The temperature rise in the classroom was almost proportional to the integrated temperature difference across the hot water header of the heating system. On cold days, the rate of temperature rise produced by the CGS was very slow, therefore, additional heat supplied by the original boiler was used to increase the temperature rise. If larger latent heat storage systems will be developed in future, it will be expected that the temperature of the classrooms are kept more comfortable with less energy consumptions and lower CO2 emission.

Osamu Kurata; Norihiko Iki; Takayuki Matsunuma; Tetsuhiko Maeda; Satoshi Hirano; Katsuhiko Kadoguchi; Hiromi Takeuchi; Hiro Yoshida

2014-01-01T23:59:59.000Z

331

Initial Operation of the High Temperature Electrolysis Integrated Laboratory Scale Experiment at INL  

SciTech Connect

An integrated laboratory scale, 15 kW high-temperature electrolysis facility has been developed at the Idaho National Laboratory under the U.S. Department of Energy Nuclear Hydrogen Initiative. Initial operation of this facility resulted in over 400 hours of operation with an average hydrogen production rate of approximately 0.9 Nm3/hr. The integrated laboratory scale facility is designed to address larger-scale issues such as thermal management (feed-stock heating, high-temperature gas handling), multiple-stack hot-zone design, multiple-stack electrical configurations, and other integral issues. This paper documents the initial operation of the ILS, with experimental details about heat-up, initial stack performance, as well as long-term operation and stack degradation.

C. M. Stoots; J. E. O'Brien; K. G. Condie; J. S. Herring; J. J. Hartvigsen

2008-06-01T23:59:59.000Z

332

Heat pump system with selective space cooling  

DOE Patents (OSTI)

A reversible heat pump provides multiple heating and cooling modes and includes a compressor, an evaporator and heat exchanger all interconnected and charged with refrigerant fluid. The heat exchanger includes tanks connected in series to the water supply and a condenser feed line with heat transfer sections connected in counterflow relationship. The heat pump has an accumulator and suction line for the refrigerant fluid upstream of the compressor. Sub-cool transfer tubes associated with the accumulator/suction line reclaim a portion of the heat from the heat exchanger. A reversing valve switches between heating/cooling modes. A first bypass is operative to direct the refrigerant fluid around the sub-cool transfer tubes in the space cooling only mode and during which an expansion valve is utilized upstream of the evaporator/indoor coil. A second bypass is provided around the expansion valve. A programmable microprocessor activates the first bypass in the cooling only mode and deactivates the second bypass, and vice-versa in the multiple heating modes for said heat exchanger. In the heating modes, the evaporator may include an auxiliary outdoor coil for direct supplemental heat dissipation into ambient air. In the multiple heating modes, the condensed refrigerant fluid is regulated by a flow control valve. 4 figs.

Pendergrass, J.C.

1997-05-13T23:59:59.000Z

333

Heat pump system with selective space cooling  

DOE Patents (OSTI)

A reversible heat pump provides multiple heating and cooling modes and includes a compressor, an evaporator and heat exchanger all interconnected and charged with refrigerant fluid. The heat exchanger includes tanks connected in series to the water supply and a condenser feed line with heat transfer sections connected in counterflow relationship. The heat pump has an accumulator and suction line for the refrigerant fluid upstream of the compressor. Sub-cool transfer tubes associated with the accumulator/suction line reclaim a portion of the heat from the heat exchanger. A reversing valve switches between heating/cooling modes. A first bypass is operative to direct the refrigerant fluid around the sub-cool transfer tubes in the space cooling only mode and during which an expansion valve is utilized upstream of the evaporator/indoor coil. A second bypass is provided around the expansion valve. A programmable microprocessor activates the first bypass in the cooling only mode and deactivates the second bypass, and vice-versa in the multiple heating modes for said heat exchanger. In the heating modes, the evaporator may include an auxiliary outdoor coil for direct supplemental heat dissipation into ambient air. In the multiple heating modes, the condensed refrigerant fluid is regulated by a flow control valve.

Pendergrass, Joseph C. (Gainesville, GA)

1997-01-01T23:59:59.000Z

334

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

E-Print Network (OSTI)

Efficiency Ratings for the Daiken AC (Americas), Inc. Altherma Air-to-Water Source Heat Pump System Description Model No. Capacity (tons) Space Heating Space Cooling SEER Water Heating Efficiency (E.F.)1 CEC Listing Date Heating Combined Hydronic HSPF E.F. Split Altherma LT ERLQ036

335

Geothermal district heating systems  

SciTech Connect

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

Budney, G.S.; Childs, F.

1982-01-01T23:59:59.000Z

336

Proceedings of HT'03 2003 Summer Heat Transfer Conference  

E-Print Network (OSTI)

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

Walker, D. Greg

337

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

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

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

338

Designing, testing, and analyzing coupled, flux transformer heat  

E-Print Network (OSTI)

of identical effective length, this research shows that sufficient heat can be transferred across the system to work effectively in situations where the single heat pie will fail to operate. The thermal resistance in the condenser and evaporator sections need...

Renzi, Kimberly Irene

1998-01-01T23:59:59.000Z

339

Case study of underground pipe ground coupled heat pump system  

Science Journals Connector (OSTI)

Aiming to give some advices on the ground coupled heat pump system design in Sichuan Province, China, a typical ground source heat pump (GSHP) system in Sichuan Province was tested in a whole operational year,...

Min Zheng ??; Bai-yi Li ???; Zheng-yong Qiao ???

2012-03-01T23:59:59.000Z

340

Performance of a Heat Pump Water Heater in the Hot-Humid Climate, Windermere, Florida (Fact Sheet), Building America Case Study: Technology Solutions for New and Existing Homes, Building Technologies Office (BTO)  

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

Performance of a Performance of a Heat Pump Water Heater in the Hot-Humid Climate Windermere, Florida Over recent years, heat pump water heaters (HPWHs) have become more read- ily available and more widely adopted in the marketplace. A key feature of an HPWH unit is that it is a hybrid system. When conditions are favorable, the unit will operate in heat pump mode (using a vapor compression system that extracts heat from the surrounding air) to efficiently provide domestic hot water (DHW). Homeowners need not adjust their behavior to conform to the heat pump's capabilities. If a heat pump cannot meet a higher water draw demand, the heater will switch to electric resistance to provide a higher heating rate. This flexibility

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341

A new cascade-type heat conversion system  

SciTech Connect

Various heat conversion systems have different operating temperatures. This paper shows how, in a solar energy system some of the waste heat from a thermophotovoltaic arrangement can be made to operate a thermionic power generator. The waste heat of the thermionic power generator can then be made to operate an alkali-metal thermal electric converter, and the waste heat from the alkali-metal thermal electric converter as well as the rest of the waste heat of the thermophotovoltaic system can be made to operate a methane reformation system. Stored heat from the methane reformation system can be made to operate the system at night. The overall system efficiency of the example shown is 42.6%. As a prime source of heat a nuclear pile or burning hydrogen may be used.

Newman, E. [Twenty-First Century Power Co., Northridge, CA (United States)

1996-12-31T23:59:59.000Z

342

Multiple pollutant removal using the condensing heat exchanger: Phase 1 final report, November 1995--June 1997. Addendum 2: Task 3 topical report -- Long term wear test  

SciTech Connect

Long-term operation of a condensing heat exchanger under typical coal-fired flue gas conditions was investigated in Phase 1, Task 3 of the Multiple Pollutant Removal Using the Condensing Heat Exchanger test program. The specific goal of this task was to determine the amount of wear, if any, on the Teflon{reg_sign}-covered heat transfer tubes in a condensing heat exchanger. A pilot-scale single-stage condensing heat exchanger (CHX{reg_sign}) was operated under typical coal-fired flue gas conditions on a continuous basis for a period of approximately 10 months. Operating conditions and particulate loadings for the test unit were monitored, Teflon{reg_sign} film thickness measurements were conducted, and surface replications (which duplicate the surface finish at the microscopic level) were taken at various times during the test. Data from the test indicate that virtually no decrease in Teflon{reg_sign} thickness was observed for the coating on the first two rows of heat exchanger tubes, even at high inlet particulate loadings (400 mg/dscm [0.35 lb/10{sup 6} Btu]). Evidence of wear was present only at the microscopic level, and even then was very minor in severity. Operation at high inlet particulate loadings resulted in accumulated ash deposits within the heat exchanger. Installation of a modified (higher flow rate) wash nozzle manifold substantially reduced subsequent deposit formation.

Kudlac, G.A.

1998-06-01T23:59:59.000Z

343

Definition: System Operating Limit | Open Energy Information  

Open Energy Info (EERE)

Operating Limit Operating Limit Jump to: navigation, search Dictionary.png System Operating Limit The value (such as MW, MVar, Amperes, Frequency or Volts) that satisfies the most limiting of the prescribed operating criteria for a specified system configuration to ensure operation within acceptable reliability criteria. System Operating Limits are based upon certain operating criteria. These include, but are not limited to: Facility Ratings (Applicable pre- and post- Contingency equipment or facility ratings), Transient Stability Ratings (Applicable pre- and post-Contingency Stability Limits), Voltage Stability Ratings (Applicable pre- and post- Contingency Voltage Stability), System Voltage Limits (Applicable pre- and post- Contingency Voltage Limits)[1] Also Known As SOL

344

Heat transfer characteristics of laminar methane/air flame impinging normal to a cylindrical surface  

SciTech Connect

An experimental study has been conducted to determine the heat transfer characteristics of methane/air laminar flames impinging normal to a cylindrical surface. Effects of variations in the values of Reynolds number (Re = 600-1300), equivalence ratio ({phi} = 0.8-1.3), dimensionless separation distance (H/d = 1-5), and burner diameter to cylinder diameter ratio (d/D = 0.0538-0.1076) have been investigated. Three important configurations, viz., flame inner reaction zone far away, just touching and intercepted by the impingement surface, were examined in detail. High stagnation point heat fluxes were obtained when tip of the flame inner reaction zone just touched the target surface. Stagnation point heat fluxes were either zero or negative when the inner reaction zone was intercepted by the impingement surface. An off-stagnation peak in heat flux was obtained at moderate separation distances above the flame tip. Both stagnation point and peak heat fluxes increased with Re when the inner reaction zone length was less than the separation distance. Heat fluxes in the wall-jet region were high at high Re. Maximum heat fluxes were obtained for initially fuel-rich mixture conditions due to entrainment of the surrounding air. Smaller burner diameters produced high heat flux at the stagnation region for fixed Reynolds number and opposite trends were seen in the wall-jet region. A secondary rise in stagnation point heat flux was obtained at larger separation distances. This secondary rise in heat flux was quite significant for larger burner diameters and at low flow rates. Correlations were developed for stagnation point heat flux. Results were also compared with flat plate under identical operating conditions. (author)

Chander, Subhash; Ray, Anjan [Department of Mechanical Engineering, Indian Institute of Technology, Delhi, New Delhi 110 016 (India)

2007-11-15T23:59:59.000Z

345

Integrated solar heating unit  

SciTech Connect

This patent describes an integral solar heating unit with an integral solar collector and hot water storage system, the unit comprising: (a) a housing; (b) a flat plate solar collector panel mounted in the housing and having a generally horizontal upper edge and an uninsulated, open back surface; (c) a cylindrical hot water tank operatively connected to the solar collector panel and mounted in the housing generally parallel to and adjacent to the upper edge; (d) the housing comprising a hood around the tank a pair of side skirts extending down at the sides of the panel. The hood and side skirts terminate at lower edges which together substantially define a plane such that upon placing the heating unit on a generally planar surface, the housing substantially encapsulates the collector panel and hot water tank in a substantially enclosed air space; (e) the collector including longitudinally extended U-shaped collector tubes and a glazed window to pass radiation through to the collector tubes, and a first cold water manifold connected to the tubes for delivering fresh water thereto and a second hot water manifold connected to the tubes to remove heated water therefrom. The manifolds are adjacent and at least somewhat above and in direct thermal contact with the tank; and, (f) the skirts and hood lapping around the collector panel, exposing only the glazed window, such that everything else in the heating unit is enclosed by the housing such that heat emanating from the uninsulated, open back face of the collector and tank is captured and retained by the housing to warm the manifolds.

Larkin, W.J.

1987-01-20T23:59:59.000Z

346

Test results of a Stirling engine utilizing heat exchanger modules with an integral heat pipe  

SciTech Connect

The Heat Pipe Stirling Engine (HP-1000), a free-piston Stirling engine incorporating three heat exchanger modules, each having a sodium filled heat pipe, has been tested at the NASA-Lewis Research Center as part of the Civil Space Technology Initiative (CSTI). The heat exchanger modules were designed to reduce the number of potential flow leak paths in the heat exchanger assembly and incorporate a heat pipe as the link between the heat source and the engine. An existing RE-1000 free-piston Stirling engine was modified to operate using the heat exchanger modules. This paper describes heat exchanger module and engine performance during baseline testing. Condenser temperature profiles, brake power, and efficiency are presented and discussed.

Skupinski, R.C.; Tower, L.K.; Madi, F.J.; Brusk, K.D.

1993-04-01T23:59:59.000Z

347

New and Existing Buildings Heating and Cooling Opportunities: Dedicated Heat Recovery Chiller  

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

Langfitt Langfitt U S Department of State Overseas Buildings Operations Mechanical Engineering Division *Engineers are working Harder AND Smarter *New Energy Economy *Heating Is Where The Opportunity Is  39% of total US energy goes into non-residential buildings.  Gas for heating is about 60% of energy used in a building  Gas for heating is at least 25% of total energy used in the US. Heat Generation System Heat Disposal System What's Wrong With This Picture? Keep the heat IN the system Don't run main plant equipment until necessary ! Less rejected heat Less gas consumption High Temp >160F with conventional boilers Hydronic heating... condensing style modular boilers. The entire heating system... designed for low temperature water, recommend maximum temperature of 135ºF.

348

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

349

Heat Integration and Heat Recovery at a Large Chemical Manufacturing Plant  

E-Print Network (OSTI)

in the hydrogenation process. The hydrogenation process uses a catalyst to react the purified phenol with hydrogen, forming a mixture of cyclohexanone and cyclohexanol. The reaction is exothermic and is cooled with water to control the rate of reaction... Process Heat Recovery The process heat recovery opportunity was identified in the hydrogenation process. The hydrogenation process contains an exothermic reaction which is cooled with water to control the rate of reaction. The heated water...

Togna, K .A.

2012-01-01T23:59:59.000Z

350

Light weight and economical exhaust heat exchanger for waste heat recovery using mixed radiant and convective heat transfer  

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

A hybrid heat exchanger is designed to keep highly stressed materials around the working fluid at a moderate temperature so that it can operate at higher working fluid pressure.

351

DCO Operations Interesting Statistics  

E-Print Network (OSTI)

DCO Operations Interesting Statistics 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120 Chart by: HANDS DOWN SOFTWARE, www.handsdownsoftware.com 1.00 0.95 0.90 0.85 0.80 0.75 0.70 0.65 0.60 0 is annotated with the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE

352

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

353

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

354

Ultra high vacuum heating and rotating specimen stage  

DOE Patents (OSTI)

A heating and rotating specimen stage provides for simultaneous specimen heating and rotating. The stage is ideally suited for operation in ultrahigh vacuum (1.times.10.sup.-9 torr or less), but is useful at atmosphere and in pressurized systems as well. A specimen is placed on a specimen holder that is attached to a heater that, in turn, is attached to a top housing. The top housing is rotated relative to a bottom housing and electrically connected thereto by electrically conductive brushes. This stage is made of materials that are compatible with UHV, able to withstand high temperatures, possess low outgassing rates, are gall and seize resistant, and are able to carry substantial electrical loading without overheating.

Coombs, III, Arthur W. (Patterson, CA)

1995-01-01T23:59:59.000Z

355

Ultra high vacuum heating and rotating specimen stage  

DOE Patents (OSTI)

A heating and rotating specimen stage provides for simultaneous specimen heating and rotating. The stage is ideally suited for operation in ultrahigh vacuum (1{times}10{sup {minus}9} torr or less), but is useful at atmosphere and in pressurized systems as well. A specimen is placed on a specimen holder that is attached to a heater that, in turn, is attached to a top housing. The top housing is rotated relative to a bottom housing and electrically connected thereto by electrically conductive brushes. This stage is made of materials that are compatible with UHV, able to withstand high temperatures, possess low outgassing rates, are gall and seize resistant, and are able to carry substantial electrical loading without overheating. 5 figs.

Coombs, A.W. III

1995-05-02T23:59:59.000Z

356

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

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

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

357

Heat transport system, method and material  

DOE Patents (OSTI)

A heat transport system, method and composite material are disclosed in which a plurality of hollow spherical shells or microspheres having an outside diameter of less than or equal to 500 microns are encapsulated or embedded within a bulk material. Each shell has captured therein a volatile working fluid, such that each shell operates as a microsized heat pipe for conducting heat through the composite structure. 1 fig.

Musinski, D.L.

1987-04-28T23:59:59.000Z

358

Guide to Combined Heat and Power Systems for Boiler Owners and...  

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

Guide to Combined Heat and Power Systems for Boiler Owners and Operators, July 2004 Guide to Combined Heat and Power Systems for Boiler Owners and Operators, July 2004 Many owners...

359

Assessing the Thermal Environmental Impacts of an Groundwater Heat Pump in Southeastern Washington State  

SciTech Connect

A thermal analysis of a large-scale (e.g., 1900 gpm), open-loop ground source heat pump (GSHP) installed on the Pacific Northwest National Laboratory (PNNL) campus in southeastern Washington State has been performed using a numerical modeling approach. Water temperature increases at the upgradient extraction wells in the system and at the downgradient Columbia River are potential concerns, especially since heat rejection to the subsurface will occur year-round. Hence, thermal impacts of the open-loop GSHP were investigated to identify operational scenarios that minimized downgradient environmental impacts at the river, and upgradient temperature drift at the production wells. Simulations examined the sensitivity of the system to variations in pumping rates and injected water temperatures, as well as to hydraulic conductivity estimates of the aquifer. Results demonstrated that both downgradient and upgradient thermal impacts were more sensitive to injection flow rates than estimates of hydraulic conductivity. Higher injection rates at lower temperatures resulted in higher temperature increases at the extraction wells but lower increases at the river. Conversely, lower pumping rates and higher injected water temperatures resulted in a smaller temperature increase at the extraction wells, but higher increases at the river. The scenario with lower pumping rates is operationally more efficient, but does increase the likelihood of a thermal plume discharging into the Columbia River. However, this impact would be mitigated by mixing within the hyporheic zone and the Columbia River. The impact under current operational conditions is negligible, but future increases in heat rejection could require a compromise between maximizing operational efficiency and minimizing temperature increases at the shoreline.

Freedman, Vicky L.; Waichler, Scott R.; Mackley, Rob D.; Horner, Jacob A.

2012-04-01T23:59:59.000Z

360

Analysis of cross-flow mixed convection with applications to building heat transfer  

SciTech Connect

A numerical simulation model has been developed for partial enclosure with restricted inlet and outlet simulating the building fluid flow and heat transfer scenario. Computed results are presented for a number of geometric configurations over a wide range of Reynolds and Rayleigh numbers and validated with available experimental data. The physical processes were modeled by solving equations for the conservation of mass, momentum, and energy with appropriate boundary conditions. The properties of the fluid were assumed to remain approximately constant over the range of operation and the buoyancy was incorporated using the Boussinesq approximation. The k-{var_epsilon} model was used for the simulation of turbulence. The computed results included the local velocity and temperature and the variation of local heat transfer coefficient along the heated side wall. Computed results showed excellent agreement with experimental data. The flow pattern within the enclosure was found to be quite complex in nature and consisted of a core flow due to forced convection near the central region of the enclosure and strong buoyancy induced flow near the heated side walls. It was found that as the flow rate through the enclosure increased, the enhancement of heat transfer above that for natural convection alone, also increased. The variation of the local heat transfer coefficient over the heated surface was found to be strongly affected by the recirculation of portions of the forced flow within the enclosure as well as the impingement to or separation of flow from the side walls in some regions.

Gao, S.; Rahman, M.M.

1999-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "operating heat rate" 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

Magnetohydrodynamic power generation, electromagnetic pumps, heat pipes, and thermionic convertors  

SciTech Connect

The basic principles of operation, components, and design of MHD generators, electromagnetic pumps, heat pipes and thermionic converters are described. 66 references. (WHK)

Pierson, E.S.; Bonyhady, K.A.; Dunn, P.F.; Nathenson, R.D.; Uherka, K.L.

1984-01-01T23:59:59.000Z

362

Mapping Geothermal Heat Flow and Existing Plants | Department...  

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

resources make up most of the current geothermal operating plants in the United States. Power generation comes from drawing heat from the fluid found naturally deep below the...

363

Enhanced Building Operation Using "Operation Diagnostics" - A Case Study  

E-Print Network (OSTI)

the utility into hot water. They are lo- cated in a central heating plant room in the basement. The distribution system maintains static heating (of- fices south-west and offices north-east), heating coils of the AHUs, as well as central domestic hot... the dynamic operation of systems regarding reduced energy con- sumption and/or improved comfort. Available Data Base and Data Quality Data from the BAS has been recorded since Spring 2004. Due to limited capacity of the network only 160 of the 3200...

Baumann, O.

2005-01-01T23:59:59.000Z

364

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

365

NUMERICAL SIMULATION OF HEAT TRANSFER AND PRESSURE DROP IN PLATE HEAT EXCHANGERS USING FLUENT AS CFD TOOL.  

E-Print Network (OSTI)

??Corrugated walls are commonly used as passive devices for heat and mass transfer enhancement, being most effective in applications operated at transitional and turbulent Reynolds (more)

EGEREGOR, DAFE

2008-01-01T23:59:59.000Z

366

Thermohydraulic Simulation of Heat Exchanger Networks  

Science Journals Connector (OSTI)

The determination of network temperatures is carried out together with the evaluation of flow rates and pressures along the network, considering head losses in heat exchangers and associated piping. ... The HEN responsible to distribute cooling water in an industrial unit is composed by three heat exchangers in parallel. ... However, the cooling water distribution among the three exchangers presents a considerable unbalance, where heat exchanger E-101 receives much less cooling water than the design specification. ...

Viviane B. G. Tavares; Eduardo M. Queiroz; Andre? L. H. Costa

2010-04-26T23:59:59.000Z

367

VARIABLE FIRING RATE OIL BURNER USING PULSE FUEL FLOW CONTROL.  

SciTech Connect

The residential oil burner market is currently dominated by the pressure-atomized retention head burner, which has an excellent reputation for reliability and efficiency. In this burner, oil is delivered to a fuel nozzle at pressures from 100 to 150 psi. In addition, to atomizing the fuel, the small, carefully controlled size of the nozzle exit orifice serves to control the burner firing rate. Burners of this type are currently available at firing rates of more than 0.5 gallons-per-hour (70,000 Btu/hr). Nozzles have been made for lower firing rates, but experience has shown that such nozzles suffer rapid fouling of the necessarily small passages, leading to bad spray patterns and poor combustion performance. Also, traditionally burners and the nozzles are oversized to exceed the maximum demand. Typically, this is figured as follows. The heating load of the house on the coldest day for the location is considered to define the maximum heat load. The contractor or installer adds to this to provide a safety margin and for future expansion of the house. If the unit is a boiler that provides domestic hot water through the use of a tankless heating coil, the burner capacity is further increased. On the contrary, for a majority of the time, the heating system is satisfying a much smaller load, as only rarely do all these demands add up. Consequently, the average output of the heating system has to be much less than the design capacity and this is accomplished by start and stop cycling operation of the system so that the time-averaged output equals the demand. However, this has been demonstrated to lead to overall efficiencies lower than the steady-state efficiency. Therefore, the two main reasons for the current practice of using oil burners much larger than necessary for space heating are the unavailability of reliable low firing rate oil burners and the desire to assure adequate input rate for short duration, high draw domestic hot water loads. One approach to solve this problem is to develop a burner, which can operate at two firing rates, with the lower rate being significantly lower than 0.5 gallons per hour. This paper describes the initial results of adopting this approach through a pulsed flow nozzle. It has been shown that the concept of flow modulation with a small solenoid valve is feasible. Especially in the second configuration tested, where the Lee valve was integrated with the nozzle, reasonable modulation in flow of the order of 1.7 could be achieved. For this first prototype, the combustion performance is still not quite satisfactory. Improvements in operation, for example by providing a sharp and positive shut-off so that there is no flow under low pressures with consequent poor atomization could lead to better combustion performance. This could be achieved by using nozzles that have shut off or check valves for example. It is recommended that more work in cooperation with the valve manufacturer could produce a technically viable system. Marketability is of course a far more complex problem to be addressed once a technically viable product is available.

KRISHNA,C.R.; BUTCHER,T.A.; KAMATH,B.R.

2004-10-01T23:59:59.000Z

368

OPERATIONS (OPS)  

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

OPS) OPS) OBJECTIVE OPS.1 The formality and discipline of operations is adequate to conduct work safely and programs are in place to maintain this formality and discipline. (CR 13) Scope: The Conduct of Operations Program was evaluated during the recent KE Basin FTS ORR and was found to be adequately implemented. Based on this result and the subsequent program enhancements, the scope of the review is to be limited to the SWS operating and maintenance evolutions. Criteria * Programmatic elements of conduct of operations are in place for SWS operations. (DOE Order 5480.19) * The SWS operations personnel adequately demonstrate the principles of conduct of operations requirements during the shift performance period. (DOE Order 5480.19)

369

Determining window solar heat gain coefficient  

SciTech Connect

The solar heat gain characteristics of fenestration systems impact daytime building energy performance, occupant comfort and utility load demands. A measure of the fraction of available solar energy entering a building interior per unit window area is defined as the solar heat gain coefficient (SHGC). Together with a window's thermal transmittance (U-value), the SHGC is used to compare fenestration products, and it allows for the calculation of energy rating number and annual energy performance. The need to measure and compared advances in window technology has led to the development of experimental and analytical methods for the determination of SHGC performance. Several test facilities currently or previously capable of performing SHGC measurements exist worldwide. Results experimentally determined using these facilities have provided design data for handbook tables, and have been instrumental in the development and validation of predictive analytical methods and computer simulation tools. However, these facilities have operated without a standard test procedure for SHGC performance. Consequently, recent efforts have been focused on developing consensus test procedures for the evaluation of window energy performance.

Harrison, S.J.; Wonderen, S.J. van (Queen's Univ., Kingston, Ontario (Canada). Solar Calorimetry Lab.)

1994-08-01T23:59:59.000Z

370

Geothermal home heating facilities, Green Valley Estates, Fernley, Nevada  

SciTech Connect

A housing development to be located at Fernley, Nevada, about thirty miles east of Reno, is in an area of known geothermal water. The practicality of heating these homes with this water, as an alternative to heating with natural gas, has been investigated. A preliminary engineering design of a geothermal system was developed. This design permitted capital and operating cost to be estimated and a financial evaluation to be made. Two cases were investigated. The Base Case provides facilities for heating a tract of 371 houses. The Alternate Case adds another tract of 371 for a total of 742 houses. Geothermal water is to be provided by two wells and the used water reinjected into a third well. The Base Case has a rate of return on capital investment of 13.0 percent before taxes. The Alternate Case has a rate of return of 16.5 percent before taxes. The Alternate Case has a more favorable return due primarily to the assumption that each well has the capacity to produce 800 gpm of geothermal water. This is enough to provide for the additional 371 houses in the Alternate Case without an additional well. (MHR)

Not Available

1980-12-31T23:59:59.000Z

371

Conventional and advanced exergoeconomic analyses of geothermal district heating systems  

Science Journals Connector (OSTI)

Abstract The present study deals with analyzing, assessing and comparing conventional and advanced exergoeconomic analyses to identify the direction and potential for energy savings of a geothermal district heating system in future conditions/projections. As a real case study, the Afyon geothermal district heating system in Afyonkarahisar, Turkey, is considered while its actual operational thermal data on 8 February 2011 are utilized in the analysis, which is based on the specific exergy costing method. In this study for the first time, based on the concepts of avoidable/unavoidable and endogenous/exogenous parts, cost rates associated with both exergy destruction and capital investment of the geothermal district heating system are determined first, and the obtained results are then evaluated. The results indicate that the internal design changes play a more essential role in determining the cost of each component. The cost rate of unavoidable part within the components of the system is lower than that of the avoidable one. For the overall system, the value for the conventional exergoeconomic factor is determined to be 5.53% while that for the modified one is calculated to be 9.49%. As a result, the advanced exergoeconomic analysis makes more sense given the additional information in splitting process of the components.

Ali Keeba?; Arif Hepbasli

2014-01-01T23:59:59.000Z

372

Unique Challenges in the Design and Operation Philosophy of Solar Thermal Power Plants  

Science Journals Connector (OSTI)

Abstract Solar thermal power plant design and operation philosophy involves unique challenges as compared to design of conventional thermal power plants. The solar receiver operation should be able to absorb maximum solar load during transient events like daily start-up and shut-down. This requires aggressive ramp rates for transient operation of the power plant. However, the component and system level limitations must be considered in formulating these modes of operation and ramp rates. A solar receiver which usually receives heat from heliostats is designed to receive high heat flux to operate at high temperature and pressure during daytime. However, during night-time the receiver receives no heat flux and is losing heat to the environment. Day-night cyclic operation of a solar thermal power plant induces thermal cycles in the solar receiver pressure parts. Since solar receiver tubes are not insulated, the amplitude of thermal cycling is significant and needs to be addressed with proper tools and design approach. Besides, higher plant cycle efficiency requires higher operating temperature and pressure of a solar receiver, further increasing the amplitude of thermal cycling. The system level and component level response to these day-night cycles has a significant impact on modes of operation as well as on the life usage of various components. It also affects the design, specifications and operation of various plant level components. The solar thermal power plant design and operation process is optimized by having a system level thermal-hydraulics model for the solar receiver to simulate the transient start-up and shut-down events. Since all of the major components of the system are included in the model, it reflects the transient response of each of the components on each other and on the overall system. This simulation can be used to generate input conditions for component level life usage analysis. The component level life usage analysis is done using the finite-element method. The component level life usage analysis determines the permissible ramp rates. The thermal-hydraulics dynamic simulation outlines the operational philosophy of the system.

R. Terdalkar; H. Qian; G. Ye

2014-01-01T23:59:59.000Z

373

Multifamily Individual Heating and Ventilation Systems, Lawrence...  

Energy Savers (EERE)

each apartment were much higher than the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) 62.2 rate; an extensive system of ductwork, smoke and...

374

BCP Annual Rate Process  

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

2013 BCP Annual Rate Process 2013 BCP Annual Rate Process Informal Process Rate Activity Schedule (doc) Informal Customer Meeting Thursday March 6, 2013 at 10:30 A.M. Conf Rms 3&4 Informal Customer Meeting Presentation (Pdf) PRS Executive Summary (Mar 07, 2013) (Pdf) FY2014 Final Ten Year Operating Plan PRS Executive Summary (PDF) FORM for Foreign Visits (doc) Formal Process Initial Federal Register Notice (pdf) Public Information Forum March 27,2013 at 10:30 A.M. Conf Rms3&4 Customer Meeting Presentation PIF Presentation (PPT) Presentation Details (pdf) Reclamation Fund Status Report PIF PRS Executive Summary (pdf) PIF Transcripts (PDF) Visitor Center Cost Analysis Questions - Responses Public Comment Forum April 10, 2013 at 10:30 A.M. Conf Rms3&4 PCF Transcripts Customer Letters

375

Quantifying Combined Heat and Power (CHP) activity  

Science Journals Connector (OSTI)

In CHP plants without heat rejection facilities power, output is complementary to the recovery of heat, and all activity is cogeneration. CHP plants with heat rejection facilities can operate a mix of cogeneration and condensing activities. Quantifying the energy flows of both activities properly requires knowledge of the design power-to-heat ratios of the CHP processes (steam and gas turbines, combustion engines). The ratios may be multiple, non-linear or extend into the virtual domain of the production possibility sets of the plants. Quantifying cogeneration in CCGT plants reveals a definition conflict but consistent solutions are available.

Aviel Verbruggen

2007-01-01T23:59:59.000Z

376

Exergoeconomic evaluation on the optimum heating circuit system of Simav geothermal district heating system  

Science Journals Connector (OSTI)

Simav is one of the most important 15 geothermal areas in Turkey. It has several geothermal resources with the mass flow rate ranging from 35 to 72kg/s and temperature from 88 to 148C. Hence, these geothermal resources are available to use for several purposes, such as electricity generation, district heating, greenhouse heating, and balneological purposes. In Simav, the 5000 residences are heated by a district heating system in which these geothermal resources are used. Beside this, a greenhouse area of 225,000m2 is also heated by geothermal. In this study, the working conditions of the Simav geothermal district heating system have been optimized. In this paper, the main characteristics of the system have been presented and the impact of the parameters of heating circuit on the system are investigated by the means of energy, exergy, and life cycle cost (LCC) concepts. As a result, the optimum heating circuit has been determined as 60/49C.

Oguz Arslan; M.Arif Ozgur; Ramazan Kose; Abtullah Tugcu

2009-01-01T23:59:59.000Z

377

Control Dewar Subcooler Heat Exchanger Calculations  

SciTech Connect

The calculations done to size the control dewar subcooler were done to obtain a sufficient subcooler size based on some conservative assumptions. The final subcooler design proposed in the design report will work even better because (1) It has more tubing length, and (2) will have already subcooled liquid at the inlet due to the transfer line design. The subcooler design described in the 'Design Report of the 2 Tesla Superconducting Solenoid for the Fermilab D0 Detector Upgrade' is the final design proposed. A short description of this design follows. The subcooler is constructed of 0.50-inch OD copper tubing with 1.0-inch diameter fins. It has ten and one half spirals at a 11.375-inch centerline diameter to provide 31 feet of tubing length. The liquid helium supply for the solenoid flows through the subcooler and then is expanded through a J-T valve. The subcooler spirals are immersed in the return two phase helium process stream. The return stream is directed over the finned tubing by an annulus created by a 10-inch pipe inside a 12-inch pipe. The transfer line from the refrigerator to the control dewar is constructed such that the liquid helium supply tube is in the refrigerator return stream, thereby subcooling the liquid up to the point where the u-tubes connect the transfer line to the control dewar. The subcooler within the control dewar will remove the heat picked up in the helium supply u-tube/bayonets. The attached subcooler/heat exchanger calculations were done neglecting any subcooling in the transfer line. All heat picked up in the transfer line from the refrigerator storage dewar to the control dewar is absorbed by the supply stream. The subcooler was sized such that the two phase supply fluid is subcooled at 1.7 atm pressure and when expanded through a JT valve to 1.45 atm pressure it is at a saturated liquid state. The calculations apply during steady state operation and at a flow rate of 16 g/s. The analysis of the heat exchanger was broken into two parts relating to the heat transfer mode taking place. The first part is considered the condensing part in which the helium supply stream is changed from two phase fluid to one phase liquid. The second part is the subcooling part where the liquid temperature is lowered, i.e.. subcooled. A summary of the calculations and results appears on the next page. The raw calculations follow the summary.

Rucinski, R.; /Fermilab

1993-10-04T23:59:59.000Z

378

SPEAR Operations  

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

Interface 1113 N. Kurita J. Langton Vacuum TSP's 1120 J. Corbett A. Terebilo MATLAB Applications - Basics 1121 F. Rafael Booster Kicker Upgrade, Operation Manual 1121...

379

operations center  

National Nuclear Security Administration (NNSA)

1%2A en Operations Center http:nnsa.energy.govaboutusourprogramsemergencyoperationscounterterrorismoperationscenter

...

380

Floatable solar heat modules  

SciTech Connect

A floating solar heat module for swimming pools comprises a solid surface for conducting heat from the sun's rays to the water and further includes a solid heat storage member for continual heating even during the night. A float is included to maintain the solar heat module on the surface of the pool. The solid heat storage medium is a rolled metal disk which is sandwiched between top and bottom heat conducting plates, the top plate receiving the heat of the sun's rays through a transparent top panel and the bottom plate transferring the heat conducted through the top plate and rolled disk to the water.

Ricks, J.W.

1981-09-29T23:59:59.000Z

Note: This page contains sample records for the topic "operating heat rate" 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

Materials, Turbomachinery and Heat Exchangers for Supercritical CO2 Systems  

SciTech Connect

The objective of this project is to produce the necessary data to evaluate the performance of the supercritical carbon dioxide cycle. The activities include a study of materials compatibility of various alloys at high temperatures, the heat transfer and pressure drop in compact heat exchanger units, and turbomachinery issues, primarily leakage rates through dynamic seals. This experimental work will serve as a test bed for model development and design calculations, and will help define further tests necessary to develop high-efficiency power conversion cycles for use on a variety of reactor designs, including the sodium fast reactor (SFR) and very high-temperature gas reactor (VHTR). The research will be broken into three separate tasks. The first task deals with the analysis of materials related to the high-temperature S-CO{sub 2} Brayton cycle. The most taxing materials issues with regard to the cycle are associated with the high temperatures in the reactor side heat exchanger and in the high-temperature turbine. The system could experience pressures as high as 20MPa and temperatures as high as 650C. The second task deals with optimization of the heat exchangers required by the S-CO{sub 2} cycle; the S-CO{sub 2} flow passages in these heat exchangers are required whether the cycle is coupled with a VHTR or an SFR. At least three heat exchangers will be required: the pre-cooler before compression, the recuperator, and the heat exchanger that interfaces with the reactor coolant. Each of these heat exchangers is unique and must be optimized separately. The most challenging heat exchanger is likely the pre-cooler, as there is only about a 40C temperature change but it operates close to the CO{sub 2} critical point, therefore inducing substantial changes in properties. The proposed research will focus on this most challenging component. The third task examines seal leakage through various dynamic seal designs under the conditions expected in the S-CO{sub 2} cycle, including supercritical, choked, and two-phase flow conditions.

Mark Anderson; Greg Nellis; Michael Corradini

2012-10-19T23:59:59.000Z

382

Estimates of heat flow from Cenozoic seafloor using global depth and age data  

E-Print Network (OSTI)

-independent estimate of the total heat output of Cenozoic seafloor is 18.6 to 20.5 TW, which leads to a global output: Oceanic heat flow; Global heat budget; Subsidence rate 1. Introduction The total heat output of the EarthEstimates of heat flow from Cenozoic seafloor using global depth and age data Meng Wei , David

Sandwell, David T.

383

Dynamic modeling and optimal control strategy of waste heat recovery Organic Rankine Cycles  

Science Journals Connector (OSTI)

Organic Rankine Cycles (ORCs) are particularly suitable for recovering energy from low-grade heat sources. This paper describes the behavior of a small-scale ORC used to recover energy from a variable flow rate and temperature waste heat source. A traditional static model is unable to predict transient behavior in a cycle with a varying thermal source, whereas this capability is essential for simulating an appropriate cycle control strategy during part-load operation and start and stop procedures. A dynamic model of the ORC is therefore proposed focusing specifically on the time-varying performance of the heat exchangers, the dynamics of the other components being of minor importance. Three different control strategies are proposed and compared. The simulation results show that a model predictive control strategy based on the steady-state optimization of the cycle under various conditions is the one showing the best results.

Sylvain Quoilin; Richard Aumann; Andreas Grill; Andreas Schuster; Vincent Lemort; Hartmut Spliethoff

2011-01-01T23:59:59.000Z

384

NREL Documents Efficiency of Mini-Split Heat Pumps (Fact Sheet)  

SciTech Connect

A new report delivers mini-split heat pump (MSHP) performance data for use in whole-building simulation tools. Mini-split heat pumps (MSHPs) are highly efficient refrigerant-based air conditioning and heating systems that permit room-by-room conditioning and control in homes. Because of their size, efficiency, and price, MSHPs are very popular overseas and are gaining market share in energy-efficient home upgrades in the United States. They are a good option for retrofitting older homes that lack ductwork. To evaluate MSHP cost effectiveness and performance in U.S. homes, National Renewable Energy Laboratory (NREL) researchers are studying these systems in the laboratory, simulated buildings, and field test settings. A new NREL report describes an innovative laboratory approach to testing MSHPs and includes experimental performance maps for use in whole-building simulation tools. Most public information on MSHP performance is provided by equipment manufacturers, and is typically limited to performance at a single operating speed for heating and cooling. Mini-split heat pumps use variable speed components that spin up and down to continuously meet the heating or cooling need, significantly improving a system's operating efficiency. Measuring that efficiency in a laboratory is challenging and required new approaches to performance testing. NREL researchers worked with colleagues at Purdue University's Herrick Labs and Ecotope, Inc. to refine and apply this new approach to a suite of MSHP products. Researchers measured the performance of two MSHPs across a variety of operating conditions, which allowed, for the first time, development of accurate building simulation MSHP models. In the laboratory tests, researchers found that both MSHPs achieved manufacturer-reported performance at rating conditions. However, at other temperature and humidity conditions, the heat pumps capacity ranged from 40% above to 54% below the manufacturer-reported values. Knowing how performance varies is critical in order to reasonably estimate annual energy consumption of a MSHP, and to compare MSHPs to other heating and cooling options. Mini-split heat pump efficiency (COP) was seen to significantly exceed rated efficiency at low compressor speeds-a very important effect.

Not Available

2012-06-01T23:59:59.000Z

385

Thermoeconomic Analysis of a Solar Heat-Pump System  

E-Print Network (OSTI)

This paper introduces a solar energy heat-pump system and analyzes the thermoeconomics. The results show that the solar energy heat-pump system can be operated in different modes and used for room heating in winter and cooling in summer and...

Gao, Y.; Wang, S.

2006-01-01T23:59:59.000Z

386

Methods for microwave heat treatment of manufactured components  

DOE Patents (OSTI)

An apparatus for heat treating manufactured components using microwave energy and microwave susceptor material. Heat treating medium such as eutectic salts may be employed. A fluidized bed introduces process gases which may include carburizing or nitriding gases. The process may be operated in a batch mode or continuous process mode. A microwave heating probe may be used to restart a frozen eutectic salt bath.

Ripley, Edward B. (Knoxville, TN)

2010-08-03T23:59:59.000Z

387

Heat Pump for High School Heat Recovery  

E-Print Network (OSTI)

ICEBO2006, Shenzhen, China Renewable Energy Resources and a Greener Future Vol.VIII-12-1 Heat Pump for High School Bathroom Heat Recovery Kunrong Huang Hanqing Wang Xiangjiang Zhou Associate professor Professor Professor School...

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

2006-01-01T23:59:59.000Z

388

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...

389

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

Open Energy Info (EERE)

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

390

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...

391

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...

392

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...

393

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,...

394

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

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

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...

395

Waste Heat Management Options for Improving Industrial Process Heating Systems  

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

This presentation covers typical sources of waste heat from process heating equipment, characteristics of waste heat streams, and options for recovery including Combined Heat and Power.

396

Guide to Geothermal Heat Pumps  

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

Geothermal Heat Pumps Work Using a heat exchanger, a geothermal heat pump can move heat from one space to another. In summer, the geothermal heat pump extracts heat from a building...

397

Federal Energy Management Program: Water Rate Escalations  

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

Rate Rate Escalations to someone by E-mail Share Federal Energy Management Program: Water Rate Escalations on Facebook Tweet about Federal Energy Management Program: Water Rate Escalations on Twitter Bookmark Federal Energy Management Program: Water Rate Escalations on Google Bookmark Federal Energy Management Program: Water Rate Escalations on Delicious Rank Federal Energy Management Program: Water Rate Escalations on Digg Find More places to share Federal Energy Management Program: Water Rate Escalations on AddThis.com... Sustainable Buildings & Campuses Operations & Maintenance Greenhouse Gases Water Efficiency Basics Federal Requirements Best Management Practices Analysis and Evaluation Water Rate Escalations Evaluation Service Contracts Case Studies Resources

398

AMBIPOLAR DIFFUSION HEATING IN TURBULENT SYSTEMS  

SciTech Connect

The temperature of the gas in molecular clouds is a key determinant of the characteristic mass of star formation. Ambipolar diffusion (AD) is considered one of the most important heating mechanisms in weakly ionized molecular clouds. In this work, we study the AD heating rate using two-fluid turbulence simulations and compare it with the overall heating rate due to turbulent dissipation. We find that for observed molecular clouds, which typically have Alfven Mach numbers of {approx}1 and AD Reynolds numbers of {approx}20, about 70% of the total turbulent dissipation is in the form of AD heating. AD has an important effect on the length scale where energy is dissipated: when AD heating is strong, most of the energy in the cascade is removed by ion-neutral drift, with a comparatively small amount of energy making it down to small scales. We derive a relation for the AD heating rate that describes the results of our simulations to within a factor of two. Turbulent dissipation, including AD heating, is generally less important than cosmic-ray heating in molecular clouds, although there is substantial scatter in both.

Li, Pak Shing [Astronomy Department, University of California, Berkeley, CA 94720 (United States); Myers, Andrew [Physics Department, University of California, Berkeley, CA 94720 (United States); McKee, Christopher F., E-mail: psli@astron.berkeley.edu, E-mail: atmyers@berkeley.edu, E-mail: cmckee@berkeley.edu [Physics Department and Astronomy Department, University of California, Berkeley, CA 94720 (United States)

2012-11-20T23:59:59.000Z

399

Ion Heating in the Dense Plasma Focus  

Science Journals Connector (OSTI)

The collapse phase of a dense plasma focus gun operating in deuterium was studied using streak photography and time resolved x?ray and neutron measuring techniques. The streak photographs showing the radial motion of the luminous front at various axial positions indicate a collapsing luminous front at the time of the current collapse followed by an expanding front and a recompression. The luminosity then disappears for a period of several hundred nanoseconds during which time the neutrons are emitted. Estimates of shock heating and magnetic compressional heating were made from the streak pictures and a calculation of plasma heating due to viscous forces arising from axial motion of the plasma was carried out. The effects of shock heating magnetic compressional heating and viscous heating are shown to be sufficient to produce an ion temperature of several kilovolts.

A. J. Toepfer; D. R. Smith; E. H. Beckner

1971-01-01T23:59:59.000Z

400

Dynamic modeling of an integrated air-to-air heat pump using Modelica  

Science Journals Connector (OSTI)

Heat pump systems have gained significant market shares in Europe recently. The control strategy is an asset for the efficient operation of these thermodynamic systems; especially with compact integrated components. The predictive control, which allows fast system stabilization, is based on the description of the system physical behavior. Thus, dynamic modeling is needed for the development of such control. The model has to represent the system response to usual external perturbations met during current operation such as the variation of air temperature and air mass flow rate. The aim of this paper is to present a dynamic model of a thermodynamic system developed in the Dymola environment, which is an object-oriented modeling environment. The heat-pump components are created separately as individual objects, and then connected to form the system. The model of each component is described and the responses to different perturbations are detailed. Simulation results are compared to test results in order to validate the model.

S. Mortada; A. Zoughaib; D. Clodic; C. Arzano-Daurelle

2012-01-01T23:59:59.000Z

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


401

Heat recovery and the economizer for HVAC systems  

SciTech Connect

This articles examines why a combined heat reclaim/economizer system with priority to heat reclaim operation is most likely to result in the least annual total HVAC energy. PC-based, hour-by-hour simulation programs evaluate annual HVAC energy requirements when using combined operation of heat reclaim and economizer cycle, while giving priority to operation of either one. These simulation programs also enable the design engineer to select the most viable heat reclaim and/or economizer system for any given type of HVAC system serving the building internal load level, building geographical location and other building/system variables.

Anantapantula, V.S. (Emerson Electric Co., St. Louis, MO (United States). Alco Controls Div.); Sauer, H.J. Jr. (Univ. of Missouri, Rolla, MO (United States))

1994-11-01T23:59:59.000Z

402

The Effect of Magnetic Turbulence Energy Spectra and Pickup Ions on the Heating of the  

E-Print Network (OSTI)

The Effect of Magnetic Turbulence Energy Spectra and Pickup Ions on the Heating of the Solar Wind C02101 (2010)], we have incorporated in the heating model the energy cascade rate based on Iroshnikov scale. Since in steady state, the heating rate is essentially the same as the energy cascade rate

Ng, Chung-Sang

403

Heat Integration Strategy for Economic Production of Combined Heat and Power from Biomass Waste  

Science Journals Connector (OSTI)

Heat Integration Strategy for Economic Production of Combined Heat and Power from Biomass Waste ... Dilution of hydrogen rich fuels resulting from coal or heavy hydrocarbon gasification processes with nitrogen prior to the entrance of the gas turbines may be desirable in precombustion carbon capture and storage (CCS) routes, in order to ensure safe operations of gas turbines. ...

Jhuma Sadhukhan; Kok Siew Ng; Nilay Shah; Howard J. Simons

2009-09-15T23:59:59.000Z

404

Experimental study on heat transfer to supercritical water flowing through tubes  

SciTech Connect

A test facility named SWAMUP (Supercritical Water Multi-Purpose Loop) has been constructed in Shanghai Jiao Tong Univ. to investigate heat transfer and pressure drop through tubes and rod bundles. SWAMUP is a closed loop with operating pressure up to 30 MPa, outlet-water temperature up to 550 deg. C, and mass flow rate up to 5 t/h. In this paper, experimental study has been carried out on heat transfer of supercritical water flowing vertically through tubes (ID=7.6 and 10 mm). A large number of test points in tubes has been obtained with a wide range of heat flux (200-1500 kw/m{sup 2}) and mass flux (450-2000 kg/m{sup 2}s). Test results showed that heat transfer deterioration (HTD) caused by buoyancy effect only appears in upward flow and HTD caused by acceleration effect appears both in upward flow and downward flow. The heat transfer coefficients (HTC) produced in tube tests were compared with existing heat transfer correlations. (authors)

Zhao, M.; Gu, H.; Cheng, X. [School of Nuclear Science and Engineering, Shanghai Jiao Tong Univ. SJTU, 800 Dongchuan Road, Shanghai (China)

2012-07-01T23:59:59.000Z

405

A Megawatt-level 28z GHz Heating System For The National Spherical Torus Experiment Upgrade  

SciTech Connect

The National Spherical Torus Experiment Upgrade (NSTX-U) will operate at axial toroidal fields of < 1 T and plasma currents, Ip < 2 MA. The development of non-inductive (NI) plasmas is a major long-term research goal for NSTX-U. Time dependent numerical simulations of 28 GHz electron cyclotron (EC) heating of low density NI start-up plasmas generated by Coaxial Helicity Injection (CHI) in NSTX-U predict a significant and rapid increase of the central electron temperature (Te(0)) before the plasma becomes overdense. The increased Te(0) will significantly reduce the Ip decay rate of CHI plasmas, allowing the coupling of fast wave heating and neutral beam injection. A megawatt-level, 28 GHz electron heating system is planned for heating NI start-up plasmas in NSTX-U. In addition to EC heating of CHI start-up discharges, this system will be used for electron Bernstein wave (EBW) plasma start-up, and eventually for EBW heating and current drive during the Ip flattop.

Taylor, Gary [PPPL

2014-04-01T23:59:59.000Z

406

A solid?state solar?powered heat transfer device  

Science Journals Connector (OSTI)

A solar?powered solid?state heat transferdevice capable of operating in either a refrigeration or a heat?pump mode is proposed. The devices operation is based on the combined utilization of the photovoltaic and Peltier effects.

Milivoj Beli?; Joel I. Gersten

1979-01-01T23:59:59.000Z

407

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

408

An experimental study of heat pipe thermal management system with wet cooling method for lithium ion batteries  

Science Journals Connector (OSTI)

Abstract An effective battery thermal management (BTM) system is required for lithium-ion batteries to ensure a desirable operating temperature range with minimal temperature gradient, and thus to guarantee their high efficiency, long lifetime and great safety. In this paper, a heat pipe and wet cooling combined BTM system is developed to handle the thermal surge of lithium-ion batteries during high rate operations. The proposed BTM system relies on ultra-thin heat pipes which can efficiently transfer the heat from the battery sides to the cooling ends where the water evaporation process can rapidly dissipate the heat. Two sized battery packs, 3Ah and 8Ah, with different lengths of cooling ends are used and tested through a series high-intensity discharges in this study to examine the cooling effects of the combined BTM system, and its performance is compared with other four types of heat pipe involved BTM systems and natural convection cooling method. A combination of natural convection, fan cooling and wet cooling methods is also introduced to the heat pipe BTM system, which is able to control the temperature of battery pack in an appropriate temperature range with the minimum cost of energy and water spray.

Rui Zhao; Junjie Gu; Jie Liu

2015-01-01T23:59:59.000Z

409

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

410

Total Space Heat-  

Annual Energy Outlook 2012 (EIA)

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...

411

ARM - Heat Index Calculations  

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

FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans Heat Index Calculations Heat Index is an index that combines air temperature and relative...

412

Optimal operation of simple vapour compression cycles  

E-Print Network (OSTI)

to a high temperature level. The first application, in 1834, was cooling to produce ice for storage of food for heating and cooling are widely used in many applications and their power ranges from less than 1 k to operate in both heating and cooling mode. A schematic drawing of a simple cycle is shown in Figure 1

Skogestad, Sigurd

413

Heat flux solarimeter  

SciTech Connect

The solarimeter presented in this work is easy to assemble. It is calibrated and its performance is validated by means of Hottel's method. Finally, the curves obtained with this solarimeter are compared to the ones obtained with a commercial solarimeter. This device is based on the evaluation of the heat flow in a metal rod. In consequence, measurements are not affected by ambient temperature variations. On the other hand, there is a linear relationship between the temperatures measured at the rod ends and the incident radiation, as can be concluded both from the theory of its operation and the calibration lines obtained. The results obtained from the global irradiance measurements in the area of Los Polvorines (Buenos Aires Province), together with a preliminary evaluation of the solarimeter's response time, are presented in this work. (author)

Sartarelli, A.; Vera, S.; Cyrulies, E. [Instituto de Desarrollo Humano, Univ. Nac. de Gral. Sarmiento (IDH, UNGS), Los Polvorines (Argentina); Echarri, R. [Instituto de Desarrollo Humano, Univ. Nac. de Gral. Sarmiento (IDH, UNGS), Los Polvorines (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Samson, I. [INTEC (Instituto Tecnologico Santo Domingo), Santo Domingo (Dominican Republic)

2010-12-15T23:59:59.000Z

414

Electron Cyclotron Heating in a Non-Uniform Magnetic Field  

E-Print Network (OSTI)

Electron Cyclotron Heating in a Non-Uniform Magnetic Field by J.e. Sprott December 1968 Presented pulse. IN1RODUCTION Most previous theories of electron cyclotron resonance heating have dealt primarily will outline a simple theoretical model which can be used to estimate the electron cyclotron heating rate

Sprott, Julien Clinton

415

Confortable Performance: Retro-Commissioning Building Operations  

E-Print Network (OSTI)

troubleshooting ? New controls strategies ? Equipment schedule optimization ? Comfort improvements 7 ESL-IC-13-10-07 Proceedings of the 13th International Conference for Enhanced Building Operations, Montreal, Quebec, October 8-11, 2013 Tools ? Actuator... Operations, Montreal, Quebec, October 8-11, 2013 Example 1 ? Problem ? Monday morning ?too cold? complaints ? Solution ? Heating system start-up on Sunday at 2:00pm ? RCx Investigation ? Tenant MAU running 24x7 with no heat (space temperature...

Botan, L.

2013-01-01T23:59:59.000Z

416

ARM - Measurement - Sensible heat flux  

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

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

417

ARM - Measurement - Latent heat flux  

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

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

418

Design operators  

E-Print Network (OSTI)

Design operators is a thesis that investigates the nature and characteristics of the design process by examining the interaction of computation with architectural design. The effects of the introduction of these media in ...

Dritsas, Stylianos, 1978-

2004-01-01T23:59:59.000Z

419

Business Operations  

Office of Energy Efficiency and Renewable Energy (EERE)

The Office of Business Operations is the central organization for all Office of Energy Efficiency and Renewable Energy (EERE) business products, processes, and systems. The three main offices of...

420

Operating Costs  

Directives, Delegations, and Requirements

This chapter is focused on capital costs for conventional construction and environmental restoration and waste management projects and examines operating cost estimates to verify that all elements of the project have been considered and properly estimated.

1997-03-28T23:59:59.000Z

Note: This page contains sample records for the topic "operating heat rate" 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

Performance analysis of reciprocating regenerative magnetic heat pumping. Final report  

SciTech Connect

Transient flow phenomena in the regenerator tube of reciprocating magnetic heat pumps have been studied numerically and experimentally. In the numerical study, two approaches were taken: (1) solving the energy balance equations for fluid through a porous bed directly and (2) solving the Navier-Stokes equations with a buoyancy force term in the momentum equation. A flow thermal mixing problem was found in both approaches because of the piston-like motion of the regenerator tube that hinders the development of the temperature. The numerical study results show that a 45 K temperature span can be reached in 10 minutes of charge time through the use of a 7-Tesla magnetic field. Using the second numerical approach, temperature stratification in the regenerator fluid column was clearly indicated through temperature rasters. The study also calculates regenerator efficiency and energy delivery rates when heating load and cooling load are applied. Piecewise variation of the regenerator tube moving speed has been used in the present numerical study to control the mass flow rate, reduce thermal mixing of the flow and thus the regenerative losses. The gadolinium`s adiabatic temperature has been measured under 6.5 Tesla of magnet field and different of operating temperatures ranging from 285 K to 320 K. Three regenerative heat pumping tests have also been conducted based on the Reynolds number of the regenerator tube flow, namely Re=300, Re=450, and Re=750 without loads. Maximum temperature span are 12 & 11 K and 9 K for the case of Re=300, Re=450 and Re=750, respectively. Experimental data are in good agreement with the numerical calculation results, and have been used to calibrate the numerical results and to develop a design database for reciprocating-type room-temperature magnetic heat pumps.

Chen, D.T. [Oak Ridge Associated Universities, Inc., TN (United States); Murphy, R.W.; Mei, V.C.; Chen, F.C.; Lue, J.W.; Lubell, M.S. [Oak Ridge National Lab., TN (United States)

1994-02-01T23:59:59.000Z

422

Pressurized reactor system and a method of operating the same  

DOE Patents (OSTI)

A method and apparatus are provided for operating a pressurized reactor system in order to precisely control the temperature within a pressure vessel in order to minimize condensation of corrosive materials from gases on the surfaces of the pressure vessel or contained circulating fluidized bed reactor, and to prevent the temperature of the components from reaching a detrimentally high level, while at the same time allowing quick heating of the pressure vessel interior volume during start-up. Superatmospheric pressure gas is introduced from the first conduit into the fluidized bed reactor and heat derived reactions such as combustion and gassification are maintained in the reactor. Gas is exhausted from the reactor and pressure vessel through a second conduit. Gas is circulated from one part of the inside volume to another to control the temperature of the inside volume, such as by passing the gas through an exterior conduit which has a heat exchanger, control valve, blower and compressor associated therewith, or by causing natural convection flow of circulating gas within one or more generally vertically extending gas passages entirely within the pressure vessel (and containing heat exchangers, flow rate control valves, or the like therein). Preferably, inert gas is provided as a circulating gas, and the inert gas may also be used in emergency shut-down situations. In emergency shut-down reaction gas being supplied to the reactor is cut off, while inert gas from the interior gas volume of the pressure vessel is introduced into the reactor.

Isaksson, Juhani M. (Karhula, FI)

1996-01-01T23:59:59.000Z

423

Pressurized reactor system and a method of operating the same  

DOE Patents (OSTI)

A method and apparatus are provided for operating a pressurized reactor system in order to precisely control the temperature within a pressure vessel in order to minimize condensation of corrosive materials from gases on the surfaces of the pressure vessel or contained circulating fluidized bed reactor, and to prevent the temperature of the components from reaching a detrimentally high level, while at the same time allowing quick heating of the pressure vessel interior volume during start-up. Super-atmospheric pressure gas is introduced from the first conduit into the fluidized bed reactor and heat derived reactions such as combustion and gasification are maintained in the reactor. Gas is exhausted from the reactor and pressure vessel through a second conduit. Gas is circulated from one part of the inside volume to another to control the temperature of the inside volume, such as by passing the gas through an exterior conduit which has a heat exchanger, control valve, blower and compressor associated therewith, or by causing natural convection flow of circulating gas within one or more generally vertically extending gas passages entirely within the pressure vessel (and containing heat exchangers, flow rate control valves, or the like therein). Preferably, inert gas is provided as a circulating gas, and the inert gas may also be used in emergency shut-down situations. In emergency shut-down reaction gas being supplied to the reactor is cut off, while inert gas from the interior gas volume of the pressure vessel is introduced into the reactor. 2 figs.

Isaksson, J.M.

1996-06-18T23:59:59.000Z

424

Operation and performance of a low temperature Organic Rankine Cycle  

Science Journals Connector (OSTI)

Abstract The test and analysis of an Organic Rankine Cycle (ORC) with R123 as the working fluid were presented in this paper. A scroll expander was integrated in the system to generate work. The expander was connected with an AC dynamometer unit, which was used to control and measure the expander shaft torque and rotating speed. The conductive oil simulated the low grade heat source. Operation characteristics were compared between the heat source temperatures of 140C and 160C. The experiments were conducted by adjusting two independent parameters: the pumping frequency of the R123 pump and the shaft torque of the expander. The former parameter was directly related to the R123 mass flow rate and the later to the external load. The optimum system performance can be determined by these two parameters. The maximum measured shaft power and thermal efficiency were 2.35 kW and 6.39% at the heat source temperature of 140C, but they were 3.25 kW and 5.12% at the heat source temperature of 160C. This study identified that the measured shaft power was about 15-20% lower than the enthalpy determined values, and the pumping power of the organic fluid was 2-4 times higher than the enthalpy determined values. The enthalpy determined values were based on the local pressure and temperature sensor measurements.

Zheng Miao; Jinliang Xu; Xufei Yang; Jinhuang Zou

2014-01-01T23:59:59.000Z

425

Experimental study of an air-source heat pump for simultaneous heating and cooling Part 1: Basic concepts and performance verification  

E-Print Network (OSTI)

manufacturer. The operation of the high pressure control system, the transitions between heating, cooling, heating and cooling energies using the same electric energy input at the compressor. Chua et al. [31 Experimental study of an air-source heat pump for simultaneous heating and cooling ­ Part 1

Boyer, Edmond

426

Design and optimization of a downhole coaxial heat exchanger for an enhanced geothermal system (EGS)  

Science Journals Connector (OSTI)

The present study considers the design, performance analysis and optimization of a downhole coaxial heat exchanger for an enhanced geothermal system (EGS). The optimum mass flow rate of the geothermal fluid for minimum pumping power and maximum extracted heat energy was determined. In addition, the coaxial pipes of the downhole heat exchanger were sized based on the optimum geothermal mass flow rate and steady-state operation. Transient effect or time-dependent cooling of the Earth underground, and the optimum amount and size of perforations at the inner pipe entrance region to regulate the flow of the geothermal fluid were disregarded to simplify the analysis. The paper consists of an analytical and numerical thermodynamic optimization of a downhole coaxial heat exchanger used to extract the maximum possible energy from the Earth's deep underground (2km and deeper below the surface) for direct usage, and subject to a nearly linear increase in geothermal gradient with depth. The thermodynamic optimization process and entropy generation minimization (EGM) analysis were performed to minimize heat transfer and fluid friction irreversibilities. An optimum diameter ratio of the coaxial pipes for minimum pressure drop in both limits of the fully turbulent and laminar fully-developed flow regime was determined and observed to be nearly the same irrespective of the flow regime. Furthermore, an optimum geothermal mass flow rate and an optimum geometry of the downhole coaxial heat exchanger were determined for maximum net power output. Conducting an energetic and exergetic analysis to evaluate the performance of binary power cycle, higher Earth's temperature gradient and lower geofluid rejection temperatures were observed to yield maximum first- and second-law efficiencies.

P.J. Yekoladio; T. Bello-Ochende; J.P. Meyer

2013-01-01T23:59:59.000Z

427

Heat pump associations, alliances, and allies  

SciTech Connect

Associations, Alliances, and Allies, a seminar and workshop sponsored by the Electric Power Research Institute, was held in Memphis, Tennessee, April 10--11, 1991. The focus of the meeting was relationships forged between electric utilities and trade allies that sell residential heat pumps. one hundred and seven representatives of electric utilities, dealer/contractors, manufacturers, and consultants attended. Electric utility trade ally programs run the gamut from coop advertising to heat pump association to elaborate technician training programs. All utility participants recognize the important programs, since it is the trade ally who sells, installs, and services heat pumps, while it is the electric utility who gets blamed if the heat pumps fail to operate properly or are inefficient. Heat pumps are efficient and effective, but their efficiency and effectiveness depends critically upon the quality of installation and maintenance. A utility can thus help to ensure satisfied customers and can also help to achieve its own load shape objectives by working closely with its trade allies, the dealers, contractors, manufacturers, and distributors. Attendees spent the morning sessions of the two day meeting in plenary sessions, hearing about utility and dealer heat pump programs and issues. Afternoon roundtable discussions provided structured forums to discuss: Advertising; Heat pump association startup and operation; Rebates and incentives; Technician training school and centers; Installation inspection and dealer qualification; and Heat pump association training. These proceedings report on the papers presented in the morning plenary sessions and summarize the main points discussed in the afternoon workshops.

Not Available

1992-09-01T23:59:59.000Z

428

Water Heating Products and Services | Department of Energy  

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

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

429

Water Heating Products and Services | Department of Energy  

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

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

430

Effects of heat stress on mammalian reproduction  

Science Journals Connector (OSTI)

...University of Florida, , PO Box 110910...combustion of fuel stuffs to achieve a high metabolic rate (i.e. heat...to changes in energy balance and nutrient...on conception rate of dairy cattle...Hereford cattle in Florida. J. Anim. Sci...University of Florida, PO Box 110910...

2009-01-01T23:59:59.000Z

431

Realities of Chiller Plant Operation: Utility Impacts on Owner Operating  

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

Realities of Chiller Plant Operation: Utility Impacts on Owner Operating Realities of Chiller Plant Operation: Utility Impacts on Owner Operating Costs and Societal Environmental Issues Speaker(s): Don Aumann Date: March 21, 2000 - 12:00pm Location: Bldg. 90 Seminar Host/Point of Contact: Satkartar K. Kinney Don Aumann, a Senior Consultant from BKi in Oakland, will present an overview of two projects he completed for the electric utility industry. The first, a case study evaluation of a hybrid chiller plant in Jefferson City, Missouri, demonstrates the importance of carefully evaluating the impact of utility rate structures on plant operating costs. The building owner, another engineering consultant, and the local utility representatives were confused by the rates and missed an opportunity to cut chiller-plant operating costs by about 20%, totaling $15,000 per year. In

432

COSMIC RAY HEATING OF THE WARM IONIZED MEDIUM  

SciTech Connect

Observations of line ratios in the Milky Way's warm ionized medium suggest that photoionization is not the only heating mechanism present. For the additional heating to explain the discrepancy, it would have to have a weaker dependence on the gas density than the cooling rate, {Lambda}n{sub e}{sup 2}. Reynolds et al. suggested turbulent dissipation or magnetic field reconnection as possible heating sources. We investigate here the viability of MHD-wave mediated cosmic ray heating as a supplemental heating source. This heating rate depends on the gas density only through its linear dependence on the Alfven speed, which goes as n{sub e}{sup -1/2}. We show that, scaled to appropriate values of cosmic ray energy density, cosmic ray heating can be significant. Furthermore, this heating is stable to perturbations. These results should also apply to warm ionized gas in other galaxies.

Wiener, Joshua; Peng Oh, S. [Department of Physics, University of California, Santa Barbara, CA 93106 (United States)] [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Zweibel, Ellen G. [Departments of Astronomy and Physics, and Center for Magnetic Self-Organization, University of Wisconsin-Madison, Madison, WI 53706 (United States)] [Departments of Astronomy and Physics, and Center for Magnetic Self-Organization, University of Wisconsin-Madison, Madison, WI 53706 (United States)

2013-04-10T23:59:59.000Z

433

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

434

Thulium-170 heat source  

SciTech Connect

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

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

1990-09-06T23:59:59.000Z

435

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

436

FS: heat pump water heaters | The Better Buildings Alliance  

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

Food Service » Install a heat pump Food Service » Install a heat pump water heaterand reduce water heating energy up to 70% using the commercial heat pump water heater specificat Activities Technology Solutions Teams Lighting & Electrical Space Conditioning Plug & Process Loads Food Service Refrigeration Laboratories Energy Management & Information Systems Public Sector Teams Market Solutions Teams Install a heat pump water heaterand reduce water heating energy up to 70% using the commercial heat pump water heater specification The Food Service team developed a Commercial Heat Pump Water Heater Specification that can be used to reduce water heating energy by 70%. An older, electric resistance water heater (operated in a building with a hot water demand of 500 gallons a day) can cost more than $3,500 each year

437

Ductless, Mini-Split Heat Pumps | Department of Energy  

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

Ductless, Mini-Split Heat Pumps Ductless, Mini-Split Heat Pumps Ductless, Mini-Split Heat Pumps June 24, 2012 - 4:19pm Addthis What does this mean for me? You can take advantage of the fact that -- unlike earlier versions -- newer models of ductless mini-split heat pumps operate effectively in cold temperatures. If you are building an addition or doing a major remodel and your home does not have heating and cooling ducts, a ductless mini-split heat pump may be a cost-effective, energy-efficient choice. Ductless, mini-split-system heat pumps (mini splits) make good retrofit add-ons to houses with "non-ducted" heating systems, such as hydronic (hot water heat), radiant panels, and space heaters (wood, kerosene, propane). They can also be a good choice for room additions where extending or

438

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

E-Print Network (OSTI)

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

Kihm, IconKenneth David

439

Cooling and Clusters: When Is Heating Needed?  

E-Print Network (OSTI)

There are (at least) two unsolved problems concerning the current state of the thermal gas in clusters of galaxies. The first is identifying the source of the heating which offsets cooling in the centers of clusters with short cooling times (the ``cooling flow'' problem). The second is understanding the mechanism which boosts the entropy in cluster and group gas. Since both of these problems involve an unknown source of heating it is tempting to identify them with the same process, particular since AGN heating is observed to be operating at some level in a sample of well-observed ``cooling flow'' clusters. Here we show, using numerical simulations of cluster formation, that much of the gas ending up in clusters cools at high redshift and so the heating is also needed at high-redshift, well before the cluster forms. This indicates that the same process operating to solve the cooling flow problem may not also resolve the cluster entropy problem.

Greg L. Bryan; G. Mark Voit

2005-02-22T23:59:59.000Z

440

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

Note: This page contains sample records for the topic "operating heat rate" 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

An Experimental Study of Upward and Downward Flow of Supercritical Carbon Dioxide in a Straight Pipe Heat Exchanger with Constant Wall Heat Flux  

E-Print Network (OSTI)

An experimental analysis was conducted on a single circular tube heat exchanger using supercritical carbon dioxide as the working fluid. The heat exchanger was operated in two different orientations: vertically upward and downward. The experimental...

Umrigar, Eric Dara

2014-05-01T23:59:59.000Z

442

Heat Integrate Heat Engines in Process Plants  

E-Print Network (OSTI)

and refrigeration systems. In many instances these real heat engines may appear as a complex process consisting of flash vessels, heat exchangers, compressors, furnaces, etc. See Figure 18a, which shows a simplified diagram of a "steam Rankine cycle." How... and rejection profiles of the real machine. For example, the heat acceptance and re jection profiles for the steam Rankine cycle shown in Figure 18a have been drawn on T,H coordinates in Figure 18b. Thus providing we know the heat acceptance and rejection...

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

443

Waste Heat Recovery Power Generation with WOWGen  

E-Print Network (OSTI)

Waste Heat Recovery Power Generation with WOWGen? Business Overview WOW operates in the energy efficiency field - one of the fastest growing energy sectors in the world today. The two key products - WOWGen? and WOWClean? provide more... energy at cheaper cost and lower emissions. ? WOWGen? - Power Generation from Industrial Waste Heat ? WOWClean? - Multi Pollutant emission control system Current power generation technology uses only 35% of the energy in a fossil fuel...

Romero, M.

444

Transparent heat-spreader for optoelectronic applications  

DOE Patents (OSTI)

An optoelectronic cooling system is equally applicable to an LED collimator or a photovoltaic solar concentrator. A transparent fluid conveys heat from the optoelectronic chip to a hollow cover over the system aperture. The cooling system can keep a solar concentrator chip at the same temperature as found for a one-sun flat-plate solar cell. Natural convection or forced circulation can operate to convey heat from the chip to the cover.

Minano, Juan Carlos; Benitez, Pablo

2014-11-04T23:59:59.000Z

445

###Operating Principles published 411.pdf  

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

Analysis of operating principles with S-system models Yun Lee 1 , Po-Wei Chen 1 , Eberhard O. Voit ⇑ The Wallace H. Coulter Department of Biomedical Engineering, Georgia Tech and Emory University, 313 Ferst Drive, Suite 4103, Atlanta, GA 30332-0535, United States a r t i c l e i n f o Article history: Available online 4 March 2011 Keywords: Biochemical Systems Theory Design principle Heat stress Operating principle S-system Trehalose a b s t r a c t Operating principles address general questions regarding the response dynamics of biological systems as we observe or hypothesize them, in comparison to a priori equally valid alternatives. In analogy to design principles, the question arises: Why are some operating strategies encountered more frequently than others and in what sense might they be superior? It is at this point impossible to study operation prin- ciples in complete generality,

446

Heating and cooling of municipal buildings with waste heat from ground water  

SciTech Connect

The feasibility of using waste heat from municipal water wells to replace natural gas for heating of the City Hall, Fire Station, and Community Hall in Wilmer, Texas was studied. At present, the 120/sup 0/F well water is cooled by dissipating the excess heat through evaporative cooling towers before entering the distribution system. The objective of the study was to determine the pumping cycle of the well and determine the amount of available heat from the water for a specified period. This data were correlated with the heating and cooling demand of the City's buildings, and a conceptual heat recovery system will be prepared. The system will use part or all of the excess heat from the water to heat the buildings, thereby eliminating the use of natural gas. The proposed geothermal retrofit of the existing natural gas heating system is not economical because the savings in natural gas does not offset the capital cost of the new equipment and the annual operating and maintenance costs. The fuel savings and power costs are a virtual trade-off over the 25-year period. The installation and operation of the system was estimated to cost $105,000 for 25 years which is an unamortized expense. In conclusion, retrofitting the City of Wilmer's municipal buildings is not feasible based on the economic analysis and fiscal projections as presented.

Morgan, D.S.; Hochgraf, J.

1980-10-01T23:59:59.000Z

447

Substation Operation  

Science Journals Connector (OSTI)

... THIS book is intended to help the workman to understand the principles of substation operation. It is a good attempt at giving somewhat advanced technical knowledge in such ... ." We are told not to use water to put out a fire at a substation before the station has been made completely " dead." The reason given for this ...

1925-08-01T23:59:59.000Z

448

Economic assessment of geothermal district heating systems: A case study of BalcovaNarlidere, Turkey  

Science Journals Connector (OSTI)

Geothermal energy is an important renewable energy resource in Turkey. The aim of this research is to evaluate the BalcovaNarlidere geothermal district heating system from an economic perspective. The system is the largest one in Turkey in terms of heating capacity and located in Izmir. Although there are some assessments regarding energy and exergy analysis for the BalcovaNarlidere geothermal district heating system, an economic assessment was not performed, previously. The profitability of the investment is investigated by using internal rate of return method. Seven hundred and eighty different scenarios are developed in this assessment. In order to estimate the potential cash flows in the remaining project life, operating cost in 2002 is decreased and increased, alternatively, between 5% and 30% by 5% in each step, while monthly energy utilization price is changed between US$ 17 and 72 in those scenarios. The energy utilization prices are suggested according to zero IRR value for all scenarios due to the consideration of social and environmental concerns in this investment. It is found that, the proper monthly energy utilization price for a 100m2 household would be US$ 55.5 when the operating cost and heating capacity in 2002 were remained constant.

Berkan Erdogmus; Macit Toksoy; Baris Ozerdem; Niyazi Aksoy

2006-01-01T23:59:59.000Z

449

Electron Cyclotron Heating in RFP plasmas  

SciTech Connect

Reversed field pinches (RFP) plasmas are typically overdense ({omega}{sub pe}>{omega}{sub ce}) and thus not suitable for conventional electron cyclotron (EC) heating and current drive. In recent high plasma current discharges (I{sub p}>1.5 MA), however, the RFX-mod device was operated in underdense conditions ({omega}{sub pe}<{omega}{sub ce}) for the first time in an RFP. Thus, it is now possible to envisage heating the RFP plasma core by conventional EC at the 2nd harmonic, in the ordinary or extraordinary mode. We present a preliminary study of EC-heating feasibility in RFX-mod with the use of beam-tracing and full-wave codes. Although not competitive - as a heating system - with multi-MW Ohmic heating in an RFP, EC might be useful for perturbative transport studies, even at moderate power (hundreds of kW), and, more generally, for applications requiring localized power deposition.

Bilato, R.; Poli, E. [MPI fuer Plasmaphysik-Euratom Association Boltzmannstr. 2, D-85748 Garching (Germany); Volpe, F. [Department of Engineering Physics, University of Wisconsin, Madison, WI (United States); Koehn, A. [Institut fuer Plasmaforschung, Universitaet Stuttgart-Stuttgart (Germany); Cavazzana, R.; Paccagnella, R. [Consorzio RFX-Associazione EURATOM-ENEA sulla fusione-Padova (Italy); Farina, D. [IFP-CNR, EURATOM-ENEA-CNR Association-Milano (Italy)

2009-11-26T23:59:59.000Z

450

Buffalo district heating system design and construction  

SciTech Connect

This report addresses the introduction of district heating in Buffalo, NY from feasibility study to implementation. The reemergence of district heating in the US and associated advantages are reviewed. Advanced piping technology which has enabled district heating to compete economically with alternative technologies is summarized. Identification and analysis of the customer heat load considered in downtown Buffalo for the pilot system and future expansion is discussed. Various options for initiating construction of a district heating system were considered as exemplified by the configuration for the pilot system which was selected to serve five downtown buildings. A conceptual plan is presented which permits the system to expand in an economically viable manner. The report concludes with an economic analysis which simulates the operation and expansion of the system. 4 figs., 8 tabs.

Oliker, I.

1987-11-01T23:59:59.000Z

451

Energy Star Building Upgrade Manual Heating and Cooling  

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

9. Heating and 9. Heating and Cooling Revised January 2008 9.1 Overview 2 9.2 Central Cooling Systems 3 Chiller Plant Operations and Maintenance 4 Chiller Plant Retrofits 6 9.3 Central Heating Systems 10 Boiler System Operations and Maintenance 11 Boiler System Retrofits 11 Improving Furnace Efficiency 13 9.4 Unitary Systems 14 Packaged Rooftop Units 16 Split-System Packaged Units 18 Air-Source Heat Pumps 18 Ground-Source, Closed-Loop Heat Pumps 19 9.5 Additional Strategies 20 Air-Side Economizer 20 Energy Recovery 20 Desiccant Dehumidification 20 Night Precooling 21 Cool Storage 22 Evaporative Cooling 22 9.6 Summary 22 Bibliography 23 Glossary G-1 1 ENERGY STAR ® Building Manual ENERGY STAR ® Building Manual 9. Heating and Cooling 9.1 Overview Although heating and cooling systems provide a useful service by keeping occupants comfort-

452

Thermoelectric recovery of waste heat -- Case studies  

SciTech Connect

The use of waste heat as an energy source for thermoelectric generation largely removes the constraint for the wide scale application of this technology imposed by its relatively low conversion efficiency (typically about 5%). Paradoxically, in some parasitic applications, a low conversion efficiency can be viewed as a distinct advantage. However, commercially available thermoelectric modules are designed primarily for refrigerating applications and are less reliable when operated at elevated temperatures. Consequently, a major factor which determines the economic competitiveness of thermoelectric recovery of waste heat is the cost per watt divided by the mean-time between module failures. In this paper is reported the development of a waste, warm water powered thermoelectric generator, one target in a NEDO sponsored project to economically recover waste heat. As an application of this technology case studies are considered in which thermoelectric generators are operated in both active and parasitic modes to generate electrical power for a central heating system. It is concluded that, in applications when the supply of heat essentially is free as with waste heat, thermoelectrics can compete economically with conventional methods of electrical power generation. Also, in this situation, and when the generating system is operated in a parasitic mode, conversion efficiency is not an important consideration.

Rowe, M.D.; Min, G.; Williams, S.G.K.; Aoune, A. [Cardiff School of Engineering (United Kingdom). Div. of Electronic Engineering; Matsuura, Kenji [Osaka Univ., Suita, Osaka (Japan). Dept. of Electrical Engineering; Kuznetsov, V.L. [Ioffe Physical-Technical Inst., St. Petersburg (Russian Federation); Fu, L.W. [Tsinghua Univ., Beijing (China). Microelectronics Inst.

1997-12-31T23:59:59.000Z

453

PC-based control system complements NGL heat-recovery project  

SciTech Connect

Valero Hydrocarbons has employed a PC-based control system to realize the energy-savings potential of a heat-recovery project at its Corpus Christi, Tex., NGL fractionator (CCF). Valero Hydrocarbons' CCF was originally placed on-line in 1966. The operation of CCF as an isobutane-butane-natural gasoline fractionation complex started in 1982 after the plant's recovery section was replaced by the cryogenic unit at the nearby Shoup plant. The plant is still a significant Gulf Coast NGL processor, having a rated throughput of 10,000 b/d of the isobutane and heavier feedstock. The plant has operated successfully, however, at rates up to 11,300 b/d.

Young, R.M.

1988-05-02T23:59:59.000Z

454

Heat transfer studies, quarterly report  

SciTech Connect

Drying in subresidually-saturated systems at elevated temperatures has been studied for two different operating conditions. One condition started with flowing nitrogen gas through the test section and simultaneously heating up the porous medium at the same time (denoted in what follows as the ``transient heating case``). The other condition started initially with heating up the porous medium with no flow, and then running the nitrogen gas flow through the test section after a steady-state temperature distribution had been reached (denoted in what follows as the ``steady heating case``). A 90{degrees}C isothermal boundary condition was set on the aluminum wall. An average of 9% discrepancy in the mass balance calculation compared to the digital balance measurement has been found in the transient heating case. An average of 4.3% discrepancy in the mass balance calculation compared to the digital balance measurement has been found after the nitrogen gas flowed through test section for the steady heating case. A large discrepancy has also been found before the nitrogen gas admitted to the test section. This is because some of subresidual water in the test section has been drained out from the bottom due to the gravity effect and the strong convection flow in the porous medium before the nitrogen gas is admitted. This discrepancy may be reduced by closing the end tube at bottom before the nitrogen gas is admitted to the test section. The drying characteristics of this system are reported. A theoretical study has also been initiated in an attempt to supplement the experimental results, and this system is described in the report. A one-dimensional transient system is assumed in which a two-component (condensable and noncondensable) gas mixture flows through a porous medium with evaporation. The numerical calculation will be performed in the future work to compare to the experimental results.

Boehm, R.; Chen, Y.T.; Sathappan, A.K.

1996-01-19T23:59:59.000Z

455

Performance Analysis of Air-Source Variable Speed Heat Pumps and Various Electric Water Heating Options  

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

Analysis of Air- Analysis of Air- Source Variable Speed Heat Pumps and Various Electric Water Heating Options Jeffrey Munk Oak Ridge National Laboratory 2 Managed by UT-Battelle for the U.S. Department of Energy Presentation_name Acknowledgements * Tennessee Valley Authority - David Dinse * U.S. Department of Energy * Roderick Jackson * Tony Gehl * Philip Boudreaux * ZEBRAlliance 3 Managed by UT-Battelle for the U.S. Department of Energy Presentation_name Overview * Electric Water Heating Options - Conventional Electric Water Heaters - Heat Pump Water Heaters * Air-Source * Ground-Source - Solar Thermal Water Heater * Variable Speed Heat Pumps - Energy Use Analysis - Measured Performance - Operational Characteristics 4 Managed by UT-Battelle for the U.S. Department of Energy Presentation_name Water Heating Options

456

Recovery Act - Geothermal Technologies Program: Ground Source Heat Pumps Final Scientific/Technical Report  

SciTech Connect

A large centralized geothermal heat pump system was installed to provide ice making, space cooling, space heating, process water heating, and domestic hot water heating for an ice arena in Eagan Minnesota. This paper provides information related to the design and construction of the project. Additionally, operating conditions for 12 months after start-up are provided.

Nick Rosenberry, Harris Companies

2012-05-04T23:59:59.000Z

457

Model based methodology development for energy recovery in flash heat exchange systems  

E-Print Network (OSTI)

Model based methodology development for energy recovery in flash heat exchange systems Problem of energy efficiency in process operations. Where heat exchange is required between two streams and where with a condensing heat exchanger can be used when heat exchange is required between two streams and where at least

McCarthy, John E.

458

Modeling heat and mass transport phenomena at higher temperatures in solar distillation systems - The Chilton-Colburn analogy  

SciTech Connect

In the present investigation efforts have been devoted towards developing an analysis suitable for heat and mass transfer processes modeling in solar distillation systems, when they are operating at higher temperatures. For this purpose the use of Lewis relation is not new although its validity is based on the assumptions of identical boundary layer concentration and temperature distributions, as well as low mass flux conditions, which are not usually met in solar distillation systems operating at higher temperatures associated with considerable mass transfer rates. The present analysis, taking into consideration these conditions and the temperature dependence of all pertinent thermophysical properties of the saturated binary mixture of water vapor and dry air, leads to the development of an improved predictive accuracy model. This model, having undergone successful first order validation against earlier reported measurements from the literature, appears to offer more accurate predictions of the transport processes and mass flow rate yield of solar stills when operated at elevated temperatures. (author)

Tsilingiris, P.T. [Department of Energy Engineering, Heat Transfer Laboratory, Technological Education Institution of Athens, A. Spyridonos Street, GR 122 10 Egaleo, Athens (Greece)

2010-02-15T23:59:59.000Z

459

Energy Efficient Integration of Heat Pumps into Solar District Heating Systems with Seasonal Thermal Energy Storage  

Science Journals Connector (OSTI)

Abstract Solar district heating (SDH) with seasonal thermal energy storage (STES) is a technology to provide heat for space heating and domestic hot water preparation with a high fraction of renewable energy. In order to improve the efficiency of such systems heat pumps can be integrated. By preliminary studies it was discovered, that the integration of a heat pump does not always lead to improvements from an overall energy perspective, although the operation of the heat pump increases the efficiency of other components of the system e. g. the STES or the solar collectors. Thus the integration of heat pumps in SDH systems was investigated in detail. Usually, the heat pumps are integrated in such a way, that the STES is used as low temperature heat source. No other heat sources from the ambience are used and only that amount of energy consumed by the heat pump is additionally fed into the system. In the case of an electric driven heat pump, this is highly questionable concerning economic and CO2-emission aspects. Despite that fact the operation of the heat pump influences positively the performance of other components in the system e. g. the STES and makes them more efficient. If the primary energy consumption of the heat pump is lower than the energetic benefits of all other components, the integration makes sense from an energetic point of view. A detailed assessment has been carried out to evaluate the most promising system configurations for the integration of a heat pump. Based on this approach a system concept was developed in which the integration of the heat pump is energetically further improved compared to realised systems. By means of transient system simulations this concept was optimised with regard to the primary energy consumption. A parameter study of this new concept has been performed to identify the most sensitive parameters of the system. The main result and conclusion are that higher solar fractions and also higher primary energy savings can be achieved by SDH systems using heat pumps compared systems without heat pumps.

Roman Marx; Dan Bauer; Harald Drueck

2014-01-01T23:59:59.000Z

460

Wound tube heat exchanger  

DOE Patents (OSTI)

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

Ecker, Amir L. (Duncanville, TX)

1983-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "operating heat rate" 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

Heat Exchangers for Solar Water Heating Systems | Department of Energy  

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

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

462

Dynamics of heat transfer between nano systems  

E-Print Network (OSTI)

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

Svend-Age Biehs; Girish S. Agarwal

2012-10-18T23:59:59.000Z

463

Cryogenic heat exchanger with turbulent flows  

Science Journals Connector (OSTI)

An evaporator-type cryogenic heat exchanger is designed and built for introducing fluidsolid heat exchange phenomena to undergraduates in a practical and efficient way. The heat exchanger functions at liquid nitrogen temperature and enables cooling of N2and He gases from room temperatures. We present first the experimental results of various parameters which characterize the heat exchanger (efficiency, number of transfer units, heat exchange coefficient, etc) as a function of the mass flow rate of the gas to be cooled. An analysis of the NuRe diagram is also presented. All experiments were conducted with N2gas. The scope of this tool is readily extended to research purposes.

Jay Amrit; Christelle Douay; Francis Dubois; Grard Defresne

2012-01-01T23:59:59.000Z

464

Control system for fluid heated steam generator  

DOE Patents (OSTI)

A control system for controlling the location of the nucleate-boiling region in a fluid heated steam generator comprises means for measuring the temperature gradient (change in temperature per unit length) of the heating fluid along the steam generator; means for determining a control variable in accordance with a predetermined function of temperature gradients and for generating a control signal in response thereto; and means for adjusting the feedwater flow rate in accordance with the control signal.

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

1984-05-29T23:59:59.000Z

465

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

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

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